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Sample records for dental erosion caused

  1. Managing dental erosion.

    Science.gov (United States)

    Curtis, Donald A; Jayanetti, Jay; Chu, Raymond; Staninec, Michal

    2012-01-01

    The clinical signs of dental erosion are initially subtle, yet often progress because the patient remains asymptomatic, unaware and uninformed. Erosion typically works synergistically with abrasion and attrition to cause loss of tooth structure, making diagnosis and management complex. The purpose of this article is to outline clinical examples of patients with dental erosion that highlight the strategy of early identification, patient education and conservative restorative management. Dental erosion is defined as the pathologic chronic loss of dental hard tissues as a result of the chemical influence of exogenous or endogenous acids without bacterial involvement. Like caries or periodontal disease, erosion has a multifactorial etiology and requires a thorough history and examination for diagnosis. It also requires patient understanding and compliance for improved outcomes. Erosion can affect the loss of tooth structure in isolation of other cofactors, but most often works in synergy with abrasion and attrition in the loss of tooth structure (Table 1). Although erosion is thought to be an underlying etiology of dentin sensitivity, erosion and loss of tooth structure often occurs with few symptoms. The purpose of this article is threefold: first, to outline existing barriers that may limit early management of dental erosion. Second, to review the clinical assessment required to establish a diagnosis of erosion. And third, to outline clinical examples that review options to restore lost tooth structure. The authors have included illustrations they hope will be used to improve patient understanding and motivation in the early management of dental erosion.

  2. Saliva and dental erosion.

    Science.gov (United States)

    Buzalaf, Marília Afonso Rabelo; Hannas, Angélicas Reis; Kato, Melissa Thiemi

    2012-01-01

    Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. This review discusses the role of salivary factors on the development of dental erosion. A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

  3. Saliva and dental erosion

    Directory of Open Access Journals (Sweden)

    Marília Afonso Rabelo Buzalaf

    2012-10-01

    Full Text Available Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. Objective: This review discusses the role of salivary factors on the development of dental erosion. Material and Methods: A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Results: Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Conclusions: Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

  4. Dental erosion caused by gastroesophageal reflux disease: a case report

    OpenAIRE

    Cengiz, Seda; Cengiz, M ?nan?; Sara?, Y ?inasi

    2009-01-01

    Introduction Chronic regurgitation of gastric acids in patients with gastroesophageal reflux disease may cause dental erosion, which can lead in combination with attrition or bruxism to extensive loss of coronal tooth tissue. Case presentation This clinical report describes treatment of severe tooth wear of a gastroesophageal reflux disease patient who is 54-year-old Turkish male patient. After his medical treatment, severe tooth wear, bruxism and decreased vertical dimensions were determined...

  5. Restorative Management of Intrinsic and Extrinsic Dental Erosion.

    Science.gov (United States)

    Al-Salehi, Samira Kathryn

    2014-12-01

    The restorative management of tooth surface loss is highlighted through the presentation of two advanced cases of dental erosion. On presentation, the causes of the dental erosion in both patients had been previously diagnosed and stopped. The first patient was a 67 year old with intrinsic erosion and an element of attrition where a multidisciplinary approach was used. The other, a 17 year old patient with extrinsic erosion managed via adhesive restorations. Adhesive techniques are a relatively simple, effective and conservative method for the treatment of dental erosion. The two treatment modalities (conventional versus contemporary) are compared and discussed.

  6. On dental caries and dental erosion in Swedish young adults.

    Science.gov (United States)

    Isaksson, Helén

    2013-01-01

    All children in Sweden are entitled to regular, free dental care up to 20 years of age. While dental caries generally continues to decline, still there is a pronounced skewness in caries prevalence. Furthermore, the reported increase in dental erosion in young adults is cause for concern. The aim was to study the prevalence of dental caries and dental erosion in a cohort of Swedish 20 year-olds, with special reference to the influence of previous caries experience and lifestyle as well as parental, socioeconomic and psychosocial factors. The study was prospective, longitudinal and cross-sectional in design and based on registration of caries lesions, dental erosion, body adiposity status, saliva sampling, interviews, and questionnaires at 20 years of age. Data were available for the same cohort at 1, 3, 6 and 15 years of age. 499 subjects (74 percent of the original cohort) were included. Five individuals were subsequently excluded, leaving a final sample of 494. 74 percent of the subjects had initial and/or manifest caries lesions and/or restorations. The mean number of DimFS was 5.8 and the mean number of DmFS on occlusal surfaces of molars was 1.1. There was a strong relationship between caries activity at 3 and 6 years of age and approximal caries prevalence in premolars and molars at 20 years of age. Overweight/obese individuals had significantly higher caries prevalence than normal weight individuals. Parental, socioeconomic and psychosocial factors during infancy were related to approximal caries at age 20. Dental erosion was found in 75 percent of the individuals: 18 percent of these had extensive erosion. There was a significant association between caries and dental erosion. A relationship was found between dental erosion and lifestyle factors and overweight/obesity. There is a strong relationship between caries prevalence at age 20 and caries experience in early childhood. Young adults show a high prevalence of dental erosion, but the severity is

  7. Protection From Dental Erosion: All Fluorides are Not Equal.

    Science.gov (United States)

    Faller, Robert V; Noble, Warden H

    2018-03-01

    All fluoride sources help strengthen teeth against bacterial acids that cause caries. However, excessive exposure to dietary acids, which can result in dental erosion, presents a more aggressive level of challenge compared to caries. Despite the fact that almost all toothpastes contain fluoride, both the incidence and prevalence of dental erosion appear to be on the rise. This article: (1) describes key differences between caries and dental erosion and the ability of different fluoride sources to help prevent erosion; (2) discusses the importance of the evaluation of patients for dental erosion at the earliest stages using the Basic Erosive Wear Examination scoring system to help assess and educate patients; and (3) provides evidence-based information for making specific recommendations to patients with dental erosion. The objective of this article is to assess the comparative ability of fluoride agents to protect against dental erosion. Though all fluorides are able to help strengthen teeth against cariogenic acids, not all available sources of fluoride provide the same level of erosion protection. Daily use of a stabilized stannous fluoride dentifrice has been shown to provide the most effective means of protecting teeth against the increasing risk of dental erosion and erosive tooth wear.

  8. Dietary assessment and counseling for dental erosion.

    Science.gov (United States)

    Marshall, Teresa A

    2018-02-01

    Dental erosion occurs after exposure to intrinsic or extrinsic acids. Exposure to intrinsic gastrointestinal acids is associated with anorexia nervosa, bulimia nervosa, rumination syndrome, or gastroesophageal reflux. Extrinsic dietary acids from foods or beverages also can cause erosion, particularly when exposure is prolonged by holding or swishing behaviors. Clinicians should screen patients exhibiting dental erosion for anorexia nervosa, bulimia nervosa, rumination syndrome, and gastroesophageal reflux disease. Clinicians should screen patients without a medical explanation for their erosion for exposure to acidic foods and beverages, particularly for habits that prolong exposure. Identification of intrinsic and extrinsic acid exposures and recommendations to minimize exposures are important to prevent erosion and maintain oral health. Copyright © 2018 American Dental Association. Published by Elsevier Inc. All rights reserved.

  9. Medication-related dental erosion: a review.

    Science.gov (United States)

    Thomas, Manuel S; Vivekananda Pai, A R; Yadav, Amit

    2015-10-01

    Dental erosion has become a major problem that affects the long-term health of the dentition. Among the various potential causes for erosive tooth wear, the different drugs prescribed for patients may be overlooked. Several therapeutic medications can directly or indirectly be associated with dental erosion. It is the responsibility of oral health providers to make both patients and colleagues aware of drugs that may contribute to this condition. Therefore, the purpose of this discussion is to provide an overview of the various therapeutic medications that can be related to tooth erosion. The authors also include precautionary measures-summarized as The 9 Rs-to avoid or at least reduce medication-induced erosion.

  10. Evaluation of dental erosion prevalence and contributing factors in patients referring to yazd dental school in 2012-2013

    Directory of Open Access Journals (Sweden)

    Farnaz Farahat

    2016-03-01

    Full Text Available Background and Aims: Dental erosion refers to the loss of tooth structure by being scratched chemically without bacterial involvement which needs to care about due to its prevalence and treatment problems. This study was designed with the aim of evaluation of the frequency of dental erosion and its causing factors in patients referring to yazd dental school in 2012-2013. Materials and Methods: In this cross-sectional study, 400 patients referring to yazd dental school were randomly selected. All of their teeth were evaluated in three surfaces (buccal, lingual and occlusal. The BEWE score was used for classification the extent of damages. Also, patients were given a questionnaire that included patient demographic information and questions to investigate the causes of dental erosion. Data were analyzed using SPSS version 17 and Mann-Whiney, Fisher exact, and Chi-square tests. Results: In this study, 138 men and 261 women were participated with the mean age of 33.26±10.83. 84 persons (21.1% had erosion. There was a direct and significant relationship between the dental erosion and patient's age (P >0.001. Also, there was a direct relationship between the dental erosion and reflux and consumption of lemon and pickle, beverages, soft beer and juice (P>0.001. Conclusion: Consumption of lemon and pickle, beverages, soft beer and juice increases the risk of erosion. Considering the prevalence of dental erosion in about 21% of patients, it is necessary to pay more attention to the knowledge of the causes of erosion and reduction strategies of it.

  11. A Dental Hygienist's and Therapist's Guide to the Management of Tooth Erosion.

    Science.gov (United States)

    Ariyanayagam, Yana

    2016-08-01

    Dental care professionals can support patients to prevent and manage tooth erosion. The role of the dentist is to restore the structure and function of teeth damaged by acid erosion, while the role of the dental hygienist therapist is to work alongside the dentist to help manage and reduce the risk of tooth erosion. This article will highlight how the dental hygienist or therapist can identify tooth erosion. It will describe the features of tooth erosion and outline the causes. This article will discuss preventative care options for patients who are at risk of tooth erosion, including specific oral hygiene instructions, fluoride advice and use of other dental products.

  12. Dental erosion caused by gastroesophageal reflux disease: a case report.

    Science.gov (United States)

    Cengiz, Seda; Cengiz, M Inanç; Saraç, Y Sinasi

    2009-07-22

    Chronic regurgitation of gastric acids in patients with gastroesophageal reflux disease may cause dental erosion, which can lead in combination with attrition or bruxism to extensive loss of coronal tooth tissue. This clinical report describes treatment of severe tooth wear of a gastroesophageal reflux disease patient who is 54-year-old Turkish male patient. After his medical treatment, severe tooth wear, bruxism and decreased vertical dimensions were determined. The vertical dimension was re-established and maxillary and mandibular anterior and posterior teeth were prepared for metal-ceramic restorations. Metal-ceramic fixed partial dentures were fabricated as full mouth restorations for both maxillary and mandibular arches because of splinting all teeth. And then maxillary stabilization splint was fabricated for his bruxism history. Significant loss of coronal tooth structure must taken into consideration. Gastroesophageal reflux disease by itself or in combination with attrition, abrasion or bruxism may be responsible for the loss. An extensive diagnostic evaluation is essential for the medical and dental effects of the problem.

  13. Prevalence of dental erosion in 12-year-old schoolchildren of Lucknow city

    Directory of Open Access Journals (Sweden)

    Pooja Sinha

    2016-01-01

    Full Text Available Introduction: Dental erosion is tooth surface loss caused by chemical processes without bacterial involvement, which can affect children because of various dietary and other lifestyle factors. Aims: The aim of this study was to assess the prevalence of dental erosion in 12-year-old schoolchildren in Lucknow city. Materials and Methods: A total of 212 schoolchildren were selected through multistage cluster random sampling method. A pretested self-administered pro forma was used to record demographic data, medical history, and dietary habits. The clinical examination was done to evaluate dental erosion of children using dental erosion index by O'Sullivan. Descriptive analytical tests were used including distribution of erosion, its extent and severity. The findings were compared across the study participants using Chi-square test. Results: The overall prevalence of dental erosion was 34.12% with no significant sex difference. Dental erosion was significantly related to the frequency of consumption of fruit juices (67.07% followed by carbonated drinks (64.47%. In most of the cases, more than half of their surfaces were diagnosed as affected by erosion (26.25% central incisors, 4.83% lateral incisors. Conclusions: Dental erosion among the study group was found to be 34.12%, providing evidence that dental erosion is becoming a significant problem in Lucknow schoolchildren.

  14. Distinguishing and diagnosing contemporary and conventional features of dental erosion.

    Science.gov (United States)

    Bassiouny, Mohamed A

    2014-01-01

    The vast number and variety of erosion lesions encountered today require reconsideration of the traditional definition. Dental erosion associated with modern dietary habits can exhibit unique features that symbolize a departure from the decades-old conventional image known as tooth surface loss. The extent and diversity of contemporary erosion lesions often cause conflicting diagnoses. Specific examples of these features are presented in this article. The etiologies, genesis, course of development, and characteristics of these erosion lesions are discussed. Contemporary and conventional erosion lesions are distinguished from similar defects, such as mechanically induced wear, carious lesions, and dental fluorosis, which affect the human dentition.

  15. Dental formulations for the prevention of dental erosion

    DEFF Research Database (Denmark)

    2010-01-01

    The invention relates to a therapeutic method for preventing and/or inhibiting dental erosion in a mammalian subject, and the provision of a dental care product for performing the method. The dental care product of the invention comprises a starch-degrading enzyme of E. C. 3.2.1.1, wherein said...... product comprises less than 1 wt.% ionic surfactant, and preferably is substantially free of endoprotease and/or lipase. The properties of the dental care product serve to prevent and/or inhibit dental erosion in a subject that typically results from repeated exposure of the patient's tooth surfaces...

  16. Self-induced vomiting and dental erosion--a clinical study.

    Science.gov (United States)

    Uhlen, Marte-Mari; Tveit, Anne Bjørg; Stenhagen, Kjersti Refsholt; Mulic, Aida

    2014-07-29

    In individuals suffering from eating disorders (ED) characterized by vomiting (e.g. bulimia nervosa), the gastric juice regularly reaches the oral cavity, causing a possible risk of dental erosion. This study aimed to assess the occurrence, distribution and severity of dental erosions in a group of Norwegian patients experiencing self-induced vomiting (SIV). The individuals included in the study were all undergoing treatment at clinics for eating disorders and were referred to a university dental clinic for examinations. One calibrated clinician registered erosions using the Visual Erosion Dental Examination (VEDE) system. Of 72 referred patients, 66 (63 females and three males, mean age 27.7 years) were or had been experiencing SIV (mean duration 10.6 years; range: 3 - 32 years), and were therefore included in the study. Dental erosions were found in 46 individuals (69.7%), 19 had enamel lesions only, while 27 had both enamel and dentine lesions. Ten or more teeth were affected in 26.1% of those with erosions, and 9% had ≥10 teeth with dentine lesions. Of the erosions, 41.6% were found on palatal/lingual surfaces, 36.6% on occlusal surfaces and 21.8% on buccal surfaces. Dentine lesions were most often found on lower first molars, while upper central incisors showed enamel lesions most frequently. The majority of the erosive lesions (48.6%) were found in those with the longest illness period, and 71.7% of the lesions extending into dentine were also found in this group. However, despite suffering from SIV for up to 32 years, 30.3% of the individuals showed no lesions. Dental erosion commonly affects individuals with ED experiencing SIV, and is more often found on the palatal/lingual surfaces than on the buccal in these individuals, confirming a common clinical assumption.

  17. A clinical index for evaluating and monitoring dental erosion

    DEFF Research Database (Denmark)

    Larsen, I B; Westergaard, J; Stoltze, K

    2000-01-01

    This study describes a new fine-scaled system for classifying initial and advanced dental erosions. The system includes the use of study casts of the teeth in an epoxy resin with an accurate surface reproduction. The severity of erosion on each tooth surface is scored according to six grades...... of severity. In addition, the presence of a Class V restoration and dental erosion on the same surface increases the erosion score, as it is assumed that the need for restorative treatment can be caused by the erosion. A high inter-examiner agreement was found when the present scoring system was used by two...... of the oral cavity and are furthermore suitable for data analysis. The system is thereby well-suited for determining etiologic factors and monitoring the progression of erosion over time....

  18. Dental erosion: prevalence, incidence, and distribution

    NARCIS (Netherlands)

    Jager, D.H.J.; Amaechi, B.T.

    2015-01-01

    Dental erosion is one of the most common dental diseases and it is a growing problem. Numerous epidemiological studies have investigated the prevalence of dental erosion. For these studies different cross sections of the population are investigated. Large differences were found between countries,

  19. Restorative Rehabilitation of a Patient with Dental Erosion

    OpenAIRE

    AlShahrani, Mohammed Thamer; Haralur, Satheesh B.; Alqarni, Mohammed

    2017-01-01

    Dental erosion is the chemical dissolution of the tooth structure. Factors like eating disorders and gastrointestinal diseases are recognized as intrinsic factors for dental erosion. Advanced stages of dental erosion extensively damage the tooth morphology, consequently affecting both esthetics and functions. Reports indicate the growing prevalence of erosion, and hence knowledge of restorative rehabilitation of tooth erosion is an integral part of the contemporary dental practice. This clini...

  20. Factors affecting the dental erosion severity of patients with eating disorders.

    Science.gov (United States)

    Otsu, Mitsuhiro; Hamura, Akira; Ishikawa, Yuiko; Karibe, Hiroyuki; Ichijyo, Tomoyasu; Yoshinaga, Yoko

    2014-01-01

    Intraoral disease is a common occurrence in patients with eating disorders, particularly dental erosion, which frequently becomes severe and may hinder daily life. The severity varies from patient to patient. Understanding the underlying mechanisms may help prevent dental erosion in these patients. Accordingly, we investigated the relationship between the severity of erosion and the behavior of patients with eating disorders, with a focus on daily diet and vomiting behavior. A total 71 female eating disorder outpatients from the Clinical Center of Psychosomatic Dentistry of Nippon Dental University Hospital and the Psychosomatic Internal Medicine Department of Kudanzaka Hospital or who were hospitalized at Hasegawa Hospital were enrolled. Dental erosion severity and location were determined by oral examination. Patients who induced vomiting were queried on their behavior during vomiting and on routine diet habits. Patients with dental erosion were further divided into mild and severe groups based on the lesion severity and the groups compared. Dental erosion was observed in 43 of 50 subjects who induced vomiting. Dental erosion was most frequent on the palatal side of the anterior maxillary teeth, occurring in 81.3% of the subjects. There were significant differences observed between the mild and severe groups according to post-vomiting oral hygiene. Significantly more subjects in the mild group consumed large amounts of water before vomiting, and significantly more subjects in the severe group routinely consumed carbonated beverages or sweetened food. While self-induced vomiting is the main cause of dental erosion in eating disorder patients, the erosion severity may be affected by behavior when inducing vomiting or by routine consumption of certain foods and beverages. Addressing these factors may help prevent severe dental erosion in patients who chronically induce vomiting.

  1. Dental Erosion and Medical Conditions: An Overview of Aetiology, Diagnosis and Management.

    Science.gov (United States)

    Paryag, A; Rafeek, R

    2014-09-01

    Tooth wear or tooth surface loss is a normal physiological process and occurs throughout life but is considered pathological when the degree of destruction is excessive or the rate of loss is rapid, causing functional, aesthetic or sensitivity problems. The importance of tooth wear as a dental problem has been increasingly recognized. The findings of a study in Trinidad indicate that the prevalence of tooth wear in a Trinidadian population is comparable to the United Kingdom (UK) and, indeed, that the level of moderate and severe wear is in fact nearly twice as high. The aetiology of tooth wear is attributed to four causes: erosion, attrition, abrasion and abfraction. Erosion is generally considered to be the most prevalent cause of tooth wear in the UK and Europe. Acids that cause dental erosion originate mainly from the diet or the stomach and to a lesser extent, the environment. Underlying medical problems can contribute to the progress of tooth wear due to erosion and the patient may not be aware of these conditions. Moderate to severe tooth wear poses a significant clinical challenge to dental practitioners and may result in treatment that is more complex and costly to the patient both in terms of finances and time spent in the dental chair. This paper provides an overview of aetiology and diagnosis of tooth wear, in particular tooth wear due to erosion, so that medical and dental practitioners may recognize tooth wear early, institute preventive measures and manage patients appropriately.

  2. Dental erosion among 12 year-old Libyan schoolchildren.

    Science.gov (United States)

    Huew, R; Waterhouse, P J; Moynihan, P J; Maguire, A

    2012-12-01

    As there are limited data on dental erosion in Libya, the aim of this study was to assess the prevalence and severity of dental erosion in a sample of 12 year-old children in Benghazi, Libya. Cross-sectional observational study. Elementary schools in Benghazi, Libya. A random sample of 791 12 year-old children (397 boys and 394 girls) attending 36 schools. Clinical dental examination for erosion using UK National Diet and Nutrition Survey (2000) criteria and self-completion questionnaire. The area and depth of dental erosion affecting the labial and palatal surfaces of the upper permanent incisors and occlusal surfaces of the first permanent molars. Dental erosion was observed in 40.8% of subjects; into enamel affecting 32.5%, into dentine affecting 8.0% and into pulp affecting 0.3% of subjects. Based on area affected, 323 subjects (40.8%) exhibited dental erosion (code > 0), with 32.6% of these subjects having erosion affecting more than two thirds of one or more surfaces examined. Mean total scores for dental erosion for all surfaces per mouth by area and by depth were both 2.69 (sd 3.81). Of the 9492 tooth surfaces examined, 2128 surfaces (22.4%) had dental erosion. Girls had more experience of erosion than boys at all levels of severity (p = 0.001). In a cohort of 12 year-old Libyan schoolchildren, more than one third of children examined showed dental erosion, requiring clinical preventive counselling. Significantly more erosion occurred in girls than boys.

  3. Restorative Rehabilitation of a Patient with Dental Erosion.

    Science.gov (United States)

    AlShahrani, Mohammed Thamer; Haralur, Satheesh B; Alqarni, Mohammed

    2017-01-01

    Dental erosion is the chemical dissolution of the tooth structure. Factors like eating disorders and gastrointestinal diseases are recognized as intrinsic factors for dental erosion. Advanced stages of dental erosion extensively damage the tooth morphology, consequently affecting both esthetics and functions. Reports indicate the growing prevalence of erosion, and hence knowledge of restorative rehabilitation of tooth erosion is an integral part of the contemporary dental practice. This clinical report describes an adult patient with gastroesophageal reflux induced dental erosion involving the palatal surface of the maxillary anterior teeth. The extensive involvement of the palatal surfaces compromised the esthetics, incisal guidance, and functional occlusal efficiency. Indirect all-ceramic restorations were utilized to restore the esthetics and occlusal reconstruction. In conclusion, patients affected by severe dental erosion require prosthetic rehabilitation besides the management of the associated medical condition.

  4. Restorative Rehabilitation of a Patient with Dental Erosion

    Directory of Open Access Journals (Sweden)

    Mohammed Thamer AlShahrani

    2017-01-01

    Full Text Available Dental erosion is the chemical dissolution of the tooth structure. Factors like eating disorders and gastrointestinal diseases are recognized as intrinsic factors for dental erosion. Advanced stages of dental erosion extensively damage the tooth morphology, consequently affecting both esthetics and functions. Reports indicate the growing prevalence of erosion, and hence knowledge of restorative rehabilitation of tooth erosion is an integral part of the contemporary dental practice. This clinical report describes an adult patient with gastroesophageal reflux induced dental erosion involving the palatal surface of the maxillary anterior teeth. The extensive involvement of the palatal surfaces compromised the esthetics, incisal guidance, and functional occlusal efficiency. Indirect all-ceramic restorations were utilized to restore the esthetics and occlusal reconstruction. In conclusion, patients affected by severe dental erosion require prosthetic rehabilitation besides the management of the associated medical condition.

  5. Dental erosion: understanding this pervasive condition.

    Science.gov (United States)

    Almeida e Silva, Júnio S; Baratieri, Luiz Narciso; Araujo, Edson; Widmer, Nicolas

    2011-08-01

    Dental erosion is a contemporary disease, mostly because of the change of the eating patterns that currently exist in society. It is a "silent" and multifactorial disease, and is highly influenced by habits and lifestyles. The prevalence of dental erosion has considerably increased, with this condition currently standing as a great challenge for the clinician, regarding the diagnosis, identification of the etiological factors, prevention, and execution of an adequate treatment. This article presents a dental erosion review and a case report of a restorative treatment of dental erosion lesions using a combination of bonded ceramic overlays to reestablish vertical dimension and composite resin to restore the worn palatal and incisal surfaces of the anterior upper teeth. Adequate function and esthetics can be achieved with this approach. © 2011 Wiley Periodicals, Inc.

  6. Assessment and management of dental erosion.

    Science.gov (United States)

    Wang, Xiaojie; Lussi, Adrian

    2010-07-01

    Studies have shown a growing trend toward increasing prevalence of dental erosion, associated with the declining prevalence of caries disease in industrialized countries. Erosion is an irreversible chemical process that results in tooth substance loss and leaves teeth susceptible to damage as a result of wear over the course of an individual's lifetime. Therefore, early diagnosis and adequate prevention are essential to minimize the risk of tooth erosion. Clinical appearance is the most important sign to be used to diagnose erosion. The Basic Erosive Wear Examination (BEWE) is a simple method to fulfill this task. The determination of a variety of risk and protective factors (patient-dependent and nutrition-dependent factors) as well as their interplay are necessary to initiate preventive measures tailored to the individual. When tooth loss caused by erosive wear reaches a certain level, oral rehabilitation becomes necessary. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Dental Erosion and Caries Status of Chinese University Students.

    Science.gov (United States)

    Chu, Chun Hung; Ng, Alice; Chau, Alex Man Him; Lo, Edward Chin Man

    2015-01-01

    To describe the prevalence and severity of dental erosion and caries experience of Chinese university students in Hong Kong. First-year Chinese students were invited to attend a dental clinic at a university campus in Hong Kong during their freshman orientation. A questionnaire was used to investigate the potential factors affecting their dental status, including sociodemographic factors, toothbrushing habits, dietary habits (consumption of sugary drinks), time elapsed since last dental check-up and self-perceived dental erosion status. Three calibrated dentists performed the clinical examinations. Dental erosion was evaluated using the modified Basic Erosive Wear Examination (BEWE) and dental caries experience was measured using the DMFT index. In total, 600 participants aged 18-21 were examined and 44% showed some signs of dental erosion (maximum BEWE > 0). Severe dental erosion (BEWE = 3) was found in 1% of the adults. Many (69%) had caries experience (DMFT > 0); their mean DMFT score was 2.5 ± 2.7 (± SD). The total BEWE scores were found to be associated with age and self-perception of tooth misalignment. No correlation was found between BEWE score and dietary habits, oral hygiene practices or self-perceived dental erosion status. Females, those whose last dental check-up was more than a year ago and those who perceived having dental decay or tooth wear had higher caries experience. Nearly half of the Chinese Hong Kong university students had signs of dental erosion, but very few showed signs of severe erosion. Caries experience was widespread but not high.

  8. Gastroesophageal reflux is not associated with dental erosion in children.

    Science.gov (United States)

    Wild, Yvette K; Heyman, Melvin B; Vittinghoff, Eric; Dalal, Deepal H; Wojcicki, Janet M; Clark, Ann L; Rechmann, Beate; Rechmann, Peter

    2011-11-01

    Dental erosion is a complication of gastroesophageal reflux (GER) in adults; in children, it is not clear if GER has a role in dental pathologic conditions. Dietary intake, oral hygiene, high bacterial load, and decreased salivary flow might contribute independently to GER development or dental erosion, but their potential involvement in dental erosion from GER is not understood. We investigated the prevalence of dental erosion among children with and without GER symptoms, and whether salivary flow rate or bacterial load contribute to location-specific dental erosion. We performed a cross-sectional study of 59 children (ages, 9-17 y) with symptoms of GER and 20 asymptomatic children (controls); all completed a questionnaire on dietary exposure. Permanent teeth were examined for erosion into dentin, erosion locations, and affected surfaces. The dentist was not aware of GER status, and the gastroenterologist was not aware of dental status. Stimulated salivary flow was measured and salivary bacterial load was calculated for total bacteria, Streptococcus mutans, and Lactobacilli. Controlling for age, dietary intake, and oral hygiene, there was no association between GER symptoms and dental erosion by tooth location or affected surface. Salivary flow did not correlate with GER symptoms or erosion. Erosion location and surface were independent of total bacteria and levels of Streptococcus mutans and Lactobacilli. Location-specific dental erosion is not associated with GER, salivary flow, or bacterial load. Prospective studies are required to determine the pathogenesis of GER-associated dental erosion and the relationship between dental caries to GER and dental erosion. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. Sports drink consumption and dental erosion among amateur runners.

    Science.gov (United States)

    Antunes, Leonardo S; Veiga, Lais; Nery, Victor S; Nery, Caio C; Antunes, Lívia A

    2017-01-01

    This cross-sectional study assessed the prevalence and potential risk factors for dental erosion in amateur athletes at running events. After a sample calculation, 108 runners from the state of Rio de Janeiro, Brazil, were selected and examined for dental wear by a single trained and calibrated evaluator (kappa = 1.00). To identify risk factors, the runners were interviewed by using a standardized, semi-structured questionnaire. The average (SD) age of the runners was 34.2 (11.45), and the prevalence of dental erosion was 19.4%. Gastroesophageal reflux, running frequency per week, and time expended during competition were associated with dental erosion (P dental erosion was not significant (P > 0.05). In conclusion, dental erosion was not associated with use of isotonic drinks. However, frequency of exercise per week and gastroesophageal reflux were risk factors for dental erosion.

  10. Dental Erosion in Children with Gastroesophageal Reflux Disease.

    Science.gov (United States)

    De Oliveira, Patricia Alves Drummond; Paiva, Saul Martins; De Abreu, Mauro Henrique Nogueira Guimarães; Auad, Sheyla Márcia

    2016-01-01

    The purpose of this study was to investigate the impact of gastroesophageal reflux disease (GERD) on dental erosion (DE) in children and analyze the association between dental erosion and diet, oral hygiene, and sociodemographic characteristics. This case-control study encompassed 43 two- to 14-year-olds diagnosed positive for GERD by the 24-hour pH monitoring, paired by age group with 136 healthy controls, in Belo Horizonte, Minas Gerais, Brazil. DE was assessed by one calibrated examiner using the O'Sullivan index. A questionnaire was self-administered by parents collecting information regarding sociodemographics, oral hygiene, and dietary habits. Dental erosion experience was compared between the groups, and a stratified analysis was performed (PDental erosion was diagnosed in 10.6 percent (N equals 19) of all the children; 25.6 percent (N equals 11) of GERD children and 5.9 percent (N equals eight) of children without GERD, P=0.001). Dental erosion was not associated with dietary consumption or sociodemographic characteristics in both groups (P≥0.05). Children who used adult toothpaste had a 5.79 higher chance of having dental erosion in the group with GERD. Children diagnosed with gastroesophageal reflux disease were at an increased risk of having dental erosion when compared to healthy subjects; among the GERD children, dental erosion was associated with the use of adult toothpaste.

  11. Dental caries and its association with diet and dental erosion in Libyan schoolchildren.

    Science.gov (United States)

    Huew, Rasmia; Waterhouse, Paula; Moynihan, Paula; Kometa, Simon; Maguire, Anne

    2012-01-01

    BACKGROUND. The change towards a more Westernised diet in Libya may increase the risk of caries and erosion in children. AIMS. To investigate any association between dental caries, dental erosion, and potential dietary risk factors in Libyan schoolchildren. METHODS. A random sample of 791 schoolchildren aged 12 years underwent dental examination for caries and erosion and completed a questionnaire to provide dietary data. Dental caries was assessed using the WHO (Oral Health Surveys: Basic Methods, 1997) criteria. Erosion was assessed using UK National Diet and Nutrition Survey (NDNS, Young People Aged 4-18 years. Volume 2: Report of the Oral Health Survey, 2000) criteria. Associations between caries and dietary variables were investigated through bivariate and multivariate analyses. RESULTS. Of the 791 12-year olds, 57.8% (457) had caries experience and 40.8% (323) had experience of erosion. One hundred and ninety-two subjects (42%) of the subjects with caries experience also had erosion, whilst 131 subjects (39.2%) of the 334 without caries had clinical signs of erosion (P = 0.464; OR, 1.123; 95% CI, 0.842, 1.497). There was no statistically significantly relationship between dental caries and dental erosion. Frequency of consumption of fruit-based sugared drinks was statistically significantly positively associated with experience of caries (P = 0.002). CONCLUSIONS. Dental caries experience was associated with frequency of consumption of sugared dietary items but not with dental erosion. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

  12. Is dental erosion really a problem?

    Science.gov (United States)

    Schlueter, N; Jaeggi, T; Lussi, A

    2012-09-01

    Dental erosion is the non-carious dental substance loss induced by direct impact of exogenous or endogenous acids. It results in a loss of dental hard tissue, which can be serious in some groups, such as those with eating disorders, in patients with gastroesophageal reflux disease, and also in persons consuming high amounts of acidic drinks and foodstuffs. For these persons, erosion can impair their well-being, due to changes in appearance and/or loss of function of the teeth, e.g., the occurrence of hypersensitivity of teeth if the dentin is exposed. If erosion reaches an advanced stage, time- and money-consuming therapies may be necessary. The therapy, in turn, poses a challenge for the dentist, particularly if the defects are diagnosed at an advanced stage. While initial and moderate defects can mostly be treated non- or minimally invasively, severe defects often require complex therapeutic strategies, which often entail extensive loss of dental hard tissue due to preparatory measures. A major goal should therefore be to diagnose dental erosion at an early stage, to avoid functional and esthetic impairments as well as pain sensations and to ensure longevity of the dentition.

  13. Direct restorative treatment of dental erosion caused by gastroesophageal reflux disease associated with bruxism: a case report

    OpenAIRE

    Vidal, Cristina de Mattos Pimenta [UNESP; Catelan, Anderson [UNESP; Briso, André Luiz Fraga [UNESP; Santos, Paulo Henrique dos [UNESP

    2011-01-01

    Gastroesophageal reflux disease (GERD) is a gastrointestinal disorder in which stomach acids are chronically regurgitated into the esophagus and oral cavity. Continual exposure of the teeth to these acids can cause severe tooth wear. Dentists are often the first healthcare professionals to diagnose dental erosion in patients with GERD. This article presents a case report of a 27-year-old male smoker with tooth wear and dentin sensitivity caused by GERD associated with bruxism. After diagnosis...

  14. DENTAL EROSION IN PRIMARY DENTITION- A REVIEW

    Directory of Open Access Journals (Sweden)

    Rafi Shaik

    2017-06-01

    Full Text Available BACKGROUND The pattern of oral diseases has been influenced by ever changing human lifestyle. Tooth wear especially dental erosion has drawn increasing attention as risk factor for tooth damage or loss in recent years. It is a common condition in primary dentition compared to permanent dentition due to thinner and less mineralised enamel. However, it is more worrying, when this condition is being found in an alarming proportion among children. The presence of dental erosion in children is likely to be associated with a number of general health and dietary factors, but it is also aggravated by the relatively more rapid progression of erosion in the deciduous teeth. An understanding of the aetiologies and risk factors for erosion is important for early recognition of dental erosion to prevent serious irreversible damage to the dentition. This paper discusses the erosion in children with regard to its epidemiology, prevalence, clinical features, measurement and prevention.

  15. Reflux disease as an etiological factor of dental erosion

    Directory of Open Access Journals (Sweden)

    Stojšin Ivana

    2010-01-01

    Full Text Available Introduction Gastroesophageal reflux is a frequent disease which has a significant influence on the development of dental erosions. Objective The aim of this research was to determine the frequency of dental erosions among the patients with gastroesophageal reflux, as well as to verify the most common symptoms of gastroesophageal disease. Methods The research comprised of two groups, each consisting of 30 patients aged 18-80 years. The experimental group comprised of patients diagnosed with gastroesophageal reflux disease (GERD, while the control group was composed of patients who were not diagnosed with GERD. Based on the illness history data, all patients of the experimental group were registered to have gastroesophageal and extraesophageal symptoms. Dental erosions were diagnosed during a stomatological inspection by using index system according to Eccles and Jenkins. Data processing was accomplished by the Statgraphics Centurion software package. Results Dental erosions were found in 76.7% of experimental group patients, and in 53.3% of control group patients. Fortynine percent of teeth of the experimental group patients and 31.1% of the control group patients showed erosive changes. On average, the number of teeth with erosions in the experimental group was 15.7 per person and in the control group 10 per person. The teeth of the front region of the upper jaw, as well as the lower first molars had the highest average value of dental erosion index. In the experimental group 12.8% of teeth and 24% of teeth in the control group were diagnosed to have dental erosion index value 1. Furthermore, 23.4% of teeth in the experimental group and 7.1% of teeth in the control group were registered to have dental erosion index value 2. Finally, the dental erosion index value 3 was found in 13.0% of teeth in the experimental group only. The highest average value of regional erosion index in the experimental group was found in the region 13-23 equalling 1

  16. Direct restorative treatment of dental erosion caused by gastroesophageal reflux disease associated with bruxism: a case report.

    Science.gov (United States)

    Vidal, Cristina de Mattos Pimenta; Catelan, Anderson; Briso, André Luiz Fraga; dos Santos, Paulo Henrique

    2011-09-01

    Gastroesophageal reflux disease (GERD) is a gastrointestinal disorder in which stomach acids are chronically regurgitated into the esophagus and oral cavity. Continual exposure of the teeth to these acids can cause severe tooth wear. Dentists are often the first healthcare professionals to diagnose dental erosion in patients with GERD. This article presents a case report of a 27-year-old male smoker with tooth wear and dentin sensitivity caused by GERD associated with bruxism. After diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow-up with counseling on dietary and smoking habits, as well as management of the gastric disorders with medication. GERD management and the dental treatment performed for the eroded dentition are described, including diagnosis, treatment planning, and restorative therapy.

  17. Erosion and abrasion on dental structures undergoing at-home bleaching

    Directory of Open Access Journals (Sweden)

    Tarquinio SBC

    2011-07-01

    Full Text Available Flávio Fernando Demarco1, Sônia Saeger Meireles2, Hugo Ramalho Sarmento1, Raquel Venâncio Fernandes Dantas1, Tatiana Botero3, Sandra Beatriz Chaves Tarquinio11Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Brazil; 2Department of Operative Dentistry, Federal University of Paraíba, Brazil; 3Cariology, Restorative Science, and Endodontics Department, School of Dentistry, University of Michigan, MI, USAAbstract: This review investigates erosion and abrasion in dental structures undergoing at-home bleaching. Dental erosion is a multifactorial condition that may be idiopathic or caused by a known acid source. Some bleaching agents have a pH lower than the critical level, which can cause changes in the enamel mineral content. Investigations have shown that at-home tooth bleaching with low concentrations of hydrogen or carbamide peroxide have no significant damaging effects on enamel and dentin surface properties. Most studies where erosion was observed were in vitro. Even though the treatment may cause side effects like sensitivity and gingival irritation, these usually disappear at the end of treatment. Considering the literature reviewed, we conclude that tooth bleaching agents based on hydrogen or carbamide peroxide have no clinically significant influence on enamel/dentin mineral loss caused by erosion or abrasion. Furthermore, the treatment is tolerable and safe, and any adverse effects can be easily reversed and controlled.Keywords: peroxide, tooth bleaching, enamel, dentin, erosion, abrasion

  18. Prevalence of dental erosion among people with gastroesophageal reflux disease in China.

    Science.gov (United States)

    Li, Wenhao; Liu, Jingming; Chen, Su; Wang, Yao; Zhang, Zhenting

    2017-01-01

    Gastroesophageal reflux disease (GERD) is typically diagnosed based on symptoms of regurgitation and heartburn, although it may also manifest as asthma-like symptoms, laryngitis, or dental erosion. The purpose of this prospective, cross-sectional study was to assess the prevalence of dental erosion in people with GERD and to evaluate the association between GERD and dental erosion. The presence, severity, and pattern of dental erosion was assessed in 51 participants with GERD and 50 participants without GERD using the Smith and Knight tooth wear index. Medical, dietary, and dental histories were collected by questionnaire. Factors potentially related to dental erosion, including GERD, were evaluated by logistic regression. Dental erosion was observed in 31 (60.8%) participants with GERD and 14 (28%) participants without GERD. Bivariate analysis revealed that participants with GERD were more likely to experience dental erosion (crude odds ratio [cOR]: 2.74; 95% CI: 1.19, 6.32) than participants without GERD. Multivariate analysis also revealed that participants with GERD had a higher risk of dental erosion (adjusted odds ratio [aOR]: 3.97; 95% CI: 1.45, 10.89). Consumption of grains and legumes, the most frequently consumed foods in China, did not correlate with dental erosion. However, carbonated beverage consumption was significantly associated with GERD and dental erosion (aOR: 3.34; 95% CI: 1.01, 11.04; P=.04). GERD was positively correlated with dental erosion. Carbonated beverage consumption can increase the risk of both GERD and dental erosion. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  19. Techniques to Evaluate Dental Erosion: A Systematic Review of Literature.

    Science.gov (United States)

    Joshi, Mahasweta; Joshi, Nikhil; Kathariya, Rahul; Angadi, Prabhakar; Raikar, Sonal

    2016-10-01

    This article reviews different techniques for evaluating dental erosion, weighs the advantages and disadvantages of these techniques, and presents the latest trends in the study of dental erosion. In May 2014, an initial search was carried out in the PubMed/MEDLINE database of indexed journals from 1975 to 2013 using the following keywords: dental erosion; dental erosion In-vitro; and dental erosion in-vivo. Bibliographic citations from the papers found were then used to find other useful sources. The authors categorize the techniques into three classes: in-vitro, in-vivo and in-vitro/in-vivo. The article discusses the instrumentation required to use each of these techniques, as well as their rationale, merits and applications. The emergence of in-vitro/in-vivo techniques offers the potential to accurately quantify tooth wear in clinical situations. Cross-sectional as well as longitudinal studies show that these techniques will improve diagnosis, treatment planning and management of dental erosion.

  20. Dental erosion and its association with diet in Libyan schoolchildren.

    Science.gov (United States)

    Huew, R; Waterhouse, P J; Moynihan, P J; Kometa, S; Maguire, A

    2011-10-01

    To investigate any association between dental erosion and its potential dietary risk factors in a group of schoolchildren in Benghazi, Libya. A cross-sectional observational study. A random sample of 12-year-old schoolchildren in 36 randomly selected schools completed a questionnaire to provide dietary data and underwent dental examination. Dental erosion was assessed using UK National Diet and Nutrition Survey (2000) criteria. Associations between erosion and dietary variables under study were investigated through processes of bivariate and multivariate analyses. Of 791 schoolchildren dentally examined, 40.8% had dental erosion; erosion into enamel affecting 32.5%, into dentine affecting 8% and into pulp affecting 0.3% of subjects. Bivariate analysis showed frequency of fruit-based sugary drink intake was statistically significantly and positively associated with erosion (p=0.006, Odds Ratio; 1.498, 95% CI; 1.124, 1.996) as was the length of time taken to consume acidic drinks (p≠0.005, Odds Ratio; 1.593, 95%CI; 1.161, 2.186). Additionally, multivariate analysis showed frequency of consumption of fruit other than bananas, sugared tea with milk and flavoured milk to also be positively associated with erosion (p=dental erosion.

  1. Prevalence and risk factors of dental erosion in American children.

    Science.gov (United States)

    Habib, Mariam; Hottel, Timothy L; Hong, Liang

    2013-01-01

    The purpose of this study was to assess the prevalence and characteristics of dental erosion in children aged 2-4 years old and 12 years old. 243 subjects were recruited from daycare centers, preschools, and grade schools; they received dental examinations assessing their condition of dental erosion, including both depth and area of tooth surface loss on four maxillary incisors. Questionnaires were given to the subjects to obtain socio-demographic, oral health behaviors at home, and access to dental care. Dental erosion was analyzed and risk factors were assessed using Chi-Square and logistic regression analysis. The subjects were 60% Caucasians, 31% Black, 7% Hispanic and others were 2%. 34% of children could not get the dental care they needed within the past 12 months and 61% of all children brushed their teeth twice or more daily. Overall, 12% of study children had dental erosion with 13% for 2-4 years old and 10% for 12 years old, with the majority of erosive lesions within enamel. Family income (OR 3.98, p = 0.021) and acidic fruit juice consumption (OR 2.38, p = 0.038) were significant risk factors for dental erosion, even after controlling for other factors, such as source of drinking water and oral hygiene using logistic regression analysis. Dental erosion is a relatively common problem among the children in this study and it is seen as a multi-factorial process.

  2. Dental approach to erosive tooth wear in gastroesophageal reflux ...

    African Journals Online (AJOL)

    2014-06-02

    Jun 2, 2014 ... Objective: To summarize the diagnostic protocol and treatment of dental erosion due to GERD. Methods: A Medline ..... reflux in children with cerebral palsy and its relationship to erosion of ... phate (ACP) on root surface hypersensitivity. Operative ... Lussi A. Dental erosion clinical diagnosis and case.

  3. Prevalence of dental erosion in Greek minority school children in Istanbul.

    Science.gov (United States)

    Caglar, E; Sandalli, N; Panagiotou, N; Tonguc, K; Kuscu, O O

    2011-10-01

    To evaluate the prevalence and aetiology of dental erosion in Greek minority school children living in Istanbul (Turkey). The present study was initiated in four Greek minority elementary schools in Istanbul where a total of 83 children (46 girls, 37 boys) between ages 7-14 years old were examined. Children were categorised into 7-11 and 12-14 ages groups. Data were obtained by clinical examination, questionnaire and standard data records. All tooth surfaces were examined, dental erosion was recorded per tooth and classified according to the index of Lussi et al. [1996] In the 7-11 yrs old group, 47.4% (n:18) of the children exhibited dental erosion while in 12-14 yrs old group, 52.6% (n:20) of the children exhibited dental erosion. There were no statitistical differences between age, gender groups and findings of dental erosion (p>0.05). However prevalence of dental erosion in 12-14 yrs old was twice that of the 7-11 years old children. In general, an unusual drinking pattern of slow swallowing of beverages significantly affected the prevalence of dental erosion (p=0.03). Multiple regression analysis revealed no relationship between dental erosion and related erosive sources such as medical conditions, brushing habits, swimming, and the consumption of acidic fruit juices and beverages (p>0.05). However it should be noted that the sample size in the current study was small.

  4. Dental erosion in 12-year-old school children living in Jakarta

    Science.gov (United States)

    Septalita, A.; Bahar, A.; Agustanti, A.; Rahardjo, A.; Maharani, D. A.; Rosalien, R.

    2017-08-01

    This study assesses the dental erosion status of 12-year-old Indonesian children and studies the determinants of dental erosion of these children. The survey was performed in 2016 with ethics approval. A multistage cluster proportional to size random sampling method was adopted to select 12-year-old children in 24 primary schools in Jakarta. The parents were asked to complete a self-administered questionnaire concerning their children’s diet and oral health habits. The children were examined by a single calibrated examiner. Detection of dental erosion followed basic erosive wear examination (BEWE) criteria. A total of 487 children participated in the survey. Most children (88%) had at least some signs of erosion (BEWE > 0), with dentin being involved in 50% of the cases (BEWE = 2). Dental erosion was significantly related to gender, the frequencies of citric tea consumption, parent’s dental knowledge, father’s education, and dental caries (OR = 3.148). The 12-year-old Indonesian school children who lived in Jakarta had signs of erosion, although severe erosion was not found. Screening programs should be provided to identify risk groups so early preventive measures can be taken.

  5. Surface kinetic roughening caused by dental erosion: An atomic force microscopy study

    Science.gov (United States)

    Quartarone, Eliana; Mustarelli, Piercarlo; Poggio, Claudio; Lombardini, Marco

    2008-05-01

    Surface kinetic roughening takes place both in case of growth and erosion processes. Teeth surfaces are eroded by contact with acid drinks, such as those used to supplement mineral salts during sporting activities. Calcium-phosphate based (CPP-ACP) pastes are known to reduce the erosion process, and to favour the enamel remineralization. In this study we used atomic force microscopy (AFM) to investigate the surface roughening during dental erosion, and the mechanisms at the basis of the protection role exerted by a commercial CPP-ACP paste. We found a statistically significant difference (p<0.01) in the roughness of surfaces exposed and not exposed to the acid solutions. The treatment with the CPP-ACP paste determined a statistically significant reduction of the roughness values. By interpreting the AFM results in terms of fractal scaling concepts and continuum stochastic equations, we showed that the protection mechanism of the paste depends on the chemical properties of the acid solution.

  6. Composition of enamel pellicle from dental erosion patients.

    Science.gov (United States)

    Carpenter, G; Cotroneo, E; Moazzez, R; Rojas-Serrano, M; Donaldson, N; Austin, R; Zaidel, L; Bartlett, D; Proctor, G

    2014-01-01

    Oral health is dependent upon a thin mobile film of saliva on soft and hard tissues. Salivary proteins adhere to teeth to form the acquired enamel pellicle which is believed to protect teeth from acid erosion. This study investigated whether patients suffering diet-induced dental erosion had altered enamel pellicles. Thirty patients suffering erosion were compared to healthy age-matched controls. Subjects wore a maxillary splint holding hydroxyapatite and human enamel blocks for 1 h. The acquired enamel pellicle was removed from the blocks and compared to the natural incisor pellicle. Basic Erosive Wear Examination scores confirmed that dental erosion was present in erosion patients and absent from healthy age-matched controls. Erosion patients had half the amount of proteins (BCA assay) within the acquired pellicle forming on splint blocks compared to normal controls (p erosion patients (p erosion patients and healthy controls. In summary, the formation of new acquired pellicles on surfaces was reduced in erosion patients, which may explain their greater susceptibility to acid erosion of teeth. © 2014 S. Karger AG, Basel.

  7. Dental erosion due to lime consumption; review of literature and ...

    African Journals Online (AJOL)

    Background: Dental health is increasingly threatened by dental erosion introduced by today's lifestyle. Extrinsic factor is the most implicated. Few literatures mentioned lime-incited dental erosion. Case Description: A 49 year old woman was referred to our clinic with tooth wear and sensitivity. She was in good health but on ...

  8. Prevalence of Dental Erosion among the Young Regular Swimmers in Kaunas, Lithuania.

    Science.gov (United States)

    Zebrauskas, Andrius; Birskute, Ruta; Maciulskiene, Vita

    2014-04-01

    To determine prevalence of dental erosion among competitive swimmers in Kaunas, the second largest city in Lithuania. The study was designed as a cross-sectional survey, with a questionnaire and clinical examination protocols. The participants were 12 - 25 year-old swimmers regularly practicing in the swimming pools of Kaunas. Of the total of 132 participants there were 76 (12 - 17 year-old) and 56 (18 - 25 year-old) individuals; in Groups 1 and 2, respectively. Participants were examined for dental erosion, using a portable dental unit equipped with fibre-optic light, compressed air and suction, and standard dental instruments for oral inspection. Lussi index was applied for recording dental erosion. The completed questionnaires focused on the common erosion risk factors were returned by all participants. Dental erosion was found in 25% of the 12 - 17 year-olds, and in 50% of 18 - 25 years-olds. Mean value of the surfaces with erosion was 6.31 (SD 4.37). All eroded surfaces were evaluated as grade 1. Swimming training duration and the participants' age correlated positively (Kendall correlation, r = 0.65, P dental erosion and the analyzed risk factors (gastroesophageal reflux disease, frequent vomiting, dry mouth, regular intake of acidic medicines, carbonated drinks) was found in both study groups. Prevalence of dental erosion of very low degree was high among the regular swimmers in Kaunas, and was significantly related to swimmers' age.

  9. Dental erosion: Prevalence and severity among 16-year-old adolescents in Troms, Norway.

    Science.gov (United States)

    Mulic, A; Fredriksen, Ø; Jacobsen, I D; Tveit, A B; Espelid, I; Crossner, C G

    2016-09-01

    To study the prevalence, distribution and severity of dental erosion among 16-year-old adolescents in the Troms region of Norway. Study design: The participants were recruited through the Tromsø-study ("Fit Futures"), and 392 16-year-olds were examined for dental erosion using clinical intraoral photographs. Three calibrated clinicians used the Visual Erosion Dental Examination (VEDE) system to register and grade the dental erosive wear. More than one third (38%) of the participants showed dental erosion on at least one tooth surface, 18% were limited to the enamel, while 20% of the adolescents showed erosive wear extending into the dentine. The occlusal surfaces of the lower first molars, and the palatal surfaces of the maxillary incisors were the most often and most severely affected. Of the participants showing dental erosion, 93% exhibited "cuppings" on the molars, with 48% limited to the enamel and 52% extending into the dentine. The highest prevalence of "cuppings" (73%) was found on the first lower molars, especially the mesiobuccal cusp of the teeth. The prevalence and severity of dental erosion was found to be higher in male than in female participants (p dental erosion among adolescents in Troms and stress the importance of information, early and effective diagnostics and implementation of prevention strategies.

  10. Relationship between Risk Behavior for Eating Disorders and Dental Caries and Dental Erosion.

    Science.gov (United States)

    Brandt, Lorenna Mendes Temóteo; Fernandes, Liege Helena Freitas; Aragão, Amanda Silva; Aguiar, Yêska Paola Costa; Auad, Sheyla Márcia; de Castro, Ricardo Dias; Cavalcanti, Sérgio D'Ávila Lins Bezerra; Cavalcanti, Alessandro Leite

    2017-01-01

    The aim of this study was to evaluate whether there is an association between risk behavior for eating disorders (EDs) and dental erosion and caries. A controlled cross-sectional study was conducted in Brazil, involving 850 randomly selected female adolescents. After evaluating risk behavior for eating disorders through the Bulimic Investigatory Test of Edinburgh, 12 adolescents were identified with severe risk behavior for EDs and matched to 48 adolescents without such risk. Dental examinations, anthropometric measurements, and eating habits and oral hygiene were performed. Adolescents with high severity eating disorder condition were not more likely to show dental caries ( p = 0.329; OR = 2.2, 95% CI: 0.35-13.72) or dental erosion ( p = 0.590; OR = 2.33; 95% CI: 0.56-9.70). Adolescents with high body mass index (BMI) were five times more likely to have high severity eating disorder condition ( p = 0.031; OR = 5.1; 95% CI: 1.61-23.07). Therefore, high severity risk behavior for EDs was not significantly associated with dental caries and dental erosion. However, high BMI was a risk factor for developing eating disorders and should be an alert for individuals with this condition.

  11. Prevalence and associated factors of dental erosion in children and adolescents of a private dental practice.

    Science.gov (United States)

    Nahás Pires Corrêa, Maria Salete; Nahás Pires Corrêa, Fernanda; Nahás Pires Corrêa, José Paulo; Murakami, Christiana; Mendes, Fausto Medeiros

    2011-11-01

    BaCKGROUND. The prevalence of dental erosion seems to be rising in young populations, particularly among individuals of higher socioeconomic status. AIM. To assess the prevalence and associated factors of dental erosion in children and adolescents of a private dental practice. DESIGN. A total of 232 participants, aged 2-20 years, were examined. Dietary habits, oral hygiene, and medical data were collected from dental records. Logistic regression analyses were conducted. RESULTS. Dental erosion prevalence was of 25.43% and was highest on the occlusal surfaces (76%). Associated factors were: frequent consumption of soft drinks (OR = 2.33; 95% CI = 1.01-5.38) and candies (OR = 3.23; 95% CI = 1.25-8.32); and interaction between these two factors (OR = 3.95; 95% CI = 1.60-9.75). On anterior teeth, associated factors were: frequent consumption of fruits (OR = 2.53; 95% CI = 1.09-5.91); and age (OR = 1.07 95% CI = 1.01-1.14). Milk consumption was associated with a lower prevalence of dental erosion (OR = 0.40; 95% CI = 0.17-0.94). CONCLUSIONS.  A relatively high prevalence of erosion was found in association with frequent intake of soft drinks, candies, and fruits. The consumption of milk seemed to protect against dental erosion on anterior teeth. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

  12. Dental erosion among South Brazilian adolescents: A 2.5-year longitudinal study.

    Science.gov (United States)

    Brusius, C D; Alves, L S; Susin, C; Maltz, M

    2018-02-01

    This population-based longitudinal study investigated the incidence, progression and risk factors for dental erosion among South Brazilian adolescents. Eight hundred and one schoolchildren attending 42 public and private schools were clinically examined at 12 years of age; clinical examinations were repeated after 2.5 years (SD=0.3). After tooth cleaning and drying, permanent incisors and first molars were classified using the Basic Erosive Wear Examination (BEWE) scoring criteria. Questionnaires were used to collect data on socio-demographic characteristics, dietary habits, toothbrushing frequency and general health. Poisson regression analysis was used to assess the association between dental erosion incidence and explanatory variables, with adjusted incidence risk ratios (IRR) and 95% CI estimated. Among those who did not have dental erosion at baseline, 49 of 680 schoolchildren (7.1%; 95% CI=5.2-9.1) developed erosive lesions over the follow-up period. Among schoolchildren who had dental erosion at baseline, 31 of 121 (25.4%; 95% CI=17.6-33.3) had new or more severe lesions. Boys were more likely to develop dental erosion than girls (IRR=1.88; 95% CI=1.06-3.32). A moderate incidence of dental erosion was observed among South Brazilian adolescents, with boys being at higher risk. The high progression rate of 25% observed here is very concerning, and it should be taken in consideration when designing preventive strategies for dental erosion. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Dental erosion -- changing prevalence? A review of British National childrens' surveys.

    Science.gov (United States)

    Nunn, J H; Gordon, P H; Morris, A J; Pine, C M; Walker, A

    2003-03-01

    To investigate the change in the prevalence of dental erosion, over time, by a review of the data from the published national dental surveys of young people in the UK. A subsidiary objective was to investigate the relationship between erosion and possible associated risk factors. The review was based on cross-sectional prevalence studies incorporating a clinical dental examination and structured interviews. The data were collated from the 1993 UK childrens' dental health survey and the dental report of the two National Diet and Nutrition Surveys (NDNS) of children aged 1(1/2)-4(1/2) in 1992/3 and 4-18 years in 1996/7. The criteria used for data collection were comparable between the three different studies. Comparing the data from the different studies, the prevalence of erosion was seen to increase from the time of the childrens' dental health survey in 1993 and the NDNS study of 4-18-year-olds in 1996/7. There was a trend towards a higher prevalence of erosion in children aged between 3(1/2) and 4(1/2) and in those who consumed carbonated drinks on most days compared with toddlers consuming these drinks less often. Drinks overnight were associated with an increased prevalence of erosion. More 4-6-year-olds with reported symptoms of gastro-oesophageal reflux had erosion compared with symptom-free children. On multivariate analysis, the strongest independent association with erosion was geography, with children living in the North having twice the odds of having erosion compared with those in London and the South-east. Comparing prevalence data from cross-sectional national studies indicates that dental erosion increases between different age cohorts of young people over time. Dietary associations with erosion are present but weak. Similarly, there is an association apparent between erosion, symptoms of gastro-oesophageal reflux and socio-demographic variables such as region of domicile, social class, and receipt of social benefits.

  14. Dental erosion in groups of Yemeni children and adolescents and the modification of an erosion partial recording system

    OpenAIRE

    Al-Ashtal, Amin Mohsen Saleh; Johansson, Anders; Ridwaan, Omar; Johansson, Ann-Katrin

    2016-01-01

    Background: Dental erosion is a multifactorial oral health problem with an increasing prevalence among children and adolescents in many countries. Awareness of the condition among lay people is generally lacking, and methods for its clinical grading also need further improvements. Aim: The aims of this thesis was to investigate various aspects of dental erosion including prevalence and risk indicators, to evaluate the recording system used, and to assess the awareness of dental erosion in ...

  15. Dental approach to erosive tooth wear in gastroesophageal reflux ...

    African Journals Online (AJOL)

    Background: The duration of gastro-esophageal reflux disease (GERD), the frequency of reflux, the pH and type of acid, and the quality and quantity of saliva affect the severity of dental erosion due to GERD. Objective: To summarize the diagnostic protocol and treatment of dental erosion due to GERD. Methods: A Medline ...

  16. Prevalence of Dental Erosion among the Young Regular Swimmers in Kaunas, Lithuania

    Directory of Open Access Journals (Sweden)

    Andrius Zebrauskas

    2014-07-01

    Full Text Available Objectives: To determine prevalence of dental erosion among competitive swimmers in Kaunas, the second largest city in Lithuania. Material and Methods: The study was designed as a cross-sectional survey, with a questionnaire and clinical examination protocols. The participants were 12 - 25 year-old swimmers regularly practicing in the swimming pools of Kaunas. Of the total of 132 participants there were 76 (12 - 17 year-old and 56 (18 - 25 year-old individuals; in Groups 1 and 2, respectively. Participants were examined for dental erosion, using a portable dental unit equipped with fibre-optic light, compressed air and suction, and standard dental instruments for oral inspection. Lussi index was applied for recording dental erosion. The completed questionnaires focused on the common erosion risk factors were returned by all participants. Results: Dental erosion was found in 25% of the 12 - 17 year-olds, and in 50% of 18 - 25 years-olds. Mean value of the surfaces with erosion was 6.31 (SD 4.37. All eroded surfaces were evaluated as grade 1. Swimming training duration and the participants’ age correlated positively (Kendall correlation, r = 0.65, P < 0.001, meaning that older swimmers had practiced for longer period. No significant correlation between occurrence of dental erosion and the analyzed risk factors (gastroesophageal reflux disease, frequent vomiting, dry mouth, regular intake of acidic medicines, carbonated drinks was found in both study groups. Conclusions: Prevalence of dental erosion of very low degree was high among the regular swimmers in Kaunas, and was significantly related to swimmers’ age.

  17. Primary prevention of dental erosion by calcium and fluoride: a systematic review.

    Science.gov (United States)

    Zini, A; Krivoroutski, Y; Vered, Y

    2014-02-01

    Overviews of the current literature only provide summaries of existing relevant preventive strategies for dental erosion. To perform a systematic review according to the quantitative meta-analysis method of the scientific literature on prevention of dental erosion. The focused question will address primary prevention of dental erosion by calcium and fluoride. Randomized clinical trials (RCTs) regarding dental erosion prevention. The search included five databases: Embase, Cochrane database of systematic reviews, PubMed (MEDLINE), FDA publication and Berman medical library of the Hebrew University. The search included data in the English language, with effect on preventing dental erosion always presented as mean enamel loss and measured by profilometer. Statistical meta-analysis was performed by StatsDirect program and PEPI statistical software. Fixed- and random-effect models were used to analyse the data. Heterogeneity tests were employed to validate the fixed-effect model assumption. A total of 475 articles on dental erosion prevention were located. A four-stage selection process was employed, and 10 RCT articles were found to be suitable for meta-analysis. The number of studies on prevention of dental erosion maintaining standards of evidence-based dentistry remains insufficient to reach any definite conclusions. The focused questions of this review cannot be addressed according to the existing literature. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Morphology and structure of polymer layers protecting dental enamel against erosion.

    Science.gov (United States)

    Beyer, Markus; Reichert, Jörg; Sigusch, Bernd W; Watts, David C; Jandt, Klaus D

    2012-10-01

    Human dental erosion caused by acids is a major factor for tooth decay. Adding polymers to acidic soft drinks is one important approach to reduce human dental erosion caused by acids. The aim of this study was to investigate the thickness and the structure of polymer layers adsorbed in vitro on human dental enamel from polymer modified citric acid solutions. The polymers propylene glycol alginate (PGA), highly esterified pectin (HP) and gum arabic (GA) were used to prepare polymer modified citric acids solutions (PMCAS, pH 3.3). With these PMCAS, enamel samples were treated for 30, 60 and 120s respectively to deposit polymer layers on the enamel surface. Profilometer scratches on the enamel surface were used to estimate the thickness of the polymer layers via atomic force microscopy (AFM). The composition of the deposited polymer layers was investigated with X-ray photoelectron spectroscopy (XPS). In addition the polymer-enamel interaction was investigated with zeta-potential measurements and scanning electron microscopy (SEM). It has been shown that the profilometer scratch depth on the enamel with deposited polymers was in the range of 10nm (30s treatment time) up to 25nm (120s treatment time). Compared to this, the unmodified CAS-treated surface showed a greater scratch depth: from nearly 30nm (30s treatment time) up to 60nm (120s treatment time). Based on XPS measurements, scanning electron microscopy (SEM) and zeta-potential measurements, a model was hypothesized which describes the layer deposited on the enamel surface as consisting of two opposing gradients of polymer molecules and hydroxyapatite (HA) particles. In this study, the structure and composition of polymer layers deposited on in vitro dental enamel during treatment with polymer modified citric acid solutions were investigated. Observations are consistent with a layer consisting of two opposing gradients of hydroxyapatite particles and polymer molecules. This leads to reduced erosive effects of

  19. Dental erosion prevalence and associated risk indicators among preschool children in Athens, Greece.

    Science.gov (United States)

    Mantonanaki, Magdalini; Koletsi-Kounari, Haroula; Mamai-Homata, Eleni; Papaioannou, William

    2013-03-01

    The aims of the study were to investigate dental erosion prevalence, distribution and severity in Greek preschool children attending public kindergartens in the prefecture of Attica, Greece and to determine the effect of dental caries, oral hygiene level, socio-economic factors, dental behavior, erosion related medication and chronic illness. A random and stratified sample of 605 Greek preschool children was clinically examined for dental erosion using the Basic Erosive Wear Examination Index (ΒΕWE). Dental caries (dmfs) and Simplified Debris Index were also recorded. The data concerning possible risk indicators were derived by a questionnaire. Zero-inflated Poisson regression was generated to test the predictive effects of the independent variables on dental erosion. The prevalence of dental erosion was 78.8 %, and the mean and SE of BEWE index was 3.64 ± 0.15. High monthly family income was positively related to ΒΕWE cumulative scores [RR = 1.204 (1.016-1.427)], while high maternal education level [RR = 0.872 (0.771-0.986)] and poor oral hygiene level [DI-s, RR = 0.584 (0.450-0.756)] showed a negative association. Dental erosion is a common oral disease in Greek preschool children in Attica, related to oral hygiene and socio-economic factors. Programs aimed at erosion prevention should begin at an early age for all children.

  20. Association between Dental Erosion and Diet in Brazilian Adolescents Aged from 15 to 19: A Population-Based Study

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    Yêska Paola Costa Aguiar

    2014-01-01

    Full Text Available Dental erosion is a pathological condition resulting from the irreversible dissolution of the mineralized portion of the teeth, being recognized in modern society as an important cause of loss of tooth structure. The aim of this study was to assess the prevalence and its association with diet in Brazilian adolescents of Campina Grande, PB, Brazil. A population-based study was conducted on a stratified sample of 675 adolescents aged from 15 to 19 of both sexes using the index proposed by O'Sullivan. Dental examinations were performed by two calibrated dentists (kappa = 0.82. The significance level adopted was 5%. The prevalence of dental erosion was 21%, and the upper central incisors and lateral incisors were the most affected elements, with 50.5% and 40.2%, respectively. The buccal surface showed greater impairment (51.4% and 67.8% of teeth with dental erosion had more than half of the surface of affected area. Most damage was on the enamel (93.5%. There were no statistically significant differences between the occurrence of dental erosion and gender, age, socioeconomic status, self-reported ethnicity, and diet. There was high prevalence of dental erosion in its early stages among adolescents and there were no significant differences in the frequency of the consumption of foods and beverages and the presence of dental erosion.

  1. Association between dental erosion and diet in Brazilian adolescents aged from 15 to 19: a population-based study.

    Science.gov (United States)

    Aguiar, Yêska Paola Costa; dos Santos, Fábio Gomes; Moura, Eline Freitas de Farias; da Costa, Fernanda Clotilde Mariz; Auad, Sheyla Marcia; de Paiva, Saul Martins; Cavalcanti, Alessandro Leite

    2014-01-01

    Dental erosion is a pathological condition resulting from the irreversible dissolution of the mineralized portion of the teeth, being recognized in modern society as an important cause of loss of tooth structure. The aim of this study was to assess the prevalence and its association with diet in Brazilian adolescents of Campina Grande, PB, Brazil. A population-based study was conducted on a stratified sample of 675 adolescents aged from 15 to 19 of both sexes using the index proposed by O'Sullivan. Dental examinations were performed by two calibrated dentists (kappa = 0.82). The significance level adopted was 5%. The prevalence of dental erosion was 21%, and the upper central incisors and lateral incisors were the most affected elements, with 50.5% and 40.2%, respectively. The buccal surface showed greater impairment (51.4%) and 67.8% of teeth with dental erosion had more than half of the surface of affected area. Most damage was on the enamel (93.5%). There were no statistically significant differences between the occurrence of dental erosion and gender, age, socioeconomic status, self-reported ethnicity, and diet. There was high prevalence of dental erosion in its early stages among adolescents and there were no significant differences in the frequency of the consumption of foods and beverages and the presence of dental erosion.

  2. Acquired pellicle as a modulator for dental erosion.

    Science.gov (United States)

    Vukosavljevic, Dusa; Custodio, William; Buzalaf, Marilia A R; Hara, Anderson T; Siqueira, Walter L

    2014-06-01

    Dental erosion is a multifactorial condition that can result in the loss of tooth structure and function, potentially increasing tooth sensitivity. The exposure of enamel to acids from non-bacterial sources is responsible for the progression of erosion. These erosive challenges are counteracted by the anti-erosive properties of the acquired pellicle (AP), an integument formed in vivo as a result of selective adsorption of salivary proteins on the tooth surface, containing also lipids and glycoproteins. This review provides an in-depth discussion regarding how the physical structure of the AP, along with its composition, contributes to AP anti-erosive properties. The physical properties that contribute to AP protective nature include pellicle thickness, maturation time, and site of development. The pellicle contains salivary proteins embedded within its structure that demonstrate anti-erosive properties; however, rather than individual proteins, protein-protein interactions play a fundamental role in the protective nature of the AP. In addition, dietary and synthetic proteins can modify the pellicle, enhancing its protective efficiency against dental erosion. The salivary composition of the AP and its corresponding protein-profile may be employed as a diagnostic tool, since it likely contains salivary biomarkers for oral diseases that initiate at the enamel surface, including dental erosion. Finally, by modifying the composition and structure of the AP, this protein integument has the potential to be used as a target-specific treatment option for oral diseases related to tooth demineralization. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Relationship between dental erosion and respiratory symptoms in patients with gastro-oesophageal reflux disease.

    Science.gov (United States)

    Wang, Geng-Ru; Zhang, Hui; Wang, Zhong-Gao; Jiang, Guang-Shui; Guo, Cheng-Hao

    2010-11-01

    Both dental erosion and respiratory symptoms are extra-oesophageal manifestations of gastro-oesophageal reflux disease (GERD). The aim of this study was to determine whether dental erosion was correlated with respiratory symptoms in GERD patients. 88 GERD patients were recruited and assigned to three groups mainly according to the frequency of respiratory symptoms: Group I: never; Group II: occasional (1-2 days a week or less); Group III: frequent (3-5 days a week or more). All patients underwent medical evaluations, including medical history, questionnaire answering and alimentary tract examinations. Dental examinations were carried out on these patients and 36 healthy controls. Dental erosions were measured by modified method of Smith and Knight Tooth Wear Index (TWI). Location and severity of dental erosion were recorded. The prevalence of dental erosion in Group III (64.52%) was higher (pdental erosion with TWI scores ranging from 1 to 4. Though proportion of dental erosion with Score 2 (7/20) in Group III was higher than that in Group I (2/11) and Group II (3/12), there was no statistical significance in the proportions of erosion scores among three patient groups. Correlation coefficient between airway symptoms and scores of dental erosion was 0.231 (perosion of upper incisor was seen in 8 persons (72.7%) in Group I, 9 persons (75%) in Group II and 16 persons (80%) in Group III (p>0.05). Labial erosion of upper incisors was found in 1 person in Groups I and II respectively and 4 persons in Group III. All patients with labial erosion on upper incisors had palatal erosion, except 1 patient in Group III. In GERD patients, dental erosions are more prevalent in patients with frequent respiratory symptoms than those in patients with occasional and without respiratory symptoms. Palatal erosion of upper incisor is the main manifestation in patients. Acid reflux is the main causative factor of dental erosion in GERD patients with airway symptoms. Copyright © 2010

  4. Dental erosion: causes, diagnostics and treatment.

    OpenAIRE

    Cecilia Sosa-Puente; Juan Solís-Soto; Norma Cruz-Fierro; Sonia López-Villarreal; Sergio Nakagoshi-Cepeda

    2014-01-01

    Resumen: A pesar de ser un tópico altamente examinado, es difícil encontrar estudios que esclarezcan la problemática de la erosión dental. En este trabajo se analizó en la literatura los agentes que desencadenan la erosión dental, los principales métodos de diagnosis, los tratamientos más empleados en la actualidad y la interrelación con los materiales dentales. La etiología de la erosión es multifactorial incluyendo elementos ácidos, desórdenes alimenticios y reflujo gastroesofágico. Sin em...

  5. Dental erosion in groups of Yemeni children and adolescents and the modification of an erosion partial recording system.

    Science.gov (United States)

    Al-Ashtal, Amin; Johansson, Anders; Omar, Ridwaan; Johansson, Ann-Katrin

    2017-07-01

    The prevalence of dental erosion is rising especially among children and adolescents and its grading needs further investigation. To determine the prevalence and severity of dental erosion in groups of Yemeni children and adolescents, and to clinically compare an erosion partial recording system (EPRS) with a proposed modified-simplified version (EPRS-M). Of 6163 individuals aged 5-6, 13-14 and 18-19 years, 911 were randomly selected, of which 668 participated in the study. Dental erosion was graded using EPRS. EPRS-M was proposed, and its sensitivity and specificity was calculated in relation to EPRS. Prevalence of erosion extending into dentine on at least one tooth was 6.8% among 5- to 6-year-olds, 3.0% among 13- to 14-year-olds and 14.6% among 18- to 19-year olds. The highest prevalence was 19.2% among girls aged 18-19 years which was significantly higher than boys (10.4%) in the same age group (P = 0.044). Sensitivity and specificity for EPRS-M in relation to EPRS were 85.7% and 100% for primary teeth, and 84.1% and 100% for permanent teeth. Dental erosion was common among children and older teenagers and highest among older girls but less common among younger teenagers. The tested accuracy of EPRS-M qualifies it to be used as an initial quick detection tool in future dental erosion research. © 2016 The Authors. International Journal of Paediatric Dentistry published by BSPD, IAPD and John Wiley & Sons Ltd.

  6. Prevalence of dental erosion and association with lifestyle factors in Swedish 20-year olds.

    Science.gov (United States)

    Isaksson, Helén; Birkhed, Dowen; Wendt, Lill-Kari; Alm, Anita; Nilsson, Mats; Koch, Göran

    2014-08-01

    To investigate the prevalence, distribution and severity of dental erosion and its association with lifestyle, oral and general health in young adults. Four hundred and ninety-four individuals, 20-years of age, participated. Dental erosion in molars and maxillary incisors was evaluated. Caries, plaque and gingivitis were registered. Saliva samples were taken and the subjects were interviewed about behavioural and dietary habits and oral and general health. Body mass index (BMI) was calculated. The individuals were sub-divided into two groups according to the presence and absence of dental erosion: within the group with erosion was a sub-group of individuals with extensive erosion. Of the individuals 25% had no erosion, 75% had erosion and 18% had extensive erosion. Erosion was found in molars in 74% of the individuals and on buccal and palatal surfaces in maxillary incisors in 4% and 7%, respectively. Cupping was seen in 65% of individuals and severe erosion in molars in 1.6%. Compared to subjects with no erosion, those with extensive erosion had a higher consumption of soft drinks (p = 0.05), caries prevalence (p erosion had higher caries prevalence (p erosion. Swedish young adults have a high prevalence of dental erosion, but the level of severe erosion is low. The study disclosed a relationship between dental erosion and behavioural factors, oral health and BMI.

  7. Incidence and Pattern of Dental Erosion in Gastroesophageal Reflux Disease Patients.

    Science.gov (United States)

    Ramachandran, Anupama; Raja Khan, Sulthan Ibrahim; Vaitheeswaran, Nandinee

    2017-11-01

    Gastroesophageal reflux disease (GERD) is a very common condition whose consequences of are localized not only in the esophagus; extra-esophageal involvement has frequently been reported. The aim of the study is to examine the incidence and pattern of dental erosion in GERD patients. A total of 50 patients were recruited in this study (control -25 and GERD -25). All participants diagnosed having GERD by the endoscopic examination by their gastroenterologist are included. The patients were examined for dental erosion and will be quantified using Basic erosive wear examination index. The results showed that the incidence of dental erosion was 88% as compared to 32% in the control group which was found to be statistically significant.

  8. Diagnóstico y epidemiología de erosión dental Diagnosis and epidemiology of dental erosion

    Directory of Open Access Journals (Sweden)

    Maria Claudia Fajardo Santacruz

    2011-08-01

    Full Text Available La erosión dental es la pérdida localizada, crónica y patológica de tejido duro dental. Ésta es causada por soluciones químicas las cuales entran en contacto con los dientes. La apariencia de los dientes erosionados es suave, sedosa y brillante, a veces mate, la superficie del esmalte tiene una ausencia de periquimatíes y esmalte intacto en el margen gingival. Se ha hipotetizado que la banda de esmalte preservado a lo largo del margen vestibular y lingual pudiera ser debido a que algunos remanentes de placa podían actuar como una barrera de difusión para los ácidos. Un diagnóstico temprano de este daño del tejido duro dental es de importancia clínica. El objetivo de este artículo es mostrar algunos aspectos básicos de erosión dental en términos de diagnóstico y epidemiología. Este documento enfatiza sobre factores de riesgo extrínsecos los cuales son discutidos con respecto a su relevancia para el desarrollo de erosión dental. Salud UIS 2011; 43 (2: 179-189Dental erosion is a pathologic, chronic, localized loss of dental hard tissue. It is caused by chemical solutions which come into contact with the teeth. The appearance of eroded teeth is smoothing, silky-glazed, sometimes dull, the enamel surface has an absence of perikymata and intact enamel on the gingival margin. It has been hypothesized that the preserved enamel band along the oral and facial gingival margin could be due to some plaque remnants could act as a diffusion barrier for acids. Early diagnosis of this damage of dental hard tissue is of clinical importance. The aim of this article is to show some basic aspects of dental erosion in terms of diagnosis and epidemiology. This paper emphasize on extrinsic risk factors which are discussed with respect to their relevance for the development of dental erosion. Salud UIS 2011; 43 (2: 179-189

  9. The prevalence of dental erosion in 5-year-old preschoolers in Sharjah, United Arab Emirates.

    Science.gov (United States)

    Gopinath, Vellore Kannan

    2016-01-01

    The aim of this study was to determine the percentage of 5-year-old preschoolers in Sharjah, affected by dental erosion and to assess the predictors. A total of 403 5-year-old children were examined of which 48.14% (n = 194) were boys and 51.86% (n = 209) were girls; 31.27% (n = 126) were Emirati and 68.73% (n = 277) were non-Emirati Arabs. Examination of dental erosion was confined to palatal surfaces of maxillary incisors using the erosion index described in the UK National Survey of Children's Dental Health, 1993. Dental caries was charted using the World Health Organization 1997 criteria. In the sample of 403 5-year-old preschoolers examined, dental erosion was apparent in 237 (58.80%) children, with 55.09% showing the dissolution of enamel and 3.72% exhibiting exposed dentin. Predictors of dental erosion as determined by logistic regression concluded that compared to Emirati citizens other Arab nationalities have 0.27 times the odds (95% confidence interval [CI] =0.18-0.42) of having tooth erosion (P United Arab Emirates, were affected by dental erosion. Caries experience and consumption of acidic drinks were associated with dental erosion.

  10. Is histologic esophagitis associated with dental erosion: a cross-sectional observational study?

    Science.gov (United States)

    Friesen, Lynn Roosa; Bohaty, Brenda; Onikul, Robin; Walker, Mary P; Abraham, Caren; Williams, Karen B; Cocjin, Jose T; Cocjin, Eileen L; Friesen, Craig A

    2017-08-10

    Gastroesophageal reflux disease (GERD) affects 15-25% of children and adolescents in the United States. The diagnosis of GERD in children is complex as reported symptoms or symptom profiles have been found to be unreliable. Frequently, the diagnosis must be confirmed by objective tests such as pH monitoring or histological evidence of esophagitis on an esophageal biopsy. Dental erosion has been shown to be associated with GERD as an atypical complication and has the potential to be a marker of GERD. The purposes of this study were to compare the frequency and patterns of dental erosion in children and adolescents with and without histologic esophagitis. Twenty-five subjects were recruited from patients scheduled for an upper gastrointestinal endoscopy. Information regarding potential GERD symptoms, food habits, and dental hygiene habits were obtained. Intra-oral photographs were taken, and a dental exam for erosion was performed. The results of a standard biopsy taken from the lower third of the esophagus during an endoscopy were used to divide subjects into either the control group or the GERD group (i.e. those with histologic esophagitis). Twenty-two subjects yielded 586 evaluable teeth. No significant difference was found between frequency or erosion patterns of those with and without histologic esophagitis. Dental erosions were more frequent in primary teeth. Dental erosions do not appear to be associated with histologic esophagitis indicative of GERD.

  11. On inhibition of dental erosion.

    Science.gov (United States)

    Rölla, Gunnar; Jonski, Grazyna; Saxegaard, Erik

    2013-11-01

    To examine the erosion-inhibiting effect of different concentrations of hydrofluoric acid. Thirty-six human molars were individually treated with 10 ml of 0.1 M citric acid for 30 min (Etch 1), acid was collected and stored until analysis. The teeth were randomly divided into six groups and then individually treated with 10 ml of one of six dilutions (from 0.1-1%) of hydrofluoric acid. The teeth were then again treated with citric acid (Etch 2). The individual acid samples from Etch 1 and 2 were analyzed for calcium by flame atomic absorption spectroscopy and difference in calcium loss was calculated. The highest erosion inhibiting effect was obtained in groups with the highest concentrations of hydrofluoric acid, where the pH was lowest, below pKa of 3.17, thus the hydrofluoric acids being mainly in an undissociated state. Diluted hydrofluoric acid is present in aqueous solution of SnF2 and TiF4 (which are known to inhibit dental erosion): SnF2 + 3H2O = Sn(OH)2 + 2HF + H2O and TiF4 + 5H2O = Ti(OH)4 + 4HF + H2O. It is also known that pure, diluted hydrofluoric acid can inhibit dental erosion. Teeth treated with hydrofluoric acid are covered by a layer of CaF2-like mineral. This mineral is acid resistant at pH acid resistant mineral, initiated by tooth enamel treatment with hydrofluoric acid. Hydrofluoric acid is different in having fluoride as a conjugated base, which provides this acid with unique properties.

  12. An investigation into the dental health of children with obesity: an analysis of dental erosion and caries status.

    Science.gov (United States)

    Tong, H J; Rudolf, M C J; Muyombwe, T; Duggal, M S; Balmer, R

    2014-06-01

    To investigate whether children with obesity experienced more erosion and caries than children with normal weight. This study involved children aged 7-15 years. The study and control group comprised 32 children with BMI > 98th centile and 32 healthy children with normal BMI-for-age, respectively. O'Sullivan Erosion Index and WHO Caries Index were used in the examination of erosion and caries, respectively. Stimulated salivary flow rate, buffering capacity, Streptococcus mutans and lactobacilli counts (CFU/ml) were evaluated. A cross-sectional questionnaire survey was employed to collect information on participant's demographic background, oral health history and habits, and utilisation of dental care services. Children with obesity were more likely to have erosion than healthy children (p erosion in terms of severity (p erosion (OR 0.32, 95 % CI 0.012-0.082). Gender had no effect on erosion. There were no statistically significant differences in the DMFT, saliva profiles or questionnaire responses between the groups. Children with obesity may have high risk of dental erosion, but do not necessarily have higher risk of dental caries than children with normal weight.

  13. Dental erosion due to abuse of illicit drugs and acidic carbonated beverages.

    Science.gov (United States)

    Bassiouny, Mohamed A

    2013-01-01

    Consumption of illicit drugs and the abusive intake of acidic carbonated beverages (particularly soda) often are associated with similar types of damage to the human dentition, the most common of which is dental erosion. The dentitions of individuals who are addicted to methamphetamines or crack cocaine can be misdiagnosed as dental caries rather than generalized dental erosion, a condition that also is associated with chronic excessive consumption of soda. Failing to identify the causative etiology could lead to a wrongful diagnosis that could in turn adversely affect treatment planning and misdirect a specified prevention protocol. This article seeks to identify the unique clinical features of each one of these conditions, highlight the resemblances between them, and recognize the unambiguous differences in their fundamental characteristics. Three representative cases-involving a methamphetamine user, a crack cocaine addict, and an avid consumer of diet soda-are presented. In each case, the patient has admitted to the cause of their poor oral health. The dental, oral, and paraoral manifestations of each case are documented and differentiated from one another, and the factors that contributed to the associated disease process are discussed.

  14. An Industrial Dental-Erosion by Chromic Acid: A Case Report

    Science.gov (United States)

    Dülgergil, Ç. Türksel; Erdemir, Ebru Olgun; Ercan, Ertuḡrul; Erdemir, Ali

    2007-01-01

    A case of uncommon occupational dental erosion was reported in an individual who had worked in the war industry for twenty years. This occupation involved daily, at least 8 hours, inhalation of chromic acid being used for cleaning of barrel of cannons. The erosion manifested as dental sensitivity with excessive cervical erosion even with pulpal exposure in certain teeth. Moreover, due to the adverse effect of the chemical against to gingival and/or periodontal tissues, the lesions were extremely harmful with respect to the exposed root-cementum. After proper periodontal therapy, cervical lesions were treated conservatively with a compomer based restorative material without cavity preparation. Although today it is not common due to the well-controlled working conditions, occupational combined dental and medical problems via airborne fumes and/or elements can be seen at workers in chemical factories. A cumulative biohazardous effect is generally seen as not only medical but also dental disorders. PMID:19212488

  15. EFFECTS OF PROTON PUMP INHIBITORS ON DENTAL EROSIONS CAUSED BY GASTROESOPHAGEAL REFLUX DISEASE

    Directory of Open Access Journals (Sweden)

    Andrei Vasile OLTEANU

    2015-12-01

    Full Text Available Background: Numerous studies worldwide have assessed the association between dental erosions or other related oral manifestations, and the gastroesophageal reflux disease (GERD. Nowadays, one of the main therapeutic resources of GERD is represented by proton pump inhibitors (PPIs. Adequate salivary secretions and flow are considered mandatory for the protection of both teeth and esophageal mucosa. The aim of the present study was to evaluate the possible correlation between GERD treatment options and subsequent control of oral manifestation, taking as premises that either PPIs or dietary and lifestyle changes may control oral patterns of GERD by acting on salivary secretions. Methods: 48 clinically diagnosed GERD adult patients with oral manifestations, mainly erosions, were included in the study, none of which showing alarming symptoms that would require further gastroenterologic examination. Oral examination evaluated the DMF (decayed, missing, filled and OHI-S (Simplified Oral Hygiene indices. Salivary flow was evaluated by the Saxon test. 25 patients were prescribed dietary and lifestyle measures and PPIs (omeprazole – 20 mg, whereas 23 patients were managed only through dietary and lifestyle modifications. General assessment was performed at the time of diagnosis and 4 weeks afterwards. Results: No significant differences as to the DMF index, OHI-S index or Saxon test were found over the 4 weeks management between the groups. Conclusions: Oral manifestation of GERD may be caused by impaired salivary secretions and flow, otherwise no - positive or negative - effect could be secondary to PPI therapy. Accordingly, complex oral rehabilitation of GERD patients and collaboration between gastroenterologists and dentists should be promoted.

  16. Dental Erosion and its Associated Factors In 11-16-Year Old School Children.

    Science.gov (United States)

    Kirthiga, M; Poornima, P; Praveen, R; Sakeena, B; Disha, P

    2015-01-01

    Dental erosion currently stands as a great challenge for the clinician, regarding the diagnosis, identification of the etiological factors, prevention and execution of an adequate treatment. To evaluate the prevalence, severity, and associated factors on dental erosion in 11-16-years old. A cross sectional study was conducted among 2000 school children who were randomly selected. A questionnaire was given to the children that included personal demographic details and habit of consuming acidic foods and drinks. An index specific for dental erosion given by O Sullivan was used to assess every affected tooth. The values were subjected to chi-square test and multivariate logistic regression analysis. The prevalence of dental erosion was found to be 1.4%. Females (1.6%) were slightly more affected than males (1.3%). Public school children (2.1%) were found to be affected a little more than private children (0.7%). Chi square test showed significant association between type of school and erosion prevalence (p = 0.015). Most commonly affected teeth were lateral incisor (59.72%). The prevalence of dental erosion was found to be low when compared to various studies done all over the world.

  17. Gastroesophageal reflux, dental erosion, and halitosis in epidemiological surveys: a systematic review.

    Science.gov (United States)

    Marsicano, Juliane A; de Moura-Grec, Patrícia G; Bonato, Rafaela C S; Sales-Peres, Matheus de Carvalho; Sales-Peres, Arsenio; Sales-Peres, Sílvia Helena de Carvalho

    2013-02-01

    In published studies, it has been suggested that dental wear is associated with gastroesophageal reflux disease (GERD). This systematic review was carried out to evaluate the association of GERD, dental erosion, and halitosis and to compare the indices adopted in epidemiological surveys. The Medline database (until October, 2011) was searched systematically to identify studies evaluating the prevalence of oral alterations, such as dental erosion and halitosis, in patients with GERD symptoms. Two reviewers analyzed all reports and the selected studies were evaluated according to the quality of evidence, using the validated Newcastle-Ottawa Quality Assessment Scale. Full-text copies of a total of 32 publications were obtained in duplicate. Sixteen publications were identified among the citations in the Bibliographic lists of studies that fulfilled the exclusion/inclusion criteria and quality of evidence. The relationship between dental erosion and GERD patients was significant in only seven studies. According to three studies, halitosis could be one of several extraesophageal symptoms or manifestations in GERD patients. In one study, it was found that the mucosa of GERD patients was significantly more acidic in comparison with that of the control group. This systematic review showed that there is a relationship between GERD and oral diseases (dental erosion and halitosis). The epidemiological surveys used different indices to analyze GERD and dental erosion. Further research could investigate the best method for assessing the two diseases.

  18. Dental erosion--an overview with emphasis on chemical and histopathological aspects.

    Science.gov (United States)

    Lussi, A; Schlueter, N; Rakhmatullina, E; Ganss, C

    2011-01-01

    The quality of dental care and modern achievements in dental science depend strongly on understanding the properties of teeth and the basic principles and mechanisms involved in their interaction with surrounding media. Erosion is a disorder to which such properties as structural features of tooth, physiological properties of saliva, and extrinsic and intrinsic acidic sources and habits contribute, and all must be carefully considered. The degree of saturation in the surrounding solution, which is determined by pH and calcium and phosphate concentrations, is the driving force for dissolution of dental hard tissue. In relation to caries, with the calcium and phosphate concentrations in plaque fluid, the 'critical pH' below which enamel dissolves is about 5.5. For erosion, the critical pH is lower in products (e.g. yoghurt) containing more calcium and phosphate than plaque fluid and higher when the concentrations are lower. Dental erosion starts by initial softening of the enamel surface followed by loss of volume with a softened layer persisting at the surface of the remaining tissue. Dentine erosion is not clearly understood, so further in vivo studies, including histopathological aspects, are needed. Clinical reports show that exposure to acids combined with an insufficient salivary flow rate results in enhanced dissolution. The effects of these and other interactions result in a permanent ion/substance exchange and reorganisation within the tooth material or at its interface, thus altering its strength and structure. The rate and severity of erosion are determined by the susceptibility of the dental tissues towards dissolution. Because enamel contains less soluble mineral than dentine, it tends to erode more slowly. The chemical mechanisms of erosion are also summarised in this review. Special attention is given to the microscopic and macroscopic histopathology of erosion. Copyright © 2011 S. Karger AG, Basel.

  19. Tooth erosion awareness in a Brazilian dental school.

    Science.gov (United States)

    Hermont, Ana Paula; Oliveira, Patricia A D; Auad, Sheyla M

    2011-12-01

    The aim of this cross-sectional study was to assess awareness and attitudes related to tooth erosion among dental students, patients, and faculty members in a Brazilian dental school. Data were collected by means of a self-applied questionnaire that was distributed among 298 participants. The response rate was 89.6 percent. Chi-square and Fisher's exact tests were used for statistical analysis (perosion (72.9 percent), with lower percentages among the patients (perosion (p=0.004). Almost 30 percent of the students did not know if they had had a patient with erosion, and 73.1 percent reported they were not advised by their clinical supervisor to examine their patients for tooth erosion (p=0.138). Concerning the faculty, 23.6 percent of them along with 61.5 percent of the students did not feel prepared to diagnose the condition (perosion (89.6 percent). Knowledge about tooth erosion was not as widely evident as it should be in this sample, suggesting the need for better understanding and communication in this important area of oral health care.

  20. Dental erosion among children aged 3-6 years and its associated indicators.

    Science.gov (United States)

    Tao, Dan-Ying; Hao, Gu; Lu, Hai-Xia; Tian, Yu; Feng, Xi-Ping

    2015-01-01

    To analyze the status quo of dental erosion in 3- to 6-year-old children in Shanghai. A stratified, cluster, multistage random sampling methods was applied to 3- to 6-year-old children in Shanghai in 2012. Both questionnaire and clinical oral examination were performed in the survey. The questionnaire included general information, such as age, gender, parental education, dietary habit, oral health behavior, general medical health, and socioeconomic status. The clinical examination focused on the eroded tooth surface and dental erosion extent. SPSS v19.0 software package was utilized for statistical analysis. A total of 1,837 children aged 3-6 years were randomly selected in Shanghai. The overall dental erosion prevalence was 15.1 percent. Among different age groups, a relatively high prevalence of 17.1 percent was found in the 4-year-old group, and a relatively low prevalence of 12.0 percent was observed in the 3-year-old group. Surprisingly, there was no significant difference among the four age groups. The occurrence of dental erosion was influenced by habits of vinegar/coffee/tea consumption, mother's educational background, birthplace, and regurgitation (P dental erosion prevalence in 3- to 6-year-old children in Shanghai appears to be close to that of other Chinese provinces as well as that observed in most of surveys carried out in different parts of the world. Efforts should be made to raise public awareness about the disease. Moreover, further studies targeted to explore the relationship between dental erosion and risk factors are needed. It is also necessary to establish a unified diagnostic standard for future epidemiological investigations. © 2015 American Association of Public Health Dentistry.

  1. Association between dental erosion and possible risk factors: A hospital-based study in gastroesophageal reflux disease patients

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    Vamsi Krishna Reddy

    2016-01-01

    Full Text Available Introduction: Gastroesophageal reflux disease (GERD is a condition, with a prevalence of up to 10–20% in the general population. GERD may involve damage to the oral cavity, and dental erosion may occur with a higher frequency. Aim: To estimate the prevalence of dental erosion in GERD patients and to evaluate the association between dental erosion and possible risk factors. Materials and Methods: The study was conducted in the Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow among patients attending outpatient department between June and August 2014. The study group comprised 91 subjects with GERD and 114 subjects without GERD. Information regarding symptoms of GERD, medicines, any chronic disease, and dietary habits were recorded. Dental examination was done to assess the presence or absence of dental erosions and its severity was measured using O'Sullivan Index (2000. Statistical analysis was done using Mann–Whitney U-test and Kruskal–Wallis test. Results: Of 91 GERD patients, 87 (95.6% patients had dental erosion. In both groups, association between frequent intake of fruit juice, carbonated drinks, milk, yoghurt, fruits, and tea/coffee with occurrence of dental erosion were statistically significant (P < 0.05. In GERD patients, association between intake of milk and occurrence of dental erosion were statistically significant (P < 0.05. Association of medication with dental erosion was found to be statistically significant (P < 0.05. Chronic diseases like diabetes and asthma were also found to be statistically significant with dental erosion (P < 0.05. Conclusion: This study showed that GERD patients were at increased risk of developing dental erosion compared to controls.

  2. Dental Erosion and Dentin Hypersensitivity among Adult Asthmatics and Non-asthmatics Hospital-based: A Preliminary Study.

    Science.gov (United States)

    Farag, Zahra Hassan Abdelaziz; Awooda, Elhadi Mohieldin

    2016-01-01

    Asthma is a chronic inflammatory condition affecting the airways leading to spasm and swelling of the airways. The medications taken for the treatment of asthma can result in dental erosion and dentin hypersensitivity. The aims of this study were to investigate the severity of dental erosion amongst adult asthmatics according to: gender, type and duration of medication taken and to compare dental erosion and dentin hypersensitivity between asthmatics and non-asthmatics. Comparative, cross-sectional hospital based study among 40 asthmatics (M=15 & F=25) and 40 non-asthmatics (M=18 & F=22) in the age range of 18-60 year selected purposefully from Al-Shaab Teaching Hospital in Khartoum city. The Basic Erosive Wear Index was used for dental erosion assessment. Dentine hypersensitivity was determined by giving ice cold water and rated using the Visual Analogue Scale. Chi-square and Student's t-test were used for statistical analysis with P value ≤.05. There was an association between severity of dental erosion and presence of asthma (P=0.03), where asthmatics had a higher degree of erosion (moderate and severe) and non-asthmatics a lower degree. No significant association was found between dental erosion and gender, type and duration of medication among asthmatics group. A statistically significant difference was revealed in the degree of dentin hypersensitivity (P=0.00) among asthmatics (35.13%) and non-asthmatics (14.13%). Asthmatic patients had a higher degree of dental erosion and dentin hypersensitivity compared to non-asthmatics. Among asthmatic patients there was no association between severity of dental erosion and gender, type and duration medication was taken for.

  3. Gastro-oesophageal reflux is common in oligosymptomatic patients with dental erosion: A pH-impedance and endoscopic study.

    Science.gov (United States)

    Wilder-Smith, Clive H; Materna, Andrea; Martig, Lukas; Lussi, Adrian

    2015-04-01

    Dental erosion is a complication of gastro-oesophageal reflux disease (GORD) according to the Montreal consensus statement. However, GORD has not been comprehensively characterized in patients with dental erosions and pH-impedance measures have not been reported. Characterize GORD in patients with dental erosions using 24-h multichannel intraluminal pH-impedance measurements (pH-MII) and endoscopy. This single-centre study investigated reflux in successive patients presenting to dentists with dental erosion using pH-MII and endoscopy. Of the 374 patients, 298 (80%) reported GORD symptoms reflux episodes were 71 (63-79), 43 (38-49) and 31 (26-35), respectively. Of the reflux episodes, 19% (17-21) reached the proximal oesophagus. In 241 (69%) patients reflux was abnormal using published normal values for acid exposure time and reflux episodes. No significant associations between the severity of dental erosions and any reflux variables were found. The presence of GORD symptoms and of oesophagitis or a hiatal hernia was associated with greater reflux, but not with increased dental erosion scores. Significant oligosymptomatic gastro-oesophageal reflux occurs in the majority of patients with dental erosion. The degree of dental erosion did not correlate with any of the accepted quantitative reflux indicators. Definition of clinically relevant reflux parameters by pH-MII for dental erosion and of treatment guidelines are outstanding. Gastroenterologists and dentists need to be aware of the widely prevalent association between dental erosion and atypical GORD.

  4. Dental caries and erosion status of 12-year-old Hong Kong children.

    Science.gov (United States)

    Zhang, Shinan; Chau, Alex Mh; Lo, Edward Cm; Chu, Chun-Hung

    2014-01-08

    This study aimed to assess the dental caries and erosion status of 12-year-old Hong Kong children and study the determinants of dental caries and dental erosion of these children. The survey was performed from 2011 to 2012 with ethics approval. Stratified random sampling was adopted to select 12-year-old children in 7 primary schools in Hong Kong. The participating parents were asked to complete a self-administered questionnaire concerning their children's diet and oral health habits. The children were examined for caries status with WHO criteria by 3 calibrated examiners. Detection of dental erosion followed Basic Erosive Wear Examination (BEWE) criteria. A total of 704 children were recruited and 600 (316 boys, 53%) participated in the survey. There were 124 children (21%) with caries experience (DMFT > 0) and their DMFT was 0.34 ± 0.76. About half of their decay was unfilled (DT = 0.16 ± 0.52) The DMFT of girls and boys were 0.45 ± 0.89 and 0.23 ± 0.61, respectively (p = 0.001). Girls also had a higher DT (0.21 ± 0.62 compared with 0.11 ± 0.41, p = 0.013) and FT than boys (0.23 ± 0.63 compared with 0.12 ± 0.44, p = 0.016). Most children (75%) had at least some sign of erosion (BEWE > 0), but no severe erosion (BEWE = 3). Logistic regression showed girls who consumed soft drinks and took vitamin C supplements had higher caries risk. Dental erosion was more severe among the children who had caries experience and consumed fruit juice. The 12-year-old Hong Kong children had low caries experience, and almost half of the decay was left untreated. Although severe erosion was not found, many children had early signs of erosion.

  5. Full-mouth minimally invasive adhesive rehabilitation to treat severe dental erosion: a case report.

    Science.gov (United States)

    Vailati, Francesca; Vaglio, Giovanna; Belser, Urs Christoph

    2012-02-01

    Dental erosion is increasing, and only recently are clinicians starting to acknowledge the problem. A prospective clinical trial investigating which therapeutic approach must be undertaken to treat erosion and when is under way at the University of Geneva (Geneva Erosion Study). All patients affected by dental erosion who present with signs of dentin exposure are immediately treated using only adhesive techniques. In this article, the full-mouth adhesive rehabilitation of one of these patients affected by severe dental erosion (ACE class IV) is illustrated. By the end of the therapy, a very pleasing esthetic outcome had been achieved (esthetic success), all of the patient's teeth maintained their vitality, and the amount of tooth structure sacrificed to complete the adhesive full-mouth rehabilitation was negligible (biological success).

  6. Gastro-oesophageal reflux is common in oligosymptomatic patients with dental erosion: A pH-impedance and endoscopic study

    Science.gov (United States)

    Materna, Andrea; Martig, Lukas; Lussi, Adrian

    2015-01-01

    Background Dental erosion is a complication of gastro-oesophageal reflux disease (GORD) according to the Montreal consensus statement. However, GORD has not been comprehensively characterized in patients with dental erosions and pH-impedance measures have not been reported. Objectives Characterize GORD in patients with dental erosions using 24-h multichannel intraluminal pH-impedance measurements (pH-MII) and endoscopy. Methods This single-centre study investigated reflux in successive patients presenting to dentists with dental erosion using pH-MII and endoscopy. Results Of the 374 patients, 298 (80%) reported GORD symptoms reflux episodes were 71 (63–79), 43 (38–49) and 31 (26–35), respectively. Of the reflux episodes, 19% (17–21) reached the proximal oesophagus. In 241 (69%) patients reflux was abnormal using published normal values for acid exposure time and reflux episodes. No significant associations between the severity of dental erosions and any reflux variables were found. The presence of GORD symptoms and of oesophagitis or a hiatal hernia was associated with greater reflux, but not with increased dental erosion scores. Conclusions Significant oligosymptomatic gastro-oesophageal reflux occurs in the majority of patients with dental erosion. The degree of dental erosion did not correlate with any of the accepted quantitative reflux indicators. Definition of clinically relevant reflux parameters by pH-MII for dental erosion and of treatment guidelines are outstanding. Gastroenterologists and dentists need to be aware of the widely prevalent association between dental erosion and atypical GORD. PMID:25922678

  7. Susceptibility of bovine dental enamel with initial erosion lesion to new erosive challenges.

    Science.gov (United States)

    Oliveira, Gabriela Cristina de; Tereza, Guida Paola Genovez; Boteon, Ana Paula; Ferrairo, Brunna Mota; Gonçalves, Priscilla Santana Pinto; Silva, Thiago Cruvinel da; Honório, Heitor Marques; Rios, Daniela

    2017-01-01

    This in vitro study evaluated the impact of initial erosion on the susceptibility of enamel to further erosive challenge. Thirty bovine enamel blocks were selected by surface hardness and randomized into two groups (n = 15): GC- group composed by enamel blocks without erosion lesion and GT- group composed by enamel blocks with initial erosion lesion. The baseline profile of each block was determined using the profilometer. The initial erosion was produced by immersing the blocks into HCl 0.01 M, pH 2.3 for 30 seconds, under stirring. The erosive cycling consisted of blocks immersion in hydrochloric acid (0.01 M, pH 2.3) for 2 minutes, followed by immersion in artificial saliva for 120 minutes. This procedure was repeated 4 times a day for 5 days, and the blocks were kept in artificial saliva overnight. After erosive cycling, final profile measurement was performed. Profilometry measured the enamel loss by the superposition of initial and final profiles. Data were analyzed by t-test (perosion on bovine dental enamel does not enhance its susceptibility to new erosive challenges.

  8. Prevalence and risk factors for dental erosion among 11- to 14-year-old school children in South India.

    Science.gov (United States)

    Kumar, Sandeep; Acharya, Shashidhar; Mishra, Prashant; Debnath, Nitai; Vasthare, Ramprasad

    2013-01-01

    This cross-sectional survey was conducted to assess the prevalence and severity of dental erosion and to determine the potential risk factors for dental erosion among 11- to 14-year-old school children in South India. The total sample size for the study was 605, of which 303 school children were from private schools and 302 from public schools. A questionnaire was designed to record information about socio-demographic characteristics, oral hygiene practices, dietary habits and risk factors for dental erosion. Chi square test, bivariate analysis and Logistic regression analysis were performed to analyse the data. The children who consumed lemon several times a day (OR = 13.41, P dental erosion. The overall prevalence of dental erosion was found to be low (8.9%). Erosion was found to be greater in posterior teeth (65.6%) than anterior teeth (34.4%). Loss of enamel only with loss of surface contour was observed in most (94.8%) of the cases. The prevalence of dental erosion was found to be low in school children. Private school children were affected more by dental erosion. Frequency of lemon consumption and consumption of carbonated drinks were identified as risk factors.

  9. [Dental erosion and young adults: what do they know and how would they like to receive information?

    Science.gov (United States)

    Verploegen, V J N; Schuller, A A

    2017-09-01

    Dental erosion occurs often among adolescents and young adults in the Netherlands. This problem requires attention because its consequences are irreversible. In this study (part of the 'Dental Research and Practice in the North Netherlands' project) a questionnaire was distributed to 331 young adults (age 20 to 25) from 25 dental practices. The goal of the study was to find out how much young adults know about dental erosion and how they wish to receive dental information. The results show that much is still unknown about dental erosion among young adults and that the extent of knowledge depended of the level of education and on information on dental erosion that had already been received. Participants preferred to receive information in a conversation with an oral healthcare professional, with the support of printed matter.

  10. Prevalence of dental erosion in adolescent competitive swimmers exposed to gas-chlorinated swimming pool water.

    Science.gov (United States)

    Buczkowska-Radlińska, J; Łagocka, R; Kaczmarek, W; Górski, M; Nowicka, A

    2013-03-01

    The purpose of this study was to analyze the prevalence of dental erosion among competitive swimmers of the local swimming club in Szczecin, Poland, who train in closely monitored gas-chlorinated swimming pool water. The population for this survey consisted of a group of junior competitive swimmers who had been training for an average of 7 years, a group of senior competitive swimmers who had been training for an average of 10 years, and a group of recreational swimmers. All subjects underwent a clinical dental examination and responded to a questionnaire regarding aspects of dental erosion. In pool water samples, the concentration of calcium, magnesium, phosphate, sodium, and potassium ions and pH were determined. The degree of hydroxyapatite saturation was also calculated. Dental erosion was found in more than 26 % of the competitive swimmers and 10 % of the recreational swimmers. The lesions in competitive swimmers were on both the labial and palatal surfaces of the anterior teeth, whereas erosions in recreational swimmers developed exclusively on the palatal surfaces. Although the pH of the pool water was neutral, it was undersaturated with respect to hydroxyapatite. The factors that increase the risk of dental erosion include the duration of swimming and the amount of training. An increased risk of erosion may be related to undersaturation of pool water with hydroxyapatite components. To decrease the risk of erosion in competitive swimmers, the degree of dental hydroxyapatite saturation should be a controlled parameter in pool water.

  11. Dental erosion among 12-year-old schoolchildren: a population-based cross-sectional study in South Brazil.

    Science.gov (United States)

    Alves, Luana Severo; Brusius, Carolina Doege; Damé-Teixeira, Nailê; Maltz, Marisa; Susin, Cristiano

    2015-12-01

    To assess the epidemiology and risk indicators for dental erosion among 12-year-old schoolchildren in South Brazil. A population-based cross-sectional survey was conducted in Porto Alegre, Brazil, using a representative sample of 12-year-old schoolchildren (n = 1,528). Dental erosion was recorded according to the Basic Erosive Wear Examination (BEWE) index. Parents answered questions on socio-economic status, brushing frequency and general health. Schoolchildren answered questions on dietary habits. Anthropometric data were collected. Statistical analysis included logistic and Poisson regression models. The prevalence of dental erosion was 15% [95% confidence interval (95% CI): 13.6-16.5], being mainly mild erosion. Boys [odds ratio (OR) = 1.57, 95% CI: 1.17-2.10], private school attendees (OR = 1.45, 95% CI: 1.01-2.06) and schoolchildren reporting the daily consumption of soft drinks (OR = 5.04, 95% CI: 1.17-21.71) were more likely to have at least one tooth with dental erosion. Gender [boys, rate ratio (RR) = 1.66, 95% CI: 1.28-2.17], type of school (private, RR = 1.89, 95% CI: 1.53-2.35), the consumption of soft drinks (sometimes: RR = 5.27, 95% CI: 1.46-19.05; daily: RR = 6.82, 95% CI: 1.39-33.50) and the daily consumption of lemon (RR = 1.49, 95% CI: 1.11-2.00) were significantly associated with the number of affected surfaces. The present study found a moderate prevalence of dental erosion among young schoolchildren, with mild erosion being the most prevalent condition. Socio demographic variables and dietary habits were associated with dental erosion in this population. © 2015 FDI World Dental Federation.

  12. Methodological considerations concerning the development of oral dental erosion indexes: literature survey, validity and reliability

    Science.gov (United States)

    Kutschmann, Marcus; Bardehle, Doris

    2008-01-01

    Within the context of preventing non-communicable diseases, the World Health Report (2002) and the WHO Global Oral Health Program (2003) put forward a new strategy of disease prevention and health promotion. Greater emphasis is placed on developing global policies in oral health promotion and oral disease prevention. The Decayed, Missing, Filled Teeth (DMFT) index does not meet new challenges in the field of oral health. Dental erosion seems to be a growing problem, and in some countries, an increase in erosion of teeth is associated with an increase in the consumption of beverages containing acids. Therefore, within a revision of the WHO Oral Health Surveys Basic Methods, new oral disease patterns, e.g. dental erosion, have to be taken into account. Within the last 20 years, many studies on dental erosion have been carried out and published. There has been a rapid growth in the number of indexes quantifying dental erosion process in different age groups. However, these indexes are not comparable. This article discusses quality criteria which an index intended for assessing tooth erosion should possess. PMID:18228060

  13. Determination of Prevalence of Dental Erosion in 12 - 14 Years School Children and Its Relationship with Dietary Habits.

    Science.gov (United States)

    Shahbaz, Uzma; Quadir, Fauzia; Hosein, Tasleem

    2016-07-01

    To determine the frequency of dental erosion in 12-14 years school children and its association with dietary habits. Observational cross-sectional analytical study. Fatima Jinnah Dental College, Karachi, from January to June 2010. School children aged between 12 - 14 years were included in this study. Dental erosion was detected by visual examination. Aself-developed questionnaire was used to assess the dietary habits of children. Acidic diet was considered a diet that has an acidic pH. The amount of consumption of acidic drinks and food per week was categorized into low consumption (1 - 7 times / week) and medium consumption (8 - 21 times / week). Chi-square test was applied to see any statistical difference between diet and tooth erosion at 95% CI. The results showed a high frequency of (46%) dental erosion in children, which was significantly higher (p dental erosion in children. Acidic diets need to be controlled in frequency to prevent dental erosion.

  14. The prevalence of dental erosion in Nigerian patients with gastro-oesophageal reflux disease

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    Agbakwuru Elugwaraonu A

    2005-03-01

    Full Text Available Abstract Background In various people of the Western world, gastro-oesophageal reflux (GOR has been reported to be a common problem. Various studies have also assessed the relationship between GOR and dental erosion. The authors are not aware of such studies in Nigerians. It is therefore the aims of the present study to estimate the prevalence of GOR; to estimate the prevalence of dental erosion in patients with GORD; to document the oral findings in patients diagnosed with GORD and to compare these findings with previous studies elsewhere. Methods A total of 225 subjects comprising of 100 volunteers and 125 patients diagnosed with GORD were involved in this study. History of gastric juice regurgitation and heartburn were recorded. Oral examination to quantify loss of tooth structure was done using the tooth wear index (TWI designed by Smith and Knight (1984. Results Twenty patients with GORD presented with dental erosion in the maxillary anterior teeth with TWI scores ranging from 1–3. The prevalence of erosion was found to be statistically significant between GORD patients (16% and control (5% (p 0.05. Conclusion The present study supports the consideration of dental erosion as the extra-oesophageal manifestation of GORD. However the association between GORD and burning mouth sensation needs more investigation.

  15. Polarization sensitive camera for the in vitro diagnostic and monitoring of dental erosion

    Science.gov (United States)

    Bossen, Anke; Rakhmatullina, Ekaterina; Lussi, Adrian; Meier, Christoph

    Due to a frequent consumption of acidic food and beverages, the prevalence of dental erosion increases worldwide. In an initial erosion stage, the hard dental tissue is softened due to acidic demineralization. As erosion progresses, a gradual tissue wear occurs resulting in thinning of the enamel. Complete loss of the enamel tissue can be observed in severe clinical cases. Therefore, it is essential to provide a diagnosis tool for an accurate detection and monitoring of dental erosion already at early stages. In this manuscript, we present the development of a polarization sensitive imaging camera for the visualization and quantification of dental erosion. The system consists of two CMOS cameras mounted on two sides of a polarizing beamsplitter. A horizontal linearly polarized light source is positioned orthogonal to the camera to ensure an incidence illumination and detection angles of 45°. The specular reflected light from the enamel surface is collected with an objective lens mounted on the beam splitter and divided into horizontal (H) and vertical (V) components on each associate camera. Images of non-eroded and eroded enamel surfaces at different erosion degrees were recorded and assessed with diagnostic software. The software was designed to generate and display two types of images: distribution of the reflection intensity (V) and a polarization ratio (H-V)/(H+V) throughout the analyzed tissue area. The measurements and visualization of these two optical parameters, i.e. specular reflection intensity and the polarization ratio, allowed detection and quantification of enamel erosion at early stages in vitro.

  16. Susceptibility of bovine dental enamel with initial erosion lesion to new erosive challenges.

    Directory of Open Access Journals (Sweden)

    Gabriela Cristina de Oliveira

    Full Text Available This in vitro study evaluated the impact of initial erosion on the susceptibility of enamel to further erosive challenge. Thirty bovine enamel blocks were selected by surface hardness and randomized into two groups (n = 15: GC- group composed by enamel blocks without erosion lesion and GT- group composed by enamel blocks with initial erosion lesion. The baseline profile of each block was determined using the profilometer. The initial erosion was produced by immersing the blocks into HCl 0.01 M, pH 2.3 for 30 seconds, under stirring. The erosive cycling consisted of blocks immersion in hydrochloric acid (0.01 M, pH 2.3 for 2 minutes, followed by immersion in artificial saliva for 120 minutes. This procedure was repeated 4 times a day for 5 days, and the blocks were kept in artificial saliva overnight. After erosive cycling, final profile measurement was performed. Profilometry measured the enamel loss by the superposition of initial and final profiles. Data were analyzed by t-test (p<0.05. The result showed no statistically significant difference between groups (GS = 14.60±2.86 and GE = .14.69±2.21 μm. The presence of initial erosion on bovine dental enamel does not enhance its susceptibility to new erosive challenges.

  17. Prevalence and Extrinsic Risk Factors for Dental Erosion in Adolescents.

    Science.gov (United States)

    Mafla, Ana C; Cerón-Bastidas, Ximena A; Munoz-Ceballos, Maria E; Vallejo-Bravo, Diana C; Fajardo-Santacruz, Maria C

    This manuscript examined the prevalence and extrinsic risk factors for dental erosion (DE) in early and middle adolescents in Pasto, Colombia. Dental erosion was evaluated in a random sample of 384 individuals aged 10-15 years attending three primary and high schools in this cross-sectional study. Clinical dental assessment for DE was done using O'Sullivan index. Data on general sociodemographic variables and extrinsic risks factors were obtained. Descriptive and univariate binary logistic regression analyses were performed. Dental erosion was observed in 57.3% of individuals. The univariate binary logistic regression analysis showed that frequency of drinking natural fruit juices (OR 2.670, 95% CI 1.346 - 5.295, P=0.004) and their pH (OR 2.303, 95% CI 1.292 - 4.107, P=0.004) were more associated with the odd of DE in early adolescence. However, a high SES (OR 10.360, 95% CI 3.700 - 29.010, P<0.001) and frequency of snacks with artificial lemon taste (OR 3.659, 95% CI 1.506 - 8.891, P=0.003) were highly associated with the risk of DE in middle adolescence. The results suggest that DE is a prevalent condition in adolescents living in a city in southern Colombia. The transition from early to middle adolescence implies new bio-psychosocial changes, which increase the risk for DE.

  18. Dental erosions and other extra-oesophageal symptoms of gastro-oesophageal reflux disease: Evidence, treatment response and areas of uncertainty.

    Science.gov (United States)

    Pauwels, Ans

    2015-04-01

    Extra-oesophageal symptoms of gastro-oesophageal reflux disease (GORD) are often studied, but remain a subject of debate. It has been clearly shown that there is a relationship between the extra-oesophageal symptoms chronic cough, asthma, laryngitis and dental erosion and GORD. Literature is abundant concerning reflux-related cough and reflux-related asthma, but much less is known about reflux-related dental erosions. The prevalence of dental erosion in GORD and vice versa, the prevalence of GORD in patients with dental erosion is high but the exact mechanism of reflux-induced tooth wear erosion is still under review.

  19. Effect of mouthrinses with different active agents in the prevention of initial dental erosion.

    Science.gov (United States)

    de Oliveira, Tatiane Alexandre; Scaramucci, Tais; Nogueira, Fernando Neves; Simões, Alyne; Sobral, Maria Angela Pita

    2015-01-01

    Hydrochloric acid (HCl) from the gastric juice is the only source of intrinsic acid, which can reach the oral cavity in cases of gastroesophageal reflux or chronic vomiting, enhancing the risk of dental erosion. Compare the effects of mouthrinses with different active agents in the prevention of initial dental erosion caused by HCl. Casein (CAS at 0.2%), sodium hexametaphosphate (HMP at 0.02%), titanium tetrafluoride (TiF4 at 0.34%), and stannous fluoride (SnF2 at 0.87%) were individually added to an experimental mouthrinse. The mouthrinse without additives was used as the negative control (C) and a commercially available mouthrinse for erosion (ELM-Elmex®) as the reference product. Enamel specimens were exposed to human saliva and randomly assigned to 6 experimental groups (n = 8). Specimens were submitted to erosion in HCl for 10 s, followed by to the experimental mouthrinses for 30 s, and artificial saliva for 60 min. This cycle was repeated 3 times. The total amounts of calcium and phosphorus released by the specimens in the 2nd and 3rd erosive challenges were evaluated by atomic emission spectrometry. Statistical analysis used Shapiro-Wilks and Hartley tests, followed by one-way ANOVA and Tukey tests. When compared with C, ELM and HMP presented significantly less calcium in solution, with no difference between them. All the groups showed similar and significantly less phosphorus than C, except CAS. HMP was the only agent that could match the protection against initial erosion of the commercially available mouthrinse in both analyses.

  20. Effect of endurance training on dental erosion, caries, and saliva.

    Science.gov (United States)

    Frese, C; Frese, F; Kuhlmann, S; Saure, D; Reljic, D; Staehle, H J; Wolff, D

    2015-06-01

    The aim of this investigation was to give insights into the impact of endurance training on oral health, with regard to tooth erosion, caries, and salivary parameters. The study included 35 triathletes and 35 non-exercising controls. The clinical investigation comprised oral examination, assessment of oral status with special regard to caries and erosion, saliva testing during inactivity, and a self-administered questionnaire about eating, drinking, and oral hygiene behavior. In addition, athletes were asked about their training habits and intake of beverages and sports nutrition. For saliva assessment during exercise, a subsample of n = 15 athletes volunteered in an incremental running field test (IRFT). Athletes showed an increased risk for dental erosion (P = 0.001). No differences were observed with regard to caries prevalence and salivary parameters measured during inactivity between athletes and controls. Among athletes, a significant correlation was found between caries prevalence and the cumulative weekly training time (r = 0.347, P = 0.04). In athletes after IRFT and at maximum workload, saliva flow rates decreased (P = 0.001 stimulated; P = 0.01 unstimulated) and saliva pH increased significantly (P = 0.003). Higher risk for dental erosions, exercise-dependent caries risk, and load-dependent changes in saliva parameters point out the need for risk-adapted preventive dental concepts in the field of sports dentistry. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Determination of prevalence of dental erosion in 12-14 years school children and its relationship with dietary habits

    International Nuclear Information System (INIS)

    Shahbaz, U.; Hosein, T.; Fauzia, Q.

    2016-01-01

    Objective: To determine the frequency of dental erosion in 12-14 years school children and its association with dietary habits. Study Design: Observational cross-sectional analytical study. Place and Duration of Study: Fatima Jinnah Dental College, Karachi, from January to June 2010. Methodology: School children aged between 12 - 14 years were included in this study. Dental erosion was detected by visual examination. Aself-developed questionnaire was used to assess the dietary habits of children. Acidic diet was considered a diet that has an acidic pH. The amount of consumption of acidic drinks and food per week was categorized into low consumption (1 - 7 times / week) and medium consumption (8 - 21 times / week). Chi-square test was applied to see any statistical difference between diet and tooth erosion at 95 percent CI. Results: The Results showed a high frequency of (46 percent) dental erosion in children, which was significantly higher (p < 0.001) in children with more acidic diet. Conclusion: This study highlights the impact of dietary habits on the prevalence of dental erosion in children. Acidic diets need to be controlled in frequency to prevent dental erosion. (author)

  2. Prevalence and factors associated with dental erosion in individuals aged 12-30 years in a northeastern Brazilian city.

    Science.gov (United States)

    Luciano, Luanda Cristina O; Ferreira, Meire Coelho; Paschoal, Marco Aurelio

    2017-01-01

    Dental erosion in young individuals has increased significantly in recent years, due to changes in lifestyle. Thus, the present study investigated the prevalence and factors associated with dental erosion in individuals aged 12-30 years in the city of Imperatriz of Maranhão, Brazil. A cross-sectional study was conducted on 335 individuals who answered a questionnaire consisting of variables related to dental erosion. Afterwards, the individuals were subjected to clinical examinations and the basic erosive wear examination index was used to classify their teeth according to the presence and severity of dental erosion. Descriptive statistics, the chi-square test, Poisson univariate and multivariate regression were performed at 5% level of significance. The sample was characterized by 204 females (60.9%), the majority of whom were from 12 to 19 years of age (78.5%), among whom 28.7% presented dental erosion. Their monthly family income was from 1 to 3 minimum wages (56.4%). The variables that were significantly associated with the outcome were family income, chewing gum, and consumption of soft-drinks/juices before going to sleep ( p =0.03, p =0.001, and p =0.04, respectively). Individuals who chewed chewing gum were 2.27 times (95% CI =1.43-3.60) more likely to present dental erosion than those who did not chew gum. Individuals who ingested soft drinks or juices were 2.30 times (95% CI =1.30-4.10) more likely to present dental erosion. The prevalence of erosion reflected the need for programs of prevention and guidance for patients about the etiological factors of the disease.

  3. The prevalence of dental erosion and associated risk factors in 12-13-year-old school children in Southern China.

    Science.gov (United States)

    Wang, Ping; Lin, Huan Cai; Chen, Jian Hong; Liang, Huan You

    2010-08-12

    Dental erosion has been investigated in developed and developing countries and the prevalence varies considerably in different countries, geographic locations, and age groups. With the lifestyle of the Chinese people changing significantly over the decades, dental erosion has begun to receive more attention. However, the information about dental erosion in China is scarce. The purpose of this study was to explore the prevalence of dental erosion and associated risk factors in 12-13-year-old school children in Guangzhou, Southern China. This cross-sectional survey was performed by two trained, calibrated examiners. A stratified random sample of 12-13-year-old children (774 boys and 725 girls) from 10 schools was examined for dental erosion using the diagnostic criteria of Eccles and the index of O'Sullivan was applied to record the distribution, severity, and amount of the lesions. Data on the socio-economic status, health behaviours, and general health involved in the etiology of dental erosion were obtained from a self-completed questionnaire. The analyses were performed using SPSS software. At least one tooth surface with signs of erosion was found in 416 children (27.3%). The most frequently affected teeth were the central incisors (upper central incisors, 16.3% and 15.9%; lower central incisors, 17.4% and 14.8%). The most frequently affected surface was the incisal or occlusal edge (43.2%). The loss of enamel contour was present in 54.6% of the tooth surfaces with erosion. Of the affected tooth surfaces, 69.3% had greater than one-half of the tooth surface was affected. The results from logistic regression analysis demonstrated that the children who were female, consumed carbonated drinks once a week or more, and those whose mothers were educated to the primary level tended to have more dental erosion. Dental erosion in 12-13-year-old Chinese school children is becoming a significant problem. A strategy of offering preventive care, including more campaigns

  4. Effect of mouthrinses with different active agents in the prevention of initial dental erosion

    Directory of Open Access Journals (Sweden)

    Tatiane Alexandre de Oliveira

    2015-01-01

    Full Text Available Introduction: Hydrochloric acid (HCl from the gastric juice is the only source of intrinsic acid, which can reach the oral cavity in cases of gastroesophageal reflux or chronic vomiting, enhancing the risk of dental erosion. Aim: Compare the effects of mouthrinses with different active agents in the prevention of initial dental erosion caused by HCl. Subjects and Methods: Casein (CAS at 0.2%, sodium hexametaphosphate (HMP at 0.02%, titanium tetrafluoride (TiF 4 at 0.34%, and stannous fluoride (SnF 2 at 0.87% were individually added to an experimental mouthrinse. The mouthrinse without additives was used as the negative control (C and a commercially available mouthrinse for erosion (ELM - Elmex ® as the reference product. Enamel specimens were exposed to human saliva and randomly assigned to 6 experimental groups (n = 8. Specimens were submitted to erosion in HCl for 10 s, followed by to the experimental mouthrinses for 30 s, and artificial saliva for 60 min. This cycle was repeated 3 times. The total amounts of calcium and phosphorus released by the specimens in the 2 nd and 3 rd erosive challenges were evaluated by atomic emission spectrometry. Statistical analysis used Shapiro-Wilks and Hartley tests, followed by one-way ANOVA and Tukey tests. Results: When compared with C, ELM and HMP presented significantly less calcium in solution, with no difference between them. All the groups showed similar and significantly less phosphorus than C, except CAS. Conclusions: HMP was the only agent that could match the protection against initial erosion of the commercially available mouthrinse in both analyses.

  5. Saliva in relation to dental erosion before and after radiotherapy

    DEFF Research Database (Denmark)

    Jensdottir, Thorbjorg; von Buchwald, Christian; Nauntofte, Birgitte

    2013-01-01

    Abstract Objective. Low saliva flow and abnormal saliva composition are common conditions after radiotherapy for oral cavity and pharyngeal cancer. Both conditions increase the susceptibility to dental caries and erosion, which may be further accelerated by changes in food preferences. The aim...... of this study was to determine changes in saliva flow and susceptibility to erosive challenges in pharyngeal cancer patients before and after radiotherapy to the head and neck. Materials and methods: The erosive potential of sucking acidic candies with and without calcium was determined in nine patients (50...

  6. Development of an inexpensive optical method for studies of dental erosion process in vitro

    Science.gov (United States)

    Nasution, A. M. T.; Noerjanto, B.; Triwanto, L.

    2008-09-01

    Teeth have important roles in digestion of food, supporting the facial-structure, as well as in articulation of speech. Abnormality in teeth structure can be initiated by an erosion process due to diet or beverages consumption that lead to destruction which affect their functionality. Research to study the erosion processes that lead to teeth's abnormality is important in order to be used as a care and prevention purpose. Accurate measurement methods would be necessary as a research tool, in order to be capable for quantifying dental destruction's degree. In this work an inexpensive optical method as tool to study dental erosion process is developed. It is based on extraction the parameters from the 3D dental visual information. The 3D visual image is obtained from reconstruction of multiple lateral projection of 2D images that captured from many angles. Using a simple motor stepper and a pocket digital camera, sequence of multi-projection 2D images of premolar tooth is obtained. This images are then reconstructed to produce a 3D image, which is useful for quantifying related dental erosion parameters. The quantification process is obtained from the shrinkage of dental volume as well as surface properties due to erosion process. Results of quantification is correlated to the ones of dissolved calcium atom which released from the tooth using atomic absorption spectrometry. This proposed method would be useful as visualization tool in many engineering, dentistry, and medical research. It would be useful also for the educational purposes.

  7. Prevalence and severity of dental erosion among jeep battery manufacturing workers at Metagalli, Mysore: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Jyothi Chavan

    2017-01-01

    Full Text Available Introduction: Majority of people employed in various industries are exposed to hazardous environment. Exposure to chemical agents in the workplace can result in adverse effects on workers. This exposure deteriorates the general and oral health of people, working in industries for long hours. Aim: The aim is to assess the prevalence and severity of dental erosion among battery manufacturing factory workers at Metagalli, Mysore, Karnataka, India. Materials and Methods: A total of 175 jeep battery manufacturing factory workers were enrolled and divided into study and comparison groups based on acid exposure. Demographic details of workers were recorded. Severity of dental erosion was calculated using Smith and Knight tooth wear index. The data were analyzed using Statistical Package for the Social Sciences version 17.0 software. Chi-square test was used to compare the categorical variables. Results: The prevalence of dental erosion among the jeep battery manufacturing factory workers was 80%. Majority of the participants in the study group had severe degree of dental erosion (scores of 3 and 4 when compared to the comparison group. Conclusion: Dental erosion was more prevalent among the jeep battery manufacturing factory workers. Study participants were the more affected group with dental erosion when compared to comparison group.

  8. Soft drinks and in vitro dental erosion.

    Science.gov (United States)

    Gravelle, Brent L; Hagen Ii, Ted W; Mayhew, Susan L; Crumpton, Brooks; Sanders, Tyler; Horne, Victoria

    2015-01-01

    The purpose of this investigation was to determine to what extent the in vitro exposure of healthy teeth to various commonly consumed carbonated soft drinks may precipitate dental erosion. Forty-two healthy, extracted, previously unerupted human molars were weighed prior to, during, and after suspension in various sugared and diet or zero-calorie carbonated beverages for 20 days; the specimens were stored at room temperature while being stirred at 275 rpm. The percentage decrease in tooth weight from before to after exposure represented the weight loss due to enamel erosion; values in the experimental groups varied from 3.22% to 44.52% after 20 days' exposure. Data were subjected to analysis of variance and post hoc Scheffe testing at a level of α = 0.05. Nonsugared drinks (diet and zero-calorie) as a whole were more erosive than sugared beverages. A significant positive correlation was found between the amount of titratable acid and percentage of tooth erosion, while a significant negative correlation was revealed between the beverage pH and percentage of tooth erosion. No significant correlations were found between calcium or phosphate ion concentrations and the amount of erosion. It appears that enamel erosion is dependent on not only the beverage flow rate, pH, and amount of titratable acid, but also whether the soft drink is of the diet or zero-calorie variety, which reflects the type of artificial sweetener present.

  9. Dental erosion among 12-14 year old school children in Khartoum: a pilot study.

    Science.gov (United States)

    El Karim, I A; Sanhouri, N M; Hashim, N T; Ziada, H M

    2007-09-01

    To investigate dental erosion among 12-14 year old Sudanese school children and evaluate the associated risk factors. Cross sectional survey in secondary schools in Khartoum city, Sudan. A sample of 157 school children was obtained from both private and public schools. Erosion on the labial and palatal surfaces of maxillary incisors was measured by criterion based on the Smith and Knight Tooth Wear Index. Dietary intake and other related factors were assessed using a questionnaire. The overall erosion prevalence in this group was 66.9%, of which 45.2% was mild and 21.7% was moderate erosion. A strong association was found between erosion and private schooling (higher socioeconomic groups), carbonated drinks, herbal hibiscus drink and traditional acidic food consumption. There was a high prevalence of dental erosion among Sudanese school children which was mild to moderate in severity and was strongly associated with acidic dietary intake

  10. The prevalence of dental erosion and associated risk factors in 12-13-year-old school children in Southern China

    Directory of Open Access Journals (Sweden)

    Wang Ping

    2010-08-01

    Full Text Available Abstract Background Dental erosion has been investigated in developed and developing countries and the prevalence varies considerably in different countries, geographic locations, and age groups. With the lifestyle of the Chinese people changing significantly over the decades, dental erosion has begun to receive more attention. However, the information about dental erosion in China is scarce. The purpose of this study was to explore the prevalence of dental erosion and associated risk factors in 12-13-year-old school children in Guangzhou, Southern China. Methods This cross-sectional survey was performed by two trained, calibrated examiners. A stratified random sample of 12-13-year-old children (774 boys and 725 girls from 10 schools was examined for dental erosion using the diagnostic criteria of Eccles and the index of O'Sullivan was applied to record the distribution, severity, and amount of the lesions. Data on the socio-economic status, health behaviours, and general health involved in the etiology of dental erosion were obtained from a self-completed questionnaire. The analyses were performed using SPSS software. Results At least one tooth surface with signs of erosion was found in 416 children (27.3%. The most frequently affected teeth were the central incisors (upper central incisors, 16.3% and 15.9%; lower central incisors, 17.4% and 14.8%. The most frequently affected surface was the incisal or occlusal edge (43.2%. The loss of enamel contour was present in 54.6% of the tooth surfaces with erosion. Of the affected tooth surfaces, 69.3% had greater than one-half of the tooth surface was affected. The results from logistic regression analysis demonstrated that the children who were female, consumed carbonated drinks once a week or more, and those whose mothers were educated to the primary level tended to have more dental erosion. Conclusions Dental erosion in 12-13-year-old Chinese school children is becoming a significant problem. A

  11. Registration of dental erosive wear on study models and intra-oral photographs.

    Science.gov (United States)

    Hove, L H; Mulic, A; Tveit, A B; Stenhagen, K R; Skaare, A B; Espelid, I

    2013-02-01

    Clinical photographs and study models may provide permanent records of dental erosion and be useful supplements to clinical registration. To assess the reliability and validity of registrations on clinical photographs and study models performed by a group of examiners. Thirty tooth surfaces were selected and assessed clinically, using the visual erosion dental examination system. The chosen surfaces provided the whole range of dental erosions including sound surfaces. The tooth surfaces were photographed and impressions were obtained for preparation of study models. Thirty-three dentists examined and scored the selected surfaces both on photographs and study models. The quality of diagnosis (AUC, area under curve) was slightly higher using photographs as compared to study models. The difference was statistically significant when the validation criterion was erosion, assuming dentine exposure. The inter-method agreement on photographs and study models versus the clinical evaluation were approximately in the same range with a mean κw of 0.48 and 0.43, respectively. When comparing study models with photographs the mean κw was 0.52. The intra-examiner agreement was strong/substantial for both (photographs mean κw = 0.63 and study models mean κw = 0.60). Linear weighted Cohen's kappa (κw) was used to evaluate inter-method and intra-examiner agreement. Receiver operating characteristic and area under the curves were used to express diagnostic quality according to a clinical examination. The results indicated that photographs were as good as study models for recording erosive lesions.

  12. Effects of fluoride and epigallocatechin gallate on soft-drink-induced dental erosion of enamel and root dentin

    Directory of Open Access Journals (Sweden)

    Yin-Lin Wang

    2018-04-01

    Full Text Available Background/Purpose: Fluoride and epigallocatechin gallate (EGCG have been proven to prevent dental caries. The purpose of this study was to evaluate the effects of fluoride and EGCG on soft-drink-induced dental erosion in vitro. Methods: Forty enamel and dentin specimens were prepared from extracted human teeth. The specimens were divided into 4 groups and treated separately with distilled water (as control, 0.5 M sodium fluoride (NF, 400 μM EGCG (EG, and a solution containing 0.5 M NaF and 400 μM EGCG (FG. Cyclic erosive treatment was performed according to the experimental procedures. The specimens were analyzed using laser scanning confocal microscopy, scanning electron microscopy, and a microhardness tester. The data were analyzed using ANOVA and Bonferroni's post hoc test. The significance level was set at 5%. Results: The amount of substance loss was lower in the NF and EG groups than in the control group (p < 0.05. The erosion-caused substance loss was more pronounced in the dentin than in the enamel specimens. Surface microhardness loss was lower in the NF and EG groups than in the control group (p < 0.05. The diameter of the dentinal tubule was wider in the control group than in the NF and EG groups (p < 0.05. No combined effects were observed in the FG group. Conclusion: Both fluoride and EGCG are effective in preventing soft-drink-induced erosion compared with the control group. Fluoride and EGCG may interfere with each other. The mechanisms of the anti-erosive effect need to be explored in the future. Keywords: Dental erosion, Fluoride, Epigallocatechin gallate, Soft drinks, Laser scanning confocal microscopy

  13. Threshold value of enamel mineral solubility and dental erosion after consuming acidic soft drinks

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2011-09-01

    Full Text Available Background: Dental erosion is irreversible and can caused by acidic soft drink consumption. Dental erosion prevention had already been done, but it still has not been satisfying since the consumption of acidic soft drink is still high. There is still no explanation about the threshold value of enamel mineral solubility and the occurance of dental erosion after consuming acidic soft drink. Purpose: This research is aimed to find the threshold value of enamel mineral solubility and dental erosion before and after consuming acidic soft drinks. Methods: Subjects of the research are saliva and enamel of 12 rabbits, which have some criteria such as age > 70 days, body weight > 600 grams, and teeth considered to be healthy. The sample devided equally into 4 groups. Each of those marmooths was given a drink as much as 2.5 cc/consumption (there are 1, 2 and 3× per day by using syringe without injection needle. Salivary minerals then were examined by using atomic absorption spectrophotometric (ASS, while dental erosion was examined using scanning electron microscop (SEM. The data were analyzed by using Paired t-test. Results: It is known that the threshold value of enamel mineral solubility (K, Na, Fe, Mg, Cl, P, Ca, F, C has significant difference (p < 0.05 after being exposed to folic acid. Meanwhile, Fe did not have significant difference (p = 0.090 after being exposed to citric acid. Similarly, C did not have significant difference (p = 0.063 after being exposed to bicarbonate acid. Furthermore, it is also known that the threshold time value of dental erosion are on the 105th day for folic acid, on the 111th day for citric acid, and on the 117th day for bicarbonate acid. Conclusion: Threshold value of enamel mineral solubility before and after consuming soft drinks containing acid is different. Based on the threshold value of dental erosion, it is known that folic acid is the most erosive acid.Latar belakang: Erosi gigi bersifat irreversible

  14. Effect of dental erosion on oral health among employees of battery-manufacturing units in Baddi, Himachal Pradesh, India.

    Science.gov (United States)

    Bansal, Mohit; Singh, Sunint; Bector, Aditi; Dogra, Mrigank

    2018-01-01

    The objective of the study was to obtain data on prevalence and severity of dental erosion among acid industry workers in Baddi (Himachal Pradesh). A cross-sectional study was conducted among 800 battery industry workers. The demographic details were recorded on a prestructured pro forma. Type III examination was done. Dental erosion was recorded based on the index given by Bardsley (simplified scoring criteria for tooth wear index). Appropriate statistical tests were used to interpret the data. The prevalence of dental erosion was found to be 48.6%. Prevalence increased with the duration of employment. Dental erosion was most commonly found in the labial surfaces of maxillary anterior teeth. Erosion is a condition which is multifactorial and becomes more aggravating in the presence of acidic environment. Therefore, the workers working in such conditions should be more careful, and mandatory policies should also be followed by such industries to maintain the overall health of the workers.

  15. Effects of fluoride and epigallocatechin gallate on soft-drink-induced dental erosion of enamel and root dentin.

    Science.gov (United States)

    Wang, Yin-Lin; Chang, Hao-Hueng; Chiang, Yu-Chih; Lu, Yu-Chen; Lin, Chun-Pin

    2018-04-01

    Fluoride and epigallocatechin gallate (EGCG) have been proven to prevent dental caries. The purpose of this study was to evaluate the effects of fluoride and EGCG on soft-drink-induced dental erosion in vitro. Forty enamel and dentin specimens were prepared from extracted human teeth. The specimens were divided into 4 groups and treated separately with distilled water (as control), 0.5 M sodium fluoride (NF), 400 μM EGCG (EG), and a solution containing 0.5 M NaF and 400 μM EGCG (FG). Cyclic erosive treatment was performed according to the experimental procedures. The specimens were analyzed using laser scanning confocal microscopy, scanning electron microscopy, and a microhardness tester. The data were analyzed using ANOVA and Bonferroni's post hoc test. The significance level was set at 5%. The amount of substance loss was lower in the NF and EG groups than in the control group (p erosion-caused substance loss was more pronounced in the dentin than in the enamel specimens. Surface microhardness loss was lower in the NF and EG groups than in the control group (p erosion compared with the control group. Fluoride and EGCG may interfere with each other. The mechanisms of the anti-erosive effect need to be explored in the future. Copyright © 2018. Published by Elsevier B.V.

  16. Enamel erosion caused by the effervescent acid powder in Tiritón ice cream: An in vitro study.

    Directory of Open Access Journals (Sweden)

    Katherine Beltrán

    2014-12-01

    Full Text Available The aim of this study was to visualize the erosive effect on human dental enamel of effervescent acid powder in the Tiritón ice cream (Savory, Nestle, Vevey, Switzerland. The erosive potential of Tiritón ice cream was determined in in vitro conditions by submitting 5 enamel pieces from 3 healthy first molars. The samples were submitted to the mixture of saliva from a girl without cavity incidence and the effervescent powder in the Tiritón ice cream, at 10, 20, 30, 40 and 50 seconds, then the results were measured by scanning electron microscopy (SEM and measurement of pH. All specimens showed pH 3.0. SEM showed increasing degrees of erosion with longer periods of exposure. The Tiritón ice cream generates a much larger acid solution than necessary for the onset of the dissolution of enamel which subsequently causes susceptibility to dental cavities and erosion, higher than reported for other candies. The images obtained by SEM made possible to visualize clearly the erosive effect produced by the effervescent acid powder in periods of exposure of less than a minute.

  17. Scanning Electrochemical Microscopy as a Tool for the Characterization of Dental Erosion

    Directory of Open Access Journals (Sweden)

    Pollyana S. Castro

    2011-01-01

    Full Text Available When the tooth is exposed to acidic environments, an irreversible loss of dental hard tissue occurs in a process called dental erosion. In this work, the scanning electrochemical microscopy (SECM was used to probe the consumption of protons at the vicinity of a tooth surface with a platinum microelectrode fixed at −0.5 (V versus Ag/AgCl/KCl(sat. SECM approach curves were recorded to assess the extent of diffusion in the solution close to the tooth substrate. SECM images clearly demonstrated that the acid erosion process is very fast at solution pH values in the range between 3 and 4.

  18. CHRONIC COUGH AND DENTAL EROSIONS IN A CHILD WITH GASTROESOPHAGEAL REFLUX EVALUATED BY PH-METRY ASSOCIATED WITH MULTICHANNEL INTRALUMINAL IMPEDANCE

    Directory of Open Access Journals (Sweden)

    Felicia GALOŞ

    2013-12-01

    Full Text Available The clinical manifestations of the gastroesophageal reflux disease (GERD are multiple and heterogeneous, differing according to age and individual susceptibility. The relationship between respiratory manifestations and the gastroesophageal reflux (GER in children is a contro‑ versial topic on: proving or refuting either cause or effect, with special stress on the most important symptom – cough. Dental erosions can be GERD-related, especially in the case of infants or of neurologically-impaired children. The case of a 4 year and 8 month-old child with gastroeso‑ phageal reflux, with typical (chronic vomiting and atypi‑ cal (chronic cough, dental erosions digestive manifestations, a diagnosis established by pH-metry asso‑ ciated with multichannel intraluminal impedance, will be discussed in the study.

  19. Micro energy-dispersive X-ray fluoresence mapping of enamel and dental materials after chemical erosion.

    Science.gov (United States)

    Soares, Luís Eduardo Silva; de Oliveira, Rodrigo; Nahórny, Sídnei; Santo, Ana Maria do Espírito; Martin, Airton Abrahão

    2012-10-01

    Energy-dispersive X-ray fluorescence was employed to test the hypothesis that beverage consumption or mouthwash utilization will change the chemical properties of dental materials and enamel mineral content. Bovine enamel samples (n = 45) each received two cavity preparations (n = 90), each pair filled with one of three dental materials (R: nanofilled composite resin; GIC: glass-ionomer cement; RMGIC: resin-modified GIC). Furthermore, they were treated with three different solutions (S: saliva; E: erosion/Pepsi Twist®; or EM: erosion+mouthwash/Colgate Plax®). It was found that mineral loss in enamel was greater in GICE samples than in RE > RMGICE > RMGICEM > REM > GICEM. An increased percentage of Zr was found in REM indicating organic matrix degradation. Dental materials tested (R, GIC, and RMGIC) were not able to protect adjacent enamel from acid erosion by the soft drink tested. The use of mouthwash promoted protection of enamel after erosion by the soft drink. To avoid chemical dissolution by mouthwashes, protection by resin composites with surface sealants is recommended.

  20. Morphological and mineral analysis of dental enamel after erosive challenge in gastric juice and orange juice.

    Science.gov (United States)

    Braga, Sheila Regina Maia; De Faria, Dalva Lúcia Araújo; De Oliveira, Elisabeth; Sobral, Maria Angela Pita

    2011-12-01

    This study evaluated and compared in vitro the morphology and mineral composition of dental enamel after erosive challenge in gastric juice and orange juice. Human enamel specimens were submitted to erosive challenge using gastric juice (from endoscopy exam) (n = 10), and orange juice (commercially-available) (n = 10), as follows: 5 min in 3 mL of demineralization solution, rinse with distilled water, and store in artificial saliva for 3 h. This cycle was repeated four times a day for 14 days. Calcium (Ca) loss after acid exposure was determined by atomic emission spectroscopy. The presence of carbonate (CO) and phosphate (PO) in the specimens was evaluated before and after the erosive challenge by FT-Raman spectroscopy. Data were tested using t-tests (P enamel was observed in scanning electron microscopy (SEM). The mean loss of Ca was: 12.74 ± 3.33 mg/L Ca (gastric juice) and 7.07 ± 1.44 mg/L Ca (orange juice). The analysis by atomic emission spectroscopy showed statistically significant difference between erosive potential of juices (P = 0.0003). FT-Raman spectroscopy found no statistically significant difference in the ratio CO/PO after the erosive challenge. The CO/PO ratios values before and after the challenge were: 0.16/0.17 (gastric juice) (P = 0.37) and 0.18/0.14 (orange juice) (P = 0.16). Qualitative analysis by SEM showed intense alterations of enamel surface. The gastric juice caused more changes in morphology and mineral composition of dental enamel than orange juice. The atomic emission spectroscopy showed to be more suitable to analyze small mineral loss after erosive challenge than FT-Raman. Copyright © 2011 Wiley Periodicals, Inc.

  1. Dental erosion, prevalence and risk factors among a group of adolescents in Stockholm County.

    Science.gov (United States)

    Skalsky Jarkander, M; Grindefjord, M; Carlstedt, K

    2018-02-01

    To investigate the prevalence and risk factors of dental erosion (DE) among a group of adolescents in Stockholm County. This cross sectional cohort study was conducted at three clinics of the Public Dental Service in Stockholm County. Fifteen and 17 year old adolescents (1335) who scheduled their regular dental health examination were asked to participate. After drop-outs a sample of 1071 individuals, 547 males and 524 females were enrolled in the study. Presence of erosive wear was diagnosed (yes/no) on marker teeth by trained dentists/dental hygienists and photographs were taken. The adolescents answered a questionnaire regarding oral symptoms, dietary and behavioural factors. Two calibrated specialist dentists performed evaluation of the photographs for severity of DE using a modified version of the Simplified Erosion Partial Recording System (SEPRS). DE was clinically diagnosed in 28.3% of 15 years old and 34.3% of 17 years old. Severe erosive wear (grade 3 and 4 according to SEPRS) was found in 18.3% of the adolescents based upon the intra-oral photographs. DE was more prevalent and severe among males than females. Clinically diagnosed erosive lesions correlated significantly with soft drink consumption (p < 0.001), the use of juice or sport drinks as a thirst quencher after exercise (p = 0.006) and tooth hypersensitivity when eating and drinking (p = 0.012). Furthermore, self-assessed gastric reflux was a factor strongly associated with DE (p < 0.001). The study indicated that DE was common among adolescents in Stockholm County and associated with both internal and external risk factors.

  2. Caries and dental erosion: are Soroti children and adolescents at risk from increased soft-drink availability in Uganda?

    Science.gov (United States)

    Cheng, Jordan; Campbell, Karen

    2016-12-01

    An initial field study to investigate dental caries and dental erosion in children and adolescents in the community of Soroti, Uganda. A stratified two-stage cluster sample of 84 children (ages 8-10) and adolescents (ages 16-19) were recruited. A survey was undertaken to assess the state of determinants of oral health, oral hygiene practices, and soft-drink and sweetened-tea consumption. Intra-oral photographs were taken and reviewed to measure Decayed, Missing, and Filled Teeth (DMFT) and dental erosion. A significant difference was observed in DMFT between children and adolescents (3.7 ± 2.7 versus 2.1 ± 2.4 p=.02). A trend of lower erosion scores was seen in children compared to adolescents. Greater frequency of sweetened-tea consumption over soft-drinks was noted in both groups. This study did not reveal any relationship between different levels of cariogenic beverage consumption and DMFT or dental erosion in this sample group.

  3. Control of erosive tooth wear: possibilities and rationale

    Directory of Open Access Journals (Sweden)

    Mônica Campos Serra

    2009-06-01

    Full Text Available Dental erosion is a type of wear caused by non bacterial acids or chelation. There is evidence of a significant increase in the prevalence of dental wear in the deciduous and permanent teeth as a consequence of the frequent intake of acidic foods and drinks, or due to gastric acid which may reach the oral cavity following reflux or vomiting episodes. The presence of acids is a prerequisite for dental erosion, but the erosive wear is complex and depends on the interaction of biological, chemical and behavioral factors. Even though erosion may be defined or described as an isolated process, in clinical situations other wear phenomena are expected to occur concomitantly, such as abrasive wear (which occurs, e.g, due to tooth brushing or mastication. In order to control dental loss due to erosive wear it is crucial to take into account its multifactorial nature, which predisposes some individuals to the condition.

  4. Prevention of dental erosion of a sports drink by nano-sized hydroxyapatite in situ study.

    Science.gov (United States)

    Min, Ji Hyun; Kwon, Ho Keun; Kim, Baek Il

    2015-01-01

    To evaluate the inhibitory effects of the sports drink containing nano-sized hydroxyapatite (nano-HA) on dental erosion in situ. The study had a single-blind, two-treatment crossover design. The two treatment groups were a control group (CG; Powerade only) and an experimental group (EG; 0.25% wt/vol nano-HA was added to Powerade). Ten subjects wore removable palatal appliances containing bovine enamel specimens. The appliances were immersed in each drink for 10 mins, 4 times a day for 10 days. The tooth surface microhardness (SMH) was tested, and the erosion depth and the morphology of the tooth surface were observed. The data were analysed by repeated measures anova and t-test. Between the baseline and the 10th day, SMH was decreased by 80% in the specimens of the CG (P erosion depth of 12.70 ± 4.66 μm and an irregular tooth surface were observed on the 10th day in the specimens of the CG. No dental erosions, however, was observed in the specimens of the EG. The sports drink containing 0.25% nano-HA was effective in preventing dental erosion in situ. © 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Effect of beverages on bovine dental enamel subjected to erosive challenge with hydrochloric acid.

    Science.gov (United States)

    Amoras, Dinah Ribeiro; Corona, Silmara Aparecida Milori; Rodrigues, Antonio Luiz; Serra, Mônica Campos

    2012-01-01

    This study evaluated by an in vitro model the effect of beverages on dental enamel previously subjected to erosive challenge with hydrochloric acid. The factor under study was the type of beverage, in five levels: Sprite® Zero Low-calorie Soda Lime (positive control), Parmalat® ultra high temperature (UHT) milk, Ades® Original soymilk, Leão® Ice Tea Zero ready-to-drink low-calorie peach-flavored black teaand Prata® natural mineral water (negative control). Seventy-five bovine enamel specimens were distributed among the five types of beverages (n=15), according to a randomized complete block design. For the formation of erosive wear lesions, the specimens were immersed in 10 mL aqueous solution of hydrochloric acid 0.01 M for 2 min. Subsequently, the specimens were immersed in 20 mL of the beverages for 1 min, twice daily for 2 days at room temperature. In between, the specimens were kept in 20 mL of artificial saliva at 37ºC. The response variable was the quantitative enamel microhardness. ANOVA and Tukey's test showed highly significant differences (penamel exposed to hydrochloric acid and beverages. The soft drink caused a significantly higher decrease in microhardness compared with the other beverages. The black tea caused a significantly higher reduction in microhardness than the mineral water, UHT milk and soymilk, but lower than the soft drink. Among the analyzed beverages, the soft drink and the black tea caused the most deleterious effects on dental enamel microhardness.

  6. Occurrence of risk factors for dental erosion in the population of young adults in Norway.

    Science.gov (United States)

    Asmyhr, Øyvind; Grytten, Jostein; Holst, Dorthe

    2012-10-01

    The aim of this study was to describe the occurrence of risk factors for dental erosion for a group of young adults who are particularly susceptible to erosion. Another aim was to describe the awareness of erosion and distribution of risk factors according to the educational background of the parents. The sample (n = 2004 individuals) was randomly drawn from the population of 19-20-year-old Norwegians. The data were collected using telephone interviews. We measured awareness about erosion using the following question: 'Have you ever heard about dental erosion?' We obtained information about the frequency of intake of the following risk factors: soft drinks with and without sugar, and juice. Soft drinks with sugar included lemonade (Coca-Cola, Solo, Pepsi, Mozell and ice tea) and sport drinks (XL1, Maxim). Soft drinks without sugar included Cola light, Zero, PepsiMax, Solo light and ice tea light. Juice included orange, grapefruit, apple and kiwi juice. The parents' level of education was based on the Norwegian school system, which has three levels: compulsory schooling (10 years), upper secondary school education (up to 13 years) and university/college education. The data were analysed using logistic regressions analyses. Awareness of erosion was high - 93.5% of respondents were aware of the problem. The majority of respondents believed that erosion can be prevented - altogether 84.9%. They also believed that soft drinks with and without sugar are equally important for the development of erosion. 17.5% of respondents drank soft drinks with sugar daily or several times a day. The corresponding figures for soft drinks without sugar and juice were 4.9% and 34.1%, respectively. Young adults with mothers with high education drank soft drinks both with and without sugar less frequently than those who had mothers with low education. This pattern was the opposite for juice. Consumption of soft drinks and juice is high, even though awareness and knowledge about the causes

  7. Saliva with reduced calcium and phosphorous concentrations: Effect on erosion dental lesions.

    Science.gov (United States)

    Denucci, Giovanna Corrêa; Mantilla, Taís Fonseca; Amaral, Flávia Lucisano Botelho; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes; Turssi, Cecilia Pedroso

    2018-02-08

    To investigate whether saliva formulations with reduced calcium (Ca) and inorganic phosphorous (Pi) concentration would affect dental erosion caused by hydrochloric acid (HCl). Enamel and root dentine bovine slabs were embedded, polished and measured for surface Knoop microhardness (SMH). After reference areas were created, specimens were exposed to HCl solution (0.01M; pH 2; 120s) and immersed in artificial salivas (6h) containing three different Ca/Pi concentrations (n=15), which simulate serum conditions of normo-, mild- or severe hypocalcaemia. The control group was immersed in Ca/Pi-free saliva. The study protocol was carried out 2x/day for 5 days. Surface loss of enamel and root dentine was assessed using an optical profilometer and SMH was remeasured for enamel. ANOVA (pdental substrate, salivary formulations resembling serum hypocalcaemia affected surface loss due to erosion and rehardening thereof. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Dental erosion in archaeological human remains: A critical review of literature and proposal of a differential diagnosis protocol.

    Science.gov (United States)

    Coupal, Isabelle; Sołtysiak, Arkadiusz

    2017-12-01

    Although studies of dental wear on archaeological human remains have largely focused on mechanical wear (attrition and abrasion) in the past, chemical wear (erosion) is being increasingly identified as a separate form of wear. This paper aims to review the current state of research and to develop a protocol that may be universally used by biorchaeologists to specifically identify dental erosion. A critical review of literature has been done in order to highlight the issues related to diagnosis of dental erosion in archaeological human remains. The bodies of work based on the analysis of both modern and archaeological dentitions raise their separate problems. In addition to a need to re-evaluate symptoms of dental erosion, notably dentin 'cupping', it is apparent that no specific protocol is adapted from medical to archaeological sciences. Authors rather rely on tooth wear indices and photographs of modern clinical cases for diagnosis. Furthermore, the diagenetic chemical alternation has rarely been considered as a bias. Here we suggest a three-step protocol: the primary method is the microscopic identification of dental erosion by SEM, followed by the exclusion of taphonomic aetiology on surrounding bone and soil pH analysis. Archaeologists should also explore possible causative agents of wear using archaeological and historic knowledge about the population being analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Risk behaviors related to eating disorders in adolescents and its association with dental erosion

    Directory of Open Access Journals (Sweden)

    Daniella Fagundes SOUTO

    Full Text Available Abstract Introduction The overvaluation of thinness as a standard of beauty has contributed to the development of eating disorders and has mainly affected adolescents and young adults. Objective To evaluate the prevalence of risk behaviors for eating disorders and their association with dental erosion in adolescents. Material and method This is a cross-sectional observational epidemiological study. The sample consisted of 278 adolescents aged 12 to 19 years, enrolled in a State School in Campinas - SP. Two questionnaires were used for the data collection on eating disorders: Bulimic Investigatory Test of Edinburgh and Eating Attitudes Test -26. The presence of erosion was evaluated by calibrated examiners. Result The mean age of the sample was 14.8 years. The prevalence of mean risk for bulimia in the sample was 43.2% (95% CI: 37.3%-49.0% and the prevalence of adolescents with a probability of developing bulimia was 53.2% (95% CI: 47.4%-59.1%. Of the total, 11.9% (95% CI: 8.1%-15.7% showed results suggestive of anorexia. Among women, 66.9% were classified as probability developing bulimia, whereas in men the prevalence was 39.0%. As for dental erosion, only 1.1% of the sample presented erosion. Conclusion The study pointed to large number of adolescents with risk behaviors for eating disorders but no association was found with dental erosion due to low prevalence.

  10. Analysis of dental erosion induced by different beverages and validity of equipment for identifying early dental erosion, in vitro study.

    Science.gov (United States)

    Jameel, Rafey Ahmad; Khan, Shah Salman; Abdul Rahim, Zubaidah Hj; Bakri, Marina Mohd; Siddiqui, Saima

    2016-07-01

    To understand early dental erosion induced by different beverages and the equipment for its detection. The study was conducted at the University Malaya Medical Centre, Kuala Lumpur, Malaysia, from June to September 2014, and comprised single-rooted, unpolished teeth divided into six groups. Electron micrographs and other baseline readings for further analyses were taken before and after the exposure to different beverages. The teeth were exposed to the beverages using a modified Nordini's artificial mouth model. The positioning of the teeth on the motorised stage of the equipment was standardised. Of the several beverages used, CocaCola had the lowest pH value of 2.53, while tap water had the highest pH of 5.4. Deionised distilled water, which was used as a reference, had a pH near to neutral /alkaline of 7.3. The fluoride content ranged between 9.38ppm in tea and 0.005ppm in orange juice. Teeth exposed to beverages with low pH and considerably high fluoride underwent slight remineralisation (roughness increase 8% from tea), while beverages with no fluoride content and low pH roughened the enamel surface (Coca Cola roughened upto 37%). Quantitative analyses of tooth erosion, micro-hardness, surface-roughness, and surface-height showed that all beverages exhibited positive erosive effect on the tooth enamel surface (pCocaCola was found to be the most erosive agent among both hot and cold beverages (37%), while coffee was more erosive among the hot beverages (29%).

  11. The influence of frequently consumed beverages and snacks on dental erosion among preschool children in Saudi Arabia.

    Science.gov (United States)

    Al-Dlaigan, Yousef H; Al-Meedania, Laila A; Anil, Sukumaran

    2017-12-11

    To determine the prevalence of dental erosion and its association to commonly used beverages and snacks among 3 to 5 year old preschool children in Riyadh, Saudi Arabia. Three hundred eighty-eight preschool children between 3 and 5 years old were selected from 10 different schools using a cluster random sample selection; there were 184 (47%) boys and 204 (53%) girls. The surfaces of each tooth were examined for erosion, and the level of tooth wear was recorded. Data on the frequently used beverages and snacks were obtained by questionnaires completed by the parents of the preschool children. Among the 388 children examined, 47% exhibited low erosion, 10% exhibited moderate erosion and 4% exhibited severe erosion. There was no statistically significant difference between boys and girls in terms of the prevalence of erosion. Sixty percent of the children regularly consumed juice drinks. Among daily consumers, 84% of children showed erosion prevalence with strongly significant association (p erosion (p dental erosion and the frequency of citrus and carbonated juice consumed by the preschool children in Saudi Arabia.

  12. Monitoring dental erosion by colour measurement : An in vitro study

    NARCIS (Netherlands)

    Krikken, J. B.; Zijp, J. R.; Huysmans, M. C. D. N. J. M.

    Objectives: The aim of this study was to develop a method to monitor dental erosion by evaluation of the colour change of teeth as a function of enamel loss, and to evaluate the reproducibility of the method used. Methods: Light reflectance spectra of 12 extracted human incisors were measured using

  13. Dental erosion in patients seeking treatment for gastrointestinal complaints: a case series.

    Science.gov (United States)

    Bruno, Vincenzo; Amato, Massimo; Catapano, Santo; Iovino, Paola

    2015-10-30

    Eating disorders which embrace anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified can be life-threatening due to general medical complications; however, the diagnosis of eating disorder is often delayed due to a low suspicion index. Gastroenterologists are health care providers who may come into contact with patients with undiagnosed eating disorders; it has been previously demonstrated that patients with eating disorders frequently have a significant association with functional dyspepsia. Signs of dental erosion have been described in patients with eating disorders; hence, they may help to identify eating disorders in patients who present with functional dyspepsia and deny having an eating disorder. In this report we describe three cases (a 25-year-old white woman, a 24-year-old white woman, and a 40-year-old white man) with undiagnosed eating disorders, in which a more comprehensive approach, such as the recognition of dental erosion joined with a careful gastrointestinal investigation, was performed to reach a final diagnosis of an eating disorder. The screening for dental erosion in patients seeking or receiving medical treatment for dyspeptic symptoms in a gastrointestinal out-patient clinic could be an aid for gastroenterologists to recognize the presence of an underlying eating disorder. A close collaboration with dentists, in addition to psychiatrists, could provide a more favorable treatment outcome.

  14. Oral regurgitation after reflux provoking meals: a possible cause of dental erosion?

    Science.gov (United States)

    Bartlett, D W; Evans, D F; Smith, B G

    1997-02-01

    Certain foods and drinks such as alcohol, heavily spiced or fatty meals are known to provoke gastro-oesophageal reflux (GOR). This may give rise to symptoms of heartburn, epigastric pain and occasionally oral regurgitation of the gastric contents. Oral regurgitation of gastric juice is important in dentistry because of its association with dental erosion. This study measured oesophageal and oral reflux in 12 healthy subjects after a curry meal taken with alcohol 2 h before sleep. Each subject repeated the test with a bland non-reflux provoking control meal. GOR was measured by recording distal and proximal oesophageal pH on a dual channel, portable pH monitor. Oral pH was measured with a pH sensitive radio-telemetry capsule (RTC) held on the palate in a vacuum formed splint. Signals from the RTC were received by an aerial worn around the head. The pH change produced by GOR was estimated as the percentage time that pH (PTpH) was less than 4 in the distal oesophagus. Similarly, the PTpH was estimated reflux in only two subjects. In one of these subjects the bland meal provoked oral regurgitation with a PTpH < 5.5 of 13.5%. In the remaining subjects little oral regurgitation occurred.

  15. Effects of enamel abrasion, salivary pellicle, and measurement angle on the optical assessment of dental erosion

    Science.gov (United States)

    Lussi, Adrian; Bossen, Anke; Höschele, Christoph; Beyeler, Barbara; Megert, Brigitte; Meier, Christoph; Rakhmatullina, Ekaterina

    2012-09-01

    The present study assessed the effects of abrasion, salivary proteins, and measurement angle on the quantification of early dental erosion by the analysis of reflection intensities from enamel. Enamel from 184 caries-free human molars was used for in vitro erosion in citric acid (pH 3.6). Abrasion of the eroded enamel resulted in a 6% to 14% increase in the specular reflection intensity compared to only eroded enamel, and the reflection increase depended on the erosion degree. Nevertheless, monitoring of early erosion by reflection analysis was possible even in the abraded eroded teeth. The presence of the salivary pellicle induced up to 22% higher reflection intensities due to the smoothing of the eroded enamel by the adhered proteins. However, this measurement artifact could be significantly minimized (pmeasurement angles from 45 to 60 deg did not improve the sensitivity of the analysis at late erosion stages. The applicability of the method for monitoring the remineralization of eroded enamel remained unclear in a demineralization/remineralization cycling model of early dental erosion in vitro.

  16. Saliva composition in three selected groups with normal stimulated salivary flow rates, but yet major differences in caries experience and dental erosion.

    Science.gov (United States)

    Bardow, Allan; Lykkeaa, Joan; Qvist, Vibeke; Ekstrand, Kim; Twetman, Svante; Fiehn, Niels-Erik

    2014-08-01

    It was hypothesized that, by comparing matched subjects with major differences in these dental diseases, but yet normal saliva flow rates, it would be possible to obtain data on the effect of saliva composition on dental disease isolated from the effect of the flow rate. Thus, the aim of the study was to compare the major physicochemical characteristics of stimulated whole saliva in three groups of 85 subjects, each with normal saliva flow rates and at least 24 remaining teeth. A group with very little dental disease (healthy), a group with dental erosion (erosion) and a group with very high caries experience (caries) were chosen. Furthermore, the aim was to determine whether differences among groups could also be found on an individual level. Although it was not possible to retrieve three groups whose members were completely identical, the present study points in the direction that, on a group level, subjects with very little dental disease seemed to have a more favorable physicochemical saliva composition with respect to higher calcium, phosphate, bicarbonate, pH, degree of saturation with respect to hydroxyapatite and a lower critical pH (p dental erosion (p dental caries and erosion in single individuals.

  17. Early diagnosis of teeth erosion using polarized laser speckle imaging

    Science.gov (United States)

    Nader, Christelle Abou; Pellen, Fabrice; Loutfi, Hadi; Mansour, Rassoul; Jeune, Bernard Le; Brun, Guy Le; Abboud, Marie

    2016-07-01

    Dental erosion starts with a chemical attack on dental tissue causing tooth demineralization, altering the tooth structure and making it more sensitive to mechanical erosion. Medical diagnosis of dental erosion is commonly achieved through a visual inspection by the dentist during dental checkups and is therefore highly dependent on the operator's experience. The detection of this disease at preliminary stages is important since, once the damage is done, cares become more complicated. We investigate the difference in light-scattering properties between healthy and eroded teeth. A change in light-scattering properties is observed and a transition from volume to surface backscattering is detected by means of polarized laser speckle imaging as teeth undergo acid etching, suggesting an increase in enamel surface roughness.

  18. A 4 year prospective longitudinal study of progression of dental erosion associated to lifestyle in 13-14 year-old Swedish adolescents.

    Science.gov (United States)

    Hasselkvist, Agneta; Johansson, Anders; Johansson, Ann-Katrin

    2016-04-01

    To evaluate the progression of dental erosion in 13-14 year-olds after 4 years, and its association with lifestyle and oral health. 227 randomly selected 13-14 year-olds from a Public Dental Clinic, Örebro, Sweden, were investigated. A clinical examination was performed which included dental caries/gingival/plaque status, as well as grading of dental erosion at the tooth surface and participant levels in "marker teeth", including buccal/palatal surfaces of 6 maxillary anterior teeth (13-23), and occlusal surfaces of first molars. An interview and a questionnaire regarding drinking habits and other lifestyle factors were completed. All investigations were repeated at follow-up. The participants were divided into high and low progression erosion groups and logistic regression statistics were applied. 175 individuals participated at follow-up. Progression occurred in 35% of the 2566 tooth surfaces. 32% of the surfaces had deteriorated by one severity grade (n=51 individuals) and 3% by two grades (n=2 individuals). Boys showed more severe erosion than girls at the follow-up. Among the variables predicting greater progression, a lower severity of erosive wear at baseline had the highest OR (13.3), followed in descending order by a "retaining" drinking technique, more frequent intake of drinks between meals, low GBI and lesser sour milk intake, with reference to the baseline recording. Using these five variables, sensitivity and specificity were 87% and 67% respectively, for predicting progression of erosion. Progression of erosive lesions in Swedish adolescents aged 13-14 years followed up to age 17-18 years was common and related to certain lifestyle factors. In permanent teeth, dental erosion may develop early in life and its progression is common. Dental health workers should be made aware of this fact and regular screenings for erosion and recording of associated lifestyle factors should be performed. Copyright © 2016 Z. Published by Elsevier Ltd.. All rights

  19. Dental erosion, an extraesophageal manifestation of gastroesophageal reflux disease. The experience of a center for digestive physiology in Southeastern Mexico.

    Science.gov (United States)

    Roesch-Ramos, Laura; Roesch-Dietlen, Federico; Remes-Troche, José María; Romero-Sierra, Graciela; Mata-Tovar, Carlos de Jesús; Azamar-Jácome, Amyra Ali; Barranca-Enríquez, Antonia

    2014-02-01

    Dental erosion (DE) is the loss of the hard tissues of the tooth produced by the action of gastric juice, pepsin and acid on the dental enamel, its frequency ranges from 5 to 53.41 %. In Mexico there are no reports on the frequency and possible association. To establish the prevalence of dental erosion and its relationship to GERD. Prospective, observational, descriptive and comparative study was conducted in 60 patients diagnosed with GERD and 60 healthy patients at the Institute of Medical and Biological Research of the Universidad Veracruzana in Veracruz city. Anthropometric characteristics, dietary habits, oral hygiene, alcohol consumption, smoking, ED index and Index of decayed/missing dental pieces/sealed and correlation between severity of ED and GERD were analyzed. 78.67 % of patients with GERD had ED, 23.33 % corresponded to grade 0, 41.67 % to N1, N2 and 23.33 % to 11.67 % to N3. Predominance of females (2,3:1). The mean age was 50.92 +/- 13.52 years. The severity of dental erosion was significantly related to the severity of reflux, halitosis, CPO index and poor eating habits. There was no statistically significant difference in the other variables analyzed. Dental erosion has a high frequency in patients with GERD and reflux characteristics are directly related to their severity and therefore should be considered as a manifestation of GERD extraesophageal.

  20. [Prevalence of caries and dental erosion among school children in The Hague from 1996-2005

    NARCIS (Netherlands)

    Truin, G.J.; Frencken, J.E.F.M.; Mulder, J.; Kootwijk, A.J.; Jong, E. de

    2007-01-01

    In 2005 a dental survey of the prevalence of caries among 6- and 12-year-old schoolchildren in The Hague was carried out. In the case of the 12-year-olds, the prevalence of dental erosion was also studied. The sample consisted of 814 students in twelve primary schools in The Hague. The results

  1. A New Sugarcane Cystatin Strongly Binds to Dental Enamel and Reduces Erosion.

    Science.gov (United States)

    Santiago, A C; Khan, Z N; Miguel, M C; Gironda, C C; Soares-Costa, A; Pelá, V T; Leite, A L; Edwardson, J M; Buzalaf, M A R; Henrique-Silva, F

    2017-08-01

    Cystatin B was recently identified as an acid-resistant protein in acquired enamel pellicle; it could therefore be included in oral products to protect against caries and erosion. However, human recombinant cystatin is very expensive, and alternatives to its use are necessary. Phytocystatins are reversible inhibitors of cysteine peptidases that are found naturally in plants. In plants, they have several biological and physiological functions, such as the regulation of endogenous processes, defense against pathogens, and response to abiotic stress. Previous studies performed by our research group have reported high inhibitory activity and potential agricultural and medical applications of several sugarcane cystatins, including CaneCPI-1, CaneCPI-2, CaneCPI-3, and CaneCPI-4. In the present study, we report the characterization of a novel sugarcane cystatin, named CaneCPI-5. This cystatin was efficiently expressed in Escherichia coli, and inhibitory assays demonstrated that it was a potent inhibitor of human cathepsins B, K, and L ( K i = 6.87, 0.49, and 0.34 nM, respectively). The ability of CaneCPI-5 to bind to dental enamel was evaluated using atomic force microscopy. Its capacity to protect against initial enamel erosion was also tested in vitro via changes in surface hardness. CaneCPI-5 showed a very large force of interaction with enamel (e.g., compared with mucin and casein) and significantly reduced initial enamel erosion. These results suggest that the inclusion of CaneCPIs in dental products might confer protection against enamel erosion.

  2. Simplified treatment of severe dental erosion with ultrathin CAD-CAM composite occlusal veneers and anterior bilaminar veneers.

    Science.gov (United States)

    Schlichting, Luís Henrique; Resende, Tayane Holz; Reis, Kátia Rodrigues; Magne, Pascal

    2016-10-01

    Restorative treatment for patients with dental erosion requires an analysis of the degree of structural damage. Patients affected by moderate to severe dental erosion are particularly challenging because complex occlusal reconstruction will be needed. Ultrathin bonded occlusal veneers represent a conservative alternative to traditional onlays and complete coverage crowns for the treatment of severe erosion. This article describes a complete mouth rehabilitation with ultrathin computer-aided design and computer-aided manufacturing (CAD-CAM) composite resin occlusal veneers in a patient with a severely eroded dentition. In the maxillary anterior teeth, the bilaminar approach was chosen with lingual composite resin veneers and labial porcelain veneers. The main benefit of this approach is the possibility of using additive adhesive techniques, allowing only strategic reduction of sound dental structure or no preparation. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  3. Dental erosion, an extraesophageal manifestation of gastroesophageal reflux disease: the experience of a center for digestive physiology in Southeastern Mexico

    Directory of Open Access Journals (Sweden)

    Laura Roesch-Ramos

    2014-02-01

    Full Text Available Background: Dental erosion (DE is the loss of the hard tissues of the tooth produced by the action of gastric juice, pepsin and acid on the dental enamel, its frequency ranges from 5to 53.41%. In Mexico there are no reports on the frequency and possible association. Objective: To establish the prevalence of dental erosion and its relationship to GERD. Patients and methods: Prospective, observational, descriptive and comparative study was conducted in 60patients diagnosed with GERD and 60healthy patients at the Institute of Medical and Biological Research of the Universidad Veracruzana in Veracruz city. Anthropometric characteristics, dietary habits, oral hygiene, alcohol consumption, smoking, ED index and Index of decayed/missing dental pieces/sealed and correlation between severity of ED and GERD were analyzed. Results: 78.67% of patients with GERD had ED, 23.33% corresponded to grade 0, 41.67% to N1, N2and 23.33% to 11.67% to N3. Predominance of females (2.3:1. The mean age was 50.92± 13.52years. The severity of dental erosion was significantly related to the severity of reflux, halitosis, CPO index and poor eating habits. There was no statistically significant difference in the other variables analyzed. Conclusions: Dental erosion has a high frequency in patients with GERD and reflux characteristics are directly related to their severity and therefore should be considered as a manifestation of GERD extraesophageal.

  4. Dental Erosion in Patients with Gastroesophageal Reflux Disease (GERD) in a Sample of Patients Referred to the Motahari Clinic, Shiraz, Iran.

    Science.gov (United States)

    Alavi, G; Alavi, Aa; Saberfiroozi, M; Sarbazi, Ah; Motamedi, M; Hamedani, Sh

    2014-03-01

    Systematic reviews of the literature show that the dental erosion is associated with the gastroesophageal reflux disease (GERD).The prevalence of the problem may not be exclusively similar in different countries. The purpose of this study was to investigate the association of gastro-esophageal reflux disease (GERD) with dental erosion in a sample of Iranian population regarding the standing difference in the Iranian oral hygiene and diet. Material s and Method: 140 patients with the average age of 30 to 50 years old comprised the study group. The participants were already eligible for the endoscopic examination, diagnosed by their gastroenterologist. All patients completed a detailed questionnaire regarding the medical and dental situations. After completing the questionnaire and before endoscopy, dental examination was performed by two blinded dentists.The endoscopy was then performed by a gastroenterologist and the patients were divided into three groups of healthy, suspected to GERD, and positive GERD. Data were collected and analyzed by Chi- Square test. The cross tabulation test was performed to compare the qualitative variants and discover the correlations. The statistical significance was adopted as: p dental erosion in GERD patients (22.6%) was found to be higher than the suspected (5.3%) and the healthy (7%) individuals. This study declared the GERD patients are at higher risk of developing dental erosion compared to the healthy individuals in a sample of Iranian population.

  5. Dental erosion and severe tooth decay related to soft drinks: a case report and literature review.

    Science.gov (United States)

    Cheng, Ran; Yang, Hui; Shao, Mei-ying; Hu, Tao; Zhou, Xue-dong

    2009-05-01

    Soft drinks have many potential health problems. The inherent acids and sugars have both acidogenic and cariogenic potential, resulting in dental caries and potential enamel erosion. In this report we present a 25-year-old man complaining with the severe worn-out of the front teeth during the past 3 years. He had a history of drinking cola for more than 7 years and had a poor oral hygiene. Severe decays were present in the incisors and the canines, while less severe lesions were noted on the premolars and the molars. The review is to show the relationship between dental erosion and caries and soft drinks. Some efforts have been taken to reduce the harmful effect of soft drinks.

  6. Dental erosion and severe tooth decay related to soft drinks: a case report and literature review*

    Science.gov (United States)

    Cheng, Ran; Yang, Hui; Shao, Mei-ying; Hu, Tao; Zhou, Xue-dong

    2009-01-01

    Soft drinks have many potential health problems. The inherent acids and sugars have both acidogenic and cariogenic potential, resulting in dental caries and potential enamel erosion. In this report we present a 25-year-old man complaining with the severe worn-out of the front teeth during the past 3 years. He had a history of drinking cola for more than 7 years and had a poor oral hygiene. Severe decays were present in the incisors and the canines, while less severe lesions were noted on the premolars and the molars. The review is to show the relationship between dental erosion and caries and soft drinks. Some efforts have been taken to reduce the harmful effect of soft drinks. PMID:19434767

  7. Rumination Syndrome and Dental Erosions in Children.

    Science.gov (United States)

    Monagas, Javier; Ritwik, Priyanshi; Kolomensky, Andrew; Acosta, Julio; Kay, Danielle; Clendaniel, Lindsey; Hyman, Paul E

    2017-06-01

    Rumination syndrome is the effortless regurgitation of recently ingested food with subsequent reswallowing or spitting out. Dental erosion (DE) affects 2% to 5% of the population. DE is defined as loss of tooth structure by a chemical process that does not involve bacteria. Our objective was to compare the frequency of DE among children with rumination syndrome with healthy controls. We enrolled 30 patients 4 to 21 years of age diagnosed with rumination syndrome, and 30 age- and sex-matched healthy control subjects. Patients were evaluated by pediatric dentists for presence of DE with Taji et al a validated grading system. Patients with rumination were more likely to have DE (P syndrome, 23 (77%) had DE, compared with 4 (13%) control subjects. DEs are more frequent in patients with rumination syndrome.

  8. Dental root periapical resorption caused by orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Pinandi Sri Pudyani

    2006-03-01

    Full Text Available Dental root resorption especially in maxillary incisive region almost always happens simultaneously with orthodontic treatment, and it gained researchers attention, in particular after the use of periapical radiography. However, the fundamental etiology of dental root resorption is still dubious. Multifactoral causes are mentioned, among others are hormonal, nutritition, trauma, dental root form and dental root structure anomalies, genetic, while from treatment side are duration, types, strength scale and dental movement types. Based on these findings, orthodontic treatment was proven to cause dental root resorption in maxillary incisive teeth.

  9. Local mucous membrane lesions caused by irradiation of the oropharynx can be prevented by a dental shield

    International Nuclear Information System (INIS)

    Schratter-Sehn, A.U.; Vienna Univ.; Schmidt, W.F.O.; Kaercher, K.H.; Kielhauser, R.; Langer, H.

    1992-01-01

    In patients with metallic dental fillings radiation therapy to the oral cavity can cause mucous membrane lesions, which are more severe than expected. They appear as circumscribed erosions, opposite to metallic fillings and are caused by an increase in radiation dose through secondary radiation due to the higher density and atomic number of the filling material. This dose increase can be directly measured with 0.1 mm thin sheets of graphite-loaded TLD's (LiF, Vinten). For Co-60 gamma rays a commercial amalgam filling caused a dose increase by a factor of 1.7. The half value layer for this additional radiation was measured to be approximately 0.4 mm tissue. In order to avoid painful mucous membrane ulcerations which are even more a problem if hyperfractionated treatment schedules are used, we constructed individual dental shields for each patient. As shielding material we used a dental impression material (Optosil P + , Bayer). This method was tested in 35 patients, in all of them circumscribed mucous membrane ulcerations could be avoided. The method proved to be fast and simple and was very well tolerated by all patients. (orig.) [de

  10. Acids with an equivalent taste lead to different erosion of human dental enamel.

    Science.gov (United States)

    Beyer, Markus; Reichert, Jörg; Bossert, Jörg; Sigusch, Bernd W; Watts, David C; Jandt, Klaus D

    2011-10-01

    The consumption of acidic soft drinks may lead to demineralization and softening of human dental enamel, known as dental erosion. The aims of this in vitro study were to determine: (i) if different acids with a similar sensorial acidic taste lead to different hardness loss of enamel and (ii) if the fruit acids tartaric, malic, lactic or ascorbic acid lead to less hardness loss of enamel than citric or phosphoric acid when their concentration in solution is based on an equivalent sensorial acidic taste. Enamel samples of non-erupted human third molars were treated with acidic solutions of tartaric (TA), malic (MA), lactic (LA), ascorbic (AA), phosphoric (PA) and citric (CA) acids with a concentration that gave an equivalent sensorial acidic taste. The acidic solutions were characterized by pH value and titratable acidity. Atomic force microscopy (AFM) based nanoindentation was used to study the nano mechanical properties and scanning electron microscopy (SEM) was used to study the morphology of the treated enamel samples and the untreated control areas, respectively. The investigated acids fell into two groups. The nano hardnesses of MA, TA and CA treated enamel samples (group I) were statistically significantly greater (penamel samples (group II). Within each group the nano hardness was not statistically significantly different (p>0.05). The SEM micrographs showed different etch prism morphologies depending on the acid used. In vitro, the acids investigated led to different erosion effects on human dental enamel, despite their equivalent sensorial acidic taste. This has not been reported previously. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  11. Protective Effect of Whole and Fat-Free Fluoridated Milk, Applied before or after Acid Challenge, against Dental Erosion.

    Science.gov (United States)

    Cassiano, Luiza P S; Charone, Senda; Souza, Juliana G; Leizico, Ligia C; Pessan, Juliano P; Magalhães, Ana Carolina; Buzalaf, Marília Afonso Rabelo

    2016-01-01

    This study analysed in vitro the effect of milk against dental erosion, considering three factors: the type of milk (bovine whole/fat-free), the presence of different fluoride concentrations and the time of application (before/after erosive challenge). Bovine enamel (n = 15/group) and root dentine (n = 12/group) specimens were submitted to the following treatments: after the first erosive challenge - 0.9% NaCl solution (negative control), whole milk with 0, 2.5, 5.0 and 10.0 ppm F, fat-free milk with 0, 2.5, 5.0 and 10.0 ppm F, and 0.05% NaF solution (positive control); before the first erosive challenge - whole milk with 0, 2.5, 5.0 and 10.0 ppm F, fat-free milk with 0, 2.5, 5.0 and 10.0 ppm F, and 0.05% NaF solution (positive control). Specimens were submitted to demineralisation-remineralisation regimes 4 times/day for 5 days. The response variables were enamel and dentine loss (in micrometres). Data were analysed using Kruskal-Wallis/Dunn's test (p erosive challenge, was the most protective treatment, but with no significant difference compared with the same treatment carried out after the erosive challenge. For dentine, whole fluoridated milk (all concentrations, after), fat-free 10 ppm F milk (after, before) and whole milk with or without F (except 2.5 ppm F, all before) significantly reduced dentine erosion. It seems that the presence of fluoride, especially at 10 ppm, is the most important factor in reducing dental erosion. © 2016 S. Karger AG, Basel.

  12. Erosive potential of cola and orange fruit juice on tooth colored ...

    African Journals Online (AJOL)

    Background: Erosion is a common condition which manifests due to consumption of high caloric and low pH acidic food stuffs such as carbonated drinks and fruit juices which cause irreversible damage to dental hard tissues and early deterioration of the dental restorations. Aim: The main aim of this study is to evaluate and ...

  13. A simple, sensitive and non-destructive technique for characterizing bovine dental enamel erosion: attenuated total reflection Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Kim, In-Hye; Son, Jun Sik; Min, Bong Ki; Kim, Young Kyoung; Kim, Kyo-Han; Kwon, Tae-Yub

    2016-03-30

    Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Deionized water (control) and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth (110) were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 °C. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers' microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ν1, ν3 phosphate contour: the ratio of the height amplitude of ν3 PO4 to that of ν1 PO4 (Method 1) and the shift of the ν3 PO4 peak to a higher wavenumber (Method 2). The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy (Perosion.

  14. Fluoride Varnishes against Dental Erosion Caused by Soft Drink Combined with Pediatric Liquid Medicine.

    Science.gov (United States)

    Alexandria, Adílis Kalina; Valença, Ana Maria Gondim; Cabral, Lúcio Mendes; Maia, Lucianne Cople

    2017-01-01

    The present study evaluated the effect of NaF and CPP-ACP/NaF varnishes to reduce erosion produced by soft drink (SD) combined or not with pediatric liquid medicine. Enamel specimens were pre-treated with fluoride varnish, according to the following groups: NaF varnish (Duraphat®) or CPP-ACP/NaF varnish (MI varnishTM). Two types of erosive cycles were made: by soft drink erosion (SDE) or by pediatric liquid medicine plus soft drink erosion (PLM/SDE). Bovine enamel specimens were randomly assigned in six groups (n=10): G1=NaF + SDE; G2=CPP-ACP/NaF + SDE; G3=Distilled and deionized (DD) water + SDE; G4=NaF + PLM/SDE; G5=CPP-ACP/NaF + PLM/SDE and G6=DD water + PLM/SDE. Before treatments, the sample surface was divided in two areas (unexposed area-UA and exposed area-EA). The specimens were evaluated by 3D non-contact profilometry technique to determinate tooth structure loss (TSL) and surface roughness (Sa). Scanning electron microscopy (SEM) analysis was also performed. After SDE, G2 presented the lowest TSL values compared to G3 (p=0.008). G1 and G2 did not differ between them (p=0.203) and no groups differed among them despite Sa. Regarding TSL and Sa, G4 and G5 differed from G6 (p=0.0001), but not between them (p=1.00). Examining 3D and SEM images, the greatest differences between UA and EA were observed for G3 and G6. CPP-ACP/NaF varnish seems to be a promising treatment to reduce enamel loss from the erosion produced by a soft drink. Both varnishes also showed capacity to reduce TSL and Sa after erosion by soft drink combined to pediatric liquid medicine.

  15. Influência da dieta líquida ácida no desenvolvimento de erosão dental Influence of the liquid acid diet on the development of dental erosion

    Directory of Open Access Journals (Sweden)

    Maria Angela Pita SOBRAL

    2000-12-01

    cause demineralization. Dietary counseling is an important factor in the treatment and prevention of dental erosion.

  16. Use of dentifrices to prevent erosive tooth wear: harmful or helpful?

    Directory of Open Access Journals (Sweden)

    Ana Carolina Magalhães

    2014-01-01

    Full Text Available Dental erosion is the loss of dental hard tissues caused by non-bacterial acids. Due to acid contact, the tooth surface becomes softened and more prone to abrasion from toothbrushing. Dentifrices containing different active agents may be helpful in allowing rehardening or in increasing surface resistance to further acidic or mechanical impacts. However, dentifrices are applied together with brushing and, depending on how and when toothbrushing is performed, as well as the type of dentifrice and toothbrush used, may increase wear. This review focuses on the potential harmful and helpful effects associated with the use of dentifrices with regard to erosive wear. While active ingredients like fluorides or agents with special anti-erosive properties were shown to offer some degree of protection against erosion and combined erosion/abrasion, the abrasive effects of dentifrices may increase the surface loss of eroded teeth. However, most evidence to date comes from in vitro and in situ studies, so clinical trials are necessary for a better understanding of the complex interaction of active ingredients and abrasives and their effects on erosive tooth wear.

  17. In vitro study on dental erosion provoked by various beverages using electron probe microanalysis.

    Science.gov (United States)

    Willershausen, B; Schulz-Dobrick, B

    2004-09-29

    Tooth erosion is often based on chemical processes, among others the use of soft drinks or diverse beverages. The aim of this in vitro study was to analyse the erosive potential of different acidic beverages. Over a time span of 6 hours, dental slices (n=6 slices per tooth) from fully retained wisdom teeth were incubated with different beverages (coca cola, ice tea with lemon, apple juice and white wine). The controls were incubated with a 0.9% sodium chloride solution under the same conditions (37 degrees C, humidified atmosphere of 5% CO2 and 95% air). The quantitative elementary analysis for calcium, phosphorus, oxygen and other trace elements in the dental slices in various depths ranging from 5 to 50 microm was carried out using an electron probe micro-analyser (Jeol JXA 8900RL). A beverage-induced loss of minerals, particularly of the 2 main components calcium and phosphorus, especially in the uppermost layers of the enamel down to a depth of 30 microm could be observed. In the depth of 10 microm, the following total mineral loss could be determined: white wine (16%), coca cola (14.5%), apple juice (6.5%) and ice tea with lemon (6.5%). A direct correlation between the loss of minerals and the pH value of the beverages was not observed, because of the buffering effect of the drinks. The conversion of the weight percentages from the chemical analysis of Ca and P to their atomic percentages showed that during erosion the 2 main components were not dissolved in significantly different percentages. In this study the erosive potential of the tested soft drinks and other beverages could be demonstrated. However, it must be considered that numerous modifying factors influence the enamel surface, so an extrapolation from the in vitro study to an in vivo situation can only be applied with caution.

  18. Gully erosion in Madagascar: causes and impacts

    Science.gov (United States)

    Raveloson, Andrea; Székely, Balázs; Visnovitz, Ferenc

    2017-04-01

    Soil erosion has been recognized as the main cause of land degradation worldwide and gully erosion is currently considered as one of the most impressive and striking erosion type. This global environmental problem has numerous causes (both natural and anthropogenic) and inflict serious socio-economic problems all around the world. The present study aims to discuss the occurrence and environmental issues related to lavakization in Madagascar and its impact on landscape (badland formation), land use management, flora and fauna, infrastructures, soil properties and human life itself. We assembled and reviewed lavaka researches since 1953. Exact location of the field surveys, cited triggering factors and results of these scientific papers have been studied in detail and compared with our data collected using satellite imagery. Lavaka distribution was analyzed using GIS methods and the relation between their density and different factors was studied. An overview of the many contributing factors (climate, topography, geology, vegetation cover, fault systems, tectonism and land use including inappropriate cultivation and irrigation systems) is given in order to better understand lavaka formation, distribution and impacts. Synthesis of previous researches might help us define area susceptible to gully formation. This can be used to determine prevention priorities for farmers, to manage their lands sustainably. This is ILARG contribution 18.

  19. Erosion of a grooved surface caused by impact of particle-laden flow

    Science.gov (United States)

    Jung, Sohyun; Yang, Eunjin; Kim, Ho-Young

    2016-11-01

    Solid erosion can be a life-limiting process for mechanical elements in erosive environments, thus it is of practical importance in many industries such as construction, mining, and coal conversion. Erosion caused by particle-laden flow occurs through diverse mechanisms, such as cutting, plastic deformation, brittle fracture, fatigue and melting, depending on particle velocity, total particle mass and impingement angle. Among a variety of attempts to lessen erosion, here we investigate the effectiveness of millimeter-sized grooves on the surface. By experimentally measuring the erosion rates of smooth and triangular-grooved surfaces under various impingement angles, we find that erosion can be significantly reduced within a finite range of impingement angles. We show that such erosion resistance is attributed to the swirls of air within grooves and the differences in erosive strength of normal and slanted impact. In particular, erosion is mitigated when we increase the effective area under normal impact causing plastic deformation and fracture while decreasing the area under slanted impact that cuts the surface to a large degree. Our quantitative model for the erosion rate of grooved surfaces considering the foregoing effects agrees with the measurement results.

  20. Erosi Tanah Akibat Operasi Pemanenan Hutan (Soil Erosion Caused by Forest Harvesting Operations

    Directory of Open Access Journals (Sweden)

    Ujang Suwarna

    2011-05-01

    Full Text Available Forest harvesting operation has been known as an activity that should be considered as the main cause of soil erosion. Indonesia, the second largest owner of tropical forest, should have a serious consideration to the operation.  Therefore, the study was conducted in logged over area of a natural production forest.  The objectives of the study was to examine level of soil erosion caused by forest harvesting operations and to analyze a strategy to control level of the erosion based on its influencing factors. The study showed that forest harvesting operations caused soil erosion.  Factors that influenced the high level of the erosion were high level of precipitation, lack on planning of forest harvesting operations, no applying treatment of cross drain and cover crop in the new skidding roads, no culture of carefulness in the operations, and low human resource capacity in applying environmentally friendly forest harvesting techniques. Keywords: soil erosion, forest harvesting, logged over area, skidding road

  1. Food acid content and erosive potential of sugar-free confections.

    Science.gov (United States)

    Shen, P; Walker, G D; Yuan, Y; Reynolds, C; Stacey, M A; Reynolds, E C

    2017-06-01

    Dental erosion is an increasingly prevalent problem associated with frequent consumption of acidic foods and beverages. The aim of this study was to measure the food acid content and the erosive potential of a variety of sugar-free confections. Thirty sugar-free confections were selected and extracts analysed to determine pH, titratable acidity, chemical composition and apparent degree of saturation with respect to apatite. The effect of the sugar-free confections in artificial saliva on human enamel was determined in an in vitro dental erosion assay using change in surface microhardness. The change in surface microhardness was used to categorize the confections as high, moderate or low erosive potential. Seventeen of the 30 sugar-free confections were found to contain high concentrations of food acids, exhibit low pH and high titratable acidity and have high erosive potential. Significant correlations were found between the dental erosive potential (change in enamel surface microhardness) and pH and titratable acidity of the confections. Ten of these high erosive potential confections displayed dental messages on the packaging suggesting they were safe for teeth. Many sugar-free confections, even some with 'Toothfriendly' messages on the product label, contain high contents of food acids and have erosive potential. © 2017 Australian Dental Association.

  2. Prevalence of dental erosion among 18-year-old adolescents in the borderland districts of Lviv (Ukraine) and Lublin (Poland).

    Science.gov (United States)

    Bachanek, Teresa; Hendzel, Barbara; Wolańska, Ewa; Szybinsky, Volodymir; Ogonovsky, Roman; Hrynovets, Volodymir; Samborski, Dariusz; Nakonieczna-Rudnicka, Marta; Chałas, Renata

    2018-03-14

    Recent epidemiological studies have shown an association between dental erosion occurrence and changes in lifestyle and dietary habits in both developed and developing countries, and now affects different regions of the world. Furthermore, in current literature, studies have shown that the prevalence of erosive tooth wear has increased particularly among the younger population. The aim of the study was to assess the prevalence and severity of erosive tooth wear among 18-year-old adolescents in the districts of Lviv (Ukraine) and Lublin (Poland). College students (254 subjects) aged 18, living in the Lviv and Lublin districts were examined. Erosive lesions presented in the teeth were assessed on the basis of the BEWE (Basic Erosive Wear Examination) index. Among the 137 patients living in the Lublin district, 70 were females and 67 were males, while in the Lviv district, 60 women and 57 men were examined. In both districts, the following numbers of rural patients were examined: 66 in Lublin district and 56 in Lviv district; for urban inhabitants, the numbers were 71 in Lublin and 61 in Lviv. Analysing the BEWE values, it was noted that higher BEWE values, and resulting from them significant differences were observed in both male and female groups living in Lublin, compared with Lviv inhabitants. Based on clinical examination and statistical analysis, the occurrence of lesions of an erosive character in at least one sextant were observed in 59.85% of patients from Lublin district, and in 42.74% of patients from Lviv district. On the basis of the conducted study in the Polish and Ukrainian groups of 18-year-old adolescents living on the borderland, it can be stated that dental erosion is a problem noticeable in both groups of cohorts, but with higher prevalence in the Lublin district.

  3. Dental erosion in the 21st century: what is happening to nutritional habits and lifestyle in our society?

    NARCIS (Netherlands)

    Gambon, D.L.; Brand, H.S.; Veerman, E.C.I.

    2012-01-01

    Several developments in Western Europe may have contributed to the increased prevalence of dental erosion during the last decades. Exposing children to sour taste at an early age increases the preference for acidic food and drinks later in life. Acidic fruits and beverages became widely available

  4. Erosive effects of common beverages on extracted premolar teeth.

    Science.gov (United States)

    Seow, W K; Thong, K M

    2005-09-01

    Dental erosion is highly prevalent today, and acidic drinks are thought to be an important cause. The aim of the present investigation was to determine the erosive potential of a range of common beverages on extracted human teeth. The beverages were tested for their individual pHs using a pH meter. The clinical effects of the most erosive beverages were determined by the degree of etching and Vickers microhardness of enamel. The results showed that many common beverages have pHs sufficiently low to cause enamel erosion. Lime juice concentrate (pH 2.1) had the lowest pH, followed by Coca-cola and Pepsi (both with pH 2.3) and Lucozade (pH 2.5). The erosive potential of these beverages was demonstrated by the deep etching of the enamel after five minutes. The Vickers Hardness of enamel was reduced by about 50 per cent in the case of lime juice (p case of Coca-cola (p Coca-cola completely reversed the erosive effects on the enamel. Although only a few of the beverages with the lowest pHs were tested, the present study showed that the most acidic drinks had the greatest erosive effects on enamel. While saliva was protective against erosion, relatively large volumes were required to neutralize the acidity.

  5. The effects of acid erosion and remineralization on enamel and three different dental materials: FT-Raman spectroscopy and scanning electron microscopy analysis.

    Science.gov (United States)

    Soares, Luís Eduardo Silva; Soares, Ana Lúcia Silva; De Oliveira, Rodrigo; Nahórny, Sidnei

    2016-07-01

    FT-Raman spectroscopy and scanning electron microscopy (SEM) were employed to test the hypothesis that the beverage consumption or mouthwash utilization would change the chemistry of dental materials and enamel inorganic content. Bovine enamel samples (n = 36) each received two cavity preparations (n = 72), each pair filled with one of three dental materials (R: nanofilled composite resin, GIC: glass-ionomer cement, RMGIC: resin-modified GIC). Furthermore, they were treated with three different solutions (S: artificial saliva, E: erosion/Pepsi Twist or EM: erosion + mouthwash/Colgate Plax). Reduction of carbonate content of enamel was greater in RE than RS (P erosion. Material degradation was greater after E and EM than S. GIC and RMGIC materials had a positive effect against acid erosion in the adjacent enamel after remineralization with mouthwash. The beverage and mouthwash utilization would change R and GIC chemical properties. A professional should periodically monitor the glass-ionomer and resin restorations, as they degrade over time under erosive challenges and mouthwash utilization. Microsc. Res. Tech., 2016. © 2016 Wiley Periodicals, Inc. Microsc. Res. Tech. 79:646-656, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Management of dental erosion induced by gastro-esophageal reflux disorder with direct composite veneering aided by a flexible splint matrix.

    Science.gov (United States)

    Chockattu, Sherin Jose; Deepak, Byathnal Suryakant; Sood, Anubhav; Niranjan, Nandini T; Jayasheel, Arun; Goud, Mallikarjun K

    2018-02-01

    Dental erosion is frequently overlooked in clinical practice. The management of erosion-induced damage to the dentition is often delayed, such that extensive occlusal rehabilitation is required. These cases can be diagnosed by a careful clinical examination and a thorough review of the patient's medical history and/or lifestyle habits. This case report presents the diagnosis, categorization, and management of a case of gastro-esophageal reflux disease-induced palatal erosion of the maxillary teeth. The early management of such cases is of utmost importance to delay or prevent the progression of damage both to the dentition and to occlusal stability. Non-invasive adhesively bonded restorations aid in achieving this goal.

  7. Remineralizing effect of a zinc-hydroxyapatite toothpaste on enamel erosion caused by soft drinks: Ultrastructural analysis.

    Science.gov (United States)

    Colombo, Marco; Mirando, Maria; Rattalino, Davide; Beltrami, Riccardo; Chiesa, Marco; Poggio, Claudio

    2017-07-01

    The aim of the present in vitro study was to evaluate the protective effects of a zinc-hydroxyapatite toothpaste on repairing enamel erosion produced by a soft drink (Coca-Cola) compared to toothpastes with and without fluoride using Scanning Electron Microscopy (SEM). Fifty specimens were assigned to 5 groups of 10 specimens each. (Group 1: no erosive challenge, no toothpaste treatment, group 2: erosive challenge, no toothpaste treatment, 3: erosive challenge, toothpaste without fluoride, group 4: erosive challenge, fluoride toothpaste treatment, group 5: erosive challenge, zinc-hydroxyapatite toothpaste treatment). Repeated erosive challenges were provided by immersing bovine enamel specimens (10 per group) in a soft drink for 2 min (6mL, room temperature) at 0, 8, 24 and 32 h. After each erosive challenge, the toothpastes were applied neat onto the surface of specimens for 3 min without brushing and removed with distilled water. Between treatments the specimens were kept in artificial saliva. The surface of each specimen was imaged by SEM. Statistically significant differences were found between the samples used as control and those immersed in Coca-Cola (group 1 and 2): indeed among all groups the highest grade of damage was found in group 2. Instead the lowest grade was recorded in the samples of group 5 (Zinc hydroxyapatite toothpaste). The results of this study confirmed the potential benefit the Zn-HAP technology could provide in protecting enamel from erosive acid challenges. The treatment of erosively challenged enamel with Zn-Hap toothpaste showed a clear protective effect. Key words: Dental erosion, enamel, SEM, toothpaste.

  8. Laser speckle imaging: a novel method for detecting dental erosion.

    Directory of Open Access Journals (Sweden)

    Nelson H Koshoji

    Full Text Available Erosion is a highly prevalent condition known as a non-carious lesion that causes progressive tooth wear due to chemical processes that do not involve the action of bacteria. Speckle images proved sensitive to even minimal mineral loss from the enamel. The aim of the present study was to investigate the use of laser speckle imaging analysis in the spatial domain to quantify shifts in the microstructure of the tooth surface in an erosion model. 32 fragments of the vestibular surface of bovine incisors were divided in for groups (10 min, 20 min. 30 min and 40 min of acid etching immersed in a cola-based beverage (pH approximately 2.5 twice a day during 7 days to create an artificial erosion. By analyzing the laser speckle contrast map (LASCA in the eroded region compared to the sound it was observed that the LASCA map shifts, proportionally to the acid each duration, by: 18%; 23%; 39% and 44% for the 10 min; 20 min; 30 min and 40 min groups, respectively. To the best of our knowledge, this is the first study to demonstrate the correlation between speckle patterns and erosion progression.

  9. Dental erosion in the 21st century: what is happening to nutritional habits and lifestyle in our society?

    Science.gov (United States)

    Gambon, D L; Brand, H S; Veerman, E C I

    2012-07-27

    Several developments in Western Europe may have contributed to the increased prevalence of dental erosion during the last decades. Exposing children to sour taste at an early age increases the preference for acidic food and drinks later in life. Acidic fruits and beverages became widely available due to economic prosperity. New types of acidic candies were developed, some of which are kept in the mouth for very long times. Children are exposed to intense marketing of these acidic products, which are widely available in supermarkets and school canteens. In the meantime, much less attention has been paid to the development and marketing of less erosive food products.

  10. The Effect of Casein Phosphopeptide-Amorf Calcium Phosphate and Acidulated Phosphate Fluoride Gel on Dental Erosion in Primary Teeth: An in Vitro Study.

    Science.gov (United States)

    Maden, Eda Arat; Acar, Özge; Altun, Ceyhan; Polat, Günseli Güven

    This study aimed to investigate the effect of acidulated phosphate fluoride (APF) gel and casein phosphopeptide/amorphous calciumphosphate (CPP-ACP) on the dental erosion produced by carbonated soft drink in primary teeth. This study evaluated by an in vitro model the effect of APF gel and CPP-ACP on the dental enamel previously subjected to erosive challenge with carbonated soft drink. Sixty sound human primary molars were prepared by embedding the crown sections in acrylic resin blocks leaving the enamel surfaces exposed. The surface roughness of the enamel was measured with prophilometry at baseline. Specimens were randomly divided into three treatment groups (n:20): artificial saliva, CPP-ACP, 1.23% APF gel. All specimens were then exposed to an erosive challenge of carbonated soft drink and artificial saliva for 20 cycles of 20 seconds each. Demineralization-remineralization cycles was repeated twice at eight-hour intervals and roughness values were measured. Enamel samples were treated with artificial saliva, CPP-ACP, 1.23% APF gel applied for 10 min after erosive challenge. The arithmetic average roughness (Ra) readings were recorded after remineralization agents were applied. The mean surface roughness in all groups increased significantly after erosion process and decreased after remineralization treatment. After treatment, the mean surface roughness of the 1.23% APF gel group was significantly less than the other groups and the mean surface roughness of the artificial saliva group was significantly more than the other groups. 1.23% APF gel showed the highest protective effect against erosive enamel loss. Under the conditions of this study, artificial saliva, CPP-ACP and 1.23% APF treatments were able to reduce erosive enamel loss produced by carbonated soft drink in primary teeth. However, 1.23% APF gel showed the highest protective effect against erosive enamel loss.

  11. Analysis of the Early Stages and Evolution of Dental Enamel Erosion.

    Science.gov (United States)

    Derceli, Juliana Dos Reis; Faraoni, Juliana Jendiroba; Pereira-da-Silva, Marcelo Assumpção; Palma-Dibb, Regina Guenka

    2016-01-01

    The aim of this study was to evaluate by atomic force microscopy (AFM) the early phases and evolution of dental enamel erosion caused by hydrochloric acid exposure, simulating gastroesophageal reflux episodes. Polished bovine enamel slabs (4x4x2 mm) were selected and exposed to 0.1 mL of 0.01 M hydrochloric acid (pH=2) at 37 ?#61472;?#61616;C using five different exposure intervals (n=1): no acid exposure (control), 10 s, 20 s, 30 s and 40 s. The exposed area was analyzed by AFM in 3 regions to measure the roughness, surface area and morphological surface. The data were analyzed qualitatively. Roughness started as low as that of the control sample, Rrms=3.5 nm, and gradually increased at a rate of 0.3 nm/s, until reaching Rrms=12.5 nm at 30 s. After 40 s, the roughness presented increment of 0.40 nm only. Surface area (SA) increased until 20 s, and for longer exposures, the surface area was constant (at 30 s, SA=4.40 μm2 and at 40 s, SA=4.43 μm2). As regards surface morphology, the control sample presented smaller hydroxyapatite crystals (22 nm) and after 40 s the crystal size was approximately 60 nm. Short periods of exposure were sufficient to produce enamel demineralization in different patterns and the morphological structure was less affected by exposure to hydrochloric acid over 30 s.

  12. The effect of pH on the erosion of dentine and enamel by dietary acids in vitro.

    Science.gov (United States)

    West, N X; Hughes, J A; Addy, M

    2001-09-01

    The reported incidence of tooth erosion caused by acidic soft drinks has been increasingly documented. Citric and phosphoric acids are the two main dietary acids present in these soft drinks. Many variables need to be determined in order to assess risk factors for dental erosion caused by beverage consumption including pH, titratable acidity, pKa, buffering capacity, hence the aim of these in vitro investigations. Methodologies included profiling flat enamel and dentine samples (acidic solutions adjusted with alkali over the available pH range; citric, phosphoric and hydrochloric acid were adjusted with sodium hydroxide and citric acid with trisodium citrate. Tissue loss was calculated by profilometry. Results showed that under these conditions citric acid caused far more erosion over the pH range employed than phosphoric acid for both tissue types. Citric acid compared with hydrochloric acid highlighted dissolution and chelation effects. Phosphoric acid caused minimal erosion over pH 3 for enamel and pH 4 for dentine. These factors could be considered in order to reduce the erosivity of acidic soft drinks.

  13. The Impact of Selected Fluoridated Toothpastes on Dental Erosion in Profilometric Measurement.

    Science.gov (United States)

    Fita, Katarzyna; Kaczmarek, Urszula

    2016-01-01

    Some fluoridated toothpastes, available commercially, are described to have a protective effect against dental erosion. To evaluate the influence of the selected marketed toothpastes on the human enamel exposed to acid beverages. Enamel specimens from extracted human teeth were prepared (n = 40). Specimens were randomly divided into 10 experimental groups, 4 specimens each, which were subjected to acid challenge for 10 min using orange juice (pH 3.79) or Pepsi Cola (pH 2.58) and then immersed for 2 min into a slurry of five marketed toothpastes with distilled water (1 : 3 w/w). The tested toothpastes contained 1450 or 5000 ppm fluoride, CPP-ACP with 900 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5%, all of them as sodium fluoride, and 700 ppm fluoride as amine and sodium fluoride with 3500 ppm SnCl2. Enamel roughness (Ra parameter) by contact profilometer at baseline and after exposure onto soft drinks and slurry was measured. Exposure to both beverages caused a similar increase of enamel surface roughness. After the specimens immersion into slurries of toothpastes with 1450 or 5000 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5% and CPP-ACP with 900 ppm fluoride the significant decrease of Ra values were found, reaching the baseline values. However, toothpaste with 700 ppm fluoride and 3500 ppm SnCl2 did not cause any fall in Ra value, probably due to other mechanism of action. Within the limitation of the study we can conclude that the sodium fluoride toothpastes are able to restore the surface profile of enamel exposed shortly to acidic soft drinks.

  14. Processes and Causes of Accelerated Soil Erosion on Cultivated ...

    African Journals Online (AJOL)

    Processes and Causes of Accelerated Soil Erosion on Cultivated Fields of South Welo, Ethiopia. ... In most of the highlands, crop cultivation is carried out without any type of terracing, while about 74 per cent of this land requires application of contour plowing, broad-based terracing, or bench terracing. The third group of ...

  15. ON THE EROSIVE EFFECT OF SOME BEVERAGES FOR SPORTSMEN UPON DENTAL ENAMEL

    Directory of Open Access Journals (Sweden)

    Cosmin ARNAUTEANU

    2015-06-01

    Full Text Available The aim of the study was to compare the surface morphology of enamel and the variation of the mineral ions concentration after the manifestation of the erosive effect determined by various commercial beverages for athletes. 14 premolars extracted from orthodontic reasons have been cut in two halves. On each section, an enamel surface of 3x3 mm was preserved for investigations. The samples have been divided into 4 groups. In the control group, the 7 sections were kept in artificial saliva while, in the other 3 groups, the sections were introduced in 3 beverages for athletes: Gatorade Citron (Pepsi Cola Co., 5-hour Energy (Living Essentials, Powerade Cherry (Coca Cola Co.. The samples were analyzed on an electronic microscope with Vega II LSH scanning device, coupled with EDX Quantax QX2 detector. SEM analysis evidenced erosion zones at the level of enamel, which appears pinched in the samples subjected to the action of acid beverages. A decreasing tendency of the average values of calcium ion concentrations was observed in the batches in which the enamel samples had been subjected to the action of beverages for athletes. The highest relative variations of calcium and phosphorous ions (10%, respectively 8% were recorded for Gatorade, followed, in decreasing order, by Powerade, for which variations of 9%, respectively 6%, were noticed, and by the 5-hour Energy beverage, in which the relative losses were of 5%, respectively 3%. All beverages for athletes tested in the present study showed erosion potential upon the dental enamel. Gatorade appeared as the most aggressive beverage for athletes followed by Powerade and 5-hour Energy.

  16. Dental erosion and severe tooth decay related to soft drinks: a case report and literature review*

    OpenAIRE

    Cheng, Ran; Yang, Hui; Shao, Mei-ying; Hu, Tao; Zhou, Xue-dong

    2009-01-01

    Soft drinks have many potential health problems. The inherent acids and sugars have both acidogenic and cariogenic potential, resulting in dental caries and potential enamel erosion. In this report we present a 25-year-old man complaining with the severe worn-out of the front teeth during the past 3 years. He had a history of drinking cola for more than 7 years and had a poor oral hygiene. Severe decays were present in the incisors and the canines, while less severe lesions were noted on the ...

  17. Erosion and sedimentation caused by watercourse regulation

    International Nuclear Information System (INIS)

    Dahl, T.E.; Godtland, K.

    1995-01-01

    This report describes the observations made by SINTEF NHL in 1993 - 1994 on the development of erosion in three regulated lakes in Norway: Devdesjavri, Store Maalvatn and Gjevilvatnet. Surveys, profile levelling, water sample analyses, aerial photography etc were all used. Erosion was dramatic in all three magazines the first year of regulation and then slowed down. It has since remained relatively stable. However, there is a risk of further strong erosion connected with flooding tributaries, notably at low water such as usually occurs in spring. This is true in particular of the main river discharging into Devdesjavri, which is subject to landslides, wave and river erosion. In addition, ground water erosion may occur if the magazine is drained too fast. The report is lavishly illustrated with colour pictures of the effects of erosion. 21 refs., 15 figs., 13 tabs

  18. Genetic variation may explain why females are less susceptible to dental erosion.

    Science.gov (United States)

    Uhlen, Marte-Mari; Stenhagen, Kjersti R; Dizak, Piper M; Holme, Børge; Mulic, Aida; Tveit, Anne B; Vieira, Alexandre R

    2016-10-01

    Not all individuals at risk for dental erosion (DE) display erosive lesions. The prevalence of DE is higher among male subjects. The occurrence of DE may depend on more than just acidic challenge, with genetics possibly playing a role. The aim of this study was to investigate the association of enamel-formation genes with DE. One premolar and a saliva sample were collected from 90 individuals. Prepared teeth were immersed in 0.01 M HCl (pH 2.2), and enamel loss (μm) was measured using white light interferometry. DNA was extracted from saliva, and 15 single-nucleotide polymorphisms were analysed. Allele and genotype frequencies were related to the enamel loss of the specimens. Single-marker and haplotype analyses were performed using sex as a covariate. Mean enamel loss was higher for male donors than for female donors (P = 0.047). Significant associations were found between enamel loss and amelogenin, X-linked (AMELX), tuftelin 1 (TUFT1), and tuftelin-interacting protein 11 (TFIP11). Analyses showed significant associations between variation in enamel-formation genes and a lower susceptibility to DE in female subjects. The results indicate that susceptibility to DE is influenced by genetic variation, and may, in part, explain why some individuals are more susceptible than others to DE, including differences between female subjects and male subjects. © 2016 Eur J Oral Sci.

  19. Relationship between food habits and tooth erosion occurrence in Malaysian University students.

    Science.gov (United States)

    Manaf, Zahara Abdul; Lee, Mei Tee; Ali, Nor Hazirah Muhammad; Samynathan, Selvamary; Jie, Ying Phor; Ismail, Noor Hasnani; Bibiana Hui Ying, Yong; Wei Seng, Yeo; Yahya, Nurul Asyikin

    2012-04-01

    Tooth erosion is a growing dental problem; however, the role of diet in the aetiology of tooth erosion is unclear. A cross-sectional study was conducted to determine the association between tooth erosion occurrence and the consumption of acidic foods and drinks among undergraduate university students. A total of 150 undergraduate students (33 males and 117 females) aged 19 to 24 years at Universiti Kebangsaan Malaysia participated in this study. The Basic Erosive Wear Examination was used to assess the occurrence of tooth erosion. Information regarding dental hygiene practices, usual dietary habits, and consumption of acidic foods and drinks was obtained through a structured questionnaire. In all, 68% of subjects had tooth erosion. Subjects who reported having received information about healthy eating were less likely to have tooth erosion (χ(2) [1, N = 150] = 7.328, P = 0.007). The frequencies of milk (OR = 0.29, 95% CI = 0.13-0.67) and tea/coffee (adjusted OR = 0.42, 95% CI = 0.19-0.95) consumption were negatively associated with tooth erosion. Dental hygiene practice, the frequency and amount of acidic food and drink intake, and body mass index classification were not significantly associated with the risk of tooth erosion (P > 0.05). A high prevalence of tooth erosion was observed among this group of students. Preventive measures, such as dietary advice and increased consumption of milk at a younger age, may reduce the occurrence of tooth erosion among this age group.

  20. Application of the specular and diffuse reflection analysis for in vitro diagnostics of dental erosion: correlation with enamel softening, roughness, and calcium release

    Science.gov (United States)

    Rakhmatullina, Ekaterina; Bossen, Anke; Höschele, Christoph; Wang, Xiaojie; Beyeler, Barbara; Meier, Christoph; Lussi, Adrian

    2011-10-01

    We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r2 >= -0.86) as well as calcium release (r2 >= -0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r2 = 0.42-0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo.

  1. Erosion of Brassica incana Genetic Resources: Causes and Effects

    Science.gov (United States)

    Muscolo, A.; Settineri, G.; Mallamaci, C.; Papalia, T.; Sidari, M.

    2017-07-01

    Brassica incana Ten., possessing a number of useful agronomic traits, represents a precious genetic resource to be used in plant breeding programs to broaden the genetic base in most Brassica crop species. B. incana that grows on limestone cliffs is at risk of genetic erosion for environmental constraints and human activities. We studied the pedological conditions of a Calabrian site where the B. incana grows, and we correlated the soil properties to the physiological and biochemical aspects of B. incana to identify the causes and effects of the genetic erosion of this species. Our results evidenced that physical soil conditions did not affect B. incana growth and nutraceutical properties; conversely, biological soil properties modified its properties. We identified leaf pigments and secondary metabolites that can be used routinely as early warning indicators of plant threat, to evaluate in a short term the dynamic behavior of plants leading to species extinction.

  2. Erhversbetinget erosion?

    DEFF Research Database (Denmark)

    Dige, Irene; Gjørup, Hans; Nyvad, Bente

    2012-01-01

    Baggrund – I forbindelse med dental erosion er en grundig udredning af patienten vigtig, således at årsagen til erosionernes opståen findes, og der kan iværksættes adækvat forebyggende indsats. En sådan udredning er ikke mindst vigtig, når arbejdsmiljøet mistænkes. Patienttilfælde – En 30-årig...... arbejdsskade, men ikke anerkendt, da erosioner ikke er optaget på Arbejdsskadestyrelsens liste over erhvervssygdomme. En systematisk registrering af lignende tilfælde kunne imidlertid på sigt ændre retspraksis for fremtidige patienter med arbejdsbetinget erosion....... patient, der arbejder som pladesmed, blev henvist til Landsdels- og Videnscenter, Århus Sygehus, med henblik på udredning af patientens kraftige slid. Patienten udviste ikke-alderssvarende tandslid af emalje og dentin svarende til erosion forårsaget af syredampe i arbejdsmiljøet, muligvis forstærket af...

  3. Bone erosion and subacromial bursitis caused by diphtheria-tetanus-poliomyelitis vaccine.

    Science.gov (United States)

    Salmon, J H; Geoffroy, M; Eschard, J P; Ohl, X

    2015-11-17

    Revaxis(®) is a vaccine against diphtheria, tetanus and poliomyelitis (dT-IPV). This vaccine should not be administered by the intradermal or intravenous route. Poor injection techniques and related consequences are rare. We report a case of bursitis associated with reactive glenohumeral effusion complicated by bone erosion occurring after injection of the dT-IPV vaccine. A 26 year old patient was admitted for painful left shoulder causing functional impairment. Control magnetic resonance imaging showed bone oedema on the upper outer part of the humeral head, with a slight cortical irregularity, indicating that the vaccine was injected in contact with the bone at this location, causing erosion. Outcome was favourable after intra-articular corticosteroids. Reports of articular or periarticular injury after vaccination are extremely rare, in view of the substantial number of vaccines administered every year. The potential complications of vaccination are well known to general practitioners but under-reported in the literature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Erosion of buffer caused by groundwater leakages

    International Nuclear Information System (INIS)

    Autio, J.; Hanana, K.; Punkkinen, O.; Koskinen, K.; Olin, M.

    2010-01-01

    Document available in extended abstract form only. In the Finnish HLW disposal concept the most important properties of the bentonite clay being considered for these isolation purposes are its thermal behaviour, low hydraulic conductivity, diffusion limited transport, rheology, plasticity, sufficient swelling potential, and exchange capacity. All of these properties depend critically on bentonite density; therefore, any potential mass loss or redistribution events must be well characterized. One such event or process is the erosion of bentonite by flowing groundwater and the groundwater flowing in newly formed channels, in special. Mechanical erosion during the operational phase, due to high groundwater pressure gradients in open excavations, has been identified as a critical issue in TKS-2006 and SR-Can. This work addresses the mechanical erosion of bentonite by fluid shear. In order for buffer erosion to occur three processes must take place: detachment, entrainment, and transport. These processes are followed by the settling of the material and redistribution of buffer mass. Erosion begins with the detachment of a particle from surrounding material, which requires the application of shear forces greater than the attractive force between the particle and parent structure. Entrainment is the process by which the eroding medium lifts the detached particle into the flow. The most important aspect in entrainment is transfer of fluid's inertial forces via surface friction to particles' inertial forces, which, in turn, must overcome the frictional resistance between the particle and its surroundings. Factors influencing frictional resistance include gravity, particle mass, saturation degree of parent structure, composition of water present in parent structure, particle size, and surface roughness. Recent erosion tests, whereby water flow was directed over compacted bentonite blocks or through a system of bentonite pellets, have indicated that bentonite erodes

  5. The impact of stannous, fluoride ions and its combination on enamel pellicle proteome and dental erosion prevention.

    Directory of Open Access Journals (Sweden)

    A A Algarni

    Full Text Available To compare the effects of stannous (Sn and fluoride (F ions and their combination on acquired enamel pellicle (AEP protein composition (proteome experiment, and protection against dental erosion (functional experiment.In the proteome experiment, bovine enamel specimens were incubated in whole saliva supernatant for 24h for AEP formation. They were randomly assigned to 4 groups (n=10, according to the rinse treatment: Sn (800ppm/6.7mM, SnCl2, F (225ppm/13mM, NaF, Sn and F combination (Sn+F and deionized water (DIW, negative control. The specimens were immersed 3× in the test rinses for 2min, 2h apart. Pellicles were collected, digested, and analyzed for protein content using liquid chromatography electrospray ionization tandem mass spectrometry. In the functional experiment, bovine enamel specimens (n=10 were similarly treated for pellicle formation. Then, they were subjected to a five-day erosion cycling model, consisting of 5min erosive challenges (15.6 mM citric acid, pH 2.6, 6×/d and 2min treatment with the rinses containing Sn, F or Sn+F (3×/d. Between the treatments, all specimens were incubated in whole saliva supernatant. Surface loss was determined by profilometry.Our proteome approach on bovine enamel identified 72 proteins that were common to all groups. AEP of enamel treated with Sn+F demonstrated higher abundance for most of the identified proteins than the other groups. The functional experiment showed reduction of enamel surface loss for Sn+F (89%, Sn (67% and F (42% compared to DIW (all significantly different, p<0.05.This study highlighted that anti-erosion rinses (e.g. Sn+F can modify quantitatively and qualitatively the AEP formed on bovine enamel. Moreover, our study demonstrated a combinatory effect that amplified the anti-erosive protection on tooth surface.

  6. Diet, nutrition and the prevention of dental diseases

    DEFF Research Database (Denmark)

    Moynihan, Paula; Petersen, Poul Erik

    2004-01-01

    on teeth is the local action of diet in the mouth on the development of dental caries and enamel erosion. Dental erosion is increasing and is associated with dietary acids, a major source of which is soft drinks. Despite improved trends in levels of dental caries in developed countries, dental caries......Oral health is related to diet in many ways, for example, nutritional influences on craniofacial development, oral cancer and oral infectious diseases. Dental diseases impact considerably on self-esteem and quality of life and are expensive to treat. The objective of this paper is to review...... the evidence for an association between nutrition, diet and dental diseases and to present dietary recommendations for their prevention. Nutrition affects the teeth during development and malnutrition may exacerbate periodontal and oral infectious diseases. However, the most significant effect of nutrition...

  7. Surface erosion and sedimentation caused by ejecta from the lunar crater Tycho

    Science.gov (United States)

    Shkuratov, Y.; Basilevsky, A.; Kaydash, V.; Ivanov, B.; Korokhin, V.; Videen, G.

    2018-02-01

    We use Kaguya MI images acquired at wavelengths 415, 750, and 950 nm to map TiO2 and FeO content and the parameter of optical maturity OMAT in lunar regions Lubiniezky E and Taurus-Littrow with a spatial resolution of 20 m using the Lucey method [Lucey et al., JGR 2000, 105. 20,297]. We show that some ejecta from large craters, such as Tycho and Copernicus may cause lunar surface erosion, transportation of the eroded material and its sedimentation. The traces of the erosion resemble wind tails observed on Earth, Mars, and Venus, although the Moon has no atmosphere. The highland material of the local topographic prominences could be mobilized by Tycho's granolometrically fine ejecta and caused by its transportation along the ejecta way to adjacent mare areas and subsequent deposition. The tails of mobilized material reveal lower abundances of Ti and Fe than the surrounding mare surface. We have concluded that high-Ti streaks also seen in the Lubiniezky E site, which show unusual combinations of the TiO2 and FeO content on the correlation diagram, could be the result of erosion by Tycho's ejecta too. In these locations, Tycho's material did not form a consolidated deposit, but resulted in erosion of the mare surface material that became intermixed, consequently, diluting the ejecta. The Taurus-Littrow did provide evidence of the mechanical effect of Tycho's ejecta on the local landforms (landslide, secondary craters) and do not show the compositional signature of Tycho's ejecta probably due to intermixing with local materials and dilution.

  8. Application of the specular and diffuse reflection analysis for in vitro diagnostics of dental erosion: correlation with enamel softening, roughness, and calcium release

    Science.gov (United States)

    Rakhmatullina, Ekaterina; Bossen, Anke; Höschele, Christoph; Wang, Xiaojie; Beyeler, Barbara; Meier, Christoph; Lussi, Adrian

    2011-01-01

    We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r2 ≥ −0.86) as well as calcium release (r2 ≥ −0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r2 = 0.42–0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo. PMID:22029364

  9. The effect of antacid on salivary pH in patients with and without dental erosion after multiple acid challenges.

    Science.gov (United States)

    Dhuhair, Sarah; Dennison, Joseph B; Yaman, Peter; Neiva, Gisele F

    2015-04-01

    To evaluate the effect of antacid swish in the salivary pH values and to monitor the pH changes in subjects with and without dental erosion after multiple acid challenge tests. 20 subjects with tooth erosion were matched in age and gender with 20 healthy controls according to specific inclusion/exclusion criteria. Baseline measures were taken of salivary pH, buffering capacity and salivary flow rate using the Saliva Check System. Subjects swished with Diet Pepsi three times at 10-minute intervals. Changes in pH were monitored using a digital pH meter at 0-, 5-, and 10- minute intervals and at every 5 minutes after the third swish until pH resumed baseline value or 45 minutes relapse. Swishing regimen was repeated on a second visit, followed by swishing with sugar-free liquid antacid (Mylanta Supreme). Recovery times were also recorded. Data was analyzed using independent t-tests, repeated measures ANOVA, and Fisher's exact test (α= 0.05). Baseline buffering capacity and flow rate were not significantly different between groups (P= 0.542; P= 0.2831, respectively). Baseline salivary pH values were similar between groups (P= 0.721). No significant differences in salivary pH values were found between erosion and non-erosion groups in response to multiple acid challenges (P= 0.695) or antacid neutralization (P= 0.861). Analysis of salivary pH recovery time revealed no significant differences between groups after acid challenges (P= 0.091) or after the use of antacid (P= 0.118). There was a highly significant difference in the survival curves of the two groups on Day 2, with the non-erosion group resolving significantly faster than the erosion group (P= 0.0086).

  10. The potential effects of pH and buffering capacity on dental erosion.

    Science.gov (United States)

    Owens, Barry M

    2007-01-01

    Soft drink pH (initial pH) has been shown to be a causative factor--but not necessarily the primary initiating factor--of dental erosion. The titratable acidity or buffering capacity has been acknowledged as playing a significant role in the etiology of these lesions. This in vitro study sought to evaluate five different soft drinks (Coca-Cola Classic, Diet Coke, Gatorade sports drink, Red Bull high-energy drink, Starbucks Frappucino coffee drink) and tap water (control) in terms of initial pH and buffering capacity. Initial pH was measured in triplicate for the six beverages. The buffering capacity of each beverage was assessed by measuring the weight (in grams) of 0.10 M sodium hydroxide necessary for titration to pH levels of 5.0, 6.0, 7.0, and 8.3. Coca-Cola Classic produced the lowest mean pH, while Starbucks Frappucino produced the highest pH of any of the drinks except for tap water. Based on statistical analysis using ANOVA and Fisher's post hoc tests at a P Starbucks Frappucino.

  11. Reduction of Erosive Wear in situ by Stannous Fluoride-Containing Toothpaste.

    NARCIS (Netherlands)

    Huysmans, M.C.D.N.J.M.; Jager, D.H.; Ruben, J.L.; Unk, D.E.; Klijn, C.P.; Vieira, A.M.

    2011-01-01

    Background/Aims: Stannous fluoride (SnF) has been suggested as a dental erosion-preventive agent. The aim of this single-centre, randomized, double-blind, in situ study was to evaluate the effect of toothpastes with SnF in the prevention of erosive enamel wear. Methods: A combined split-mouth

  12. Are sugar-free confections really beneficial for dental health?

    Science.gov (United States)

    Nadimi, H; Wesamaa, H; Janket, S-J; Bollu, P; Meurman, J H

    2011-10-07

    Various sugar substitutes have been introduced and are widely used in confections and beverages to avoid tooth decay from sugar and other fermentable carbohydrates. One group of sugar substitutes are sugar alcohols or polyols. They have been specifically used in foods for diabetic patients because polyols are not readily absorbed in the intestine and blood stream, preventing post-prandial elevation of glucose level. Additionally they may lower caloric intake. We searched PubMed, Cochrane Controlled Trials Registry, Cochrane Oral Health Review, Centre for Reviews and Dissemination in the UK, National Library for Public Health and a Centre for Evidence Based Dentistry website up to the end of October 2010, using the search terms 'sugar alcohol' or 'sugar-free' or 'polyols' and combined with a search with terms 'dental caries' or 'dental erosion'. Xylitol, a polyol, has been approved by the US Food and Drug Administration for its non-cariogenic properties that actually reduce the risk of dental decay and recently, the European Union also officially approved a health claim about xylitol as a 'tooth friendly' component in chewing gums. Although the presence of acidic flavourings and preservatives in sugar-free products has received less attention, these additives may have adverse dental health effects, such as dental erosion. Furthermore, the term sugar-free may generate false security because people may automatically believe that sugar-free products are safe on teeth. We concluded that polyol-based sugar-free products may decrease dental caries incidence but they may bring another dental health risk, dental erosion, if they contain acidic flavouring. There is a need for properly conducted clinical studies in this area.

  13. Erosion-inhibiting effect of sodium fluoride and titanium tetrafluoride treatment in vitro

    NARCIS (Netherlands)

    Rijkom, Hans van; Ruben, J.; Vieira, A.; Huysmans, M.C.; Truin, G-J.; Mulder, J.

    2003-01-01

    The prevention of dental erosion with fluoride is still largely unknown territory. It was the aim of this study to determine the erosion-inhibiting effect of topical neutral 1% sodium fluoride (NaF) application and an application of a 4% titanium tetrafluoride (TiF4) solution compared with no

  14. Management of periodontal destruction caused by overhanging dental restoration

    Directory of Open Access Journals (Sweden)

    Misnova Misnova

    2016-06-01

    Full Text Available Periodontal tissue inflammations are occasionally caused by positions of restoration margins, particularly if they are placed subgingivally. A 44-year old male was referred to the Dental and Mouth Hospital of Dentistry Faculty Hasanuddin University with the chief complaint of severe pain at right posterior maxillary. Clinical examinations demonstrate a 7-mm periodontal pocket at buccal aspect of 16 teeth with tooth mobility °2. Overhanging dental composite restorations of Class V were detected at the subgingival areas of 15, 16, and 17. Radiographic results show vertically and horizontally alveolar bone loss. This case report is aimed to describe the management of periodontal tissue destruction as a result of overhanging dental composite restorations. Scaling and root planing were conducted as the initial therapy. The periodontal surgery was performed a week after the initial therapy. A full-thickness flap design with sulcular incision from 14 to 18 was made before the pocket curretage and necrotic tissue debridement along with restoration recontouring. The flap was sutured with simple suture technique. Periodontal dressing was packed for a week. Antibiotics, analgetics and antiinflammatory drugs were prescribed per orally. There was no history of pain a week after the surgical procedure. Tooth mobility was decreased to °1 and the periodontal pocket was reduced to 3 mm. Overhanging dental restorations may lead to periodontal tissue destruction. The subgingivally placement of those restorations should consider the health of periodontal tissues.

  15. New techniques in dental surgical CT

    International Nuclear Information System (INIS)

    Rabin, D.N.; Rabin, H.; Sakowicz, B.A.; Rabin, M.A.; Rabin, S.I.; Schwartz, A.

    1991-01-01

    This paper demonstrates how CT can be used with dental software to evaluate prosthetic failure and for planning dental implants when a stent is used. The Food and Drug Administration issued a safety alert for proplast-coated temporomandibular joint prostheses. Prosthetic failure occurs with migration, fragmentation, or bone erosion. Sagittal CT requiring a special head holder can instead be performed with reformatted sagittal images. The technique of dental implant CT changes when a dental stent is used to provide more accurate implant anchorage and planning. Images must be parallel to the occlusal plane. We will demonstrate these techniques and present their rationale

  16. [Helicobacter pylori in the development of dental caries].

    Science.gov (United States)

    Moseeva, M V; Belova, E V; Vakhrushev, Ia M

    2010-01-01

    It is shown, that in patients with erosive and ulcer defects of gastroduodenal zone at settling Helicobacter pylori (Hp) in an oral cavity in 100% of cases caries develops at intensity 13.6 +/- 1.4 teeth. Produced Hp protease and ammonia cause disintegration connected to protein silica acids and reduce activity lysocim, worsening, thus, fluid and protective properties of a saliva. In the subsequent infringement of autopurification of a teeth results in accumulation of a dental strike where protease activity conditionally pathogenic microflora conducts to depolymerization and demineralization enamels of a teeth.

  17. Modeling the fluid/soil interface erosion in the Hole Erosion Test

    Directory of Open Access Journals (Sweden)

    Kissi B.

    2012-07-01

    Full Text Available Soil erosion is a complex phenomenon which yields at its final stage to insidious fluid leakages under the hydraulic infrastructures known as piping and which are the main cause of their rupture. The Hole Erosion Test is commonly used to quantify the rate of piping erosion. In this work, The Hole Erosion Test is modelled by using Fluent software package. The aim is to predict the erosion rate of soil during the hole erosion test. The renormalization group theory – based k–ε turbulence model equations are used. This modelling makes it possible describing the effect of the clay concentration in flowing water on erosion. Unlike the usual one dimensional models, the proposed modelling shows that erosion is not uniform erosion along the hole length. In particular, the concentration of clay is found to increase noticeably the erosion rate.

  18. Protection of enamel surfaces in the oral cavity

    DEFF Research Database (Denmark)

    Lazovic, Maja Bruvo

    The two main diseases that can affect the tooth enamel are dental caries and dental erosion, which both are caused by exposure of the enamel surfaces to acids. In the case of dental caries, acids from bacterial metabolism cause chemical dissolution of the tooth surface, whereas acids from drinks...... and foodstuffs or gastric juice can cause dental erosion. During a lifetime the enamel surface is also exposed to fluids that can have protective effects against dental caries and erosion such as saliva, various foodstuffs, drinking water and many types of drinks. However, little is still known about simple...... inorganic interactions between different fluids and dental caries and little is also known about which saliva proteins are able to protect the enamel surface against dental erosion. Therefore, the overall aim of this thesis was to examine simple inorganic and protein related protective effects with dental...

  19. Causes of degradation and erosion of a blanket mire in the southern Pennines, UK

    NARCIS (Netherlands)

    Yeloff, D.; Hunt, C.O.; Labadz, J.C.

    2006-01-01

    This study investigates the causes of erosion and degradation of March Haigh, a blanket mire in the southern Pennines (UK), over a period of 160 years starting in 1840 AD. Peat samples taken from the site were dated using 210Pb; their humification and magnetic susceptibility were measured; and they

  20. Erosion corrosion in water-steam systems: Causes and countermeasures

    International Nuclear Information System (INIS)

    Heitmann, H.G.; Kastner, W.

    1985-01-01

    For the purpose of a better understanding of erosion corrosion, the physical and chemical principles will be summarized briefly. Then results obtained at KWU in the BENSON test section in tests on test specimens in single-phase flow of fully demineralized water will be presented. The experimental studies provide information about the most important influencing parameters. These include flow rate, fluid temperature and water quality (pH value and oxygen content). In addition, the resistance of various materials is compared, and the resistance of magnetite coatings to erosion corrosion is investigated. Furthermore, tests are presented that will show the extent to which erosion corrosion in power plants can be influenced by chemical measures

  1. Dental and oropharyngeal lesions in rats with chronic acid reflux esophagitis.

    Science.gov (United States)

    Shimazu, Rintaro; Yamamoto, Mihoko; Minesaki, Akimichi; Kuratomi, Yuichiro

    2018-06-01

    In this study, we evaluated pathological changes in the tooth and pharynx of GERD rats to elucidate the association between gastric acid reflux and oral and pharyngeal diseases. An experimental rat model of chronic acid reflux esophagitis was surgically created. The oral cavities were observed histologically every 2 weeks until 20 weeks after surgery. At 10 weeks after surgery, molar crown heights in GERD rats were shorter than that in control rats, and inflammatory cell infiltration by gastric acid reflux was found in the periodontal mucosa of GERD rats. Furthermore, dental erosion progressed in GERD rats at 20 weeks after surgery, and enamel erosion and dentin exposure were observed. During the same period, inflammatory cell infiltration was observed in the mucosa of the posterior part of the tongue. These findings suggest that gastric acid reflux may be one of the exacerbating factors of dental erosion, periodontitis and glossitis. We investigated oral changes in an experimental rat model of GERD and observed development of dental erosion, periodontitis and glossitis. Our findings suggested chronic gastric acid reflux may be involved in the pathogenesis of oral disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Interactions between dodecyl phosphates and hydroxyapatite or tooth enamel: relevance to inhibition of dental erosion.

    Science.gov (United States)

    Jones, Siân B; Barbour, Michele E; Shellis, R Peter; Rees, Gareth D

    2014-05-01

    Tooth surface modification is a potential method of preventing dental erosion, a form of excessive tooth wear facilitated by softening of tooth surfaces through the direct action of acids, mainly of dietary origin. We have previously shown that dodecyl phosphates (DPs) effectively inhibit dissolution of native surfaces of hydroxyapatite (the type mineral for dental enamel) and show good substantivity. However, adsorbed saliva also inhibits dissolution and DPs did not augment this effect, which suggests that DPs and saliva interact at the hydroxyapatite surface. In the present study the adsorption and desorption of potassium and sodium dodecyl phosphates or sodium dodecyl sulphate (SDS) to hydroxyapatite and human tooth enamel powder, both native and pre-treated with saliva, were studied by high performance liquid chromatography-mass Spectrometry. Thermo gravimetric analysis was used to analyse residual saliva and surfactant on the substrates. Both DPs showed a higher affinity than SDS for both hydroxyapatite and enamel, and little DP was desorbed by washing with water. SDS was readily desorbed from hydroxyapatite, suggesting that the phosphate head group is essential for strong binding to this substrate. However, SDS was not desorbed from enamel, so that this substrate has surface properties different from those of hydroxyapatite. The presence of a salivary coating had little or no effect on adsorption of the DPs, but treatment with DPs partly desorbed saliva; this could account for the failure of DPs to increase the dissolution inhibition due to adsorbed saliva. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Frequency of Application of AmF/NaF/SnCl2 Solution and Its Potential in Inhibiting the Progression of Erosion in Human Dental Enamel - An In Vitro Study.

    Science.gov (United States)

    da Silva, Camilla Vieira; Nazello, Jessica Laporta; de Freitas, Patricia Moreira

    To evaluate whether increasing the frequency of its use can enhance the protective effect of AmF/NaF/SnCl2 solution against dental erosion. Sixty human enamel samples were obtained from sound human third molars, and after the formation of incipient erosive lesions (1% citric acid, pH 4.0, for 3 min), they were divided into five treatment groups (n = 12): G1 - deionised water (negative control); G2 - NaF solution (positive control) once a day; G3 - NaF solution (positive control) twice a day; G4 - AmF/NaF/SnCl2 solution once a day; G5 - AmF/NaF/SnCl2 solution twice a day. The samples were then subjected to 5 days of erosive cycling through 6 daily immersions (2 min each) in citric acid solution (0.05 M, pH 2.6). At the end of erosive cycling, surface wear was determined by means of optical profilometry. One-way ANOVA showed that the surface wear was affected by surface treatments (p enamel surface loss and its use twice a day potentiated its anti-erosive effect.

  4. Predicting of soil erosion with regarding to rainfall erosivity and soil erodibility

    Science.gov (United States)

    Suif, Zuliziana; Razak, Mohd Amirun Anis Ab; Ahmad, Nordila

    2018-02-01

    The soil along the hill and slope are wearing away due to erosion and it can take place due to occurrence of weak and heavy rainfall. The aim of this study is to predict the soil erosion degree in Universiti Pertahanan Nasional Malaysia (UPNM) area focused on two major factor which is soil erodibility and rainfall erosivity. Soil erodibility is the possibilities of soil to detach and carried away during rainfall and runoff. The "ROM" scale was used in this study to determine the degree of soil erodibility, namely low, moderate, high, and very high. As for rainfall erosivity, the erosive power caused by rainfall that cause soil loss. A daily rainfall data collected from January to April was analyzed by using ROSE index classification to identify the potential risk of soil erosion. The result shows that the soil erodibilty are moderate at MTD`s hill, high at behind of block Lestari and Landslide MTD hill, and critical at behind the mess cadet. While, the highest rainfall erosivity was recorded in March and April. Overall, this study would benefit the organization greatly in saving cost in landslide protection as relevant authorities can take early measures repairing the most affected area of soil erosion.

  5. In Situ analysis of CO2 laser irradiation on controlling progression of erosive lesions on dental enamel.

    Science.gov (United States)

    Lepri, Taísa Penazzo; Scatolin, Renata Siqueira; Colucci, Vivian; De Alexandria, Adílis Kalina; Maia, Lucianne Cople; Turssi, Cecília Pedroso; Corona, Silmara Aparecida Milori

    2014-08-01

    The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty-six slabs of bovine incisors enamel (5 × 3 × 2.5 mm(3) ) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH = 2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (λ = 10.6 µm; 0.5 W) and nonirradiate. After a 2-day lead-in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross-over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three-way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P = 0.419). Erosive challenge significantly increased enamel wear (P = 0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2 -laser irradiated and non-irradiated (P = 0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid. © 2014 Wiley Periodicals, Inc.

  6. MALIGNANT TRANSFORMATION OF EROSIVE ORAL LICHEN PLANUS

    Directory of Open Access Journals (Sweden)

    Siti Chumaeroh

    2006-04-01

    Full Text Available Lichen planus is a relatively common inflammatory disorder which may have cutaneous and or mucosal manifestation. The malignant potential of oral lichen planus is still debatable. Some authors are sceptical about the premalignant nature of the disease, while other investigators have reported that malignant transformations occur in 1-10% of the cases. The aim of this study is to report a case of erosive lichen plans which shows malignant transformation of histopathologic examination. A man of 39 years old visited the Dental Department or Kajradi's Hospital with pain symptoms of the palate, buccal and gingival mucosa on both sides for 6 months. The physical examination shows the white lesion with striae configuration and pain, red erosive area inside the palate extends to the buccal mucosa and the gingival mucosa. The suspect diagnosis is erosive lichen planus, but the histopathologic examination shows epidermoid carcinoma. It is concluded that erosive oral lichen planus has the potential to transform into epidermoid carcinoma.

  7. Comparative investigation of smooth polycrystalline diamond films on dental burs by chemical vapor deposition

    Science.gov (United States)

    Sein, Htet; Ahmed, Waqar; Rego, Christopher; Jackson, Mark; Polini, Riccardo

    2006-04-01

    Depositions of hot filament chemical vapor-deposited diamond on cobalt-cemented tungsten carbide (WC-Co) rotary cutting dental burs are presented. Conventional dental tools made of sintered polycrystalline diamond have a number of problems associated with the heterogeneity of the crystallite, decreased cutting efficiency, and short life. A preferential (111) faceted diamond was obtained after 15 h of deposition at a growth rate of 1.1 µm/h. Diamond-coated WC-Co dental burs and conventional sintered burs are mainly used in turning, milling, and drilling operations for machining metal ceramic hard alloys such as CoCr, composite teeth, and aluminum alloy in the dental laboratory. The influence of structure, the mechanical characteristics of both diamond grains and hard alloys on the wear behavior, as well as the regimen of grinding on diamond wear are considered. Erosion wear properties are also investigated under air-sand erosion testing. After machining with excessive cutting performance, calculations can be made on flank and crater wear areas. Diamond-coated WC-Co dental burs offered significantly better erosion and wear resistance compared with uncoated WC-Co tools and sintered burs.

  8. Erosive gastritis

    International Nuclear Information System (INIS)

    Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

    1982-01-01

    Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported. (orig.)

  9. Erosive gastritis

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

    1982-08-01

    Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported.

  10. Instrument of self-perception and knowledge of dental erosion: cross-cultural adaptation to the Brazilian population

    Directory of Open Access Journals (Sweden)

    Sandro Bertazzo SILVA

    2015-01-01

    Full Text Available There are few instruments available in Brazil for obtaining data on dental erosion among adults. For this reason, the interview entitled “A Survey on Hong Kong People’s Dietary Behavior in Relations to Acid Erosion”, published in English, was considered for translation. The aim of this study was to perform a cross-cultural adaptation and content validation for the Brazilian population. After obtaining the author’s permission, the interview underwent several stages: translation, back translation, review by a bilingual person and a committee of experts, administration of the English instrument and of the Portuguese version to a bilingual group, and pretesting in a convenience sample of 50 adults. The interview was translated and adapted to the Portuguese language and the Brazilian culture. The analysis of the data revealed that the interview was easy to apply, conduct and understand; therefore, it was considered viable and capable of being used in different studies.

  11. Effects of erosive, cariogenic or combined erosive/cariogenic challenges on human enamel: an in situ/ex vivo study.

    Science.gov (United States)

    Honório, H M; Rios, D; Santos, C F; Magalhães, A C; Buzalaf, M A R; Machado, M A A M

    2008-01-01

    Individuals with cariogenic diet can also consume erosive beverages. Thus, it seems necessary to investigate a possible caries/erosion interaction. To test in situ/ex vivo a combination of these challenges, 11 subjects wore intraoral appliances containing four enamel blocks randomly assigned. In the first 2-week phase, the appliances were immersed in a cola drink 3 times/day. Two blocks were free of plaque (erosion only: EO) and two blocks were covered with plaque (erosion + plaque: EP). In the second 2-week phase, four new blocks were all covered with plaque and subjected to a sucrose solution 8 times/day. Among the four new blocks, two were also subjected to the cola drink 3 times/day (erosion + caries: EC) while the other two were not (caries only: CO). Thus, in EO, the specimens were fixed at the intraoral appliance level. In EP, EC and CO they were fixed 1.0 mm under the appliance level and covered with plastic meshes for dental plaque accumulation. Changes in wear and hardness were measured. Data were tested using ANOVA and Tukey's test (p cariogenic challenges showed less enamel alterations when compared to erosive or cariogenic challenges only. (c) 2008 S. Karger AG, Basel.

  12. EATING DISORDERS: DENTAL IMPLICATIONS – CASE REPORT

    Directory of Open Access Journals (Sweden)

    Matjaž Rode

    2003-10-01

    Full Text Available Background. Obesity, anorexia and bulimia are typical civilisation diseases or diseases of unhealthy living. They affect mainly white women in their childhood and adolescence. Occurrence of these diseases is getting higher also in Slovenia. Changes inside the oral cavity of a bulimic patient may be detected during a routine clinical examination. This places dental professionals in a position to be among the first to detect bulimia which is usually characterized by episodes of purging behaviors such as self-induced vomiting. Such vomiting brings stomach acids in contact with the mouth and teeth, causing erosion of tooth enamel which often leads to severely decayed teeth.Methods. This study presents a case of successful treatment of oral symptoms and dental rehabilitation in female patient with bulimia.Conclusions. Dental rehabilitation for bulimic patients is more than just a substituting of their bad and lost teeth. It is actually the first step toward their regained self-respect. Therefore it is important for the dentist to be familiar with the clinical symptoms of these diseases that can be revealed in oral cavity to efficiently contribute to a patient rehabilitation.

  13. Unusual Presentation of Hydatidosis - Neck Lump Causing Costo-Vertebral Erosion.

    Science.gov (United States)

    Alam, Mehtab; Hasan, Syed-Abrar; Hashmi, Shahab-Farkhund

    2016-09-01

    Hydatid disease caused by larval stage of Echinococcus has been recognized endemically in many countries. Liver and lungs are the most commonly affected organs. Involvement of the head and neck region is rare and bony erosion due to hydatidosis is even rarer. We report a case of a 17-year-old girl from a poor socio-economic background who presented with a right sided supraclavicular lump, which after surgical excision and histopathological examination was diagnosed as hydatid cyst of neck. Because of its rarity in the neck region, primary diagnosis of hydatid cyst is overlooked and usually not included in the differential diagnosis of cystic neck swellings. A high index of suspicion is necessary to diagnose hydatid disease in an unusual location even in endemic areas.

  14. The Problem of Soil Erosion in Developing Countries--Direct and Indirect Causes and Recommendations for Reducing It to a Sustainable Level.

    Science.gov (United States)

    Middlebrook, Cathy H.; Goode, Pamela M.

    1992-01-01

    Presents direct and indirect causes of erosion in developing countries. Identifies soil conservation developments ranging from major international policy reforms to small-scale, local farming programs. Suggests that strategies at all levels, and the political will to implement them, are needed if erosion is to be reduced to a sustainable rate. (23…

  15. The influence of rill density on soil erosion against USLE-soil erosion methode

    OpenAIRE

    Rizalihadi, A.M.; Faimah, B.E.; Nazia, C.L.

    2013-01-01

    Land and water is one of the major natural resource which has an important role for human life. Exploitation of land in catchment areas that not correspond to its carrying capacity will cause damage. One of the effect is increassing the soil erosion. Continuous erosion will also lead to increased sediment transport in rivers that disrupt the ship navigation on estuary due sediment accumulation. At present, soil erosion is estimated using USLE method, which is only limited to the erosion in th...

  16. Noninvasive restoration of severe erosion by means of CAD/CAM indirect composite occlusal restorations : a technical note

    NARCIS (Netherlands)

    Schepke, Ulf; Cune, Marco S.

    2014-01-01

    The use of new materials and computer-aided design/computer-aided manufacturing techniques can help dental practitioners efficiently treat dental erosion in a predictable manner. If the vertical dimension of occlusion has to be increased, the static and dynamic occlusion need to be reorganized. This

  17. Understanding Soil Erosion in Irrigated Agriculture

    OpenAIRE

    O' Schwankl, Lawrence J

    2006-01-01

    A soil's physical and chemical properties determine whether it is vulnerable to erosion, which can reduce soil quality and cause other problems besides. Learn the basics of identifying what type of erosion is affecting your land and what's causing it.

  18. [Nutrition, diet and dental health--de- and remineralisation of teeth].

    Science.gov (United States)

    Imfeld, Thomas

    2008-02-01

    There is little if any evidence that nutrition during the time of tooth formation has any clinically significant effect on caries susceptibility of erupted teeth in man. Caries, erosion and demastication are not nutritional diseases. They are, however, diet-related diseases because erupted teeth are subject to local chemical and mechanical effects of the diet contacting the teeth. Caries is the result of a chronic undermining demineralisation of the teeth by organic acids that are produced by the bacteria of the dental biofilm while fermenting carbohydrates from the human diet. Dental erosion is the result of a chronic localised loss of dental hard tissue etched away from the surface by acids derived from the diet or from gastric reflux. The physicochemical grounds of de- and remineralisation of teeth are explained using detailed diagrams. Initial caries lesions without cavitation of the surface can remineralise (heal) under conditions of low cariogenic diet and good oral hygiene. However, once the surface has broken and cavitation occurred, there is no alternative to restorative dental therapy because remineralisation is no more possible.

  19. Effect of pretreatment with an Er:YAG laser and fluoride on the prevention of dental enamel erosion.

    Science.gov (United States)

    dos Reis Derceli, Juliana; Faraoni-Romano, Juliana Jendiroba; Azevedo, Danielle Torres; Wang, Linda; Bataglion, César; Palma-Dibb, Regina Guenka

    2015-02-01

    The aim of this study was to evaluate the effect of the Er:YAG laser and its association with fluoride (1.23% acidulate phosphate fluoride gel) on the prevention of enamel erosion. Sixty specimens were obtained from bovine enamel (4 × 4 mm), which were ground flat, polished, and randomly divided into five groups according to the preventive treatments: control-fluoride application; L--Er:YAG laser; L+F--laser + fluoride; F+L--fluoride + laser; L/F--laser/fluoride simultaneously. Half of the enamel surface was covered with nail varnish (control area), and the other half was pretreated with one of the preventive strategies to subsequently be submitted to erosive challenge. When the laser was applied, it was irradiated for 10 s with a focal length of 4 mm and 60 mJ/2 Hz. Fluoride gel was applied for 4 min. Each specimen was individually exposed to regular Coca-Cola® for 1 min, four times/day, for 5 days. Wear analysis was performed with a profilometer, and demineralization was assessed with an optical microscope. Data were analyzed using the Kruskal-Wallis test (wear)/Dunn test and ANOVA/Fisher's exact tests. The group L/F was similar to control group. The other groups showed higher wear, which did not present differences among them. In the demineralization assessment, the groups F+L and L/F showed lower demineralization in relation to the other groups. It can be concluded that none preventive method was able to inhibit dental wear. The treatments L/F and F+L showed lower enamel demineralization.

  20. Effect of carbonated beverages, coffee, sports and high energy drinks, and bottled water on the in vitro erosion characteristics of dental enamel.

    Science.gov (United States)

    Kitchens, Michael; Owens, Barry M

    2007-01-01

    This study evaluated the effect of carbonated and non-carbonated beverages, bottled and tap water, on the erosive potential of dental enamel with and without fluoride varnish protection. Beverages used in this study included: Coca Cola Classic, Diet Coke, Gatorade sports drink, Red Bull high-energy drink, Starbucks Frappuccino coffee drink, Dasani water (bottled), and tap water (control). Enamel surfaces were coated with Cavity Shield 5% sodium fluoride treatment varnish. Twenty-eight previously extracted human posterior teeth free of hypocalcification and caries were used in this study. The coronal portion of each tooth was removed and then sectioned transverse from the buccal to lingual surface using a diamond coated saw blade. The crown sections were embedded in acrylic resin blocks leaving the enamel surfaces exposed. The enamel surfaces were polished using 600 to 2000 grit abrasive paper and diamond paste. Test specimens were randomly distributed to seven beverage groups and comprised 4 specimens per group. Two specimens per beverage group were treated with a fluoride varnish while 2 specimens did not receive fluoride coating. Surface roughness (profilometer) readings were performed at baseline (prior to fluoride treatment and immersion in the beverage) and again, following immersion for 14 days (24 hours/day). The test beverages were changed daily and the enamel specimens were immersed at 37 degrees C. Surface roughness data was evaluated using multiple factor ANOVA at a significance level of pStarBucks coffee, Dasani water, and tap water. Fluoride varnish was not a significant impact factor; however, beverage (type) and exposure time were significant impact variables. Both carbonated and non-carbonated beverages displayed a significant erosive effect on dental enamel; however, fluoride varnish treatments did not demonstrate a significant protective influence on enamel surfaces.

  1. Analysis of the causes of dental implant fracture: A retrospective clinical study.

    Science.gov (United States)

    Stoichkov, Biser; Kirov, Dimitar

    2018-01-01

    Fracture of osseointegrated dental implants is the most severe mechanical complication. The aim of the present study was to analyze possible causative factors for implant body fracture. One hundred and one patients with 218 fitted implants and a follow-up period of 3 to 10 years were studied. Factors associated with biomechanical and physiologic overloading such as parafunctional activity (eg, bruxism), occlusion, and cantilevers, and factors related to the planning of the dental prosthesis, available bone volume, implant area, implant diameter, number of implants, and their inclination were tracked. The impact of their effect was analyzed using the Bonferroni-corrected post-hoc Mann-Whitney test for each group. The incidence of dental implant fracture was 2.3% in the investigated cases. Improper treatment planning, bruxism, and time of the complication setting in were the main factors leading to this complication. Typical size effect was established only for available bruxism, occlusal errors, and their activity duration. These complications were observed most often with single crown prostheses, and in combination with parafunctional activities such as bruxism and lack of implant-protected occlusion. Occlusal overload due to bruxism or inappropriate or inadequate occlusion as a single factor or a combination of these factors during the first years after the functional load can cause implant fracture. Fracture of the implant body more frequently occurred with single crowns than with other implant-supported fixed dental prostheses.

  2. Erosion of enamel by non-carbonated soft drinks with and without toothbrushing abrasion.

    Science.gov (United States)

    Hemingway, C A; Parker, D M; Addy, M; Barbour, M E

    2006-10-07

    To investigate how enamel loss due to erosion, and due to cycling of erosion and abrasion, depends on compositional parameters of soft drinks, and particularly whether the thickness of the erosive softened layer is a function of drink composition. University dental hospital research laboratory in the UK, 2004. Six drinks were chosen based on their popularity and composition: apple juice, orange juice, apple drink, orange drink, cranberry drink and 'ToothKind' blackcurrant drink. Group A samples (n = 36) were exposed to soft drinks at 36 degrees C for six consecutive 10 minute periods. Group B samples (n = 36) were subjected to alternating erosion and toothbrushing, repeated six times. Enamel loss was measured using optical profilometry. Group A: significant enamel loss was seen for all drinks (p composition of the erosive medium.

  3. Gastroesophageal Reflux Disease and Tooth Erosion

    Directory of Open Access Journals (Sweden)

    Sarbin Ranjitkar

    2012-01-01

    Full Text Available The increasing prevalence of gastroesophageal reflux disease (GERD in children and adults, and of “silent refluxers” in particular, increases the responsibility of dentists to be alert to this potentially severe condition when observing unexplained instances of tooth erosion. Although gastroesophageal reflux is a normal physiologic occurrence, excessive gastric and duodenal regurgitation combined with a decrease in normal protective mechanisms, including an adequate production of saliva, may result in many esophageal and extraesophageal adverse conditions. Sleep-related GERD is particularly insidious as the supine position enhances the proximal migration of gastric contents, and normal saliva production is much reduced. Gastric acid will displace saliva easily from tooth surfaces, and proteolytic pepsin will remove protective dental pellicle. Though increasing evidence of associations between GERD and tooth erosion has been shown in both animal and human studies, relatively few clinical studies have been carried out under controlled trial conditions. Suspicion of an endogenous source of acid being associated with observed tooth erosion requires medical referral and management of the patient as the primary method for its prevention and control.

  4. Prevalence of dental fear and its causes using three measurement scales among children in New Delhi.

    Science.gov (United States)

    Rajwar, Anju Singh; Goswami, Mridula

    2017-01-01

    There is a great need for identifying fearful children, who often present problems in patient management, thus affecting the quality of dental care rendered to them. This study is unique in the way that dental fear was assessed through three fear scales as research has suggested the use of more than one scale because each scale has its own restrictions and is open to criticism. The aim of this study was to evaluate dental fear and anxiety (DFA) among children aged 3-14 years using three fear measurement scales. The study was conducted on children (3-14 years) who visited the Department of Pedodontics and Preventive Dentistry at Maulana Azad Institute of Dental Sciences, New Delhi. The DFA levels were measured using three fear measurement scales, i.e., facial image scale (FIS), dental fear scale (DFS), and children's fear survey schedule-dental subscale (CFSS-DS). The dental behavior was estimated using the Frankl's behavior rating scale (FBRS). The prevalence of dental fear according to FIS was 14.3%, according to DFS was 22.6%, and according to CFSS-DS was 7.4%. In assessment of the behavior of children in the clinics through FBRS, it was observed that he maximum number of respondents (69.8%) showed Frankl's Rating 3 i.e. positive. In the DFS and CFSS-DS, the factor which caused most fear was "feeling the needle injected" and "injections," respectively. Assessment of dental fear is an extremely useful tool for the dental practitioner, who can use it to customize the behavioral treatment and management for child patients.

  5. Prevalencia de erosión dental en niños de 6 a 12 años de edad utilizando el índice Basic Erosive Wear Examination (BEWE

    Directory of Open Access Journals (Sweden)

    Karla Rosella Baltuano Songhurst

    2016-01-01

    Full Text Available Objetivos: El objetivo de este estudio fue determinar la prevalencia, distribución y severidad de erosión dental en niños de 6 a 12 años de edad de la institución educativa pública Domingo Faustino Sarmiento, Lima-Perú. Material y métodos: Una muestra aleatoria de 247 niños de primaria fueron evaluados clínicamente para medir la erosión dental utilizando el índice Basic Erosive Wear Examination (BEWE, obteniendo un score acumulativo el cual posteriormente es comparado con el cuadro de niveles de riesgo/manejo clínico propio del índice. Se realizó un análisis descriptivo de las variables presencia de erosión dental, género, edad, localización de la lesión. Resultados: La prevalencia de erosión dental fue de 9.31% y la media y DS del score BEWE fue 0.25±0.90. Conclusiones: La erosión dental en niños de 6 a 12 años encontrada en esta institución educativa es menor a la de otros estudios epidemiológicos realizados en escuelas de otras partes del mundo. Este tipo de estudio epidemiológico puede ser viable en niños de este rango de edad de otras partes del Perú, en donde las costumbres, hábitos alimenticios y otros factores varían notablemente.

  6. Prevalence of dental fear and its causes using three measurement scales among children in New Delhi

    Directory of Open Access Journals (Sweden)

    Anju Singh Rajwar

    2017-01-01

    Full Text Available Introduction: There is a great need for identifying fearful children, who often present problems in patient management, thus affecting the quality of dental care rendered to them. This study is unique in the way that dental fear was assessed through three fear scales as research has suggested the use of more than one scale because each scale has its own restrictions and is open to criticism. Aim: The aim of this study was to evaluate dental fear and anxiety (DFA among children aged 3–14 years using three fear measurement scales. Methods: The study was conducted on children (3–14 years who visited the Department of Pedodontics and Preventive Dentistry at Maulana Azad Institute of Dental Sciences, New Delhi. The DFA levels were measured using three fear measurement scales, i.e., facial image scale (FIS, dental fear scale (DFS, and children's fear survey schedule-dental subscale (CFSS-DS. The dental behavior was estimated using the Frankl's behavior rating scale (FBRS. Results: The prevalence of dental fear according to FIS was 14.3%, according to DFS was 22.6%, and according to CFSS-DS was 7.4%. In assessment of the behavior of children in the clinics through FBRS, it was observed that he maximum number of respondents (69.8% showed Frankl's Rating 3 i.e. positive. In the DFS and CFSS-DS, the factor which caused most fear was “feeling the needle injected” and “injections,” respectively. Conclusion: Assessment of dental fear is an extremely useful tool for the dental practitioner, who can use it to customize the behavioral treatment and management for child patients.

  7. Erosion and erosion-corrosion

    International Nuclear Information System (INIS)

    Isomoto, Yoshinori

    2008-01-01

    It is very difficult to interpret the technical term of erosion-corrosion' which is sometimes encountered in piping systems of power plants, because of complicated mechanisms and several confusing definitions of erosion-corrosion phenomena. 'FAC (flow accelerated corrosion)' is recently introduced as wall thinning of materials in power plant systems, as a representative of 'erosion-corrosion'. FAC is, however, not necessarily well understood and compared with erosion-corrosion. This paper describes firstly the origin, definition and fundamental understandings of erosion and erosion-corrosion, in order to reconsider and reconfirm the phenomena of erosion, erosion-corrosion and FAC. Next, typical mapping of erosion, corrosion, erosion-corrosion and FAC are introduced in flow velocity and environmental corrosiveness axes. The concept of damage rate in erosion-corrosion is finally discussed, connecting dissolution rate, mass transfer of metal ions in a metal oxide film and film growth. (author)

  8. The Major Cause of Observed Erosion Surge on the Beaches North ...

    African Journals Online (AJOL)

    Surges in coastal erosion north of Dar es Salaam city have been documented from 1977 to the early 1980s and around 1997/98. Analysis of the wind data shows that the documented increase in coastal erosion coincided with increased wind speeds. Extreme winds in excess of 10-11 m s-1 were experienced during ...

  9. Dental pathology in dolphins (Cetacea: Delphinidae) from the southern coast of Brazil.

    Science.gov (United States)

    Loch, Carolina; Grando, Liliane J; Kieser, Jules A; Simões-Lopes, Paulo C

    2011-05-09

    Pathological processes observed in the stomatognathic systems of mammalian species are a useful source of information about the habits, evolution and general health of such animals. Studies of pathological conditions on teeth are common in humans and other primates, but rare in wild animals in general and marine mammals in particular. For cetaceans, previous studies provided scanty records of dental anomalies in a few species. This is the first broad and systematic inventory of dental pathology in dolphins. Specimens stored at scientific collections from the southern coast of Brazil were visually inspected under a stereoscopic microscope using a dental explorer. Diagnosis of lesions and anomalies followed literature descriptions. Abnormalities such as caries-like lesions, mineralized calculus deposits, dental erosion, enamel anomalies (hypoplasia and exogenous pigmentation), root resorption, germination and other shape anomalies, were diagnosed in the delphinids Sotalia guianensis, Delphinus capensis, Stenella frontalis, Stenella coeruleoalba, Lagenodelphis hosei, Pseudorca crassidens, Orcinus orca, Steno bredanensis and Tursiops truncatus. Endogenous causes may be related to the occurrence of certain conditions, but the aetiology of caries-like lesions and calculus accumulation is still unknown for cetaceans. The diagnosis of alveolar anomalies and other bone lesions in specimens with dental pathology lead us to believe these lesions modify the integrity of the periodontal ligament and bony tissues, adding to the burden of morbidity of affected animals.

  10. Caries and dental erosion: are Soroti children and adolescents at ...

    African Journals Online (AJOL)

    Department of Pediatric Dentistry, British Columbia Children's Hospital, Canada. All authors have ... trend of lower erosion scores was seen in children compared to adolescents. Greater frequency of .... marketing efforts by major soft-drink companies. Nev- ertheless ... liability of a food frequency questionnaire. Community.

  11. Numerical study of impact erosion of multiple solid particle

    Science.gov (United States)

    Zheng, Chao; Liu, Yonghong; Chen, Cheng; Qin, Jie; Ji, Renjie; Cai, Baoping

    2017-11-01

    Material erosion caused by continuous particle impingement during hydraulic fracturing results in significant economic loss and increased production risks. The erosion process is complex and has not been clearly explained through physical experiments. To address this problem, a multiple particle model in a 3D configuration was proposed to investigate the dynamic erosion process. This approach can significantly reduce experiment costs. The numerical model considered material damping and elastic-plastic material behavior of target material. The effects of impact parameters on erosion characteristics, such as plastic deformation, contact time, and energy loss rate, were investigated. Based on comprehensive studies, the dynamic erosion mechanism and geometry evolution of eroded crater was obtained. These findings can provide a detailed erosion process of target material and insights into the material erosion caused by multiple particle impingement.

  12. Predicting the Rate of River Bank Erosion Caused by Large Wood Log

    Science.gov (United States)

    Zhang, N.; Rutherfurd, I.; Ghisalberti, M.

    2016-12-01

    When a single tree falls into a river channel, flow is deflected and accelerated between the tree roots and the bank face, increasing shear stress and scouring the bank. The scallop shaped erosion increases the diversity of the channel morphology, but also causes concern for adjacent landholders. Concern about increased bank erosion is one of the main reasons for large wood to still be removed from channels in SE Australia. Further, the hydraulic effect of many logs in the channel can reduce overall bank erosion rates. Although both phenomena have been described before, this research develops a hydraulic model that estimates their magnitude, and tests and calibrates this model with flume and field measurements, with logs with various configurations and sizes. Specifically, the model estimates the change in excess shear stress on the bank associated . The model addresses the effect of the log angle, distance from bank, and log size and flow condition by solving the mass continuity and energy conservation between the cross section at the approaching flow and contracted flow. Then, we evaluate our model against flume experiment preformed with semi-realistic log models to represent logs in different sizes and decay stages by comparing the measured and simulated velocity increase in the gap between the log and the bank. The log angle, distance from bank, and flow condition are systemically varied for each log model during the experiment. Final, the calibrated model is compared with the field data collected in anabranching channels of Murray River in SE Australia where there are abundant instream logs and regulated and consistent high flow for irrigation. Preliminary results suggest that a log can significantly increase the shear stress on the bank, especially when it positions perpendicular to the flow. The shear stress increases with the log angle in a rising curve (The log angle is the angle between log trunk and flow direction. 0o means log is parallel to flow with

  13. Estimating two indirect logging costs caused by accelerated erosion.

    Science.gov (United States)

    Glen O. Klock

    1976-01-01

    In forest areas where high soil erosion potential exists, a comparative yarding cost estimate, including the indirect costs determined by methods proposed here, shows that the total cost of using "advanced" logging methods may be less than that of "traditional" systems.

  14. Dental Erosion and Dentinal Sensitivity amongst Professional Wine Tasters in South East Queensland, Australia

    Directory of Open Access Journals (Sweden)

    Roy George

    2014-01-01

    Full Text Available Background/Aims. Professional wine tasters face a hidden occupational hazard due to the high acid content in wine. This study evaluates the self-perceived dentinal sensitivity and erosive effects of wine on the professional wine tasters of the Granite Belt and the Scenic Rim regions of South East Queensland, Australia. Methods. Seventy wineries were contacted and participants were surveyed about their professional wine tasting experience and oral health. Participants were also required to rate their tooth sensitivity prior to being examined for erosion using a modified Smith & Knight tooth wear index. The data were analysed using Mann Whitney U test and Spearman’s correlation test. Results. The results showed that most participants (25 males, 22–66 yrs, brushed twice a day; however, the majority did not floss daily and had limited knowledge of the erosive effect of wine. There was a direct correlation between years of wine tasting, age of participants, and the erosion index. Correlation was not observed between the participant’s sensitivity index and erosion index. Conclusion. The lack of significant experience of dentinal hypersensitivity amongst professional wine tasters should not prevent oral health practitioners from providing necessary counselling and undertaking preventive measures, as tooth wear can have serious long-term effect on oral health of an individual.

  15. Long-Term Analysis for Harvest Erosion Caused by Sugar Beet Production in Turkey

    Directory of Open Access Journals (Sweden)

    Selen DEVİREN SAYGIN

    2018-02-01

    Full Text Available The sustainability of soil resources is under significant threat due to the accelerated anthropogenic pressures at the historical expansion of human population. In this context, soil erosion is defined as a limiting factor for human interests in terms of ecosystem services. As an erosion type, harvest erosion occurs by harvesting of the taproot and tuberous root plants such as sugar beet (Beta vulgaris L., potato (Solanum tuberosum L., carrot (Daucus carota L. and chicory (Cichorium intybus L., has begun to take attention in recent years. The objective of this study was to estimate soil loss due to harvest erosion and to economically analyze the transport of plant nutrients between 1999 and 2016 from sugar beet growing areas in Turkey. For this aim, the compiled data of 25 different sugar factories throughout Turkey were obtained from Türkşeker and soil loss estimations were performed and economically analyzed. According to the results, average soil loss rate was calculated as 3.41 Mg ha-1y-1 for the studied period (1999-2016. That means annually an average of 716983 Mg soil removed from the Türkşeker sugar beet production areas. This result indicated that harvest erosion represents only 0.9% of soil lost by water erosion in Turkey. But, if tolerable soil loss value considered as “1 Mg ha-1 y-1”, calculated soil loss values are above this critical value for all the factories. In addition, economic assessments of soil losses showed that costs are to be more than US $10 000 annually on the 60% of the factories due to removal of plant nutrients with harvest process. And, annually US $419 433 investment must be made to recover all these losses. Conclusively, harvest erosion as an ignored erosion type must be emphasized to the economic sustainability of natural resources in fragile ecosystems such as our country.

  16. Cervical Necrotizing Fasciitis Caused by Dental Extraction

    Directory of Open Access Journals (Sweden)

    José Alcides Arruda

    2016-01-01

    Full Text Available Cervical necrotizing fasciitis is an unusual infection characterized by necrosis of the subcutaneous tissue and fascial layers. Risk factors for the development of necrotizing fasciitis include diabetes mellitus, chronic renal disease, peripheral vascular disease, malnutrition, advanced age, obesity, alcohol abuse, intravenous drug use, surgery, and ischemic ulcers. This report presents a case of necrotizing fasciitis in the cervical area caused by dental extraction in a 73-year-old woman. Cervical necrotizing fasciitis in geriatric patient is rare, and even when establishing the diagnosis and having it timely treated, the patient can suffer irreversible damage or even death. Clinical manifestations in the head and neck usually have an acute onset characterized by severe pain, swelling, redness, erythema, presence of necrotic tissue, and in severe cases obstruction of the upper airways. Therefore, the presentation of this clinical case can serve as guidance to dentists as a precaution to maintain an aseptic chain and be aware of the clinical condition of older patients and the systemic conditions that may increase the risk of infections.

  17. Effect of vegetable oils applied over acquired enamel pellicle on initial erosion

    Directory of Open Access Journals (Sweden)

    Franciny Querobim IONTA

    Full Text Available Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group: GP5 and GP100 – 5% and pure palm oil, respectively; GC5 and GC100 – 5% and pure coconut oil; GSa5 and GSa100 – 5% and pure safflower oil; GSu5 and GSu100 – 5% and pure sunflower oil; GO5 and GO100 – 5% and pure olive oil; CON− – Deionized Water (negative control and CON+ – Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control. Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf / SHf ×100]. Data were analyzed by one-way ANOVA and Tukey’s test (p0.05 and less than the other groups (p<0.05. There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.

  18. Effect of vegetable oils applied over acquired enamel pellicle on initial erosion

    Science.gov (United States)

    IONTA, Franciny Querobim; de ALENCAR, Catarina Ribeiro Barros; VAL, Poliana Pacifico; BOTEON, Ana Paula; JORDÃO, Maisa Camillo; HONÓRIO, Heitor Marques; BUZALAF, Marília Afonso Rabelo; RIOS, Daniela

    2017-01-01

    Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 – 5% and pure palm oil, respectively; GC5 and GC100 – 5% and pure coconut oil; GSa5 and GSa100 – 5% and pure safflower oil; GSu5 and GSu100 – 5% and pure sunflower oil; GO5 and GO100 – 5% and pure olive oil; CON− – Deionized Water (negative control) and CON+ – Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey’s test (p0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling. PMID:28877281

  19. Heat generation caused by ablation of dental hard tissues with an ultrashort pulse laser (USPL) system.

    Science.gov (United States)

    Braun, Andreas; Krillke, Raphael Franz; Frentzen, Matthias; Bourauel, Christoph; Stark, Helmut; Schelle, Florian

    2015-02-01

    Heat generation during the removal of dental hard tissues may lead to a temperature increase and cause painful sensations or damage dental tissues. The aim of this study was to assess heat generation in dental hard tissues following laser ablation using an ultrashort pulse laser (USPL) system. A total of 85 specimens of dental hard tissues were used, comprising 45 specimens of human dentine evaluating a thickness of 1, 2, and 3 mm (15 samples each) and 40 specimens of human enamel with a thickness of 1 and 2 mm (20 samples each). Ablation was performed with an Nd:YVO4 laser at 1,064 nm, a pulse duration of 9 ps, and a repetition rate of 500 kHz with an average output power of 6 W. Specimens were irradiated for 0.8 s. Employing a scanner system, rectangular cavities of 1-mm edge length were generated. A temperature sensor was placed at the back of the specimens, recording the temperature during the ablation process. All measurements were made employing a heat-conductive paste without any additional cooling or spray. Heat generation during laser ablation depended on the dental hard tissue (enamel or dentine) and the thickness of the respective tissue (p dental hard tissues, heat generation has to be considered. Especially during laser ablation next to pulpal tissues, painful sensations and potential thermal injury of pulp tissue might occur.

  20. The Monitoring Erosion of Agricultural Land and spatial database of erosion events

    Science.gov (United States)

    Kapicka, Jiri; Zizala, Daniel

    2013-04-01

    In 2011 originated in The Czech Republic The Monitoring Erosion of Agricultural Land as joint project of State Land Office (SLO) and Research Institute for Soil and Water Conservation (RISWC). The aim of the project is collecting and record keeping information about erosion events on agricultural land and their evaluation. The main idea is a creation of a spatial database that will be source of data and information for evaluation and modeling erosion process, for proposal of preventive measures and measures to reduce negative impacts of erosion events. A subject of monitoring is the manifestations of water erosion, wind erosion and slope deformation in which cause damaged agriculture land. A website, available on http://me.vumop.cz, is used as a tool for keeping and browsing information about monitored events. SLO employees carry out record keeping. RISWC is specialist institute in the Monitoring Erosion of Agricultural Land that performs keeping the spatial database, running the website, managing the record keeping of events, analysis the cause of origins events and statistical evaluations of keeping events and proposed measures. Records are inserted into the database using the user interface of the website which has map server as a component. Website is based on database technology PostgreSQL with superstructure PostGIS and MapServer UMN. Each record is in the database spatial localized by a drawing and it contains description information about character of event (data, situation description etc.) then there are recorded information about land cover and about grown crops. A part of database is photodocumentation which is taken in field reconnaissance which is performed within two days after notify of event. Another part of database are information about precipitations from accessible precipitation gauges. Website allows to do simple spatial analysis as are area calculation, slope calculation, percentage representation of GAEC etc.. Database structure was designed

  1. Dental biofilm infections

    DEFF Research Database (Denmark)

    Larsen, Tove; Fiehn, Nils-Erik

    2017-01-01

    and cause gingival inflammation and breakdown of supporting periodontal fibers and bone and ultimately tooth loss, i.e., gingivitis, chronic or aggressive periodontitis, and around dental implants, peri-implantitis. Furthermore, bacteria from the dental biofilm may spread to other parts of the body......-fermenting bacteria causing demineralization of teeth, dental caries, which may further lead to inflammation and necrosis in the pulp and periapical region, i.e., pulpitis and periapical periodontitis. In supra- and subgingival biofilms, predominantly gram-negative, anaerobic proteolytic bacteria will colonize...

  2. Clinical Study Monitoring the pH on Tooth Surfaces in Patients with and without Erosion

    OpenAIRE

    Lussi, Adrian; von Salis-Marincek, Maya; Ganss, Carolina; Hellwig, Elmar; Cheaib, Zeinab; Jaeggi, Thomas

    2012-01-01

    The aim of this study was to compare tooth surface pH after drinking orange juice or water in 39 patients with dental erosion and in 17 controls. The following investigations were carried out: measurement of pH values on selected tooth surfaces after ingestion of orange juice followed by ingestion of water (acid clearance), measurement of salivary flow rate and buffering capacity. Compared with the controls, patients with erosion showed significantly greater decreases in pH after drinking ora...

  3. Evaluation of patients with oral lichenoid lesions by dental patch testing and results of removal of the dental restoration material

    Directory of Open Access Journals (Sweden)

    Emine Buket Şahin

    2016-12-01

    Full Text Available Background and Design: Oral lichenoid lesions (OLL are contact stomatitis characterized by white reticular or erosive patches, plaque-like lesions that are clinically and histopathologically indistinguishable from oral lichen planus (OLP. Amalgam dental fillings and dental restoration materials are among the etiologic agents. In the present study, it was aimed to evaluate the standard and dental series patch tests in patients with OLL in comparison to a control group and evaluate our results. Materials and Methods: Thirty-three patients with OLL or OLP and 30 healthy control subjects, who had at least one dental restoration material and/or dental filling, were included in the study. Both groups received standard series and dental patch test and the results were evaluated simultaneously. Results: The most frequent allergens in the dental series patch test in the patient group were palladium chloride (n=4; 12.12% and benzoyl peroxide (n=2, 6.06%. Of the 33 patients with OLL; 8 had positive reaction to allergents in the standard patch test series and 8 had positive reaction in the dental patch test series. There was no significant difference in the rate of patch test reaction to the dental and standard series between the groups. Ten patients were advised to have the dental restoration material removed according to the results of the patch tests. The lesions improved in three patients [removal of all amalgam dental fillings (n=1, replacement of all amalgam dental fillings with an alternative filling material (n=1 and replacement of the dental prosthesis (n=1] following the removal or replacement of the dental restoration material. Conclusion: Dental patch test should be performed in patients with OLL and dental restoration material. Dental filling and/or prosthesis should be removed/replaced if there is a reaction against a dental restoration material-related allergen.

  4. Diagnosis and treatment of abnormal dental pain

    OpenAIRE

    Fukuda, Ken-ichi

    2016-01-01

    Most dental pain is caused by an organic problem such as dental caries, periodontitis, pulpitis, or trauma. Diagnosis and treatment of these symptoms are relatively straightforward. However, patients often also complain of abnormal dental pain that has a non-dental origin, whose diagnosis is challenging. Such abnormal dental pain can be categorized on the basis of its cause as referred pain, neuromodulatory pain, and neuropathic pain. When it is difficult to diagnose a patient's dental pain, ...

  5. Salivary parameters and teeth erosions in patients with gastroesophageal reflux disease

    Directory of Open Access Journals (Sweden)

    Maria Carolina Canteras Scarillo Falotico Corrêa

    2012-09-01

    Full Text Available CONTEXT: In the gastroesophageal reflux disease (GERD, a highly prevalent digestive disorder, gastric content may return to the esophagus and reach the mouth, thus leading to a small number of carious lesions and high incidence of dental erosion. Since saliva plays a major role in oral homeostasis, evaluating salivary parameters is necessary in attempting to explain such outcome. OBJECTIVES: This study aimed at analyzing salivary parameters (salivary flow, pH and buffering capacity, bacterial count, caries index and dental erosion in patients with GERD. MATERIALS: Sixty patients were studied, and of these, 30 had GERD (group 1, and 30 were controls (group 2. Gastroesophageal reflux disease diagnosis confirmation was achieved by means of endoscopy, manometry and pH metric esophageal monitoring. The above mentioned salivary parameters were evaluated in patients from groups 1 and 2. RESULTS: The number of erosions in patients with GERD (group 1 was larger than in controls (P<0.001. The number of carious teeth was smaller in group 1 than in group 2 (P<0.001. Salivary flow (non-stimulated and stimulated and pH did not show differences between the 2 groups (P = 0.49; P = 0.80 and P = 0.85, respectively. Salivary buffering capacity in patients with GERD showed lower values in controls (P = 0.018. The number of bacteria (Lactobacilli and Streptococci was smaller in patients with gastroesophageal reflux disease than in controls (P = 0.0067 and P = 0.0017, respectively. CONCLUSION: It was concluded that the large number of erosions must be a result of GERD patients reduced salivary buffering capacity. The reduced number of caries of patients in group 1 can be explained by the low prevalence of bacteria (Lactobacilli and Streptococci, observed in the saliva of patients with chronic reflux.

  6. Rethinking erosion on Java: a reaction

    NARCIS (Netherlands)

    Graaff, de J.; Wiersum, K.F.

    1992-01-01

    In a recent article (Diemont et al., 1991) about erosion on Java, it has been postulated that low inputs, not surface erosion, is the main cause of low productivity of upland food crops on this island. In this article it is argued that this hypothesis is too simple. An analysis of empirical field

  7. Optimization of Adhesive Pastes for Dental Caries Prevention.

    Science.gov (United States)

    Sodata, Patteera; Juntavee, Apa; Juntavee, Niwut; Peerapattana, Jomjai

    2017-11-01

    Dental caries prevention products available on the market contain only remineralizing agents or antibacterial agents. This study aimed to develop adhesive pastes containing calcium phosphate and α-mangostin for dental caries prevention using the optimization technique. Calcium phosphate was used as a remineralizing agent, and extracted α-mangostin was used as an antibacterial agent. The effect of the independent variables, which were fumed silica, Eudragit ® EPO, polyethylene glycol, and ethyl alcohol, on the responses was investigated. The drying time, erosion rate, calcium release rate, and α-mangostin release rate were established as the measured responses. An equation and a model of the relationship were constructed. An optimal formulation was obtained, and its effect on dental caries prevention was investigated using the pH-cycling model. The quadratic equation revealed that the drying time, calcium release rate, and α-mangostin release rate tended to decrease when increasing the fumed silica and decreasing other factors. The erosion rate tended to increase when decreasing Eudragit ® EPO and increasing other factors. The observed responses of the optimal adhesive pastes were not significantly different from the predicted responses. This result demonstrated that optimization is an efficient technique in the formulation development of the adhesive pastes. In addition, the optimal adhesive pastes could enhance acid resistance activity to the tooth enamel.

  8. WinDAM C earthen embankment internal erosion analysis software

    Science.gov (United States)

    Two primary causes of dam failure are overtopping and internal erosion. For the purpose of evaluating dam safety for existing earthen embankment dams and proposed earthen embankment dams, Windows Dam Analysis Modules C (WinDAM C) software will simulate either internal erosion or erosion resulting f...

  9. Stress Among Dental Students

    NARCIS (Netherlands)

    A.M. Alzahem (Abdullah)

    2015-01-01

    markdownabstractAbstract Dental students are facing many stressors in dental education, causing many negative outcomes. The most common are the exams and the clinical requirements. We suggest exposing the dental students to patient care as early as possible in their curriculum. This can help to

  10. A retrospective evaluation of traumatic dental injury in children who applied to the dental hospital, Turkey.

    Science.gov (United States)

    Sari, M E; Ozmen, B; Koyuturk, A E; Tokay, U; Kasap, P; Guler, D

    2014-01-01

    The purpose of this study was to analyze traumatic dental injuries in children visiting the dental hospital emergency department in Samsun of Turkey, in the period from 2007 to 2011. Data of age, gender, causes of dental trauma, injured teeth, type of dental injuries, the application period, the dental treatments, and traumatic dental injuries according to the seasons were obtained from the records at dental hospital. Of all 320 patients with traumatic dental injury, 205 were boys and 115 were girls with a boys/girls ratio 1.78:1. Traumatic dental injury was observed more frequently in the 7-12 age groups: 52.5% in girls and 67.8% in boys. Falls are the major cause of traumatic dental injury in the age group 6-12 (51.4%). Sport activities are a common cause of traumatic dental injury in the 7-12 age group (34.2%). Patients visited a dentist within approximately 2 h (57.1%). The upper anterior teeth were subjected to trauma more frequently than the lower anterior teeth. The maxillary central incisors were the most commonly affected teeth, and the mandibular canins were the least affected teeth. In primary teeth, avulsion was the most common type of dental injury (23%); on the other hand, enamel fractures were the most common type of dental injury (30.6%) observed in permanent teeth. In the primary dentition, the most commonly performed treatments were dental examination and prescribing (70%). The most common treatment choices in permanent teeth were restoration and dental examination (49.7 and 15.8%, respectively). The results of the study show that the emergency intervention to traumatized teeth is important for good prognosis of teeth and oral tissues. Therefore, the parents should be informed about dental trauma in schools, and dental hospital physicians should be subjected to postgraduate training.

  11. On the geoethical implications of wind erosion

    Science.gov (United States)

    Károly, Tatárvári

    2016-04-01

    Human activities exerts an ever growing impact on our environment, and this is undeniably the responsibility of mankind. In spite of this fact there is almost no process in our environment that can be described exactly with complete exactness, and the working of which is known in full extent. Wind erosion is such a process. Although water erosion is mentioned ever more often in scientific circles as a from of erosion, its effect is restrained to a certain region, although it may cause perceptibly damage of a greater extent in short time. Wind erosion, apart from the fact that it may have global impact, may play an important role in the warming of our climate according to recent studies. First of all, wind erosion may cause damage far from its origin in human health, nutrition, or in the environment in general. Today several surveys have proved, that erosion caused by wind significantly contributes to the air pollution of cities, the fine dust carried as drift by the wind may cause severe environmental damage in accumulation zones. Microbes, toxic material may attach themselves to the dust carried this way and carried on and by the wings of the wind they may cause health issues in humans animals and plants as well. In spite of these facts there are almost no measures against wind erosion employed in arable land, although our ever doughtier climate and changes would make these necessary. Reduction of organic matter content presents a great problem in a large part of cultivated land, so the risk of the production of high quality food raises questions of more and more ethical nature. Who is responsible? The fact, that the chemicals used in a growing extent by agriculture may reach many people causing considerable damage to the environment also raises serious ethical questions. More and more periods with extreme weather conditions are experienced in Hungary and Europe as the effect of climate change. Drought periods are longer and more frequent as the intensity of

  12. Does pneumoconiosis of dental technician cause to calcific pleural lesions? (Case report

    Directory of Open Access Journals (Sweden)

    Abdurrahman ŞENYİĞİT

    2009-03-01

    Full Text Available The articles about various pneumoconiosis in dental technicians who work in inconvenient conditions have been increasing in recent years. Exposure to dust and fume that occur during the dental procedure may play role in pneumoconiosis of dental technicians.A 53 years old male patient conveyed that he has worked in dental prosthesis procedures for 22 years (1968-1990.Environmental asbestosis was not established in the history of the case but there were calcified pleural plaques in the chest x-ray graphy.There were appearance of calcific asbest plaques in many section of thorax CT.A case of pneumoconiosis in dental technician who work in unadequate preventive conditions was reported in this paper. Probably ,exposure to the asbest fibers that occurs during the procedure of dental prosthesis were the main reason for developing calcific pleural lesions.

  13. Erosive and cariogenicity potential of pediatric drugs: study of physicochemical parameters.

    Science.gov (United States)

    Xavier, Alidianne Fábia C; Moura, Eline F F; Azevedo, Waldeneide F; Vieira, Fernando F; Abreu, Mauro H N G; Cavalcanti, Alessandro L

    2013-12-10

    Pediatric medications may possess a high erosive potential to dental tissues due to the existence of acid components in their formulations. The purpose was to determine the erosive and cariogenic potential of pediatric oral liquid medications through the analysis of their physicochemical properties in vitro. A total of 59 substances were selected from the drug reference list of the National Health Surveillance Agency (ANVISA), which belong to 11 therapeutic classes, as follows: analgesics, non-steroidal anti-inflammatory, corticosteroids, antihistamines, antitussives, bronchodilators, antibacterials, antiparasitics, antiemetics, anticonvulsants and antipsychotics. Measurement of pH was performed by potentiometry, using a digital pH meter. For the Total Titratable Acidity (TTA) chemical assay, a 0.1 N NaOH standard solution was used, which was titrated until drug pH was neutralized. The Total Soluble Solids Contents (TSSC) quantification was carried out by refractometry using Brix scale and the analysis of Total Sugar Content was performed according to Fehling's method. In addition, it was analyzed the information contained in the drug inserts with regard to the presence of sucrose and type of acid and sweetener added to the formulations. All drug classes showed acidic pH, and the lowest mean was found for antipsychotics (2.61 ± 0.08). There was a large variation in the TTA (0.1% - 1.18%) and SST (10.44% - 57.08%) values. High total sugar contents were identified in the antitussives (53.25%) and anticonvulsants (51.75%). As described in the drug inserts, sucrose was added in 47.5% of the formulations, as well as citric acid (39.0%), sodium saccharin (36.4%) and sorbitol (34.8%). The drugs analyzed herein showed physicochemical characteristics indicative of a cariogenic and erosive potential on dental tissues. Competent bodies' strategies should be implemented in order to broaden the knowledge of health professionals, drug manufacturers and general consuming public

  14. Fundamental study on cavitation erosion in liquid metal. Effect of liquid parameter on cavitation erosion in liquid metals (Joint research)

    International Nuclear Information System (INIS)

    Hattori, Shuji; Kurachi, Hiroaki; Inoue, Fumitaka; Watashi, Katsumi; Tsukimori, Kazuyuki; Yada, Hiroki; Hashimoto, Takashi

    2009-02-01

    Cavitation erosion, which possibly occurs on the surfaces of fluid machineries and components contacting flowing liquid and causes sponge-like damage on the material surface, is important problem, since it may become the cause of performance deduction, life shortening, noise, vibration of mechanical components and moreover failure of machine. Research on cavitation erosion in liquid metal is very important to confirm the safety of fast breeder reactor using sodium coolant and to avoid serious damage of the target vessel of spallation neutron source containing liquid-mercury. But the research on cavitation erosion in liquid metal has been hardly performed because of its specially in comparison with that in water. In this study, a cavitation erosion test apparatus was developed to carry out the erosion tests in low-temperature liquid metals. Cavitation erosion tests were carried out in liquid lead-bismuth alloy and in deionized water. We discuss the effect of liquid parameters and temperature effects on the erosion rate. We reach to the following conclusions. The erosion rate was evaluated in terms of a relative temperature which was defind as the percentage between freezing and boiling points. At 14degC relative temperature, the erosion rate is 10 times in lead-bismuth alloy, and 2 to 5 times in sodium, compared with that in deionized water. At 14degC relative temperature, the erosion rate can be evaluated in terms of the following parameter. 1 / (1/ρ L /C L +1/ρ S C S )√ρ L . Where ρ is the material density and c is the velocity of sound, L and S denote liquid and solid. In the relative temperature between 14 and 30degC, the temperature dependence on the erosion rate is due to the increase in vapor pressure. (author)

  15. Understanding the chemistry of dental erosion.

    Science.gov (United States)

    Featherstone, J D B; Lussi, Adrian

    2006-01-01

    The mineral in our teeth is composed of a calcium-deficient carbonated hydroxyapatite (Ca10-xNax(PO4)6-y(CO3)z(OH)2-uFu). These substitutions in the mineral crystal lattice, especially carbonate, renders tooth mineral more acid soluble than hydroxyapatite. During erosion by acid and/or chelators, these agents interact with the surface of the mineral crystals, but only after they diffuse through the plaque, the pellicle, and the protein/lipid coating of the individual crystals themselves. The effect of direct attack by the hydrogen ion is to combine with the carbonate and/or phosphate releasing all of the ions from that region of the crystal surface leading to direct surface etching. Acids such as citric acid have a more complex interaction. In water they exist as a mixture of hydrogen ions, acid anions (e.g. citrate) and undissociated acid molecules, with the amounts of each determined by the acid dissociation constant (pKa) and the pH of the solution. Above the effect of the hydrogen ion, the citrate ion can complex with calcium also removing it from the crystal surface and/or from saliva. Values of the strength of acid (pKa) and for the anion-calcium interaction and the mechanisms of interaction with the tooth mineral on the surface and underneath are described in detail.

  16. Ecological site-based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands

    Science.gov (United States)

    Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.

    2014-01-01

    Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of

  17. Ecological site‐based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands.

    Science.gov (United States)

    Webb, Nicholas P; Herrick, Jeffrey E; Duniway, Michael C

    Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explored how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting, and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass–succulent states across the ecological sites at the plot scale (0.25 ha). We identified vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area could be effectively controlled when bare ground cover was 100 cm in length was less than ∼35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the

  18. Dental Wear: A Scanning Electron Microscope Study

    Directory of Open Access Journals (Sweden)

    Luca Levrini

    2014-01-01

    Full Text Available Dental wear can be differentiated into different types on the basis of morphological and etiological factors. The present research was carried out on twelve extracted human teeth with dental wear (three teeth showing each type of wear: erosion, attrition, abrasion, and abfraction studied by scanning electron microscopy (SEM. The study aimed, through analysis of the macro- and micromorphological features of the lesions (considering the enamel, dentin, enamel prisms, dentinal tubules, and pulp, to clarify the different clinical and diagnostic presentations of dental wear and their possible significance. Our results, which confirm current knowledge, provide a complete overview of the distinctive morphology of each lesion type. It is important to identify the type of dental wear lesion in order to recognize the contributing etiological factors and, consequently, identify other more complex, nondental disorders (such as gastroesophageal reflux, eating disorders. It is clear that each type of lesion has a specific morphology and mechanism, and further clinical studies are needed to clarify the etiological processes, particularly those underlying the onset of abfraction.

  19. The erosive effects of some mouthrinses on enamel. A study in situ.

    Science.gov (United States)

    Pontefract, H; Hughes, J; Kemp, K; Yates, R; Newcombe, R G; Addy, M

    2001-04-01

    There are both anecdotal clinical and laboratory experimental data suggesting that low pH mouthrinses cause dental erosion. This evidence is particularly relevant to acidified sodium chlorite (ASC) formulations since they have plaque inhibitory properties comparable to chlorhexidine but without the well known local side effects. Studies in situ and in vitro were planned to measure enamel erosion by low pH mouthrinses. The study in situ measured enamel erosion by ASC, essential oil and hexetidine mouthrinses over 15-day study periods. The study was a 5 treatment, single blind cross over design involving 15 healthy subjects using orange juice, as a drink, and water, as a rinse, as positive and negative controls respectively. 2 enamel specimens from unerupted human third molar teeth were placed in the palatal area of upper removable acrylic appliances which were worn from 9 a.m. to 5 p.m., Monday to Friday for 3 weeks. Rinses were used 2x daily and 250 ml volumes of orange juice were imbibed 4x daily. Enamel loss was determined by profilometry on days 5, 10 and 15. The study in vitro involved immersing specimens in the 4 test solutions together with a reduced acid ASC formulation for a period of 4 h under constant stirring; Enamel loss was measured by profilometry every hour. Enamel loss was in situ progressive over time with the 3 rinses and orange juice but negligible with water. ASC produced similar erosion to orange juice and significantly more than the two proprietary rinses and water. The essential oil and hexetidine rinses produced similar erosion and significantly more than water. Enamel loss in vitro was progressive over time, and the order from low to high erosion was reduced acid ASC, ASC, Essential oil, and hexetidine mouthrinses and orange juice. Based on the study in situ, it is recommended that low pH mouthrinses should not be considered for long term or continuous use and never as pre-brushing rinses. In view of the plaque inhibitory efficacy of ASC

  20. Effect of titanium tetrafluoride, amine fluoride and fluoride varnish on enamel erosion in vitro

    NARCIS (Netherlands)

    Vieira, A; Ruben, JL; Huysmans, MCDNJM

    2005-01-01

    This study aimed at evaluating the effect of 1 and 4% titanium tetrafluoride (TiF4) gels, amine fluoride (AmF) 1 and 0.25% and a fluoride varnish (FP) on the prevention of dental erosion. Two experimental groups served as controls, one with no pretreatment and another one pre-treated with a

  1. Varioliform erosions in the stomach and duodenum

    Energy Technology Data Exchange (ETDEWEB)

    Lotz, W.; Schulz, D.; Munkel, G.

    1984-04-01

    One thousand five hundred and eighty-three patients who were x-rayed for dyspepsia showed varioliform erosions in 15.3%. Men had an incidence of 9.8%, almost twice as common as in women (5.5%). Mucosal polyps, usually of the hyperplastic type, occurred in 2.4%. 15% of patients with gastric ulcers and 16% of patients with duodenal ulcers had varioliform erosions. On the other hand, amongst patients with erosions, 11% had gastric ulcers and 8.3% duodenal ulcers. The definitions of erosion which have been given in the literature are partly contradictory, and are discussed. Varioliform erosions, also known as complete erosions, may be acute or chronic. They are the third most common cause of bleeding from the upper gastrointestinal tract. With modern radiological methods of examining the stomach, they are no longer a rare finding. 5 figs.

  2. Varioliform erosions in the stomach and duodenum

    International Nuclear Information System (INIS)

    Lotz, W.; Schulz, D.; Munkel, G.

    1984-01-01

    One thousand five hundred and eighty-three patients who were x-rayed for dyspepsia showed varioliform erosions in 15.3%. Men had an incidence of 9.8%, almost twice as common as in women (5.5%). Mucosal polyps, usually of the hyperplastic type, occurred in 2.4%. 15% of patients with gastric ulcers and 16% of patients with duodenal ulcers had varioliform erosions. On the other hand, amongst patients with erosions, 11% had gastric ulcers and 8.3% duodenal ulcers. The definitions of erosion which have been given in the literature are partly contradictory, and are discussed. Varioliform erosions, also known as complete erosions, may be acute or chronic. They are the third most common cause of bleeding from the upper gastrointestinal tract. With modern radiological methods of examining the stomach, they are no longer a rare finding. (orig.) [de

  3. Erosive Lichen Planus.

    Science.gov (United States)

    Mauskar, Melissa

    2017-09-01

    Lichen planus is an inflammatory mucocutaneous condition with a myriad of clinical manifestations. There are 3 forms of lichen planus that effect the vulva: papulosquamous, hypertrophic, and erosive. Erosive lichen planus can progress to vulvar scaring, vaginal stenosis, and squamous cell carcinoma; these long-term sequelae cause sexual distress, depression, and decreased quality of life for patients. Diagnosis is often delayed because of patient embarrassment or clinician misdiagnosis. Early recognition and treatment is essential to decreasing the morbidity of this condition. Multimodal treatment, along with a multidisciplinary approach, will improve outcomes and further clinical advances in studying this condition. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Divertor erosion in DIII-D

    International Nuclear Information System (INIS)

    Whyte, D.G.; Bastasz, R.; Wampler, W.R.; Brooks, J.N.; West, W.P.; Wong, C.P.C.

    1998-05-01

    Net erosion rates of carbon target plates have been measured in situ for the DIII-D lower divertor. The principal method of obtaining this data is the DiMES sample probe. Recent experiments have focused on erosion at the outer strike-point of two divertor plasma conditions: (1) attached (Te > 40 eV) ELMing plasmas and (2) detached (Te 10 cm/year, even with incident heat flux 2 . In this case, measurements and modeling agree for both gross and net carbon erosion, showing the near-surface transport and redeposition of the carbon is well understood and that effective sputtering yields are > 10%. In ELM-free discharges, this erosion rate can account for the rate of carbon accumulation in the core plasma. Divertor plasma detachment eliminates physical sputtering, while spectroscopically measured chemical erosion yields are also found to be low (Y(C/D + ) ≤ 2.0 x 10 -3 ). This leads to suppression of net erosion at the outer strike-point, which becomes a region of net redeposition (∼ 4 cm/year). The private flux wall is measured to be a region of net redeposition with dense, high neutral pressure, attached divertor plasmas. Leading edges intercepting parallel heat flux (∼ 50 MW/m 2 ) have very high net erosion rates (∼ 10 microm/s) at the OSP of an attached plasma. Leading edge erosion, and subsequent carbon redeposition, caused by tile gaps can account for half of the deuterium codeposition in the DIII-D divertor

  5. [Dental care in pregnancy. Ten questions and answers].

    Science.gov (United States)

    Patcas, Raphael; Schmidlin, Patrick R; Zimmermann, Roland; Gnoinski, Wanda

    2012-01-01

    Dental care of pregnant patients is a demanding task. On one hand, clinicians are facing patients with an altered physiology that may cause a greater need for treatment. On the other hand, pregnancy in itself as well as the unborn child involves potential contraindications to dental interventions. It is therefore essential that dentists be knowledgeable of the ramifications pregnancy has on medical findings and therapy. Also, clinicians must be able to conduct their treatment based on well-grounded data to avoid any harm to the pregnant woman and her unborn child. This article focuses on facts specifically relevant to clinicians. Based on most current scientific data, we aim to answer the following ten questions: 1. What are the physiological changes during pregnancy? 2. What is the adequate lying position for a pregnant patient? 3. Is there a pregnancy-related gingivitis? 4. What is the association between periodontitis, pregnancy and preterm birth? 5. Are there oral manifestations of pregnancy-related therapies? 6. Are caries and erosions inevitable during pregnancy? 7. Should the intake of fluoride be advocated? 8. Is it permissible to x-ray pregnant patients? 9. Is orthodontics contraindicated during pregnancy and 10. Which medication should be administered with caution?

  6. Modeling the reduction in soil loss due to soil armouring caused by rainfall erosion

    Science.gov (United States)

    Surface soil properties can change as a result of soil disturbances, erosion, or deposition. One process that can significantly change surface soil properties is soil armouring, which is the selective removal of finer particles by rill or interrill erosion, leaving an armoured layer of coarser parti...

  7. EVALUATION OF SOIL EROSION IN REGHIN HILLS USING THE USLE METHOD

    Directory of Open Access Journals (Sweden)

    J. SZILAGYI

    2016-03-01

    Full Text Available Soil erosion is one of the main causes of degradation of large areas of agricultural land, causing great economic loss by removing fertile soil. The Universal Soil Loss Equation (USLE predicts the long term average annual rate of erosion on a field slope based on rainfall pattern, soil type, topography, crop system and management practices but does not however predict the soil loss resulting from gully erosion.

  8. Numerical Modelling and Prediction of Erosion Induced by Hydrodynamic Cavitation

    Science.gov (United States)

    Peters, A.; Lantermann, U.; el Moctar, O.

    2015-12-01

    The present work aims to predict cavitation erosion using a numerical flow solver together with a new developed erosion model. The erosion model is based on the hypothesis that collapses of single cavitation bubbles near solid boundaries form high velocity microjets, which cause sonic impacts with high pressure amplitudes damaging the surface. The erosion model uses information from a numerical Euler-Euler flow simulation to predict erosion sensitive areas and assess the erosion aggressiveness of the flow. The obtained numerical results were compared to experimental results from tests of an axisymmetric nozzle.

  9. Reduction of surface erosion in fusion reactors

    International Nuclear Information System (INIS)

    Rossing, T.D.; Das, S.K.; Kaminsky, M.

    1976-01-01

    Some of the major processes leading to surface erosion in fusion reactors are reviewed briefly, including blistering by implanted gas, sputtering by ions, atoms, and neutrons, and vaporization by local heating. Surface erosion affects the structural integrity and limits the lifetime of reactor components exposed to plasma radiation. In addition, some of the processes leading to surface erosion also cause the release of plasma contaminants. Methods proposed to reduce surface erosion have included control of surface temperature, selection of materials with a favorable microstructure, chemical and mechanical treatment of surfaces, and employment of protective surface coatings, wall liners, and divertors. The advantages and disadvantages of some of these methods are discussed

  10. Runoff erosion

    OpenAIRE

    Evelpidou, Niki (Ed.); Cordier, Stephane (Ed.); Merino, Agustin (Ed.); Figueiredo, Tomás de (Ed.); Centeri, Csaba (Ed.)

    2013-01-01

    Table of Contents PART I – THEORY OF RUNOFF EROSION CHAPTER 1 - RUNOFF EROSION – THE MECHANISMS CHAPTER 2 - LARGE SCALE APPROACHES OF RUNOFF EROSION CHAPTER 3 - MEASURING PRESENT RUNOFF EROSION CHAPTER 4 - MODELLING RUNOFF EROSION CHAPTER 5 - RUNOFF EROSION AND HUMAN SOCIETIES: THE INFLUENCE OF LAND USE AND MANAGEMENT PRACTICES ON SOIL EROSION PART II - CASE STUDIES CASE STUDIES – INTRODUCTION: RUNOFF EROSION IN MEDITERRANEAN AREA CASE STUDY 1: Soil Erosion Risk...

  11. Dental wear caused by association between bruxism and gastroesophageal reflux disease: a rehabilitation report

    Directory of Open Access Journals (Sweden)

    Naila Aparecida de Godoi Machado

    2007-08-01

    Full Text Available Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks, periodontal signs (gingival recession and tooth mobility and muscle-joint sensivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO for reestablishment of the occlusal stability, vertical dimension of occlusion, anterior guides and return to normal muscle activity (90-day use approximately. After remission of initial symptoms, oral rehabilitation was implemented in CRO by means of full resin composite restorations and new interocclusal device for protection of restorations. Satisfactory esthetics, improved function and occlusal stability were obtained after oral rehabilitation. The patient has attended annual follow-ups for the past 2 years. The multidisciplinary treatment seems to be the key for a successful rehabilitation of severe cases of dental wear involving the association of different health disorders.

  12. Dental wear caused by association between bruxism and gastroesophageal reflux disease: a rehabilitation report.

    Science.gov (United States)

    Machado, Naila Aparecida de Godoi; Fonseca, Rodrigo Borges; Branco, Carolina Assaf; Barbosa, Gustavo Augusto Seabra; Fernandes Neto, Alfredo Júlio; Soares, Carlos José

    2007-08-01

    Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks), periodontal signs (gingival recession and tooth mobility) and muscle-joint sensitivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO) for reestablishment of the occlusal stability, vertical dimension of occlusion, anterior guides and return to normal muscle activity (90-day use approximately). After remission of initial symptoms, oral rehabilitation was implemented in CRO by means of full resin composite restorations and new interocclusal device for protection of restorations. Satisfactory esthetics, improved function and occlusal stability were obtained after oral rehabilitation. The patient has attended annual follow-ups for the past 2 years. The multidisciplinary treatment seems to be the key for a successful rehabilitation of severe cases of dental wear involving the association of different health disorders.

  13. Metallic artifacts caused by dental metal prostheses on PET images. A PET/CT phantom study using different PET/CT scanners

    International Nuclear Information System (INIS)

    Shimamoto, Hiroaki; Kakimoto, Naoya; Murakami, Shumei; Furukawa, Souhei; Fujino, Kouichi; Hamada, Seiki; Shimosegawa, Eku; Hatazawa, Jun

    2009-01-01

    The objective of this study was to investigate the effects of computed tomography (CT) artifacts caused by dental metal prostheses on positron emission tomography (PET) images. A dental arch cast was fixed in a cylindrical water-bath phantom. A spherical phantom positioned in the vicinity of the dental arch cast was used to simulate a tumor. To simulate the tumor imaging, the ratio of the 18 F-fluoro-deoxy-glucose radioactivity concentration of the spherical phantom to that of the water-bath phantom was set at 2.5. A dental bridge composed of a gold-silver-palladium alloy on the right mandibular side was prepared. A spherical phantom was set in the white artifact area on the CT images (site A), in a slightly remote area from the white artifact (site B), and in a black artifact area (site C). A PET/CT scan was performed with and without the metal bridge at each simulated tumor site, and the artifactual influence was evaluated on the axial attenuation-corrected (AC) PET images, in which the simulated tumor produced the strongest accumulation. Measurements were performed using three types of PET/CT scanners (scanners 1 and 2 with CT-based attenuation correction, and 3 with Cesium-137 ( 137 Cs)-based attenuation correction). The influence of the metal bridge was evaluated using the change rate of the SUVmean with and without the metal bridge. At site A, an overestimation was shown (scanner 1: +5.0% and scanner 2: +2.5%), while scanner 3 showed an underestimation of -31.8%. At site B, an overestimation was shown (scanner 1: +2.1% and scanner 2: +2.0%), while scanner 3 showed an underestimation of -2.6%. However, at site C, an underestimation was shown (scanner 1: -25.0%, scanner 2: -32.4%, and scanner 3: -8.4%). When CT is used for attenuation correction in patients with dental metal prostheses, an underestimation of radioactivity of accumulated tracer is anticipated in the dark streak artifact area on the CT images. In this study, the dark streak artifacts of the CT

  14. Modeling erosion of unsaturated compacted bentonite by groundwater flow; pinhole erosion test case

    International Nuclear Information System (INIS)

    Laurila, T.; Sane, P.; Olin, M.; Koskinen, K.

    2012-01-01

    Document available in extended abstract form only. Erosion of compacted clay material by water flow is a critical factor affecting the performance of radioactive waste confinement. Our emphasis in this work is the buffer of KBS-3V concept, proposed to be compacted MX-80 bentonite. Unsaturated erosion occurs during the saturation phase of the EBS, and the main quantity of interest is the total buffer mass carried away by a groundwater flow that induces erosion by forming piping channels near the buffer/rock interface. The purpose of this work is to provide modeling tools to support erosion experiments. Role of modeling is first to interpret experimental observations in terms of processes, and to estimate robustness of experimental results. Secondly, we seek to scale up results from the laboratory scale, particularly to time scales longer than those experimentally accessible. We have performed modeling and data analysis pertaining to tests of unsaturated clay erosion. Pinhole experiments were used to study this erosion case. The main differences to well-understood pinhole erosion tests are that the material is strongly swelling and that the water flow is not determined by the pressure head but by the total flux. Groundwater flow in the buffer is determined by the flux because pressure losses occur overwhelmingly in the surrounding rock, not in the piping channel. We formulate a simple model that links an effective solid diffusivity -based swelling model to erosion by flow on the solid/liquid interface. The swelling model is similar in concept to that developed at KTH, but simpler. Erosion in the model is caused by laminar flow in the pinhole, and happens in a narrow region at the solid/liquid interface where velocity and solid volume fraction overlap. The erosion model can be mapped to erosion by wall shear, and can thus be considered as extension of that classic erosion model. The main quantity defining the behavior of clay erosion in the model is the ratio of

  15. Erosive effects of acidic center-filled chewing gum on primary and permanent enamel

    Directory of Open Access Journals (Sweden)

    Bolan M

    2008-01-01

    Full Text Available Background: The higher incidence of dental erosion in children and teenagers possibly reflects a high intake of acidic food and beverages as well as a more frequent diagnosis on this condition. Aim: The aim of this study was to evaluate the erosive potential of acidic filling of chewing gum in primary and permanent enamel. Methods and Materials: Eighty enamel blocks (40 primary and 40 permanent teeth were used and randomly distributed into eight groups. Groups were divided according to types of dental substrates (permanent or primary, frequency of exposure to the acidic substance (2X or 4X/day, and concentration (pure or diluted. Exposure time to the acidic content of the chewing gum was five minutes under agitation, during five days. Results: All groups showed a significant decrease in surface microhardness (P < 0.001. There was neither any significant difference in the frequency of exposure to the acidic content nor to the types of dental substrates. There was a statistically significant difference between D1 (pure, 2X/day and D2 (diluted, 2X/day (P = 0.002, D3 (pure, 4X/day and D4 (diluted, 4X/day (P = 0.009 regarding the concentration, then the diluted acid content was associated with a greater decrease in microhardness. Conclusion: It is concluded that the acidic filling of a chewing gum reduced the microhardness of primary and permanent enamel.

  16. Erosion and stability of a mine soil

    International Nuclear Information System (INIS)

    Wu, T.H.; Stadler, A.T.; Low, C.

    1996-01-01

    Mine soils developed from mine spoils commonly have a wide range of particle size. The slopes of old spoil piles usually are marked by gullies due to years of uncontrolled erosion. These characteristics raise questions about applicability of available theories and models for estimating runoff and erosion. An investigation was made to determine whether available erosion models can work for mine soils and can account for gully erosion. The investigation at an abandoned surface mine consisted of measurement of soil and sediment properties, measurement of runoff and erosion, observations of armor by rock fragments on gully floor, and calculations with available theories of sediment transport and slope stability. The results at this site suggest that (1) predictions with the ANSWERS model have about the same accuracy as those made for agricultural lands; (2) armor provided by rock fragments are temporary as they are periodically removed by debris flows; (3) detachment by rainfall impact is the primary cause of erosion on short steep slopes; and (4) a simplified method can be used for estimating erosion on such slopes

  17. Erosion control works and the intensity of soil erosion in the upper part of the river Toplica drainage basin

    International Nuclear Information System (INIS)

    Kostadinov, S; Dragovic, N; Zlatic, M; Todosijevic, M

    2008-01-01

    Aiming at the protection of the future storage 'Selova' against erosion and sediment, and also to protect the settlements and roads in the drainage basin against torrential floods, erosion control works in the upper part of the river Toplica basin, upstream of the storage 'Selova', started in 1947. The works included building-technical works (check dams) and biological works (afforestation and grassing of bare lands and other erosion risk areas). Within the period 1947-2006, the following erosion control works were executed: afforestation of bare lands on the slopes 2,257.00 ha, grassing of bare lands 1,520.00 ha, and altogether 54 dams were constructed in the river Toplica tributaries. This caused the decrease of sediment transport in the main flow of the river Toplica. This paper, based on the field research conducted in two time periods: 1988 and in the period 2004-2007, presents the state of erosion in the basin before erosion control works; type and scope of erosion control works and their effect on the intensity of erosion in the river Toplica basin upstream of the future storage 'Selova'.

  18. Aesthetic treatment on anterior teeth crown fracture caused by dental trauma

    Directory of Open Access Journals (Sweden)

    Nanik Zubaidah

    2012-12-01

    Full Text Available Background: Complicated crown fracture is a tooth fracture that involve enamel, dentine and pulp. The incidence of complicated crown fracture ranges from 2% to 13% of all dental injuries and the most commonly involved teeth are the maxillary central incisors. Various treatment modalities are available depending on the clinical, physiological and radiographic examination of the involved teeth. Purpose: The aim of this case report is to present the management of crown fractures with pulpal exposure caused by traumatic injury, through endorestoration approach to reconstruct the shape and function of the teeth. Case: A 17 years old male with complicated crown fractures of anterior teeth #11 #21 and #22. The patient wish for aesthetic dental treatment in both of its form and function. Case management: Crown fractures of anterior teeth with exposed pulp caused by traumatic injury were reconstructed by endorestoration approach. The endodontic treatment with post and core insertion in the root canal which will increase its retention and porcelain fused to metal crown which will aesthetically recover its original form and function. After restoration the patient feel very glad and confident with the result. Conclusion: Endorestoration treatment on anterior teeth with complicated crown fractures and exposed pulp is able to recover the normal form, function and dental aesthetic in accordance with stomatognatic system and self confidence.Latar belakang: Fraktur mahkota kompleks (complicated adalah fraktur pada mahkota gigi yang melibatkan enamel, dentin dan pulpa. Kejadian dari fraktur mahkota kompleks bervariasi antara 2-13% dari semua trauma gigi dan sebagian besar gigi yang terkena adalah gigi insisif pertama rahang atas. Berbagai macam cara perawatan yang dilakukan tergantung pada hasil pemeriksaan klinis, psikologis dan radiografis dari gigi yang terkena. Tujuan: Laporan kasus ini menjelaskan penatalaksanaan fraktur mahkota gigi dengan pulpa terbuka

  19. Soil erosion assessment - Mind the gap

    Science.gov (United States)

    Kim, Jongho; Ivanov, Valeriy Y.; Fatichi, Simone

    2016-12-01

    Accurate assessment of erosion rates remains an elusive problem because soil loss is strongly nonunique with respect to the main drivers. In addressing the mechanistic causes of erosion responses, we discriminate between macroscale effects of external factors - long studied and referred to as "geomorphic external variability", and microscale effects, introduced as "geomorphic internal variability." The latter source of erosion variations represents the knowledge gap, an overlooked but vital element of geomorphic response, significantly impacting the low predictability skill of deterministic models at field-catchment scales. This is corroborated with experiments using a comprehensive physical model that dynamically updates the soil mass and particle composition. As complete knowledge of microscale conditions for arbitrary location and time is infeasible, we propose that new predictive frameworks of soil erosion should embed stochastic components in deterministic assessments of external and internal types of geomorphic variability.

  20. Soil erosion and causative factors at Vandenberg Air Force Base, California

    Science.gov (United States)

    Butterworth, Joel B.

    1988-01-01

    Areas of significant soil erosion and unvegetated road cuts were identified and mapped for Vandenberg Air Force Base. One hundred forty-two eroded areas (most greater than 1.2 ha) and 51 road cuts were identified from recent color infrared aerial photography and ground truthed to determine the severity and causes of erosion. Comparison of the present eroded condition of soils (as shown in the 1986 photography) with that in historical aerial photography indicates that most erosion on the base took place prior to 1928. However, at several sites accelerated rates of erosion and sedimentation may be occurring as soils and parent materials are eroded vertically. The most conspicuous erosion is in the northern part of the base, where severe gully, sheet, and mass movement erosion have occurred in soils and in various sedimentary rocks. Past cultivation practices, compounded by highly erodible soils prone to subsurface piping, are probably the main causes. Improper range management practices following cultivation may have also increased runoff and erosion. Aerial photography from 1986 shows that no appreciable headward erosion or gully sidewall collapse have occurred in this area since 1928.

  1. Divertor erosion in DIII-D

    International Nuclear Information System (INIS)

    Whyte, D.G.; Bastasz, R.; Wampler, W.R.; Brooks, J.N.; West, W.P.; Wong, C.P.C.; Buzhinskij, O.I.; Opimach, I.V.

    1998-08-01

    Net erosion rates of carbon target plates have been measured in situ for the DIII-D lower divertor. The principal method of obtaining this data is the DiMES sample probe. Recent experiments have focused on erosion at the outer strike-point (OSP) of two divertor plasma conditions: attached (T e > 40 eV) ELMing plasmas, and detached (T e 2 . In this case, measurements and modeling agree for both gross and net carbon erosion, showing the near-surface transport and redeposition of the carbon is well understood. In the attached cases, physical sputtering (with enhancement from self-sputtering and oblique incidence) is dominant, and the effective sputtering yield, Y, is greater than 10%. In ELM-free discharges, the total OSP net erosion rate is equal to the rate of carbon accumulation in the core plasma. For the detached divertor cases, the cold incident plasma eliminates physical sputtering. Attempts to measure chemically eroded hydrocarbon molecules spectroscopically indicate an upper limit of Y ≤ 0.1% for the chemical sputtering yield. Net erosion is suppressed at the outer strike-point, which becomes a region of net redeposition (∼ 4 cm/exposure-year). The private flux wall is measured to be a region of net redeposition with dense, high neutral pressure, attached divertor plasmas. Leading edges intercepting parallel heat flux (∼ 50 MW/m 2 ) have very high net erosion rates at the OSP of an attached plasma (∼ 10 microm/s > 1,000x erosion rate of aligned surfaces). Leading edge erosion, and subsequent carbon redeposition, caused by tile gaps can account for half of the deuterium codeposition in the DIII-D divertor

  2. Tanzania Dental Journal Vol. 15 No. 1, May 2008 1

    African Journals Online (AJOL)

    Windows User

    Hellstrom I. Oral complications in anorexia nervosa. Scand J Dent Res 1997; 85: 71-86. 4. Arnadottir IB, Sæmundsson SR, Holbrook. WP. Dental erosion in Icelandic teenagers in relation to dietary and lifestyle factors. Acta. Odontol Scand 2003; 61:25–8. 5. Hooper SM, Newcombe RG, Faller R,. Eversole S, Addy M, West ...

  3. Current status of disinfection of dental impressions in Indian dental colleges: a cause of concern.

    Science.gov (United States)

    Marya, Charu Mohan; Shukla, Prasoon; Dahiya, Vandana; Jnaneswar, Avinash

    2011-11-15

    Dentistry is predominantly a field of surgery, involving exposure to blood and other potentially infectious materials and therefore requires a high standard of infection control and safety practice in controlling cross-contamination and occupational exposures to blood- and saliva-borne diseases. A questionnaire survey was conducted in 60 dental colleges throughout India to establish routine methods of treating impressions of the oral cavity for disinfection. An email describing the purpose of the study along with a short questionnaire was sent to one of the teaching faculty of concerned departments of the colleges. Questions were asked regarding availability of materials required to disinfect the impressions, the preferred method to treat the impression, and whether postgraduate courses were offered by the department. The routine method of treating the impression reported by 75.9% of the respondents was washing under running water, while 24.1% of the respondents reported that impressions were treated by chemical disinfectants. Strict infection control measures are necessary to ensure the health and safety of dental workers and patients. The present study showed that there is a lack of commitment to high standards of infection control practices in dental colleges in India.

  4. Past, Present, Future Erosion at Locke Island

    Energy Technology Data Exchange (ETDEWEB)

    Bjornstad, Bruce N.

    2006-08-08

    This report describes and documents the erosion that has occurred along the northeast side of Locke Island over the last 10 to 20 years. The principal cause of this erosion is the massive Locke Island landslide complex opposite the Columbia River along the White Bluffs, which constricts the flow of the river and deflects the river's thalweg southward against the island.

  5. OCT investigation of dental lesions

    Science.gov (United States)

    Osiac, Eugen; Popescu, Sanda Mihaela; Scrieciu, Monica; Mercuţ, Rǎzvan; Mercuţ, Veronica; Vǎtu, Mihaela

    2018-03-01

    There are several important non carious lesions affecting the tooth structure, lesions which may be classified into four clinical forms of dental wear: abfraction, erosion, attrition and abrasion, and different types of root resorption. Search for new, non-invasive and fast methods able to detect and describe such injuries is of utmost importance. Optical coherence tomography (OCT) proved itself as an appropriate investigation method for several medical fields including ophthalmology, dermatology, cardiology etc. Our study reveals OCT preliminary investigations as a promising tool for detecting and evaluating of the mentioned lesions.

  6. The cariogenic dental biofilm: good, bad or just something to control?

    Directory of Open Access Journals (Sweden)

    Mark Steven Wolff

    2009-06-01

    Full Text Available This paper discusses the role of dental biofilm and adjunctive therapies in the management of dental caries. Dental biofilm is a site of bacterial proliferation and growth, in addition to being a location of acid production. It also serves as a reservoir for calcium exchange between the tooth and saliva. The salivary pellicle, a protein-rich biofilm layer, regulates the reaction between tooth surface, saliva and erosive acids. The protective effects of this pellicle on enamel are well established. However, understanding the effects of the pellicle/biofilm interaction in protecting dentin from erosive conditions requires further research. Saliva interacts with the biofilm, and is important in reducing the cariogenic effects of dental plaque as acidogenic bacteria consume fermentable carbohydrates producing acids that may result in tooth demineralization. Adequate supplies of healthy saliva can provide ingredients for successful remineralization. Strategies for managing the cariogenic biofilm are discussed with emphasis on the effectiveness of over-the-counter (OTC products. However, since many toothpaste components have been altered recently, new clinical trials may be required for true validation of product effectiveness. A new generation of calcium-based remineralizing technologies may offer the ability to reverse the effects of demineralization. Nevertheless, remineralization is a microscopic subsurface phenomenon, and it will not macroscopically replace tooth structure lost in a cavitated lesion. Optimal management of cavitations requires early detection. This, coupled with advances in adhesive restorative materials and microsurgical technique, will allow the tooth to be restored with minimal destruction to nearby healthy tissue.

  7. Pacemaker lead erosion simulating "Loch Ness Monster": conservative management.

    Science.gov (United States)

    Garg, Naveen; Moorthy, Nagaraja

    2012-12-01

    The majority of pacemaker pocket or lead erosions are due to either mechanical erosion by the bulky pulse generator or secondary to pacemaker pocket infection. We describe an unusual case of delayed pacemaker lead erosion causing extrusion of a portion of the pacing lead, with separate entry and exit points, with the gap filled with new skin formation, simulating the "Loch Ness Monster", which was successfully managed conservatively by surgical reinsertion.

  8. In situ effect of CPP-ACP chewing gum upon erosive enamel loss

    Directory of Open Access Journals (Sweden)

    Catarina Ribeiro Barros de ALENCAR

    Full Text Available Abstract Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP is able to increase salivary calcium and phosphate levels at an acidic pH. Previous studies demonstrated that a CPP-ACP chewing gum was able to enhance the re-hardening of erosion lesions, but could not diminish enamel hardness loss. Therefore, there is no consensus regarding the effectiveness of CPP-ACP on dental erosion. Objective This in situ study investigated the ability of a CPP-ACP chewing gum in preventing erosive enamel loss. Material and Methods: During three experimental crossover phases (one phase per group of seven days each, eight volunteers wore palatal devices with human enamel blocks. The groups were: GI – Sugar free chewing gum with CPP-ACP; GII – Conventional sugar free chewing gum; and GIII – No chewing gum (control. Erosive challenge was extraorally performed by immersion of the enamel blocks in cola drink (5 min, 4x/day. After each challenge, in groups CPP and No CPP, volunteers chewed one unit of the corresponding chewing gum for 30 minutes. Quantitative analysis of enamel loss was performed by profilometry (µm. Data were analyzed by Repeated-Measures ANOVA and Tukey’s test (p0.05. Conclusion The CPP-ACP chewing gum was not able to enhance the anti-erosive effect of conventional chewing gum against enamel loss.

  9. The 'sialo-microbial-dental complex' in oral health and disease.

    Science.gov (United States)

    Kaidonis, John; Townsend, Grant

    2016-01-01

    Biofilms are naturally found in all wet environments including the oral structures of nearly all species. Human oral biofilms have existed since our earliest ancestors and have evolved symbiotically with the dentition over many millennia within a Palaeolithic, hunter-gatherer setting. Irrespective of the plant-animal ratio, it can be argued that the Palaeolithic diet was essentially acidic, and acted as a selective force for much of the evolution of the stomatognathic system. The relationship between saliva, biofilm and teeth, the 'sialo-microbial-dental complex', provides oral health benefits and offers a different perspective to the old dental paradigm that only associated oral biofilms (plaque) with disease (caries). This new paradigm emphasises that oral biofilms are essential for the 'mineral maintenance' of teeth. Oral biofilms provide physical protection from dietary acid and together with bacterial metabolic acids cause the resting pH of the biofilm to fall below neutral. This is then followed by the re-establishment of a neutral environment by chemical interactions mediated by the saliva within the biofilm. Such pH fluctuations are often responsible for the cyclic demineralisation, then remineralisation of teeth, a process necessary for tooth maturation. However, since the advent of farming and especially since the industrial revolution, the increase in consumption of carbohydrates, refined sugars and acidic drinks has changed the ecology of biofilms. Biofilm biodiversity is significantly reduced together with a proliferation of acidogenic and aciduric organisms, tipping the balance of the 'demin-remin' cycle towards net mineral loss and hence caries. In addition, the consumption of acidic drinks in today's societies has removed the protective nature of the biofilm, leading to erosion. Erosion and caries are 'modern-day' diseases and reflect an imbalance within the oral biofilm resulting in the demineralisation of teeth. Copyright © 2015 The Authors

  10. Atomic Oxygen Erosion Yield Dependence Upon Texture Development in Polymers

    Science.gov (United States)

    Banks, Bruce A.; Loftus, Ryan J.; Miller, Sharon K.

    2016-01-01

    The atomic oxygen erosion yield (volume of a polymer that is lost due to oxidation per incident atom) of polymers is typically assumed to be reasonably constant with increasing fluence. However polymers containing ash or inorganic pigments, tend to have erosion yields that decrease with fluence due to an increasing presence of protective particles on the polymer surface. This paper investigates two additional possible causes for erosion yields of polymers that are dependent upon atomic oxygen. These are the development of surface texture which can cause the erosion yield to change with fluence due to changes in the aspect ratio of the surface texture that develops and polymer specific atomic oxygen interaction parameters. The surface texture development under directed hyperthermal attack produces higher aspect ratio surface texture than isotropic thermal energy atomic oxygen attack. The fluence dependence of erosion yields is documented for low Kapton H (DuPont, Wilmington, DE) effective fluences for a variety of polymers under directed hyperthermal and isotropic thermal energy attack.

  11. Treatment planning for patients with dental arch asymmetry caused by loss of a premolar on one side of the mouth

    Directory of Open Access Journals (Sweden)

    Ivanova О.P.

    2013-09-01

    Full Text Available The objective of this study is to determine a selection criterion that is applicable for the treatment of patients with dental arch asymmetry caused by loss of a premolar on one side of the mouth. Material and methods. Fifty-seven patients (first maturity level who had some teeth extracted for orthodontic treatment were included in the study. The patients were divided into basic and control groups. We proposed to shape the extraction socket immediately after the extraction of a permanent tooth. In the basic group the extraction sockets were filled with osteoplastic material. Patients in the control group refused any surgical interventions. Results. According to a given criterion, the correlation between tooth size and dental arch parameters has been determined. When applying this criterion for finding the correlation, the frontal distal diagonal size of the dental arch was multiplied by 1.14 coefficient. The sum of the mesiodistal diameters of seven teeth in the half-arc was subtracted from the obtained value. The value which was equal to 0±1.0mm indicated the correlation between tooth size and dental arch parameters. Conclusion. If there is a correlation between tooth size and dental arch parameters, it is advisable to provide treatment associated with having the post-extraction socket opened and implant therapy performed (most commonly with the use of intraosseous dental implants.

  12. Comparative analysis of soil erosion sensitivity using various quantizations within GIS environment

    NARCIS (Netherlands)

    Paparrizos, Spyridon; Maris, Fotios; Kitikidou, Kyriaki; Anastasiou, Theofilos; Potouridis, Simeon

    2015-01-01

    Soil erosion is a prominent cause of land degradation and desertification in Mediterranean countries. The detrimental effects of soil erosion are exemplified in climate (in particular climate change), topography, human activities and natural disasters. Modelling of erosion and deposition in

  13. Erosion protection of uranium tailings impoundments

    International Nuclear Information System (INIS)

    Walters, W.H.; Skaggs, R.L.; Foley, M.G.; Beedlow, P.A.

    1986-09-01

    Pacific Northwest Laboratory (PNL) prepared this report to assist in the design and review of erosion protection works for decommissioned uranium tailings impoundments. The major causes of erosion over the long-term decommissioning period are from rainfall-runoff (overland flow) and stream channel flooding. The method of protection recommended for the impoundment side slopes and site drainage channels is rock riprap. Combinations of vegetation and rock mulch are recommended for the top surface. The design methods were developed from currently available procedures supplemented by field, laboratory, and mathematical model studies performed by PNL. Guidelines for the placement of riprap, inspection, and maintenance are presented. Other subjects discussed are rock selection and testing, slope stability, and overland erosion modeling

  14. Soil erodibility for water erosion: A perspective and Chinese experiences

    Science.gov (United States)

    Wang, Bin; Zheng, Fenli; Römkens, Mathias J. M.; Darboux, Frédéric

    2013-04-01

    Knowledge of soil erodibility is an essential requirement for erosion prediction, conservation planning, and the assessment of sediment related environmental effects of watershed agricultural practices. This paper reviews the status of soil erodibility evaluations and determinations based on 80 years of upland area erosion research mainly in China and the USA. The review synthesizes the general research progress made by discussing the basic concepts of erodibility and its evaluation, determination, and prediction as well as knowledge of its spatio-temporal variations. The authors found that soil erodibility is often inappropriately or inaccurately applied in describing soil loss caused by different soil erosion component processes and mechanisms. Soil erodibility indicators were related to intrinsic soil properties and exogenic erosional forces, measurements, and calculations. The present review describes major needs including: (1) improved definition of erodibility, (2) modified erodibility determinations in erosion models, especially for specific geographical locations and in the context of different erosion sub-processes, (3) advanced methodologies for quantifying erodibilities of different soil erosion sub-processes, and (4) a better understanding of the mechanism that causes temporal variations in soil erodibility. The review also provides a more rational basis for future research on soil erodibility and supports predictive modeling of soil erosion processes and the development of improved conservation practices.

  15. Erosion corrision in water steam circuits - reasons and countermeasures

    International Nuclear Information System (INIS)

    Heitmann, H.G.; Kastner, W.

    An increased material erosion on tubes in steam generators, preheaters and condensers but also on turbine casings and connecting pipes of unalloyed and low-alloy steels occurs, to an essential extent, due to erosion-corrosion processes in the fluid-swept plant sections. On the one hand, they cause thinning of the material and sometimes leaks, on the other hand the erosion material leads to contamination of the water-steam cycle with its harmful consequences. The cause of erosion-corrosion is a dissolving corrosion due to the convective effect of pure fluid turbulences. The occurrence of erosion-corrosion is limited to such metallic materials, which are in need of oxide protection layers for their constancy. The cover layers are destroyed by erosive influence and the formation of new protection layers is prevented. At KWU, experimental studies of plates were carried out in the Benson test section to obtain information about the most important parameters of influence. These are in particular the flow velocity, the medium temperature and the water quality (pH value and oxygen content). Moreover, the resistivity of different materials has been compared and the resistance of magnetite protection layers to erosion-corrosion was examined. The results of these studies deliver fundamentals to avoid erosion-corrosion also in power plant engineering to the greatest possible extent. The following variants reveal to be important: 1. Use of chrome alloy materials. 2. Decrease of the flow velocity. 3. Increase of the pH value or the oxygen content. The importance of the test results for power plant engineering is briefly described. (orig.) [de

  16. Erosion in the Beaches of Crete

    Science.gov (United States)

    Synolakis, C. E.; Foteinis, S.; Voukouvalas, V.; Kalligeris, N.

    2009-04-01

    In the past decade, erosion rates for the coastlines of Greece are rapidly increasing. Many beaches on the northern coast of the island have substantially retreated, while others have disappeared or will disappear within the present or the following decade if no action is taken. For the better understanding and visualization of the current situation, specific examples of rapid erosion are described and afterwards we speculate as to the causes. We infer that, as in other parts of the Mediterranean, the causes are anthropogenic and include removal of sand dunes to build roads, sand mining from beaches and rivers, permanent building construction within the active coastal zone, on or too close to shoreline, and poor design of coastal structures. The reason behind the rapid erosion of Greece coastlines is the complete lack of any semblance of coastal zone management and antiquated legislation. We conclude that unless urgent measures for the protection and even salvation of the beaches are taken and if the sand mining and dune removal does not stop, then several beaches will disappear within the present and the following decade.

  17. Erosion on spark plug electrodes; Funkenerosion an Zuendkerzenelektroden

    Energy Technology Data Exchange (ETDEWEB)

    Rager, J.

    2006-07-01

    Durability of spark plugs is mainly determined by spark gap widening, caused by electrode wear. Knowledge about the erosion mechanisms of spark plug materials is of fundamental interest for the development of materials with a high resistance against electrode erosion. It is therefore crucial to identify those parameters which significantly influence the erosion behaviour of a material. In this work, a reliable and reproducible testing method is presented which produces and characterizes electrode wear under well-defined conditions and which is capable of altering parameters specifically. Endurance tests were carried out to study the dependence of the wear behaviour of pure nickel and platinum on the electrode temperature, gas, electrode gap, electrode diameter, atmospheric pressure, and partial pressure of oxygen. It was shown that erosion under nitrogen is negligible, irrespective of the material. This disproves all common mechanism discussed in the literature explaining material loss of spark plug electrodes. Based on this observation and the variation of the mentioned parameters a new erosion model was deduced. This relies on an oxidation of the electrode material and describes the erosion of nickel and platinum separately. For nickel, electrode wear is caused by the removal of an oxide layer by the spark. In the case of platinum, material loss occurs due to the plasma-assisted formation and subsequent evaporation of volatile oxides in the cathode spot. On the basis of this mechanism a new composite material was developed whose erosion resistance is superior to pure platinum. Oxidation resistant metal oxide particles were added to a platinum matrix, thus leading to a higher erosion resistance of the composite. However, this can be decreased by a side reaction, the separation of oxygen from the metal oxides, which effectively assists the oxidation of the matrix. This reaction can be suppressed by using highly stable oxides, characterized by a large negative Gibbs

  18. Multivariate return periods of sea storms for coastal erosion risk assessment

    Directory of Open Access Journals (Sweden)

    S. Corbella

    2012-08-01

    Full Text Available The erosion of a beach depends on various storm characteristics. Ideally, the risk associated with a storm would be described by a single multivariate return period that is also representative of the erosion risk, i.e. a 100 yr multivariate storm return period would cause a 100 yr erosion return period. Unfortunately, a specific probability level may be associated with numerous combinations of storm characteristics. These combinations, despite having the same multivariate probability, may cause very different erosion outcomes. This paper explores this ambiguity problem in the context of copula based multivariate return periods and using a case study at Durban on the east coast of South Africa. Simulations were used to correlate multivariate return periods of historical events to return periods of estimated storm induced erosion volumes. In addition, the relationship of the most-likely design event (Salvadori et al., 2011 to coastal erosion was investigated. It was found that the multivariate return periods for wave height and duration had the highest correlation to erosion return periods. The most-likely design event was found to be an inadequate design method in its current form. We explore the inclusion of conditions based on the physical realizability of wave events and the use of multivariate linear regression to relate storm parameters to erosion computed from a process based model. Establishing a link between storm statistics and erosion consequences can resolve the ambiguity between multivariate storm return periods and associated erosion return periods.

  19. Erosive and Mechanical Tooth Wear in Viking Age Icelanders.

    Science.gov (United States)

    Richter, Svend; Eliasson, Sigfus Thor

    2017-08-29

    (1) Background: The importance of the Icelandic Sagas as a source of information about diet habits in medieval Iceland, and possibly other Nordic countries, is obvious. Extensive tooth wear in archaeological material worldwide has revealed that the main cause of this wear is believed to have been a coarse diet. Near the volcano Hekla, 66 skeletons dated from before 1104 were excavated, and 49 skulls could be evaluated for tooth wear. The purpose of this study was to determine the main causes of tooth wear in light of diet and beverage consumption described in the Sagas; (2) Materials and methods: Two methods were used to evaluate tooth wear and seven for age estimation; (3) Results: Extensive tooth wear was seen in all of the groups, increasing with age. The first molars had the highest score, with no difference between sexes. These had all the similarities seen in wear from a coarse diet, but also presented with characteristics that are seen in erosion in modern Icelanders, through consuming excessive amounts of soft drinks. According to the Sagas, acidic whey was a daily drink and was used for the preservation of food in Iceland, until fairly recently; (4) Conclusions: It is postulated that the consumption of acidic drinks and food, in addition to a coarse and rough diet, played a significant role in the dental wear seen in ancient Icelanders.

  20. Modeling soil erosion and transport on forest landscape

    Science.gov (United States)

    Ge Sun; Steven G McNulty

    1998-01-01

    Century-long studies on the impacts of forest management in North America suggest sediment can cause major reduction on stream water quality. Soil erosion patterns in forest watersheds are patchy and heterogeneous. Therefore, patterns of soil erosion are difficult to model and predict. The objective of this study is to develop a user friendly management tool for land...

  1. Laser investigation of the non-uniformity of fluorescent species in dental enamel

    Science.gov (United States)

    Tran, Stephanie U.; Ridge, Jeremy S.; Nelson, Leonard Y.; Seibel, Eric J.

    In the present study, artificial type I and type II erosions were created on dental specimen using acetic acid and EDTA respectively. Specimens were prepared by etching extracted teeth samples in acid to varying degrees, after which the absolute fluorescence intensity ratio of the etched enamel relative to sound enamel was recorded for each specimen using 405 and 532 nm laser excitation. Results showed differences in the fluorescence ratio of etched to sound enamel for type I and II erosions. These findings suggest a non-uniform distribution of fluorescent species in the interprismatic region as compared to the prismatic region.

  2. Using REE tracers to measure sheet erosion changing to rill erosion

    International Nuclear Information System (INIS)

    Liu Puling; Xue Yazhou; Song Wei; Wang Mingyi; Ju Tongjun

    2004-01-01

    Rare Earth Elements (REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different rare earth elements of different soil depth across a slope in an indoor plot, two simulated rainfalls were applied to study the change of erosion type and the rill erosion process. The results indicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happens after rill erosion appears. Accumulated sheet and rill erosion amounts increase with the rainfalls time. The percentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of the rainfalls, the total rill erosion amounts are 4-5 times more than sheet erosion. In this paper, a new REE tracer method was used to quantitatively distinguish sheet and rill erosion amounts. The new REE tracer method should be useful to future studying of erosion processes on slope lands. (authors)

  3. Child dental anxiety, parental rearing style and dental history reported by parents.

    Science.gov (United States)

    Krikken, J B; Vanwijk, A J; Tencate, J M; Veerkamp, J S

    2013-12-01

    To examine the relationship between self-reported parental rearing style, parent's assessment of their child's dental anxiety and the dental history of children. Parents of primary school children were asked to complete questionnaires about their parenting style, using four different questionnaires. Parents also completed the Child Fear Survey Schedule Dental Subscale (CFSS-DS) on behalf of their child and a questionnaire about the dental history of their child. 454 interview forms were available for analysis. Minor associations were found between dental anxiety and parenting style. Anxious parents were more permissive and less restrictive in their parenting style. Parents of children who did not visit their dentist for regular check-ups reported more laxness and less restrictiveness. Children who had a cavity at the time of investigation, children who had suffered from toothache in the past and children who did not have a nice and friendly dentist reported more dental anxiety. No clear associations between parenting style and dental anxiety were found. Known causes of dental anxiety were confirmed.

  4. Erosion protection conferred by whole human saliva, dialysed saliva, and artificial saliva

    Science.gov (United States)

    Baumann, T.; Kozik, J.; Lussi, A.; Carvalho, T. S.

    2016-10-01

    During dental erosion, tooth minerals are dissolved, leading to a softening of the surface and consequently to irreversible surface loss. Components from human saliva form a pellicle on the tooth surface, providing some protection against erosion. To assess the effect of different components and compositions of saliva on the protective potential of the pellicle against enamel erosion, we prepared four different kinds of saliva: human whole stimulated saliva (HS), artificial saliva containing only ions (AS), human saliva dialysed against artificial saliva, containing salivary proteins and ions (HS/AS), and human saliva dialysed against deionised water, containing only salivary proteins but no ions (HS/DW). Enamel specimens underwent four cycles of immersion in either HS, AS, HS/AS, HS/DW, or a humid chamber (Ctrl), followed by erosion with citric acid. During the cycling process, the surface hardness and the calcium released from the surface of the specimens were measured. The different kinds of saliva provided different levels of protection, HS/DW exhibiting significantly better protection than all the other groups (p < 0.0001). Different components of saliva, therefore, have different effects on the protective properties of the pellicle and the right proportions of these components in saliva are critical for the ability to form a protective pellicle.

  5. Inherited epidermolysis bullosa: an update and suggested dental care considerations.

    Science.gov (United States)

    Feijoo, Javier F; Bugallo, Juan; Limeres, Jacobo; Peñarrocha, David; Peñarrocha, Miguel; Diz, Pedro

    2011-09-01

    Epidermolysis bullosa (EB) is a skin disease characterized by epithelial fragility that leads to blistering and erosion of the skin and mucosae. The authors conducted a literature review to provide an update on oral manifestations and dental care of patients with EB. Literature Search. The authors reviewed the dental literature on EB in relation to clinical findings and provision of dental care. They searched textbooks and three databases: MEDLINE, Cochrane Library and Embase. The authors did not impose any date or publication status restrictions. They searched all databases up to August 2010. The literature review revealed that four major groups and 32 subtypes of EB can be distinguished on the basis of the ultrastructural characteristics of skin cleavage, genetic mode of transmission and clinical phenotype. Oral manifestations differ in frequency and severity according to the disease subtype, but the most common are bullae, which leave painful ulcers on rupture, followed by scarring and tissue contraction. Although good oral health status is essential to maintaining oral function, dental treatment can induce new lesions and be hindered by the sequelae of existing lesions. Dental treatment in patients with EB requires a multidisciplinary approach. Dental procedures must be minimally traumatic, and the effectiveness of treatment is determined mainly by the patient's general health, cooperation in the dental office and at home, oral hygiene and diet.

  6. Erosion-corrosion synergistics in the low erosion regime

    International Nuclear Information System (INIS)

    Corey, R.G.; Sethi, V.K.

    1986-01-01

    Many engineering alloys display good high temperature corrosion resistance. However, when they are used in corrosive environments where they are subjected to erosion also, the corrosion resistance has been adversely affected. The phenomenon known as erosion-corrosion is complex and requires detailed investigation of how the erosion and corrosion kinetics interact and compete. At the Kentucky Center for Energy Research Laboratory, an erosion-corrosion tester was used to perform erosion-oxidation tests on 2 1/4 Cr-1 Mo steel at 500-600 0 C using alumina abrasive at low velocities. The erosion-oxidation rate data and morphology of exposed surfaces are consistent with oxide chipping and fracturing being the mode of material loss

  7. Soil erosion rates caused by wind and saltating sand stresses in a wind tunnel

    International Nuclear Information System (INIS)

    Ligotke, M.W.

    1993-02-01

    Wind erosion tests were performed in a wind tunnel in support of the development of long-term protective barriers to cap stabilized waste sites at the Hanford Site. Controlled wind and saltating sand erosive stresses were applied to physical models of barrier surface layers to simulate worst-case eolian erosive stresses. The goal of these tests was to provide information useful to the design and evaluation of the surface layer composition of an arid-region waste site barrier concept that incorporates a deep fine-soil reservoir. A surface layer composition is needed that will form an armor resistant to eolian erosion during periods of extreme dry climatic conditions, especially when such conditions result in the elimination or reduction of vegetation by water deprivation or wildfire. Because of the life span required of Hanford waste barriers, it is important that additional work follow these wind tunnel studies. A modeling effort is planned to aid the interpretation of test results with respect to the suitability of pea gravel to protect the finite-soil reservoir during long periods of climatic stress. It is additionally recommended that wind tunnel tests be continued and field data be obtained at prototype or actual barrier sites. Results wig contribute to barrier design efforts and provide confidence in the design of long-term waste site caps for and regions

  8. Biocorrosion vs. erosion: the 21st century and a time to change.

    Science.gov (United States)

    Grippo, John O

    2012-02-01

    The author's objective is to precisely define the term "erosion" as a physical mechanism and to establish the mechanism of biocorrosion in the lexicon of dental terms. Using the prefix "bio" before corrosion differentiates it from corrosion, because it designates the chemical, biochemical, and electrochemical actions on enamel and dentin. Biocorrosion encompasses endogenous and exogenous acidic and proteolytic chemical degradation of enamel and dentin, as well as the piezoelectric electrochemical action on the collagen in dentin.

  9. Cause Analysis of Flow Accelerated Corrosion and Erosion-Corrosion Cases in Korea Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. S.; Lee, S. H. [Korea Hydro and Nuclear Power Co., Ltd., Gyeongju (Korea, Republic of); Hwang, K. M. [KEPCO Engineering and Construction Company, Gimcheon (Korea, Republic of)

    2016-08-15

    Significant piping wall thinning caused by Flow-Accelerated Corrosion (FAC) and Erosion-Corrosion (EC) continues to occur, even after the Mihama Power Station unit 3 secondary pipe rupture in 2004, in which workers were seriously injured or died. Nuclear power plants in many countries have experienced FAC and EC-related cases in steam cycle piping systems. Korea has also experienced piping wall thinning cases including thinning in the downstream straight pipe of a check valve in a feedwater pump line, the downstream elbow of a control valve in a feedwater flow control line, and failure of the straight pipe downstream of an orifice in an auxiliary steam return line. Cause analyses were performed by reviewing thickness data using Ultrasonic Techniques (UT) and, Scanning Electron Microscope (SEM) images for the failed pipe, and numerical simulation results for FAC and EC cases in Korea Nuclear Power Plants. It was concluded that the main cause of wall thinning for the downstream pipe of a check valve is FAC caused by water vortex flow due to the internal flow shape of a check valve, the main cause of wall thinning for the downstream elbow of a control valve is FAC caused by a thickness difference with the upstream pipe, and the main cause of wall thinning for the downstream pipe of an orifice is FAC and EC caused by liquid droplets and vortex flow. In order to investigate more cases, additional analyses were performed with the review of a lot of thickness data for inspected pipes. The results showed that pipe wall thinning was also affected by the operating condition of upstream equipment. Management of FAC and EC based on these cases will focus on the downstream piping of abnormal or unusual operated equipment.

  10. Prevalence, causes, and correlates of traumatic dental injuries among seven-to-twelve-year-old school children in Dera Bassi

    Directory of Open Access Journals (Sweden)

    Rohini Dua

    2012-01-01

    Full Text Available Aim : The paper aims to present a study conducted in Dera Bassi, Mohali, India. The purpose of the study was to ascertain the prevalence of traumatic dental injuries (TDI in children of age group 7-12 years in private schools in Gulabgarh village. Material & Method : Age & sex distribution, etiological factors, risk factors and cause of injury were the parameters taken into consideration. The data collected was processed and analyzed using the SPSS statistical software program. Results : The overall prevalence of dental trauma was 14.5%, amongst the 880 subjects examined, out of which, 63.2% males and 36.4% females were found to be affected. The maxillary central incisor was found to be most commonly affected tooth (43.8%. The most common cause of injury reported was fall during playing (37.5%. Conclusion : Enamel fracture was most prevalent (50%. No risk factor was significantly higher than others; however children with Angle′s class II div 1 malocclusion exhibited greater risk factor for traumatic injuries.

  11. The behaviour of composites, glass ionomers and compomers in erosive conditions – in vitro study

    Directory of Open Access Journals (Sweden)

    Borş Andreea

    2014-10-01

    Full Text Available Objective: The aim of this in vitro study was to evaluate the influence of erosive conditions on the wear resistance of aesthetic direct restorative materials. Methods: Six dental filling materials were tested: two composites (Filtek Z550 and X-tra fil, two compomers (Dyract Extra and Twinky Star and two glass ionomers (Ketac Molar and Fuji II LC. Twenty disks (10mm×2mm of each material were prepared (n=120 and kept in artificial saliva at 37˚C for 24 hours. Specimens were cycled in acidic soft drink (Coca-Cola 5×/day, for 5’, over 30 days. Initial surface roughness ISR (Ra-μm and final surface roughness FSR were measured using a profilometer. The wear rate was calculated as difference of final minus the initial roughness (ΔSR=FSR-ISR. For statistical analysis t-test and one-way ANOVA test were used by GraphPad Prism version 5.03 statistical software. The level of significance was set at p<0.05. Results: The erosive wear rates (mean±SD, μm after exposure to acidic beverage were: 0.30±0.03 (Ketac Molar, 0.28±0.04 (Fuji II LC, 0.27±0.00 (Filtek Z550, 0.23±0.01 (X-tra fil, 0.20±0.00 (Twinky Star and 0.14±0.01 Dyract Extra, respectively. There were significant differences between the tested materials (p<0.05. Conclusions: Dental filling materials had different behaviour under the same erosive condition, however all investigated aesthetic restorative materials showed surface degradation. These findings suggest that erosive wear resistance of tooth coloured restoratives could influence their longevity in intraoral acidic conditions. Acknowledgements: The study was supported by the Internal Research Grant no. 5/30.01.2013 of the University of Medicine and Pharmacy of Tirgu Mureş.

  12. Erosive Wear of Inconel 625 Alloy Coatings Deposited by CMT Method

    Directory of Open Access Journals (Sweden)

    Solecka M.

    2016-06-01

    Full Text Available The article presents the investigation results concerning the determination of the characteristics of erosive wear caused by the impact of Al2O3 solid particles on the surface of Inconel 625 alloy after plastic working and the same material after weld cladding process using the CMT method. Erosion wear tests were performed at two temperatures: 20°C and 650°C. The erosion tests were conducted using the standard ASTM G76. A jet with a specified abrasive waight was directed to the surface of the tested material at an α impingement angle varied in the range of 30-90° at a velocity imparted to the abrasive by the medium, which was compressed air. The eroded surface was examined using a scanning electron microscope (SEM, while the depths of craters caused by the erosion tests were measured with an optical profilometer. The predominant mechanisms of the formation of mass losses during solid particle erosion were microcutting and microfissuring.

  13. Diagnosis and treatment of abnormal dental pain.

    Science.gov (United States)

    Fukuda, Ken-Ichi

    2016-03-01

    Most dental pain is caused by an organic problem such as dental caries, periodontitis, pulpitis, or trauma. Diagnosis and treatment of these symptoms are relatively straightforward. However, patients often also complain of abnormal dental pain that has a non-dental origin, whose diagnosis is challenging. Such abnormal dental pain can be categorized on the basis of its cause as referred pain, neuromodulatory pain, and neuropathic pain. When it is difficult to diagnose a patient's dental pain, these potential alternate causes should be considered. In this clinical review, we have presented a case of referred pain from the digastric muscle (Patient 1), of pulpectomized (Patient 2), and of pulpectomized pain (Patient 3) to illustrate referred, neuromodulatory, and neuropathic pain, respectively. The Patient 1 was advised muscle stretching and gentle massage of the trigger points, as well as pain relief using a nonsteroidal anti-inflammatory and the tricyclic antidepressant amitriptyline. The pain in Patient 2 was relieved completely by the tricyclic antidepressant amitriptyline. In Patient 3, the pain was controlled using either a continuous drip infusion of adenosine triphosphate or intravenous Mg2+ and lidocaine administered every 2 weeks. In each case of abnormal dental pain, the patient's diagnostic chart was used (Fig.2 and 3). Pain was satisfactorily relieved in all cases.

  14. Dental Treatment As A Cause Of Anxiety [o Tratamento Odontológico Como Gerador De Ansiedade

    OpenAIRE

    Possobon R. de F.; Carrascoza K.C.; de Moraes A.B.A.; Costa Jr. A.L.

    2007-01-01

    Dental treatment causes anxiety in patients and professionals. In the case of patients, the clinical aspects, mainly invasive factors, such as local anesthesia, and, in the case of professionals, their behavior may produce anxiety with their evasive answers. The need to deal with the patient's anxiety requires complex procedures of the dentists. Coupled to the dentist's own anxiety for technical preciseness and permanent clinical knowledge acquisitions, the dentist's routine turns into a phys...

  15. In vitro reduction of dental erosion by low-concentration TiF4 solutions

    NARCIS (Netherlands)

    Vieira, A.M.; Ruben, J.L.; Bronkhorst, E.M.; Huysmans, M.C.D.N.J.M.

    2011-01-01

    The aims of this study were to compare daily versus single applications of low-concentration TiF(4) solutions for reduction of enamel erosion and to evaluate the enamel surface loss due to application of these solutions. Sixty bovine enamel samples were randomly divided into 2 groups: single versus

  16. In vitro Reduction of Dental Erosion by Low-Concentration TiF4 Solutions

    NARCIS (Netherlands)

    Vieira, A. M.; Ruben, J. L.; Bronkhorst, E. M.; Huysmans, M. C. D. N. J. M.

    2011-01-01

    The aims of this study were to compare daily versus single applications of low-concentration TiF4 solutions for reduction of enamel erosion and to evaluate the enamel surface loss due to application of these solutions. Sixty bovine enamel samples were randomly divided into 2 groups: single versus

  17. High proportions of Staphylococcus epidermidis in dental caries harbor multiple classes of antibiotics resistance, significantly increase inflammatory interleukins in dental pulps.

    Science.gov (United States)

    Devang Divakar, Darshan; Muzaheed; Aldeyab, Sultan Salem; Alfawaz, Sara A; AlKheraif, Abdulaziz Abdullah; Ahmed Khan, Aftab

    2017-08-01

    Staphylococcus epidermidis is one of most prevalent in dental caries or dental pulp which has the capability of horizontal genetic transfer between different bacterial species in the oropharynx, suggesting that it may evolve with the dissemination of resistant determinants, This study was performed to molecularly characterize and differentiate S. epidermidis isolated from dental caries and healthy individual. Also, two important cytokines in inflammation were assayed caused due to S. epidermidis of health and dental caries sources. Dental caries strains were more resistant with high MIC 50 and MIC 90 value. These isolates also showed the presence of mecA gene and another virulence gene i. e sea and seb comparatively more than healthy individual isolates. SCCmec types, III and IV was more prevalent in dental caries isolates where an as healthy individual was more non-typable. Additionally, the quantity of IL-1β and IL-8 caused due to dental caries isolates was seen more which indicate dental caries isolates are able to induce. This study showed that S. epidermidis a normal flora of oropharyngeal are more diverse to those strains which cause dental caries. S. epidermidis owns a prodigious genetic plasticity that permits to obtain, lose or regulate genetic elements that provide compensations to improve its colonization in the host. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Application and verification of cold air velocity technique for solving tube ash erosion problem in PC boilers

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Kisoo; Jeong, Kwon Seok [Korea Southern Power Corporation, Gimhae (Korea, Republic of)

    2012-06-15

    Fly ash erosion is a leading cause of boiler tube failure in PC boilers. Therefore, shields or baffle plates are installed in specific areas to mitigate fly ash erosion and prevent boiler tube failure. However, the tube failure problems caused by fly ash erosion cannot be eliminated with this solution alone, because each PC boiler has a different flue gas flow pattern and erosion can become severe in unexpected zones. This problem is caused by an asymmetric internal flow velocity and local growth of the flue gas velocity. For these reasons, clearly defining the flow pattern in PC boilers is important for solving the problem of tube failure caused by fly ash erosion. For this purpose, the cold air velocity technique (CAVT) can be applied to the fly ash erosion problem. In this study, CAVT was carried out on the Hadong 2 PC boiler and the feasibility of application of CAVT to conventional PC boilers was validated.

  19. Application and verification of cold air velocity technique for solving tube ash erosion problem in PC boilers

    International Nuclear Information System (INIS)

    Yoo, Kisoo; Jeong, Kwon Seok

    2012-01-01

    Fly ash erosion is a leading cause of boiler tube failure in PC boilers. Therefore, shields or baffle plates are installed in specific areas to mitigate fly ash erosion and prevent boiler tube failure. However, the tube failure problems caused by fly ash erosion cannot be eliminated with this solution alone, because each PC boiler has a different flue gas flow pattern and erosion can become severe in unexpected zones. This problem is caused by an asymmetric internal flow velocity and local growth of the flue gas velocity. For these reasons, clearly defining the flow pattern in PC boilers is important for solving the problem of tube failure caused by fly ash erosion. For this purpose, the cold air velocity technique (CAVT) can be applied to the fly ash erosion problem. In this study, CAVT was carried out on the Hadong 2 PC boiler and the feasibility of application of CAVT to conventional PC boilers was validated

  20. Rill erosion of mudstone slope-a case study of southern Taiwan

    Science.gov (United States)

    Yang, Ci-Jian; Lin, Jiun-chuan; Cheng, Yuan-Chang

    2014-05-01

    Soil erosion has been studied by many scientists for decades (Zingg, 1940; Meyer & Wischmeier, 1969; Foster, 1982; Luk, 1988) and many soil erosion prediction equations have already been developed, such as USLE, RUSLE. In spite of WEEP is based on hydrological physical model, all of the above models are restricted to predict concentrate flow. On the other hand, rill erosion is not understood completely. The amounts of rill erosion are always underestimated. Rill Erosion correlate closely to gradient (Cerda & Garcia-Fayos, 1997; Fox & Bryan, 1999; Fu,et al., 2011; Clarke & Rendell, 2006), slope length (Gabriel, 1999; Yair, 2004), particle distribution (Gabriel, 1999), proportion of clay (Luk,1977; Bryan2000), rainfall intensity (Römkens et al. 2001), and land use (Dotterweich, 2008). However, the effect of micromorphology of mud rock surface, such as mud-cracks, could be studied in more details. This research aims to simulate rill development by hydraulic flume to observe the morphological change caused by rill/erosion process. Mudstone specimens sampled from the mudstone area of Long-Chi, southern Taiwan. The results show that: (1) The erosion pattern of mudstone slope can be divided into four steps: (a) inter-rill erosion, ( b) rill erosion, (c) rill development, (d) slope failure. (2) Slopes with mud-cracks caused 125% soil loss than smooth slopes. (3) Mud-cracks affect spatial distribution of rill development (4) The sediment concentration decreased sharply in the beginning of experiments, however increased due to rill development. This paper demonstrated such a rill development. 1: Department of Geography, National Taiwan University. E-mail:maxpossibilism0929@gmail.com

  1. Hydro-abrasive erosion of hydraulic turbines caused by sediment - a century of research and development

    Science.gov (United States)

    Felix, D.; Albayrak, I.; Abgottspon, A.; Boes, R. M.

    2016-11-01

    Hydro-abrasive erosion of hydraulic turbines is an economically important issue due to maintenance costs and production losses, in particular at high- and medium-head run-of- river hydropower plants (HPPs) on sediment laden rivers. In this paper, research and development in this field over the last century are reviewed. Facilities for sediment exclusion, typically sand traps, as well as turbine design and materials have been improved considerably. Since the 1980s, hard-coatings have been applied on Francis and Pelton turbine parts of erosion-prone HPPs and became state-of-the-art. These measures have led to increased times between overhauls and smaller efficiency reductions. Analytical, laboratory and field investigations have contributed to a better processes understanding and quantification of sediment-related effects on turbines. More recently, progress has been made in numerical modelling of turbine erosion. To calibrate, validate and further develop prediction models, more measurements from both physical model tests in laboratories and real-scale data from HPPs are required. Significant improvements to mitigate hydro-abrasive erosion have been achieved so far and development is ongoing. A good collaboration between turbine manufacturers, HPP operators, measuring equipment suppliers, engineering consultants, and research institutes is required. This contributes to the energy- and cost-efficient use of the worldwide hydropower potential.

  2. A terminological matter: paragenesis, antigravitative erosion or antigravitational erosion ?

    Directory of Open Access Journals (Sweden)

    Pasini G.

    2009-07-01

    Full Text Available In the speleological literature three terms are utilized to designate the “ascending erosion”: paragenesis (= paragénésis, coined in1968, antigravitative erosion (= erosione antigravitativa, coined in 1966 and antigravitational erosion (wrong English translation ofthe Italian term erosione antigravitativa, utilized later on. The term paragenesis should be abandoned because of the priority of theterm erosione antigravitativa - on the ground of the “law of priority” – and because of its ambiguous etimology. On the other hand,the term antigravitational erosion should be forsaken in favour of the term antigravitative erosion, given the meaning that the termsgravitation and gravity have in Physics. Therefore, to designate the phenomenon of the “ascending erosion” there would be nothingleft but the term antigravitative erosion.The antigravitative erosion process and its recognizability are illustrated.Examples of caves with evident antigravitative erosion phenomena, developed in different karstifiable rocks and in several partsof the world, are given.It is recalled that the antigravitative erosion is a phenomenon well-known since 1942 and widely proven and supported, and that it isrelatively easy – in many cases - to recognize the antigravitative origin of karstic passages.It is stressed that the antigravitative erosion is an important phenomenon, exclusive of the karstic caves and unique in nature.

  3. Tooth wear

    OpenAIRE

    Tušek Ivan; Tušek Jasmina

    2014-01-01

    Tooth wear is the loss of dental hard tissue that was not caused by decay and represents a common clinical problem of modern man. In the etiology of dental hard tissue lesions there are three dominant mechanisms that may act synergistically or separately:friction (friction), which is caused by abrasion of exogenous, or attrition of endogenous origin, chemical dissolution of dental hard tissues caused by erosion, occlusal stress created by compression and flexion and tension that leads to toot...

  4. Multifunctional poly(alkyl methacrylate) films for dental care

    International Nuclear Information System (INIS)

    Nielsen, Birthe V; Nevell, Thomas G; Barbu, Eugen; Smith, James R; Tsibouklis, John; Rees, Gareth D

    2011-01-01

    Towards the evaluation of non-permanent dental coatings for their capacity to impart dental-care benefits, thin films of a homologous series of comb-like poly(alkyl methacrylate)s (ethyl to octadecyl) have been deposited, from aqueous latex formulations, onto dentally relevant substrates. AFM studies have shown that the thickness (40-300 nm) and surface roughness (8-12 nm) of coherent polymer films are influenced by the degree of polymerization and by the length of the pendant chain. Of the polymers under consideration, poly(butyl methacrylate) formed a close-packed film that conferred to dental substrates a high degree of inhibition to acid-mediated erosion (about 27%), as evaluated by released-phosphate determinations. The potential utility of the coatings to act as anti-sensitivity barriers has been evaluated by determining the hydraulic conductance of coated bovine-dentine substrates; single treatments of dentine discs with poly(butyl methacrylate) or with poly(ethyl methacrylate) effected mean respective reductions in fluid flow of about 23% with respect to water-treated controls; repeated applications of the poly(butyl methacrylate) latex led to mean reductions in fluid flow of about 80%. Chromometric measurements have shown that pellicle-coated hydroxyapatite discs treated with poly(butyl methacrylate), poly(hexyl methacrylate) or poly(lauryl methacrylate) exhibit significant resistance to staining by food chromogens.

  5. Multifunctional poly(alkyl methacrylate) films for dental care

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Birthe V; Nevell, Thomas G; Barbu, Eugen; Smith, James R; Tsibouklis, John [School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, Hampshire, PO1 2DT (United Kingdom); Rees, Gareth D [GlaxoSmithKline R and D, St George' s Avenue, Weybridge, Surrey, KT13 0DE (United Kingdom)

    2011-02-15

    Towards the evaluation of non-permanent dental coatings for their capacity to impart dental-care benefits, thin films of a homologous series of comb-like poly(alkyl methacrylate)s (ethyl to octadecyl) have been deposited, from aqueous latex formulations, onto dentally relevant substrates. AFM studies have shown that the thickness (40-300 nm) and surface roughness (8-12 nm) of coherent polymer films are influenced by the degree of polymerization and by the length of the pendant chain. Of the polymers under consideration, poly(butyl methacrylate) formed a close-packed film that conferred to dental substrates a high degree of inhibition to acid-mediated erosion (about 27%), as evaluated by released-phosphate determinations. The potential utility of the coatings to act as anti-sensitivity barriers has been evaluated by determining the hydraulic conductance of coated bovine-dentine substrates; single treatments of dentine discs with poly(butyl methacrylate) or with poly(ethyl methacrylate) effected mean respective reductions in fluid flow of about 23% with respect to water-treated controls; repeated applications of the poly(butyl methacrylate) latex led to mean reductions in fluid flow of about 80%. Chromometric measurements have shown that pellicle-coated hydroxyapatite discs treated with poly(butyl methacrylate), poly(hexyl methacrylate) or poly(lauryl methacrylate) exhibit significant resistance to staining by food chromogens.

  6. Mechanisms of erosion of atherosclerotic plaques.

    Science.gov (United States)

    Quillard, Thibaut; Franck, Grégory; Mawson, Thomas; Folco, Eduardo; Libby, Peter

    2017-10-01

    The present review explores the mechanisms of superficial intimal erosion, a common cause of thrombotic complications of atherosclerosis. Human coronary artery atheroma that give rise to thrombosis because of erosion differ diametrically from those associated with fibrous cap rupture. Eroded lesions characteristically contain few inflammatory cells, abundant extracellular matrix, and neutrophil extracellular traps (NETs). Innate immune mechanisms such as engagement of Toll-like receptor 2 (TLR2) on cultured endothelial cells can impair their viability, attachment, and ability to recover a wound. Hyaluronan fragments may serve as endogenous TLR2 ligands. Mouse experiments demonstrate that flow disturbance in arteries with neointimas tailored to resemble features of human eroded plaques disturbs endothelial cell barrier function, impairs endothelial cell viability, recruits neutrophils, and provokes endothelial cells desquamation, NET formation, and thrombosis in a TLR2-dependent manner. Mechanisms of erosion have received much less attention than those that provoke plaque rupture. Intensive statin treatment changes the characteristic of plaques that render them less susceptible to rupture. Thus, erosion may contribute importantly to the current residual burden of risk. Understanding the mechanisms of erosion may inform the development and deployment of novel therapies to combat the remaining atherothrombotic risk in the statin era.

  7. Child′s dental fear: Cause related factors and the influence of audiovisual modeling

    Directory of Open Access Journals (Sweden)

    Jayanthi Mungara

    2013-01-01

    Full Text Available Background: Delivery of effective dental treatment to a child patient requires thorough knowledge to recognize dental fear and its management by the application of behavioral management techniques. Children′s Fear Survey Schedule - Dental Subscale (CFSS-DS helps in identification of specific stimuli which provoke fear in children with regard to dental situation. Audiovisual modeling can be successfully used in pediatric dental practice. Aim: To assess the degree of fear provoked by various stimuli in the dental office and to evaluate the effect of audiovisual modeling on dental fear of children using CFSS-DS. Materials and Methods: Ninety children were divided equally into experimental (group I and control (group II groups and were assessed in two visits for their degree of fear and the effect of audiovisual modeling, with the help of CFSS-DS. Results: The most fear-provoking stimulus for children was injection and the least was to open the mouth and having somebody look at them. There was no statistically significant difference in the overall mean CFSS-DS scores between the two groups during the initial session (P > 0.05. However, in the final session, a statistically significant difference was observed in the overall mean fear scores between the groups (P < 0.01. Significant improvement was seen in group I, while no significant change was noted in case of group II. Conclusion: Audiovisual modeling resulted in a significant reduction of overall fear as well as specific fear in relation to most of the items. A significant reduction of fear toward dentists, doctors in general, injections, being looked at, the sight, sounds, and act of the dentist drilling, and having the nurse clean their teeth was observed.

  8. Effect of green tea as a protective measure against dental erosion in coronary dentine

    Directory of Open Access Journals (Sweden)

    Maria Denise Rodrigues DE MORAES

    2016-01-01

    Full Text Available Abstract The aim of this study was to evaluate the effect of green tea as a protective measure on eroded dentin. Disks of human coronary dentin were selected based on surface hardness and randomly assigned to 3 groups (n = 10: DW - distilled water, CHX - 0.2% chlorhexidine digluconate, and GT - green tea. The disks were allowed to acquire pellicle for 2 hours and were then subjected to 3 cycles per day of demineralization (C6H8O7 0.05 M, pH 3.75, 60 s, treatment (DW or CHX or GT, 5 min and remineralization (artificial saliva, 60 min over a period of 3 days. Changes in the dentin were determined by loss of surface hardness (%SHL and mechanical profilometry analysis at the end of each day. Data were analyzed by two-way ANOVA followed by Tukey’s test for %SHL and profilometry (p 0.05. A significant difference was observed between DW and GT treatments for wear and roughness measurements (p < 0.05. The green tea extract solution was able to reduce the wear and roughness caused by dentin erosion under the conditions of this study.

  9. General dental practitioner's views on dental general anaesthesia services.

    Science.gov (United States)

    Threlfall, A G; King, D; Milsom, K M; Blinkhom, A S; Tickle, M

    2007-06-01

    Policy has recently changed on provision of dental general anaesthetic services in England. The aim of this study was to investigate general dental practitioners' views about dental general anaesthetics, the reduction in its availability and the impact on care of children with toothache. Qualitative study using semi-structured interviews and clinical case scenarios. General dental practitioners providing NHS services in the North West of England. 93 general dental practitioners were interviewed and 91 answered a clinical case scenario about the care they would provide for a 7-year-old child with multiple decayed teeth presenting with toothache. Scenario responses showed variation; 8% would immediately refer for general anaesthesia, 25% would initially prescribe antibiotics, but the majority would attempt to either restore or extract the tooth causing pain. Interview responses also demonstrated variation in care, however most dentists agree general anaesthesia has a role for nervous children but only refer as a last resort. The responses indicated an increase in inequalities, and that access to services did not match population needs, leaving some children waiting in pain. Most general dental practitioners support moving dental general anaesthesia into hospitals but some believe that it has widened health inequalities and there is also a problem associated with variation in treatment provision. Additional general anaesthetic services in some areas with high levels of tooth decay are needed and evidence based guidelines about caring for children with toothache are required.

  10. Ash particle erosion on steam boiler convective section

    Energy Technology Data Exchange (ETDEWEB)

    Meuronen, V

    1998-12-31

    In this study, equations for the calculation of erosion wear caused by ash particles on convective heat exchanger tubes of steam boilers are presented. A new, three-dimensional test arrangement was used in the testing of the erosion wear of convective heat exchanger tubes of steam boilers. When using the sleeve-method, three different tube materials and three tube constructions could be tested. New results were obtained from the analyses. The main mechanisms of erosion wear phenomena and erosion wear as a function of collision conditions and material properties have been studied. Properties of fossil fuels have also been presented. When burning solid fuels, such as pulverized coal and peat in steam boilers, most of the ash is entrained by the flue gas in the furnace. In bubbling and circulating fluidized bed boilers, particle concentration in the flue gas is high because of bed material entrained in the flue gas. Hard particles, such as sharp edged quartz crystals, cause erosion wear when colliding on convective heat exchanger tubes and on the rear wall of the steam boiler. The most important ways to reduce erosion wear in steam boilers is to keep the velocity of the flue gas moderate and prevent channelling of the ash flow in a certain part of the cross section of the flue gas channel, especially near the back wall. One can do this by constructing the boiler with the following components. Screen plates can be used to make the velocity and ash flow distributions more even at the cross-section of the channel. Shield plates and plate type constructions in superheaters can also be used. Erosion testing was conducted with three types of tube constructions: a one tube row, an in- line tube bank with six tube rows, and a staggered tube bark with six tube rows. Three flow velocities and two particle concentrations were used in the tests, which were carried out at room temperature. Three particle materials were used: quartz, coal ash and peat ash particles. Mass loss

  11. Evaluation of human dental loss caused by carbamide peroxide bleacher compared with phosphoric acid conditioning - radioactive method

    International Nuclear Information System (INIS)

    Adachi, Eduardo Makoto; Yousseff, Michel Nicolau; Saiki, Mitiko

    2002-01-01

    The radiometric method was applied to the evaluation of dental loss caused by carbamide peroxide when it is applied on the surface layers of enamel and dentin tissues. Also the dental loss caused by the etching with 37% phosphoric acid procedure used in aesthetic restoration was assessed for comparison with those results obtained. The tooth samples irradiated with a P standard in a thermal neutron flux of the nuclear reactor were placed in contact with 10% carbamide peroxide or with 37% phosphoric acid solution. The radioactivity of 32 P transferred from the radioactive teeth to the bleaching gel or to etching acid was measured using a Geiger Muller detector to calculate the mass of P removed in this treatment and losses were calculated after obtaining their P concentrations. Results obtained indicated that enamel and dentin exposed to carbamide peroxide bleaching agent lose phosphorus. The extent of enamel loss was smaller than that obtained for dentin. In the case of acid etching, there was no difference between the results obtained for enamel and dentin loss. Also the dentin loss obtained after a treatment of 30 applications of 10% carbamide peroxide was the same magnitude of that one application of 37% phosphoric acid. (author)

  12. Comparison Between Bandage Contact Lenses and Pressure Patching on the Erosion Area and Pain Scale in Patients With Corneal Erosion.

    Science.gov (United States)

    Triharpini, Ni Nyoman; Gede Jayanegara, I Wayan; Handayani, Ariesanti Tri; Widiana, I Gde Raka

    2015-01-01

    Corneal erosion is common in eye emergency cases. Extensive corneal erosions result in severe pain and prolonged healing time. This study aimed to compare bandage contact lenses with pressure patching in terms of reducing the size of the erosion area, pain scale in patients with corneal erosion and its complications. A randomized open-label clinical trial was conducted. Subjects with mechanical corneal erosion were selected to use either bandage contact lenses or pressure patching. All subjects received antibiotic eye drops and 0.5% tropicamide eye drops. Evaluations were done 24 and 72 hours after treatment. The size of the corneal erosion area, pain scale, and complications were assessed. A total of 32 eyes (16 eyes in each group) were studied. The change in the size of the corneal erosion area was greater in the bandage contact lens group than in the pressure patching group, although there was no significant difference. In the bandage contact lens group, 56.25% of the eyes were healed at 24 hours and 43.75% were healed at 72 hours. In the pressure patching group, 62.50% were healed at 24 hours and 12.50% were healed at 72 hours. The change in pain scale was significantly greater in the bandage contact lens group than in the pressure patching group. No complications were found in both groups. Bandage contact lenses are an effective alternative to treating mechanical corneal erosion because of their effect in reducing pain without causing any complications.

  13. Quantifying thresholds for significant dune erosion along the Sefton Coast, Northwest England

    Science.gov (United States)

    Esteves, Luciana S.; Brown, Jennifer M.; Williams, Jon J.; Lymbery, Graham

    2012-03-01

    Field and model hindcast data are used to establish a critical dune erosion threshold for the Sefton Coast (NW England). Events are classified as causing significant erosion if they result in: (a) a mean dune retreat along the entire study area of > 2 m; (b) a dune retreat of ≥ 5 m along a coastal segment ≥ 2 km in length; and (c) an eroded area ≥ 20,000 m2. For the period 1996 to 2008, individual storms were characterised using hindcast results from a POLCOMS-WAM model and measured data from the Liverpool Bay Coastal Observatory. Results show that combined extreme surge levels (> 1.5 m) and wave heights (> 4 m), or tidal water levels above 9.0 m Chart Datum (CD), do not always result in significant dune erosion. Evidence suggests that erosion is more likely to occur when wave heights are > 2.6 m, peak water level is > 10.2 m CD at Liverpool and when consecutive tidal cycles provide 10 h or more of water levels above 9.4 m CD. However, lower water levels and wave heights, and shorter events of sustained water levels, can cause significant erosion in the summer. While the return period for events giving rise to the most severe erosion in the winter is > 50 years, significant erosion in the summer can be caused by events with return periods dune toe elevation c. 30 cm. Although the study shows it might be possible to characterise objectively storm events based on oceanographic conditions, the resultant morphological change at the coast is demonstrated to depend on the time and duration of events, and on other variables which are not so easy to quantify. Further investigation is needed to understand the influence of alongshore and seasonal variability in beach/dune morphology in determining the response to the hydrodynamic and meteorological conditions causing significant erosion. Improved monitoring pre- and post-storm of changes in beach/dune morphology is required to develop reliable proxies that can be used to establish early warning systems to mitigate the

  14. Erosive potential of soft drinks on human enamel: An in vitro study

    Directory of Open Access Journals (Sweden)

    Yin-Lin Wang

    2014-11-01

    Conclusion: All tested soft drinks were found to be erosive. Soft drinks with high calcium contents have significantly lower erosive potential. Low pH value and high citrate content may cause more surface enamel loss. As the erosive time increased, the titratable acidity to pH 7 may be a predictor of the erosive potential for acidic soft drinks. The erosive potential of the soft drinks may be predicted based on the types of acid content, pH value, titratable acidity, and ion concentration.

  15. Erosion prediction for alpine slopes: a symbiosis of remote sensing and a physical based erosion model

    Science.gov (United States)

    Kaiser, Andreas; Neugirg, Fabian; Haas, Florian; Schindewolf, Marcus; Schmidt, Jürgen

    2014-05-01

    As rainfall simulations represent an established tool for quantifying soil detachment on cultivated area in lowlands and low mountain ranges, they are rarely used on steep slopes high mountain ranges. Still this terrain represents productive sediment sources of high morphodynamic. A quantitative differentiation between gravitationally and fluvially relocated material reveals a major challenge in understanding erosion on steep slopes: does solifluction as a result of melting in spring or heavy convective rainstorms during summer cause the essential erosion processes? This paper aims to answer this question by separating gravitational mass movement (solifluction, landslides, mudflow and needle ice) and runoff-induced detachment. First simulated rainstorm experiments are used to assess the sediment production on bare soil on a strongly inclined plot (1 m², 42°) in the northern limestone Alps. Throughout precipitation experiments runoff and related suspended sediments were quantified. In order to enlarge slope length virtually to around 20 m a runoff feeding device is additionally implemented. Soil physical parameters were derived from on-site sampling. The generated data is introduced to the physically based and catchment-scaled erosion model EROSION 3D to upscale plot size to small watershed conditions. Thus infiltration, runoff, detachment, transport and finally deposition can be predicted for single rainstorm events and storm sequences. Secondly, in order to separate gravitational mass movements and water erosion, a LiDAR and structure-from-motion based monitoring approach is carried out to produce high-resolution digital elevation models. A time series analysis of detachment and deposition from different points in time is implemented. Absolute volume losses are then compared to sediment losses calculated by the erosion model as the latter only generates data that is connected to water induced hillside erosion. This methodology will be applied in other watersheds

  16. The Mechanism behind Erosive Bursts in Porous Media

    Science.gov (United States)

    Jaeger, Robin; Mendoza, Miller; Herrmann, Hans

    2017-11-01

    We implemented a new model based on the Lattice Boltzmann method to simulate erosion and deposition in suspension flows through porous media. Using this model we show that the cause of erosive bursts in filtration experiments is the re-opening of clogged pores when the pressure difference between two opposite sites of the pore surpasses a certain threshold. We perform numerical simulations and find excellent agreement to experimental results when comparing shape and size distribution of pressure loss jumps, which are the direct result of erosive bursts. Furthermore, we find that erosive bursts only occur for pressure gradient thresholds within the range of two critical values, independent on how the flow is driven. We believe that our findings provide a better understanding of sudden sand production in oil wells and breakthrough in filtration. European Research Council (ERC) Advanced Grant 319968-FlowCCS.

  17. Solid particle erosion of polymers and composites

    Science.gov (United States)

    Friedrich, K.; Almajid, A. A.

    2014-05-01

    After a general introduction to the subject of solid particle erosion of polymers and composites, the presentation focusses more specifically on the behavior of unidirectional carbon fiber (CF) reinforced polyetheretherketone (PEEK) composites under such loadings, using different impact conditions and erodents. The data were analyzed on the basis of a newly defined specific erosive wear rate, allowing a better comparison of erosion data achieved under various testing conditions. Characteristic wear mechanisms of the CF/PEEK composites consisted of fiber fracture, matrix cutting and plastic matrix deformation, the relative contribution of which depended on the impingement angles and the CF orientation. The highest wear rates were measured for impingement angles between 45 and 60°. Using abrasion resistant neat polymer films (in this case PEEK or thermoplastic polyurethane (TPU) ones) on the surface of a harder substrate (e.g. a CF/PEEK composite plate) resulted in much lower specific erosive wear rates. The use of such polymeric films can be considered as a possible method to protect composite surfaces from damage caused by minor impacts and erosion. In fact, they are nowadays already successfully applied as protections for wind energy rotor blades.

  18. Experiment of cavitation erosion at the exit of a long orifice

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Yoshinori; Murase, Michio [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2002-09-01

    We performed experiments to clarify mechanism of cavitation erosion and to predict cavitation erosion rate at the exit of a long orifice equipped at the chemical and volume control system in a pressurized water reactor (PWR). In order to find this mechanism, we used a high speed video camera. As the result, we observed bubble collapses near the exit of the orifice when flow condition was oscillating. So the bubble collapses due to the oscillation might cause the first stage erosion at the exit of the orifice. Using the orifice which had the cone-shaped exit, we observed that bubbles collapsed near the exit and then they collapsed at the upstream like a chain reaction. So this bubble collapse mechanism could be explained as follows: shock wave was generated by the bubble collapse near the exit, then it propagated upwards, consequently it caused the bubble collapse at the upstream. And we predicted erosion rate by evaluating the effect of the velocity and comparing the erosion resistance between the test speciment (aluminum) and the plant material (stainless steel) by means of vibratory tests. We compared the predicted erosion rate with that of the average value estimated from plant investigation, then we examined the applicability of these method to the plant evaluations. (author)

  19. Numerical modelling of concentrated leak erosion during Hole Erosion Tests

    OpenAIRE

    Mercier, F.; Bonelli, S.; Golay, F.; Anselmet, F.; Philippe, P.; Borghi, R.

    2015-01-01

    This study focuses on the numerical modelling of concentrated leak erosion of a cohesive soil by a turbulent flow in axisymmetrical geometry, with application to the Hole Erosion Test (HET). The numerical model is based on adaptive remeshing of the water/soil interface to ensure accurate description of the mechanical phenomena occurring near the soil/water interface. The erosion law governing the interface motion is based on two erosion parameters: the critical shear stress and the erosion co...

  20. Erosion by rain in the western Congo

    International Nuclear Information System (INIS)

    Ploey, J. de

    1967-01-01

    Vast expanses of the western part of central and southern Africa are covered with uniform, sandy formations of the Kalahari type. The topography of these areas and their present morphological characteristics are mainly the result of erosion by rain. Information on the hydrology of the surface waters in these areas is fairly limited and is insufficient to permit any conclusions regarding the way in which erosion by rain takes place. To obtain a better understanding of these phenomena, the author devised a series of experiments based on the use of 46 Sc-labelled radioactive sand. These experiments began at the beginning of the 1964/65 rainy season and are continuing. The experimental plot corresponds to convex and rectilinear portions of a hillside with a slope varying between 0 and 12 degrees. The vegetation consists of grassy savannah of substeppe appearance and secondary forests. Series of labelled samples were placed successively on the surface of the experimental plot and the erosive effect of rain was determined by measuring the residual concentrations after rainfall. Some samples were placed below a shield so as to eliminate the effects of splash and reveal the part played by runoff. Radiographic films were used to study the dispersion of labelled particles in the surrounding area. This radiographic method made it possible to determine the scale of erosion by splash for different rainfall conditions. The erosion diagrams obtained from these experiments show the correlations that exist between the intensity and duration of the rainfall and the erosion of the soil. Examination of the erosion diagrams and the shielded samples and analysis of the radiographs showed that erosion by rain on Kalahari ground covered with substeppe savannah is caused mainly by splash erosion and by dispersed, intermittent runoff. Sheet wash plays no part if the slope is less than 12 degrees. (author) [fr

  1. Manufacturing issues which affect coating erosion performance in wind turbine blades

    Science.gov (United States)

    Cortés, E.; Sánchez, F.; Domenech, L.; Olivares, A.; Young, T. M.; O'Carroll, A.; Chinesta, F.

    2017-10-01

    Erosion damage, caused by repeated rain droplet impact on the leading edges of wind turbine blades, is a major cause for cost concern. Resin Infusion (RI) is used in wind energy blades where low weight and high mechanical performance materials are demanded. The surface coating plays a crucial role in the manufacturing and performance response. The Leading Edge coating is usually moulded, painted or sprayed onto the blade surface so adequate adhesion in the layers' characterization through the thickness is required for mechanical performance and durability reasons. In the current work, an investigation has been directed into the resulting rain erosion durability of the coating was undertaken through a combination of mass loss testing measurements with manufacturing processing parameter variations. The adhesion and erosion is affected by the shock wave caused by the collapsing water droplet on impact. The stress waves are transmitted to the substrate, so microestructural discontinuities in coating layers and interfaces play a key role on its degradation. Standard industrial systems are based on a multilayer system, with a high number of interfaces that tend to accelerate erosion by delamination. Analytical and numerical models are commonly used to relate lifetime prediction and to identify suitable coating and composite substrate combinations and their potential stress reduction on the interface. In this research, the input parameters for the appropriate definition of the Cohesive Zone Modelling (CZM) of the coating-substrate interface are outlined by means of Pull off testing and Peeling testing results. It allowed one to optimize manufacturing and coating process for blades into a knowledge-based guidance for leading edge coating material development. It was achieved by investigating the erosion degradation process using both numerical and laboratory techniques (Pull off, Peeling and Rain Erosion Testing in a whirling arm rain erosion test facility).

  2. An extreme wind erosion event of the fresh Eyjafjallajökull 2010 volcanic ash.

    Science.gov (United States)

    Arnalds, Olafur; Thorarinsdottir, Elin Fjola; Thorsson, Johann; Waldhauserova, Pavla Dagsson; Agustsdottir, Anna Maria

    2013-01-01

    Volcanic eruptions can generate widespread deposits of ash that are subsequently subjected to erosive forces which causes detrimental effects on ecosystems. We measured wind erosion of the freshly deposited Eyjafjallajökull ash at a field site the first summer after the 2010 eruption. Over 30 wind erosion events occurred (June-October) at wind speeds > 10 m s(-1) in each storm with gusts up to 38.7 m s(-1). Surface transport over one m wide transect (surface to 150 cm height) reached > 11,800 kg m(-1) during the most intense storm event with a rate of 1,440 kg m(-1) hr(-1) for about 6½ hrs. This storm is among the most extreme wind erosion events recorded on Earth. The Eyjafjallajökull wind erosion storms caused dust emissions extending several hundred km from the volcano affecting both air quality and ecosystems showing how wind erosion of freshly deposited ash prolongs impacts of volcanic eruptions.

  3. Effect of hard second-phase particles on the erosion resistance of model alloys

    International Nuclear Information System (INIS)

    Kosel, T.H.; Aptekar, S.S.

    1986-01-01

    The dependence of erosion rate on second phase volume fraction (SPVF) has been studied for Cu/Al/sub 2/O/sub 3/ and Cu/WC(W/sub 2/C) model alloys produced by pressing and sintering. The intention was to investigate the reasons for the poor contribution to erosion resistance made by large hard second phase particles (SPP) in other studies. The results show that for Cu/Al/sub 2/O/sub 3/ alloys, the erosion rate generally increased with SPVF, demonstrating a negative contribution to erosion resistance. This occurred despite the fact that the measured erosion rate of monolithic Al/sub 2/O/sub 3/ was lower by one to two orders of magnitude than that of the pure matrix. Changing from severe erosion with large erodent particles at high velocity to mild conditions with small erodent at low velocity caused a change from depression of the SPPs to protrusion from the surface, with some improvement of the relative erosion resistance compared to the pure matrix. For Cu/WC(W/sub 2/C) alloys, changing from severe to mild erosion conditions caused a change from an increase of erosion with SPVF to a decrease. The results are discussed in terms of the increased microfracture of the unsupported edges of the second phase particles compared to a flat single-phase surface. This edge is consistent with the results, and explains observations not predicted by existing theories for erosion of single-phase materials. A model is introduced which predicts a new averaging law for the erosion rate of a two-phase alloy in terms of erosion rates of its constituent phases

  4. STUDY OF GREAT EROSIONS: A PROPOSAL OF METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Raifran Abidimar de Castro

    2005-05-01

    Full Text Available The erosions, are urban or agricultural they, have much time worry the urban and agricultural population, the public power and the particular companies. This concern has stimulated the studies on this partner-ambient problem. Guodie (1990 apud Guerra e Mendonça,.2004, p.228 “they affirm that the erosion of ground is the main and more serious impact caused for the action human being on the environment. Impacts these that can enclose since the loss of patrimony until problems of ambient degradation and losses of lives human beings.”Guerra & Cunha (2003, p.337, they affirm that: "In the reality, so that the problem can be understood of global form, integrated, holistic, it must be taken in account the existing relations between the ambient degradation and the causing society from that, at the same time, it suffers the effect and it looks for to decide, it recoups and it reconstitutes the degraded areas". Therefore one of the urban problems that more contribute for the growth of erosionsis the occupation of inadequate areas.As it is known first attitude that must be had for a necessary study of erosions is to analyze the erosive processes that act in the same one. On this subject, Guerra & Mendonça (2004, p. 229 they affirm that: "Some factors are the ones that intervene on the erosive processes: kinetic energy of the water of rains, chemical and physical properties of ground, forms and declivity of the hillsides, vegetal covering and handling of the ground ".

  5. Metal of cavitation erosion of a hydrodynamic reactor

    Science.gov (United States)

    Zakirzakov, A. G.; Brand, A. E.; Petryakov, V. A.; Gordievskaya, E. F.

    2017-02-01

    Cavitation erosion is a major cause of the petroleum equipment hydraulic erosion, which leads to the metal weight loss of the equipment and its breakdown, which can be followed by the full stop of the plant or company work. The probability of the metal weight loss and equipment failure can be reduced by the use of special protective coatings or rivets, made of the sacrificial metals, the use of which significantly increases the service life and the production equipment reliability. The article investigates the cavitation erosion effect, occurred under the condition of the advanced hydrodynamic cavitation on the hydrodynamic cavitation reactor. This article presents the results of the experiments and recommendations for increasing the operational resource.

  6. Traumatic dental injuries and associated factors in permanent ...

    African Journals Online (AJOL)

    Background: Traumatic dental injuries in children are increasingly becoming a serious dental public health problem worldwide. Despite this fact, less attention has been directed to this problem compared to other common oral problems like dental caries. Aims: To determine the prevalence, causes and correlates of ...

  7. Wind Erosion Caused by Land Use Changes Significantly Reduces Ecosystem Carbon Storage and Carbon Sequestration Potentials in Grassland

    Science.gov (United States)

    Li, P.; Chi, Y. G.; Wang, J.; Liu, L.

    2017-12-01

    Wind erosion exerts a fundamental influence on the biotic and abiotic processes associated with ecosystem carbon (C) cycle. However, how wind erosion under different land use scenarios will affect ecosystem C balance and its capacity for future C sequestration are poorly quantified. Here, we established an experiment in a temperate steppe in Inner Mongolia, and simulated different intensity of land uses: control, 50% of aboveground vegetation removal (50R), 100% vegetation removal (100R) and tillage (TI). We monitored lateral and vertical carbon flux components and soil characteristics from 2013 to 2016. Our study reveals three key findings relating to the driving factors, the magnitude and consequence of wind erosion on ecosystem C balance: (1) Frequency of heavy wind exerts a fundamental control over the severity of soil erosion, and its interaction with precipitation and vegetation characteristics explained 69% variation in erosion intensity. (2) With increases in land use intensity, the lateral C flux induced by wind erosion increased rapidly, equivalent to 33%, 86%, 111% and 183% of the net ecosystem exchange of the control site under control, 50R, 100R and TI sites, respectively. (3) After three years' treatment, erosion induced decrease in fine fractions led to 31%, 43%, 85% of permanent loss of C sequestration potential in the surface 5cm soil for 50R, 100R and TI sites. Overall, our study demonstrates that lateral C flux associated with wind erosion is too large to be ignored. The loss of C-enriched fine particles not only reduces current ecosystem C content, but also results in irreversible loss of future soil C sequestration potential. The dynamic soil characteristics need be considered when projecting future ecosystem C balance in aeolian landscape. We also propose that to maintain the sustainability of grassland ecosystems, land managers should focus on implementing appropriate land use rather than rely on subsequent managements on degraded soils.

  8. Dental caries and its association with sociodemographics, erosion, and diet in schoolchildren from southeast Brazil.

    LENUS (Irish Health Repository)

    Auad, Sheyla Marcia

    2009-05-01

    The purposes of this study were to determine the prevalence of caries in a sample of Brazilian schoolchildren, test associotions between caries, sociodemographics, and erosion, and investigate potential dietary factors common to both conditions.

  9. Surface erosion of fusion reactor components due to radiation blistering and neutron sputtering

    International Nuclear Information System (INIS)

    Das, S.K.; Kaminsky, M.

    1975-01-01

    Radiation blistering and neutron sputtering can lead to the surface erosion of fusion reactor components exposed to plasma radiations. Recent studies of methods to reduce the surface erosion caused by these processes are discussed

  10. THE MOTRU MINING BASIN – GIS APPLICATION ON SHEET EROSION

    Directory of Open Access Journals (Sweden)

    Anghel TITU

    2008-05-01

    Full Text Available The Motru Mining Basin – GIS Application on Sheet Erosion. The activation of the sheet erosion has important negative effects upon the soil profile. The anticipation of this geomorphologic process is important for taking some measures for protecting the susceptible areas. Within our study, we will carry out a quantitative estimation of the soil losses in the Motru Mining Basin, caused by the activation of the sheet erosion mechanism. We will apply the classic methodology proposed by the ROMSEM model of the USLE type by using the GIS technology

  11. Erosion reasons and rate on accumulative Polish dune coast caused by the January 2012 storm surge

    Directory of Open Access Journals (Sweden)

    Tomasz A. Łabuz

    2014-03-01

    Full Text Available The Polish coast is a non-tidal area; its shores are affected mainly by autumn-winter storm surges. Those of 6 and 14 January 2012 are representative of the forces driving the erosion of normally accumulative sections of coastal dunes, monitored by the author since 1997. The sea level maximum during these two storm surges reached 1.2 to 1.5 m amsl along the Polish coast. Land forms up to 3 m amsl were inundated. Beaches and low parts of the coast up to this height were rebuilt by sea waves attacking the coast for almost 12 days. Quantitative analyses of the morphological dynamics of the coastal dunes are presented for 57 profiles located along the coast. Only those accumulative sections of the Polish coast are analysed where sand accumulation did occur and led to new foredune development. The mean rate of dune erosion was 2.5 m3 per square metre with an average toe retreat of 1.4 m. Erosion understood as dune retreat was greater when a beach was lower (correlation coefficient 0.8. Dune erosion did not occur on coasts with beaches higher than 3.2 m or on lower ones covered by embryo dunes.

  12. Beach erosion control study at Pass Christian. [using remote sensors and satellite observation

    Science.gov (United States)

    1978-01-01

    The methods of measuring the existence of erosion and the effects of sand stabilization control systems are described. The mechanics of sand movement, the nature of sand erosion, and the use of satellite data to measure these factors and their surrogates are discussed using the locational and control aspects of aeolian and litoral erosion zones along the sand beach of the Mississippi coast. The aeolian erosion is highlighted due to the redeposition of the sand which causes high cleanup costs, property damage, and safety and health hazards. The areas of differential erosion and the patterns of beach sand movement are illustrated and the use of remote sensing methods to identify the areas of erosion are evaluated.

  13. The influence of varnish and high fluoride on erosion and abrasion in a laboratory investigation.

    Science.gov (United States)

    Sar Sancakli, H; Austin, R S; Al-Saqabi, F; Moazzez, R; Bartlett, D

    2015-03-01

    The aim of this study was to investigate the potential of concentrated fluoride varnishes to reduce enamel loss from repeated cycles of citric acid erosion and toothbrush abrasion in vitro. Polished human enamel samples were exposed to fluoride varnishes: Bifluorid10® (NaF&CaF2- 45,200 ppmF), Duraphat® (NaF 22,600 ppmF), Fluor-Protector® (difluorsilane 1000 ppmF) and a control coating of copal ether varnish (0 ppmF) group and a deionized water group. For each group of 16 samples, nine cycles of erosion and nine cycles of erosion-abrasion [1 cycle=erosion (0.3% citric acid, pH 3.2, 5 min)+artificial saliva (1 h, pH 7.0)+abrasion (120 linear strokes in artificial saliva from Oral B medium soft brushes 300 g loading]. The change in the enamel surface was evaluated using optical profilometry. Duraphat® and Bifluorid10® applications had a median (IQR) step height of 4.21 um (1.59) and 5.01 um (1.02). This was statistically significantly less than Fluor-Protector® 6.83 um (1.25), copal ether 7.22 um (1.97) and water 7.39 um (1.96) (pDental Association.

  14. [Cervicofacial cellulitis of dental origin: etiology, epidemiological and therapeutic aspects].

    Science.gov (United States)

    Lawson Afouda, S; Avakoudjo, F; Alamou, S; Hounkpatin, S H R; Satowakou, M; Hounkpè, Y Y C; Adjibabi, W

    2012-01-01

    Cervicofacial cellulitises are dominated by dental affections. The aim of this study is to describe etio-epidemiological and therapeutic aspects of cervicofacial cellulitis of dental cause at the CNHU-HKM in Cotonou (Benin). It's a retrospective study from 1998 to 2007 included patients with inflammatory cervicofacial tumefaction of dental cause. A glycaemia, a HIV serology and a blood formula numeration are realized. Some patients practiced standard oral and dental radio. Patients were hospitalized and received mono, bi or triple antibiotic. Lancing with swab of pus for cytobacteriological and antibiogram examination was realized for some of patients. Dental cares were been systematic. 68 cases whose 53 dental cause where been collected 77.94%. Bracket concern patients between 0-20 and 20-40 years old (64.15%). Males were, more concerned. Dental traumatisms find again (18.88%), tooth decay (56.60%) and 24.53% patients practiced dental extraction. Anti inflammatory practiced by 67.92% patients associated to antibiotic in 41.51% cases. The three latest molar were concerned to 26 patients. Among those last 22 had attack of mandibular teeth. Treatment consisted in lancing drainage to 2/3 patients in 83.40% cases associated to tri antibiotic. Evolution has been favourable with recovery to 86.67%; 6 decreases to 13.33% cases. Cervicofacial cellulitises are dangerous, rapidly responsible of deceases by extension. A better oral and dental hygiene would improved prognosis.

  15. Oral, Maxillofacial and Dental Diseases in Captive Cheetahs (Acinonyx jubatus).

    Science.gov (United States)

    Steenkamp, G; Boy, S C; van Staden, P J; Bester, M N

    2018-01-01

    Descriptions of several oral, maxillofacial and dental conditions/diseases exist for a variety of captive large felids, but little is reported on the pathology of free roaming large felids. Apart from focal palatine erosions (FPEs) as initially described by Fitch and Fagan (1982) and some reference to absent incisor teeth, few data exist on diseases affecting the oral, maxillofacial and dental structures of cheetahs (Acinonyx jubatus), regardless of their captivity status. This study reports 18 different conditions affecting the teeth, bone and oral cavity soft tissue of cheetahs, based on initial assessment of 256 animals over 11 years (2002-2012) in South Africa and Namibia. This report excludes oral tumours or FPEs, but includes several acquired and developmental conditions never described before. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Effect of vegetation cover and transitions on regional wind erosion in drylands

    NARCIS (Netherlands)

    Youssef, I.F.

    2012-01-01

    Wind erosion is a critical environmental problem that threatens mainly the arid and semi-arid regions of our planet. Usually this problem is associated with desertification, poverty and other environmental and socioeconomic problems. Wind erosion causes the loss of fertile topsoil, and has a

  17. Remote sensing data applied to the evaluation of soil erosion caused by land-use. Ribeirao Anhumas Basin Area: A case study. [Brazil

    Science.gov (United States)

    Dejesusparada, N. (Principal Investigator); Dosanjosferreirapinto, S.; Kux, H. J. H.

    1980-01-01

    Formerly covered by a tropical forest, the study area was deforested in the early 40's for coffee plantation and cattle raising, which caused intense gully erosion problems. To develop a method to analyze the relationship between land use and soil erosion, visual interpretations of aerial photographs (scale 1:25.000), MSS-LANDSAT imagery (scale 1:250,000), as well as automatic interpretation of computer compatible tapes by IMAGE-100 system were carried out. From visual interpretation the following data were obtained: land use and cover tapes, slope classes, ravine frequency, and a texture sketch map. During field work, soil samples were collected for texture and X-ray analysis. The texture sketch map indicate that the areas with higher slope angles have a higher susceptibilty to the development of gullies. Also, the over carriage of pastureland, together with very friable lithologies (mainly sandstone) occuring in that area, seem to be the main factors influencing the catastrophic extension of ravines in the study site.

  18. Education About Dental Hygienists' Roles in Public Dental Prevention Programs: Dental and Dental Hygiene Students' and Faculty Members' and Dental Hygienists' Perspectives.

    Science.gov (United States)

    Pervez, Anushey; Kinney, Janet S; Gwozdek, Anne; Farrell, Christine M; Inglehart, Marita R

    2016-09-01

    In 2005, Public Act No. 161 (PA 161) was passed in Michigan, allowing dental hygienists to practice in approved public dental prevention programs to provide services for underserved populations while utilizing a collaborative agreement with a supervising dentist. The aims of this study were to assess how well dental and dental hygiene students and faculty members and practicing dental hygienists have been educated about PA 161, what attitudes and knowledge about the act they have, and how interested they are in additional education about it. University of Michigan dental and dental hygiene students and faculty members, students in other Michigan dental hygiene programs, and dental hygienists in the state were surveyed. Respondents (response rate) were 160 dental students (50%), 63 dental hygiene students (82%), 30 dental faculty members (26%), and 12 dental hygiene faculty members (52%) at the University of Michigan; 143 dental hygiene students in other programs (20%); and 95 members of the Michigan Dental Hygienists' Association (10%). The results showed that the dental students were less educated about PA 161 than the dental hygiene students, and the dental faculty members were less informed than the dental hygiene faculty members and dental hygienists. Responding dental hygiene faculty members and dental hygienists had more positive attitudes about PA 161 than did the students and dental faculty members. Most of the dental hygiene faculty members and dental hygienists knew a person providing services in a PA 161 program. Most dental hygiene students, faculty members, and dental hygienists wanted more education about PA 161. Overall, the better educated about the program the respondents were, the more positive their attitudes, and the more interested they were in learning more.

  19. Comparison of erosion and erosion control works in Macedonia, Serbia and Bulgaria

    Directory of Open Access Journals (Sweden)

    Ivan Blinkov

    2013-12-01

    Natural conditions in the Balkan countries contribute to the appearance of various erosion forms and the intensity of the erosion processes. Over the history of these countries, people who settled this region used the available natural resources to fill their needs (tree cutting, incorrect plugging, overgrazing, which contributed to soil erosion. Organized erosion control works in the Balkans started in the beginning of the 20th century (1905 in Bulgaria. The highest intensity of erosion control works were carried out during the period 1945 – 1990. Various erosion control works were launched. Bulgaria had a large anti-erosion afforestation, almost 1 million ha. Bulgaria's ecological river restoration approach has been in use for almost 50 years. Serbia contributed significant erosion and torrent control works on hilly agricultural areas. Specific screen barrages and afforestation on extremely dry areas are characteristic in Macedonia. A common characteristic for all countries is a high decrease in erosion control works in the last 20 years.

  20. Erosion-corrosion

    International Nuclear Information System (INIS)

    Aghili, B.

    1999-05-01

    A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment

  1. The Anatomical Nature of Dental Paresthesia: A Quick Review

    Science.gov (United States)

    Ahmad, Maha

    2018-01-01

    Dental paresthesia is loss of sensation caused by maxillary or mandibular anesthetic administration before dental treatment. This review examines inferior alveolar block paresthesia symptoms, side effect and complications. Understanding the anatomy of the pterygomandibular fossa will help in understanding the nature and causes of the dental paresthesia. In this review, we review the anatomy of the region surrounding inferior alveolar injections, anesthetic agents and also will look also into the histology and injury process of the inferior alveolar nerve. PMID:29541262

  2. Response of wind erosion dynamics to climate change and human activity in Inner Mongolia, China during 1990 to 2015.

    Science.gov (United States)

    Zhang, Haiyan; Fan, Jiangwen; Cao, Wei; Harris, Warwick; Li, Yuzhe; Chi, Wenfeng; Wang, Suizi

    2018-10-15

    Soil erosion caused by wind is a serious environmental problem that results in land degradation and threatens sustainable development. Accurately evaluating wind erosion dynamics is important for reducing the hazard of wind erosion. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. Based on meteorological, remote sensing and field observation data, we applied the Revised Wind Erosion Equation (RWEQ) to simulate wind erosion in Inner Mongolia, China from 1990 to 2015. We used the variable control method by input of the average climate conditions to calculate human-induced wind erosion. The difference between natural wind erosion and human-induced wind erosion was determined to assess the effect of climate change on wind erosion. The results showed that the wind erosion modulus had a remarkable decline with a slope of 52.23 t/km 2 /a from 1990 to 2015. During 26 years, the average wind erosion for Inner Mongolia amounted to 63.32 billion tons. Wind erosion showed an overall significant decline of 49.23% and the partial severer erosion hazard significantly increased by 7.11%. Of the significant regional decline, 40.72% was caused by climate changes, and 8.51% was attributed to ecological restoration programs. For the significant regional increases of wind erosion, 4.29% was attributed to climate changes and 2.82% to human activities, mainly overgrazing and land use/cover changes. During the study, the driving forces in Inner Mongolia of wind erosion dynamics differed spatially. Timely monitoring based on multi-source data and highlighting the importance of positive human activities by increasing vegetation coverage for deserts, reducing grazing pressure on grasslands, establishing forests as windbreaks and optimizing crop planting rotations of farmlands can all act to reduce and control wind erosion. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Tooth wear

    Directory of Open Access Journals (Sweden)

    Tušek Ivan

    2014-01-01

    Full Text Available Tooth wear is the loss of dental hard tissue that was not caused by decay and represents a common clinical problem of modern man. In the etiology of dental hard tissue lesions there are three dominant mechanisms that may act synergistically or separately:friction (friction, which is caused by abrasion of exogenous, or attrition of endogenous origin, chemical dissolution of dental hard tissues caused by erosion, occlusal stress created by compression and flexion and tension that leads to tooth abfraction and microfracture. Wear of tooth surfaces due to the presence of microscopic imperfections of tooth surfaces is clinically manifested as sanding veneers. Tribology, as an interdisciplinary study of the mechanisms of friction, wear and lubrication at the ultrastructural level, has defined a universal model according to which the etiopathogenesis of tooth wear is caused by the following factors: health and diseases of the digestive tract, oral hygiene, eating habits, poor oral habits, bruxism, temporomandibular disorders and iatrogenic factors. Attrition and dental erosion are much more common in children with special needs (Down syndrome. Erosion of teeth usually results from diseases of the digestive tract that lead to gastroesophageal reflux (GER of gastric juice (HCl. There are two basic approaches to the assessment of the degree of wear and dental erosion. Depending on the type of wear (erosion, attrition, abfraction, the amount of calcium that was realised during the erosive attack could be determined qualitatively and quantitatively, or changes in optical properties and hardness of enamel could be recorded, too. Abrasion of teeth (abrasio dentium is the loss of dental hard tissue caused by friction between the teeth and exogenous foreign substance. It is most commonly provoked by prosthetic dentures and bad habits, while its effect depends on the size of abrasive particles and their amount, abrasive particle hardness and hardness of tooth

  4. Assessing the causes for the dentistry selection as a job by Iranian dental students: A Questionnaire Survey

    Science.gov (United States)

    Hamissi, J; Bairami, P; Hamissi, Z

    2015-01-01

    Objective: The purpose of the current research is to discover the causes for the dentistry selection as a profession by senior dental scholars in Iran. Materials & Methods: Surveys are distributed between the first-year to the sixth-year senior dental scholars at the Scholl of Dentistry in Medical Sciences Qazvin University in Iran. The survey presented in a lecture hall at the terminal of the secondary term in the 2011-2012 academic years. The survey included 30 parts, and the pupils asked to measure the significance of any part for choosing dentistry as a profession, on a 10-points scale. In addition, T-test and ANOVA utilized for the data analysis. Results: The answering ratio in the research is 55% (out of 100%) of the pupils delivered. Ninety-six students (93.2%) selected it as an initial selection. Dentistry as a job which is “insurer of financial independence” was gained a most rate via 82.5% of the pupils raised and a comparable amount of the students (75.7%), assigned a highest rate to the parameter “I love to enhance many money”. Dentistry as a “science-based job” was also given a score by 80.6% of the pupils. Conclusion: There are no variations in the motivation between men and women students. It obtained that “insurer of financial independence” and “I love to enhance many money” are critical action parameters in the dental pupils population. PMID:28316683

  5. Er,Cr:YSGG Laser Energy Delivery: Pulse and Power Effects on Enamel Surface and Erosive Resistance.

    Science.gov (United States)

    de Oliveira, Renan Mota; de Souza, Vinicius Matsuzaki; Esteves, Camila Machado; de Oliveira Lima-Arsati, Ynara Bosco; Cassoni, Alessandra; Rodrigues, José Augusto; Brugnera Junior, Aldo

    2017-11-01

    High power lasers have been suggested as a useful tool for dental caries and erosion prevention due to the increase of enamel acid resistance. to evaluate the effect of Er,Cr:YSGG (erbium,chromium:yttrium, scandium, gallium, garnet) laser irradiation pulse frequency and power on enamel surface and acid erosion resistance. By combining pulse frequency (5-75 Hz) and power settings (0.10-1.00 W), 20 irradiated groups and one nonirradiated control group were tested. A total of 63 bovine enamel blocks (n = 3/group) were prepared for surface hardness and roughness evaluation, performed in three phases: baseline, after irradiation, and after erosive challenge. Enamel blocks were irradiated with Er,Cr:YSGG laser with MZ8 tip (iPlus; Waterlase, Biolase, CA) for 30 sec according to experimental group and submitted. Erosive challenge consisted of four cycles alternating immersion in 0.01 M HCl (5 mL/mm 2 ; 2 min; at 37°C) and immersion in artificial saliva for 3 h. Analysis of variance (three-way ANOVA), Tukey's test, and Pearson correlation were performed for the statistical analysis (p hardness. After erosive challenge, 5 and 75 W groups showed increase in surface hardness; 0.25, 0.5, 0.75, and 1 W groups showed minor alterations in surface roughness. the irradiation of Er,Cr:YSGG laser with different parameters of power and pulse frequency settings may alter enamel surface and erosive resistance differently. Pulse frequency of 30 Hz and power of 0.50 W was considered the best parameter to prevent enamel acid erosion.

  6. 4-phenylbutyrate Mitigates Fluoride-Induced Cytotoxicity in ALC Cells

    OpenAIRE

    Suzuki, Maiko; Everett, Eric T.; Whitford, Gary M.; Bartlett, John D.

    2017-01-01

    Chronic fluoride over-exposure during pre-eruptive enamel development can cause dental fluorosis. Severe dental fluorosis is characterized by porous, soft enamel that is vulnerable to erosion and decay. The prevalence of dental fluorosis among the population in the USA, India and China is increasing. Other than avoiding excessive intake, treatments to prevent dental fluorosis remain unknown. We previously reported that high-dose fluoride induces endoplasmic reticulum (ER) stress and oxidative...

  7. Erosion-corrosion interactions and their affect on marine and offshore components

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Robert JK [Surface Engineering and Tribology Group, School of Engineering Sciences, University of Southampton, SO17 1BJ (United Kingdom)

    2004-07-01

    The operation of modern fluid handling systems demands for low costs, reliability, longevity and no loss of fluid containment. All these can be achieved by minimising the material damage caused by the combined attack of solid particle or cavitation impingement and corrosion. This paper will cover the rationale behind the selection of erosion resistance surfaces for fluid handling equipment and highlight the complexities encountered when these surfaces are exposed to environments which contain sand particles or cavitation in a corrosive medium. The erosion and erosion-corrosion performance of a variety of coatings and bulk surfaces will be discussed using volume loss rate versus sand impact energy maps. Recent research into the erosion-corrosion of polymer coatings, PEO and HVOF aluminium and nickel aluminium bronze coatings will be reviewed. Electrochemical techniques designed to monitor the erosion-corrosion mechanisms and coating integrity will be presented and used to quantify the synergistic terms present when both erosion and corrosion act concurrently. (author)

  8. The similarity of river evolution at the initial stage of channel erosion

    Science.gov (United States)

    Lin, Jiun-Chuan

    2014-05-01

    The study deals with a comparison study of two types of rocks at the initial stage of channel erosion in Taiwan. It is interesting that channel erosion at different types of rocks shows some similarity. There are two types of rocks: sandstone at Ta-an River, central Taiwan where river channel erosion from the nick point because of earthquake uplifting and mud rock at Tainan, southern Taiwan where rill erosion on a flat surface after artificial engineering. These two situations are both at the beginning stage of channel erosion, there are some similar landform appeared on channels. However the rate of erosion and magnitude of erosion are different. According to the using of photogrammetry method to reconstruct archive imageries and field surveying by total station and 3D scanner at different stages. The incision rate is high both at the Ta-an River and the bank erosion and it is even more obvious at mud rock area because of erodibility of mud rock. The results show that bank erosion and incision both are obvious processes. Bank erosion made channel into meander. The bank erosion cause slope in a asymmetric channel profile. The incision process will start at the site where land is relatively uplifted. This paper demonstrates such similarity and landform characters.

  9. The Frequencies of Gastroesophageal and Extragastroesophageal Symptoms in Patients with Mild Erosive Esophagitis, Severe Erosive Esophagitis, and Barrett’s Esophagus in Taiwan

    Directory of Open Access Journals (Sweden)

    Sung-Shuo Kao

    2013-01-01

    Full Text Available Background. Gastroesophageal reflux disease (GERD may present with gastroesophageal and extraesophageal symptoms. Currently, the frequencies of gastroesophageal and extragastroesophageal symptoms in Asian patients with different categories of GERD remain unclear. Aim. To investigate the frequencies of gastroesophageal and extragastroesophageal symptoms in patients with mild erosive esophagitis, severe erosive esophagitis, and Barrett’s esophagus of GERD. Methods. The symptoms of symptomatic subjects with (1 Los Angeles grade A/B erosive esophagitis, (2 Los Angeles grade C/D erosive esophagitis, and (3 Barrett’s esophagus proven by endoscopy were prospectively assessed by a standard questionnaire for gastroesophageal and extragastroesophageal symptoms. The frequencies of the symptoms were compared by Chi-square test. Result. Six hundred and twenty-five patients (LA grade A/B: 534 patients; LA grade C/D: 37 patients; Barrett’s esophagus: 54 patients were assessed for gastroesophageal and extragastroesophageal symptoms. Patients with Los Angeles grade A/B erosive esophagitis had higher frequencies of symptoms including epigastric pain, epigastric fullness, dysphagia, and throat cleaning than patients with Los Angeles grade C/D erosive esophagitis. Patients with Los Angeles grade A/B erosive esophagitis also had higher frequencies of symptoms including acid regurgitation, epigastric acidity, regurgitation of food, nausea, vomiting, epigastric fullness, dysphagia, foreign body sensation of throat, throat cleaning, and cough than patients with Barrett’s esophagus. Conclusion. The frequencies of some esophageal and extraesophageal symptoms in patients with Los Angeles grade A/B erosive esophagitis were higher than those in patients with Los Angeles grade C/D erosive esophagitis and Barrett’s esophagus. The causes of different symptom profiles in different categories of GERD patients merit further investigations.

  10. Remontant erosion in desert soils of Tamaulipas, México.

    Science.gov (United States)

    Rivera-Ortiz, P.; Andrade-Limas, E.; De la Garza-Requena, F.; Castro-Meza, B.

    2012-04-01

    REMONTANT EROSION IN DESERT SOILS OF TAMAULIPAS MÉXICO Rivera-Ortiz, P.1; Andrade-Limas, E.1; De la Garza-Requena, F.1 and Castro-Meza, B.1 1Facultad de Ingeniería y Ciencias, Universidad Autónoma de Tamaulipas, México The degradation of soil reduces the capacity of soils to produce food and sustain life. Erosion is one of the main types of soil degradation. Hydric erosion of remontant type can occur in soils located close to the channel of a river through the expansion of a gully that begins as a fluvial incision over the ravine of one side of the river. The incision takes place at the point of greatest flow of runoff from areas adjacent to empty into the river. The depth of the incision causes the growth of the gully by collapse to move their heads back, upstream. The soil loss by remontant erosion on land use in agriculture and livestock was estimated in order to understand the evolution of gullies formed by this type of erosion. Through measurements on satellite images and GPS (Global Positioning System) two gullies, developed on alluvial soils which drain into the river Chihue, were studied. The investigation was conducted during 2003 to 2010 period in the municipality of Jaumave, Tamaulipas, in northeastern Mexico. Soil loss in gullies developed by remontant erosion was large and it was caused by soil collapse and drag of soil on the headers. The estimated loss of soil by remontant erosion was 3500 t in the deeper gully during 2010 and nearly 1200 t per year in the period 2003-2009. New sections of gully of about 20 m length, with more than 3 m deep and up to 13 m wide, were formed each year. This degradation has significantly reduced the productive surface of soil that for many years has been used to the cultivation of maize (Zea mays) and beans (Phaseolus vulgaris) as well as pasture production.

  11. Gastro-oesophageal reflux disease and dental erosions in adults: influence of acidified food intake and impact on quality of life.

    Science.gov (United States)

    Milani, Daiane C; Venturini, Ana Paula C; Callegari-Jacques, Sidia M; Fornari, Fernando

    2016-07-01

    Gastro-oesophageal reflux disease (GORD) and dental erosions (DE) have an established association. We assessed whether GORD is associated with DE controlling for acidified food intake and their relationships with quality of life (QOL). In this cross-sectional study, 419 adult patients who sought dentistry consultation were considered eligible. Patients responded to questionnaires for GORD symptoms, acidified food ingestion and World Health Organization quality of life (WHOQOL Bref), followed by an oral examination, in which DE were characterized according to the Smith & Knight criteria. A total of 417 patients were included (43.8±13.7 years; 68.8% women). There were 143 patients with GORD (34.3%) and 274 controls without GORD. The prevalence of DE was higher in GORD patients compared with the controls (25.9 vs. 17.2%; P=0.041). GORD was associated with DE after adjusting for acidified food intake (P=0.035), with a prevalence ratio of 1.52 (0.95 confidence interval 1.03-2.22). The WHOQOL Bref score was significantly lower in the presence of GORD [median 17.2 (GORD-DE-) vs. 15.4 (GORD+DE+); P<0.01], irrespective of DE. In adults examined in a referential dentistry centre in South America, DE were prevalent and significantly associated with GORD. This association was independent of the intake of acidified food in our study. Impairment in QOL was observed in GORD patients irrespective of the presence of DE.

  12. Imaging of the jaw cysts with a dental CT software program : distinction of odontogenic keratocysts from other cysts

    International Nuclear Information System (INIS)

    Lee, Jung Man; Shin, Sang Hoon; Lee, Won Hoon; Oh, Kyu Hyen; Jung, Hak Young; Lee, Young Hwan; Sung, Nak Kwan; Jung, Duck Soo; Kim, Ok Dong

    1997-01-01

    To evaluate the usefulness of a dental CT software program in the assessment of jaw cysts and in the differentiation of odontogenic keratocysts and other cysts. Seventeen patients with proven jaw cysts(8 maxillae and 9 mandibles) were evaluated with a dental CT sofware program for location, locularity, the presence or absence of marginal scallping, and height to length ratio. For the delineation of involvement or displace-ment of neurovascular bundles, cortical erosion, perforation or expansion, and tooth root resorption by the jaw cysts, images from this program were compared to conventional images. Seventeen lesions icomprised 15 odontogenic cysts (five odontogenic keratocysts, five radicular, three residual and two dentigerous cysts) and two non-odontogenic cysts (one nasopalatine duct cyst and one postoperative maxillary cyst). Images of jaw cysts obtained with the dental CT software program delineated much more clearly than conventional images the status of neurovascular bundle and cortical bone, but there was no clear difference between the two modalities in delineating tooth root erosion. Dental CT findings of five mandibular odontogenic keratocysts were scalloped margin in all, mandibular ramus involvement in four, height to length ratio below 60% in four ,and multilocularity in two. The findings of the other 12 cysts (eight maxillae and four mandibles) were unilocularity in all, smooth inner margin in ten, height to length ratio below 60% in only two, and ramus involvement in none. A dental CT software program is an improved imaging modality for assessing jaw cysts;and findings which tend to indicate odontogenic keratocysts are marginal scalloping, mandibular ramus involvement, prominent spread along the marrow space and multilocularity

  13. Modelling erosion on a daily basis, an adaptation of the MMF approach

    NARCIS (Netherlands)

    Shrestha, Dhruba Pikha; Jetten, Victor G.

    2018-01-01

    Effect of soil erosion causing negative impact on ecosystem services and food security is well known. On the other hand there can be yearly variation of total precipitation received in an area, with the presence of extreme rains. To assess annual erosion rates various empirical models have been

  14. Simulating soil erosion risk for Pan-European land use and climate scenarios

    NARCIS (Netherlands)

    Mantel, S.; Kirby, M.; Daroussin, J.; Jones, R.J.A.

    2003-01-01

    Soil is a vital resource with multiple functions and with high regional and internal variability. Accelerated soil erosion is a cause for decline in soil quality and is increasingly being recognized as a serious environmental problem. Soil erosion is a function of factors such as: land use and

  15. Utilization of radiometric method in evaluation of wear on human dental enamel in vitro by dental porcelain glazed and polished

    International Nuclear Information System (INIS)

    Adachi, Lena Katekawa; Campos, Tomie Nakakuki de; Adachi, Eduardo Makoto

    2005-01-01

    The dental porcelain is a material commonly used in prosthesis. Disadvantages of dental porcelain use include possibility to cause tooth or dental materials wear. Before its use in the mouth, surfaces are treated with polishing and/or glazing. This research used the radiometric method to verify the influence of these surface treatments on the porcelains of commercial brands: Ceramco II, Noritake and Finesse. This method was originally developed for dentifrice abrasiveness evaluation. Five specimens of dental enamel and 10 specimens of each porcelain (5 glazed, 5 polished) were used. The dental enamel was flattened and irradiated with neutrons from the IEA-R1 (IPEN/CNEN) nuclear reactor. Then it was weared by each porcelain in sliding motion, with water. After 2,500 cycles for each porcelain specimen, the released enamel residue was measured. The enamel wear was evaluated by measuring beta activity of 32 P transferred to water from the irradiated tooth. Results varied from 2.57 to 5.81 μg of enamel /mm 2 weared surface. There was no statistical difference (α=0.05) between dental enamel wear caused by the same porcelains glazed or polished. The results suggest that adequate surface finishing depend on the type of dental porcelain. (author)

  16. Mercury flow experiments. 4th report: Measurements of erosion rate caused by mercury flow

    International Nuclear Information System (INIS)

    Kinoshita, Hidetaka; Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro

    2002-06-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a construction plan of the Material-Life Science Facility, which is consisted of a Muon Science Facility and a Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutron generated by the spallation reaction of a 1 MW pulsed proton beam and mercury target. Design of the spallation mercury target system aims to obtain high neutron performance with high reliability and safety. Since the target system is using mercury as the target material and contains large amount of radioactive spallation products, it is necessary to estimate reliability for strength of instruments in a mercury flow system during lifetime of the facility. Piping and components in the mercury flow system would be damaged by erosion with mercury flow, since these components will be weak by thickness decreasing. This report presents experimental results of wall thickness change by erosion using a mercury experimental loop. In the experiments, an erosion test section and coupons were installed in the mercury experimental loop, and their wall thickness was measured with an ultra sonic thickness gage after every 1000 hours. As a result, under 0.7 m/s of mercury velocity condition which is slightly higher than the practical velocity in mercury pipelines, the erosion is about 3 μm in 1000 hours. The wall thickness decrease during facility lifetime of 30 years is estimated to be less than 0.5 mm. According to the experimental result, it is confirmed that the effect of erosion on component strength is extremely small. Moreover, a measurement of residual mercury on the piping surface was carried out. As a result, 19 g/m 2 was obtained as the residual mercury for the piping surface. According to this result, estimated amount of residual mercury for

  17. Mitigating Hillslope Erosion After Post-fire Salvage Logging Operations

    Science.gov (United States)

    Robichaud, P. R.; Bone, E. D.; Brown, R. E.

    2017-12-01

    In the past decades, wildfires around the world have continued to increase in size, severity, and cost. Major concerns after wildfires are the increased runoff and erosion due to loss of the protective forest floor layer, loss of water storage, and creation of water repellent soil conditions. Salvage logging is often a post-fire forest management action to recoup the economic loss of the burned timber, yet concerns arise on the impacts of this activity on water quality. Recently, several studies have been conducted to determine the effect of salvage logging on hillslope erosion. Logging skid trails have been cited as being the cause of high erosion during and after salvage operations. We investigated the impacts of adding operational logging slash to skid trails to reduce hillslope erosion after salvage operations on the 2015 North Star Fire, Washington. We implemented well-designed rapid response approach to compare slash treatment effectiveness by monitoring sediment yield and runoff response from hillslopes with a concentrated flow (rill) experiment. Various runoff amounts are incrementally added to 4 m hillslope plots with and without slash treatments. Our initial results suggest that adding logging slash increased ground cover significantly which contributed to an order of magnitude decrease in hillslope erosion. Integrating erosion mitigation strategies into salvage logging operations should be commonplace when hillslope erosion is a concern.

  18. Diabetes induces metabolic alterations in dental pulp.

    Science.gov (United States)

    Leite, Mariana Ferreira; Ganzerla, Emily; Marques, Márcia Martins; Nicolau, José

    2008-10-01

    Diabetes can interfere in tissue nutrition and can impair dental pulp metabolism. This disease causes oxidative stress in cells and tissues. However, little is known about the antioxidant system in the dental pulp of diabetics. Thus, it would be of importance to study this system in this tissue in order to verify possible alterations indicative of oxidative stress. The aim of this study was to evaluate some parameters of antioxidant system of the dental pulp of healthy (n = 8) and diabetic rats (n = 8). Diabetes was induced by streptozotocin in rats. Six weeks after diabetes induction, a pool of the dental pulp of the 4 incisors of each rat (healthy and diabetic) was used for the determination of total protein and sialic acid concentrations and catalase and peroxidase activities. Data were compared by a Student t test (p pulps from both groups presented similar total protein concentrations and peroxidase activity. Dental pulps of diabetic rats exhibited significantly lower free, conjugated, and total sialic acid concentrations than those of control tissues. Catalase activity in diabetic dental pulps was significantly enhanced in comparison with that of control pulps. The result of the present study is indicative of oxidative stress in the dental pulp caused by diabetes. The increase of catalase activity and the reduction of sialic acid could be resultant of reactive oxygen species production.

  19. Damage diagnostic of localized impact erosion by measuring acoustic vibration

    International Nuclear Information System (INIS)

    Futakawa, Masatoshi; Kogawa, Hiroyuki; Ikeda, Yujiro

    2004-01-01

    High power spallation targets for neutron sources are being developed in the world. Mercury target will be installed at the material and life science facility in J-PARC, which will promote innovative science. The mercury target is subject to the pressure wave caused by the proton bombarding mercury. The pressure wave propagation induces the cavitation in mercury that imposes localized impact erosion damage on the target vessel. The impact erosion is a critical issue to decide the lifetime of the target. The electric Magnetic IMpact Testing Machine, MIMTM, was developed to produce the localized impact erosion damage and evaluate the damage formation. Acoustic vibration measurement was carried out to investigate the correlation between the erosion damage and the damage potential derived from acoustic vibration. It was confirmed that the damage potential related with acoustic vibration is useful to predict the damage due to the localized impact erosion and to diagnose the structural integrity. (author)

  20. Stony meteoroid space erosion and drag: Effect on cosmic ray exposure ages

    Science.gov (United States)

    Rubincam, David Parry

    2017-09-01

    Collisions with dust particles in retrograde orbits cause space erosion on stony meteoroids in addition to the particle drag which causes drift toward resonances. The spacing between resonances determines the maximum drift time and sets upper limits on the neon-21 cosmic ray exposure (CRE) ages for meteoroids less than ∼1 m in radius, while space erosion controls the limit for radii greater than ∼1 m; the limits accord well with the measured CRE ages of stony meteorites.

  1. Trends of the gully erosion development in the territory of the Republic of Tatarstan

    Science.gov (United States)

    Medvedeva, R. A.

    2018-01-01

    Gully erosion is one of the most active geomorphic processes and one of the major cause of land degradation worldwide. The aim of the study was identifying the dynamics of gully erosion development in the Republic of Tatarstan. The interpretation of satellite images were used for evaluation of the modern dynamics of gullies. Two key indicators of gully erosion (length density and gully head density) were determined. Maps of modern gully erosion for a part of the Republic of Tatarstan were constructed.

  2. Dental Acrylics - Potential Agent for a Myriad of Diseases

    Directory of Open Access Journals (Sweden)

    Shivangi Gajwani

    2007-01-01

    Full Text Available An allergic reaction also known as a hypersensitivity reaction is caused by the immune system in response to a foreign substance (or allergen. Allergenic chemicals can be found in many products used in the dental operatory. With repeated exposure, these chemicals can cause allergic reactions in dental professionals, resulting in local as well as systemic manifestations. According to various studies done, it became evident that the prevalence of acrylic allergy most commonly in the form of allergic contact dermatitis is affecting the dental personnel to a much greater degree than is believed. Awareness of this disease complex in the form of any new symptoms and potential exposure is paramount for dental personals.

  3. Ergonomic risk: social representations of dental students

    Directory of Open Access Journals (Sweden)

    Luana Kelle Batista Moura

    2014-01-01

    Full Text Available Objective: To learn the social representations of ergonomic risk prepared ​​by dental students. Methodology: This exploratory study, subsidized the Theory of Social Representations, with 64 dental students of an educational institution, by means of interviews. The data were processed in Alceste4.8 and lexical analysis done by the descending hierarchical classification. Results: In two categories: knowledge about exposure to ergonomic risk end attitude of students on preventing and treating injuries caused by repetitive motion. For students, the ergonomic risk is related to the attitude in the dental office. Conclusion: Prevention of ergonomic risk for dental students has not been incorporated as a set of necessary measures for their health and the patients, to prevent ergonomic hazards that can result in harm to the patient caused by work-related musculoskeletal disorder, which is reflected in a lower quality practice.

  4. Dental Calculus Arrest of Dental Caries.

    Science.gov (United States)

    Keyes, Paul H; Rams, Thomas E

    An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. These observations further document the potential protective effects of dental calculus mineralization against dental caries.

  5. Dental Calculus Arrest of Dental Caries

    Science.gov (United States)

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  6. Craniofacial and dental development in Costello syndrome.

    Science.gov (United States)

    Goodwin, Alice F; Oberoi, Snehlata; Landan, Maya; Charles, Cyril; Massie, Jessica C; Fairley, Cecilia; Rauen, Katherine A; Klein, Ophir D

    2014-06-01

    Costello syndrome (CS) is a RASopathy characterized by a wide range of cardiac, musculoskeletal, dermatological, and developmental abnormalities. The RASopathies are defined as a group of syndromes caused by activated Ras/mitogen-activated protein kinase (MAPK) signaling. Specifically, CS is caused by activating mutations in HRAS. Although receptor tyrosine kinase (RTK) signaling, which is upstream of Ras/MAPK, is known to play a critical role in craniofacial and dental development, the craniofacial and dental features of CS have not been systematically defined in a large group of individuals. In order to address this gap in our understanding and fully characterize the CS phenotype, we evaluated the craniofacial and dental phenotype in a large cohort (n = 41) of CS individuals. We confirmed that the craniofacial features common in CS include macrocephaly, bitemporal narrowing, convex facial profile, full cheeks, and large mouth. Additionally, CS patients have a characteristic dental phenotype that includes malocclusion with anterior open bite and posterior crossbite, enamel hypo-mineralization, delayed tooth development and eruption, gingival hyperplasia, thickening of the alveolar ridge, and high palate. Comparison of the craniofacial and dental phenotype in CS with other RASopathies, such as cardio-facio-cutaneous syndrome (CFC), provides insight into the complexities of Ras/MAPK signaling in human craniofacial and dental development. © 2014 Wiley Periodicals, Inc.

  7. The Impact of Farming and Land Ownership on Soil Erosion

    Directory of Open Access Journals (Sweden)

    Olga Čermáková

    2014-01-01

    Full Text Available The aim of this paper was to compare two methods of farming, especially their effect on water soil erosion. The examined methods were (1 large-scale farming, where more than 50% of the land was leased, and (2 small-scale farming, where the land was almost exclusively privately owned. The research area was 8 cadastres in the district of Hodonín, South Moravia, Czech Republic. In these cadastres 48 land blocks representing both large-scale and small-scale farming (i.e. owners and tenants were chosen. The long-term average annual soil loss caused by water erosion (G was calculated using the erosion model USLE 2D and ArcGIS 10.1. The nonparametric Mann-Whitney test was used for the statistical evaluation of the data. The difference between the soil loss (G on land blocks farmed by small producers (owners and large producers (tenants was significant (p < 0.05. Differences between the values of the cropping-management factor (C were not statistically significant (p = 0.054. Based on the analysis of other variables in the USLE equation it can be stated that a continuous slope length, conditioned by the size of land blocks, played an important role in the amount of soil loss caused by water erosion. Above all, to protect the soil from erosion and maintain soil quality it is necessary to reduce the size of land blocks farmed by tenants and improve the crop rotation systems.

  8. Illuminating wildfire erosion and deposition patterns with repeat terrestrial lidar

    Science.gov (United States)

    Rengers, Francis K.; Tucker, G.E.; Moody, J.A.; Ebel, Brian

    2016-01-01

    with the lowest roughness. By contrast, in convergent areas we found erosion caused by overland flow. Soil erosion was locally interrupted by immobile objects such as boulders, bedrock, or tree trunks, resulting in a patchy erosion network with increasing roughness over time.

  9. Salivary gland doses from dental radiographic exposures

    International Nuclear Information System (INIS)

    Hoshi, Masaharu; Kato, Kazuo; Wada, Takuro; Antoku, Shigetoshi; Russell, W.J.

    1989-01-01

    Salivary gland doses incurred during dental radiography were measured by phantom dosimetry, and these dose data and data obtained during a two-week survey of Hiroshima and Nagasaki dental hospitals and clinics were used to estimate the respective doses to members of the populations of the two cities. The results obtained were used to supplement previously determined doses to the thyroid gland, lens, and pituitary gland from dental radiography. No significant differences in doses were observed by age, sex or city. Doses to the salivary glands during dental radiography are probably not sufficiently large to cause bias in assessments of atomic bomb survivors for late radiation effects. However, the steadily increasing use of dental radiography underscores the need for continued monitoring of dental radiography doses in the interests of these assessments. (author)

  10. Current status of mechanical erosion studies of bentonite buffer

    International Nuclear Information System (INIS)

    Sane, P.; Olin, M.; Koskinen, K.

    2013-08-01

    The performance of the bentonite buffer in KBS-3-type nuclear waste repository concept relies to a great extent on the buffer surrounding the canister having sufficient dry density. Loss of buffer material caused by erosion remains as the most significant process reducing the density of the buffer. The mechanical erosion, or pre-saturation erosion, is the process where flowing groundwater transports buffer material away from the deposition hole towards the deposition tunnel. This process reduces the overall buffer density and potentially creates localized regions of low density. In the worst case the process is assumed to last as long as the free volume between the pellets in the pellets filled regions is filled with groundwater. With fixed environmental and material parameters a set of experiments was performed, testing the erosive properties of different buffer and backfill materials (MX-80 and Friedland Clay) in different groundwater conditions. The method used was a pinhole erosion test using two sizescales; 100 mm and 400 mm of cell length. The purpose of the pinhole tests was to test the scenario where piping channel is formed in the buffer and water flows through a single channel. The erosion data was produced with two methods, firstly the time-related erosion rates measured in-situ during the measurement and secondly the overall mass loss in the sample cell measured after dismantling of the test. It was observed that erosion in piping channels decreases rapidly (∼24 h) and irreversibly to a level that is an order of magnitude lower than the peak values. (orig.)

  11. Riparian erosion vulnerability model based on environmental features.

    Science.gov (United States)

    Botero-Acosta, Alejandra; Chu, Maria L; Guzman, Jorge A; Starks, Patrick J; Moriasi, Daniel N

    2017-12-01

    Riparian erosion is one of the major causes of sediment and contaminant load to streams, degradation of riparian wildlife habitats, and land loss hazards. Land and soil management practices are implemented as conservation and restoration measures to mitigate the environmental problems brought about by riparian erosion. This, however, requires the identification of vulnerable areas to soil erosion. Because of the complex interactions between the different mechanisms that govern soil erosion and the inherent uncertainties involved in quantifying these processes, assessing erosion vulnerability at the watershed scale is challenging. The main objective of this study was to develop a methodology to identify areas along the riparian zone that are susceptible to erosion. The methodology was developed by integrating the physically-based watershed model MIKE-SHE, to simulate water movement, and a habitat suitability model, MaxEnt, to quantify the probability of presences of elevation changes (i.e., erosion) across the watershed. The presences of elevation changes were estimated based on two LiDAR-based elevation datasets taken in 2009 and 2012. The changes in elevation were grouped into four categories: low (0.5 - 0.7 m), medium (0.7 - 1.0 m), high (1.0 - 1.7 m) and very high (1.7 - 5.9 m), considering each category as a studied "species". The categories' locations were then used as "species location" map in MaxEnt. The environmental features used as constraints to the presence of erosion were land cover, soil, stream power index, overland flow, lateral inflow, and discharge. The modeling framework was evaluated in the Fort Cobb Reservoir Experimental watershed in southcentral Oklahoma. Results showed that the most vulnerable areas for erosion were located at the upper riparian zones of the Cobb and Lake sub-watersheds. The main waterways of these sub-watersheds were also found to be prone to streambank erosion. Approximatively 80% of the riparian zone (streambank

  12. Investigation of contact allergy to dental materials by patch testing

    Directory of Open Access Journals (Sweden)

    Reena Rai

    2014-01-01

    Full Text Available Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG. Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials.

  13. Rainfall Erosivity in Europe

    DEFF Research Database (Denmark)

    Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale

    2015-01-01

    Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the Rfactor in the USLE model and its revised version, RUSLE. At national...... and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based...

  14. Effect of Bend Radius on Magnitude and Location of Erosion in S-Bend

    Directory of Open Access Journals (Sweden)

    Quamrul H. Mazumder

    2015-01-01

    Full Text Available Solid particle erosion is a mechanical process that removes material by the impact of solid particles entrained in the flow. Erosion is a leading cause of failure of oil and gas pipelines and fittings in fluid handling industries. Different approaches have been used to control or minimize damage caused by erosion in particulated gas-solid or liquid-solid flows. S-bend geometry is widely used in different fluid handling equipment that may be susceptible to erosion damage. The results of a computational fluid dynamic (CFD simulation of diluted gas-solid and liquid-solid flows in an S-bend are presented in this paper. In addition to particle impact velocity, the bend radius may have significant influence on the magnitude and the location of erosion. CFD analysis was performed at three different air velocities (15.24 m/s–45.72 m/s and three different water velocities (0.1 m/s–10 m/s with entrained solid particles. The particle sizes used in the analysis range between 50 and 300 microns. Maximum erosion was observed in water with 10 m/s, 250-micron particle size, and a ratio of 3.5. The location of maximum erosion was observed in water with 10 m/s, 300-micron particle size, and a ratio of 3.5. Comparison of CFD results with available literature data showed reasonable and good agreement.

  15. Estimating surface soil erosion losses and mapping erosion risk for Yusufeli micro-catchment (Artvin

    Directory of Open Access Journals (Sweden)

    Mustafa Tüfekçioğlu

    2016-10-01

    Full Text Available Sheet erosion, one of the most important types of water erosion, takes place on the top soil as tiny soil layer movement that affects lake and stream ecosystem. This type of erosion is very important because the productive soil layer on the top soil can be lost in a very short period of time. The goal of this study was to quantify the amount of surface (sheet and rill soil erosion, and to identify areas under high erosion risk within the study area at Yusufeli province in Artvin by using RUSLE erosion methodology. As a result of the study it was found that the average annual potential soil loss by surface erosion was 3.6 ton ha-1yr-1. Additionally, the maps produced and conclusions reached by the study revealed that the areas of high erosion risk were identified spatially and measures to control erosion on some of these high risk areas can be possible with appropriate erosion control techniques.

  16. Evaluation of MRI artifacts caused by metallic dental implants and classification of the dental materials in use

    Czech Academy of Sciences Publication Activity Database

    Starčuk jr., Zenon; Bartušek, Karel; Hubálková, H.; Bachorec, T.; Starčuková, Jana; Krupa, P.

    2006-01-01

    Roč. 6, č. 2 (2006), s. 24-27 ISSN 1335-8871 R&D Projects: GA MZd NR8110 Institutional research plan: CEZ:AV0Z20650511 Keywords : magnetic resonance imaging * artifacts * metallic implants * dental alloys * magnetic susceptibility Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  17. Headcut erosive regimes influenced by groundwater on disturbed agricultural soils.

    Science.gov (United States)

    Rockwell, D L

    2011-02-01

    A series of simulated rainfall experiments, testing several soils and slope gradients in a 10 m x 0.8m laboratory flume, displayed close correlations between initial development of a water table at a 10 cm depth and highly erosive headcut formation. On some soils and gradients, highly erosive headcuts formed consistently and predictably within minutes or seconds of initial water table rise. However, headcuts alone were not good indicators of increased erosion. In most experiments some headcuts formed early, often when surface hydraulic parameter values reached established rill initiation thresholds, but resulted in little or no erosion increase. Later, at initial water table rise, other headcuts formed coincident with major erosion increase, often with surface hydraulic values then less than rill initiation thresholds. On the four soils tested, highly erosive headcuts never formed without groundwater development, except on steep 9 ° slopes. Common visual indicators such as headcut morphology and headcut advance rates were not effective means of determining either erosion or the existence of groundwater. Only local monitoring of subsurface moisture conditions with micro-standpipes and TDR aided in determining headcut processes and erosive regimes. Groundwater-influenced headcut formation was likely caused by increased soil pore-water pressures and decreased soil shear strengths in surface rainflow, not by sapping or seepage from the soil matrix. Highly erosive headcuts can thus form under common agricultural conditions where reductions in permeability, such as plow pans, exist near the surface--without the need for saturated soils. Headcut erosive regimes were also significantly influenced by soil type and slope gradient, with the greatest effects of groundwater on moderate slopes and fairly permeable soils. Copyright © 2010. Published by Elsevier Ltd.

  18. The comparison of various approach to evaluation erosion risks and design control erosion measures

    Science.gov (United States)

    Kapicka, Jiri

    2015-04-01

    In the present is in the Czech Republic one methodology how to compute and compare erosion risks. This methodology contain also method to design erosion control measures. The base of this methodology is Universal Soil Loss Equation (USLE) and their result long-term average annual rate of erosion (G). This methodology is used for landscape planners. Data and statistics from database of erosion events in the Czech Republic shows that many troubles and damages are from local episodes of erosion events. An extent of these events and theirs impact are conditional to local precipitation events, current plant phase and soil conditions. These erosion events can do troubles and damages on agriculture land, municipally property and hydro components and even in a location is from point of view long-term average annual rate of erosion in good conditions. Other way how to compute and compare erosion risks is episodes approach. In this paper is presented the compare of various approach to compute erosion risks. The comparison was computed to locality from database of erosion events on agricultural land in the Czech Republic where have been records two erosion events. The study area is a simple agriculture land without any barriers that can have high influence to water flow and soil sediment transport. The computation of erosion risks (for all methodology) was based on laboratory analysis of soil samples which was sampled on study area. Results of the methodology USLE, MUSLE and results from mathematical model Erosion 3D have been compared. Variances of the results in space distribution of the places with highest soil erosion where compared and discussed. Other part presents variances of design control erosion measures where their design was done on based different methodology. The results shows variance of computed erosion risks which was done by different methodology. These variances can start discussion about different approach how compute and evaluate erosion risks in areas

  19. Modelling soil erosion reduction by mahonia aquifolium on hillslopes in hungary: The impact of soil stabilization by roots

    NARCIS (Netherlands)

    Hudek, C.; Sterk, Geert; van Beek, Rens L P H; de Jong, Steven M.

    2014-01-01

    Agricultural activities on hillslopes often cause soil erosion and degradation. Permanent vegetation strips on cultivated slopes could be an effective soil conservation technique to reduce erosion. Previous studies showed that cultivated Mahonia aquifolium can be an effective plant for water erosion

  20. Job satisfaction of dental practitioners before and after a change in incentives and governance: a longitudinal study.

    Science.gov (United States)

    Harris, R; Burnside, G; Ashcroft, A; Grieveson, B

    2009-07-25

    to measure changes in dental practitioners' job satisfaction following a contractual change, and compare differences between those transferring from a fee-per-item system (general dental service, GDS) and those previously working under a block contract with the primary care trust (personal dental service, PDS). Analysis of postal questionnaires conducted in 2006 and 2007. Four hundred and forty dental practitioners responding to the 2006 baseline questionnaire. Although perceived workload was unchanged, global job satisfaction had decreased for 24.7% (31) of GDS dentists and 49.0% (95) of PDS dentists comparing their scores given before and after the contractual change. PDS dentists showed a significant change in attitudes towards feeling restricted in providing quality care (change in factor mean [SD] = -2.88 [0.82]; p private sector. The study indicates that the fall in job satisfaction is more a result of a perceived erosion of professional autonomy than a reaction to the change in the system of remuneration.

  1. Recovery of crystallographic texture in remineralized dental enamel.

    Science.gov (United States)

    Siddiqui, Samera; Anderson, Paul; Al-Jawad, Maisoon

    2014-01-01

    Dental caries is the most prevalent disease encountered by people of all ages around the world. Chemical changes occurring in the oral environment during the caries process alter the crystallography and microstructure of dental enamel resulting in loss of mechanical function. Little is known about the crystallographic effects of demineralization and remineralization. The motivation for this study was to develop understanding of the caries process at the crystallographic level in order to contribute towards a long term solution. In this study synchrotron X-ray diffraction combined with scanning electron microscopy and scanning microradiography have been used to correlate enamel crystallography, microstructure and mineral concentration respectively in enamel affected by natural caries and following artificial demineralization and remineralization regimes. In particular, the extent of destruction and re-formation of this complex structure has been measured. 2D diffraction patterns collected at the European Synchrotron Radiation Facility were used to quantify changes in the preferred orientation (crystallographic texture) and position of the (002) Bragg reflection within selected regions of interest in each tooth slice, and then correlated with the microstructure and local mineral mass. The results revealed that caries and artificial demineralization cause a large reduction in crystallographic texture which is coupled with the loss of mineral mass. Remineralization restores the texture to the original level seen in healthy enamel and restores mineral density. The results also showed that remineralization promotes ordered formation of new crystallites and growth of pre-existing crystallites which match the preferred orientation of healthy enamel. Combining microstructural and crystallographic characterization aids the understanding of caries and erosion processes and assists in the progress towards developing therapeutic treatments to allow affected enamel to regain

  2. Influence of metal dental materials on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi [Nippon Medical School, Tokyo (Japan). Main Hospital; Nakata, Minoru; Fujita, Isao

    1998-11-01

    Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

  3. Influence of metal dental materials on MR imaging

    International Nuclear Information System (INIS)

    Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi; Nakata, Minoru; Fujita, Isao

    1998-01-01

    Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

  4. A New Instrument for Testing Wind Erosion by Soil Surface Shape Change

    International Nuclear Information System (INIS)

    Hai, C.; Yuan, X.; Jiang, H.; Zhou, R.; Wang, J.; Liu, B.; Ye, Y.; Du, P.

    2010-01-01

    Wind erosion, a primary cause of soil degeneration, is a problem in arid and semiarid areas throughout the world. Many methods are available to study soil erosion, but there is no an effective method for making quantitative measurements in the field. To solve this problem, we have developed a new instrument that can measure the change in the shape of the soil surface, allowing quick quantification of wind erosion. In this paper, the construction and principle of the new instrument are described. Field experiments are carried out using the instrument, and the data are analyzed. The erosion depth is found to vary by 11% compared to the average for measurement areas ranging from 30 x 30 cm 2 to 10 x 10 cm 2 . The results show that the instrument is convenient and reliable for quantitatively measuring wind erosion in the field.

  5. New perspectives on the soil erosion-soil quality relationship

    International Nuclear Information System (INIS)

    Pennock, D.J.

    1998-01-01

    The redistribution of soil has a profound impact on its quality (defined as its ability to function within its ecosystem and within adjacent ecosystems) and ultimately on its productivity for crop growth. The application of 137 Cs-redistribution techniques to the study of erosion has yielded major new insights into the soil erosion-soil quality relationship. In highly mechanized agricultural systems, tillage erosion can be the dominant cause of soil redistribution; in other agroecosystems, wind and water erosion dominate. Each causal factor results in characteristic landscape-scale patterns of redistribution. In landscapes dominated by tillage redistribution, highest losses occur in shoulder positions (those with convex downslope curvatures); in water-erosion-dominated landscapes, highest losses occur where slope gradient and length are at a maximum. Major impacts occur through the loss of organically-enriched surface material and through the incorporation of possibly yield-limiting subsoils into the rooting zone of the soil column. The potential impact of surface soil losses and concomitant subsoil incorporation on productivity may be assessed by examining the pedological nature of the affected soils and their position in the landscape. The development of sound conservation policies requires that the soil erosion-quality relationship be rigorously examined in the full range of pedogenic environments, and future applications of the 137 Cs technique hold considerable promise for providing this comprehensive global database. (author)

  6. Distributed Modeling of soil erosion and deposition affected by buffer strips

    DEFF Research Database (Denmark)

    Khademalrasoul, Ataalah; Heckrath, Goswin Johann; Iversen, Bo Vangsø

    bodies. Buffer zones can be efficient in terms of retaining sediment and phosphorus transported by water erosion. This study aimed at parameterizing a spatial distributed erosion model to evaluate the effect of different buffer zone properties and dimension. It was our hypothesis that the placement...... was surveyed during the runoff season. In addition, organic carbon and phosphorous contents as well as bulk density were determined in soils of eroding and depositional sites. General buffer zone properties were recorded. Here we present results from scenario analyses comparing measured sediment deposition......Soil degradation and environmental impacts due to water erosion are a growing concern globally. Large parts of Denmark are covered by gently rolling moraine landscape with moderately to locally highly erodible soils where water erosion causes off-site problems in the form of eutrophication of water...

  7. Occupational contact dermatitis amongst dentists and dental technicians

    OpenAIRE

    Lugović-Mihić, Liborija; Ferček, Iva; Duvančić, Tomislav; Bulat, Vedrana; Ježovita, Josip; Novak-Bilić, Gaby; Šitum, Mirna

    2016-01-01

    Since the working medical personnel including dentists and dental technicians mainly use their hands, it is understandable that the most common occupational disease amongst medical personnel is contact dermatitis (CD) (80%-90% of cases). Development of occupational CD is caused by contact of the skin with various substances in occupational environment. Occupational etiologic factors for dental personnel are foremost reactions to gloves containing latex, followed by various dental materials...

  8. New approaches to the estimation of erosion-corrosion

    International Nuclear Information System (INIS)

    Bakirov, Murat; Ereemin, Alexandr; Levchuck, Vasiliy; Chubarov, Sergey

    2006-09-01

    Reliability safety and effectiveness of Russian and foreign power plants to a significant degree depend on erosion-corrosion durability of the equipment and pipelines, which work in single-phase and double-phase flows. Variety of failure mechanisms of metal equipment is determined phase conditions, thermodynamic, hydrodynamic, water-chemistry and other parameters of regimes. Analysis of statistic data about the damage in the main feed water pipe and of steam-water pipe and investigations in this field show, that the most of such work are fulfilled without taking into account the different mechanisms damaging the metal. Classification of failure mechanisms of metallic equipment, gave the possibility to select two groups of the destruction (failure) mechanisms of the metals: the first - which damages surface (reduction of thickness), the second - which breaks down inner structure of metals. Mechanism of erosion-corrosion of the metal is realized in single-phase and in double-phase steams (flows), and is widespread in operational circuits of NPPs. The results of erosion-corrosion influence are: reduction of thickness and as a final degree - failure of the power equipment elements, and after it failure of operational circuit of NPP. General corrosion becomes the main cause of a pollution of the working medium by the iron-containing compounds and of the deposits forming in steam generators and turbines. Local erosion-corrosion in single-phase flow can be accompanied by cavitational erosion, and in double-phase flow by drop-impact erosion. Erosion-corrosion should be understood as a physical-mechanical mechanism of destruction of the metal surface layer, accompanied, from one side, by formation of the protective oxide layer, and from the other side, by its dilution and removal into the main flow. Erosion-corrosion in the double-phase streams (flows) is a combination of the processes of corrosion and erosion components which progress at the same time. Principal feature of

  9. Tooth wear and erosion: methodological issues in epidemiological and public health research and the future research agenda.

    Science.gov (United States)

    Ganss, C; Young, A; Lussi, A

    2011-09-01

    This paper addresses methodological issues in the field of tooth wear and erosion research including the epidemiological indices, and identifies future work that is needed to improve knowledge about tooth wear and erosion. The paper is result of the work done at the meetings of the Special Interest Group "Tooth Surface Loss and Erosion" at the 2008, 2009 and 2010 conferences of the European Association for Dental Public Health, and the Workshop "Current Erosion indices- flawed or valid" which took place in Basel in 2007. Although there is consensus about the definition and the diagnostic criteria of various forms of tooth wear, gaps in research strategies have been identified. A basic problem is that fundamental concepts of wear and erosion as an oral health problem, have not yet been sufficiently defined. To a certain extent, tooth wear is a physiological condition, and there is no consensus as to whether it can be regarded as a disease. Furthermore, the multitude of indices and flaws in existing indices, make published data difficult to interpret. Topics for the research agenda are: the initiation of a consensus process towards an internationally accepted index, and the initiation of data collection on the prevalence of various forms of wear on a population-based level. There should be an emphasis on promoting communication between basic and clinical sciences, and the area of Public Health Dentistry. Furthermore, the question of whether tooth wear is a public health problem remains open for debate.

  10. Modeling the Contribution of Ephemeral Gully Erosion Under Different Soil Management in An Olive Orchard Microcatchment Using AnnAGNPS Model

    Science.gov (United States)

    In Spain, few studies have been carried out to explore the erosion caused by processes other than interrill and rill erosion, such as gully and ephemeral gully erosion, especially because most of the available studies have evaluated the erosion at plot scale. A study about the en...

  11. Divertor tungsten tiles erosion in the region of the castellated gaps

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Wanpeng, E-mail: wangdez@dlut.edu.cn; Sang, Chaofeng; Sun, Zhenyue; Wang, Dezhen

    2016-11-01

    Highlights: • Simulation of the tungsten tiles erosion by different impurities in the divertor gap region is done by using a 2d3v Particle-In-Cell code. • High-Z impurity causes the largest erosion rate on W tile. • The peak physical sputtering erosion rate locates at the plasma-facing corners. - Abstract: Erosion of tungsten (W) is a very important issue for the future fusion device. The castellated divertor makes it more complicated due to complex geometry of the gap between the tiles. In this work, the plasma behaviors and resulting W tile erosion in the divertor tile gap region are studied by using a two dimension-in-space and three dimension-in-velocity (2d3 v) Particle-In-Cell (PIC) code. Deuterium ions (D{sup +}) and electrons are traced self-consistently in the simulation to provide the plasma background. Since there are lots of impurities, which may make a great impact on the tile erosion, in the divertor region to radiate the power, the erosion of W tile by different species are thus considered. The contributions of deuterium and impurities: Li, C, Ne, and Ar, to the W erosion, are studied under EAST conditions to show a straightforward insight. It is observed that the physical sputtering of W tile by impurities is much higher than that by the D ions, and the peak erosion region locates at the plasma-facing corners.

  12. Remote sensing monitoring on soil erosion based on LUCC in Beijing mountain areas

    International Nuclear Information System (INIS)

    Gaiying, Chen

    2014-01-01

    The eco-environmental problems caused by land use and land cover change have been a severe block to regional sustainable development in the Beijing mountain areas. In this study, two temporal Landsat TM images in 2002 and 2009 were used, the soil erosion factors included vegetation coverage, slope and land use were calculated. The soil erosion degree was divided into six levels, micro, mild, moderate, strong, intensive and severe. The raster data with 30 m × 30 m pixels small-class of the soil erosion map was used to extract soil erosion information. This thesis evaluated soil erosion dynamic in Beijing mountain areas based on land use and land cover change with the combination of technologies and methodologies of multi-temporal satellite remote sensing, GIS and field investigation. The soil erosion change and their driving forces were analysed. The results showed micro and mild soil erosion mainly existed in the Beijing mountain areas. The moderate erosion emerged in the areas with both slope and poor vegetation cover. The strong, intensive and severe soil erosion were rare but distributed in mountainous areas in Huairou, Miyun, and Mentougou. The soil erosion situation has improved markedly due to environment management from 2002 to 2009

  13. Mesh erosion after abdominal sacrocolpopexy.

    Science.gov (United States)

    Kohli, N; Walsh, P M; Roat, T W; Karram, M M

    1998-12-01

    To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management.

  14. Mind the gap! A comparison of oral health knowledge between dental, healthcare professionals and the public.

    Science.gov (United States)

    Richards, W; Filipponi, T; Roberts-Burt, V

    2014-02-01

    The importance of consistent, accurate and unambiguous messages are well documented in oral health promotion literature. Whether the reality of delivering messages in the field fulfils these principle is questionable. This paper explores the perceptions of dental professionals, healthcare professionals and lay community members with regard to key oral health messages in order to highlight any inconsistencies and knowledge gaps between and within groups for disease risk factors. A questionnaire was administered to individuals who belonged to three groups: dental professionals, healthcare professionals and lay community members. The questionnaire established knowledge regarding risk factors for caries, periodontal disease and erosion. Thirty-five (57.4%) of the dental group answered the whole questionnaire correctly, with 22 (27.8%) and 9 (5.1%) of the healthcare and lay community group answering the whole questionnaire correctly, respectively. The question of fluoride levels in children's toothpaste was the main reason for incorrect answers in the dental group. The results of this survey demonstrate a knowledge gradient from dental professionals through to healthcare professionals and then to lay members of the community. The knowledge base observed in the dental group is reflected in the other two groups as would be expected albeit with a significant gap between each group. As expected the dental professionals are generally well informed, but not as well informed as could be expected.

  15. Erosion of the 4-6- and 8 group transition metals under intense laser radiation

    International Nuclear Information System (INIS)

    Samsonov, G.V.; Verkhoturov, A.D.; Roshchina, A.I.; Vasil'ev, A.V.; Klimenko, V.P.

    1976-01-01

    The erosion resistance is studied of transition metals of Groups 4-6 and 8 at laser emission of approximately 6x1O 7 W/cm 2 . It is shown that as the emission power increases from 10 6 to 6x10 7 W/cm 2 the erosion values show an increase over tenfold without any subsequent filling of the craters. The growth of the metallic erosion is largely caused by a greater crater diameter. The erosion resistance of metals enhances in the following series: Ti-Zr-Co-Ni-Fe, Hf-V-Nb-Mo-Cr-Ta-W-Cu

  16. Microcomputed tomography-based assessment of retrieved dental implants

    NARCIS (Netherlands)

    Narra, N.; Antalainen, A.K.; Zipprich, H.; Sándor, G.K.; Wolff, J.

    2015-01-01

    Purpose: The aim of this study was to demonstrate the potential of microcomputed tomography (micro-CT) technology in the assessment of retrieved dental implants. Cases are presented to illustrate the value of micro-CT imaging techniques in determining possible mechanical causes for dental implant

  17. Dental complications of gastro-oesophageal reflux disease: guidance for physicians.

    Science.gov (United States)

    Lee, Robert J; Aminian, Amin; Brunton, Paul

    2017-06-01

    There is potential for gastro-oesophageal reflux disease (GORD) to be under-diagnosed by physicians. A quick, focused examination, requiring no special equipment, of a patients' dentition can assist in making a more accurate diagnosis where GORD is suspected. Guidance is provided for physicians as to what intra-oral signs are suggestive of intrinsic dental erosion, which is a clinical feature of GORD and its associated conditions. Use of this information will, it is suggested, improve outcomes for patients where GORD is suspected. © 2016 Royal Australasian College of Physicians.

  18. Spectrally enhanced imaging of occlusal surfaces and artificial shallow enamel erosions with a scanning fiber endoscope

    Science.gov (United States)

    Zhang, Liang; Nelson, Leonard Y.; Seibel, Eric J.

    2012-07-01

    An ultrathin scanning fiber endoscope, originally developed for cancer diagnosis, was used to image dental occlusal surfaces as well as shallow artificially induced enamel erosions from human extracted teeth (n=40). Enhanced image resolution of occlusal surfaces was obtained using a short-wavelength 405-nm illumination laser. In addition, artificial erosions of varying depths were also imaged with 405-, 404-, 532-, and 635-nm illumination lasers. Laser-induced autofluorescence images of the teeth using 405-nm illumination were also obtained. Contrast between sound and eroded enamel was quantitatively computed for each imaging modality. For shallow erosions, the image contrast with respect to sound enamel was greatest for the 405-nm reflected image. It was also determined that the increased contrast was in large part due to volume scattering with a smaller component from surface scattering. Furthermore, images obtained with a shallow penetration depth illumination laser (405 nm) provided the greatest detail of surface enamel topography since the reflected light does not contain contributions from light reflected from greater depths within the enamel tissue. Multilayered Monte Carlo simulations were also performed to confirm the experimental results.

  19. Dental Calculus Arrest of Dental Caries

    OpenAIRE

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human t...

  20. Dental restorative materials from a work environmental perspective

    OpenAIRE

    Lönnroth, Emma-Christin

    1999-01-01

    The main occupational health hazard for dental personnel is muscle-skeletal problem, followed by symptoms caused by exposure to chemicals. Clinical dental work includes exposure to a number of products like soap, detergents, disinfectants, amalgam, mono- and oligomers, catalysts, inhibitors, solvents and adhesives. Some are chemically very active. The aims of this thesis have been to survey the occurrence of symptoms from skin, eyes and respiratory tract among dental personnel working in gene...

  1. Orofacial piercings: perceptions of dental practitioners and piercing parlours.

    Science.gov (United States)

    Chadwick, Barbara L; Groves, Gemma; Dransfield, Kathryn

    2005-07-01

    To identify the advice given by piercing parlours prior to orofacial piercing and to determine how many dental practitioners see complications from orofacial piercings. Administered questionnaire to 19 piercing parlours and postal questionnaire to 400 dental practitioners in south-east Wales. Ninety-nine per cent of 227 dental practitioners in south-east Wales had treated patients with orofacial piercings, over three-quarters had seen a patient for a complication caused by the piercing, and over half (N=120) had treated a patient for a complication of piercing. Tongue (N=225) and lip (N=209) piercings were most frequently seen and the most commonly occurring complication was fractured or cracked teeth (N=176). Almost all practitioners wanted more information on orofacial piercing and its sequelae. All 19 piercing parlours in south-east Wales warned clients about pain following piercing and 18 mentioned swelling; only four discussed possible damage to teeth and none discussed the risk of airway obstruction. Despite the concerns of dental and medical professionals orofacial piercing remains popular and the complications it causes are frequently seen by dental practitioners. There is a need for literature to assist both dental practitioners and piercers in advising and safeguarding patients.

  2. Protection from erosion following wildfire

    Science.gov (United States)

    Peter R. Robichaud; William J. Elliot

    2006-01-01

    Erosion in the first year after a wildfire can be up to three orders of magnitude greater than the erosion from undisturbed forests. To mitigate potential postfire erosion, various erosion control treatments are applied on highly erodible areas with downstream resources in need of protection. Because postfire erosion rates generally decline by an order of magnitude for...

  3. An Establishment of Rainfall-induced Soil Erosion Index for the Slope Land in Watershed

    Science.gov (United States)

    Tsai, Kuang-Jung; Chen, Yie-Ruey; Hsieh, Shun-Chieh; Shu, Chia-Chun; Chen, Ying-Hui

    2014-05-01

    With more and more concentrated extreme rainfall events as a result of climate change, in Taiwan, mass cover soil erosion occurred frequently and led to sediment related disasters in high intensity precipiton region during typhoons or torrential rain storms. These disasters cause a severely lost to the property, public construction and even the casualty of the resident in the affected areas. Therefore, we collected soil losses by using field investigation data from the upstream of watershed where near speific rivers to explore the soil erosion caused by heavy rainfall under different natural environment. Soil losses induced by rainfall and runoff were obtained from the long-term soil depth measurement of erosion plots, which were established in the field, used to estimate the total volume of soil erosion. Furthermore, the soil erosion index was obtained by referring to natural environment of erosion test plots and the Universal Soil Loss Equation (USLE). All data collected from field were used to compare with the one obtained from laboratory test recommended by the Technical Regulation for Soil and Water Conservation in Taiwan. With MATLAB as a modeling platform, evaluation model for soil erodibility factors was obtained by golden section search method, considering factors contributing to the soil erosion; such as degree of slope, soil texture, slope aspect, the distance far away from water system, topography elevation, and normalized difference vegetation index (NDVI). The distribution map of soil erosion index was developed by this project and used to estimate the rainfall-induced soil losses from erosion plots have been established in the study area since 2008. All results indicated that soil erodibility increases with accumulated rainfall amount regardless of soil characteristics measured in the field. Under the same accumulated rainfall amount, the volume of soil erosion also increases with the degree of slope and soil permeability, but decreases with the

  4. The Phenomenon of Dental Fear

    DEFF Research Database (Denmark)

    Moore, Rod

    Odontophobia is a rather unique phobia with special psychosomatic components that impact on the dental health of odontophobic persons. It also has psychosocial components largely as a result of destruction of the teeth and subsequent embarrassment that can affect a person and cause a vicious cycle...... of dental fear (see fig. 1). The phenomenon is facilitated by misunderstandings and myths generated by both patients and dentists (see table 1 for examples). The most common reasons given in the literature for such strong fears of dental treatment are: 1) bad experiences in childhood for 85% of cases, 2......) feeling of powerlessness and lack of control over personal emotional reactions and over the social situation in the dental chair, 3) social learning processes in which the image of the dentist is cast in a negative light by the mass media or by the person's relatives or friends and 4) that the person has...

  5. A history of wind erosion prediction models in the United States Department of Agriculture prior to the Wind Erosion Prediction System

    Science.gov (United States)

    Tatarko, John; Sporcic, Michael A.; Skidmore, Edward L.

    2013-09-01

    The Great Plains experienced an influx of settlers in the late 1850s-1900. Periodic drought was hard on both settlers and the soil and caused severe wind erosion. The period known as the Dirty Thirties, 1931-1939, produced many severe windstorms, and the resulting dusty sky over Washington, DC helped Hugh Hammond Bennett gain political support for the Soil Conservation Act of 1937 that started the USDA Soil Conservation Service (SCS). Austin W. Zingg and William S. Chepil began wind erosion studies at a USDA laboratory at Kansas State University in 1947. Neil P. Woodruff and Francis H. Siddoway published the first widely used model for wind erosion in 1965, called the Wind Erosion Equation (WEQ). The WEQ was solved using a series of charts and lookup tables. Subsequent improvements to WEQ included monthly magnitudes of the total wind, a computer version of WEQ programmed in FORTRAN, small-grain equivalents for range grasses, tillage systems, effects of residue management, crop row direction, cloddiness, monthly climate factors, and the weather. The SCS and the Natural Resources Conservation Service (NRCS) produced several computer versions of WEQ with the goal of standardizing and simplifying it for field personnel including a standalone version of WEQ was developed in the late 1990s using Microsoft Excel. Although WEQ was a great advancement to the science of prediction and control of wind erosion on cropland, it had many limitations that prevented its use on many lands throughout the United States and the world. In response to these limitations, the USDA developed a process-based model know as the Wind Erosion Prediction System (WEPS). The USDA Agricultural Research Service has taken the lead in developing science and technology for wind erosion prediction.

  6. THE USE OF BIOTEXTILES TO RECUPERATE DEGRADADED AREAS BY EROSION

    OpenAIRE

    Marcia Silva Furtado; Neilianne de Fátima Costa Lima; Ulisses Denache Vieira Souza; Jane Karina Silva Mendonça; Antônio Teixeira Guerra; Antonio Cordeiro Feitosa

    2005-01-01

    The erosion is a process that results from the conjunct action of many natural agents over the grounds. However, this process can be accelerated, mainly by the action of the human being that has caused numerous degrading actions of the environment, depending on the level of intensity and from the characteristic of his intervention. Among the ways of degradation it is possible to stand out accelerated erosive processes, like ravines and gullies.These processes can be mitigated with the use of ...

  7. Wind Erosion Induced Soil Degradation in Northern China: Status, Measures and Perspective

    Directory of Open Access Journals (Sweden)

    Zhongling Guo

    2014-12-01

    Full Text Available Soil degradation is one of the most serious ecological problems in the world. In arid and semi-arid northern China, soil degradation predominantly arises from wind erosion. Trends in soil degradation caused by wind erosion in northern China frequently change with human activities and climatic change. To decrease soil loss by wind erosion and enhance local ecosystems, the Chinese government has been encouraging residents to reduce wind-induced soil degradation through a series of national policies and several ecological projects, such as the Natural Forest Protection Program, the National Action Program to Combat Desertification, the “Three Norths” Shelter Forest System, the Beijing-Tianjin Sand Source Control Engineering Project, and the Grain for Green Project. All these were implemented a number of decades ago, and have thus created many land management practices and control techniques across different landscapes. These measures include conservation tillage, windbreak networks, checkerboard barriers, the Non-Watering and Tube-Protecting Planting Technique, afforestation, grassland enclosures, etc. As a result, the aeolian degradation of land has been controlled in many regions of arid and semiarid northern China. However, the challenge of mitigating and further reversing soil degradation caused by wind erosion still remains.

  8. Synchrotron-radiation-based X-ray micro-computed tomography reveals dental bur debris under dental composite restorations.

    Science.gov (United States)

    Hedayat, Assem; Nagy, Nicole; Packota, Garnet; Monteith, Judy; Allen, Darcy; Wysokinski, Tomasz; Zhu, Ning

    2016-05-01

    Dental burs are used extensively in dentistry to mechanically prepare tooth structures for restorations (fillings), yet little has been reported on the bur debris left behind in the teeth, and whether it poses potential health risks to patients. Here it is aimed to image dental bur debris under dental fillings, and allude to the potential health hazards that can be caused by this debris when left in direct contact with the biological surroundings, specifically when the debris is made of a non-biocompatible material. Non-destructive micro-computed tomography using the BioMedical Imaging & Therapy facility 05ID-2 beamline at the Canadian Light Source was pursued at 50 keV and at a pixel size of 4 µm to image dental bur fragments under a composite resin dental filling. The bur's cutting edges that produced the fragment were also chemically analyzed. The technique revealed dental bur fragments of different sizes in different locations on the floor of the prepared surface of the teeth and under the filling, which places them in direct contact with the dentinal tubules and the dentinal fluid circulating within them. Dispersive X-ray spectroscopy elemental analysis of the dental bur edges revealed that the fragments are made of tungsten carbide-cobalt, which is bio-incompatible.

  9. Assessment of mercury erosion by surface water in Wanshan mercury mining area.

    Science.gov (United States)

    Dai, ZhiHui; Feng, Xinbin; Zhang, Chao; Shang, Lihai; Qiu, Guangle

    2013-08-01

    Soil erosion is a main cause of land degradation, and in its accelerated form is also one of the most serious ecological environmental problems. Moreover, there are few studies on migration of mercury (Hg) induced by soil erosion in seriously Hg-polluted districts. This paper selected Wanshan Hg mining area, SW China as the study area. Revised universal soil loss equation (RUSLE) and Geographic information system (GIS) methods were applied to calculate soil and Hg erosion and to classify soil erosion intensity. Our results show that the soil erosion rate can reach up to 600,884tkm(-2)yr(-1). Surfaces associated with very slight and extremely severe erosion include 76.6% of the entire land in Wanshan. Furthermore, the cumulative erosion rates in the area impacted by extremely severe erosion make up 90.5% of the total. On an annual basis, Hg surface erosion load was predicted to be 505kgyr(-1) and the corresponding mean migration flux of Hg was estimated to be 3.02kgkm(-2)yr(-1). The erosion loads of Hg resulting from farmland and meadow soil were 175 and 319kgyr(-1) respectively, which were enhanced compared to other landscape types due to the fact that they are generally located in the steep zones associated with significant reclamation. Contributing to establish a mass balance of Hg in Wanshan Hg mining area, this study supplies a dependable scientific basis for controlling soil and water erosion in the local ecosystems. Land use change is the most effective way for reducing Hg erosion load in Wanshan mining area. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Evaluation of compost blankets for erosion control from disturbed lands.

    Science.gov (United States)

    Bhattarai, Rabin; Kalita, Prasanta K; Yatsu, Shotaro; Howard, Heidi R; Svendsen, Niels G

    2011-03-01

    Soil erosion due to water and wind results in the loss of valuable top soil and causes land degradation and environmental quality problems. Site specific best management practices (BMP) are needed to curb erosion and sediment control and in turn, increase productivity of lands and sustain environmental quality. The aim of this study was to investigate the effectiveness of three different types of biodegradable erosion control blankets- fine compost, mulch, and 50-50 mixture of compost and mulch, for soil erosion control under field and laboratory-scale experiments. Quantitative analysis was conducted by comparing the sediment load in the runoff collected from sloped and tilled plots in the field and in the laboratory with the erosion control blankets. The field plots had an average slope of 3.5% and experiments were conducted under natural rainfall conditions, while the laboratory experiments were conducted at 4, 8 and 16% slopes under simulated rainfall conditions. Results obtained from the field experiments indicated that the 50-50 mixture of compost and mulch provides the best erosion control measures as compared to using either the compost or the mulch blanket alone. Laboratory results under simulated rains indicated that both mulch cover and the 50-50 mixture of mulch and compost cover provided better erosion control measures compared to using the compost alone. Although these results indicate that the 50-50 mixtures and the mulch in laboratory experiments are the best measures among the three erosion control blankets, all three types of blankets provide very effective erosion control measures from bare-soil surface. Results of this study can be used in controlling erosion and sediment from disturbed lands with compost mulch application. Testing different mixture ratios and types of mulch and composts, and their efficiencies in retaining various soil nutrients may provide more quantitative data for developing erosion control plans. Copyright © 2010 Elsevier

  11. Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

    Science.gov (United States)

    Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

    2013-11-01

    This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil.

  12. Estimating soil erosion risk and evaluating erosion control measures for soil conservation planning at Koga watershed in the highlands of Ethiopia

    Science.gov (United States)

    Molla, Tegegne; Sisheber, Biniam

    2017-01-01

    Soil erosion is one of the major factors affecting sustainability of agricultural production in Ethiopia. The objective of this paper is to estimate soil erosion using the universal soil loss equation (RUSLE) model and to evaluate soil conservation practices in a data-scarce watershed region. For this purpose, soil data, rainfall, erosion control practices, satellite images and topographic maps were collected to determine the RUSLE factors. In addition, measurements of randomly selected soil and water conservation structures were done at three sub-watersheds (Asanat, Debreyakob and Rim). This study was conducted in Koga watershed at upper part of the Blue Nile basin which is affected by high soil erosion rates. The area is characterized by undulating topography caused by intensive agricultural practices with poor soil conservation practices. The soil loss rates were determined and conservation strategies have been evaluated under different slope classes and land uses. The results showed that the watershed is affected by high soil erosion rates (on average 42 t ha-1 yr-1), greater than the maximum tolerable soil loss (18 t ha-1 yr-1). The highest soil loss (456 t ha-1 yr-1) estimated from the upper watershed occurred on cultivated lands of steep slopes. As a result, soil erosion is mainly aggravated by land-use conflicts and topographic factors and the rugged topographic land forms of the area. The study also demonstrated that the contribution of existing soil conservation structures to erosion control is very small due to incorrect design and poor management. About 35 % out of the existing structures can reduce soil loss significantly since they were constructed correctly. Most of the existing structures were demolished due to the sediment overload, vulnerability to livestock damage and intense rainfall. Therefore, appropriate and standardized soil and water conservation measures for different erosion-prone land uses and land forms need to be implemented in Koga

  13. Reduction of surface erosion caused by helium blistering in sintered beryllium and sintered aluminum powder

    International Nuclear Information System (INIS)

    Das, S.K.; Kaminsky, M.

    1976-01-01

    Studies have been conducted to find materials with microstructures which minimize the formation of blisters. A promising class of materials appears to be sintered metal powder with small average grain sizes and low atomic number Z. Studies of the surface erosion of sintered aluminum powder (SAP 895) and of aluminum held at 400 0 C due to blistering by 100 keV helium ions have been conducted and the results are compared to those obtained earlier for room temperature irradiation. A significant reduction of the erosion rate in SAP 895 in comparison to annealed aluminum and SAP 930 is observed. In addition results on the blistering of sintered beryllium powder (type I) irradiated at room temperature and 600 0 C by 100 keV helium ions are given. These results will be compared with those reported recently for vacuum cast beryllium foil and a foil of sintered beryllium powder (type II) which was fabricated differently, than type I. For room temperature irradiation only a few blisters could be observed in sintered beryllium powder type I and type II and they are smaller in size and in number than in vacuum cast beryllium. For irradiation at 600 0 C large scale exfoliation of blisters was observed for vacuum cast beryllium but much less exfoliation was seen for sintered beryllium powder, type I, and type II. The results show a reduction in erosion rate cast beryllium, for both room temperature and 600 0 C

  14. DENTAL WEAR CAUSED BY ASSOCIATION BETWEEN BRUXISM AND GASTROESOPHAGEAL REFLUX DISEASE: A REHABILITATION REPORT

    OpenAIRE

    Machado, Naila Aparecida de Godoi; Fonseca, Rodrigo Borges; Branco, Carolina Assaf; Barbosa, Gustavo Augusto Seabra; Fernandes, Alfredo J?lio; Soares, Carlos Jos?

    2007-01-01

    Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related str...

  15. Atomic force microscopy analysis of different surface treatments of Ti dental implant surfaces

    International Nuclear Information System (INIS)

    Bathomarco, R.V.; Solorzano, G.; Elias, C.N.; Prioli, R.

    2004-01-01

    The surface of commercial unalloyed titanium, used in dental implants, was analyzed by atomic force microscopy. The morphology, roughness, and surface area of the samples, submitted to mechanically-induced erosion, chemical etching and a combination of both, were compared. The results show that surface treatments strongly influence the dental implant physical and chemical properties. An analysis of the length dependence of the implant surface roughness shows that, for scan sizes larger than 50 μm, the average surface roughness is independent of the scanning length and that the surface treatments lead to average surface roughness in the range of 0.37 up to 0.48 μm. It is shown that the implant surface energy is sensitive to the titanium surface area. As the area increases there is a decrease in the surface contact angle

  16. Atomic force microscopy analysis of different surface treatments of Ti dental implant surfaces

    Science.gov (United States)

    Bathomarco, Ti R. V.; Solorzano, G.; Elias, C. N.; Prioli, R.

    2004-06-01

    The surface of commercial unalloyed titanium, used in dental implants, was analyzed by atomic force microscopy. The morphology, roughness, and surface area of the samples, submitted to mechanically-induced erosion, chemical etching and a combination of both, were compared. The results show that surface treatments strongly influence the dental implant physical and chemical properties. An analysis of the length dependence of the implant surface roughness shows that, for scan sizes larger than 50 μm, the average surface roughness is independent of the scanning length and that the surface treatments lead to average surface roughness in the range of 0.37 up to 0.48 μm. It is shown that the implant surface energy is sensitive to the titanium surface area. As the area increases there is a decrease in the surface contact angle.

  17. Effects of dental materials on MR images

    International Nuclear Information System (INIS)

    Hinshaw, D.B. Jr.; Hoishouser, B.; Engstrom, H.

    1986-01-01

    As MR imaging of the head and neck area becomes increasingly important in evaluating pathologic conditions of the brain, mid-face, and pharynx, it is becoming apparent that artifacts due to certain dental materials can obscure the findings. Although this fact has been known for some time, a study to identify which materials produce artifacts has not been performed. The authors examined the degree of artifact production caused by various materials commonly used in dental restorations. Since not all dental materials produce artifacts during MR imaging, these materials are described also

  18. Modelling Soil Erosion in the Densu River Basin Using RUSLE and GIS Tools.

    Science.gov (United States)

    Ashiagbori, G; Forkuo, E K; Laari, P; Aabeyir, R

    2014-07-01

    Soil erosion involves detachment and transport of soil particles from top soil layers, degrading soil quality and reducing the productivity of affected lands. Soil eroded from the upland catchment causes depletion of fertile agricultural land and the resulting sediment deposited at the river networks creates river morphological change and reservoir sedimentation problems. However, land managers and policy makers are more interested in the spatial distribution of soil erosion risk than in absolute values of soil erosion loss. The aim of this paper is to model the spatial distribution of soil erosion in Densu River Basin of Ghana using RUSLE and GIS tools and to use the model to explore the relationship between erosion susceptibility, slope and land use/land cover (LULC) in the Basin. The rainfall map, digital elevation model, soil type map, and land cover map, were input data in the soil erosion model developed. This model was then categorized into four different erosion risk classes. The developed soil erosion map was then overlaid with the slope and LULC maps of the study area to explore their effects on erosion susceptibility of the soil in the Densu River Basin. The Model, predicted 88% of the basin as low erosion risk and 6% as moderate erosion risk, 3% as high erosion risk and 3% as severe risk. The high and severe erosion areas were distributed mainly within the areas of high slope gradient and also sections of the moderate forest LULC class. Also, the areas within the moderate forest LULC class found to have high erosion risk, had an intersecting high erodibility soil group.

  19. Internal erosion under spillway rested on an embankment dam

    Directory of Open Access Journals (Sweden)

    Mohammad Sedghi-Asl

    2015-12-01

    Full Text Available In this paper we investigate the mechanism of internal erosion caused in the right abutment of the Shahghasem dam’s spillway. Shahghasem dam is an earthen dam located in Yasouj, in southwest of Iran. A significant hole and pipe have been observed in the corner of the right abutment from upstream view. The foundation is Marlstone, which has low cohesion and susceptible for internal erosion and piping in some conditions. Going through details of the design maps has shown that Lane’s criteria for selecting safe dimensions of the seepage control measures have not been considered properly. A series of the supportive walls are designed to attach to the right part of the spillway in order to increase the length of seepage. The pipe route of the erosion should also be grouted with high quality concrete.

  20. Evaluating ephemeral gully erosion impact on Zea mays L. yield and economics using AnnAGNPS

    Science.gov (United States)

    Ephemeral gully erosion causes serious water quality and economic problems in the Midwest United States. A critical barrier to soil conservation practice adoption is often the implementation cost, although it is recognized that erosion reduces farm income. Yet few, if any, understand the relationshi...

  1. Dental Fear in Children with Repeated Tooth Injuries.

    Science.gov (United States)

    Negovetić Vranić, Dubravka; Ivančić Jokić, Nataša; Bakarčić, Danko; Carek, Andreja; Rotim, Željko; Verzak, Željko

    2016-06-01

    Tooth injuries are serious clinical conditions. Some children experience dental trauma only once, while others are more prone to repeated tooth injuries. Repeated dental trauma occurs in 19.4% to 30% of patients. Pain and dental trauma are the most common reasons for fear and anxiety. The main objective of this study was to investigate how dental trauma, as well as repeated dental trauma affects the occurrence and development of dental fear in children. The study was conducted on a random sample of 147 subjects (88 boys and 59 girls) aged 5-8 and 9-12 years. Subjects in both age groups were divided into subroups without dental trauma, with one dental trauma and with repeated dental trauma. The validated Children’s Fear Survey Schedule – Dental Subscale was used on fear assessment. Results showed that only 12.2% of children without trauma, 33.3% with one trauma and 51.7% with repeated trauma were not afraid of injection. Older children had a significantly lower fear of injections, touch of an unknown person, choking, going to the hospital and people in white uniforms. Dentist was not the cause of fear in 65.5% of patients with repeated trauma. With each repeated injury of teeth, the degree of their fear of dental treatment was lower.

  2. Heartburn, gastro-oesophageal reflux disease and non-erosive ...

    African Journals Online (AJOL)

    Heartburn, gastro-oesophageal reflux disease and non-erosive reflux disease. Haley Smith. Abstract. Reflux is a normal process that occurs in healthy infants, children and adults. Most episodes are short-lived and do not cause bothersome symptoms of complications. Gastro-oesophageal reflux disease (GORD) develops ...

  3. Mapping erosion from space

    NARCIS (Netherlands)

    Vrieling, A.

    2007-01-01

    Soil erosion by water is the most important land degradation problem worldwide. Spatial information on erosion is required for defining effective soil and water conservation strategies. Satellite remote sensing can provide relevant input to regional erosion assessment. This thesis comprises a review

  4. First mirror deposition/erosion experiment by using multi-purpose manipulators in KSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Suk-Ho, E-mail: sukhhong@nfri.re.kr [National Fusion Research Institute, Daejeon (Korea, Republic of); University of Science and Technology, Daejeon (Korea, Republic of); Department of Electrical Engineering, Hanyang University, Seoul (Korea, Republic of); Bang, Eunnam; Son, Soohyun [National Fusion Research Institute, Daejeon (Korea, Republic of); Kogut, Dmitry; Douai, David [CEA, IRFM, Association Euratom-CEA, Paul lez Durance (France)

    2016-11-01

    First mirrors are essential plasma-facing components (PFCs) for fusion devices. Erosion and redeposition on first mirrors are of interest, since they cause degradation of signal intensity. In order to trace deposition/erosion characteristics of amorphous hydrogenated carbon (a-C:H) films on first mirrors, two manipulators attached at midplane and divertor regions of KSTAR vacuum vessel are utilized. A net deposition rate of 0.3–0.5 nm/s during a discharge and an erosion rates of 0.1 nm/s during He ion cyclotron wall conditioning (ICWC) are obtained. Property of redeposited layers are different depending on the location, varying from soft polymer-like to hard diamond-like a-C:H layers. For the deposition and erosion of metal layers, a plan for a dedicated experimental session has been set at KSTAR.

  5. First mirror deposition/erosion experiment by using multi-purpose manipulators in KSTAR

    International Nuclear Information System (INIS)

    Hong, Suk-Ho; Bang, Eunnam; Son, Soohyun; Kogut, Dmitry; Douai, David

    2016-01-01

    First mirrors are essential plasma-facing components (PFCs) for fusion devices. Erosion and redeposition on first mirrors are of interest, since they cause degradation of signal intensity. In order to trace deposition/erosion characteristics of amorphous hydrogenated carbon (a-C:H) films on first mirrors, two manipulators attached at midplane and divertor regions of KSTAR vacuum vessel are utilized. A net deposition rate of 0.3–0.5 nm/s during a discharge and an erosion rates of 0.1 nm/s during He ion cyclotron wall conditioning (ICWC) are obtained. Property of redeposited layers are different depending on the location, varying from soft polymer-like to hard diamond-like a-C:H layers. For the deposition and erosion of metal layers, a plan for a dedicated experimental session has been set at KSTAR.

  6. Chilean Dentistry students, levels of empathy and empathic erosion: Necessary evaluation before a planned intervention

    Directory of Open Access Journals (Sweden)

    Víctor Patricio Díaz-Narváez

    2018-04-01

    Full Text Available Objectives: To estimate the general empathy levels and the potential for empathic growth in Dentistry students and demonstrate that the empathic erosion model is not med. Material and methods: Exploratory and cross-sectional study. Population: First- to fifth-year Dentistry students at Universidad San Sebastián, Santiago Campus (Chile. The total student population (N was 800. The participants completed the Jefferson Scale of Empathy in its Spanish version for medical students, validated and adapted in Chile. A two-factor analysis of variance (model III was applied to find differences in the means between academic years, between genders, and in the interaction between these two factors. The data were described using simple arithmetic graphs and then processed with SPSS 22.0. The total growth potential was estimated. Results: The Sample (n consisted of 534 students (66.88% of the population studied, 2016. Differences were found between academic years and genders in general empathy and some of its components. Conclusion: The behavior of empathy levels is not in line with the concept of empathic erosion. This suggests that empathic erosion is a particular and not a general phenomenon. There exists a considerable growth potential for empathy and its components. Keywords: Empathy, Dental student, Empathic evaluation

  7. Environmental and perceived stress in Australian dental undergraduates: Preliminary outcomes

    Directory of Open Access Journals (Sweden)

    Shannon Astill

    2016-12-01

    Full Text Available Background. Dental students have reported a high prevalence of psychological stress and the causes are associated with the challenging dental environmental and demographic factors. This study aimed to conduct a preliminary investigation on dental students’ stress status, using a sample of first-to-third-year Bachelor of Dental Surgery students in an Australian university. Special interests included causes of dental environmental stress and access to help services. Methods. A sample of 145 students was surveyed with a modified Dental Environmental Survey and Depression Anxiety Stress Scale in 2014. The participants’ demographic information was also collected. Results. The response rate was 95.4%. Second-year (P = 0.042, third-year (P < 0.001 and employed students (P = 0.027 were more likely to report stress resulting from transition to clinical learning. Third-year students were more often stressed about communicating and approaching staff (P = 0.023 as well as different opinions between staff (P < 0.001 and reduced holidays (P < 0.001. Students that were younger than 21 years of age (P = 0.001, that were first years (P < 0.001, and that were not in a relationship (P = 0.010 more often found difficulty of course work stressful. Students who were not in a relationship more often considered learning manual dexterity a source of stress (P = 0.034. Students previously seeking professional help were more likely to be stressed (P = 0.010. Conclusion. Causes of dental environment stress varied among years of study and demographic backgrounds. Professional support to stressed students should be enhanced. Further investigation is indicated.

  8. Dental caries in Victorian nursing homes.

    Science.gov (United States)

    Silva, M; Hopcraft, M; Morgan, M

    2014-09-01

    The poor oral health of nursing home residents is the cause of substantial morbidity and has major implications relating to health care policy. The aim of this study was to measure dental caries experience in Australians living in nursing homes, and investigate associations with resident characteristics. Clinical dental examinations were conducted on 243 residents from 19 nursing homes in Melbourne. Resident characteristics were obtained from nursing home records and interviews with residents, family and nursing home staff. Two dental examiners assessed coronal and root dental caries using standard ICDAS-II criteria. Residents were elderly, medically compromised and functionally impaired. Most required assistance with oral hygiene and professional dental care was rarely utilized. Residents had high rates of coronal and root caries, with a mean 2.8 teeth with untreated coronal caries and 5.0 root surfaces with untreated root caries. Functional impairment and irregular professional dental care were associated with higher rates of untreated tooth decay. There were no significant associations with medical conditions or the number of medications taken. Nursing home residents have high levels of untreated coronal and root caries, particularly those with high needs due to functional impairment but poor access to professional services. © 2014 Australian Dental Association.

  9. Factors causing risks of caries evolvement in dental solid tissues under acclimatization

    Directory of Open Access Journals (Sweden)

    R.S. Rakhmanov

    2017-12-01

    Full Text Available We analyzed parameters characterizing mineral balance in a body and dental state in two groups of healthy men (n = 15 in each, aged 34.7 ± 0.6 in hot and humid marine climate conditions; one group was made of people undergoing acclimatization, the second one consisted of local population. We assessed working conditions and their category, and metrological data with determining environmental thermal load (ETL-index. Both groups worked outdoors; their labor had IIb category; they had to work overtime and under increased psy-choemotional loads; their working conditions differed as per nutrition and accommodation. When people from both groups had to work beyond their permanent location, their nutrition was represented by individual rations. Labor hardness was assessed as 3.2; labor intensity, as 3.2. Daytime temperature reached 30,0 С, relative air humidity was 77.3 ± 2.6 %, wind speed was 4.3 ± 0.3 m/sec. Microclimate was assessed as having 3.1 hazard category. Overall, working conditions were assessed as hazardous (3.3 hazard category. Electrolyte balance in a body was violated and it was proved by ower contents of K, Na, and Cl in blood serum; it was more apparent in people who were undergoing acclimatization. 70.0 % of local people had Ca contents in blood serum lower than the physiological standard. Lower Ca and increased P contents in blood serum were also detected in those undergoing acclimatization which could be evidence that Ca was washed out of a body and greater risk of dental caries occurred. As per observation dynamics we detected the following processes in people undergoing acclimatization: pH saliva and its mineralizing function shifting to acidity, salivation rate, and lower enamel resistance; they proved there was a growth in dental solid tissues demineralization. These parameters corresponded to those detected in local population. It calls for primary prevention activities aimed at fighting caries of dental solid tissues.

  10. Effects of gamma radiation on hard dental tissues of albino rats using scanning electron microscope - Part 1

    Science.gov (United States)

    El-Faramawy, Nabil; Ameen, Reham; El-Haddad, Khaled; Maghraby, Ahmed; El-Zainy, Medhat

    2011-12-01

    In the present study, 40 adult male albino rats were used to study the effect of gamma radiation on the hard dental tissues (enamel surface, dentinal tubules and the cementum surface). The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy gamma doses. The effects of irradiated hard dental tissues samples were investigated using a scanning electron microscope. For doses up to 0.5 Gy, there was no evidence of the existence of cracks on the enamel surface. With 1 Gy irradiation dose, cracks were clearly observed with localized erosive areas. At 2 Gy irradiation dose, the enamel showed morphological alterations as disturbed prismatic and interprismatic areas. An increase in dentinal tubules diameter and a contemporary inter-tubular dentine volume decrease were observed with higher irradiation dose. Concerning cementum, low doses,<0.5 Gy, showed surface irregularities and with increase in the irradiation dose to≥1 Gy, noticeable surface irregularities and erosive areas with decrease in Sharpey's fiber sites were observed. These observations could shed light on the hazardous effects of irradiation fields to the functioning of the human teeth.

  11. Child friendly colors in a pediatric dental practice.

    Science.gov (United States)

    Umamaheshwari, N; Asokan, Sharath; Kumaran, Thanga S

    2013-01-01

    The child's perception of the dental environment is a significant factor causing dental anxiety. If the color of the dental environment can have a positive impact on the child's behavior, it is possible that those colors may add to the comfort of a child, thus reducing dental anxiety. To evaluate the association between color and emotions of children in a pediatric dental set-up. A total of 300 children aged 6-12 years were divided into 2 groups: Younger children (6-9 years, n = 156) and older children (9-12 years, n = 144). All the children were asked to shade two cartoon faces representing happiness and fear with their most preferred color. For the positive emotion, 44% (n = 132) of the children preferred yellow, followed by blue 32.67% (n = 98). For negative emotion, 56.67% (n = 170) of the children preferred black and 42.67% (n = 128) preferred red. Association between color and emotion was highly significant (P color research to dental anxiety in children visiting a dental clinic. The use of child friendly colors like yellow and blue in the dental work place could enhance a positive dental attitude in the child's mind.

  12. Recovery of crystallographic texture in remineralized dental enamel.

    Directory of Open Access Journals (Sweden)

    Samera Siddiqui

    Full Text Available Dental caries is the most prevalent disease encountered by people of all ages around the world. Chemical changes occurring in the oral environment during the caries process alter the crystallography and microstructure of dental enamel resulting in loss of mechanical function. Little is known about the crystallographic effects of demineralization and remineralization. The motivation for this study was to develop understanding of the caries process at the crystallographic level in order to contribute towards a long term solution. In this study synchrotron X-ray diffraction combined with scanning electron microscopy and scanning microradiography have been used to correlate enamel crystallography, microstructure and mineral concentration respectively in enamel affected by natural caries and following artificial demineralization and remineralization regimes. In particular, the extent of destruction and re-formation of this complex structure has been measured. 2D diffraction patterns collected at the European Synchrotron Radiation Facility were used to quantify changes in the preferred orientation (crystallographic texture and position of the (002 Bragg reflection within selected regions of interest in each tooth slice, and then correlated with the microstructure and local mineral mass. The results revealed that caries and artificial demineralization cause a large reduction in crystallographic texture which is coupled with the loss of mineral mass. Remineralization restores the texture to the original level seen in healthy enamel and restores mineral density. The results also showed that remineralization promotes ordered formation of new crystallites and growth of pre-existing crystallites which match the preferred orientation of healthy enamel. Combining microstructural and crystallographic characterization aids the understanding of caries and erosion processes and assists in the progress towards developing therapeutic treatments to allow affected

  13. Acid Rather Than Nonacid Reflux Burden Is a Predictor of Tooth Erosion.

    Science.gov (United States)

    Ganesh, Meenakshi; Hertzberg, Anne; Nurko, Samuel; Needleman, Howard; Rosen, Rachel

    2016-02-01

    The relation between tooth erosion (TE) and gastroesophageal reflux in children has not been clearly established, and there are no studies to determine the relation with refluxate height, nonacid reflux, and erosions. The aim of this study was to determine the relation between TE and acid and nonacid gastroesophageal refluxes measured using combined pH and multichannel intraluminal impedance (pH-MII). We conducted a prospective cohort study of children presenting for pH-MII testing. Once informed consent was obtained, patients completed questionnaires about their reflux symptoms and diet, and then underwent pH-MII catheter placement and a dental examination. The Keels-Coffield erosion index was used to score the extent and severity of TE. Reflux parameters of patients with and without TE were compared using Student t test and correlations were performed using Spearman correlations. A total of 27 patients participated in the study, all of whom were on acid suppression at the time of pH-MII testing. Of the 27 patients, 10 (37%) had TE. There were significant positive correlations between acid reflux episodes (r = 0.44, P = 0.02), the percentage of time that acid reflux was present in the distal esophagus (r = 0.44, P = 0.02), and reflux index (r = 0.54, P = 0.004) with the number of TE in a given patient. The percentage of time that acid reflux was present in the proximal esophagus was positively correlated with the number of teeth erosions per patient with borderline significance (r = 0.38, P = 0.05). There was a positive correlation between acid reflux parameters and TE. Acid, rather than nonacid reflux, seems to have a significant role in the pathogenesis of TE.

  14. Tracheobronchial Foreign Body Aspiration: Dental Prosthesis

    Directory of Open Access Journals (Sweden)

    Ataman Köse

    2014-01-01

    Full Text Available It is important to extract foreign bodies for avoiding life-threatening complications. They can lead to death if they are not treated. Different signs and symptoms could occur according to the complete or partial airway obstruction. Foreign body aspiration is a rare incident in adults. The organic foreign materials such as foods are found to be aspirated more commonly and are usually settled in the right bronchial system. However, dental prosthesis and teeth aspirations are rare in literature. In our study, a 52-year-old male patient who had aspirated the front part of his lower dental prosthesis accidentally is presented and the foreign body is extracted by using rigid bronchoscopy. There are many causes of aspiration but dental prosthetic aspirations should be kept in mind during sleep. For this reason, dental apparatus must be taken out while asleep.

  15. Hunter-gatherer dental pathology: Do historic accounts of Aboriginal Australians correspond to the archeological record of dental disease?

    Science.gov (United States)

    Littleton, Judith

    2018-03-01

    Studies of hunter-gatherer oral pathology, particularly in Australia, often focus upon dental wear and caries or assume that historic studies of Aboriginal people reflect the precontact past. Consequently the range of population variation has been underestimated. In this paper dental pathology from human remains from Roonka are compared with a model of dental pathology derived from historic studies. The aim is to identify aspects of dental pathology indicative of regional or intra-population diversity. Adult dentitions (n = 115) dating from the mid to late Holocene were recorded for the following conditions: dental wear, caries, periapical voids, calculus, periodontal disease and antemortem tooth loss. Statistical analysis was used to identify patterns of dental pathology and to identify causal relationships between conditions. Dental wear is marked while dental caries rates are extremely low. Other indications of dental pathology are uncommon (<7% of teeth affected). Temporal heterogeneity is apparent: there are 3 young adults with caries who died in the postcontact period. There is also a small group of middle age to old adults with disproportionate abscessing and pulp exposure who may represent temporal variation or heterogeneity in individual frailty. The results confirm dental wear as the major cause of dental pathology in this group and that, at a general level, historic accounts do correspond with this archeological sample. However, intra-sample heterogeneity is apparent while 2 dental conditions, calculus and periodontal disease, along with the pattern of sex differences deviate from expectation, demonstrating that to identify regional variation attention needs to be paid to the dentoalveolar complex as a whole. © 2017 Wiley Periodicals, Inc.

  16. Assessing storm erosion hazards

    NARCIS (Netherlands)

    Ranasinghe, Ranasinghe W M R J B; Callaghan, D.; Ciavola, Paolo; Coco, Giovanni

    2017-01-01

    The storm erosion hazard on coasts is usually expressed as an erosion volume and/or associated episodic coastline retreat. The accurate assessment of present-day and future storm erosion volumes is a key task for coastal zone managers, planners and engineers. There are four main approaches that can

  17. Energy dispersive X-ray spectrometry study of the protective effects of fluoride varnish and gel on enamel erosion.

    Science.gov (United States)

    De Carvalho Filho, Antonio Carlos Belfort; Sanches, Roberto Pizarro; Martin, Airton Abrahão; Do Espírito Santo, Ana Maria; Soares, Luís Eduardo Silva

    2011-09-01

    Dental erosion is a risk factor for dental health, introduced by today's lifestyle. Topical fluoride applications in the form of varnishes and gel may lead to deposition of fluoride on enamel. This in vitro study aimed to evaluate the effect of two fluoride varnishes and one fluoride gel on the dissolution of bovine enamel by acids. Enamel samples (72) were divided (n = 8): artificial saliva (control-G1), Pepsi Twist® (G2), orange juice (G3), Duraphat® + Pepsi Twist® (G4), Duraphat® + orange juice (G5), Duofluorid® + Pepsi Twist® (G6), Duofluorid® + orange juice (G7), fluoride gel + Pepsi Twist® (G8), and fluoride gel + orange juice (G9). Fluoride gel was applied for 4 min and the varnishes were applied and removed after 6 h. The samples were submitted to six cycles (demineralization: Pepsi Twist® or orange juice, 10 min; remineralization: saliva, 1 h). Samples were analyzed by energy-dispersive X-ray fluorescence (144 line-scanning). The amount of Ca and P decreased significantly in the samples of G2 and G3, and the Ca/P ratio decreased in G3. Mineral gain (Ca) was greater in G9 samples than in G4 > G3 > G5 > G1, and (P) greater in G7 samples than in G9 > G4-6 > G2-3. The protective effect of Duofluorid® was significantly lower than fluoride gel against orange juice. The fluoride varnishes can interfere positively with the dissolution of dental enamel in the presence of acidic beverages. Fluoride gel showed the best protection level to extrinsic erosion with low costs. Copyright © 2010 Wiley-Liss, Inc.

  18. Measurement of erosion: Is it possible?

    NARCIS (Netherlands)

    Stroosnijder, L.

    2005-01-01

    Reasons for erosion measurements are: (1) to determine the environmental impact of erosion and conservation practices, (2) scientific erosion research; (3) development and evaluation of erosion control technology; (4) development of erosion prediction technology and (5) allocation of conservation

  19. Mapping Soil Erosion Factors and Potential Erosion Risk for the National Park "Central Balkan"

    Science.gov (United States)

    Ilieva, Diliana; Malinov, Ilia

    2014-05-01

    Soil erosion is widely recognised environmental problem. The report aims at presenting the main results from assessment and mapping of the factors of sheet water erosion and the potential erosion risk on the territory of National Park "Central Balkan". For this purpose, the Universal Soil Loss Equation (USLE) was used for predicting soil loss from erosion. The influence of topography (LS-factor) and soil erodibility (K-factor) was assessed using small-scale topographic and soil maps. Rainfall erosivity (R-factor) was calculated from data of rainfalls with amounts exceeding 9.5 mm from 14 hydro-meteorological stations. The values of the erosion factors (R, K and LS) were presented for the areas of forest, sub-alpine and alpine zones. Using the methods of GIS, maps were plotted presenting the area distribution among the classes of the soil erosion factors and the potential risk in the respective zones. The results can be used for making accurate decisions for soil conservation and sustainable land management in the park.

  20. TILLAGE EROSION: THE PRINCIPLES, CONTROLLING FACTORS AND MAIN IMPLICATIONS FOR FUTURE RESEARCH

    Directory of Open Access Journals (Sweden)

    Agnieszka Wysocka-Czubaszek

    2014-10-01

    Full Text Available Tillage erosion is one of the major contributors to landscape evolution in hummocky agricultural landscapes. This paper summarizes the available data describing tillage erosion caused by hand-held or other simple tillage implements as well as tools used in typical conventional agriculture in Europe and North America. Variations in equipment, tillage speed, depth and direction result in a wide range of soil translocation rates observed all over the world. The variety of tracers both physical and chemical gives a challenge to introduce the reliable model predicting tillage erosion, considering the number and type of tillage operation in the whole tillage sequence.

  1. Utilization of radiometric method in evaluation of wear on human dental enamel in vitro by dental porcelain glazed and polished; Utilizacao do metodo radiometrico na avaliacao in vitro do desgaste provocado ao esmalte dental humano por porcelanas dentais glazeadas e polidas

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Lena Katekawa; Campos, Tomie Nakakuki de; Adachi, Eduardo Makoto [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Protese]. E-mail: katekawa@usp.br; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: mitiko@curiango.ipen.br

    2005-07-01

    The dental porcelain is a material commonly used in prosthesis. Disadvantages of dental porcelain use include possibility to cause tooth or dental materials wear. Before its use in the mouth, surfaces are treated with polishing and/or glazing. This research used the radiometric method to verify the influence of these surface treatments on the porcelains of commercial brands: Ceramco II, Noritake and Finesse. This method was originally developed for dentifrice abrasiveness evaluation. Five specimens of dental enamel and 10 specimens of each porcelain (5 glazed, 5 polished) were used. The dental enamel was flattened and irradiated with neutrons from the IEA-R1 (IPEN/CNEN) nuclear reactor. Then it was weared by each porcelain in sliding motion, with water. After 2,500 cycles for each porcelain specimen, the released enamel residue was measured. The enamel wear was evaluated by measuring beta activity of {sup 32}P transferred to water from the irradiated tooth. Results varied from 2.57 to 5.81 {mu}g of enamel /mm{sup 2} weared surface. There was no statistical difference ({alpha}=0.05) between dental enamel wear caused by the same porcelains glazed or polished. The results suggest that adequate surface finishing depend on the type of dental porcelain. (author)

  2. Monitoring marginal erosion in hydroelectric reservoirs with terrestrial mobile laser scanner

    Directory of Open Access Journals (Sweden)

    A. M. G. Tommaselli

    2014-06-01

    Full Text Available Marginal erosions in reservoirs of hydroelectric plants have caused economic and environmental problems concerning hydroelectric power generation, reduction of productive areas and devaluing land parcels. The real extension and dynamics of these erosion processes are not well known for Brazilian reservoirs. To objectively assess these problems Unesp (Univ Estadual Paulista and Duke Energy are developing a joint project which aims at the monitoring the progression of some erosive processes and understanding the causes and the dynamics of this phenomenon. Mobile LASER scanning was considered the most suitable alternative for the challenges established in the project requirements. A MDL DynaScan Mobile LASER M150 scanner was selected which uses RTK for real time positioning integrated to an IMU, enabling instantaneous generation of georeferenced point clouds. Two different reservoirs were choose for monitoring: Chavantes (storage plant and Rosana (run-of-river plant, both in the Paranapanema River, border of São Paulo and Paraná States, Brazil. The monitoring areas are scanned quarterly and analysed with base on the point cloud, meshes, contours and cross sections. Cross sections are used to visualize and compute the rate and the dynamics of erosion. Some examples and quantitative results are presented along with an analysis of the proposed technique. Some recommendations to improve the field work and latter data processing are also introduced.

  3. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Kocasarac, Husniye Demirturk [Dept. of Comprehensive Dentistry, The University of Texas Health Science Center, San Antonio (United States); Celenk, Peruze [Dept. of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ondokuz Mayis University, Samsun (Turkmenistan)

    2017-06-15

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images.

  4. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    International Nuclear Information System (INIS)

    Kocasarac, Husniye Demirturk; Celenk, Peruze

    2017-01-01

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images

  5. Auto consolidated cohesive sediments erosion; Erosion des sediments cohesifs en autoconsolidation

    Energy Technology Data Exchange (ETDEWEB)

    Ternat, F

    2007-02-15

    Pollutants and suspended matters of a river can accumulate into the sedimentary column. Once deposited, they are submitted to self-weight consolidation processes, ageing and burying, leading to an increase of their erosion resistance. Pollutant fluxes can be related to sedimentary fluxes, determined by threshold laws. In this work, an erosion threshold model is suggested by introducing a cohesion force into the usual force balance. A model of cohesion is developed on the basis of interactions between argillaceous cohesive particles (clays), particularly the Van der Waals force, whose parameterization is ensured by means of granulometry and porosity. Artificial erosion experiments were performed in a recirculating erosion flume with natural cored sediments where critical shear stress measurements were performed. Other analyses provided granulometry and porosity. The results obtained constitute a good database for the literature. The model is then applied to the experimental conditions and gives good agreement with measurements. An example of the accounting for self-weight consolidation processes is finally suggested, before finishing on a Mohr like diagram dedicated to soft cohesive sediment erosion. (author)

  6. Summary of: Mind the gap! A comparison of oral health knowledge between dental, healthcare professionals and the public.

    Science.gov (United States)

    Levine, R S

    2014-02-01

    The importance of consistent, accurate and unambiguous messages are well documented in oral health promotion literature. Whether the reality of delivering messages in the field fulfils these principle is questionable. This paper explores the perceptions of dental professionals, healthcare professionals and lay community members with regard to key oral health messages in order to highlight any inconsistencies and knowledge gaps between and within groups for disease risk factors. A questionnaire was administered to individuals who belonged to three groups: dental professionals, healthcare professionals and lay community members. The questionnaire established knowledge regarding risk factors for caries, periodontal disease and erosion. Thirty-five (57.4%) of the dental group answered the whole questionnaire correctly, with 22 (27.8%) and 9 (5.1%) of the healthcare and lay community group answering the whole questionnaire correctly, respectively. The question of fluoride levels in children's toothpaste was the main reason for incorrect answers in the dental group. The results of this survey demonstrate a knowledge gradient from dental professionals through to healthcare professionals and then to lay members of the community. The knowledge base observed in the dental group is reflected in the other two groups as would be expected albeit with a significant gap between each group. As expected the dental professionals are generally well informed, but not as well informed as could be expected.

  7. High-Z material erosion and its control in DIII-D carbon divertor

    Directory of Open Access Journals (Sweden)

    R. Ding

    2017-08-01

    Full Text Available As High-Z materials will likely be used as plasma-facing components (PFCs in future fusion devices, the erosion of high-Z materials is a key issue for high-power, long pulse operation. High-Z material erosion and redeposition have been studied using tungsten and molybdenum coated samples exposed in well-diagnosed DIII-D divertor plasma discharges. By coupling dedicated experiments and modelling using the 3D Monte Carlo code ERO, the roles of sheath potential and background carbon impurities in determining high-Z material erosion are identified. Different methods suggested by modelling have been investigated to control high-Z material erosion in DIII-D experiments. The erosion of Mo and W is found to be strongly suppressed by local injection of methane and deuterium gases. The 13C deposition resulting from local 13CH4 injection also provides information on radial transport due to E ×B drifts and cross field diffusion. Finally, D2 gas puffing is found to cause local plasma perturbation, suppressing W erosion because of the lower effective sputtering yield of W at lower plasma temperature and for higher carbon concentration in the mixed surface layer.

  8. Effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin

    Directory of Open Access Journals (Sweden)

    Flávia Emi Razera BALDASSO

    2017-05-01

    Full Text Available Abstract This study aimed to evaluate the effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin. Sixty root canals from mandibular incisors were instrumented and randomly divided into six groups (n = 10 according to the irrigant used: QMiX, 17% EDTA, 10% citric acid (CA, 1% peracetic acid (PA, 2.5% NaOCl (solution control, and distilled water (negative control. The chelating solutions were used to irrigate the canal followed by 2.5% NaOCl as a final flush. After the irrigation protocols, all specimens were rinsed with 10 mL of distilled water to remove any residue of the chemical solutions. Before and after the final irrigation protocols, dentin microhardness was measured with a Knoop indenter. Three indentations were made at 100 µm and 500 µm from the root canal lumen. Afterwards, the specimens were prepared for scanning electron microscopic analysis and the amount of dentin erosion was examined. Wilcoxon and Kruskal-Wallis tests were used to analyze the results with a significance level set at 5%. At 100 µm, all protocols significantly reduced dentin microhardness (p < .05, while at 500 µm, this effect was detected only in the EDTA and QMiX groups (p < .05. CA was the irrigant that caused more extensive erosion in dentinal tubules, followed by PA and EDTA. QMiX opened dentinal tubules, but did not cause dentin erosion. Results suggest that QMiX and 17% EDTA reduced dentin microhardness at a greater depth. Additionally, QMiX did not cause dentin erosion.

  9. Climate change impact on soil erosion in the Mandakini River Basin, North India

    Science.gov (United States)

    Khare, Deepak; Mondal, Arun; Kundu, Sananda; Mishra, Prabhash Kumar

    2017-09-01

    Correct estimation of soil loss at catchment level helps the land and water resources planners to identify priority areas for soil conservation measures. Soil erosion is one of the major hazards affected by the climate change, particularly the increasing intensity of rainfall resulted in increasing erosion, apart from other factors like landuse change. Changes in climate have an adverse effect with increasing rainfall. It has caused increasing concern for modeling the future rainfall and projecting future soil erosion. In the present study, future rainfall has been generated with the downscaling of GCM (Global Circulation Model) data of Mandakini river basin, a hilly catchment in the state of Uttarakhand, India, to obtain future impact on soil erosion within the basin. The USLE is an erosion prediction model designed to predict the long-term average annual soil loss from specific field slopes in specified landuse and management systems (i.e., crops, rangeland, and recreational areas) using remote sensing and GIS technologies. Future soil erosion has shown increasing trend due to increasing rainfall which has been generated from the statistical-based downscaling method.

  10. Rainfall erosivity in Europe.

    Science.gov (United States)

    Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale; Meusburger, Katrin; Klik, Andreas; Rousseva, Svetla; Tadić, Melita Perčec; Michaelides, Silas; Hrabalíková, Michaela; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Beguería, Santiago; Alewell, Christine

    2015-04-01

    Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the R-factor in the USLE model and its revised version, RUSLE. At national and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based on the best available datasets. Data have been collected from 1541 precipitation stations in all European Union (EU) Member States and Switzerland, with temporal resolutions of 5 to 60 min. The R-factor values calculated from precipitation data of different temporal resolutions were normalised to R-factor values with temporal resolutions of 30 min using linear regression functions. Precipitation time series ranged from a minimum of 5 years to a maximum of 40 years. The average time series per precipitation station is around 17.1 years, the most datasets including the first decade of the 21st century. Gaussian Process Regression (GPR) has been used to interpolate the R-factor station values to a European rainfall erosivity map at 1 km resolution. The covariates used for the R-factor interpolation were climatic data (total precipitation, seasonal precipitation, precipitation of driest/wettest months, average temperature), elevation and latitude/longitude. The mean R-factor for the EU plus Switzerland is 722 MJ mm ha(-1) h(-1) yr(-1), with the highest values (>1000 MJ mm ha(-1) h(-1) yr(-1)) in the Mediterranean and alpine regions and the lowest (<500 MJ mm ha(-1) h(-1) yr(-1)) in the Nordic countries. The erosivity density (erosivity normalised to annual precipitation amounts) was also the highest in Mediterranean regions which implies high risk for erosive events and floods

  11. Reconstruction-based Digital Dental Occlusion of the Partially Edentulous Dentition

    Science.gov (United States)

    Zhang, Jian; Xia, James J.; Li, Jianfu; Zhou, Xiaobo

    2016-01-01

    Partially edentulous dentition presents a challenging problem for the surgical planning of digital dental occlusion in the field of craniomaxillofacial surgery because of the incorrect maxillomandibular distance caused by missing teeth. We propose an innovative approach called Dental Reconstruction with Symmetrical Teeth (DRST) to achieve accurate dental occlusion for the partially edentulous cases. In this DRST approach, the rigid transformation between two symmetrical teeth existing on the left and right dental model is estimated through probabilistic point registration by matching the two shapes. With the estimated transformation, the partially edentulous space can be virtually filled with the teeth in its symmetrical position. Dental alignment is performed by digital dental occlusion reestablishment algorithm with the reconstructed complete dental model. Satisfactory reconstruction and occlusion results are demonstrated with the synthetic and real partially edentulous models. PMID:26584502

  12. Enhancing rates of erosion and uplift through glacial perturbations

    Science.gov (United States)

    Norton, Kevin; Schlunegger, Fritz; Abbühl, Luca

    2010-05-01

    Research over the past decade has shown that the pattern of modern rock uplift in the Swiss Alps correlates with both long-term (thermochronometers) and short-term (cosmogenic nuclide-derived denudation rates, sediment loads, lake fills) measures of erosion. This correlation has been attributed alternately to isostatic causes (compensation to erosion and/or glacial unloading) and tectonic forces (ongoing collision and partial delamination). Of these potential driving forces, only isostatic compensation to erosion fits all available structural, geodetic, and flexural models. We explore this uplift-erosion relationship by analyzing river channel steepness for Alpine rivers. Zones of oversteepening, and hence enhanced stream power, are associated with glacial erosion and deposition during LGM and earlier glaciations, resulting in the focusing of erosion into the inner gorges which connect hanging tributary valleys to the main glacial trunk valley. These inner gorges are transient zones in which fluvial and hillslope processes are in the process of re-adjusting this glacially perturbed landscape. Bedrock properties also play a major role in the response time of these adjustments. Glacially generated knickzones are located within 5 km of the trunk stream in the Rhone valley where resistant lithologies dominate (gneiss), whereas the knickzones have migrated as much as 10 km or further in the less resistant rocks (buendnerschists) of the Rhine valley. We suggest that the rock uplift pattern is controlled by surface denudation as set by the glacial-interglacial history of the Alps. Rapid, focused erosion results in rapid rock uplift rates in the Central Swiss Alps, where glaciers were most active. An interesting ramification of this reasoning is that in the absence of glacial perturbation, both rock uplift rates and denudation rates would be substantially lower in this isostatically compensated mountain belt.

  13. Dental anomalies in children submitted to antineoplastic therapy.

    Science.gov (United States)

    Carrillo, Camila Merida; Corrêa, Fernanda Nahás Pires; Lopes, Nilza Nelly Fontana; Fava, Marcelo; Odone Filho, Vicente

    2014-06-01

    Cancer is the third most frequent cause of death in children in Brazil. Early diagnosis and medical advances have significantly improved treatment outcomes, which has resulted in higher survival rates and the management of late side effects has become increasingly important in caring for these patients. Dental abnormalities are commonly observed as late effects of antineoplastic therapy in the oral cavity. The incidence and severity of the dental abnormalities depend on the child's age at diagnosis and the type of chemotherapeutic agent used, as well as the irradiation dose and area. The treatment duration and aggressivity should also be considered. Disturbances in dental development are characterized by changes in shape, number and root development. Enamel anomalies, such as discoloration, opacities and hypoplasia are also observed in these patients. When severe, these abnormalities can cause functional and esthetic sequelae that have an impact on the children's and adolescents' quality of life. General dentists and pediatric dentists should understand these dental abnormalities and how to identify them aiming for early diagnosis and appropriate treatment.

  14. Dental anomalies in children submitted to antineoplastic therapy

    Directory of Open Access Journals (Sweden)

    Camila Merida Carrillo

    2014-06-01

    Full Text Available Cancer is the third most frequent cause of death in children in Brazil. Early diagnosis and medical advances have significantly improved treatment outcomes, which has resulted in higher survival rates and the management of late side effects has become increasingly important in caring for these patients. Dental abnormalities are commonly observed as late effects of antineoplastic therapy in the oral cavity. The incidence and severity of the dental abnormalities depend on the child's age at diagnosis and the type of chemotherapeutic agent used, as well as the irradiation dose and area. The treatment duration and aggressivity should also be considered. Disturbances in dental development are characterized by changes in shape, number and root development. Enamel anomalies, such as discoloration, opacities and hypoplasia are also observed in these patients. When severe, these abnormalities can cause functional and esthetic sequelae that have an impact on the children's and adolescents' quality of life. General dentists and pediatric dentists should understand these dental abnormalities and how to identify them aiming for early diagnosis and appropriate treatment.

  15. Immunohistochemical Study of p53 Expression in Patients with Erosive and Non-Erosive Oral Lichen Planus

    Science.gov (United States)

    Shiva, Atena; Zamanian, Ali; Arab, Shahin; Boloki, Mahsa

    2018-01-01

    Statement of the Problem: Oral lichen planus is a common mucocutaneous lesion with a chronic inflammatory process mediated by immune factors while a few cases of the disease become malignant. Purpose: This study aimed to determine the frequency of p53 marker as a tumor suppressor in patients with erosive and non-erosive oral lichen planus (OLP) by using immunohistochemical methods. Materials and Method: This descriptive cross-sectional study investigated the p53 expression in 16 erosive OLP, 16 non-erosive OLP samples, and 8 samples of normal oral mucosa through immunohistochemistry. The percentage of stained cells in basal and suprabasal layers, and inflammatory infiltrate were graded according to the degree of staining; if 0%, 50% of the cells were stained, they were considered as (-), (+), (++), (+++) and (++++), respectively. The obtained data was statistically analyzed and compared by using Chi square and Fisher’s exact test. Results: The mean percentage of p53 positive cells in erosive OLP (34.5±14.2) was considerably higher than that in non-erosive OLP (23.8±10.4) and normal mucosa (17.5±17). There was a significant difference among the three groups of erosive, non-erosive and control in terms of staining intensity. No significant difference existed between the patients’ age and sex in the two OLP groups. Conclusion: The increased incidence of p53 from normal mucosa to erosive OLP indicated the difference between biological behavior of erosive and non-erosive OLP. It can be claimed that the erosive OLP has great premalignant potential compared with the non-erosive one.

  16. Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

    Directory of Open Access Journals (Sweden)

    Adrian Lussi

    Full Text Available This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA to pH 5.5, calcium (Ca, inorganic phosphate (Pi, and fluoride (F concentration, and degree of saturation ((pK -pIHAP, (pK -pIFAP, and (pK-pICaF2 of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers and surface reflection intensity (SRI at baseline (SH baseline and SRI baseline, after a total of 2 min (SH2 min and after 4 min (SH4 min and SRI4 min erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm. There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007, but no differences between the two types of teeth were observed after two challenges (SH4 min. After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

  17. Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

    Science.gov (United States)

    Lussi, Adrian; Carvalho, Thiago Saads

    2015-01-01

    This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments) on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA) to pH 5.5, calcium (Ca), inorganic phosphate (Pi), and fluoride (F) concentration, and degree of saturation ((pK -pI)HAP, (pK -pI)FAP, and (pK-pI)CaF2) of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers) and surface reflection intensity (SRI) at baseline (SH baseline and SRI baseline), after a total of 2 min (SH2 min) and after 4 min (SH4 min and SRI4 min) erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm). There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN) than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007), but no differences between the two types of teeth were observed after two challenges (SH4 min). After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

  18. Coastal erosion: Coast problem of the Colombian Caribbean; Erosion costera: Problema de la costa del Caribe Colombiano

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Jaime Orlando

    1986-11-01

    The erosion promoted by the sea, affects different sectors of the coast of the Colombian Caribbean. The erosion is particularly clear in the central and western sector of the coast. The coastal problem of Punta Sabanilla - Puerto Salgar - Puerto Colombia; Pueblo Nuevo - Lomarena; Manzanillo del Mar; La Boquilla; sector Tolu - Covenas and Arboletes areas are described. This discussion is presented comform to the data obtained in field and of the revision of maps, pictures and other documents related with the coast design. The coastal erosion is not only affecting to low areas conformed by beaches, but rather this phenomenon impacts on rocky cliffs of different elevation; it is the case of El Castillo and Punta Sabanilla to Barranquilla (west Part) sectors . The causes of the setback that it experiences the coast of the Colombian Caribbean are not known in clear form; however they can be contributing such factors as: the elevation of the sea level, phenomenon that has been checked in different costs of the world; equally it can be due to a decrease in the volume of silts contributed by the Magdalena River, inside the coastal area. A third factor would be related with the diapirism of mud, that possibly would be altering the conformation of the Caribbean littoral.

  19. Sensibilidad postratamiento de blanquamiento dental con la solución de McInnes en pacientes con fluorosis dental grado TF4

    OpenAIRE

    Paredes Balseca, Jenny Carolina

    2017-01-01

    The dental sensibility is one of the problems caused by multiple factors, one of them is the posttreatment sensibility to the dental clearance, nevertheless it is the most used method at present in the persons who has dental fluorosis with the purpose of improving the color of the tooth and the esthetics, in the present investigation there was studied the behavior of the application of solution of McInnes in this type of teeth by relation to the sensibility Objective: To evaluate the degree o...

  20. Noise Levels in Dental Offices and Laboratories in Hamedan, Iran

    Directory of Open Access Journals (Sweden)

    F. Mojarad

    2009-12-01

    Full Text Available Objective: Noise pollution is one of the most important situations requiring a solution by the contemporary world. The National Institute for Occupational Safety and Health has identified noise as one of the ten leading causes of work-related diseases and injuries.Dentists and dental auxiliaries are exposed to different noise levels while working in dental offices or laboratories. The purpose of this study was to measure the noise level made by different dental instruments in dental offices and laboratories.Materials and Methods: Measurement of the noise level was performed in 89 dental offices and nine dental laboratories. The noise levels were determined using a sound level meter; type SL-4011(Lutron ,which was placed at the operator’s ear level in dental offices and laboratories and also at two-meter distance from the technician’s ear in laboratories.Results: The maximum sound level was 85.8 dB in dental offices and 92.0 dB in laboratories.In dental clinics, the highest noise was produced by the ultrasonic-scaler (85.8 dB and the lowest noise (49.7 dB by the high-volume aspirator, whereas in the laboratory,the highest noise was caused during grinding by the stonecutter (92.0 dB and the lowest by the denture-polishing unit (41.0 dB.Conclusion: After close evaluation, we believe that the maximum noise level in dental offices, although often beneath the damaging noise level for the human ear, is very close to the limit of hearing loss (85.0 dB. However, laboratory technicians may be at risk ifthey choose not to wear ear protection (earplugs or earmuffs.

  1. Erosion of tungsten armor after multiple intense transient events in ITER

    International Nuclear Information System (INIS)

    Bazylev, B.N.; Janeschitz, G.; Landman, I.S.; Pestchanyi, S.E.

    2005-01-01

    Macroscopic erosion by melt motion is the dominating damage mechanism for tungsten armour under high-heat loads with energy deposition W > 1 MJ/m 2 and τ > 0.1 ms. For ITER divertor armour the results of a fluid dynamics simulation of the melt motion erosion after repetitive stochastically varying plasma heat loads of consecutive disruptions interspaced by ELMs are presented. The heat loads for particular single transient events are numerically simulated using the two-dimensional MHD code FOREV-2D. The whole melt motion is calculated by the fluid dynamics code MEMOS-1.5D. In addition for the ITER dome melt motion erosion of tungsten armour caused by the lateral radiation impact from the plasma shield at the disruption and ELM heat loads is estimated

  2. Erosion of tungsten armor after multiple intense transient events in ITER

    Science.gov (United States)

    Bazylev, B. N.; Janeschitz, G.; Landman, I. S.; Pestchanyi, S. E.

    2005-03-01

    Macroscopic erosion by melt motion is the dominating damage mechanism for tungsten armour under high-heat loads with energy deposition W > 1 MJ/m 2 and τ > 0.1 ms. For ITER divertor armour the results of a fluid dynamics simulation of the melt motion erosion after repetitive stochastically varying plasma heat loads of consecutive disruptions interspaced by ELMs are presented. The heat loads for particular single transient events are numerically simulated using the two-dimensional MHD code FOREV-2D. The whole melt motion is calculated by the fluid dynamics code MEMOS-1.5D. In addition for the ITER dome melt motion erosion of tungsten armour caused by the lateral radiation impact from the plasma shield at the disruption and ELM heat loads is estimated.

  3. Effect of a Person-Centered Course on the Empathic Ability of Dental Students.

    Science.gov (United States)

    Rosenzweig, Julien; Blaizot, Alessandra; Cougot, Nancie; Pegon-Machat, Estelle; Hamel, Olivier; Apelian, Nareg; Bedos, Christophe; Munoz-Sastre, Maria-Teresa; Vergnes, Jean-Noel

    2016-11-01

    Person-centered or patient-centered care (PCC) focuses on the individual's needs and concerns. Although PCC is widely acknowledged as a core value of modern medicine, there has been a lack of research on how dental curricula could engage future dentists in PCC approaches. The aim of this study was to assess the impact of a PCC course on empathy in dental students. A controlled study was conducted with fourth-year dental students in four dental faculties in France in 2014-15. The test group (n=63) received 20 hours of PCC training including arts-based approaches, narrative dentistry activities, and workshops on communication based on the Calgary-Cambridge guide. There was no change in the curriculum of the control group (n=217). Pretest and posttest measures with the Toronto Empathy Questionnaire (TEQ) and Jefferson Scale of Physician Empathy (JSPE) were compared for the two groups. The comparisons showed no significant differences on the TEQ or JSPE (p=0.25 and p=0.08, respectively). However, there was a higher proportion of students with more than an eight-point decrease in TEQ values in the control group (p=0.02). The stabilization of empathic ability in the test group may have counteracted the tendency for natural erosion of empathy among students during their clinical activities. These results suggest that PCC training constitutes a promising approach to developing dental students' empathic ability, but there is a need to assess the effects of such training over longer periods.

  4. Prevalence of traumadc dental Injuries among new orthodondc ...

    African Journals Online (AJOL)

    The prevalence of dental trauma was significantly higher in males (p<0.05) and most frequently observed In patients aged 6 to 10 years. Falls was the commonest cause of dental traumatic Injuries among the patients (37.5%). The most common type of trauma to the teeth was enamel fracture (46. 9%) followed by avulslon ...

  5. Implementing new code requirements for erosion-corrosion

    International Nuclear Information System (INIS)

    Deardorff, A.F.

    1992-01-01

    In late 1986, severe erosion-corrosion wall thinning led to complete severance of a condensate line at the Surry nuclear plant in the United States. This prompted the acceleration of a number of industry programmes to understand the cause of the faster-than-expected wall thinning, and to provide guidelines for identification, inspection and evaluation of potentially affected piping systems. (author)

  6. Impacts of shoreline erosion on coastal ecosystems in Songkhla Province

    Directory of Open Access Journals (Sweden)

    Nipaporn Chusrinuan

    2009-07-01

    Full Text Available Songkhla Province is located on the eastern coast of the southern Thai Peninsula, bordering the Gulf of Thailand for approximately 107 km. Most of the basin’s foreshores have been extensively developed for housing, tourism and shrimp farming. The beaches are under deteriorating impacts, often causing sediment transport which leads to an unnaturally high erosion rate. This natural phenomenon is considered to be a critical problem in the coastal areas affected by the hazard of coastal infrastructure and reduced beach esthetics for recreation. In this study, shoreline changes were compared between 1975 and 2006 using aerial photographs and Landsat imageries using Geographic Information System (GIS. The results revealed that 18.5 km2 of the coastal areas were altered during the period. Of this, 17.3 km2 suffered erosion and 1.2 km2were subjected to accretion. The most significant changes occurred between 1975-2006. Shoreline erosion was found at Ban Paktrae, Ranot District, with an average erosion rate of 5.3 m/year, while accretion occurred at Laem Samila, MuangSongkhla District with an average accretion rate of 2.04 m/year. The occurrences of shoreline erosion have contributed to the degradation of coastal soil and water quality, destruction of beach and mangrove forests, loss of human settlements and livelihood.These processes have led to deterioration of the quality of life of the residents. Prevention and mitigation measures to lessen economic and social impacts due to shoreline erosion are discussed.

  7. Rainfall erosivity map for Ghana

    International Nuclear Information System (INIS)

    Oduro Afriyie, K.

    1995-10-01

    Monthly rainfall data, spanning over a period of more than thirty years, were used to compute rainfall erosivity indices for various stations in Ghana, using the Fournier index, c, defined as p 2 /P, where p is the rainfall amount in the wettest month and P is the annual rainfall amount. Values of the rainfall erosivity indices ranged from 24.5 mm at Sunyani in the mid-portion of Ghana to 180.9 mm at Axim in the south western coastal portion. The indices were used to construct a rainfall erosivity map for the country. The map revealed that Ghana may be broadly divided into five major erosion risk zones. The middle sector of Ghana is generally in the low erosion risk zone; the northern sector is in the moderate to severe erosion risk zone, while the coastal sector is in the severe to extreme severe erosion risk zone. (author). 11 refs, 1 fig., 1 tab

  8. Dental practitioners and ill health retirement: a qualitative investigation into the causes and effects.

    Science.gov (United States)

    Hill, K B; Burke, F J T; Brown, J; Macdonald, E B; Morris, A J; White, D A; Murray, K

    2010-09-11

    Data published in 1999 from the Government Actuary on the National Health Service Pension Scheme (1989-1994) have indicated that the frequency of ill health premature retirement (IHR) was four times more prevalent among dentists at age 42 years compared with doctors.Objective The aim of this project was to determine the factors that contributed to IHR in dental practitioners, and the effects of IHR on their lives. Semi-structured interviews were carried out during 2007. A topic list was developed, piloted and used to guide the interviewer. A purposive sampling technique was used to recruit the respondents from an insurance company database. A framework approach to data analysis was utilised. Twenty-three respondents were interviewed, 19 male and 4 female, aged between 39-59 years. Depression, stress and anxiety were reported by respondents to be major causes of their retirement, followed by musculoskeletal disease and premature disability caused by trauma. This is illustrated by the following: '...just went straight into general practice but with some regrets. Practice was so depressing' (GDS/NHS); 'I withdraw, I don't engage ... I found it more and more difficult and one morning... I collapsed in tears at the practice' (GDS/NHS). Dentists reported both negative and positive comments in relation to support received from their health insurance company. The main causes of IHR were depression, musculoskeletal disease and specific skin conditions. Respondents expressed concern regarding the level of support available to dentists in distress. Respondents to this study found that continuing to work had a positive impact on their health.

  9. Oral Streptococcal Endocarditis, Oral Hygiene Habits, and Recent Dental Procedures: A Case-Control Study.

    Science.gov (United States)

    Duval, Xavier; Millot, Sarah; Chirouze, Catherine; Selton-Suty, Christine; Moby, Vanessa; Tattevin, Pierre; Strady, Christophe; Euvrard, Edouard; Agrinier, Nelly; Thomas, Daniel; Hoen, Bruno; Alla, François

    2017-06-15

    We aimed to compare oral hygiene habits, orodental status, and dental procedures in patients with infective endocarditis (IE) according to whether the IE-causing microorganism originated in the oral cavity. We conducted an assessor-blinded case-control study in 6 French tertiary-care hospitals. Oral hygiene habits were recorded using a self-administered questionnaire. Orodental status was analyzed by trained dental practitioners blinded to the microorganism, using standardized clinical examination and dental panoramic tomography. History of dental procedures was obtained through patient and dentist interviews. Microorganisms were categorized as oral streptococci or nonoral pathogens using an expert-validated list kept confidential during the course of the study. Cases and controls had definite IE caused either by oral streptococci or nonoral pathogens, respectively. Participants were enrolled between May 2008 and January 2013. Cases (n = 73) were more likely than controls (n = 192) to be aged calculus, and infectious dental diseases did not significantly differ between groups. Patients with IE caused by oral streptococci differ from patients with IE caused by nonoral pathogens regarding background characteristics, oral hygiene habits, and recent dental procedures, but not current orodental status. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com

  10. 75 FR 33169 - Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation...

    Science.gov (United States)

    2010-06-11

    .... FDA-2008-N-0163] (formerly Docket No. 2001N-0067) RIN 0910-AG21 Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation of Special Controls for Dental Amalgam... the Federal Register of August 4, 2009 (74 FR 38686) which classified dental amalgam as a class II...

  11. Extent of Cropland and Related Soil Erosion Risk in Rwanda

    Directory of Open Access Journals (Sweden)

    Fidele Karamage

    2016-06-01

    Full Text Available Land conversion to cropland is one of the major causes of severe soil erosion in Africa. This study assesses the current cropland extent and the related soil erosion risk in Rwanda, a country that experienced the most rapid population growth and cropland expansion in Africa over the last decade. The land cover land use (LCLU map of Rwanda in 2015 was developed using Landsat-8 imagery. Based on the obtained LCLU map and the spatial datasets of precipitation, soil properties and elevation, the soil erosion rate of Rwanda was assessed at 30-m spatial resolution, using the Revised Universal Soil Loss Equation (RUSLE model. According to the results, the mean soil erosion rate was 250 t·ha−1·a−1 over the entire country, with a total soil loss rate of approximately 595 million tons per year. The mean soil erosion rate over cropland, which occupied 56% of the national land area, was estimated at 421 t·ha−1·a−1 and was responsible for about 95% of the national soil loss. About 24% of the croplands in Rwanda had a soil erosion rate larger than 300 t·ha−1·a−1, indicating their unsuitability for cultivation. With a mean soil erosion rate of 1642 t·ha−1·a−1, these unsuitable croplands were responsible for 90% of the national soil loss. Most of the unsuitable croplands are distributed in the Congo Nile Ridge, Volcanic Range mountain areas in the west and the Buberuka highlands in the north, regions characterized by steep slopes (>30% and strong rainfall. Soil conservation practices, such as the terracing cultivation method, are paramount to preserve the soil. According to our assessment, terracing alone could reduce the mean cropland soil erosion rate and the national soil loss by 79% and 75%, respectively. After terracing, only a small proportion of 7.6% of the current croplands would still be exposed to extreme soil erosion with a rate >300 t·ha−1·a−1. These irremediable cropland areas should be returned to mountain forest to

  12. Quantifying accelerated soil erosion through ecological site-based assessments of wind and water erosion

    Science.gov (United States)

    This work explores how organising soil erosion assessments using established groupings of similar soils (ecological sites) can inform systems for managing accelerated soil erosion. We evaluated aeolian sediment transport and fluvial erosion rates for five ecological sites in southern New Mexico, USA...

  13. Rill erosion rates in burned forests

    Science.gov (United States)

    Joseph W. Wagenbrenner; Peter R. Robichaud

    2011-01-01

    Introduction Wildfires often produce large increases in runoff and erosion rates (e.g., Moody and Martin, 2009), and land managers need to predict the frequency and magnitude of postfire erosion to determine the needs for hazard response and possible erosion mitigation to reduce the impacts of increased erosion on public safety and valued resources. The Water Erosion...

  14. Evaluation of the serum zinc level in erosive and non-erosive oral lichen planus.

    Science.gov (United States)

    Gholizadeh, N; Mehdipour, M; Najafi, Sh; Bahramian, A; Garjani, Sh; Khoeini Poorfar, H

    2014-06-01

    Lichen planus is a chronic inflammatory immunologic-based disease involving skin and mucosa. This disease is generally divided into two categories: erosive and non-erosive. Many etiologic factors are deliberated regarding the disease; however, the disorders of immune system and the role of cytotoxic T-lymphocytes and monocytes are more highlighted. Zinc is an imperative element for the growth of epithelium and its deficiency induces the cytotoxic activity of T-helper2 cells, which seems to be associated with lichen planus. This study was aimed to evaluate the levels of serum zinc in erosive and non-erosive oral lichen planus (OLP) and to compare it with the healthy control group to find out any feasible inference. A total of 22 patients with erosive oral lichen planus, 22 patients with non erosive OLP and 44 healthy individuals as the control group were recruited in this descriptive-comparative study. All the participants were selected from the referees to the department of oral medicine, school of dentistry, Tabriz University of Medical Sciences. Serum zinc level was examined for all the individuals with liquid-stat kit (Beckman Instruments Inc.; Carlsbad, CA). Data were analyzed by adopting the ANOVA and Tukey tests, using SPSS 16 statistical software. The mean age of patients with erosive and non-erosive LP was 41.7 and 41.3 years, respectively. The mean age of the healthy control group was 34.4 years .The mean serum zinc levels in the erosive and non erosive lichen planus groups and control groups were 8.3 (1.15), 11.15 (0.92) and 15.74 (1.75) μg/dl respectively. The difference was statistically significant (poral lichen planus. This finding may probably indicate the promising role of zinc in development of oral lichen planus.

  15. A history of wind erosion prediction models in the United States Department of Agriculture Prior to the Wind Erosion Prediction System

    Science.gov (United States)

    The Great Plains experienced an influx of settlers in the late 1850s to 1900. Periodic drought was hard on both settlers and the soil and caused severe wind erosion. The period known as the Dirty Thirties, 1931 to 1939, produced many severe windstorms, and the resulting dusty sky over Washington, D....

  16. Modeling soil erosion in a watershed

    OpenAIRE

    Lanuza, R.

    1999-01-01

    Most erosion models have been developed based on a plot scale and have limited application to a watershed due to the differences in aerial scale. In order to address this limitation, a GIS-assisted methodology for modeling soil erosion was developed using PCRaster to predict the rate of soil erosion at watershed level; identify the location of erosion prone areas; and analyze the impact of landuse changes on soil erosion. The general methodology of desktop modeling or soil erosion at watershe...

  17. Monitoring and Risk Identification Caused by High Water, Floods and Erosion Processes in Urban Part of Sava Riverbed

    Science.gov (United States)

    Oskoruš, D.; Miković, N.; Ljevar, I.

    2012-04-01

    Riverbed erosion and bottom deepening are part of natural fluvial processes in the upper stream of Sava River. The increasing gradient of those changes is interconnected with the level of human influence in the river basin and riverbed as well. In time period of last forty years the consequences of riverbed erosion are become serious as well as dangerous and they threaten the stability of hydro technical structures. The increasing value of flow velocity in riverbed in urban part of river section during high water level, mud and debris flow during the floods as well, is especially dangerous for old bridges. This paper contains result of velocity measurements during high waters taken by Hydrological Service of Republic Croatia, load transport monitoring during such events and cross sections in some vulnerable location. In this paper is given one example of Jakuševac railway bridge in Zagreb, heavily destroyed during high water event on the 30 March 2009., recently reconstructed by "Croatian Railways" company. Keywords: Riverbed erosion, flow velocity, mud and debris flow, risk identification, stability of bridges

  18. Dental Amalgam

    Science.gov (United States)

    ... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

  19. Difficult factors in Management of Impacted Dental Prosthesis in Esophagus

    Directory of Open Access Journals (Sweden)

    Efiaty A. Soepardi

    2005-03-01

    Full Text Available A dental prosthesis which ingested and impacted in esophagus, is an emergency case and life threatening, so require immediate esophagoscopy intervention for removing. The objective of this study is to assess some factors can caused dtfficulties in diagnosing and treating the ingested and impacted dental prosthesis in the esophagus and their complications. This retrospective study analyzed patient’s chart whose underwent esophagoscopy for removing the impacted dental prosthesis in Dr. Cipto Mangunkusumo General Hospital, Jakarta, Indonesia during a period between January 1997 and December 2003. Neck-chest X-ray and esophagoscopy were performed in all patients to identify the existence of the dental prosthesis as a diagnostic and treatment procedure. The length of time for removing the dental prosthesis was recorded and stated as a less difficult esophagoscopy when it takes time less than 60 minutes and as a difficult  esophagoscopy takes 60 minutes or longer. Some risk difficulties factors were statistically analyzed. There were 53 patients of ingested dental prosthesis in esophagus. Only 51 cases were analyzed According to the length of time for removing the dental prosthesis by esophagoscopy, 22 patients were recorded as less difficult cases and 29 patients as difficult cases. Two cases among the cases needed cervicotomy after unsuccessful esophagoscopy removal. The difficulties to diagnose an impacted dental prosthesis in the esophagus caused by unreliable clinical history, unclear signs and symptoms, unable to be detected by X-ray and was not found during esophagoscopy. The difficulties in treating due to mucosal laceration, edema, bleeding, failure of the first extraction and conformity with the size and shape, the wire outside the dental prosthesis and the length of time stayed in the esophagus. (Med J Indones 2005; 14: 33-6Keywords: ingested dental prosthesis, radioluscent foreign body, length of time of esophagoscopy

  20. A comparative study of pH modulation and trace elements of various fruit juices on enamel erosion: An in vitro study

    Directory of Open Access Journals (Sweden)

    S.V.S.G Nirmala

    2011-01-01

    Full Text Available Fruit juices are popular worldwide with children of all ages as they are sweet and perceived to be healthful. This in vitro study was sought to measure pH of 10 different fruit juices, to find out possible erosive effects on human dental enamel of 40 extracted sound premolars and also to measure fluoride and trace elements of these juices. The estimation of pH of fruit juices was done by using Systronic upH 362 pH meter. The erosive effects of fruit juices were tested by using polarized light microscope. Orion electrode was used to measure fluoride. The trace elements were estimated by using Atomic Absorption Spectrophotometer No. 6501F. The pH values in different juices were observed at different levels, and pH values of these juices were more acidic than baseline after 24 hours. As the time increased, the erosion effect became more in pineapple; grape and sugarcane juices, and they had more cariogenic trace elements like selenium, iron and manganese. So, these juices were found to be cariogenic. To conclude, orange, mousambi, mango, pomegranate, apple, chikku and watermelon juices had no erosive effect on the human enamel, with the presence of highest amount of trace elements like fluoride and phosphorous which are considered as strongly cariostatic.