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Sample records for early permanent dentition

  1. Evaluation of Craniofacial Morphology of Children with Dental Fluorosis in Early Permanent Dentition Period

    OpenAIRE

    Dogan, Alev Aksoy; Bolpaca, Pinar

    2009-01-01

    Objectives High intake of fluoride (>1.5 mg/L) for a prolonged period may lead to skeletal fluorosis as well as dental fluorosis. The aim of this study was to compare the craniofacial characteristics of children with dental fluorosis in early permanent dentition period to those without fluorosis. Methods Two hundred and sixteen children in early permanent dentition (girls:121, boys:95) were included in the study. Study group was composed of 124 children with dental fluorosis who was born and ...

  2. A possible association between early apical resorption of primary teeth and ectodermal characteristics of the permanent dentition

    DEFF Research Database (Denmark)

    Bille, M L B; Kvetny, M J; Kjaer, I

    2008-01-01

    The hypothesis of this study is that children with unexpected early apical resorption of the primary teeth are also predisposed to resorption in the permanent dentition. Accordingly, the aim was to perform a longitudinal study focussing on the permanent teeth in children with unexpected early api...... dentition: In all 12 children, dental deviations in the permanent dentition were observed. Additionally, idiopathic external apical resorption of the permanent teeth was seen in three children, two of whom had received orthodontic treatment....

  3. Malnutrition-related early childhood exposures and enamel defects in the permanent dentition: A longitudinal study from the Bolivian Amazon.

    Science.gov (United States)

    Masterson, Erin E; Fitzpatrick, Annette L; Enquobahrie, Daniel A; Mancl, Lloyd A; Conde, Esther; Hujoel, Philippe P

    2017-07-28

    We investigated the relationship between early childhood malnutrition-related measures and subsequent enamel defects in the permanent dentition. This cohort study included 349 Amerindian adolescents (10-17 years, 52% male) from the Bolivian Amazon. Exposures included: stunted growth (height-for-age z-scores), underweight (weight-for-age z-scores), anemia (hemoglobin), acute inflammation (C-reactive protein) and parasitic infection (hookworm). We measured the occurrence (no/yes) and extent (2/3) of enamel defects. We estimated associations between childhood exposures and enamel defect measures using log-binomial and multinomial logistic regression. The prevalence of an enamel defect characterized by an orange peel texture on a large central depression on the labial surface of the central maxillary incisors was 92.3%. During childhood (1-4 years), participants had a high prevalence of stunted growth (75.2%), anemia (56.9%), acute inflammation (39.1%), and hookworm infection (49.6%). We observed associations between childhood height-for-age (OR = 0.65; P = 0.028 for >2/3 extent vs. no EH) and gastrointestinal hookworm infection (OR = 3.43; P = 0.035 for >2/3 extent vs. no defects or <1/3 extent) with enamel defects. The study describes a possibly novel form of enamel hypoplasia and provides evidence for associations of malnutrition-related measures in early childhood, including stunted growth and parasitic helminth infection, with the observed enamel defects. © 2017 Wiley Periodicals, Inc.

  4. Morphometrics of Permanent Dentition in Chennai Population

    Directory of Open Access Journals (Sweden)

    K Sridhar

    2011-01-01

    The study is helpful in establishling Bolton′s standards for assessing tooth size discrepancy and also in application of mixed dentition model analysis and bracket positioning chart for preadjusted edgewise appliance for the local population.

  5. Supernumerary Teeth in Primary Dentition and Early Intervention: A Series of Case Reports

    Science.gov (United States)

    Bahadure, Rakesh N.; Thosar, Nilima; Jain, Eesha S.; Kharabe, Vidhi; Gaikwad, Rahul

    2012-01-01

    Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition. Mesiodens is the most common type of supernumerary teeth but rarely seen in lower arch. Early recognition and diagnosis of supernumerary teeth is important to prevent further complications in permanent dentition. Four cases of supernumerary teeth with mesiodens in upper and lower arch in primary dentition and their management have been discussed. PMID:22888456

  6. Supernumerary Teeth in Primary Dentition and Early Intervention: A Series of Case Reports

    Directory of Open Access Journals (Sweden)

    Rakesh N. Bahadure

    2012-01-01

    Full Text Available Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition. Mesiodens is the most common type of supernumerary teeth but rarely seen in lower arch. Early recognition and diagnosis of supernumerary teeth is important to prevent further complications in permanent dentition. Four cases of supernumerary teeth with mesiodens in upper and lower arch in primary dentition and their management have been discussed.

  7. Supernumerary teeth in primary dentition and early intervention: a series of case reports.

    Science.gov (United States)

    Bahadure, Rakesh N; Thosar, Nilima; Jain, Eesha S; Kharabe, Vidhi; Gaikwad, Rahul

    2012-01-01

    Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition. Mesiodens is the most common type of supernumerary teeth but rarely seen in lower arch. Early recognition and diagnosis of supernumerary teeth is important to prevent further complications in permanent dentition. Four cases of supernumerary teeth with mesiodens in upper and lower arch in primary dentition and their management have been discussed.

  8. [Angle class I malocclusion in primary dentition and findings in permanent dentition--a follow-up study].

    Science.gov (United States)

    Legovic, M; Legovic, A; Skrinjaric, T; Sasso, A; Mady, B

    2005-01-01

    The aim of the study was to examine stability and changes in Angle Class I malocclusion from deciduous to permanent dentition in 168 subjects. All the subjects had Class I malocclusion in deciduous dentition, and were examined by the same orthodontist on two occasions during deciduous and permanent dentition. None of the subjects had received orthodontic therapy in the meantime. The results showed considerable changes from primary to permanent dentition. Crowding in primary dentition was retained in permanent dentition in 45.2% cases. In 16.2% cases it changed into normocclusion and 38.6% subjects developed other types of malocclusion. Open bite was retained in permanent dentition in 17.8% cases and in 17.8% subjects transformed into normocclusion. 64.4% subjects developed other types of malocclusion. Cross bite was retained in permanent dentition in 21.4% cases and in 28.6% subjects changed to normocclusion. Other types of malocclusion in permanent dentition developed in 50% subjects. In 30.8% of cases finding of premature loss of deciduous teeth was accompanied by extraction of some permanent teeth. Normocclusion was retained in 19.2% cases while 50% of children developed some type of malocclusion. Crowding, which was retained in permanent dentition in 45.2% cases, showed the highest degree of stability. Children with this type of anomaly in primary dentition displayed the highest frequency of total malocclusions (83.3% subjects). Out of all anomalies in primary dentition, cross bite most frequently switched to normal occlusion in permanent dentition (in 28.6% cases).

  9. Serial extraction or premolar extraction in the permanent dentition? Comparison of duration and outcome of orthodontic treatment.

    Science.gov (United States)

    Wagner, M; Berg, R

    2000-01-01

    Treatment outcome and duration of 2 different treatment approaches in 2 groups of comparable extraction cases were analyzed: Group I: serial extraction performed in the early mixed dentition followed by orthodontic treatment in the permanent dentition; group II: extractions as well as orthodontic treatment in the permanent dentition. The following conclusions were reached: 1. The treatment period with fixed appliances was highly significantly shorter in group I; however, the number of appointments was significantly higher and the total duration of treatment/observation time significantly longer. 2. In both groups the reduction in PAR score was either improved or greatly improved in all cases.

  10. Is tooth wear in the primary dentition predictive of tooth wear in the permanent dentition? Report from a longitudinal study.

    LENUS (Irish Health Repository)

    Harding, M A

    2010-03-01

    To determine the prevalence of tooth wear in the permanent dentition of a sample of 12-year-old school children and establish whether an association exists between tooth wear recorded now and tooth wear recorded in their primary dentition at age five.

  11. Is Malnutrition Associated with Crowding in Permanent Dentition?

    Directory of Open Access Journals (Sweden)

    Erika B. A. F. Thomaz

    2010-09-01

    Full Text Available Evidence suggests that energy-protein malnutrition is associated with impaired growth and development of facial bones. The objective of this study was to investigate the association between nutritional status and reduced space for dental eruption (crowding in permanent dentition. A cross-sectional study with probabilistic sampling design was used. We evaluated 2,060 students aged 12 to 15 years enrolled in schools in the northeast of Brazil. Crowding was defined according to World Health Organization (WHO as misalignment of teeth due to lack of space for them to erupt in the correct position. Nutritional status was evaluated by means of body mass index and height-for-age, using the WHO’s reference curves. Parents and adolescents responded to a questionnaire about demographic, socioeconomic, biological and behavioral characteristics. The associations were estimated by odds ratio (OR in multivariate logistic regression analysis (alpha = 0.05. Confounding and effect-modification were taken into account. An association between low height-for-age (z-score < –1SD and crowding was only observed in adolescents with a prolonged history of mouth breathing (OR = 3.1. No association was observed between underweight and crowding. Malnutrition is related to crowding in permanent dentition among mouth-breathing adolescents. Policy actions aimed at reducing low height-for-age and unhealthy oral habits are strongly recommended. However, further studies are needed to increase the consistency of these findings and improve understanding of the subject.

  12. Influence of host-related risk indicators on dental caries in permanent dentition.

    Science.gov (United States)

    Delgado-Angulo, Elsa K; Bernabé, Eduardo

    2006-01-01

    The aim of this study was to assess the individual and grouped influence of host-related factors on dental caries experience in permanent dentition of 7-9 year-old children. One hundred and twenty one children were recruited applying a stratified cluster sampling without replacement. Clinical examinations, Colorimetric Test and non-stimulated and stimulated saliva collection were performed; the samples obtained were later incubated using Snyder culture medium. Simple and multiple binary logistic regression analyses were performed to assess the individual and grouped influence of the host-related factors and establish a modelfor predicting dental caries in permanent dentition. 78.5% of the evaluated children presented dental caries in permanent dentition. Binary logistic regression analyses revealMd that only dental caries in deciduous dentition and stimulated salivary flow were significantly associated to dental caries in permanent dentition. The final multivariate model showed that the adjusted OR was 1.76 for an increase of 1 tooth in dmft and 2.29 for a decrease of 1 ml in stimulated salivary flow. Dental caries in deciduous dentition is a risk indicator for dental caries in permanent dentition, and stimulated salivary flow is a protective factor Variables like enamel resistance to acid dissolution and buffer capacity are not related to dental caries in permanent dentition, making them inappropriate for risk studies.

  13. Supragingival Microbial Profiles of Permanent and Deciduous Teeth in Children with Mixed Dentition

    National Research Council Canada - National Science Library

    Shi, Weihua; Qin, Man; Chen, Feng; Xia, Bin

    2016-01-01

    The present study was designed to investigate the microbial profiles of teeth in different locations in mixed-dentition-stage children, and to compare the microbiomes of permanent and deciduous teeth...

  14. Breastfeeding, bottle feeding and risk of malocclusion in mixed and permanent dentitions: a systematic review.

    Science.gov (United States)

    Abreu, Lucas Guimarães; Paiva, Saul Martins; Pordeus, Isabela Almeida; Martins, Carolina Castro

    2016-01-01

    The aim of the present study was to search for scientific evidence concerning the association between breastfeeding and bottle feeding and risk of malocclusion in mixed and permanent dentitions. An electronic search was performed in eight databases up to February 2015. Additionally, a gray literature search and hand searches of the reference lists of the selected studies were also carried out. There were no restrictions on language or on year of publication. The methodology of the included articles was evaluated using the Newcastle Ottawa scale. Out of the 817 identified citations, six studies fulfilled the eligibility criteria and were included in the systematic review. One study showed that children with mixed and permanent dentitions breastfed for more than 6 months presented greater mean protrusion of mandibular incisors and inclination of maxillary incisors compared with those breastfed for less than 6 months or those who were bottle-fed (p bottle feeding and the occurrence of malocclusion in mixed and permanent dentitions.

  15. Longitudinal occlusal changes from primary to permanent dentition in children with normal primary occlusion.

    Science.gov (United States)

    Legovic, M; Mady, L

    1999-06-01

    This purpose of this research was to examine the stability of normal occlusion during the transition from primary to permanent dentition. The sample consisted of 128 children (83 boys and 45 girls) 4.5 to 5.5 years old with normal occlusion in the primary dentition. The subjects were reexamined at 12.5 to 13.5 years. None had received orthodontic treatment. Although all the subjects had normal occlusion in the primary dentition, 72.7% (73.5% boys and 71.1% girls) had developed anomalies following eruption of the permanent teeth. These anomalies included crowding, Class II Division 1 or Class II Division 2 malocclusion, mesial occlusion complex, lateral crossbite, anterior crossbite, premature tooth loss, openbite or other anomalies.

  16. Mesiodistal root angulation of permanent teeth in children with mixed dentition and normal occlusion

    Directory of Open Access Journals (Sweden)

    Flávia A. S. Jesuino

    2010-12-01

    Full Text Available OBJECTIVE: There is little information regarding the mesiodistal angulation of permanent teeth in mixed dentition. The aim of this study was to evaluate mesiodistal root angulation of permanent incisors, canines and first molars of 100 Brazilian children, using a new horizontal reference plane based on the midpoint of the intercuspation of primary canines and permanent first molars in panoramic radiographs during the mixed-dentition phase. MATERIAL AND METHODS: Children were equally divided between the genders with a mean age of 8.9 years (SD=0.76, normal occlusion and no eruptive disturbances. RESULTS: The angulation of the permanent maxillary first molars was close to the vertical, whereas the mandibular molars presented approximately 25 degrees of distal root angulation. The maxillary canines were the most distally angulated teeth, whereas the permanent mandibular canines were vertically positioned. The evaluation of the anterior maxillary area showed vertical position of permanent lateral, and central incisors with a slight distal angulation, whereas the permanent mandibular incisors tended to a mesial radicular convergence. CONCLUSIONS: The proposed reference line could be useful in mixed dentition root angulation evaluation; there was a slight asymmetry in the mesiodistal angulation among homologous teeth, and also a small variation between the male and the female groups, but no difference between 8-and 10-year-old children.

  17. Occlusal characteristics during different emergence stages of the permanent dentition in Tanzanian Bantu and finnish children.

    NARCIS (Netherlands)

    Mugonzibwa, E.A.; Eskeli, R.; Kuijpers-Jagtman, A.M.; Laine-Alava, M.T.; Hof, M.A. van 't

    2004-01-01

    Occlusal characteristics and anomalies were studied among 869 (428 boys, 441 girls) Tanzanian Bantu children aged 3.5-16 years and 706 (319 boys, 387 girls) Finnish children aged 5-11 years during different emergence stages of the permanent dentition. Various occlusal variables were registered

  18. [Caries of permanent dentition in medieval inhabitants of Wrocław].

    Science.gov (United States)

    Staniowski, Tomasz; Dabrowski, Paweł; Gawlikowska-Sroka, Aleksandra

    2011-01-01

    The study of dentition plays an important role in the reconstruction of the diet and in assessment of the overall health and living conditions of paleopopulations. The aim of this study was to determine the condition of permanent dentition of medieval inhabitants of Wrocław basing on the prevalence and intensity of caries in permanent dentition. The material consisted of 1156 permanent teeth from 118 skulls recovered from two medieval cemeteries in Wrocław: the parish cemetery at the St. Elisabeth Church (13th-14th century) and the cemetery in Ołbin (12th-13th century). Two age classes were formed taking into account anthropologic assessment and group size. The younger class consisted of material up to the age of 35 years; the remaining skulls were assigned to the older class. The prevalence and incidence of caries was determined. The prevalence and intensity of caries was 56.91% and 15.7%, respectively. Carious lesions predominated in males and in the older age class. The prevalence and intensity of caries in permanent dentition did not differ from other medieval populations and increased with age. High prevalence of caries reflects a high proportion of carbohydrates in the diet of medieval inhabitants of Wrocław, their high socioeconomic status, and poor oral hygiene.

  19. Mesiodistal crown diameters of permanent dentition in schoolchildren from Lima

    OpenAIRE

    Pineda-Mejia, Martha; Departamento Académico de Estomatología Rehabilitadora, Facultad Odontología de la Universidad Nacional Mayor de San Marco, Perú.; Petkova- Gueorguieva, Marieta; Facultad Odontología de la Universidad Nacional Mayor de San Marcos.

    2015-01-01

    The purpose of this study was to determine the size of mesiodistal diameters of permanent teeth in a school population of the city of Lima, to analyze the differences between homologous teeth, sexual dimorphism of permanent teeth as well as the degree of variability of the measurements. Methodology: The study was conducted on 400 students of mestizos (200 men and 200 women) 10 to 12 years, from three schools in the districts of la Victoria and Barrios Altos, Lima city. The procedure was perfo...

  20. Maxillary canine-first premolar transposition in the permanent dentition: treatment considerations and a case report.

    LENUS (Irish Health Repository)

    Synodinos, Philippos N

    2010-12-01

    Transposition is defined as the interchange of position between two adjacent teeth within the same quadrant of the dental arch. Permanent maxillary canine-premolar transposition is the most commonly observed transposition in the human dentition. Its prevalence is relatively low and its aetiology remains unclear, although it has been associated with genetic factors. It may also be related to a combination of localised factors such as malformation of adjacent teeth, tooth agenesis, retention of the deciduous canine and a history of local trauma. Treatment is selected on an individual case basis after thoroughly considering the overall facial and dental characteristics, duration of treatment, cost, patient preference and the orthodontist\\'s experience. This article provides a case report of maxillary canine transposition in the permanent dentition, successfully managed with orthodontic treatment.

  1. Breastfeeding, bottle feeding and risk of malocclusion in mixed and permanent dentitions: a systematic review

    OpenAIRE

    Abreu, Lucas Guimarães; Paiva,Saul Martins; Pordeus, Isabela Almeida; Martins,Carolina Castro

    2016-01-01

    Abstract The aim of the present study was to search for scientific evidence concerning the association between breastfeeding and bottle feeding and risk of malocclusion in mixed and permanent dentitions. An electronic search was performed in eight databases up to February 2015. Additionally, a gray literature search and hand searches of the reference lists of the selected studies were also carried out. There were no restrictions on language or on year of publication. The methodology of the in...

  2. Prevalence of traumatic injuries to permanent dentition and its association with overjet in a Swiss child population.

    Science.gov (United States)

    Schatz, Jean-Paul; Hakeberg, Magnus; Ostini, Enrico; Kiliaridis, Stavros

    2013-04-01

    Dental trauma is a very common issue in dentistry and its occurrence has been related to many factors. The aim of this study was to evaluate the prevalence of traumatic dental injuries in the permanent dentition among Swiss children and its association with overjet. A sample of 1900 children aged 6-13 years was prospectively evaluated to determine the number and types of injuries, the influence of overjet on the risk of suffering trauma and the relationships between trauma, age, gender and life conditions. The observed prevalence of trauma was higher for boys, with a slight risk increase with age and a peak frequency at the age of 10 years. Most of the injuries (91.2%) involved the upper front teeth; 87.2% of all injuries were hard tissue injuries (enamel or dentin fractures), and 12.8% only subluxation and luxation injuries. Children with an overjet of 6 mm or more had a four times higher risk of suffering trauma, compared with those with less overjet. This cross-sectional study confirmed most of the results from earlier studies dealing with epidemiological factors of dental injuries to the permanent dentition. Of all the variables analysed, overjet stood out as the most significant risk factor: an increased overjet of 6 mm or more had a major impact on the risk of trauma, which would speak in favour of early orthodontic correction of an increased overjet to reduce the prevalence of dental trauma. © 2012 John Wiley & Sons A/S.

  3. Periodontal healing complications following concussion and subluxation injuries in the permanent dentition: a longitudinal cohort study

    DEFF Research Database (Denmark)

    Hermann, Nuno Vibe; Lauridsen, Eva; Ahrensburg, Søren Steno

    2012-01-01

    Purpose The purpose of the study was to analyze the risk of periodontal ligament (PDL) healing complications following concussion and subluxation injuries in the permanent dentition. Material and method A total 469 permanent teeth (358 patients) with concussion and 404 permanent teeth......-related resorption (ankylosis), marginal bone loss, and tooth loss were analyzed with the Kaplan–Meier method. Results Concussion: In teeth with immature root development, no healing complications were observed. For teeth with mature root development, the risk of repair related resorption after 3 years was 3.2% (95...... among teeth with concussion. Subluxation: In teeth with immature root development, the risk of infection-related resorption after 3 years was 1.7% [95% confidence interval (CI): 0–3.8%]. Infection-related resorption occurred significantly more often in teeth with concomitant crown fracture (P = 0...

  4. Extraction the First Permanent Molar With Poor Prognosis in Mixed Dentition Period

    Directory of Open Access Journals (Sweden)

    B Seraj

    2002-02-01

    Full Text Available Whenever the first permanent molar is extracted or its long- term prognosis is poor, before taking any steps, a full clinical and radiographic evaluation associated with patients dental models investigation is necessary to determine the following cases:The quality and quantity of dentition, teeth missing, occlusion, buds position, orthodontic problems, the level of parents and patient cooperation for future long term orthodontic treatment and finally patient's oral hygiene. On the basis of this information, a decision is taken about the first permanent molar extraction with poor prognosis, either of balancing or compensatory type, especially when future orthodontic treatment is improbable. The aim of this article is to explain the principles of time and sequence of first permanent molar extraction.

  5. Premature loss of primary teeth: part I, its overall effect on occlusion and space in the permanent dentition.

    Science.gov (United States)

    Hoffding, J; Kisling, E

    1978-01-01

    Premature loss of primary molars causes, without doubt, permanent changes in regard to space and sagittal molar relations, in the permanent dentition. The changes are due to drifting of teeth and lack of growth, and such changes should, whenever possible, be prevented. In part two of this series of papers, a further analysis of the data will be presented.

  6. Prevalence and distribution of anomalies of permanent dentition in 9584 Japanese high school students.

    Science.gov (United States)

    Hagiwara, Yoshiyuki; Uehara, Tamotsu; Narita, Tatsuya; Tsutsumi, Hirofumi; Nakabayashi, Shinya; Araki, Masao

    2016-09-01

    This study investigated the prevalence and distribution of anomalies of permanent dentition in the current Japanese population by examining an unbiased sample. We conducted a survey of dental anomalies by mass dental screening at eight high schools in 2012. Participants were all students with permanent dentition. Dental anomalies were classified as hypodontia, supernumerary teeth, peg-shaped teeth, fused teeth, and talon cusps. Students with one or more dental anomalies on oral examination were given a differential diagnosis by three specialists. The final sample comprised 9584 participants (5062 boys, 4522 girls). Hypodontia was present in 372 students (3.88 %) with no significant sex difference (191 boys, 181 girls). Frequent sites were the right or left mandibular second premolar, right or left maxillary second premolar, and right or left maxillary lateral incisor. Supernumerary teeth were observed in three boys (0.06 %) and one girl (0.02 %). Peg-shaped teeth were observed in 74 students (0.77 %; 27 boys, 47 girls), differing significantly between sexes; they were most prevalent among maxillary lateral incisors. Of affected students, 18 students (0.19 %) also had hypodontia (3 boys, 15 girls). Fused teeth were present in two boys (0.04 %) and three girls (0.07 %) (gemination in one boy and fusion in the remaining four students). Sites were limited to maxillary and mandibular central and lateral incisors. Talon cusps were observed in two boys (0.04 %) and four girls (0.09 %). The present survey of a large unbiased sample can be considered to reflect the prevalence and distribution of anomalies of permanent dentition in the current Japanese population.

  7. Prevalence and Pattern of Accessory Teeth (Hyperdontia in Permanent Dentition of Iranian Orthodontic Patients.

    Directory of Open Access Journals (Sweden)

    Fariborz Amini

    2013-11-01

    Full Text Available Awareness of hyperdontia pattern/prevalence can be useful in early diagnosis and prevention by general practitioners, pediatric dentists, and orthodontists. Since the previous results regarding the pattern of hyperdontia (supernumerary teeth are controversial, this study aimed to assess this subject among Iranian orthodontic patients.All approved panoramic radiographs of 3374 orthodontic patients (aged 10 to 20 years old who had visited orthodontic departments of all Tehran dentistry universities and 10 private clinics during the years 1999-2009 were investigated to establish the prevalence/pattern of hyperdontia in permanent dentition (excluding third molars. The data were analyzed using a chi-square, a chi-square goodness-of-fit, and a Fisher exact test (α=0.05.Of the patients, 2012 were female and 1362 were male. The prevalence of hyperdontia was 0.72% (14 females [0.69% of females], 10 males [0.73% of males], female-to-male ratio=1:1.055. The difference between the genders was not significant (P = 0.896. No double or multiple supernumeraries were found. The most common accessory teeth were mesiodens (58.3%, maxillary laterals (25%, and maxillary premolars (16.7%. Hyperdontia was significantly more common (P=0.000 in maxilla (there was only one mandibular accessory tooth. It was more frequent in the anterior segment (P=0.000. However the occurrence was not significantly different between bimaxillary right and left quadrants (P=0.6.Hyperdontia was more common in premaxilla, and the most common accessory tooth was mesiodens. Unlike earlier studies, no bilateral accessory teeth were found. Also no gender dimorphism was discerned.

  8. Prevalence and Pattern of Accessory Teeth (Hyperdontia) in Permanent Dentition of Iranian Orthodontic Patients.

    Science.gov (United States)

    Amini, Fariborz; Rakhshan, Vahid; Jamalzadeh, Sanaz

    2013-11-01

    Awareness of hyperdontia pattern/prevalence can be useful in early diagnosis and prevention by general practitioners, pediatric dentists, and orthodontists. Since the previous results regarding the pattern of hyperdontia (supernumerary teeth) are controversial, this study aimed to assess this subject among Iranian orthodontic patients. All approved panoramic radiographs of 3374 orthodontic patients (aged 10 to 20 years old) who had visited orthodontic departments of all Tehran dentistry universities and 10 private clinics during the years 1999-2009 were investigated to establish the prevalence/pattern of hyperdontia in permanent dentition (excluding third molars). The data were analyzed using a chi-square, a chi-square goodness-of-fit, and a Fisher exact test (α=0.05). Of the patients, 2012 were female and 1362 were male. The prevalence of hyperdontia was 0.72% (14 females [0.69% of females], 10 males [0.73% of males], female-to-male ratio=1:1.055). The difference between the genders was not significant (P = 0.896). No double or multiple supernumeraries were found. The most common accessory teeth were mesiodens (58.3%), maxillary laterals (25%), and maxillary premolars (16.7%). Hyperdontia was significantly more common (P=0.000) in maxilla (there was only one mandibular accessory tooth). It was more frequent in the anterior segment (P=0.000). However the occurrence was not significantly different between bimaxillary right and left quadrants (P=0.6). Hyperdontia was more common in premaxilla, and the most common accessory tooth was mesiodens. Unlike earlier studies, no bilateral accessory teeth were found. Also no gender dimorphism was discerned.

  9. Development and evaluation of a standardized method and atlas for contouring primary and permanent dentition

    Science.gov (United States)

    Fang, P; Batra, S; Hollander, A B; Lin, A; Hill-Kayser, C E; Levin, L M; Mupparapu, M

    2015-01-01

    Objectives: Radiation toxicity of the dentition may present significant treatment-related morbidity in the paediatric head and neck cancer population. However, clear dose–effect relationships remain undetermined and must be predicated upon accurate structure delineation and dosimetry at the individual tooth level. Radiation oncologists generally have limited familiarity or experience with relevant dental anatomy. Methods: We therefore developed a detailed CT atlas of permanent and primary dentition. After studying this atlas, five radiation oncology clinicians delineated all teeth for each of eight different cases (selected for breadth of dental maturity and anatomical variability). They were asked to record confidence in their contours on a per-tooth basis as well as the duration of time required per case. Contour accuracy and interclinician variability were assessed by Hausdorff distance and Dice similarity coefficient. All analyses were performed using R v. 3.1.1 and the RadOnc v. 1.0.9 package. Results: Participating clinicians delineated teeth with varying degrees of completeness and accuracy, stratified primarily by the age of the subject. On a per-tooth basis, delineation of permanent dentition was feasible for incisors, canines, premolars and first molars among all subjects, even at the youngest ages. However, delineation of second and third molars was less consistent, commensurate with approximate timing of tooth development. Within each tooth contour, uncertainty was the greatest at the level of the dental roots. Conclusions: Delineation of individual teeth is feasible and serves as a necessary precursor for dental dose assessment and avoidance. Among the paediatric radiation oncology community in particular, this atlas may serve as a useful tool and reference. PMID:25812046

  10. Multiple Pulp Stones in Primary and Developing Permanent Dentition: A Report of 4 Cases

    Directory of Open Access Journals (Sweden)

    Mohita Marwaha

    2012-01-01

    Full Text Available Pulp stones are foci of calcification or discrete calcifications in the dental pulp. They are frequently found on bitewing and periapical radiographs, but their occurrence in entire dentition is unusual. We are reporting four cases in which the occurrence of pulp stones ranged from their presence in just primary teeth (Cases 1 and 2 to involvement of young permanent teeth also (Case 3 and even unerupted permanent teeth (Case 4. In all the cases, dental, medical, and family histories as well as the findings from the clinical examination of the patient were not contributory. Histopathological report revealed true denticle. Metabolic evaluation of patients through liver function test, kidney function test, and blood investigation did not show any metabolic disorders. Patients were also evaluated for any systemic, syndromic, or genetic involvement, but this was also noncontributing. Therefore, it is suggested that these unusual cases may be of idiopathic origin.

  11. Flouride. Ten-year prospective study of deciduous and permanent dentition.

    Science.gov (United States)

    Margolis, F J; Reames, H R; Freshman, E; MaCauley, C D; Mehaffey, H

    1975-07-01

    A ten-year longitudinal prospective study compared the effect of fluoride on dentition of 1,500 children from infancy through age 10 years. In Kalamazoo, Mich, and Oneida, NY, parallel groups were given a fluoride-vitamin supplement from infancy and from age 4 and compared with fluoridated water and control groups. Incidence of new caries activity in both deciduous and permanent teeth was measured by mean number of new decayed and filled teeth, as well as percentage of children with no caries throughout the periods studied. Prevalence of caries was also studied in six-year molars. The results indicate a consistent (and, for selected groups, a statistically significant) diminution in caries activity for both deciduous and permanent teeth for groups ranked from greatest retardation of caries to least: infant fluoride group, water fluoride group, age 4 fluoride group, and controls.

  12. Principles of treatment planning for compromised first permanent molars in mixed dentition period: A review article

    Directory of Open Access Journals (Sweden)

    Behrad Tanbakuchi

    2017-02-01

    Full Text Available Background and Aims: The first permanent molar is susceptible to caries, endodontic complications and developmental anomalies. Compromised teeth with poor prognosis could cause the clinician to face dilemmas. The aim of this review article was to assess recent guidelines on the treatment planning of compromised first permanent molars in mixed dentition period. Materials and Methods: The design of the study was based on review of literature by searching the MEDLINE, Web of science and Google scholar. Key words (permanent first molar, extraction, treatment plan were used. This search was limited to the English articles published after the year 2000. Conclusion: A number of factors influenced decision-making process regarding compromised first permanent molars including the restorative status of the tooth, dental age of the patient, degree of crowding and occlusal relationships were assessed. The ideal time for removal of these teeth was 8-9 years of age. However, the current evidence for managing compromised first permanent molars demands clinical trials.

  13. A case report of bilateral Brodie bite in early mixed dentition using bonded constriction quad-helix appliance.

    Science.gov (United States)

    Nojima, Kunihiko; Takaku, Sakiko; Murase, Chiaki; Nishii, Yasushi; Sueishi, Kenji

    2011-01-01

    Brodie bite is a comparatively rare type of malocclusion found in primary and mixed dentition. It not only adversely affects chewing and muscle functions, but also impairs normal growth and development of the mandible. This report describes the therapeutic results of a patient with bilateral Brodie bite in early mixed dentition after using a bonded constriction quad-helix appliance. The patient, a boy aged 9 years and 2 months, first visited our hospital after occlusal abnormality in the molar region was detected at a local dental clinic. Case analysis resulted in a diagnosis of bilateral Brodie bite with slight mandibular retrognathism. Treatment objectives were to reduce the arch width of the maxillary dentition and expand the mandibular arch in order to establish and stabilize molar occlusion and to achieve a Class I molar relation and appropriate overbite and overjet. Treatment comprised covering the occlusal surface of the maxillary molars with resin and attaching a bonded constriction quad-helix appliance joined with a 0.040-inch quad-helix wire. A bi-helix appliance was also fixed to the mandibular dentition. Brodie bite visibly improved after 5 months. Cervical headgear was then fitted and the patient observed until eruption of the permanent dentition was complete. Class I molar relation was achieved after 2 years and 6 months, although spacing remained in the maxillary and mandibular dentitions. Treatment of bilateral Brodie bite in mixed dentition by means of a bonded constriction quad-helix appliance attached to the maxillary dentition enabled effective bite opening and reduction in the width of maxillary arch independent of the patient's cooperation, providing good therapeutic outcome in a short time period.

  14. Assessment of the size of unerupted permanent canines and premolars in mixed dentition

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    Umićević-Davidović Mirjana

    2012-01-01

    Full Text Available The aim of this study was to find the correlation coefficient between mesiodistal width of permanent lower incisors and permanent canine and premolars for each quadrant, to establish equations for prediction of the sum of canine and premolars based on the sum of the lower incisors for the population of the Republic of Srpska as well as to compare the results with the values provided by Moyers's and Tanaka-Johnston's analysis and detremine sexual dimorphizm in tooth size. We analyzed 100 (50 male and 50 female subjects with permanent dentition and class I molar relationship. The mesiodistal width of the lower permanent incisors, upper and lower canines and premolars were measured using a vernier caliper with the accuracy of 0.1 mm. The results show that for all groups of teeth, there is a significant difference (p <0.001 between mesiodistal width in male and female subjects. A linear regression equations are developed for the upper jaw (female y = 0.5276x +9.9756 and male y = 0.5927 x +8.986 and the lower jaw (female y = 0.489x+10.215 and male y =0.633x +7, 5636. We concluded that values provided by Moyers's and Tanaka-Johston's analysis do not coincide with the values of the population of the Republic of Srpska, but they can be clinically applied, with caution to females.

  15. Temporary management of permanent central incisors loss caused by trauma in primary dentition with natural crowns: a case report.

    Science.gov (United States)

    Tüzüner, Tamer; Kuşgöz, Adem; Nur, Bilge Gülsüm

    2009-10-01

    Primary teeth injuries may cause developmental disturbances in the permanent dentition and loss of permanent incisors could be treated with different options. In this case report, an 11-year-old boy, with a history of trauma at the age of 4 years, is presented. Premature loss of permanent upper right central and upper left central teeth because of the mobility and arrest in root development were treated using patient's own natural crowns on a removable appliance. This treatment option could be considered as an esthetic and functional temporary management of permanent central incisors loss until the definitive treatment will be completed in the future.

  16. Early eruption of permanent canines.

    Science.gov (United States)

    Madhu, S

    2012-01-01

    Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

  17. Early eruption of permanent canines

    Directory of Open Access Journals (Sweden)

    S Madhu

    2012-01-01

    Full Text Available Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

  18. A Longitudinal Study of the Presence of Dental Anomalies in the Primary and Permanent Dentitions of Cleft Lip and/or Palate Patients.

    Science.gov (United States)

    Suzuki, Akira; Nakano, Masayuki; Yoshizaki, Keigo; Yasunaga, Atsushi; Haruyama, Naoto; Takahashi, Ichiro

    2017-05-01

      The aim is to survey primary and permanent dental anomalies: hypodontia, microdontia, a supernumerary tooth, and fused teeth in patients with cleft lip and/or palate.   Retrospective longitudinal study Subjects :  The subjects were selected from all 1724 patients with cleft lip and/or palate who were registered at the orthodontic clinic of Kyushu University Hospital, Fukuoka, Japan, from 1970 to 2009. Finally, 994 subjects were evaluated for primary dentition, 1352 for permanent dentition, and 871 for the longitudinal changes from primary to permanent dentition.   The prevalence of dental anomalies was compared for each tooth type, among various cleft types, between males and females, and between the alveolar cleft area and the noncleft area.   The prevalence of hypodontia was 16.2% for primary dentition and 52.7% for permanent dentition in the subjects with cleft lip and/or palate. Hypodontia increased with the severity of the cleft type. Multiple hypodontia was found more frequently in the subjects with bilateral cleft lip and palate and the subjects with unilateral cleft lip and palate. Microformed lateral incisors were found in 22.7% of permanent lateral incisors but not in primary dentition. Supernumerary teeth were found in 17.7% of the subjects with cleft lip and/or palate for primary maxillary dentition and in 5.7% for permanent maxillary dentition.   The prevalence of hypodontia was greater in permanent dentition than in primary dentition; although, it was not much different between males and females or between the right and left sides. The prevalence of dental anomalies was significantly different among four groups by cleft type: cleft lip, cleft lip and alveolus, cleft lip and palate, and cleft palate.

  19. Bilateral supernumerary teeth in deciduous dentition-a rarity.

    Science.gov (United States)

    Acharya, Sonu; Ghosh, Chiranjit; Mondal, Pradeep Kumar

    2014-05-01

    Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition and more often seen in males. A supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent central incisors which will further alter occlusion and may compromise esthetics and formation of dentigerous cysts. Here we discuss a case of bilateral supernumerary teeth in deciduous dentition in a female child.

  20. Heritable patterns of tooth decay in the permanent dentition: principal components and factor analyses.

    Science.gov (United States)

    Shaffer, John R; Feingold, Eleanor; Wang, Xiaojing; Tcuenco, Karen T; Weeks, Daniel E; DeSensi, Rebecca S; Polk, Deborah E; Wendell, Steve; Weyant, Robert J; Crout, Richard; McNeil, Daniel W; Marazita, Mary L

    2012-03-09

    Dental caries is the result of a complex interplay among environmental, behavioral, and genetic factors, with distinct patterns of decay likely due to specific etiologies. Therefore, global measures of decay, such as the DMFS index, may not be optimal for identifying risk factors that manifest as specific decay patterns, especially if the risk factors such as genetic susceptibility loci have small individual effects. We used two methods to extract patterns of decay from surface-level caries data in order to generate novel phenotypes with which to explore the genetic regulation of caries. The 128 tooth surfaces of the permanent dentition were scored as carious or not by intra-oral examination for 1,068 participants aged 18 to 75 years from 664 biological families. Principal components analysis (PCA) and factor analysis (FA), two methods of identifying underlying patterns without a priori surface classifications, were applied to our data. The three strongest caries patterns identified by PCA recaptured variation represented by DMFS index (correlation, r = 0.97), pit and fissure surface caries (r = 0.95), and smooth surface caries (r = 0.89). However, together, these three patterns explained only 37% of the variability in the data, indicating that a priori caries measures are insufficient for fully quantifying caries variation. In comparison, the first pattern identified by FA was strongly correlated with pit and fissure surface caries (r = 0.81), but other identified patterns, including a second pattern representing caries of the maxillary incisors, were not representative of any previously defined caries indices. Some patterns identified by PCA and FA were heritable (h(2) = 30-65%, p = 0.043-0.006), whereas other patterns were not, indicating both genetic and non-genetic etiologies of individual decay patterns. This study demonstrates the use of decay patterns as novel phenotypes to assist in understanding the multifactorial nature of dental caries.

  1. Heritable patterns of tooth decay in the permanent dentition: principal components and factor analyses

    Directory of Open Access Journals (Sweden)

    Shaffer John R

    2012-03-01

    Full Text Available Abstract Background Dental caries is the result of a complex interplay among environmental, behavioral, and genetic factors, with distinct patterns of decay likely due to specific etiologies. Therefore, global measures of decay, such as the DMFS index, may not be optimal for identifying risk factors that manifest as specific decay patterns, especially if the risk factors such as genetic susceptibility loci have small individual effects. We used two methods to extract patterns of decay from surface-level caries data in order to generate novel phenotypes with which to explore the genetic regulation of caries. Methods The 128 tooth surfaces of the permanent dentition were scored as carious or not by intra-oral examination for 1,068 participants aged 18 to 75 years from 664 biological families. Principal components analysis (PCA and factor analysis (FA, two methods of identifying underlying patterns without a priori surface classifications, were applied to our data. Results The three strongest caries patterns identified by PCA recaptured variation represented by DMFS index (correlation, r = 0.97, pit and fissure surface caries (r = 0.95, and smooth surface caries (r = 0.89. However, together, these three patterns explained only 37% of the variability in the data, indicating that a priori caries measures are insufficient for fully quantifying caries variation. In comparison, the first pattern identified by FA was strongly correlated with pit and fissure surface caries (r = 0.81, but other identified patterns, including a second pattern representing caries of the maxillary incisors, were not representative of any previously defined caries indices. Some patterns identified by PCA and FA were heritable (h2 = 30-65%, p = 0.043-0.006, whereas other patterns were not, indicating both genetic and non-genetic etiologies of individual decay patterns. Conclusions This study demonstrates the use of decay patterns as novel phenotypes to assist in understanding

  2. Management of a multiple dentoalveolar trauma in permanent dentition with avulsion of a canine: a 4-year follow-up.

    Science.gov (United States)

    Senes, Andrea Melo; Sakai, Vivien T; Oliveira, Thais Marchini; Machado, Maria Aparecida A M; Santos, Carlos F; Marzola, Clóvis

    2008-03-01

    Traumatic dental injuries are relatively frequent accidents that typically involve teeth in the maxillary anterior segment. The emergency treatment and the clinical decisions must be efficiently made at the time of injury, and there is a need for long-term follow-up because of the high incidence of complications. The aim of this article was to present the emergency and rehabilitation treatments of a multiple dentoalveolar trauma in the permanent dentition involving different extensions of enamel-dentin crown fracture, pulp exposure, and the avulsion of a canine. The treatment outcomes are reported up to the 4-year follow-up, and the clinical approaches and their rationale are discussed.

  3. Demographic, socioeconomic, and behavioral factors affecting patterns of tooth decay in the permanent dentition: principal components and factor analyses.

    Science.gov (United States)

    Shaffer, John R; Polk, Deborah E; Feingold, Eleanor; Wang, Xiaojing; Cuenco, Karen T; Weeks, Daniel E; DeSensi, Rebecca S; Weyant, Robert J; Crout, Richard; McNeil, Daniel W; Marazita, Mary L

    2013-08-01

    Dental caries of the permanent dentition is a multifactorial disease resulting from the complex interplay of endogenous and environmental risk factors. The disease is not easily quantitated due to the innumerable possible combinations of carious lesions across individual tooth surfaces of the permanent dentition. Global measures of decay, such as the DMFS index (which was developed for surveillance applications), may not be optimal for studying the epidemiology of dental caries because they ignore the distinct patterns of decay across the dentition. We hypothesize that specific risk factors may manifest their effects on specific tooth surfaces leading to patterns of decay that can be identified and studied. In this study, we utilized two statistical methods of extracting patterns of decay from surface-level caries data to create novel phenotypes with which to study the risk factors affecting dental caries. Intra-oral dental examinations were performed on 1068 participants aged 18-75 years to assess dental caries. The 128 tooth surfaces of the permanent dentition were scored as carious or not and used as input for principal components analysis (PCA) and factor analysis (FA), two methods of identifying underlying patterns without a priori knowledge of the patterns. Demographic (age, sex, birth year, race/ethnicity, and educational attainment), anthropometric (height, body mass index, waist circumference), endogenous (saliva flow), and environmental (tooth brushing frequency, home water source, and home water fluoride) risk factors were tested for association with the caries patterns identified by PCA and FA, as well as DMFS, for comparison. The ten strongest patterns (i.e. those that explain the most variation in the data set) extracted by PCA and FA were considered. The three strongest patterns identified by PCA reflected (i) global extent of decay (i.e. comparable to DMFS index), (ii) pit and fissure surface caries and (iii) smooth surface caries, respectively. The

  4. Prevalence of developmental defects of enamel in mixed and permanent dentition of 9 and 12 year old children of Himachal Pradesh, India: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Deepak Chauhan

    2013-01-01

    Full Text Available Objective: The purpose of this study was to determine and compare the prevalence and presentation of developmental defects of the enamel (DDE in the mixed and permanent dentition of healthy school children residing in hills. Materials and Methods: A total of 1188 healthy school children were examined using modified DDE criteria for recording enamel defects. Results: The overall prevalence of DDE of any type was (51.3% in both mixed and permanent dentition. Diffuse opacity was (25.3% the most common defect and demarcated opacity was (23.1% and whereas, enamel hypoplasia was the least prevalent defect with prevalence of (2.9%. Conclusion: The study population showed a high prevalence of DDE in primary as well as in the permanent dentition, reflecting the current increasing trend of this condition, which should be considered as a significant public health problem.

  5. Multiple abnormalities in permanent maxillary incisors following trauma to the primary dentition

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    Nitesh Tewari

    2011-01-01

    Full Text Available Diverse consequences to the trauma to primary dentition are sometimes difficult to explain. This report describes a rare case of sequelae to primary tooth trauma. The traumatic episode which occurred at the age of 3 years resulted in abnormally large crowns of 11 and 21 with yellowish-brown discoloration and enamel hyperplasia. It also led to dilaceration in the root of 21 and enamel hypoplasia with discoloration in 12 and 22.

  6. Analysis of human dentition from Early Bronze Age: 4000-year-old puzzle.

    Science.gov (United States)

    Przystańska, Agnieszka; Lorkiewicz-Muszyńska, Dorota; Abreu-Głowacka, Monica; Glapiński, Mariusz; Sroka, Alicja; Rewekant, Artur; Hyrchała, Anna; Bartecki, Bartłomiej; Żaba, Czesław; Kulczyk, Tomasz

    2017-01-01

    This paper presents the first ever paleodontological investigation of human remains from an archeological site in Central Europe dating from the Early Bronze Age and attributed to the Strzyzow Culture. It corroborates the knowledge gained from archeological, anthropological and genetical investigations. Our study aimed to assess dental status, dental morphology and dental pathologies as well as tooth wear and enamel hypoplasia based on visual inspection and stereomicroscopic investigation. The research was supported by CBCT imaging to obtain digital images and 3D reconstructions as well as 2D radiographs essential for dental age estimation. All of the 191 teeth discovered showed morphological similarity, with adult teeth showing similar color, shape and size. A maxillary molar presenting with a unique root morphology and a mandibular molar with a rare occlusal surface were found. Both permanent and deciduous dentition presented significant tooth wear. A few specimens displayed signs of dental caries, periapical pathology and antemortem tooth loss. Three individuals exhibited linear enamel hypoplasia. CBCT provided high-quality 2D images useful for dental age estimation by non-destructive methods. Estimated dental age correlated with the age estimated by other anthropological methods. In one case, this was crucial because of insufficient material for anthropological analysis. The presented studies have proved that besides the skeleton, teeth can be used as a fundamental tool in assessing the overall health and living conditions of paleopopulations. It would seem that there is potential for considerable development to be made in the research and investigation of paleodontological material using CBCT.

  7. Molariform mesiodens in primary dentition

    National Research Council Canada - National Science Library

    Mangalekar, Sachin B; Ahmed, Tajammul; Zakirulla, M; Shivappa, Halawar Sangmesh; Bheemappa, F B; Yavagal, Chandrashekar

    2013-01-01

    Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch, and incidence of molariform mesiodens in the maxillary midline is rare in permanent dentition and extremely uncommon in primary dentition...

  8. Molariform Mesiodens in Primary Dentition

    National Research Council Canada - National Science Library

    Mangalekar, Sachin B; Ahmed, Tajammul; Zakirulla, M; Shivappa, Halawar Sangmesh; Bheemappa, F. B; Yavagal, Chandrashekar

    2013-01-01

    Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch, and incidence of molariform mesiodens in the maxillary midline is rare in permanent dentition and extremely uncommon in primary dentition...

  9. Interceptive orthopedics for the correction of maxillary transverse and sagittal deficiency in the early mixed dentition period

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Talapaneni

    2011-01-01

    Full Text Available Dentofacial Orthopedics directed to a hypoplastic maxilla in the prepubertal period redirects growth of the maxilla in the vertical, transverse and sagittal planes of space. The orthopedic correction of maxillary hypoplasia in the early mixed dentition period thus intercepts the establishment of permanent structural asymmetry in the mandible and helps in the achievement of optimal dentofacial esthetics. This paper presents the growth redirection in a hypoplastic maxilla of an 8-year-old girl with simultaneous rapid maxillary expansion and protraction headgear therapy for a period of 11 months which corrected the posterior unilateral cross-bite, the positional asymmetry of the mandible and established an orthognathic profile in the individual.

  10. Effectiveness of single-surface ART restorations in the permanent dentition: a meta-analysis.

    NARCIS (Netherlands)

    Frencken, J.E.F.M.; Hof, M.A. van 't; Amerongen, W.E. van; Holmgren, C.J.

    2004-01-01

    Over the past few years, there has been an increase in the number of studies reporting on various aspects of the Atraumatic Restorative Treatment (ART) approach. Five randomized clinical trials in which ART restorations with glass ionomers were compared with amalgam restorations in permanent teeth f

  11. Lateral occlusion schemes in natural and minimally restored permanent dentition: a systematic review.

    Science.gov (United States)

    Abduo, J; Tennant, M; McGeachie, J

    2013-10-01

    Clinicians commonly encounter the dilemma of which lateral occlusion schemes is most suitable for a specific patient. The aim of this review is to evaluate the prevalence of the lateral occlusion schemes that exist naturally. An electronic search was completed through PubMed (MEDLINE), Google Scholar and Cochrane Library. The search was confined to peer-reviewed studies published in English, up to April 2013. The literature search was supplemented by manual searching through the bibliography lists of the selected studies. The initial search retrieved a total of 575 studies. After applying the selection criteria, only 12 studies were suitable for inclusion. The Critical Appraisal Skills Programme (CASP) tools were utilised to appraise the quality of the studies. The prevalence of canine-guided, group function and balanced occlusions was reported. Overall, there was a clear variability between the studies. The prevalence of the lateral occlusion schemes appears to be influenced by the following factors: (i) the magnitude of excursion, (ii) an individual's age and (iii) the static occlusal relationship. During complete excursion, the canine-guided occlusion tends to be more frequently observed. After partial excursion, the most prevalent lateral occlusion schemes was group function occlusion. With ageing, the prevalence of canine-guided occlusion tends to be reduced and the prevalence of group function occlusion is increased. Dentition that is closer to Class II occlusion exhibits mainly canine-guided occlusion, while for Class III occlusion, group function occlusion is more prevalent. The studies revealed no relationship between the lateral occlusion schemes and TMD development.

  12. THE PREVALENCE OF OCCLUSION CLASSIFICATIONS OF PERMANENT DENTITION IN TEHRAN'S STUDENTS AGED 12 To 13 YEARS

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    A Jafari

    2008-11-01

    Full Text Available "nClassification of occlusion is the first step in diagnosing the relationship between the upper and lower jaw's teeth. Based on Angle's classification, occlusion is divided into three categories: class I, class II, and class III. The aim of this study was to determine the prevalence of occlusion categories, based on Angle's classification, in adolescents with permanent dentition in Tehran. This is an epidemiological cross sectional, randomized and descriptive study. Based on minimum rate of prevalence belonging to class III, number of cases was calculated and 1524 students, equal boys and girls, were studied. The prevalence of each classification in boys, girls and in total was determined. Among all cases, 79% were in class I occlusion; about 14.5% were in class II and 6.5% in class III. From Angle's 1899 study of prevalence of occlusion type until now, many studies have been done with different results. It seems that prevalence of occlusion type strongly depends on genetic factors and area of the study.

  13. Prevalence of supernumerary teeth in permanent dentition among patients attending a dental college in South Kerala: A pilot study

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    Devi Gopakumar

    2014-01-01

    Full Text Available Background: Supernumerary teeth are excess number of teeth formed as a result of disturbances occurring during odontogenesis. The objective of the study was to investigate the prevalence of supernumerary teeth in permanent dentition among patients attending a dental college in South Kerala. Materials and Methods: In this study, 11,141 subjects attending the out-patient department of PMS College of Dental Science and Research, Thiruvananthapuram, Kerala were examined for supernumerary teeth like mesiodens, paramolars, distomolars, third premolars, second laterals, and odontomes during the period May 2012-May 2013. Ethical clearance was obtained from the institutional ethical committee for the study. Results: The study showed a prevalence of 0.39% and a sex distribution of M:F equal to 2:1. The incidence of supernumerary teeth found was as follows: mesiodens (0.14%, paramolars (0.13%, third premolar (0.04%, distomolar (0.03%, extralateral (0.02%, and odontome (0.03%. The male:female gender predilection was as follows: mesiodens (3:1, paramolars (1.3:1, third premolar (4:1, distomolar (1:2, and odontome (2:1. Conclusion: This study showed a 0.39% prevalence of supernumerary teeth in this population.

  14. Occurrence of dental caries in primary and permanent dentition, oral health status and treatment needs among 12-15 year old school children of Jorpati VDC, Kathmandu.

    Science.gov (United States)

    Shrestha, N; Acharya, J; Sagtani, A R; Shrestha, R; Shrestha, S

    2014-12-01

    Dental caries occurrence, distribution, oral health status and corresponding treatment needs in 12 - 15 year old children are useful tools for evaluation of oral health. Dental caries status along with its treatment needs was recorded according to World Health Organization (WHO) index (1997) in 366 children from five schools within Jorpati Village Development Committee (VDC), Kathmandu. Dental caries was diagnosed in 156 (42.6%) children, out of which 122 (78.21%) had caries in permanent teeth, 26 (16.67%) had caries in primary teeth, and 8 (5.13%) had caries in both dentition. The age wise distribution of dental caries showed the highest prevalence among 12 year old students (23.8%) and the lowest among 15 year olds (3.8%). Among the female students (177), 43.5% showed presence of dental caries, while the prevalence among male students (179) was 41.8%.Out of the total number of teeth affected by dental caries (336), 273 (81.25%) were permanent teeth and 63 (18.75%) were primary teeth. The intra arch distribution of dental caries in permanent as well as primary dentition was statistically significant (P < 0.05). Restorative treatment (89.38%) was the main need in permanent dentition, and endodontic treatment (60.32%) in primary dentition. Chronologic enamel hypoplasia was found in 14 (3.83%) of the total population, and 62 (16.94%) required oral prophylaxis. These findings are significant as they can initiate further research in this area, which may help establish reliable baseline data for implementation of preventive oral health programs.

  15. Clinical decision-making for coronal caries management in the permanent dentition.

    Science.gov (United States)

    Anusavice, K

    2001-10-01

    Optimal conservative treatment decisions to prevent, arrest, and reverse tooth demineralization caused by caries require probability estimates on caries risk and treatment outcomes. This review is focused on the use of the best scientific evidence to recommend treatment strategies for management of coronal caries in permanent teeth as a function of caries risk. Evidence suggests that assigning therapeutic regimens to individuals according to their risk levels should yield a significantly greater probability of success and better cost effectiveness than applying identical treatments to all patients independent of risk. Depending on caries risk levels, treatment decisions based on risk can minimize unnecessary surgical intervention by incorporating the best evidence to prescribe treatment regimens for the use of fluoride-releasing agents, sealants, chlorhexidine, or combinations of these products.

  16. Pattern of traumatic dental injuries in the permanent dentition among children, adolescents, and adults

    DEFF Research Database (Denmark)

    Lauridsen, Eva; Hermann, Nuno Vibe; Gerds, Thomas Alexander;

    2012-01-01

    BACKGROUND: Traumatic dental injuries (TDI) comprise six types of luxation and seven types of tooth fractures. The risk of pulp necrosis is increased in teeth with combination injuries where fractures and luxations occur concomitantly. AIM: To report and compare the distributions of luxations...... and fracture types among children, adolescents, and adults, and to analyze the distribution and prevalence of combination injuries. MATERIAL AND METHOD: The study group included 4754 patients (3186 men and 1568 women) with 10 166 traumatized permanent incisors treated at Copenhagen University Hospital...... (children 5.7%, adolescents 10.9%, adults 13.0%, P traumatized teeth (n = 3212) had sustained a combination of a fracture and a luxation injury. The luxation types most frequently presenting with a concomitant crown fracture were concussion (57.9%), intrusion (47...

  17. Distribution of sagittal occlusal relationships in different stages of dentition

    Directory of Open Access Journals (Sweden)

    Emine KAYGISIZ

    2015-01-01

    Full Text Available The aim of this study was to assess the distribution of sagittal occlusal relationships in different dentition periods in a Turkish sample group. In total, 1,110 patients (561 females, 549 males aged 4.6-23 years were randomly chosen after intraoral clinical examination. The subjects were classified according to their sagittal occlusal relationships and four dentition stages –deciduous, early mixed, late mixed, and permanent dentition. The statistical significance of the occurrence of malocclusion types in dentition stages was evaluated by Chi-square and Fischer’s exact tests. Class I malocclusion was observed at the highest rate in all dentition stages. Class III malocclusion was observed at the highest rate in the permanent dentition, whereas Class II malocclusion was observed at the highest rate in the late mixed dentition. The rates of Class I, II, and III malocclusions were similar in males and females. Our study reveals that the prevalence of malocclusion and need for orthodontic treatment has increased in the population towards the permanent dentition.

  18. Linear Odontometric Analysis of Permanent Dentition as A Forensic Aid: A Retrospective Study

    Science.gov (United States)

    Nair, Sunil Sukumaran; Gopakumar, Devi; Kurian, Nisha; Parameswar, Arjun; Baby, Tibin Kaithappillil

    2016-01-01

    Introduction Sex determination in forensic anthropology is an essential step for medico-legal purposes and crucial for identification as the number of possible matches is reduced to 50%. Teeth are an excellent material for anthropological, genetic, odontological and forensic investigations as they are known to resist a variety of ante-mortem and post-mortem insults. Sexual dimorphism in tooth size and the accuracy of odontometric sex prediction is found to vary in different population and therefore it is necessary to determine specific population values in order to make identification possible. Hence, the present study was undertaken to evaluate the existence of sexual dimorphism in South Kerala population. Aim To evaluate and estimate the degree of odontometric sexual dimorphism in all permanent teeth except third molars and the variations in odontometric dimensions between the left and right side teeth of the maxillary and mandibular arches in male and female groups. Materials and Methods The MesioDistal (MD) and BuccoLingual (BL) measurements of 28 teeth were estimated from the preorthodontic casts of 132 subjects; male group (66 males) and female group (66 females) of age range 15-25 years using digital Verniers’ Caliper. The data obtained were analysed using SPSS version 17 and the Students’ t-test for two independent samples. Results The MesioDistal (MD) and BuccoLingual (BL) parameters of all permanent teeth in the study group showed sexual dimorphism. Over 39% of the tooth variables showed reverse dimorphism. The comparison of mean values of MD and BL diameters of the maxillary and mandibular, right and left side teeth in male and female groups showed statistical significance in males whereas females show non-significant values in both MD and BL diameters. Conclusion The study showed a varied percentage of sexual dimorphism and variation in the mean values of MD and BL dimensions in males, but not in females between right and left side teeth of the

  19. Mesiodens in primary, mixed and permanent dentitions: a clinical and radiographic study.

    Science.gov (United States)

    Ersin, Nazan Kocatas; Candan, Umit; Alpoz, Ali Riza; Akay, Cemal

    2004-01-01

    The term mesiodens refers to a supernumerary tooth located between the maxillary central incisors. The aim of the study was to investigate the characteristics of mesiodens among children in Turkey. The study population involved 24 children who attended the Department of Pediatric Dentistry, Ege University for dental problems. The characteristics of mesiodens were obtained from clinical and radiographic examinations. Results showed that twenty-four patients had thirty-four mesiodens for an average of 1.42 mesiodens per person. Males were affected approximately 3 times more frequently in comparison with females. Forty-two percent of the patients had bilateral mesiodens. All of the mesiodens were conical in shape and 91% were in the downward position. The age and sex distribution, location, direction, eruption of mesiodens and effects on permanent maxillary incisors were also presented in this study. It could be concluded that, delayed, ectopic or asymmetric eruption of the central incisors should alert the clinician to the possibility of a mesiodens.

  20. Prevalence and Characteristics of Tooth Agenesis in Permanent Dentition of Subjects from Tîrgu Mureș

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    Bernadette Kerekes-Máthé

    2013-08-01

    Full Text Available Background: Identification of the characteristics of tooth agenesis is an important component in the understanding of the ethiology of this common developmental dental anomaly. The aim of the present study was to determine the prevalence and the characteristics of tooth agenesis among patients from Tîrgu Mureș. Material and method: The present study is retrospective and descriptive, based on the evaluation of the patient’s dental records from 2004 to 2012 belonging to a pediatric dental office from Tîrgu Mureș. Orthopantomograms and anamnestic data of 947 children and young adults (365 male and 582 female were analyzed. Results: The prevalence of tooth agenesis, excluding third molars, was 7.39%. The difference between the genders was statistically not significant (p = 0.09. The most frequently missing teeth were the upper second incisors, followed by the lower second premolars. The difference between the distribution of agenesis in the upper and lower jaws was statistically significant (p <0.0001. The distribution of dental agenesis between the anterior region and the lateral region of the maxilla and the mandible showed significant differences (p <0.0001. Symmetrical distribution of tooth agenesis was found more frequently (54.54% than assymetrical distribution. Conclusions: The maxillary anterior region and the mandibular lateral region were the most affected by dental agenesis in the permanent dentition of the studied population. The maxilla was more affected than the mandible and bilateral forms of agenesis were more frequently than unilateral forms. The more extreme forms of agenesis were found amongst female

  1. Evaluating the Stability of Open Bite Treatments and Its Predictive Factors in the Retention Phase during Permanent Dentition

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    Parisa Salehi

    2015-03-01

    Full Text Available Statement of the Problem: Orthodontists often find challenges in treating the anterior open bite and maintaining the results. Purpose: This retrospective study was aimed to evaluate the stability of corrected open bite in the retention phase during permanent dentition. Materials and Method: A total number of 37 patients, including 20 males and 17 females, with the mean age of 18±2.1 years at the beginning of the treatment were studied after correction of the anterior open bite. Overbites of the patients were measured from their lateral cephalograms before (T1, at the end (T2 and at least 3 years after the end of the treatment in the presence of their fixed retainers (T3.The mean overbite changes and the number of patients with open bite, due to treatment relapse, at T3 were calculated. The relationship between the pre-treatment factors and the treatment relapse was assessed at T1 and T2. Also the effects of treatment methods, extraction and adjunctive use of removable appliances on the post-treatment relapse were evaluated. Results: The mean overbite change during the post-treatment period was -0.46±0.7 mm and six patients (16.2% had relapse in the follow-up recall. Cephalometric Jaraback index showed statistically significant, but weak correlation with overbite changes after the treatment (p= 0.035; r= -0.353. No significant difference was found between the extraction and non-extraction groups (p= 0.117 the use and the type of the removable appliances (p= 0.801. Conclusion: Fixed retainers alone are insufficient for stabilizing the results of corrected open bite. The change of overbite in the retention phase could not be predicted from cephalometric measurements. Extraction and use of adjunctive removable appliance did not have any effect on the treatment relapse.

  2. Prediction of Mesiodistal Width of Unerupted Lateral Incisors, Canines and Premolars in Orthodontic Patients in Early Mixed Dentition Period

    Science.gov (United States)

    Toodehzaeim, Mohammad Hossein; Haerian, Alireza

    2016-01-01

    Objectives: Proper diagnosis and prevention of malocclusion are superior to treatment. Discrepancy between arch length and tooth size in mixed dentition period is a condition requiring timely diagnosis. Estimating the mesiodistal width of unerupted teeth according to the size of erupted ones can lead to earlier diagnosis of malocclusion. On the other hand, the best timing for serial extractions is before the eruption of lateral incisors. The aim of this study was to present prediction formulas for mesiodistal width of unerupted lateral incisors, canines and premolars in an Iranian population based on the width of erupted permanent mandibular central incisors and maxillary first molars. Materials and Methods: A total of 120 dental models (60 males, 60 females) of orthodontic patients between 11–25 years were evaluated in Yazd city. The measurements were made by a digital caliper on the widest mesiodistal width of teeth at the interproximal contacts. Data were analyzed to calculate the prediction equation. Results: The prediction equation in the upper jaw was y=0.57x+10.82 for males, y=0.7x+6.37 for females and y=0.64x+8.46 for both sexes. The equation for the lower jaw was y=0.76x+2.86 for males, y=0.74x+3.53 for females and y=0.77x+2.7 for both sexes. Conclusions: The prediction equations suggested in this study can predict the mesiodistal width of unerupted lateral incisors, canines and premolars in an Iranian population in early mixed dentition period without taking radiographs. PMID:28243298

  3. [What is the relation between the presence of caries in the deciduous dentition and the chronology of the eruption of the permanent teeth?].

    Science.gov (United States)

    Leroy, Roos; Declerck, Dominique

    2004-01-01

    Based on data obtained from a prospective epidemiological study in a random sample of 4468 Flemish children, accurate emergence ages for permanent teeth could be established. When data on permanent tooth emergence in different populations are compared, differences are most pronounced for premolars. Several authors hypothesised that this difference could be explained by a difference in caries experience in the primary molars. The purpose of this study was to quantify the effect of caries experience in a primary molar on the timing of emergence of its successor. The results indicate that the emergence of the premolars was accelerated by 2 to 8 months when its predecessor had been decayed and or filled but had not been extracted. Premature loss of maxillary primary molars resulted in a significant acceleration of the emergence of the premolars; this was not observed in the mandible. In conclusion, when considering permanent tooth emergence ages, caries experience in the primary dentition should be taken into account.

  4. Early class III management in deciduous dentition using reverse twin block

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    S S Sargod

    2013-01-01

    Full Text Available Class III malocclusion poses a challenging dilemma for the clinician because these children have of growth patterns that differ from that of children with class I malocclusion. The mandible grows more rapidly than the maxilla, exacerbating the class III malocclusion as the child go through adolescence. Ever since Clark described a version of the twin block, it has steadily gained popularity in the management of early class III malocclusion in children. However, not many cases are reported in the literature on its use in deciduous dentition. This article tries to provide an insight into the reverse twin block appliance and reports two cases of early class III malocclusion treated using reverse twin block.

  5. Frequency and variability of dental morphology in deciduous and permanent dentition of a Nasa indigenous group in the municipality of Morales, Cauca, Colombia

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    Eider Díaz

    2014-04-01

    Full Text Available Objectives:To determine the frequency, variability, sexual dimorphism and bilateral symmetry of fourteen dental crown traits in the deciduous and permanent dentition of 60 dental models (35 women and 25 men obtained from a native, indigenous group of Nasa school children of the Musse Ukue group in the municipality of Morales, Department of Cauca, Colombia.Material and methods:This is a quantitative descriptive, cross-sectional study that characterizes dental morphology by means of the systems for temporary dentition from Dahlberg (winging, and ASUDAS (crowding, reduction of hypocone, metaconule and cusp 6, Hanihara (central and lateral incisors in shovel-shape and cusp 7, Sciulli (double bit, layered fold protostylid, cusp pattern and cusp number and Grine (Carabelli trait; and in permanent dentition from ASUDAS (Winging, crowding, central and lateral incisors in shovel-shape and double shovel-shape, Carabelli trait, hypocone reduction, metaconule, cusp pattern, cusp number, layered fold protostylid, cusp 6 and cusp 7.Results:The most frequent dental crown features were the shovel-shaped form, grooved and fossa forms of the Carabelli trait, metaconule, cusp pattern Y6, layered fold, protostylid (point P and cusp 6. Sexual dimorphism was not observed and there was bilateral symmetry in the expression of these features.Conclusions:The sample studied presented a great affinity with ethnic groups belonging to the Mongoloid Dental Complex due to the frequency (expression and variability (gradation of the tooth crown traits, upper incisors, the Carabelli trait, the protostylid, cusp 6 and cusp 7. The influence of the Caucasoide Dental Complex associated with ethno-historical processes cannot be ruled out. 

  6. Impact of parent-related factors on dental caries in the permanent dentition of 6-12-year-old children: A systematic review.

    Science.gov (United States)

    Kumar, Santhosh; Tadakamadla, Jyothi; Kroon, Jeroen; Johnson, Newell W

    2016-03-01

    To synthesise data from the literature on the effects of various parent-related characteristics (socio-demographic, behavioural and family environment) on dental caries in the permanent dentition of children. Available studies in which the effects of parent-related characteristics on dental caries experience in the permanent dentition of children aged 6-12 years were evaluated. PubMed, Medline via OVID and CINAHL Plus via EBSCO, restricted to scientific articles, were searched in April 2015. English language and time filters (articles published from 2000) were used. A total of 4162 titles were retrieved, of which 2578 remained after duplicates were removed. After review of titles and their abstracts by two independent reviewers, 114 articles were considered relevant for full text review. Of these, 48 were considered for final inclusion. Data extraction was performed by two authors using piloted data extraction sheets. Most of the literature on determinants of dental caries has been limited to socio-economic and behavioural aspects: we found few studies evaluating the effects of family environment and parental oral hygiene behaviour. Children belonging to lower socio-economic classes experienced more caries. In more than half the studies, children of highly educated, professional and high income parents were at lower risk for dental caries. There were conflicting results from studies on the effect of variables related to family environment, parents' oral hygiene behaviour and parent's disease status on dental caries in their children. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Malocclusion and early orthodontic treatment requirements in the mixed dentitions of a population of Nigerian children

    Science.gov (United States)

    daCosta, Oluranti Olatokunbo; Aikins, Elfleda Angelina; Isiekwe, Gerald Ikenna; Adediran, Virginia Efunyemi

    2016-01-01

    Introduction: The aims of this study were to establish the prevalence of dental features that indicate a need for early intervention and to ascertain the prevalence of different methods of early treatment among a population of Nigerian children in mixed dentition. Methods: Occlusal relationships were evaluated in 101 children in mixed dentition between the ages of 6 and 12 years who presented at the Orthodontic Unit, Department of Child Dental Health, Lagos University Teaching Hospital over a 2 years period. The need for different modes of early orthodontic treatment was also recorded. Results: Anterior tooth rotations (61.4%) and increased overjet (44.6%) were the most prevalent occlusal anomalies. Others included deep bite (31.7%), reverse overjet (13.9%), and anterior open bite (14.8%). Severe maxillary spacing and crowding were exhibited in 12.0% and 5.0%, respectively. About a third (35.7%) of the subjects presented with crossbite while lip incompetence was observed in 43.6% of the subjects. About 44% of the subjects also presented with various oral habits with digit (15.8%) and lip sucking (9.9%) being the most prevalent. Subjects were recommended for treatment with 2 by 4 fixed orthodontic appliances (22.3%), habit breakers (20.7%), removable orthodontic appliances (16.5%), and extractions (15.7%). Conclusions: Increased overjet and anterior tooth rotation were the majority of occlusal anomalies seen, which are not only esthetically displeasing but may also cause an increased susceptibility to trauma to these teeth. Treatment options varied from extractions only to the use of appliance therapy. PMID:27556019

  8. DENTAL EROSION IN PRIMARY DENTITION- A REVIEW

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    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.

  9. Mesiodens in the primary dentition--a case report.

    Science.gov (United States)

    Prabhu, N T; Rebecca, J; Munshi, A K

    1998-09-01

    Supernumerary teeth are among the most significant dental anomalies affecting the primary and the permanent dentitions. Mesiodens is a supernumerary tooth with a cone shaped crown and a short root. Though it occurs frequently in the permanent dentition, it is extremely rare in the primary dentition. The exact etiology is still obscure and not well understood. Supernumerary teeth occur as isolated dental findings or as part of a syndrome. The frequency with which supernumerary teeth occur and the effects they have on development of normal occlusion justify the radiographic examination of preschool children. Early removal of such teeth is recommended if they impede the eruption of adjacent permanent teeth, appear inverted or rudimentary, associated with certain pathologic conditions or are symptomatic.

  10. Three-dimensional analysis of the early development of the dentition

    Science.gov (United States)

    Peterkova, R; Hovorakova, M; Peterka, M; Lesot, H

    2014-01-01

    Tooth development has attracted the attention of researchers since the 19th century. It became obvious even then that morphogenesis could not fully be appreciated from two-dimensional histological sections. Therefore, methods of three-dimensional (3D) reconstructions were employed to visualize the surface morphology of developing structures and to help appreciate the complexity of early tooth morphogenesis. The present review surveys the data provided by computer-aided 3D analyses to update classical knowledge of early odontogenesis in the laboratory mouse and in humans. 3D reconstructions have demonstrated that odontogenesis in the early stages is a complex process which also includes the development of rudimentary odontogenic structures with different fates. Their developmental, evolutionary, and pathological aspects are discussed. The combination of in situ hybridization and 3D reconstruction have demonstrated the temporo-spatial dynamics of the signalling centres that reflect transient existence of rudimentary tooth primordia at loci where teeth were present in ancestors. The rudiments can rescue their suppressed development and revitalize, and then their subsequent autonomous development can give rise to oral pathologies. This shows that tooth-forming potential in mammals can be greater than that observed from their functional dentitions. From this perspective, the mouse rudimentary tooth primordia represent a natural model to test possibilities of tooth regeneration. PMID:24495023

  11. Three-dimensional analysis of the early development of the dentition.

    Science.gov (United States)

    Peterkova, R; Hovorakova, M; Peterka, M; Lesot, H

    2014-06-01

    Tooth development has attracted the attention of researchers since the 19th century. It became obvious even then that morphogenesis could not fully be appreciated from two-dimensional histological sections. Therefore, methods of three-dimensional (3D) reconstructions were employed to visualize the surface morphology of developing structures and to help appreciate the complexity of early tooth morphogenesis. The present review surveys the data provided by computer-aided 3D analyses to update classical knowledge of early odontogenesis in the laboratory mouse and in humans. 3D reconstructions have demonstrated that odontogenesis in the early stages is a complex process which also includes the development of rudimentary odontogenic structures with different fates. Their developmental, evolutionary, and pathological aspects are discussed. The combination of in situ hybridization and 3D reconstruction have demonstrated the temporo-spatial dynamics of the signalling centres that reflect transient existence of rudimentary tooth primordia at loci where teeth were present in ancestors. The rudiments can rescue their suppressed development and revitalize, and then their subsequent autonomous development can give rise to oral pathologies. This shows that tooth-forming potential in mammals can be greater than that observed from their functional dentitions. From this perspective, the mouse rudimentary tooth primordia represent a natural model to test possibilities of tooth regeneration. © 2014 Australian Dental Association.

  12. Individual-based prediction of the size of the supporting zones in the permanent dentition. A comparison of the Moyers method with a unitary prediction value.

    Science.gov (United States)

    Pancherz, H; Schäffer, C

    1999-01-01

    The aims of this individual-based study were 1. to assess the actual space requirements of the permanent canines and premolars, 2. to test the reliability of the Moyers method in predicting a space deficiency at the 75% confidence level and 3. to try to find a reliable unitary prediction value (= unitary value) as a possible substitute for the calculated Moyers values. Dental cast measurements were taken of the permanent dentition of 100 females and 100 males. The average sum of the widths of the maxillary and mandibular permanent canines and premolars was 20.8 mm (17.3 to 24.3 mm). The Moyers method could predict a maxillary space deficiency in 77.5% and a mandibular space deficiency in 65.5% of the subjects. The unitary value of 22.0 mm made it possible to predict a space deficiency in 83.5% of the subjects. The unitary value thus had a higher confidence level (83.5%) than the 75% level stated by Moyers and might thus substitute the calculated Moyers values. Furthermore, the unitary value is easy and quick to handle.

  13. Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings

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    Daniela Gamba Garib

    2014-06-01

    Full Text Available OBJECTIVE: This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME in the mixed dentition by means of computed tomography (CT. METHODS: The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age (mean age of 8.1 years presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p < 0.05. RESULTS: Thickness of buccal and lingual bone plates of posterior teeth remained unchanged during the expansion period, except for deciduous second molars which showed a slight reduction in bone thickness at the distal region of its buccal aspect. Buccal bone dehiscences were not observed in the supporting teeth after expansion. CONCLUSION: RME performed in mixed dentition did not produce immediate undesirable effects on periodontal bone tissues.

  14. The bonding bite plate combined with the face mask protracting maxilla to treat skeletal crossbite in the early mixed dentition

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To evaluate the orthopedic effects of a new method to treat skeletal crossbite in the early mixed dentition. Methods:Twenty cases (5.8-7.5 years old ) with skeletal crossbite were treated by bonding the bite plate combined with the face mask protracting the upper jaw. Cephalometric radiographs were taken and analyzed before and after treatments. Results: On average, in all 20 cases the maxilla was moved by 2.06 mm forward; the mandible was turned 2.45° downward and backward; the skeletal crossbites were corrected and the facial profiles were improved satisfactorily. The period of treatment was conducted for 1.7 months on average. Conclusion: A good effect can be achieved by bonding bite plate combined with the face mask protracting the upper jaw to treat skeletal crossbite in the early mixed dentition, which will benefit the craniofacial growth and the development of young children.

  15. Molariform Mesiodens in Primary Dentition

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    Sachin B. Mangalekar

    2013-01-01

    Full Text Available Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch, and incidence of molariform mesiodens in the maxillary midline is rare in permanent dentition and extremely uncommon in primary dentition. A midline supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent central incisors which will further alter occlusion and may compromise esthetics and formation of dentigerous cysts. This paper reports a rare case of the presence of a molariform mesiodens in the primary dentition. On clinical and radiographic examination, flaring of the primary central incisors was seen, with a molariform mesiodens consisting of multiple lobes or tubercles on the occlusal surface with the well-formed root. The treatment plan consisted of the extraction of the supernumerary tooth and regular observation of permanent central incisors for proper eruption and alignment.

  16. Molariform mesiodens in primary dentition.

    Science.gov (United States)

    Mangalekar, Sachin B; Ahmed, Tajammul; Zakirulla, M; Shivappa, Halawar Sangmesh; Bheemappa, F B; Yavagal, Chandrashekar

    2013-01-01

    Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch, and incidence of molariform mesiodens in the maxillary midline is rare in permanent dentition and extremely uncommon in primary dentition. A midline supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent central incisors which will further alter occlusion and may compromise esthetics and formation of dentigerous cysts. This paper reports a rare case of the presence of a molariform mesiodens in the primary dentition. On clinical and radiographic examination, flaring of the primary central incisors was seen, with a molariform mesiodens consisting of multiple lobes or tubercles on the occlusal surface with the well-formed root. The treatment plan consisted of the extraction of the supernumerary tooth and regular observation of permanent central incisors for proper eruption and alignment.

  17. Comparison of dentin hardness between conventional drill and chemomechanical methods in primary and permanent dentition using nanoindenter

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    M Kruthika

    2016-01-01

    Full Text Available Introduction: Latest theories regarding the rationale of carious dentin removal are beginning to question the amount of tissue that needs to be excavated to successfully treat a carious tooth. It is not always easy to make a decision at which point to stop excavation because there is an apparent lack of objective clinical markers. However, hardness of dentin might be a useful marker in this respect. Nanoindentation test is a variety of indentation hardness test applied to small volumes such as teeth which contain nanosized structures. Aims: To compare and evaluate the nanohardness of dentin after chemomechanical (Carie-care method of caries removal with the conventional (rotary instrument method of caries removal in primary and permanent teeth using nanoindenter. Materials and Methods: An in vitro randomized controlled trial was conducted using fifteen primary and fifteen permanent extracted molars with active carious lesion extending into the dentin. The primary and permanent molars were further randomly divided into two subgroups by sectioning the samples into two halves. Caries removal was done using conventional drill (CD and chemomechanical caries removal (CMCR (Carie-care methods. Following the caries removal, the test specimens were subjected for evaluation of nanohardness of dentin using nanoindenter. Student's t-test, analysis of variance, and Bonferroni test were used. Results: Statistically significant difference between the 4 groups with a P < 0.05 was obtained. Conclusions: After caries removal, the hardness of remaining dentin was found to be harder after CMCR method than with the CD method in both primary and permanent teeth, and the remaining dentin of the permanent teeth was found to be harder than the primary teeth after caries removal.

  18. Defectos del esmalte, caries en dentición primaria, fuentes de fluoruro y su relación con caries en dientes permanentes Enamel defects, caries in primary dentition and fluoride sources: relationship with caries in permanent teeth

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    Ana Alicia Vallejos-Sánchez

    2007-06-01

    Full Text Available Objetivo: Explorar la relación entre la presencia de defectos del esmalte (DE, la experiencia de caries en la dentición temporal, y la exposición a diversas fuentes de fluoruros, con la presencia de caries en la dentición permanente de niños con dentición mixta. Material y métodos: Se realizó un estudio transversal en 713 sujetos de 6-9 años de edad de 4 escuelas de Campeche, México, mediante un cuestionario dirigido a las madres, y un examen clínico bucal a los niños. La variable dependiente fue la prevalencia de caries en la dentición permanente. Resultados: El promedio de dientes temporales cariados, extraídos y obturados (ceod y dientes permanentes cariados, perdidos y obturados (CPOD fue de 2,48 (2,82 (ceod > 0 = 58,9% y 0,40 (0,98 (CPOD > 0 = 18,2%, respectivamente. El índice SiC (índice de caries significativa, calculado en la dentición temporal fue de 5,85 para los niños de 6 años de edad. En el análisis de regresión logística multivariado permanecieron significativas, después de ajustar por variables de exposición a fluoruros, la mayor edad (odds ratio [OR] = 2,99, el ceod > 0 (OR = 5,46, la menor escolaridad de la madre (OR = 1,57 y una interacción entre sexo y defectos del esmalte. Conclusiones: Las caries en la dentición temporal y permanente fueron relativamente menores que las observaciones publicadas por otros estudios en México. Los resultados confirmaron que la caries en la dentición temporal se asoció fuertemente con la caries en la dentición permanente. No hubo una relación significativa entre las fuentes de fluoruro y la caries dental en la dentición permanente.Objective: To examine the relationship between the presence of enamel defects, dental caries in primary teeth, and exposure to various fluoride technologies and the presence of dental caries in permanent teeth in children with mixed dentition. Materials and methods: A cross-sectional study was conducted in 713 children aged 6-9 years old

  19. Maturasi dan erupsi gigi permanen pada anak periode gigi pergantian (The maturition and eruption of permanent teeth in mixed dentition children

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    Sri Kuswandari

    2014-06-01

    Full Text Available Background: Tooth eruption might used as predictor of child age when the chronologic age is unknown. Beside the dental maturity, tooth eruption is also influenced by some factors, such as caries and tooth extraction. Purpose: The aim of this research was to examine the relationship of maturity and eruption of permanent teeth with chronologic age in mixed dentition period children. Methods: The subjects were patients of Prof. Soedomo Dental Hospital Pediatric Dental Clinic, consist of 38 boys and 39 girls in the aged of 6-12 years. The tooth eruption data was taken by counting the permanent teeth in intra oral examination. The dental maturity was assessed by Dermijian method from dental panoramic radiology. The data were statistical analyzed by regresion-correlation and t-test program of SPSS 16.0 for Windows. Results: Maturation of permanent teeth in each of age group was more advanced in girls than boys. However, only groups of 7, 8 and 11 years were showed significant different (p<0.05, while for tooth eruption there was no significant difference (p>0.05. The coefficient correlation between tooth eruption, chronologic age and dental maturation scores were relative high, between 0.75–0.86 (p<0.01. The contribution of chronologic age and dental maturation to predict tooth eruption (R2 were 58–73.6%. The Dermijian method predicted age 0.83 years higher. Conclusion: There were close relationship between chronologic age, Dermijian method dental maturity, and eruption of permanen tooth, and could be used as predictor for eruption of permanent teeth in the mixed dentition period children. The Dermijian method predicted 0.83 years older than the chronologic age.Latar belakang: Erupsi gigi sering digunakan untuk memperkirakan umur anak. Selain maturasi gigi, erupsi gigi juga dipengaruhi oleh faktor, seperti karies dan pencabutan gigi. Tujuan: Penelitian ini bertujuan untuk meneliti hubungan antara maturasi dan erupsi gigi permanen dengan umur pada

  20. Comparative Analysis of the Amount of Plaque Formation and Associated Gingival Inflammation in Deciduous, Mixed and Permanent Dentition

    OpenAIRE

    Agarwal, Abhay; Rehani, Usha; Adlakha, Vivek; Kaushik, Mayur; Kaushik, Noopur

    2009-01-01

    Periodontal diseases in children and adolescents comprise mainly of gingivitis. Gingivitis is an inflammation involving the gingival tissues next to the teeth. Marginal gingivitis is the most common form of periodontal disease and starts in early childhood. However, severe gingivitis is relatively uncommon in children, although a large population has a mild, reversible type of gingivitis. The major etiologic factors associated with gingivitis and more significantly periodontal diseases are un...

  1. Treatment of ectopic first permanent molar teeth.

    LENUS (Irish Health Repository)

    Hennessy, Joe

    2012-11-01

    Ectopic eruption of the first permanent molar is a relatively common occurence in the developing dentition. A range of treatment options are available to the clinician provided that diagnosis is made early. Non-treatment can result in premature exfoliation of the second primary molar, space loss and impaction of the second premolar. This paper will describe the management of ectopic first permanent molars, using clinical examples to illustrate the available treatment options. CLINICAL RELEVANCE: This paper is relevant to every general dental practitioner who treats patients in mixed dentition.

  2. A retrospective study of Class II mixed-dentition treatment.

    Science.gov (United States)

    Oh, Heesoo; Baumrind, Sheldon; Korn, Edward L; Dugoni, Steven; Boero, Roger; Aubert, Maryse; Boyd, Robert

    2017-01-01

    To consider the effectiveness of early treatment using one mixed-dentition approach to the correction of moderate and severe Class II malocclusions. Three groups of Class II subjects were included in this retrospective study: an early treatment (EarlyTx) group that first presented at age 7 to 9.5 years (n = 54), a late treatment (LateTx) group whose first orthodontic visit occurred between ages 12 and 15 (n = 58), and an untreated Class II (UnTx) group to assess the pretreatment comparability of the two treated groups (n = 51). Thirteen conventional cephalometric measurements were reported for each group and Class II molar severity was measured on the study casts of the EarlyTx and LateTx groups. Successful Class II correction was observed in approximately three quarters of both the EarlyTx group and the LateTx group at the end of treatment. EarlyTx patients had fewer permanent teeth extracted than did the LateTx patients (5.6% vs 37.9%, P < .001) and spent less time in full-bonded appliance therapy in the permanent dentition than did LateTx patients (1.7 ± 0.8 vs 2.6 ± 0.7years, P < .001). When supervision time is included, the EarlyTx group had longer total treatment time and averaged more visits than did the LateTx group (53.1 ± 18. 8 vs 33.7 ± 8.3, P < .0001). Fifty-five percent of the LateTx extraction cases involved removal of the maxillary first premolars only and were finished in a Class II molar relationship. EarlyTx comprehensive mixed-dentition treatment was an effective modality for early correction of Class II malocclusions.

  3. DENTAL EROSION IN PRIMARY DENTITION- A REVIEW

    OpenAIRE

    Rafi Shaik

    2017-01-01

    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 c...

  4. Pendulum Therapy of Molar Distalization in Mixed Dentition.

    Science.gov (United States)

    Patil, Raju Umaji; Prakash, Amit; Agarwal, Anshu

    2016-01-01

    Early and timely pedo-orthodontic treatment is aimed at eliminating the disturbances of skeletal or dentoalveolar development, to harmonize the stomatognathic system before the full eruption of all permanent teeth. The advantages of pendulum appliance are its minimal dependence on patient's compliance (child cooperation), ease of fabrication, onetime activation and adjustment of the springs if necessary to correct minor transverse and vertical molar positions. This article reports a successful treatment method of class II malocclusion with pendulum appliance in mixed dentition phase. Distalization of maxillary molar was done, followed by guidance of canine impaction orthodontically and other dental correction using 0.022 MBT appliances. Posttreatment results were stable and remarkable. How to cite this article: Patil RU, Prakash A, Agarwal A. Pendulum Therapy of Molar Distalization in Mixed Dentition. Int J Clin Pediatr Dent 2016;9(1):67-73.

  5. The functional significance of morphological changes in the dentitions of early mammals.

    Science.gov (United States)

    Conith, Andrew J; Imburgia, Michael J; Crosby, Alfred J; Dumont, Elizabeth R

    2016-11-01

    The Mesozoic marked a time of experimentation in the tooth morphology of early mammals. One particular experiment involved the movement of three points, or cusps, on the surface of a molar tooth from a line into a triangle. This transition is exemplified by two extinct insectivorous mammals, Morganucodon (cusps in a line) and Kuehneotherium (cusps in a triangle). Here we test whether this difference in cusp arrangement, alongside cusp heights and angles between cusps, is associated with differences in the ability of the teeth to fracture proxy-insect prey. We gathered measurements from molar teeth of both species and used them to create physical models. We then measured the force, time and energy at fracture and peak force, and the amount of damage inflicted by the models on hard and soft gels encased in a tough film that mimicked the material properties of insects. The Morganucodon model required less force and energy to fracture hard gels and reach peak force compared with KuehneotheriumKuehneotherium required a similar time, force and energy to fracture soft gels but reduced the time, force and energy to reach peak force. More importantly, Kuehneotherium also inflicted more damage to both the hard and the soft gels. These results suggest that changes in dental morphology in some early mammals was driven primarily by selection for maximizing damage, and secondarily for maximizing biomechanical efficiency for a given food material property. © 2016 The Author(s).

  6. One Phase versus Two Phase Treatment in Mixed Dentition: A Critical Review

    Science.gov (United States)

    Suresh, M; Ratnaditya, Akurathi; Kattimani, Vivekanand S; Karpe, Shameem

    2015-01-01

    The mixed dentition is the developmental period after the permanent first molars and incisors have erupted, and before the remaining deciduous teeth are lost. Phase I treatment is usually done early in this period. Mixed dentition treatment goals often focus on skeletal rather than dental correction. To design a treatment plan, the clinician must understand the growth and development patterns, and the known effects of the chosen treatment modality. Jaw growth affects orthodontic treatment, usually favorably, but sometimes unfavorably. When and how much growth will occur is completely unpredictable. However, we know some useful facts about jaw growth in the mixed dentition. The two areas that remain controversial in the orthodontic literature are the treatment of crowding and of Class II malocclusions in the mixed dentition. Is there a benefit to early treatment for these problems? This question has yet to be fully answered by researchers. Hence, we planned for review of all available literature to come to a consensus about preventive or interceptive orthodontics or in other words Phase 1 and Phase 2 treatment. The clinician can diagnose and intercept certain developing problems with early treatment. Many other cases should be supervised, but not treated until the permanent teeth are in place. We must base our decision to treat on experience, knowledge of growth and dental development, and research. PMID:26464559

  7. Treatment of anterior crossbite in the primary dentition with esthetic crowns: report of 3 cases.

    Science.gov (United States)

    Ramirez-Yañez, German

    2011-01-01

    Anterior crossbite is a sagittal malocclusion occurring in approximately 4 to 5% of children with primary dentition. Although self-correction may occur, treating an anterior crossbite as early as possible has been proposed to prevent problems in the transitional and permanent dentitions. The purpose of this paper is to present an optional restorative treatment used in 3 cases where an anterior crossbite was treated by restoring the primary maxillary incisors with esthetic pediatric strip crowns. In all 3 cases, the crossbite was successfully treated by using the proposed technique over 1 to 2 weeks. A 6-month follow-up showed that the occlusion stabilized into a sagittal normal relationship, permitting normal dentofacial growth and development to continue. The technique presented here can be added to the armamentarium of pediatric dentists and general practitioners to correct anterior crossbites diagnosed in the primary dentition.

  8. Orden de emergencia de la dentición permanente en niños del municipio de Santa Clara: Parte II Emergence order of permanent dentition in children from the Santa Clara municipality: Part II

    Directory of Open Access Journals (Sweden)

    Armando San Miguel Pentón

    2011-09-01

    Full Text Available Se realizó un estudio epidemiológico descriptivo transversal de la dentición permanente en la provincia de Santa Clara desde el año 2005 al año 2009, con el objetivo de determinar el orden de emergencia de la dentición permanente. El universo fue de 45 724 infantes de ambos sexos entre los 4 y 14 años de edad. La muestra fue de 1 769 individuos. Se hallaron los percentiles de emergencia y a partir del percentil 50 se estableció el orden. Se compararon los dientes para cada grupo eruptivo y se estudió la simetría. Se estableció el orden de emergencia. Hubo diferencias para el orden entre los sexos, hemiarcadas y con las tablas de otros autores. Los dientes más simétricos fueron los incisivos y los primeros molares. Se concluyó que no siempre los dientes inferiores brotaron antes que sus homólogos superiores, los incisivos y primeros molares son los más simétricos en el brote. El primer diente permanente en emerger fue el incisivo central inferior o el primer molar inferior. Lo más frecuente fue que los caninos superiores e inferiores brotaran después que las primeras bicúspides.A cross-sectional, descriptive and epidemiologic study was conducted of the permanent dentition of children from Santa Clara municipality from 2005 to 2009 to determine the emergence order of permanent dentition. Universe included 45 724 infants of both sexes aged between 4 and 14. Sample included 1 769 subjects. There were emergence percentiles and from the 50 percentile the order was established. The teeth for each eruptive group were compared and symmetry was studied, establishing the emergence order. There were order differences between both sexes, hemiarcades and with the tables from other authors. The more symmetric teeth were the incisives and the first molars. We conclude that not always the lower teeth erupt before the upper ones, the incisives and first molars are the more symmetric in eruption. The first erupted permanent tooth may be the

  9. Surface electromyographic evaluation of jaw muscles in children with unilateral crossbite and lateral shift in the early mixed dentition. Sexual dimorphism.

    Science.gov (United States)

    Lenguas, Leticia; Alarcón, José-Antonio; Venancio, Filipa; Kassem, Marta; Martín, Conchita

    2012-11-01

    To examine the activity of jaw muscles at rest and during maximal voluntary clenching (MVC) in children with unilateral posterior crossbite (UPXB) and functional lateral shift in the early mixed dentition and to evaluate sex differences. The sample included 30 children (15 males, 15 females) aged 6 to 10 years old, with UPXB and functional mandibular lateral shift (≥1.5 mm) in the early mixed dentition. sEMG activity coming from the muscle areas (anterior temporalis [AT], posterior temporalis [PT], masseter [MA] and suprahyoid [SH]) were obtained from both the crossbite (XB) and noncrossbite (NONXB) sides at mandibular rest position. sEMG activity of the bilateral AT and MA muscles sides was obtained during MVC. Asymmetry and activity indexes were calculated for each muscle area at rest and during MVC; the MA/TA ratio during MVC was also determined. At rest, no differences were found between sexes for any muscle areas or asymmetry and activity indexes. No differences were found between XB and NONXB sides. During MVC, however, significant sex differences were found in AT and MA activity, with higher sEMG values in males than in females, on both XB and NONXB sides. Asymmetry indexes, activity indexes and MA/AT ratios did not show significant differences between the sexes. Activity was symmetric both in males and in females. At rest, no sex differences were found, but during MVC males showed higher activity than did females in both XB and NONXB AT and MA muscle areas. Muscular activity was symmetrical at rest and during MVC in both sexes. Sexual dimorphism should be considered in the diagnosis and treatment of UPXB and lateral shift in the early mixed dentition.

  10. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions.

    Science.gov (United States)

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-10-07

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the 'cone-in-cone' series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. © 2015 The Authors.

  11. Alveolar process fractures in the permanent dentition. Part 1. Etiology and clinical characteristics. A retrospective analysis of 299 cases involving 815 teeth

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Lauridsen, Eva

    2015-01-01

    process. RESULTS: Violence was the overall most frequent cause of injury in men (44%), whereas the three most common causes of this type of injury in women were violence (33%), falls (32%), or traffic injuries (26%). Fracture of the alveolar process occurred most frequently in the maxilla (74%) and less...... process fractures are rare. They occur most frequently in young males and are often associated with violence. Concomitant soft tissue injuries are frequent. This type of injury accordingly appears to result from a frontal impact transmitted through a soft tissue shield (the lips) where the zone of least......AIM: To describe the etiology and clinical characteristics of alveolar process fractures treated in a regional trauma clinic. MATERIAL AND METHOD: The study is a retrospective descriptive analysis of 299 patients (180 males, 119 females; 815 permanent teeth) diagnosed with fractures of the alveolar...

  12. Molariform mesiodens in primary dentition: a case report.

    Science.gov (United States)

    Indira, Md; Dhull, Kanika Singh; R, Sujatha; Kumar Ps, Praveen; Devi Bm, Gayatri

    2014-05-01

    A supernumerary tooth is a developmental anomaly and it has been argued to arise from multiple aetiologies. Mesiodens is a midline supernumerary tooth which is commonly seen in the maxillary arch, and incidence of molariform mesiodens in the maxillary midline is rare in permanent dentition and extremely uncommon in primary dentition. A midline supernumerary tooth in the primary dentition can cause an ectopic or a delayed eruption of permanent central incisors, which will further alter occlusion and may compromise aesthetics and formation of dentigerous cysts. This paper reports a rare case which had the presence of a molariform mesiodens in the primary dentition. The treatment plan consisted of extraction of the supernumerary tooth and regular observation of permanent central incisors for proper eruption and alignment.

  13. A transition space maintainer for the adolescent dentition: a case report.

    Science.gov (United States)

    Levine, N; Sigal, M J; Creighton, J M; Maeda, T

    1990-12-01

    Premature loss of teeth in posterior segments of the primary, mixed or permanent dentition may lead to space loss in an anterior-posterior dimension. This article illustrates how a simple, aesthetic and effective space maintainer can be used to prevent space loss in the permanent dentition.

  14. Enamel defects in decodious and permanent dentitions

    OpenAIRE

    Rosana Helena Schlittler Hoffmann

    2006-01-01

    Resumo: As mudanças ocorridas durante a formação do esmalte dental são marcadas permanentemente em sua estrutura e comumente se apresentam como opacidades demarcadas, opacidades difusas ou hipoplasias - de esmalte. - O desenvolvimento de defeitos de esmalte pode fornecer indícios de sua etiologia e isto pode ter implicações tanto clínicas quanto epidemiológicas. Desta forma, os objetivos desta dissertação apresentados na forma de dois artigos foram: 1 - Verificar a prevalência de hipoplasia, ...

  15. Gemination and Twinning in Permanent Dentition.

    Science.gov (United States)

    1981-09-11

    tooth, 15 linking tooth,16 synodonia17 and schizodontla,11 mirror image double tooth,18 fused teeth, 19 and geminated composite odontoma . 20...normal fashion, whereas, in an odontoma ,ameloblasts and odontoblasts lay down enamel and dentin in small rudimentary tooth-like structures during

  16. Triplication in permanent teeth: A rare case report

    Directory of Open Access Journals (Sweden)

    Nidhi Gera

    2017-01-01

    Full Text Available Fusion is an anomaly manifested in both deciduous and permanent dentitions. Triple tooth refers to the union of three separate tooth entities. It can involve the normal dentition or supernumerary teeth. Triplication is rarely encountered in deciduous and permanent dentition with an incidence of 0.02%. The case presented herein describes a rare case of triplication in permanent maxillary incisors and supernumerary teeth in a 15-year-old female.

  17. 青少年替牙期错(牙合)畸形的早期干预治疗%The early intervention treatment in mixed dentition malocclusions of adolescents

    Institute of Scientific and Technical Information of China (English)

    韩爽; 张晏更; 刘昕; 王岚

    2013-01-01

    目的 研究错(牙台)畸形的早期干预治疗对于青少年替牙期错(牙台)畸形的疗效.方法 选取错(牙合)畸形的流行病学调查过程中发现的替牙期错(牙合)畸形患者,进行早期干预治疗.结果 进行早期干预治疗的患者,均取得良好的疗效,有效地阻止了错(牙合)畸形的发展,或者延缓了发展趋势.结论 替牙期错(牙合)畸形的早期干预治疗,疗效明显.%Objective To study the effect of early intervention treatment of malocclusion deformity on adolescent dentition malocclusions.Methods Patients during the mixed dentition period of malocclusion deformity were selected according to the epidemiological investigation,and early intervention was performed.Results Patients with early treatment achieved good results-the development of malocclusion deformity was effectively blocked,or the development trend was retarded.Conclusion Early intervention in the treatment of mixed dentition malocclusions is effective and necessary.

  18. Space maintenance in the primary and mixed dentition.

    Science.gov (United States)

    Durward, C S

    2000-10-01

    The maintenance of arch length in the primary, mixed and early permanent dentition is important for the normal development of the occlusion. Premature loss of primary teeth can result in the loss of arch length leading to malocclusion. Space maintenance can often prevent space loss and either prevent the development of a later malocclusion or reduce its severity. The pattern of space loss depends on many factors including age, stage of development, which teeth have been lost, the presence of crowding or spacing, and occlusal relationships. Careful consideration of many factors is required when deciding whether space maintenance is indicated. Radiographs and space analysis can be helpful. Space maintainers can be fixed or removable. Band and loop space maintainers have fewer problems than other types. Frequent follow-ups to check for any problems following space maintainer insertion is recommended.

  19. Intrusive luxation of 60 permanent incisors

    DEFF Research Database (Denmark)

    Tsilingaridis, Georgios; Malmgren, Barbro; Andreasen, Jens O;

    2012-01-01

      Intrusive luxation in the permanent dentition is an uncommon injury but it is considered one of the most severe types of dental trauma because of the risk for damage to the periodontal ligament, pulp and alveolar bone. Management of intrusive luxation in the permanent dentition is controversial....... The purpose of this study was to evaluate pulp survival and periodontal healing in intrusive luxated permanent teeth in relation to treatment alternatives, degree of intrusion and root development....

  20. Changes in the Distribution of Periodontal Nerve Fibers during Dentition Transition in the Cat.

    Directory of Open Access Journals (Sweden)

    Koji Miki

    Full Text Available The periodontal ligament has a rich sensory nerve supply which originates from the trigeminal ganglion and trigeminal mesencephalic nucleus. Although various types of mechanoreceptors have been reported in the periodontal ligament, the Ruffini ending is an essential one. It is unknown whether the distribution of periodontal nerve fibers in deciduous teeth is identical to that in permanent teeth or not. Moreover, morphological changes in the distribution of periodontal nerve fibers during resorption of deciduous teeth and eruption of successional permanent teeth in diphyodont animals have not been reported in detail. Therefore, in this study, we examined changes in the distribution of periodontal nerve fibers in the cat during changes in dentition (i.e., deciduous, mixed and permanent dentition by immunohistochemistry of protein gene product 9.5. During deciduous dentition, periodontal nerve fibers were concentrated at the apical portion, and sparsely distributed in the periodontal ligament of deciduous molars. During mixed dentition, the periodontal nerve fibers of deciduous molars showed degenerative profiles during resorption. In permanent dentition, the periodontal nerve fibers of permanent premolars, the successors of deciduous molars, increased in number. Similar to permanent premolars, the periodontal nerve fibers of permanent molars, having no predecessors, increased in number, and were densely present in the apical portion. The present results indicate that the distribution of periodontal nerve fibers in deciduous dentition is almost identical to that in permanent dentition although the number of periodontal nerve fibers in deciduous dentition was low. The sparse distribution of periodontal nerve fibers in deciduous dentition agrees with clinical evidence that children are less sensitive to tooth stimulation than adults.

  1. Smoking and subsequent risk of early retirement due to permanent disability

    DEFF Research Database (Denmark)

    Husemoen, Lise Lotte N; Osler, Merete; Godtfredsen, Nina S

    2004-01-01

    on early retirement due to chronic disease. The objective of the study is to determine the effects of smoking behaviour on early retirement due to permanent disability in a large sample of the general population. METHODS: Follow-up study based on data from three longitudinal population studies conducted...... ratio of 5.66 (1.88-17.00) and 5.61 (2.11-14.92) in heavily smoking men and women, respectively, who were below age 60. CONCLUSIONS: Smokers are at considerably higher risk of early retirement due to chronic disease. In addition to the burden of disease, this leads to social and economic problems...

  2. Space maintenance in the primary and mixed dentitions.

    Science.gov (United States)

    Simon, Thomas; Nwabueze, Ifechide; Oueis, Hassan; Stenger, James

    2012-01-01

    Loss of space in the primary dentition is considered one of the main causes of malocclusion in the permanent dentition. The purpose of this paper is to review ond summarize the indications and use of space maintainers in primary and mixed dentitions as preventive measures of future malocclusion. Two main types of space maintainers are used to maintain the space in primary ond mixed dentitions: fixed and removable appliances. Band and loop is the appliance of choice when a primary maxillary or mandibular first molar is prematurely lost. With the premature loss of a second primary molar, Nance or transpalatal (TPA) appliances can be used on the maxillary arch and the lower lingual holding arch (LLHA) for the mandibular arch.

  3. Prevalência de oclusopatia na dentição decídua e permanente de crianças na cidade de São Paulo, Brasil, 1996 Malocclusion prevalence in the deciduous and permanent dentition of schoolchildren in the city of São Paulo, Brazil, 1996

    Directory of Open Access Journals (Sweden)

    Paulo Frazão

    2002-10-01

    Full Text Available O objetivo deste estudo foi estimar a prevalência de oclusopatia na dentição decídua e permanente de crianças de escolas públicas e privadas do Município de São Paulo, SP, Brasil, em 1996. A condição oclusal foi classificada em três categorias: normal, leve e moderada/severa conforme os critérios da Organização Mundial da Saúde. Os resultados referem-se a 985 exames em crianças de 5 e 12 anos de idade. A prevalência das oclusopatias foi alta, aumentando de 48,97 ± 4,53% na dentição decídua a 71,31 ± 3,95% na dentição permanente, sendo que a proporção de oclusopatia moderada/severa foi quase duas vezes maior na dentição permanente (OR = 1,87; IC95% = 1,43-2,45; p The purpose of this study was to estimate the prevalence of malocclusion in deciduous and permanent dentition of schoolchildren enrolled in public and private schools in the city of Sao Paulo, Brazil, in 1996. Occlusal conditions were classified as normal, mild, and moderate/severe according to World Health Organization criteria. The results refer to 985 schoolchildren ages five and 12 years. Prevalence of malocclusion was high, increasing from 48.97 ± 4.53% in the deciduous dentition to 71.31 ± 3.95% in the permanent dentition. The proportion of moderate/severe malocclusion was nearly twice as great in the second dentition (OR = 1.87; 95% CI = 1.43-2.45; p < 0.001. No significant difference was observed according to gender or public vs. private school. Statistically significant differences were associated with ethnicity, indicating the complexity and diversity of occlusion in the population and suggesting the need for longitudinal studies.

  4. Smoking and subsequent risk of early retirement due to permanent disability

    DEFF Research Database (Denmark)

    Husemoen, Lise Lotte N; Osler, Merete; Godtfredsen, Nina S;

    2004-01-01

    BACKGROUND: Smoking is the most important single preventable cause of a variety of common diseases, and a considerable share of premature death is attributable to smoking. Although the effects of smoking on morbidity and mortality are widely recognized, little is known about the impact of smoking...... on early retirement due to chronic disease. The objective of the study is to determine the effects of smoking behaviour on early retirement due to permanent disability in a large sample of the general population. METHODS: Follow-up study based on data from three longitudinal population studies conducted...

  5. The effect of preterm birth on the development of the dentition

    OpenAIRE

    Harila, V. (Virpi)

    2004-01-01

    Abstract The aim of this study was to examine the effect of preterm birth on the development of the dentition. The spesific aims were to examine the effect on deciduous and permanent tooth crown dimensions, the eruption of permanent teeth and the sagittal occlusal relationships within the dentition. The subjects consisted of 328 prematurely born (< 37 gestational weeks ) white and black children and 1804 control children, who participated in the cross-sectional study of the Collabor...

  6. Dental management of traumatic injuries to the primary dentition.

    Science.gov (United States)

    Dummett, C O

    2000-11-01

    There is considerable information on traumatic injury management of permanent teeth. However, there are no conclusive guidelines for treating traumatized primary teeth. This article will summarize a number of issues relative to primary dentition trauma and provide a system for treatment.

  7. Early postnatal development of the mandibular permanent first molar in infants with isolated cleft palate

    DEFF Research Database (Denmark)

    Hermann, Nuno V.; Zargham, Mostafa; Darvann, Tron Andre

    2012-01-01

    International Journal of Paediatric Dentistry 2012; 22: 280–285 Background. Based on measurements on dental casts, smaller permanent teeth in children with cleft palate have previously been reported in the literature; however, the early maturation of teeth and the size of the follicles and crowns...... have not been investigated. Hypothesis. The maturation of the mandibular permanent first molar (M1inf) is delayed, and the mesiodistal diameters of the follicle and crown of M1inf, respectively, are reduced in children with isolated cleft palate (ICP). Design. Retrospective, longitudinal. Cephalometric...... X‐rays were available for 2 and 22 months old children with clefts (64 children with ICP, and a control group of 38 children with unilateral incomplete cleft lip). The width of the follicle and the crown of M1inf, and the maturation of M1inf were assessed. Intra‐observer error was acceptable...

  8. Triple tooth in primary dentition: A proposed classification

    Directory of Open Access Journals (Sweden)

    Gaddam Shilpa

    2013-01-01

    Full Text Available Triple teeth may result from fusion, gemination or concrescence causing transient esthetic and functional problems in primary dentition and retardation or alteration of development and eruption of permanent successors. We report an unusual case of a boy aged five with fusion among maxillary left primary central incisor, lateral incisor and a supernumerary tooth concomitant with agenesis of permanent lateral incisor. A review of literature on triple tooth was done along with a proposed classification of the triple teeth.

  9. Dentigerous cyst in primary dentition: A case report

    Directory of Open Access Journals (Sweden)

    Passi S

    2008-01-01

    Full Text Available Dentigerous cyst is a developmental odontogenic cyst, which apparently develops by accumulation of fluid between the reduced enamel epithelium and the tooth crown of an unerupted tooth. There is usually no pain or discomfort associated with the cyst unless there is acute inflammatory exacerbation. Management of dentigerous cyst in primary dentition needs special consideration regarding the preservation of the developing permanent tooth buds. Here, we report a case of dentigerous cyst in primary dentition in a 10-year-old male patient and its management.

  10. Tooth wear patterns in the deciduous dentition.

    Science.gov (United States)

    Warren, John J; Yonezu, Takuro; Bishara, Samir E

    2002-12-01

    Tooth wear is common in the deciduous dentition. A recent study suggests that tooth wear in the deciduous dentition is related to subsequent tooth wear in adults, so that early identification of factors related to tooth wear could be of long-term benefit. The purposes of this study were to describe patterns of tooth wear in the deciduous dentition and to relate tooth wear to occlusal characteristics and longitudinal dietary patterns. Data were collected as part of a longitudinal study of a cohort of children recruited at birth from Iowa hospitals. Stone casts were obtained in the deciduous dentition stage, and 355 children, 4 to 5 years old, met the selection criteria. Tooth wear was categorized for each tooth as none, mild, moderate, or severe, and related to occlusal characteristics and longitudinal data on fruit juice and soft drink consumption. All children exhibited some tooth wear on at least 1 tooth, and nearly 16% of them had at least 1 tooth with severe wear. Tooth wear was generally more severe in the maxillary arch and the anterior teeth. Severe tooth wear on the molars was significantly related to posterior crossbites, but severe tooth wear on the incisors was related to Class III canine relationships. There were no statistically significant relationships between tooth wear and soft drink or fruit juice consumption. Based on our results, we concluded that mild tooth wear is universal in the deciduous dentition, but only a few occlusal factors are related to severe tooth wear. Tooth wear was not related to any dietary patterns we investigated.

  11. Research on orthodontic treatment for complete unilateral cleft lip and palate patients in late permanent dentition%恒牙晚期单侧完全性唇腭裂患者正畸治疗临床疗效研究

    Institute of Scientific and Technical Information of China (English)

    刘毅; 王春玲; 孙慧芳; 王海任

    2011-01-01

    Objective By measuring the post-surgery characteristics of complete unilateral cleft lip and palate (UCLP) patients' teeth, occlusion, soft and hard tissues in late permanent dentition, the purpose of this study was to investigate the clinical effects of orthodontic treatments for complete UCLP patients on face types, maxillary dental arch and occlusion relations and to provide reliable theoretic basis for treating these kinds of patients. Methods Ten post-surgery complete UCLP patients who had cleft lip and palate in late permanent dentition( From 15 to 17 years old) were selected in this research. Every patient was treated with maxillary slow arch expansion and fixed appliance. The related data about X-ray lateral skull films before therapy and after six months' maxillary expansion, as well as teeth models before expansion, after expansion and after six months' were measured. The Statistical Methods were paired t-test for dependent samples and two-way ANOVA, LSD-test were used for the mutual comparison between two groups. Results After orthodontic treatments, some measured data of soft and hard tissues in complete UCLP patients' lateral skull films had relatively significant changes (P <0.01 ). Arch width increased significantly in canine area and premolar area( P < 0. 01 ). The increase in premolar area could be maintained steadily (P < 0.05). Conclusions After orthodontic treatments, bone, soft and hard tissues and occlusion relations of complete UCLP patients in late permanent dentition who had get cleft lip and palate had relatively ideal effects.%目的 通过测量恒牙晚期单侧完全性唇腭裂(UCLP)患者术后牙(牙合)、软硬组织的相关数据,观察正畸治疗对患者面型、牙弓及咬合关系的临床疗效.方法 选择10例UCLP恒牙晚期(15~17岁)术后患者,采用上颌慢速扩弓联合固定矫治,对治疗前、扩弓保持半年后X线头颅侧位片及扩弓治疗前、扩弓结束后、保持半年后牙(牙合)

  12. Prevalência de defeitos de esmalte e sua relação com cárie dentária nas dentições decídua e permanente, Indaiatuba, São Paulo, Brasil Prevalence of enamel defects and the relationship to dental caries in deciduous and permanent dentition in Indaiatuba, São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Rosana H. Schlittler Hoffmann

    2007-02-01

    Full Text Available Os objetivos deste estudo foram verificar a prevalência de hipoplasia, opacidade demarcada e fluorose dentária em escolares nas dentições decídua e permanente e verificar a associação entre a presença desses defeitos de esmalte e a cárie dentária. A amostra foi de 624 pré-escolares de 5 anos e 309 escolares de 12 anos. A prevalência de cárie dentária foi avaliada por meio dos índices ceod e CPOD, e a prevalência dos defeitos de esmalte, com o índice DDE. A fluorose dentária foi medida pelos critérios do índice de Dean. O teste do qui-quadrado foi usado para verificar a associação e a razão de chances, analisando a força e a direção da associação. Aos cinco anos de idade, em crianças com experiência de cárie, houve associação positiva entre cárie dentária e defeitos de esmalte. Entretanto, na dentição permanente, apenas a hipoplasia e a opacidade demarcada foram associadas à cárie. Os resultados deste estudo indicaram maior chance de crianças virem a ter cárie, tanto na dentição decídua como na permanente, na presença de defeitos de esmalte, porém mais estudos são necessários para a comprovação dessa associação.The aim of this study was to determine the prevalence of hypoplasia, demarcated opacity and dental fluorosis among schoolchildren with deciduous and permanent dentition. The association between enamel defects and dental caries was also verified. The sample consisted of 624 schoolchildren aged 5 and 309 aged 12. The dmft and DMFT indexes were used to assess dental caries prevalence, DDE to assess enamel defects, and Dean to assess fluorosis. Chi-squared test was used to test significance (p < 0.05 and odds ratio to analyze prevalence of dental caries and enamel defects. A positive association between dental caries and enamel defects (hypoplasia, demarcated opacity and dental fluorosis was observed for schoolchildren aged 5. However, only hypoplasia and demarcated opacity were associated

  13. Occlusal Characteristics and Spacing in Primary Dentition: A Gender Comparative Cross-Sectional Study

    Science.gov (United States)

    Chandrasekhar, R.; Chandrappa, Vinay

    2014-01-01

    Context. Occlusion in primary teeth varies among children of different populations and races. Aim. To assess and compare the occlusal characteristics and spacing in primary dentition among 3–6-year-old Dravidian children. Materials and Methods. The study included 2281 school going children. The primary molar relation, canine relation, overjet, and overbite were assessed using Foster and Hamilton criteria. Spacing conditions were registered according to Kisling and Krebs criteria. Results. The flush terminal plane molar relation (80.3%) was the most common primary molar relation. The distal step molar relation was more frequently found in female children (12.8%) than in males (8.6%). Class 1 canine relation was the most prevalent canine relation (81.3%) among males and females. Ideal overjet (84.3%) and overbite (72.7%) were observed among the majority of the children. Spaced type of arches occurred more frequently than closed arches in this sample. The incidence of primate spaces was more in males than in females. Conclusion. The study population has fewer deviations from normal occlusion which indicates decreased tendency for malocclusion in permanent dentition. However, further longitudinal studies are necessary to identify the potential limitations of a clinical approach relying on early orthodontic diagnosis and intervention. PMID:27379294

  14. Análisis de la simetría del tamaño dentario mesiodistal de la misma muestra en dentición mixta y permanente: Estudio longitudinal Analysis of symmetry mesiodistal size teeth in mixed and permanent dentition in the same sample: A longitudinal study

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    M.D. Austro Martínez

    2004-12-01

    between the mesiodistal contact points of the crown, using a sharp-end gauge, with a 0,1 mm precision. All the measurements were made by the same viewer, directly to the mouth. For the statistic analysis was used the t Student test, with a level of statistic signification of p< 0,05. The main results include the symmetry of the mesiodistal size both in a mixed dentition and a permanent dentition, of the same sample.

  15. An in vitro study of the efficacy of mouthguard protection for dentoalveolar injuries in deciduous and mixed dentitions.

    Science.gov (United States)

    Johnston, T; Messer, L B

    1996-12-01

    Sports-related dental trauma remains a risk for children and adolescents. Although mouthguards provide protection, up to 25% of dentoalveolar injuries can occur with a mouthguard in place. This study examined the effect of mouthguard protection in an in vitro model. A total of 97 sheep mandibular segments with incisors at four developmental stages (early deciduous, ED, n = 37; middle deciduous, MD, n = 20; late deciduous, LD, n = 18; mixed dentition, PD, n = 22) was used. Customised pressure formed mouthguards (MG) provided protection from trauma produced by a servohydraulic materials testing machine to test incisors. Injuries were examined clinically, radiographically and by dissection. Mean forces required to produce dentoalveolar injury were significantly greater in test (with MG) teeth than control (no MG) teeth. Mean forces to produce injury in test teeth decreased with resorbing root lengths. Deciduous incisors differed in injury type: subluxations and horizontal root fractures predominated in test teeth; lateral luxations and horizontal root fractures in control teeth. Predominant injuries in test and control permanent incisors were enamel infractions and subluxations. The magnitude of lateral luxation measurements of individual teeth was reduced significantly by mouthguard protection in both deciduous and permanent dentitions. The mouthguard tended to increase the mobility of the teeth it encompassed and, in some instances, promoted dentoalveolar injury of adjacent teeth.

  16. The Optimal Dentition of the Periodontitis Patient

    DEFF Research Database (Denmark)

    Melsen, Birte; Laursen, Morten Godtfredsen

    2014-01-01

    This article focuses on the evolution of orthodontic treatment possibilities developed for degenerating dentitions in adult patients. Indications for such therapy comprise dentition suffering from an aggravation of a malocclusion, horizontal loss of periodontal tissue support, elongation and...

  17. Innovative chairside technique for the correction of ectopically erupting permanent first molar

    Directory of Open Access Journals (Sweden)

    Seema Thakur

    2012-01-01

    Full Text Available Introduction : Maxillary permanent first molars are frequently found ectopic teeth in mixed dentition. If left untreated, it may cause serious sequel including early loss of the primary second molar, space loss, and impaction of second premolars. Clinical Innovation: This article describes a new successful innovative method for the correction of ectopically erupting maxillary first permanent molar in an 8-year-old boy. Discussion: Early correction of ectopically erupting permanent molars is an integral part of interceptive orthodontics. Several treatment methods have been suggested. Among these, the interproximal wedging techniques are the simplest but are not always appropriate or feasible. The other treatment modalities may be either complicated, expensive, or require impression taking, appliance delivery, and activation appointments. The following case illustrates a new chairside technique that eliminates the need of impression taking, appliance delivery, and activation appointments and is very simple.

  18. Systematic review for orthodontic and orthopedic treatments for anterior open bite in the mixed dentition

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    Lucia Pisani

    2016-09-01

    Full Text Available Abstract Background The treatment options for the early treatment of anterior open bite are still controversial. The aim of this study was to evaluate the actual available evidence on treatments of anterior open bite in the mixed dentition in order to assess the effectiveness of the early treatment in reducing open bite, the most efficacious treatment strategy and the stability of the results. Materials and methods A literature survey was done on November 15, 2015, by means of appropriate Medical Subject Headings (MeSH using the following databases: PubMed, EMBASE, Cochrane Library, LILACS, VHL, and WEB OF SCIENCE. Randomized clinical trials and studies with a control group (treated or untreated were then selected by two authors. Trials including patients with syndromes or in the permanent dentition and studies concerning treatment with extractions, full-fixed appliances, or surgery were not considered. Full articles were retrieved for abstracts or titles that met the initial inclusion criteria or lacked sufficient detail for immediate exclusion. Results Two thousand five hundred sixty-nine studies about open bite were available; the search strategy selected 240 of them. Twenty-four articles have been judged suitably for the final review, and their relevant data were analyzed. Discussion Although this review confirms the effectiveness of early treatment of open bite, particularly when no-compliance strategies are employed, meta-analysis was unfeasible due to lack of standardization, important methodological limitations, and shortcomings of the studies. Conclusions A more robust approach to trial design in terms of methodology and error analysis is needed. Besides, more studies with longer periods of follow-up are required.

  19. Permanent human occupation of the central Tibetan Plateau in the early Holocene.

    Science.gov (United States)

    Meyer, M C; Aldenderfer, M S; Wang, Z; Hoffmann, D L; Dahl, J A; Degering, D; Haas, W R; Schlütz, F

    2017-01-06

    Current models of the peopling of the higher-elevation zones of the Tibetan Plateau postulate that permanent occupation could only have been facilitated by an agricultural lifeway at ~3.6 thousand calibrated carbon-14 years before present. Here we report a reanalysis of the chronology of the Chusang site, located on the central Tibetan Plateau at an elevation of ~4270 meters above sea level. The minimum age of the site is fixed at ~7.4 thousand years (thorium-230/uranium dating), with a maximum age between ~8.20 and 12.67 thousand calibrated carbon-14 years before present (carbon-14 assays). Travel cost modeling and archaeological data suggest that the site was part of an annual, permanent, preagricultural occupation of the central plateau. These findings challenge current models of the occupation of the Tibetan Plateau. Copyright © 2017, American Association for the Advancement of Science.

  20. Maturogenesis of an Early Erupted Immature Permanent Tooth: A Case Report With 7-Year Follow-Up.

    Science.gov (United States)

    Atabek, D; Sillelioğlu, H; Çinar, Ç; Ölmez, A

    2015-01-01

    The main objective of treatment of an undeveloped tooth (immature) is to provide vital pulp therapy to allow continued development of root dentin. A case report is presented that demonstrates the use of calcium hydroxide (CaOH₂) as an indirect pulp-copping material for the purpose of continued maturogenesis of an early-erupted permanent tooth with severe mobility and almost-begun root formation. Seven-year radiographic and clinical follow-up demonstrated a vital pulp and physiologic root development without any endodontic failure clinically or radiographicaly.

  1. Is permanent parasitism reversible?--critical evidence from early evolution of house dust mites.

    Science.gov (United States)

    Klimov, Pavel B; OConnor, Barry

    2013-05-01

    Long-term specialization may limit the ability of a species to respond to new environmental conditions and lead to a higher likelihood of extinction. For permanent parasites and other symbionts, the most intriguing question is whether these organisms can return to a free-living lifestyle and, thus, escape an evolutionary "dead end." This question is directly related to Dollo's law, which stipulates that a complex trait (such as being free living vs. parasitic) cannot re-evolve again in the same form. Here, we present conclusive evidence that house dust mites, a group of medically important free-living organisms, evolved from permanent parasites of warm-blooded vertebrates. A robust, multigene topology (315 taxa, 8942 nt), ancestral character state reconstruction, and a test for irreversible evolution (Dollo's law) demonstrate that house dust mites have abandoned a parasitic lifestyle, secondarily becoming free living, and then speciated in several habitats. Hence, as exemplified by this model system, highly specialized permanent parasites may drastically de-specialize to the extent of becoming free living and, thus escape from dead-end evolution. Our phylogenetic and historical ecological framework explains the limited cross-reactivity between allergens from the house dust mites and "storage" mites and the ability of the dust mites to inhibit host immune responses. It also provides insights into how ancestral features related to parasitism (frequent ancestral shifts to unrelated hosts, tolerance to lower humidity, and pre-existing enzymes targeting skin and keratinous materials) played a major role in reversal to the free-living state. We propose that parasitic ancestors of pyroglyphids shifted to nests of vertebrates. Later the nest-inhabiting pyroglyphids expanded into human dwellings to become a major source of allergens.

  2. Early permanent disappearance of abnormal muscle response during microvascular decompression for hemifacial spasm: a retrospective clinical study.

    Science.gov (United States)

    Jiang, Chengrong; Xu, Wu; Dai, Yuxiang; Lu, Tianyu; Jin, Wei; Liang, Weibang

    2016-12-15

    The objective of this study is to explore the cause of early abnormal muscle response (AMR) disappearance during microvascular decompression for hemifacial spasm and the clinical outcomes of these patients. Three hundred seventy-two patients received microvascular decompression (MVD) under intraoperative electrophysiological monitoring in Nanjing Drum Tower Hospital in 2014; the characteristic AMR of HFS was observed in 359 patients during the operation. And the 359 patients were divided into two groups based on whether AMR had remained before the beginning of the decompression procedure for offending vessels. Thirty-three patients who showed a permanent disappearance of AMR before the beginning of decompression were regarded as group I. Dural opening and the succeeding CSF drainage produced a permanent disappearance of AMR in 13. During the dissection of lateral cerebellomedullary cistern, a permanent disappearance of AMR was found in 20 patients. Thirty-two patients were cured immediately; delayed resolution (7 days after surgery) was found in one patient. No complications were observed and no recurrence was found during the follow-up period in the 33 patients. In the other 326 patients (group II), AMR disappeared temporarily before the beginning of the decompression procedure for offending vessels in 42 patients. After decompression, AMR disappeared completely in 305 patients. Two hundred sixty-seven patients were cured immediately and 57 patients got a delayed resolution (2 days to 45 weeks after surgery). The two left did not get a complete abolition of spasm. Three cases of hearing loss, one hoarseness, and nine delayed facial paralysis were observed. The reason of early abnormal muscle response disappearance may be that the degree of neurovascular compression was not serious; these patients were more likely to get an immediate cure. Continuous intraoperative electrophysiological monitoring of AMR is necessary.

  3. Sequelae of Trauma to Primary Dentition

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    Cíntia ZEMBRUSKI-JABER

    2006-08-01

    Full Text Available Objective: The aim of this study was to determine the presence of clinical and radiographic signs of injury to the maxillary primary incisors and the children carers' knowledge about dental trauma ocurrence in a 45 children group from three to eight years old. Method: Before the clinical examination, the carers were asked about their children's dental trauma events. After that, took course the maxillary incisors clinical and radiographical examination, excluding the ones with caries, fillings, or pulpar treatments. Results: Discoloration (50.0% was the most common present sign of trauma followed by avulsion (17.6% and the pulp canal obliteration (56.3% was the major result of the radiographical signal. Boys had more trauma recorded than girls and the maxillary central incisors were the most vulnerable to injury. Besides, the amount of trauma recorded by clinical and radiographic examination was bigger than that reported in the questionnaire by mothers or children carers. Conclusion: The results related in this study reinforce the need of immediate attention to trauma on deciduous dentition and long term observation of the developing permanent successor.

  4. [Diagnosis of orodentomaxillary disease in students with mixed dentition in the city of Toluca].

    Science.gov (United States)

    Sánchez Flores, I; Rincón Mejía, V M; Gómez Salas, L; Kubodera Ito, T

    1989-09-01

    A study was undertaken on 1,474 school children of either sex, aged six to 12, from the community of Toluca, Mexico State, selected by dual-stage conglomerate sampling, both from rural and urban areas. Data registered included teeth with caries, lost teeth and filled cavities for permanent dentition, and teeth with caries, extracted or obturated teeth in the case of primary dentition. Periodontal health status was evaluated according to World Health Organization criteria, and conditions of occlusion were graded according to Angle's classification.

  5. Erupted maxillary conical mesiodens in deciduous dentition in a Bengali girl - A case report

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    Ray Debjit

    2005-09-01

    Full Text Available Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch. It is the most significant dental anomaly affecting permanent dentition mainly and primary dentition rarely. It may occur as an isolated dental anomalous condition or may be associated with a syndrome. Many theories have been promulgated to explain its etiology. But an exact etiology is still obscure. Incidence of mesiodens in children varies from 0.15 to 3.8%. Boys are affected more (2 : 1 than Girls. Morphologically, mesiodens may be of three types: the most commonly seen is conical, while tuberculate and supplementary types.

  6. Erupted maxillary conical mesiodens in deciduous dentition in a Bengali girl--a case report.

    Science.gov (United States)

    Ray, Debjit; Bhattacharya, B; Sarkar, S; Das, G

    2005-09-01

    Mesiodens is a midline supernumerary tooth commonly seen in the maxillary arch. It is the most significant dental anomaly affecting permanent dentition mainly and primary dentition rarely. It may occur as an isolated dental anomalous condition or may be associated with a syndrome. Many theories have been promulgated to explain its etiology. But an exact etiology is still obscure. Incidence of mesiodens in children varies from 0.15 to 3.8%. Boys are affected more (2:1) than girls. Morphologically, mesiodens may be of three types: the most commonly seen is conical, while tuberculate and supplementary types.

  7. Early orthopedic correction of skeletal Class III malocclusion using combined reverse twin block and face mask therapy

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    Vinay Kumar Chugh

    2015-01-01

    Full Text Available A 6-year 8-month-old girl presented with a moderate Class III malocclusion characterized by mid-face deficiency and an anterior cross bite. In the first phase, the patient was treated with combination of reverse twin block and facemask therapy. In phase two, fixed appliances were placed in the permanent dentition. The post treatment results were good and a favorable growth tendency could be observed. The correction of the Class III malocclusion occurred by a combination of skeletal and dental improvements. This report shows successful correction of skeletal Class III malocclusion in the early transitional dentition using combination therapy.

  8. Early orthopedic correction of skeletal Class III malocclusion using combined reverse twin block and face mask therapy.

    Science.gov (United States)

    Chugh, Vinay Kumar; Tandon, Pradeep; Prasad, Veerendra; Chugh, Ankita

    2015-01-01

    A 6-year 8-month-old girl presented with a moderate Class III malocclusion characterized by mid-face deficiency and an anterior cross bite. In the first phase, the patient was treated with combination of reverse twin block and facemask therapy. In phase two, fixed appliances were placed in the permanent dentition. The post treatment results were good and a favorable growth tendency could be observed. The correction of the Class III malocclusion occurred by a combination of skeletal and dental improvements. This report shows successful correction of skeletal Class III malocclusion in the early transitional dentition using combination therapy.

  9. Validity of moyers mixed dentition analysis for Saudi population.

    Science.gov (United States)

    Al-Dlaigan, Yousef H; Alqahtani, Nasser D; Almoammar, Khalid; Al-Jewair, Thikriat; Salamah, Fahad Bin; Alswilem, Mohamme; Albarakati, Sahar F

    2015-01-01

    To evaluate the applicability of Moyers probability tables and to formulate more accurate mixed dentition prediction tables in the Saudi population. A cross-sectional study was conducted at the College of Dentistry, Kind Saud University, Saudi Arabia. The data were collected from 410 (203 males and 207 females) orthodontic study models, which had erupted mandibular permanent incisors, maxillary, mandibular canines and premolars. The mesiodistal widths were measured using a digital caliper with an accuracy of 0.01 mm. Student's paired t-test was used to compare the mean width values derived from this study with the values derived using the Moyers table. Simple linear regression was used to evaluate the linear relationship between the combined mesiodistal widths of the mandibular permanent incisors and the canine-premolar segments in each dental arch. The regression equations for the maxillary canine-premolar segment (males: Y=10.27+0.48X; females: Y=11.71 + 0.39X) and the mandibular canine-premolar segment (males: Y=9.71 + 0.40X; females: 11.28 + 0.39X) were used to formulate new probability tables on the Moyers pattern. Statistically significant differences were observed between predicted widths in our subjects and the widths obtained using Moyers tables. The new prediction tables derived in this study provided a more precise mixed dentition space analysis than Moyers prediction tables in estimating tooth dimensions in the Saudi population.

  10. Clinical audit of children with permanent tooth injuries treated at a dental hospital in Ireland.

    LENUS (Irish Health Repository)

    Stewart, C

    2011-02-01

    To audit key demographic and clinical factors relating to treatment of trauma to the permanent dentition at the Paediatric Dental Department, Cork University Dental School and Hospital, Ireland and to compare clinical management with guideline recommendations.

  11. Several early interventions for ectopic maxillary canines.

    Directory of Open Access Journals (Sweden)

    Carlos Astorga

    2012-07-01

    Full Text Available Maxillary canine impactation is often encountered in orthodontic clinical practice and the aetiology is associated to genetic factors as well as local space factors. If preventive treatment is not started in ectopic maxillary canines, some possible consequences may occur, such as resorption of the roots of the neighboring permanent teeth, cysts, ankylosis and expensive surgical and orthodontic treatment. The aim of this review was to preset several early treatment modalities for ectopic maxillary canines based on recent scientific evidence. Four are the most important: Only extractions intervention, extraction of deciduous canines with cervical pull headgear, active intervention in late mixed dentition and active intervention in early mixed dentition. These different modalities showed a greater increasing the rate of normal eruption of ectopic canines ( 80-97%. The extraction of primary canine alone is still an effective method to prevent canine impactation, whose success rate would be increased if some other method interceptive is added.

  12. Comparison of two non-radiographic techniques of mixed dentition space analysis and evaluation of their reliability for Bengali population

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    Barun Dasgupta

    2012-01-01

    Full Text Available Context: Mixed dentition arch analysis system is an important criterion in determining the type of orthodontic treatment plan. Different mixed dentition arch analysis system are available and among them both Moyer′s and Tanaka-Jhonson method of space analysis was developed for North American children. Anthropological study reveals that tooth size varies among different ethnicities The present study was performed to determine the reliability of Moyer′s and Tanaka-Jhonson′s method of mixed dentition arch analysis system among Bengali population. Aims: To perform the comparative evaluation of the two mixed dentition space analysis system among Bengali population. Materials and Methods: Dental casts of maxillary and mandibular arches of 70 Bengali children with permanent dentitions were fabricated. The mesiodistal crown dimensions of all erupted permanent incisors, canines, and premolars were measured with digital callipers. For particular sum of mandibular incisors, Moyer′s and Tanaka-Jhonson′s mixed dentition arch analysis were calculated and further statistical analysis was carried on. Statistical analysis used: Descriptive statistics including the mean, standard deviation, and minimum and maximum values, unpaired′t′ tests, correlation coefficient "r" were calculated and tabulated. Results: Tanaka and Johnston regression equations under-estimated the mesiodistal widths of permanent canines and premolars. On the other hand, there were no statistically significant differences between actual mesiodistal widths of canines and premolars and the predicted widths from Moyers charts at the 50% level for the lower and upper arches, among Bengali population. Conclusions: The study suggested that both Moyer′s and Tanaka-Jhonson′s mixed dentition arch analysis are applicable in Bengali population but with little modification in their regression equation.

  13. Thallium isotope evidence for a permanent increase in marine organic carbon export in the early Eocene

    Science.gov (United States)

    Nielsen, S.G.; Mar-Gerrison, S.; Gannoun, A.; LaRowe, D.; Klemm, V.; Halliday, A.N.; Burton, K.W.; Hein, J.R.

    2009-01-01

    The first high resolution thallium (Tl) isotope records in two ferromanganese crusts (Fe-Mn crusts), CD29 and D11 from the Pacific Ocean are presented. The crusts record pronounced but systematic changes in 205Tl/203Tl that are unlikely to reflect diagenetic overprinting or changes in isotope fractionation between seawater and Fe-Mn crusts. It appears more likely that the Fe-Mn crusts track the Tl isotope composition of seawater over time. The present-day oceanic residence time of Tl is estimated to be about 20,000??yr, such that the isotopic composition should reflect ocean-wide events. New and published Os isotope data are used to construct age models for these crusts that are consistent with each other and significantly different from previous age models. Application of these age models reveals that the Tl isotope composition of seawater changed systematically between ~ 55??Ma and ~ 45??Ma. Using a simple box model it is shown that the present day Tl isotope composition of seawater depends almost exclusively on the ratio between the two principal output fluxes of marine Tl. These fluxes are the rate of removal of Tl from seawater via scavenging by authigenic Fe-Mn oxyhydroxide precipitation and the uptake rate of Tl during low temperature alteration of oceanic crust. It is highly unlikely that the latter has changed greatly. Therefore, assuming that the marine Tl budget has also not changed significantly during the Cenozoic, the low 205Tl/203Tl during the Paleocene is best explained by a more than four-fold higher sequestration of Tl by Fe-Mn oxyhydroxides compared with at the present day. The calculated Cenozoic Tl isotopic seawater curve displays a striking similarity to that of S, providing evidence that both systems may have responded to the same change in the marine environment. A plausible explanation is a marked and permanent increase in organic carbon export from ~ 55??Ma to ~ 45??Ma, which led to higher pyrite burial rates and a significantly reduced

  14. Avaliação cefalométrica dos efeitos do aparelho Herbst no tratamento da deficiência mandibular na dentadura permanente Cephalometric evaluation of the effect of the Herbst appliance in the treatment of the mandibular retrognathism in the permanent dentition

    Directory of Open Access Journals (Sweden)

    OmarGabriel da Silva Filho

    2007-12-01

    Full Text Available OBJETIVO: o objetivo do presente estudo cefalométrico retrospectivo consistiu em investigar os efeitos induzidos pelo aparelho Herbst, complementados pela mecânica ortodôntica com aparelho Straight wire e elásticos de Classe II, na correção da má oclusão Classe II, divisão 1, Padrão II, com deficiência mandibular, na dentadura permanente. METODOLOGIA: foram traçadas telerradiografias iniciais (idade média de 12 anos e 10 meses e finais (idade média de 14 anos e 8 meses de 18 pacientes, 12 meninos e 6 meninas, para quantificar o comportamento de 12 grandezas cefalométricas representativas da posição sagital das bases apicais, convexidade facial, rotação mandibular e posição sagital dos incisivos superiores e inferiores. O tempo médio de tratamento foi de 22,5 meses, sendo 9,8 meses com o aparelho Herbst e 13 meses com a mecânica ortodôntica subseqüente. RESULTADOS E CONCLUSÕES: os resultados registraram: 1 ausência de influência no comportamento da maxila; 2 avanço mandibular; 3 redução na convexidade facial; 4 preservação da inclinação do plano mandibular e 5 presença de compensação dentária, sobretudo nos incisivos inferiores (vestibularização. Reitera-se, portanto, o fato de que, mesmo com aparelho ortopédico fixo, é mais previsível e mais fácil obter compensação dentária do que remodelação esquelética na correção ortopédica da deficiência mandibular.AIM: The purpose of the current cephalometric study was to investigate the effects induced by the Herbst appliance followed by fixed orthodontic Straight wire mechanics and Class I elastics to correct a Class II division 1 malocclusion with a mandibular deficiency in the permanent dentition. MATERIAL AND METHODS: Initial (mean age of 12 years and 10 months and final (mean age of 14 years and 8 months cephalometric radiographs of 12 boys and 6 girls were traced to measure 12 cephalometric measurements that represented the sagittal position of

  15. Tropical cyclones and permanent El Niño in the early Pliocene epoch.

    Science.gov (United States)

    Fedorov, Alexey V; Brierley, Christopher M; Emanuel, Kerry

    2010-02-25

    Tropical cyclones (also known as hurricanes and typhoons) are now believed to be an important component of the Earth's climate system. In particular, by vigorously mixing the upper ocean, they can affect the ocean's heat uptake, poleward heat transport, and hence global temperatures. Changes in the distribution and frequency of tropical cyclones could therefore become an important element of the climate response to global warming. A potential analogue to modern greenhouse conditions, the climate of the early Pliocene epoch (approximately 5 to 3 million years ago) can provide important clues to this response. Here we describe a positive feedback between hurricanes and the upper-ocean circulation in the tropical Pacific Ocean that may have been essential for maintaining warm, El Niño-like conditions during the early Pliocene. This feedback is based on the ability of hurricanes to warm water parcels that travel towards the Equator at shallow depths and then resurface in the eastern equatorial Pacific as part of the ocean's wind-driven circulation. In the present climate, very few hurricane tracks intersect the parcel trajectories; consequently, there is little heat exchange between waters at such depths and the surface. More frequent and/or stronger hurricanes in the central Pacific imply greater heating of the parcels, warmer temperatures in the eastern equatorial Pacific, warmer tropics and, in turn, even more hurricanes. Using a downscaling hurricane model, we show dramatic shifts in the tropical cyclone distribution for the early Pliocene that favour this feedback. Further calculations with a coupled climate model support our conclusions. The proposed feedback should be relevant to past equable climates and potentially to contemporary climate change.

  16. What dentition assures oral function?

    DEFF Research Database (Denmark)

    Gotfredsen, Klaus; Walls, Angus W G

    2007-01-01

    groups, social classes, cultures, regions and countries. For most people, occlusal support and stability are obtained with three to four functional posterior units with a symmetrical pattern of tooth loss or five to six units with an asymmetrical pattern. There was no relationship between occlusal......OBJECTIVE: To evaluate the relationship between dentition and oral function. MATERIAL AND METHODS: A search of the English literature was undertaken using PubMed and appropriate keywords. Citations were identified and hand sorted to confirm their validity against our inclusion criteria. Four...... specific areas of oral function were addressed; (I) masticatory function, (II) aesthetics, satisfaction and psychosocial ability, (III) occlusal support and stability and (IV) other functionality including tactile perception, phonetics and taste. RESULTS: From an initial pool of 1460 citations, 83 articles...

  17. Treatment of nonsyndromic dentigerous cysts in primary dentition

    Directory of Open Access Journals (Sweden)

    Mehmet Cemal Akay

    2011-02-01

    Full Text Available Mehmet Cemal Akay, Erdem Kaya, Mert ZeytinoğluFaculty of Dentistry, Department of Oral and Maxillofacial Surgery, Ege University, Bornova, Izmir, TurkeyObjective: Dentigerous cysts are benign odontogenic cysts that are associated with the crowns of permanent teeth. They usually occur singly and are located in the mandible. Nonsyndromic bilateral dentigerous cysts (NSBDC are rarely seen during childhood. The aim of this study was to determine the long-term effects of the marsupialization technique in growing children with NSBDC.Study design: Seven patients with NSBDC (4 female, 3 male ranging in age from 7 to 9 years (mean 8.35 years were involved in the study. All the individuals were treated by marsupialization. Space-maintaining appliances were applied during permanent teeth eruption. Intraoral photographs, and panoramic and periapical films were taken before surgery and during healing.Results: The NSBDC were successfully treated by the marsupialization technique and rapid healing period was observed in the growing patients, without any loss of permanent teeth. No recurrence was seen in the long-term follow-up period (3–10 years.Conclusion: Our clinical and radiological results revealed that using the marsupialization technique in children with NSBDC provided safe healing of permanent teeth around the dentigerous cysts in a short period. However, treatment planning and regular clinical follow-ups are necessary to ensure clinical success.Keywords: nonsyndromic bilateral dentigerous cysts, primary dentition, marsupialization

  18. Timetable for oral prevention in childhood--developing dentition and oral habits: a current opinion.

    Science.gov (United States)

    Majorana, Alessandra; Bardellini, Elena; Amadori, Francesca; Conti, Giulio; Polimeni, Antonella

    2015-01-01

    As most of the etiologic factors of malocclusion are of genetic origin and thus cannot be prevented, environmental causative factors have become the focus for correction. Early interception of oral habits may be an important step in order to prevent occlusal disturbances in children. The identification of an abnormal habit and the assessment of its potential immediate and long-term effects on the dentition and potentially on the craniofacial complex should be made at an early stage. This paper focuses on the most common oral habits influencing dentofacial growth in childhood and management of these habits in the developing dentition.

  19. Regional odontodysplasia in the primary dentition associated with eruption failure

    Directory of Open Access Journals (Sweden)

    Santanu Mukhopadhyay

    2016-01-01

    Full Text Available Regional odontodysplasia (RO is an uncommon nonhereditary developmental anomaly of dental hard tissues derived from ectoderm and mesoderm. The condition is more common in females, may affect primary and permanent dentitions with the maxilla, involves twice as frequently as mandible. The exact etiology of RO is unknown. Diagnosis is usually made by clinical and radiographic findings, sometimes supplemented with histopathologic examination. Clinically, teeth are hypoplastic with surface pits and grooves, and have brownish or yellowish discoloration. On the radiograph, there is reduced radiodensity of enamel and dentin with a lack of contrast between them. In this article, we described a case of a 3½-year-old girl with RO. The left maxillary quadrant was affected. The patient also showed eruption failure. Treatment of RO is, to a great extent, individualized. As the condition was asymptomatic, the present case was managed conservatively.

  20. Força de mordida em crianças com mantenedor de espaço funcional na fase da dentadura mista inicial Bite force in children with functional space maintainer in early mixed dentition

    Directory of Open Access Journals (Sweden)

    Suzane Rodrigues Jacinto-Gonçalves

    2009-08-01

    Full Text Available OBJETIVO: verificar a influência do mantenedor de espaço funcional (MEF na força muscular em crianças com perda prematura de molares decíduos na fase inicial da dentadura mista (5,5 a 6,5 anos de idade com oclusão normal, considerando-se o padrão facial. MÉTODOS: a amostra foi constituída por dois grupos: Grupo MEF (n = 15, com perda precoce de pelo menos um molar decíduo; e Grupo Controle (n = 16. Determinou-se a força de mordida máxima (FM com um tubo transmissor pressurizado, conectado a um circuito eletrônico analógico/digital antes (t0, um mês (t1 e 6 meses (t6 após a instalação do mantenedor. O padrão facial foi determinado pelo índice de Jarabak (FHR. Os dados foram analisados pela estatística descritiva, análise de variância para medidas repetidas, teste t e correlação de Pearson. RESULTADOS:a FM foi significativamente menor em t0 e t1 para o Grupo MEF em relação ao Controle. Em t6 não houve diferença. Os dois grupos apresentaram a FM significativamente maior em t6, em relação a t0, mas o percentual de variação para o Grupo MEF foi significativamente maior. Os valores de FHR não se correlacionaram com a FM, não ocorrendo diferença entre os tipos faciais intragrupos. Os dolicofaciais do Grupo MEF apresentaram a FM significativamente menor que os do Grupo Controle, em t0 e t1, mas não em t6. CONCLUSÃO: o maior aumento na FM para o Grupo MEF após 6 meses foi favorecido pelo maior número de contatos oclusais, devido aos dentes artificiais, melhorando a função e recuperando a força muscular.AIM: To verify the influence of a functional space maintainer (FSM in muscle strength in children with premature loss of primary molars in early mixed dentition (5.5-6.5 years old with normal occlusion, considering the facial pattern. METHODS: The sample was distributed in: FSM Group (n = 15, with premature loss of at least one primary molar and a Control Group (n = 16. It was determined the maximal bite force (BF

  1. Risk of developing palatally displaced canines in patients with early detectable dental anomalies: a retrospective cohort study

    Science.gov (United States)

    GARIB, Daniela Gamba; LANCIA, Melissa; KATO, Renata Mayumi; OLIVEIRA, Thais Marchini; NEVES, Lucimara Teixeira das

    2016-01-01

    ABSTRACT The early recognition of risk factors for the occurrence of palatally displaced canines (PDC) can increase the possibility of impaction prevention. Objective To estimate the risk of PDC occurrence in children with dental anomalies identified early during mixed dentition. Material and Methods The sample comprised 730 longitudinal orthodontic records from children (448 females and 282 males) with an initial mean age of 8.3 years (SD=1.36). The dental anomaly group (DA) included 263 records of patients with at least one dental anomaly identified in the initial or middle mixed dentition. The non-dental anomaly group (NDA) was composed of 467 records of patients with no dental anomalies. The occurrence of PDC in both groups was diagnosed using panoramic and periapical radiographs taken in the late mixed dentition or early permanent dentition. The prevalence of PDC in patients with and without early diagnosed dental anomalies was compared using the chi-square test (p<0.01), relative risk assessments (RR), and positive and negative predictive values (PPV and NPV). Results PDC frequency was 16.35% and 6.2% in DA and NDA groups, respectively. A statistically significant difference was observed between groups (p<0.01), with greater risk of PDC development in the DA group (RR=2.63). The PPV and NPV was 16% and 93%, respectively. Small maxillary lateral incisors, deciduous molar infraocclusion, and mandibular second premolar distoangulation were associated with PDC. Conclusion Children with dental anomalies diagnosed during early mixed dentition have an approximately two and a half fold increased risk of developing PDC during late mixed dentition compared with children without dental anomalies. PMID:28076458

  2. Mosaic Convergence of Rodent Dentitions

    Science.gov (United States)

    Lazzari, Vincent; Charles, Cyril; Tafforeau, Paul; Vianey-Liaud, Monique; Aguilar, Jean-Pierre; Jaeger, Jean-Jacques; Michaux, Jacques; Viriot, Laurent

    2008-01-01

    Background Understanding mechanisms responsible for changes in tooth morphology in the course of evolution is an area of investigation common to both paleontology and developmental biology. Detailed analyses of molar tooth crown shape have shown frequent homoplasia in mammalian evolution, which requires accurate investigation of the evolutionary pathways provided by the fossil record. The necessity of preservation of an effective occlusion has been hypothesized to functionally constrain crown morphological changes and to also facilitate convergent evolution. The Muroidea superfamily constitutes a relevant model for the study of molar crown diversification because it encompasses one third of the extant mammalian biodiversity. Methodology/Principal Findings Combined microwear and 3D-topographic analyses performed on fossil and extant muroid molars allow for a first quantification of the relationships between changes in crown morphology and functionality of occlusion. Based on an abundant fossil record and on a well resolved phylogeny, our results show that the most derived functional condition associates longitudinal chewing and non interlocking of cusps. This condition has been reached at least 7 times within muroids via two main types of evolutionary pathways each respecting functional continuity. In the first type, the flattening of tooth crown which induces the removal of cusp interlocking occurs before the rotation of the chewing movement. In the second type however, flattening is subsequent to rotation of the chewing movement which can be associated with certain changes in cusp morphology. Conclusion/Significance The reverse orders of the changes involved in these different pathways reveal a mosaic evolution of mammalian dentition in which direction of chewing and crown shape seem to be partly decoupled. Either can change in respect to strong functional constraints affecting occlusion which thereby limit the number of the possible pathways. Because convergent

  3. Mosaic convergence of rodent dentitions.

    Directory of Open Access Journals (Sweden)

    Vincent Lazzari

    Full Text Available BACKGROUND: Understanding mechanisms responsible for changes in tooth morphology in the course of evolution is an area of investigation common to both paleontology and developmental biology. Detailed analyses of molar tooth crown shape have shown frequent homoplasia in mammalian evolution, which requires accurate investigation of the evolutionary pathways provided by the fossil record. The necessity of preservation of an effective occlusion has been hypothesized to functionally constrain crown morphological changes and to also facilitate convergent evolution. The Muroidea superfamily constitutes a relevant model for the study of molar crown diversification because it encompasses one third of the extant mammalian biodiversity. METHODOLOGY/PRINCIPAL FINDINGS: Combined microwear and 3D-topographic analyses performed on fossil and extant muroid molars allow for a first quantification of the relationships between changes in crown morphology and functionality of occlusion. Based on an abundant fossil record and on a well resolved phylogeny, our results show that the most derived functional condition associates longitudinal chewing and non interlocking of cusps. This condition has been reached at least 7 times within muroids via two main types of evolutionary pathways each respecting functional continuity. In the first type, the flattening of tooth crown which induces the removal of cusp interlocking occurs before the rotation of the chewing movement. In the second type however, flattening is subsequent to rotation of the chewing movement which can be associated with certain changes in cusp morphology. CONCLUSION/SIGNIFICANCE: The reverse orders of the changes involved in these different pathways reveal a mosaic evolution of mammalian dentition in which direction of chewing and crown shape seem to be partly decoupled. Either can change in respect to strong functional constraints affecting occlusion which thereby limit the number of the possible

  4. Associations between fluorosis of permanent incisors and fluoride intake from infant formula, other dietary sources and dentifrice during early childhood

    Science.gov (United States)

    Levy, Steven M.; Broffitt, Barbara; Marshall, Teresa A.; Eichenberger-Gilmore, Julie M.; Warren, John J.

    2017-01-01

    Objectives The authors describe associations between dental fluorosis and fluoride intakes, with an emphasis on intake from fluoride in infant formula. Methods The authors administered periodic questionnaires to parents to assess early fluoride intake sources from beverages, selected foods, dentifrice and supplements. They assessed relationships between fluorosis of the permanent maxillary incisors and fluoride intake from beverages and other sources, both for individual time points and cumulatively using area-under-the-curve (AUC) estimates. The authors determined effects associated with fluoride in reconstituted powdered infant formulas, along with risks associated with intake of fluoride from dentifrice and other sources. Results Considering only fluoride intake from age 3 to 9 months, the authors found that participants with fluorosis (97 percent of which was mild) had significantly greater cumulative fluoride intake (AUC) from reconstituted powdered infant formula, other beverages with added water or a combination of these than did those without fluorosis. For participants aged 16 to 36 months, participants with fluorosis had significantly higher fluoride intake from water by itself, dentifrice or a combination of these than did those without fluorosis. In a model combining both the 3- to 9-month and 16- to 36-months age groups, the significant variables were fluoride intake from reconstituted powder concentrate formula (by participants aged 3–9 months), other beverages with added water (also by participants aged 3–9 months) and dentifrice (by participants aged 16–36 months). Conclusions Greater fluoride intakes from reconstituted powdered formulas (when participants were aged 3–9 months) and other water-added beverages (when participants were aged 3–9 months) increased fluorosis risk as did higher dentifrice intake by participants when aged 16 to 36 months. Clinical Implications Results suggest that prevalence of mild dental fluorosis could be

  5. Light-force technique for the early treatment of an ectopic tooth.

    Science.gov (United States)

    Cozzani, Mauro; Lupini, Daniela; Siciliani, Giuseppe

    2005-01-01

    Free crown tipping can be useful when teeth do not erupt in their physiologic sequence and a real intraosseous migration and eruption of a single tooth into a distant ectopic position can be observed. This article presents a case of an ectopic mandibular lateral incisor treated early, with the light-force technique and uncontrolled forces, and finished with the bidimensional edgewise appliance. A Caucasian female patient, 10 years 10 months of age, had a mandibular left lateral incisor displacement, with the lateral incisor crown positioned mesial to left second primary molar. An early treatment was planned to correct the mandibular left lateral incisor displacement and to allow proper eruption of the mandibular left canine and first premolar. A second phase of treatment, in permanent dentition, was planned for the dental Class II subdivision on the right and deep bite correction. Phase 1 treatment was completed after 10 months; phase 2 treatment was initiated in the permanent dentition and lasted 18 months. Treatment achieved the following outcomes: (1) mandibular lateral incisor in corrected position; (2) full canine and molar Class I relationship; (3) overjet and overbite within the normal limits; (4) symmetric arches; and (5) a balanced profile. The radiograph evaluation revealed good root parallelism and mandibular left lateral incisor light root resorption. The light-force technique is not only a possible alternative but the ideal appliance for treatment in the mixed dentition, when the permanent teeth should be controlled.

  6. Management of a child with severe hypodontia in the mixed dentition stage of development.

    Science.gov (United States)

    Tong, H J; Tahmassebi, J F

    2014-12-01

    Severe hypodontia is a condition characterized by developmental absence of six or more teeth and affects 0.14-0.3% of the overall population. Hypodontia can have a marked psychosocial effect and functional implications for a growing child. A 10-year-old girl with a medical history of hypothyroidism and repaired spinal bifida was referred to the Leeds Dental Institute as she was becoming increasingly concerned about her appearance. On clinical examination, the patient had severe wear of her over-retained maxillary primary central incisors, microdontia of mandibular anterior teeth (32, 34, 41, 42, 43), and loss of anterior vertical dimension. Radiographic examination revealed that the patient had 11 missing permanent teeth (14, 13, 12, 11, 21, 22, 23, 24, 31, 35, 44), an ectopic mandibular left canine and taurodontism of the permanent molars. Management of the patient included an intensive preventive programme with placement of fissure sealants; scaling of calculus deposition on microdont teeth; composite resin reconstruction of microdont teeth; fabrication of removable partial overdentures tailored aesthetically to match the patient's age; orthodontic consultation and monitoring for the eruption of ectopic canine and permanent dentition. The patient and her parents reported marked improvement in self-esteem following dental treatment. After 2 years of follow-up, a new pair of dentures were made and designed to allow ease of eruption of the existing permanent dentition. All permanent teeth have erupted. The patient is ready for further assessment and planning for future orthodontic and restorative/implant treatment. This case illustrates the essential role of the paediatric dentist in the management of hypodontia in the mixed dentition stage.

  7. Zirconia-Prefabricated Crowns for Pediatric Patients With Primary Dentition: Technique and Cementation for Esthetic Outcomes.

    Science.gov (United States)

    Cohn, Carla

    2016-09-01

    Traditionally, many clinicians tend to forego esthetic considerations when full-coverage restorations are indicated for pediatric patients with primary dentitions. However, the availability of new zirconia pediatric crowns and reliable techniques for cementation makes esthetic outcomes practical and consistent when restoring primary dentition. Two cases are described: a 3-year-old boy who presented with severe early childhood caries affecting both anterior and posterior teeth, and a 6-year-old boy who presented with extensive caries of his primary posterior dentition, including a molar requiring full coverage. The parents of both boys were concerned about esthetics, and the extent of decay indicated the need for full-coverage restorations. This led to the boys receiving treatment using a restorative procedure in which the carious teeth were prepared for and restored with esthetic tooth-colored zirconia crowns. In both cases, comfortable function and pleasing esthetics were achieved.

  8. Hexa Helix: Modified Quad Helix Appliance to Correct Anterior and Posterior Crossbites in Mixed Dentition

    Directory of Open Access Journals (Sweden)

    Syed Mohammed Yaseen

    2012-01-01

    Full Text Available Among the commonly encountered dental irregularities which constitute developing malocclusion is the crossbite. During primary and mixed dentition phase, the crossbite is seen very often and if left untreated during these phases then a simple problem may be transformed into a more complex problem. Different techniques have been used to correct anterior and posterior crossbites in mixed dentition. This case report describes the use of hexa helix, a modified version of quad helix for the management of anterior crossbite and bilateral posterior crossbite in early mixed dentition. Correction was achieved within 15 weeks with no damage to the tooth or the marginal periodontal tissue. The procedure is a simple and effective method for treating anterior and bilateral posterior crossbites simultaneously.

  9. Occlusal Characteristics of the Primary Dentition Revisited.

    Science.gov (United States)

    Alexander, Stanley A; Askari, Marjan; Lewis, Patricia

    2015-11-01

    The occlusal characteristics of the primary dentition of 130 children 3 to 6 years old were examined. Variables were the terminal plane relationship, primary canine occlusion, spacing, overjet and overbite relationships. The flush terminal plane was the most common finding. A Class I relationship of the primary canine occurred in 85% of the subjects. Spaced dentitions occurred 81% of the time, while the presence of primate spaces occurred in at least one of the four quadrants. The overjet relationship varied from +1 mm to 4 mm in all subjects, and the majority of children were considered to have a normal overbite.

  10. SECONDARY RETENTION OF PERMANENT MOLARS - A REPORT OF 5 FAMILIES

    NARCIS (Netherlands)

    RAGHOEBAR, GM; TENKATE, LP; HAZENBERG, CAM; BOERING, G; VISSINK, A

    1992-01-01

    The aetiopathogenesis of secondary retention is not fully understood, but heredity is involved in at least some cases. In this study first-degree relatives of 52 patients with secondary retention of permanent molars were screened for the presence of the same phenomenon in their dentition. Familial o

  11. VERTICAL CONTROL OF OVERBITE IN MIXED DENTITION BY TRAINER SYSTEM

    Directory of Open Access Journals (Sweden)

    Miroslava Dinkova

    2014-11-01

    Full Text Available Purpose. The purpose of this study is to follow-up the biometrical and skeletal vertical changes in patients with deep overbite in mixed dentition after a functional orthodontic treatment with Trainer System™ is conducted. Material and Methods. 32 patients (20 girls and 12 boys with deep overbite in mixed dentition were followed-up. An orthodontic treatment with Trainer System™, including Trainer for kids (T4K-blue, T4K-red and Myobrace was conducted. The recommended time for wearing the appliances was 8–12 hours, mostly at the night and 1–2 hours total time during the day. All the patients were photo-documented. Impressions, panoramic radiographs and lateral cephalograms were taken before the beginning of the treatment and at the end of every single step in relation with every change of appliances. Comparative biometrical and cephalometric analyses were made. The data was statistically processed. Results. The comparative biometrical analyses showed reduction of overbite with 2.5–3.5 mm after the end of the orthodontic treatment. 62% of cases showed relapse from 0.5 to 1mm. After the end of the orthodontic treatment an inclination of upper and lower incisors and changes with M/SN, М/F, ANB, SNA, SNB values were established. Conclusions. If untreated during the growing period, deep overbite leads to serious functional disorders, pathologic abrasion and myo-articular problems. Myofunctional Trainer System™ is successfully applied in the management of deep overbite in growing kids with early mixed dentition. The design of appliances helps the right positioning of tongue and jaws, removes bad habits, harmonizes tooth arches, corrects the vertical problems.

  12. Sonic Hedgehog Signaling and Development of the Dentition

    Directory of Open Access Journals (Sweden)

    Maisa Seppala

    2017-05-01

    Full Text Available Sonic hedgehog (Shh is an essential signaling peptide required for normal embryonic development. It represents a highly-conserved marker of odontogenesis amongst the toothed vertebrates. Signal transduction is involved in early specification of the tooth-forming epithelium in the oral cavity, and, ultimately, in defining tooth number within the established dentition. Shh also promotes the morphogenetic movement of epithelial cells in the early tooth bud, and influences cell cycle regulation, morphogenesis, and differentiation in the tooth germ. More recently, Shh has been identified as a stem cell regulator in the continuously erupting incisors of mice. Here, we review contemporary data relating to the role of Shh in odontogenesis, focusing on tooth development in mammals and cartilaginous fishes. We also describe the multiple actions of this signaling protein at the cellular level.

  13. Gender influence on occlusal characteristics in the primary dentition

    Directory of Open Access Journals (Sweden)

    Nisha Rani Yadav

    2014-01-01

    Full Text Available Objectives: The objective of this study was to assess and discuss the influence of gender on occlusal characteristics of primary dentition. Materials and Methods: In this study, cluster randomized sampling was done to select 4-6-year-old children from Government primary schools of Farukh Nagar block, Gurgaon, Haryana, India. Children were evaluated clinically for occlusal characteristics of primary dentition such as molar relation, Canine relation, overjet, overbite, openbite, scissors bite, and crossbite. Chi-square test was used to compare the occlusal characteristics of both genders. Results: Flush terminal plane, Class I Canine relation and both primate as well as developmental spaces were found to be prevalent in the study population, in percentages of 62.4%, 67.2%, and 37.6%, respectively. It was observed that females had more spacing, distal step molar relation and increased overjet as compared to males. Males had more Class II Canine relation, crowding, openbite, overbite, and incompetent lips as compared to females. Significant differences were found between males and females w.r.t various occlusal characteristics. Conclusion: Most of the children had gender influence on malocclusion, which indicates the need for early interception or correction of malocclusion traits based on the gender of the child.

  14. Caries experience in the primary dentition and presence of plaque in 7-year-old Chinese children: A 4-year time-lag study

    NARCIS (Netherlands)

    Hu, X.; Fan, M.; Mulder, J.; Frencken, J.E.F.M.

    2015-01-01

    OBJECTIVES: The aim of the present study was to test the hypothesis that dental caries prevalence and caries experience in primary dentitions has increased over 4 years and to compare the presence of plaque on permanent teeth in child cohorts over 4 years. MATERIALS AND METHODS: A time-lag study des

  15. Treatment Effect of Class Ⅱ Malocclusion in Early Permanent Dentition with Jasper Jumper Appliance%Jasper Jumper矫治器治疗恒牙(牙合)期骨性Ⅱ类错(牙合)的疗效观察

    Institute of Scientific and Technical Information of China (English)

    黄臻; 伍军; 郑莹; 桑婷

    2010-01-01

    目的 探讨Jasper Jumper矫治器治疗恒牙(牙合)期骨性Ⅱ类错(牙合)的临床疗效.方法 对13例恒牙(牙合)期骨性Ⅱ类错(牙合)病人应用Jasper Jumper矫治器治疗.通过治疗前后的头影测量对比,分析其疗效.结果 13例病人戴用Jasper Jumper矫治器5~7个月后,下颌均明显前移,下颌后缩面型显著改善.SNB角增大了1.9°;前牙覆盖减小了4.6 mm,其中骨性变化占43.5%;牙性变化占56.5%;磨牙关系改善了4.4 mm,其中骨性占45.5%,牙性变化占54.5%.治疗后Olp-Pg、Ii-OLp、Mi-OLp、覆盖、磨牙关系及SNB角、ANB角与治疗前比较差异均有统计学意义(均P<0.05).结论 Jasper Jumper矫治器能有效的治疗骨性Ⅱ类错(牙合).

  16. [Cross-sectional study of the evolution of the primary dentition: shape of dental arches, overjet and overbite].

    Science.gov (United States)

    de Castro, Liana Amado; Modesto, Adriana; Vianna, Roberto; Soviero, Vera Lígia Mendes

    2002-01-01

    The aim of this study was to evaluate the characteristics (shape of dental arches, overjet and overbite) of the primary dentition of 6- to 39-month-old children from four nurseries of Rio de Janeiro, Brazil, and to associate them to gender and dentition phase. It was observed that 68.6% of the children presented round upper arch, while 31.4% had triangular upper arch; 92% of the children presented U-shaped lower arch and 8% had square-shaped lower arch. Moderate overjet was observed in 38.3% of the children, and slight overjet, in 30.3%. Severe (26.6%) and negative (25.5%) overbites were the most prevalent modalities of that condition. There was no association between gender and the studied characteristics. There was statistically significant association between the dentition phase and the shape of the arch, overjet and overbite (p < 0.001, chi-square test). It was possible to observe, in the present study, that early signs of malocclusions appeared when first primary molars erupted, as the posterior vertical dimension of occlusion increased. It was, thus, verified that early signs of malocclusions appear as the primary dentition develops. It is very important that the first dental visit occur during the first year of age, since it allows the pediatric dentist to prevent or carry out an early diagnosis of malocclusions in the primary dentition.

  17. The prevalence and distribution of dental caries in four early medieval non-adult populations of different socioeconomic status from Central Europe.

    Science.gov (United States)

    Stránská, Petra; Velemínský, Petr; Poláček, Lumír

    2015-01-01

    The aim of the study was to map the dental health status in non-adult individuals and to verify whether and how the existence of caries in the non-adult age group is associated with the different socio-economic status of early medieval populations. We studied the dental remains from the acropolis of the Mikulčice settlement agglomeration, where members of the higher social classes were buried, and from the Mikulčice hinterland. Overall, we evaluated 2544 teeth/3714 alveoli of deciduous dentition and 1938 teeth/2128 alveoli of permanent dentition. We determined the number of individuals with dental caries (i.e., caries frequency index, F-CE) and the proportion of teeth/alveoli with caries/ante-mortem tooth loss (i.e., caries intensity index, I-CE). We found no statistical significant difference in the F-CE values between the Mikulčice hinterland and the acropolis. In addition, we found no statistically significant difference in the proportion of teeth with carious lesions (I-CE) either in the case of deciduous dentition or in the case of permanent dentition between the hinterland and the acropolis. In the case of permanent dentition, the statistically significant highest proportion of carious lesions (I-CE) was found in Mikulčice I (p ≤ 0.05). We confirmed an increase in the rate of caries with age. The level of caries at all of the studied medieval locations was very low. We presume that lifestyle and the associated dietary habits and hygienic practices of the individuals or population groups had a greater influence on dental caries than did the socio-economic status of these individuals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Methods of orthopedic treatment of dentition defects

    Directory of Open Access Journals (Sweden)

    Konnov V.V.

    2016-09-01

    Full Text Available The article is devoted to the methods of orthopedic treatment of dentition defects. To restore the functionality and individual aesthetic standards of dental system, with different types of partial loss of teeth, depending on the anatomical and topographical conditions, various kinds of dental prosthesis designs are used in the oral cavity: non-removable (bridges, cantilever, adhesive dentures and removable (laminar and clasp dental prostheses, as well as their combinations.

  19. Impact of Early Intervention on Expressive and Receptive Language Development among Young Children with Permanent Hearing Loss

    Science.gov (United States)

    Meinzen-Derr, Jareen; Wiley, Susan; Choo, Daniel I.

    2011-01-01

    Along with early detection, early intervention (EI) is critical for children identified with hearing loss. Evidence indicates that many children with sensorineural hearing loss experience improved language abilities if EI services were initiated at an "early" age. The present study's objectives were to determine the impact of a state EI program on…

  20. Impact of Early Intervention on Expressive and Receptive Language Development among Young Children with Permanent Hearing Loss

    Science.gov (United States)

    Meinzen-Derr, Jareen; Wiley, Susan; Choo, Daniel I.

    2011-01-01

    Along with early detection, early intervention (EI) is critical for children identified with hearing loss. Evidence indicates that many children with sensorineural hearing loss experience improved language abilities if EI services were initiated at an "early" age. The present study's objectives were to determine the impact of a state EI program on…

  1. Localized idiopathic root resorption in the primary dentition: Review of the literature and a case report.

    Science.gov (United States)

    Nasehi, Atefeh; Mazhari, Fatemeh; Mohtasham, Nooshin

    2015-01-01

    Idiopathic root resorption (IRR) is an infrequent condition that is usually found as an accidental finding on radiography. A significant number of cases of IRR in permanent dentition have been presented but are rarely reported in primary dentition. The aim of this case report is to present a case of localized IRR in a 7-year-old boy. The patient was referred because of increased mobility of the left mandibular primary second molar. On radiographic evaluation, severe root resorption of that tooth, and mild root resorption of the right mandibular primary second molar were evident; the patient was caries-free. The left affected tooth was lost, and after placing a band and loop space maintainer, the patient was followed for 18 months. A patient with an abnormal pattern of root resorption, especially in the primary dentition, should alert the clinician to rule out the known important local and systemic factors. The exact causes of and treatments for IRR continue to be discovered.

  2. Evaluation of mixed dentition analyses in north Indian population: A comparative study

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    Ravi Kumar Goyal

    2014-01-01

    Full Text Available Introduction: Mixed dentition regression equations analyses (Moyers, Tanaka-Johnston are based on European population , reliability of these methods is questionable over other population. Materials and Methods: The present study was conducted on total 260 study models. This study was done in two phases. In the first phase, linear regression equations were made. In the second phase, comparison of actual values of sum of mesiodistal width of canine, first and second premolars with the predicted values proposed by Moyers, Tanaka-Johnston, and the new proposed mixed dentition analysis for North Indian population were made. Results: Set of four linear regression equations for predicting sum of mesiodistal width of permanent canine, first premolar and second premolar in North Indian population from sum of mesiodistal width of mandibular incisors and mandibular first molars, were proposed as ; (a for males, maxillary arch, Y = 2.9 + 0.40X, (b mandibular arch Y = 3.91 + 0.37X (c for females, maxillary arch Y = 0.56 + 0.45X (d mandibular arch Y = 1.14 + 0.42X. Moyers and Tanaka-Johnston, mixed dentition analysis , is found to be overestimating the mesiodistal width of unerupted canine and premolars in North Indian population.

  3. Evaluation of Moyer's mixed dentition space analysis in Indian children

    Science.gov (United States)

    Baheti, Kamalshikha; Babaji, Prashant; Ali, Meer J.; Surana, Ashish; Mishra, Samvit; Srivastava, Madhulika

    2016-01-01

    Aim and Objectives: Tooth size prediction values are not universal for all ethnic and racial groups. The present study evaluated the applicability of Moyer's mixed dentition space analysis in the Marwari community of Rajasthan, India. Materials and Methods: The mesiodistal dimension of permanent mandibular incisors, maxillary and mandibular canine, and premolars of both sides were measured and averaged in 200 adolescents (100 males and 100 females) of the Marwari population in Rajasthan using digital Vernier caliper. Data were statistically analyzed using Student's t–test. The data were then compared with Moyer's predicted values. The tooth measurements of male and female participants were compared with unpaired t-test. Results: Moyer's prediction chart was not comparable with the study population group. The coefficient of correlation and coefficient of determination in our study was 0.57 and 0.25, respectively. Mesiodistal width of measured teeth was lesser in females compared to males for both canine and premolars (P = 0.471 and P = 0.0001, respectively). Conclusion: There was significant statistical difference between values of the present study and Moyer's prediction values. Hence, new regression equation and prediction table can be used to predict mesiodistal dimensions of canine and premolars in Marwari children of Rajasthan. PMID:27891312

  4. Traumatic injuries to permanent teeth in Turkish children, Ankara.

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    Altun, Ceyhan; Ozen, Buğra; Esenlik, Elçin; Guven, Günseli; Gürbüz, Taşkin; Acikel, Cengizhan; Basak, Feridun; Akbulut, Erman

    2009-06-01

    The aim of this study was to identify the types and etiologies of dento-alveolar injuries among patients who were treated for injuries to maxillary and/or mandibular permanent teeth at the Gulhane Medical Academy, Department of Pediatric Dentistry, Center of Dental Sciences in Ankara, Turkey to provide a basis for determining optimal treatment approaches and educational needs. From a total of 4956 children aged 6-12 years (mean age: 8.91 +/- 1.95) applying to the Center, 472 children (9.5%) were found to have suffered dental injuries during a period of 2 years. Injuries were classified according to drawings and texts based on the WHO classification system, as modified by Andreasen and Andreasen. Injury rates were highest among children age 6 and ages 8-10. The most frequently injured permanent teeth were the maxillary central incisors (88.2%), and the maxillary right central permanent incisor made up 47.2% of all injured teeth. The most common cause of dental trauma was falling while walking or running (40.3%). Most injuries involved a single tooth (64.8%). The most common type of injury was enamel fracture (44.6%). There was a significant difference in gender, where boys more often suffered from a dental hard tissue and pulp injury than girls (P = 0.019), whereas there was no difference in gender (P = 0.248) in the distribution of periodontal injuries. Injuries were found to occur more frequently during the summer (P trauma, preventive orthodontic treatment in early mixed dentition may play an important role in reducing traumatic dental injuries.

  5. Evaluation of Moyers mixed dentition analysis in school children

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    Durgekar Sujala

    2009-01-01

    Full Text Available Background and Objective: The purpose of this study is to test the reliability of Moyers mixed dentition analysis in school children. Materials and Methods: A study was conducted on a sample of 150 school children within the age group of 13 to 16 years old who had all permanent teeth that were fully erupted. Dental impressions were taken with alginate impression material and immediately poured with dental stone. Mesiodistal dimensions of permanent mandibular incisors, maxillary and mandibular canines, and premolars were measured using a digital caliper with a resolution of 0.01 mm. Statistical Analysis: The coefficient of correlation (r was calculated to find the correlation between the sums of the canine, premolars in both arches, and mandibular incisors. A Student′s unpaired t test was calculated to compare the tooth dimension between male and female subjects. The actual measurements were compared with the predicted values obtained with the Moyers prediction tables at the 35 th , 50 th , and 75 th percentile confidence levels. A Student′s t test was calculated to compare the actual and predicted values. Using this data, linear regression equations were formulated for tooth size prediction. The coefficient of determination [r2] was calculated to find the accuracy of the formulated prediction equations. The standard error of estimate (SEE was calculated to determine the validity of the proposed equations. Results: Moyers prediction tables are not an accurate method to estimate tooth dimension in our samples. The mesiodistal crown dimension in the buccal segment of the mandibular arch was larger in males (p=0.04 than in females. Conclusion: The differences noted between predicted values from the Moyers tables and that of the present investigation is the result of racial and ethnic diversity. The accuracy of the prediction equation should be tested in a larger sample.

  6. Evaluation of Moyers mixed dentition analysis in school children.

    Science.gov (United States)

    Durgekar, Sujala Ganapati; Naik, Vijay

    2009-01-01

    The purpose of this study is to test the reliability of Moyers mixed dentition analysis in school children. A study was conducted on a sample of 150 school children within the age group of 13 to 16 years old who had all permanent teeth that were fully erupted. Dental impressions were taken with alginate impression material and immediately poured with dental stone. Mesiodistal dimensions of permanent mandibular incisors, maxillary and mandibular canines, and premolars were measured using a digital caliper with a resolution of 0.01 mm. The coefficient of correlation (r) was calculated to find the correlation between the sums of the canine, premolars in both arches, and mandibular incisors. A Student's unpaired t test was calculated to compare the tooth dimension between male and female subjects. The actual measurements were compared with the predicted values obtained with the Moyers prediction tables at the 35 th , 50 th , and 75 th percentile confidence levels. A Student's t test was calculated to compare the actual and predicted values. Using this data, linear regression equations were formulated for tooth size prediction. The coefficient of determination [r2] was calculated to find the accuracy of the formulated prediction equations. The standard error of estimate (SEE) was calculated to determine the validity of the proposed equations. Moyers prediction tables are not an accurate method to estimate tooth dimension in our samples. The mesiodistal crown dimension in the buccal segment of the mandibular arch was larger in males (p=0.04) than in females. The differences noted between predicted values from the Moyers tables and that of the present investigation is the result of racial and ethnic diversity. The accuracy of the prediction equation should be tested in a larger sample.

  7. Permanent 125I-seed prostate brachytherapy: early prostate specific antigen value as a predictor of PSA bounce occurrence

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    Mazeron Renaud

    2012-03-01

    Full Text Available Abstract Purpose To evaluate predictive factors for PSA bounce after 125I permanent seed prostate brachytherapy and identify criteria that distinguish between benign bounces and biochemical relapses. Materials and methods Men treated with exclusive permanent 125I seed brachytherapy from November 1999, with at least a 36 months follow-up were included. Bounce was defined as an increase ≥ 0.2 ng/ml above the nadir, followed by a spontaneous return to the nadir. Biochemical failure (BF was defined using the criteria of the Phoenix conference: nadir +2 ng/ml. Results 198 men were included. After a median follow-up of 63.9 months, 21 patients experienced a BF, and 35.9% had at least one bounce which occurred after a median period of 17 months after implantation (4-50. Bounce amplitude was 0.6 ng/ml (0.2-5.1, and duration was 13.6 months (4.0-44.9. In 12.5%, bounce magnitude exceeded the threshold defining BF. Age at the time of treatment and high PSA level assessed at 6 weeks were significantly correlated with bounce but not with BF. Bounce patients had a higher BF free survival than the others (100% versus 92%, p = 0,007. In case of PSA increase, PSA doubling time and velocity were not significantly different between bounce and BF patients. Bounces occurred significantly earlier than relapses and than nadir + 0.2 ng/ml in BF patients (17 vs 27.8 months, p Conclusion High PSA value assessed 6 weeks after brachytherapy and young age were significantly associated to a higher risk of bounces but not to BF. Long delays between brachytherapy and PSA increase are more indicative of BF.

  8. Simplified management of anterior worn dentition

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    Haroon Rashid

    2013-01-01

    Full Text Available Tooth wear has started to affect a greater number of younger people. Its precautions, symptoms, and treatment modalities therefore have to be well understood. This case study presents a patient with severe tooth wear that had led to displeasing esthetics. Surgical crown lengthening and composite restorations were performed after the provision of a stabilizing splint. This helped to improve the esthetics considerably leaving the patient satisfied. The aim of this case study is to portray an approach to how even a patient with severe tooth wear can have access to an esthetically pleasing dentition.

  9. Impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    Science.gov (United States)

    Chen, Zhe (Jay); Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-01-01

    Previous studies have shown that the procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations depends strongly on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al. (Int. J. Radiat. Oncol. Biol. Phys. 41, 1069–1077–1998) was used to characterize the edema evolutions observed previously during clinical PIB for prostate cancer. The concept of biologically effective dose (BED), taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not taken into account appropriately, can increase the cell survival and decrease the probability of local control of PIB. The edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life for radioactive decay and decreasing energy of the photons energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days

  10. The impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    Science.gov (United States)

    (Jay Chen, Zhe; Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-08-01

    Previous studies have shown that procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations strongly depends on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al (1998 Int. J. Radiat. Oncol. Biol. Phys. 41 1069-77) was used to characterize the edema evolutions previously observed during clinical PIB for prostate cancer. The concept of biologically effective dose, taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not appropriately taken into account, can increase the cell survival and decrease the probability of local control of PIB. The magnitude of an edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life of radioactive decay and decreasing photon energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days) is longer than

  11. Odontomas in the primary dentition: literature review and case report.

    Science.gov (United States)

    Sheehy, Evelyn C; Odell, Edward W; Al-Jaddir, Ghaida

    2004-01-01

    Odontomas are hamartomatous developmental malformations of dental tissues. They are very rarely diagnosed in the primary dentition. The purpose of this paper was to review the literature in relation to odontomas in the primary dentition, and describe the dental management of a child, age 4 years and 8 months, who had a complex odontoma.

  12. Oral Care for Developmentally Disabled Children: The Primary Dentition Stage.

    Science.gov (United States)

    Kenny, David J.; Judd, Peter L.

    1988-01-01

    Developmental disabilities and chronic illness can impact the oral health of children in the preeruptive and primary dentition stages. The article covers prevention and management of dental caries; gingival changes; trauma to the primary dentition; sucking, swallowing, and mastication; extraorally fed patients; and factitial injuries. Home-care…

  13. The dating and interpretation of Chusang indicates permanent human occupation of the interior of the Tibetan Plateau in the early Holocene

    Science.gov (United States)

    Meyer, Michael; Aldenderfer, Mark; Wang, Zhijun; Hoffmann, Dirk; Dahl, Jenny; Degering, Detlev; Haas, Randy; Schlütz, Frank; Gliganic, Luke; May, Jan-Hendrik

    2017-04-01

    central plateau. We suggest that migration onto the plateau during the early Holocene was enabled by the wetter regional climate at that time. These findings challenge (i) current models of the occupation of the Tibetan Plateau and (ii) the original dating of Chusang that - based on OSL multi-grain dating - suggests and an age for the imprints of ca. 20 ka. 1. Aldenderfer, M. (2011): Peopling the Tibetan plateau: Insights from archaeology. High Alt. Med. Biol. 12, 141-147. 2. Chen, F. H. et al. (2015): Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 B.P. Science 347, 248-250. 3. Meyer, M.C. et al. (2017): Permanent human occupation of the central Tibetan Plateau in the early Holocene. Science 355, 64-67. 4. Lu, D. et al. (2016): Ancestral Origins and Genetic History of Tibetan Highlanders. The American Journal of Human Genetics 99, 580-594. 5. Xiang, K. et al. (2013): Identification of a Tibetan-specific mutation in the hypoxic gene EGLN1 and its contribution to high-altitude adaptation. Molecular biology and evolution 30, 1889-1898.

  14. Newborn hearing screening in the Campania region (Italy): early language and perceptual outcomes of infants with permanent hearing loss.

    Science.gov (United States)

    Marciano, E; Laria, C; Malesci, R; Iadicicco, P; Landolfi, E; Niri, C; Papa, C; Franzè, A; Auletta, G

    2013-12-01

    Hearing loss in children causes a deficit in early perceptive and language skills. The objective of this study was to evaluate early receptive and expressive language outcomes in children with hearing loss, identified by hearing screening, compared to the time of diagnosis. We studied 18 severely hearing impaired children who were divided into two groups according to the time of diagnosis. Evaluation of communicative language ability was carried out at 18 month of age using the "MacArthur Child Development Inventory" questionnaire, while evaluation of acoustic-perceptual abilities was assessed with the Genovese-Arslan protocol every three months following diagnosis. The linguistic communicative and acoustic-perceptual outcomes of hearing impaired children diagnosed before 6 months of age followed those expected for normally hearing children, with a trend of temporal progression of skills that were faster than those of children diagnosed after 6 months of age.

  15. Odontometric sex estimation in humans using measurements on permanent canines. A comparison of an early Neolithic and an early medieval assemblage from Germany.

    Science.gov (United States)

    Flohr, Stefan; Kierdorf, Uwe; Kierdorf, Horst

    This study analyzed whether cervical canine dimensions measured at the enamel-cement junction can provide a basis for sex estimation in human skeletal remains and whether discriminant functions developed for one assemblage can be successfully applied also to others. Cervical canine dimensions were recorded for an Early Neolithic (Linear Pottery Culture) and an early medieval skeletal assemblage from Germany. Only individuals in whom sex estimation based on standard diagnostic criteria could be performed with a high degree of certainty were included. Sexual dimorphism in cervical canine dimensions was higher in the early medieval assemblage. Values in females of the Early Neolithic assemblage exceeded those of the early medieval assemblage, while there were no significant differences in males. Discriminant analysis led to a maximum correct classification of sex (cross validation results) of 94.0% in the early medieval and of 79.2% in the Early Neolithic assemblage. Applying the discriminant functions developed on one assemblage to the other led to poor classification results. Cervical canine dimensions are highly correlated with sexually dimorphic skeletal traits and may provide a good basis for sexing archaeological individuals. It is suggested that due to population differences in canine dimensions, either assemblage specific discriminant functions should be developed or the applicability of existing formulae obtained on other assemblages to the assemblage under study should be carefully checked.

  16. Caries Diagnosis in the Mixed Dentition Using ICDAS II

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    Erica Simone dos Santos Souza

    2015-10-01

    Full Text Available Objective: To assess the dental caries prevalence with ICDAS II in the mixed dentition, 40 children aged 7 to 11 years old, participating in a social program, whose parents and/or guardians signed a informed consent form. Material and Methods: Clinical examination was carried out after brushing. A single researcher performed the examination and the diagnosis consistency was obtained by Kappa coefficient in 12% of the sample. All dental surfaces were examined receiving a two-digit code. The first one refers to the presence of restoration/sealant and the second, the severity of carious lesions. The data was processed at SPSS software version 10.0 and analyzed using descriptive statistics (absolute distribution, percentage, mean and standard deviation. Results: The coefficient intra-examiner agreement was 0,83. Caries prevalence was considered high because 100% of the children had some surface with non-cavitated caries lesion. ICDAS II can be easily transformed to dmf-s or DMF-S without compromising its integrity. For dmf-s/DMF-S decayed surfaces were considered ICDAS codes 3 to 6, resulting in a dmf-s = 6,57 where 11 children (27,5% presented no decayed deciduous teeth surface. DMF-S = 2,0 showed that 15 children (37,5% had none decayed permanent surface, determining a underestimation of the caries disease when using dmf-d/dmf-s and DMF-S indexes. Conclusion: A careful viewing of initial caries lesions makes ICDAS II usefull in evaluating the health promotion actions impact, supporting the planning process, implementation and evaluation of program activities.

  17. Early functional, esthetic, and psychological rehabilitation of preschool child with nonsyndromic oligodontia and anodontia in mixed dentition stage through conservative systematic approach: A case report with 5-year follow-up

    Science.gov (United States)

    Rathee, Manu; Malik, Poonam; Dua, Madhuri; Yadav, Vikas

    2016-01-01

    Missing teeth are a common developmental abnormality in humans. It may manifest as absence of varying numbers of primary and/or secondary teeth. Early treatment and follow-up are the key to successful rehabilitation of young patients with congenitally missing teeth. It is critical that oral rehabilitation is started early to maintain and correct the oral functions. Mucosa borne removable prostheses are the commonly selected treatment options for the young patients who present with oligodontia or anodontia. This clinical report describes esthetic, functional, and psychological rehabilitation of a young boy with severe oligodontia in maxillary arch and anodontia in mandibular arch. The individualized conservative graded approach in prosthetic rehabilitation with removable acrylic prosthesis helped to achieve esthetics, functionality, and psychological benefits. PMID:27307674

  18. MIXED DENTITION SPACE ANALYSIS OF A SOUTHERN ITALIAN POPULATION: NEW REGRESSION EQUATIONS FOR UNERUPTED TEETH.

    Science.gov (United States)

    Cirulli, N; Ballini, A; Cantore, S; Farronato, D; Inchingolo, F; Dipalma, G; Gatto, M R; Alessandri Bonetti, G

    2015-01-01

    Mixed dentition analysis forms a critical aspect of early orthodontic treatment. In fact an accurate space analysis is one of the important criteria in determining whether the treatment plan may involve serial extraction, guidance of eruption, space maintenance, space regaining or just periodic observation of the patients. The aim of the present study was to calculate linear regression equations in mixed dentition space analysis, measuring 230 dental casts mesiodistal tooth widths, obtained from southern Italian patients (118 females, 112 males, mean age 15±3 years). Student’s t-test or Wilcoxon test for independent and paired samples were used to determine right/left side and male/female differences. On the basis of the sum of the mesiodistal diameters of the 4 mandibular incisors as predictors for the sum of the widths of the canines and premolars in the mandibular mixed dentition, a new linear regression equation was found: y = 0.613x+7.294 (r= 0.701) for both genders in a southern Italian population. To better estimate the size of leeway space, a new regression equation was found to calculate the mesiodistal size of the second premolar using the sum of the four mandibular incisors, canine and first premolar as a predictor. The equation is y = 0.241x+1.224 (r= 0.732). In conclusion, new regression equations were derived for a southern Italian population.

  19. Applicability of Two Universally Accepted Mixed Dentition Analysis ...

    African Journals Online (AJOL)

    Applicability of Two Universally Accepted Mixed Dentition Analysis on a Sample from ... Annals of Medical and Health Sciences Research ... Subjects and Methods: Study models were prepared from a sample of 100 patients (50 males and 50 ...

  20. Prevalência, necessidade de tratamento e fatores predisponentes do traumatismo na dentição permanente de escolares de 11 a 13 anos de idade Prevalence, treatment needs, and predisposing factors for traumatic injuries to permanent dentition in 11-13-year-old schoolchildren

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    J. Traebert

    2004-04-01

    Full Text Available Este estudo objetivou determinar a prevalência do traumatismo dentário na dentição permanente e observar associações com fatores predisponentes. Foi realizado um estudo transversal com escolares de 11 a 13 anos de Biguaçu, Santa Catarina, Brasil. Os exames foram realizados por um cirurgião-dentista utilizando os mesmos critérios do Children's Dental Health Survey do Reino Unido. Foram observados tipo de dano, tratamento providenciado e necessidade, overjet incisal, adequabilidade da cobertura labial, idade, sexo e nível de educação dos pais. Foram examinadas 2.260 crianças e as prevalências encontradas foram: 10,4%, 10,6% e 11,2% aos 11, 12 e 13 anos, respectivamente. A necessidade de tratamento foi de 6,3 incisivos por mil examinados. Escolares do sexo masculino e com overjetmaior que 5mm tiveram mais traumatismo dentário do que escolares do sexo feminino e com overjetincisal até 5mm. Cobertura labial inadequada e nível de educação dos pais não estiveram estatisticamente associados com o traumatismo dentário. Concluiu-se que ser do sexo masculino ou ter um overjetincisal maior do que 5mm aumenta a chance de sofrer traumatismo dentário.The objective of this study was to assess the prevalence of traumatic injuries to the permanent incisors and the association with clinical predisposing factors and parents' schooling. A cross-sectional survey was conducted with schoolchildren aged 11 to 13 years in Biguaçu, Brazil. Dental examinations were conducted by a dentist, and the criteria for traumatic dental injuries used in the children's dental health survey in the United Kingdom were adopted. the study recorded the type of damage sustained, treatment performed or needed, the size of incisal overjet, and whether lip coverage was adequate. Socio-demographic data included sex, age, and parents' level of schooling. a total of 2,260 children were examined, and prevalence rates were 10.4%, 10.6%, and 11.2% in 11, 12, and 13-year

  1. Management of a Compound Odontoma in the Primary Dentition.

    Science.gov (United States)

    Altay, Mehmet Ali; Ozgur, Beste; Cehreli, Zafer C

    2016-01-01

    Odontomas are the most common benign odontogenic tumors of the oral cavity; however, their occurrence in the primary dentition is an extremely rare condition. When associated with primary teeth, odontomas may lead to disturbances in tooth eruption, which often requires a multidisciplinary treatment approach. The purpose of this paper is to review the literature on odontomas of the primary dentition and discuss the management of a compound odontoma in a pediatric patient.

  2. Sequelae of trauma to primary maxillary incisors. I. Complications in the primary dentition.

    Science.gov (United States)

    Borum, M K; Andreasen, J O

    1998-02-01

    Two hundred and eighty-seven children with a total of 545 traumatized primary upper incisors were followed using standardized procedures until the age of 10. Extraction was the only treatment offered when intervention was necessary. The immediate as well as the long-term consequences of trauma were studied on the basis of this material. Consequences in the primary dentition comprised: color changes (53%), pulp necrosis (25%), pulp canal obliteration (36%), gingival retraction (6%), permanent displacement after luxation (5-22%), pathological root resorption (1-10%) as well as disturbances in physiological root resorption (4%) and, lastly, premature tooth loss (46%). In a multivariate analysis of the development of pulp necross in primary teeth after trauma, the following decisive factors were found: age of the patient at the time of injury, degree of displacement of the tooth as well as the degree of loosening and presence of crown fracture. The factors found to influence development of pulp canal obliteration were: displacement of the tooth at time of injury as well as detectable physiologic root resorption at time of trauma. The presence of crown fracture seemed to decrease the risk of obliteration. The need for scientifically based treatment strategies for managing and reducting complications after trauma in the primary dentition is stressed.

  3. Morphological alterations in the dentition of type I diabetes mellitus patients

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    Andamuthu Yamunadevi

    2014-01-01

    Full Text Available Introduction: Type 1 diabetes mellitus (DM is an endocrine disorder that occurs commonly in an age group, where the development of primary and permanent dentition takes place. As altered endocrine functions may affect the shape and size of teeth leading to dental anomalies, this study was conducted to look for the occurrence of any dental anomalies in type I DM patients. Materials and Methods: A diabetic camp was conducted at Alur Chandrashekharappa Memorial Hospital, Davangere, where 30 diabetic patients were examined and the impressions of their maxillary and mandibular arches were recorded. Age and sex matched controls were selected randomly, and similar recordings were done. Results: Type I diabetic patients showed statistically significant (P < 0.001 morphological alterations of total number of cusps, including presence of 6 th cusp in mandibular molars and extra cusps in mandibular premolars. Other alterations such as microdontia, flower shaped mandibular molars, prominent cusp of carabelli, and oblique ridge in maxillary molars were also noted. Severe attrition was found in 11 (36.6% of the diabetic patients, whereas the control group showed attrition only in 2 (6.8% patients. Conclusion: Remarkable morphological alterations do occur in the dentition of type I DM patients.

  4. Massive and permanent decline of symbiont bearing morozovellids and δ13C perturbations across the Early Eocene Climatic Optimum at the Possagno section (Southern Alps of northeastern Italy

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    V. Luciani

    2015-03-01

    Full Text Available The Early Eocene Climatic Optimum (EECO records the highest prolonged global temperatures over the past 70 Ma. Understanding the causes and timing of Eocene climate change remains a major challenge in Cenozoic paleoceanography, which includes the biotic response to climate variability and the changes among planktic foraminiferal assemblages across the EECO. The symbiont bearing and shallow dwelling genera Morozovella and Acarinina were important calcifiers in the tropical-subtropical early Paleogene oceans but almost completely disappeared at about 38 Ma, near the Bartonian/Priabonian boundary. We show here that morozovellids record a first critical step across the EECO through a major permanent decline in relative abundance from the Tethyan Possagno section and ODP Site 1051 in the western subtropical North Atlantic. Possible causes may include increased eutrophication, weak water column stratification, changes in ocean chemistry, loss of symbiosis and possible complex interaction with other microfossil groups. Relative abundances of planktic foraminiferal taxa at Possagno parallel negative shifts in both δ13C and δ18O of bulk sediment from Chron C24r to basal Chron C20r. The post-EECO stable isotopic excursions towards lighter values are of modest intensity. Significant though ephemeral modifications in the planktic foraminiferal communities occur during these minor isotopic excursions. These modifications are marked by pronounced increases in relative abundance of acarininids, in a manner similar to their behaviour during pre-EECO hyperthermals in the Tethyan settings, which suggest a pronounced biotic sensitivity to climate change of planktic foraminifera even during the post-EECO interval.

  5. Endodontic treatment in the primary dentition.

    Science.gov (United States)

    Koshy, Sajeev; Love, Robert M

    2004-08-01

    A number of factors are involved in the development of pulp and periapical disease in primary and permanent teeth, with dental caries being the main factor. Although these factors are similar, the clinical management of a primary or permanent tooth with pulp or periapical disease may be quite different. This is based mainly on the differences between the two types of teeth, with primary tooth longevity, coronal structural integrity, root canal morphology, and root anatomy being important features to be taken into account when treatment planning. This paper reviews some aspects of primary teeth and the various treatment options for the management of pulp and periapical disease.

  6. Applicability of the Moyers mixed dentition probability tables and new prediction aids for a contemporary population in India.

    Science.gov (United States)

    Philip, Nebu Ivan; Prabhakar, Manisha; Arora, Deepak; Chopra, Saroj

    2010-09-01

    The Moyers mixed dentition space analysis method is among the most commonly used in clinical practice for detecting tooth size-arch length discrepancies. In view of reported secular trends, racial, and sex differences in tooth sizes, the purposes of this study were to evaluate the applicability of Moyers probability tables in a contemporary orthodontic population of India and to formulate more accurate mixed dentition prediction aids. Odontometric data were collected from 300 male and 300 female subjects of Indian descent, who had fully erupted mandibular permanent incisors and maxillary and mandibular canines and premolars. We measured the mesiodistal crown widths with vernier scale dial calipers. The odontometric values obtained were then subjected to statistical and linear regression analysis. All tooth groups showed significant differences (P Moyers pattern. Significant differences (P Moyers tables at almost all percentile levels, including the recommended 75% and 50% levels. We believe that these new prediction aids could be considered for a more precise mixed dentition space analysis in Indian children. 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  7. Orthodontic management of a periodontally compromised dentition

    Directory of Open Access Journals (Sweden)

    Prashant K Zaveri

    2016-01-01

    Full Text Available Malocclusion superimposed with severe periodontitis may present a great challenge to clinicians while providing orthodontic treatment due the episodic and site-specific nature of the disease with risk of rapid tissue breakdown. However, orthodontic treatment in such situation may contribute significantly to the overall rehabilitation both functionally and esthetically. In this article, a case report outlines a combined periodontic-orthodontic management of compromised dentition. A 37-year-old female patient with significant medical history was treated for Class II Division 1 type of malocclusion associated with spaced upper and lower anterior teeth, deep overbite, and increased overjet, superimposed with chronic generalized periodontitis and bone loss. Treatment was completed using temporary anchorage devices assisted strategically applied force and modified tandem retraction biomechanics amidst management of acute inflammatory episodes during and mucogingival complication after treatment. Affected areas healed very well after post-orthodontic periodontal treatment with minimal pocket depth, and bleeding on probing, and a healthy zone of attached gingiva at the follow up visits. The orthodontic results lead to improvement in patient's facial profile, lip posture, and correction of protrusion which addressed her main concern. One year follow-up shows good orthodontic and periodontic stability. The report highlights the importance of identifying “at risk” individuals and continuous monitoring of disease status during treatment. Despite all precautionary measures, a flare-up during the treatment can be anticipated.

  8. Full mouth rehabilitation of the patient with severely worn dentition: a case report.

    Science.gov (United States)

    Song, Mi-Young; Park, Ji-Man; Park, Eun-Jin

    2010-09-01

    The severe wear of anterior teeth facilitates the loss of anterior guidance, which protects the posterior teeth from wear during excursive movement. The collapse of posterior teeth also results in the loss of normal occlusal plane and the reduction of the vertical dimension. This case report describes 77-year-old female, who had the loss of anterior guidance, the severe wear of dentition, and the reduction of the vertical dimension. Occlusal overlay splint was used after the decision of increasing vertical dimension by anatomical landmark, facial and physiologic measurement. Once the compatibility of the new vertical dimension had been confirmed, interim fixed restoration and the permanent reconstruction was initiated. This case reports that a satisfactory clinical result was achieved by restoring the vertical dimension with an improvement in esthetics and function.

  9. Essure Permanent Birth Control

    Science.gov (United States)

    ... Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... System Essure is a a permanently implanted birth control device for women (female sterilization). Implantation of Essure ...

  10. Bite force and state of dentition.

    Science.gov (United States)

    Helkimo, E; Carlsson, G E; Helkimo, M

    1977-01-01

    The maximal bite force and the strength of the finger-thumb grip of 125 Skolt Lapps, aged 15 to 65, was measured with a specially devised apparatus. The bite force was measured with the biting fork placed between the first molars and between the incisors, respectively. The finger-thumb grip was measured by letting the subject press the prongs of the fork between the thumb and forefinger of each hand as hard as possible. The range of inter-individual variation of the maximal bite force and finger-thumb grip was great. The mean values were higher for the males than for the females. In the males the maximal bite force thus measured in the molar region was 39 kg (382 N) and 18 kg (176 N) in the incisor region. The corresponding values for the females were 22 kg (216 N) and 11 kg (108 N). The finger-thumb grip strength for males was, on the average, 10 kg (98 N); that of the females, 7 KG (69 N). The average difference in bite force between the men and the women was larger in the group with natural teeth than in the one with complete dentures. The values found for the bite force decreased with increasing age, especially for the females. Most of this reduction with increasing age was probably due to the age-dependent deterioration of the dentition. In both sexes the bite force was notably smaller among the denture wearers than among the dentate persons. The number of natural teeth varied closely with the bite force, i.e. the greater number of natural teeth the greater the bite force.

  11. Ankylosis of primary molar along with congenitally missing first permanent molar

    Directory of Open Access Journals (Sweden)

    Suprabha B

    2006-05-01

    Full Text Available Ankylosis of primary mandibular molars has been routinely found to be associated with various developmental disturbances in permanent dentition such as aplasia of the succedaneous tooth, ectopic eruption of the premolar, infraoclusion of the ankylosed tooth leading to tipping of the first permanent molar etc. This article describes a rare case where there was ankylosis of a mandibular second primary molar along with congenitally missing first permanent molar which resulted in the transposition of second premolar. Treatment options and prognosis of the case are discussed.

  12. Carbonated soft drinks and dental caries in the primary dentition.

    Science.gov (United States)

    Sohn, W; Burt, B A; Sowers, M R

    2006-03-01

    We analyzed fluid intake data among children aged 2-10 years from a 24-hour dietary recall interview in the NHANES III (1988-94) to investigate the effect of high consumption of carbonated soft drinks on caries in the primary dentition. We used cluster analysis to determine fluid consumption patterns. Four distinct fluid consumption patterns were identified: high carbonated soft drinks, high juice, high milk, and high water. About 13% of children had a high carbonated soft drink consumption pattern; they also had a significantly higher dental caries experience in the primary dentition than did children with other fluid consumption patterns. A fluid intake pattern comprised mainly of milk, water, or juice was less likely to be associated with dental caries. Findings of this study suggest that high consumption of carbonated soft drinks by young children is a risk indicator for dental caries in the primary dentition and should be discouraged.

  13. Teeth Number Anomalies in Permanent Dentition among Non-Syndromic Dental Patients

    OpenAIRE

    Isik Aslan, Belma; Zafersoy Akarslan, Zühre

    2013-01-01

    The aim of this study was to establish teeth number anomalies in relation to gender, tooth type, location, distribution pattern and the association between frequently missing teeth among a group of dental patients in Turkey. A total of 378 non-syndromic patients (240 females and 138 males) with an age range of 7–45 (X±SD=22.07±3.6) having evidence of absent or excess teeth were evaluated in the study. Pearson Chi-square, Fisher’s exact, McNemar and Kappa coefficients were used for statisti...

  14. Teeth number anomalies in permanent dentition among non-syndromic dental patients.

    Science.gov (United States)

    Aslan, Belma Işik; Akarslan, Zühre Zafersoy

    2013-03-01

    The aim of this study was to establish teeth number anomalies in relation to gender, tooth type, location, distribution pattern and the association between frequently missing teeth among a group of dental patients in Turkey. A total of 378 non-syndromic patients (240 females and 138 males) with an age range of 7-45 (x +/- SD = 22.07 +/- 3.6) having evidence of absent or excess teeth were evaluated in the study. Pearson Chi-square, Fisher's exact, McNemar and Kappa coefficients were used for statistical analysis. 237 patients had a total of 546 congenitally missing teeth and 141 had 185 excess teeth. Congenitally missing teeth were more commonly seen rather than the presence of supernumerary teeth. Difference was determined in the frequent locations of congenital missing and supernumerary teeth. The most frequent missing tooth type was found to be the mandibular second premolar (26.6%), while the majority of supernumerary teeth were located in the anterior region of the maxillary arch (37.9%). Both teeth number anomalies were more commonly seen among females. In hypodontia cases the occurrence of symmetrical agenesis of laterals and second premolars in maxilla; centrals and second premolars in mandible was notable. Agenesis of mandibular centrals was found to be associated with maxillary lateral agenesis in males. Also higher prevalence of molar teeth agenesis was determined in the occurrence of at least 4 teeth agenesis. These findings will serve as information about the contemporary demographic pattern of teeth number anomalies among non-syndromic Turkish dental patients and can provide evidence that agenesis of some teeth symmetrically or together are the products of the same genetic mechanisms.

  15. Orthodontic extrusion in the transitional dentition: a simple technique.

    LENUS (Irish Health Repository)

    Darby, Laura J

    2009-11-01

    Extrusion of teeth may be necessary in cases of delayed eruption, primary retention, traumatically intruded teeth, or subgingivally fractured teeth. Removable appliances are advantageous, as anchorage is not as tooth-dependant as in the case of fixed appliances. They are cost-effective, operator friendly, and a valuable treatment option to consider in cases where extrusion of anterior teeth in the transitional dentition is necessary. The purpose of this paper was to describe a simple, cost-effective technique using a removable appliance for extrusion of incisors in the transitional dentition.

  16. Bonding durability of dental sealants to deciduous and permanent teeth

    OpenAIRE

    MOURA, Sandra Kiss; Lemos,Letícia Vargas Freire Martins; Myszkovisk, Suellen; Provenzano, Maria Gisette Arias; Balducci,Ivan; Myaki, Silvio Issao [UNESP

    2014-01-01

    AIM: To evaluate the bonding durability of materials used as sealants on different dentitions. METHODS: Deciduous (D) and permanent (P) molars were divided into four groups (n=5) and sealed with Fluroshield (F) and OptiBond FL (FL). Blocks of composite resin were built, stored in distilled water (24 h/37 °C), sectioned into 0.8 mm2 and tested at tensile (0.5 mm/min) after 24 h and 6 months. The fractures were observed and classified into adhesive, cohesive or mixed types. The data were a...

  17. Esthetic rehabilitation of crowded and protruded anterior dentition

    Directory of Open Access Journals (Sweden)

    Cecilia G. J. lunardhi

    2009-03-01

    Full Text Available Background: Recent trends put estheticrehabilitationas a demandingtreatmentin order to correct malpositionedanteriordentition. This is enhanced by the patient’s background, especially careers that require prime appearance for the public. Purpose: To describe that even though there are many treatment alternatives and procedures, esthetic rehabilitation on crowded and protruded anterior dentition using endodontic treatment, cast posts and all ceramic crowns, can improve patient’s appearance. Case: This article presents a case report on esthetic rehabilitation of crowded and protruded anterior dentition. Treatment was done due to patient’s refusal in receiving orthodontic treatment. The patient requested esthetic rehabilitation as an expectation for faster and instant esthetic result. Case management: Endodontic treatment was done to the involved dentition prior to the final restoration. Cast posts and all ceramic crowns were used as final restoration to correct the crowded and protruded anterior teeth. Conclusion: Esthetic rehabilitation can be done successfully on crowded and protruded anterior dentition. Instant result could be achieved by this treatment. This is supported by the fact that dentists should be aware of not only choosing the right treatment and materials but also patient’s expectations and conditions.

  18. On some Anomalies in the Dentition of Phoca hispida

    NARCIS (Netherlands)

    Lönnberg, Einar

    1922-01-01

    Variation with regard to the dentition is perhaps a more common occurrence among the Seals than among most other groups of Mammals. It is quite probable, that this stands in connection with the more or less reduced condition of the teeth of these animals. The variation in the dental formula can make

  19. Early Treatment of Class III Malocclusion: A Boon or a Burden?

    Science.gov (United States)

    Begum Khan, Mohammadi; Karra, Arjun

    2014-05-01

    This article presents a case of class III malocclusion, a female patient aged 8 years treated in early stage of its recognition, i.e. treated in early mixed dentition stage, utilizing orthopedic appliance for its correction, utilizing both rapid maxillary expansion and face mask approach. After the skeletal base correction as part of phase of phase I therapy, a retentive plate was given and patient was asked to report every 6 months for review and monitoring of her growth pattern and phase II treatment planning after the eruption of all permanent teeth. How to cite this article: Khan MB, Karra A. Early Treatment of Class III Malocclusion: A Boon or a Burden? Int J Clin Pediatr Dent 2014;7(2):130-136.

  20. Influence of the socioeconomic status on the prevalence of malocclusion in the primary dentition

    Directory of Open Access Journals (Sweden)

    Thiene Silva Normando

    2015-02-01

    Full Text Available OBJECTIVE: To assess the influence of socioeconomic background on malocclusion prevalence in primary dentition in a population from the Brazilian Amazon. METHODS: This cross-sectional study comprised 652 children (males and females aged between 3 to 6 years old. Subjects were enrolled in private preschools (higher socioeconomic status - HSS, n = 312 or public preschools (lower socioeconomic status - LSS, n = 340 in Belém, Pará, Brazil. Chi-square and binomial statistics were used to assess differences between both socioeconomic groups, with significance level set at P < 0.05. RESULTS: A high prevalence of malocclusion (81.44% was found in the sample. LSS females exhibited significantly lower prevalence (72.1% in comparison to HSS females (84.7%, particularly with regard to Class II (P < 0.0001, posterior crossbite (P = 0.006, increased overbite (P = 0.005 and overjet (P < 0.0001. Overall, malocclusion prevalence was similar between HSS and LSS male children (P = 0.36. Early loss of primary teeth was significantly more prevalent in the LSS group (20.9% in comparison to children in the HSS group (0.9%, for both males and females (P < 0.0001. CONCLUSION: Socioeconomic background influences the occurrence of malocclusion in the primary dentition. In the largest metropolitan area of the Amazon, one in every five LSS children has lost at least one primary tooth before the age of seven.

  1. Influence of the socioeconomic status on the prevalence of malocclusion in the primary dentition

    Science.gov (United States)

    Normando, Thiene Silva; Barroso, Regina Fátima Feio; Normando, David

    2015-01-01

    OBJECTIVE: To assess the influence of socioeconomic background on malocclusion prevalence in primary dentition in a population from the Brazilian Amazon. METHODS: This cross-sectional study comprised 652 children (males and females) aged between 3 to 6 years old. Subjects were enrolled in private preschools (higher socioeconomic status - HSS, n = 312) or public preschools (lower socioeconomic status - LSS, n = 340) in Belém, Pará, Brazil. Chi-square and binomial statistics were used to assess differences between both socioeconomic groups, with significance level set at P overjet (P < 0.0001). Overall, malocclusion prevalence was similar between HSS and LSS male children (P = 0.36). Early loss of primary teeth was significantly more prevalent in the LSS group (20.9%) in comparison to children in the HSS group (0.9%), for both males and females (P < 0.0001). CONCLUSION: Socioeconomic background influences the occurrence of malocclusion in the primary dentition. In the largest metropolitan area of the Amazon, one in every five LSS children has lost at least one primary tooth before the age of seven. PMID:25741828

  2. Marxism as permanent revolution

    NARCIS (Netherlands)

    van Ree, E.

    2013-01-01

    This article argues that the 'permanent revolution' represented the dominant element in Karl Marx and Friedrich Engels' political discourse, and that it tended to overrule considerations encapsulated in 'historical materialism'. In Marx and Engels's understanding, permanent revolution did not repres

  3. Marxism as permanent revolution

    NARCIS (Netherlands)

    van Ree, E.

    2013-01-01

    This article argues that the 'permanent revolution' represented the dominant element in Karl Marx and Friedrich Engels' political discourse, and that it tended to overrule considerations encapsulated in 'historical materialism'. In Marx and Engels's understanding, permanent revolution did not

  4. Early-onset, severe lipoatrophy in a patient with permanent neonatal diabetes mellitus secondary to a recessive mutation in the INS gene.

    Science.gov (United States)

    Rachmiel, Marianna; Rubio-Cabezas, Oscar; Ellard, Sian; Hattersley, Andrew T; Perlman, Kusiel

    2012-09-01

    We describe a case of neonatal diabetes due to a homozygous mutation (c.3 G>T) at the INS gene, leading to lack of insulin expression and severe hyperglycemia from day one of life requiring permanent insulin replacement therapy. The genetic loss of endogenous insulin production likely led to lack of immune tolerance to insulin, with resultant autoantibody production against exogenous insulin and progressive immune-mediated lipoatrophy at injection sites.

  5. Mesiodistal crown diameters of the primary and permanent teeth in southern Chinese--a longitudinal study.

    Science.gov (United States)

    Yuen, K K; So, L L; Tang, E L

    1997-12-01

    The mesiodistal crown diameters of the primary and permanent teeth were measured on serial casts of 112 Hong Kong Southern Chinese (61 males and 51 females) taken at 5.68 and 12.31 years of age. None of the teeth showed significant sex difference in bilateral asymmetry, and significant bilateral asymmetry was found only for the upper primary second molars. The asymmetries were small and the sizes of the antimeres were averaged. Posterior teeth were generally less variable than anterior teeth in both dentitions in Chinese, which is contrary to other reports, but the anterior tooth of each morphological class was, in general, less variable than the posterior member. Male teeth were larger than those of females except for the lower central and lateral incisors in both dentitions, but the difference was not statistically significant. None of the primary teeth nor three of the permanent teeth were found to have significant sex differences in size. Percentage sexual dimorphism ranged from 0.06 to 1.97 per cent for the primary teeth and from 0.36 to 5.27 per cent for the permanent teeth. In the primary dentition, molars were the most dimorphic teeth in both arches, while upper incisors and lower canine were the least dimorphic teeth in their own arch. Among the permanent teeth, the canines were the most dimorphic and the incisors were among the least dimorphic teeth in both arches. Tooth sizes in both dentitions were, in general, larger than those of the Caucasians, comparable with Northern Chinese, but smaller than those of Australian Aboriginals.

  6. Prevalence of enamel defects and associated risk factors in both dentitions in preterm and full term born children

    Directory of Open Access Journals (Sweden)

    Vanessa Resende Nogueira Cruvinel

    2012-06-01

    Full Text Available OBJECTIVES: The aim of this study was to evaluate the prevalence of enamel defects and their risk factors on primary and permanent dentitions of prematurely born children and full-term born children born at Regional Hospital of Asa Sul, Brasília, DF, Brazil. MATERIAL AND METHODS: Eighty 5-10-year-old children of both genders were examined, being 40 born prematurely (G1 and 40 born full term (G2. The demographic variables, medical history and oral health behaviors were retrieved using a questionnaire and data obtained from clinical examination were recorded. The teeth were examined and the presence of enamel defects was diagnosed according to the DDE Index and registered in odontograms. Subsequently, the defects were categorized in four groups according to one of the criteria proposed in 1992 by the FDI Commission on Oral Health, Research and Epidemiology. Kruskal-Wallis, Chi-square, Kappa, Mann-Whitney tests and logistic regression were used for statistical analysis. RESULTS: 75% of total sample had enamel defects. There was a major prevalence of hypoplasia of the enamel in G1 (p<0.001. There was a significant relationship between low weight and presence of the imperfections on the enamel in G1 on the primary dentition. The logistic regression model showed that the other risk factors such as monthly per capita family income, educational level, dietary and hygiene habits, fluoride exposure, trauma, and diseases were not associated with enamel defects and caries. CONCLUSIONS: Pre-term labor can be a predisposing factor for the presence of the enamel hypoplasia in the primary dentition.

  7. Dentinogenesis imperfecta: the importance of early treatment.

    Science.gov (United States)

    Delgado, Antonio Carlos; Ruiz, Matilde; Alarcón, Jose Antonio; González, Encarnación

    2008-03-01

    Dentinogenesis imperfecta, also known as hereditary opalescent dentin, is a dentin development disorder with autosomal dominant transmission that affects both the primary and permanent dentition. A case is reported of a family in which the mother and her 6- and 20-year-old children were diagnosed with dentinogenesis imperfecta type II. The mouths of these patients illustrate the progressive deterioration of affected teeth if not adequately treated. The treatment of the 6-year-old son is described, and therapeutic approaches to this disorder in primary and permanent dentition are reviewed. This family exemplifies the need for the earliest possible diagnosis and treatment of dentinogenesis imperfecta to prevent extensive deterioration of the dentition and occlusion.

  8. [Clinical anatomy of the horse: teeth and dentition].

    Science.gov (United States)

    Staszyk, C

    2015-01-01

    The routine inspection of the equine oral cavity allows a numerical assessment of the teeth and provides information about positional changes within the dentition. By use of appropriate dental equipment, the occlusal surfaces of all teeth can be inspected and diagnosed. However, neither the teeth nor their occlusal surfaces are constant structures. Instead, equine teeth and, in particular, their occlusal surfaces are subjected to continuous morphological and positional changes due to the effects of aging and the equine-specific high amount of occlusal wear. Therefore, it is mandatory to define anatomical criteria, which allow us to distinguish between anatomical variations and pathological conditions. Moreover, an unambiguous nomenclature with regard to the equine-specific dental anatomy is essential. This article provides a tutorial overview of the equine dental anatomy as well as recent findings in the field of equine dentistry. Special attention is paid to dynamic changes within both individual teeth and dentition.

  9. Ecological and phylogenetic influences on maxillary dentition in snakes

    Directory of Open Access Journals (Sweden)

    Kate Jackson

    2010-12-01

    Full Text Available The maxillary dentition of snakes was used as a system with which to investigate the relative importance of the interacting forces of ecological selective pressures and phylogenetic constraints indetermining morphology. The maxillary morphology of three groups of snakes having different diets, with each group comprising two distinct lineages — boids and colubroids — was examined. Our results suggest that dietary selective pressures may be more significantthan phylogenetic history in shaping maxillary morphology.

  10. [Commentaries on the Treatise on first dentition by M. Baumes].

    Science.gov (United States)

    Zarranz, A

    1996-12-01

    Dr. Baumes a book, physician at the Montpellier Faculty (France), was written before the French Revolution and published in 1806. Its reading provides us with valuable information on dental knowledges of the 18th century and usual treatments at that time when problems arose during the 1st dentition. This 387 pages book has an unique illustration: a scalpel is drawn while used for incising the gums of little children.

  11. Prevalence of mesiodens in orthodontic patients with deciduous and mixed dentition and its association with other dental anomalies.

    Science.gov (United States)

    Lara, Tulio Silva; Lancia, Melissa; da Silva Filho, Omar Gabriel; Garib, Daniela Gamba; Ozawa, Terumi Okada

    2013-01-01

    To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment plan accomplished; and associated dental anomalies. The frequency of dental anomalies in the sample was compared to reference values for the general population using the chi-square test, with a significance level set at 5%. The prevalence of mesiodens was 1.5% more common among males (1.5:1). Most of the mesiodens were non-erupted (75%) and in a vertical position, facing the oral cavity. Extraction of the mesiodens was the most common treatment. The main complications associated with mesiodens were: delayed eruption of permanent incisors (34.28%) and midline diastema (28.57%). From all the dental anomalies analyzed, only the prevalence of maxillary lateral incisor agenesis was higher in comparison to the general population. There was a low prevalence of mesiodens (1.5%) in deciduous and mixed dentition and the condition was not associated with other dental anomalies, except for the maxillary lateral incisor agenesis.

  12. Prevalence of mesiodens in orthodontic patients with deciduous and mixed dentition and its association with other dental anomalies

    Directory of Open Access Journals (Sweden)

    Tulio Silva Lara

    2013-12-01

    Full Text Available OBJECTIVE: To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. MATERIAL AND METHODS: Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender ; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment plan accomplished; and associated dental anomalies. The frequency of dental anomalies in the sample was compared to reference values for the general population using the chi-square test (c², with a significance level set at 5%. RESULTS: The prevalence of mesiodens was 1.5% more common among males (1.5:1. Most of the mesiodens were non-erupted (75% and in a vertical position, facing the oral cavity. Extraction of the mesiodens was the most common treatment. The main complications associated with mesiodens were: delayed eruption of permanent incisors (34.28% and midline diastema (28.57%. From all the dental anomalies analyzed, only the prevalence of maxillary lateral incisor agenesis was higher in comparison to the general population. CONCLUSION: There was a low prevalence of mesiodens (1.5% in deciduous and mixed dentition and the condition was not associated with other dental anomalies, except for the maxillary lateral incisor agenesis.

  13. The early distribution and possible role of nerves during odontogenesis.

    Science.gov (United States)

    Chiego, D J

    1995-02-01

    Neural crest cells migrate along specific pathways to reach the mandibular and maxillary arches where they condense under specific areas of the ectoderm which will give rise to the primary and permanent dentition. In the mouse, the trigeminal ganglion becomes evident on E9 and the superior cervical sympathetic ganglion E13. Several studies have suggested that nerves in the vicinity of the developing teeth could influence the surrounding tissues and initiate tooth development, whereas other investigators have suggested that tooth development will proceed without an intact innervation. Innervation of the dental papilla has been reported as early as the cap stage in human teeth using an antibody to PGP 9.5. A large variety of putative neurotransmitters have been localized in the nerves of the dental pulp. Many of the putative neurotransmitters function in vasoregulation while others have unknown functions. A hypothesis is presented describing a possible signal transduction pathway between odontoblasts and nerve terminals.

  14. Ectoderm, endoderm, and the evolution of heterodont dentitions.

    Science.gov (United States)

    Ohazama, Atsushi; Haworth, Kim E; Ota, Masato S; Khonsari, Roman H; Sharpe, Paul T

    2010-06-01

    Mammalian dentitions consist of different shapes/types of teeth that are positioned in different regions of the jaw (heterodont) whereas in many fish and reptiles all teeth are of similar type (homodont). The process by which heterodont dentitions have evolved in mammals is not understood. In many teleosts teeth develop in the pharynx from endoderm (endodermal teeth), whereas mammalian teeth develop from the oral ectoderm indicating that teeth can develop (and thus possibly evolve) via different mechanisms. In this article, we compare the molecular characteristics of pharyngeal/foregut endoderm with the molecular characteristics of oral ectoderm during mouse development. The expression domains of Claudin6, Hnf3beta, alpha-fetoprotein, Rbm35a, and Sox2 in the embryonic endoderm have boundaries overlapping the molar tooth-forming region, but not the incisor region in the oral ectoderm. These results suggest that molar teeth (but not incisors) develop from epithelium that shares molecular characteristics with pharyngeal endoderm. This opens the possibility that the two different theories proposed for the evolution of teeth may both be correct. Multicuspid (eg. molars) having evolved from the externalization of endodermal teeth into the oral cavity and monocuspid (eg. incisors) having evolved from internalization of ectodermal armour odontodes of ancient fishes. The two different mechanisms of tooth development may have provided the developmental and genetic diversity on which evolution has acted to produce heterodont dentitions in mammals.

  15. Applicability of Moyers analysis in mixed dentition: A systematic review

    Directory of Open Access Journals (Sweden)

    Mariana de Aguiar Bulhões Galvão

    2013-12-01

    Full Text Available INTRODUCTION: Moyers analysis is widely used for analyzing mixed dentition, however, the accuracy of its theoretical probability tables has been recently questioned. Taking into consideration the fact the mixed dentition analysis is of paramount importance to precisely determine the space needed for alignment of canines and premolars, this research aimed at objectively assessing in the literature such an important step for orthodontic diagnosis. METHODS: A computerized search involving articles published on PubMed and Lilacs between 1990 and September, 2011 was conducted in accordance with the method described in the Cochrane 5.1.0 handbook. RESULTS: The research resulted in a sample composed of 629 articles. The inclusion criteria were: Articles using the Moyers analysis with a sample greater or equal to 40 patients. Conversely, the exclusion criteria were: Dental casts of patients with syndromes or oral cleft, researches conducted with a literature review, only, or clinical case reports and researches conducted before 1990. For this systematic review, 19 articles were selected. CONCLUSION: Based on the literature available, we can conclude that the Moyers mixed dentition analysis must be carefully used, since the majority of the articles analyzed showed that the probability of 75% was not as accurate as expected, leading to the need of adapting the probability levels depending on the study population.

  16. Signs and symptoms of temporomandibular joint dysfunction in children with primary dentition.

    Science.gov (United States)

    Bonjardim, Leonardo Rigoldi; Gaviao, Maria Beatriz Duarte; Carmagnani, Fabiola Grammatico; Pereira, Luciano Jose; Castelo, Paula Midori

    2003-01-01

    The presence of signs and symptoms of TMD in 99 children with primary dentition was evaluated through clinical exam and a questionnaire. The results showed that 34.34% presented signs and/or symptoms of TMD. Among the children with symptoms, 50% presented at least one sign or more, differing significantly from the ones without symptoms, and from those 21.6% presented sign (p = 0.0185). The most prevalent symptom was frequent headache (7.07%) followed by jaw pain (4.04%), earache (3.03%) and difficulty in swallowing (3.03%). The most prevalent sign was jaw deviation (18.18%) followed by occlusal interferences (7.07%), asymmetric condylar movement (5.05%) and TMJ sounds (3.03%). We concluded that signs and symptoms of TMD are present in early ages, even though in a small number of children.

  17. Anterior crossbite correction in primary and mixed dentition with removable inclined plane (Bruckl appliance).

    Science.gov (United States)

    Jirgensone, Irena; Liepa, Andra; Abeltins, Andris

    2008-01-01

    Anterior crossbite correction in early mixed dentition is highly recommended as this kind of malocclusion do not diminish with age. Uncorrected anterior crossbite may lead to abnormal wear of the lower incisors, dental compensation of mandibular incisors leading to thinning of labial alveolar plate and/or gingival recession. There are several methods for solving this problem. In this article we would like to describe removable inclined plane. This is a removable simple functional appliance on the lower arch (jaw), which works as inclined plane. One of the advantage of the Bruckl appliance is that it can also be used as retention appliance after active treatment as well as it is possible to add acrylic teeth if necessary. Therefore it can be used as a removable partial denture in lower jaw in case where there is a premature loss of the primary teeth. The use of this appliance is illustrated with three cases.

  18. Esthetic restoration of infra-occluded retained primary mandibular incisors with all-ceramic crowns in adult dentition.

    Science.gov (United States)

    Hsu, Kuang-Wei; Shen, Yu-Fu

    2004-12-01

    The prevalence of hypodontia is reported to be between 1.5% to 10% in the permanent dentition. In the anterior teeth, maxillary lateral incisors and mandibular central incisors are the most frequently involved teeth. This causes esthetic problems for the patient. Several reports have focused on restoration of retained maxillary primary anterior teeth, but none have described restoration of retained mandibular primary incisors. This clinical report describes the restoration of infra-occluded retained primary mandibular central incisors of a 17 year-old girl diagnosed with hypodontia. All-ceramic crowns made with computer-aided design/ computer-aided manufacturing technology were used to restore the teeth incisally and interproximally. Due to a relatively short root length and inadequate crown-root ratio, the primary mandibular central incisors were splinted and adjusted to distribute the protrusive force evenly across the maxillary and mandibular incisors. Functional and esthetic results were achieved.

  19. Molecular patterning of the mammalian dentition

    Science.gov (United States)

    Lan, Yu; Jia, Shihai; Jiang, Rulang

    2014-01-01

    Four conserved signaling pathways, including the bone morphogenetic proteins (Bmp), fibroblast growth factors (Fgf), Sonic hedgehog (Shh), and Wingless-related (Wnt) pathways, are each repeatedly used throughout tooth development. Inactivation of any of these resulted in early tooth developmental arrest in mice. The mutations identified thus far in human patients with tooth agenesis also affect these pathways. Recent studies show that these signaling pathways interact through positive and negative feedback loops to regulate not only morphogenesis of individual teeth but also tooth number, shape, and spatial pattern. Increased activity of each of the Fgf, Shh, and canonical Wnt signaling pathways revitalizes development of the physiologically arrested mouse diastemal tooth germs whereas constitutive activation of canonical Wnt signaling in the dental epithelium is able to induce supernumerary tooth formation even in the absence of Msx1 and Pax9, two transcription factors required for normal tooth development beyond the early bud stage. Bmp4 and Msx1 act in a positive feedback loop to drive sequential tooth formation whereas the Osr2 transcription factor restricts Msx1-mediated expansion of the mesenchymal odontogenic field along both the buccolingual and anteroposterior axes to pattern mouse molar teeth in a single row. Moreover, the ectodermal-specific ectodysplasin (EDA) signaling pathway controls tooth number and tooth shape through regulation of Fgf20 expression in the dental epithelium, whereas Shh suppresses Wnt signaling through a negative feedback loop to regulate spatial patterning of teeth. In this article, we attempt to integrate these exciting findings in the understanding of the molecular networks regulating tooth development and patterning. PMID:24355560

  20. Talon Cusp On Permanent Maxillary Canine: A Rare Case Report

    Directory of Open Access Journals (Sweden)

    D.N. Chandan

    2012-07-01

    Full Text Available teeth are varied. One such rare anomaly affecting the shape of anterior teeth is taloncusp. It is an accessory cusp-like projection found on lingual or labial surfaces of theupper or lower incisors, unilaterally or bilaterally in both dentitions. It is composed ofnormal enamel and dentine, with or without pulp. It is thought to develop as a result ofevagination on the surface of a tooth during morphodifferentiation stage. Reportedincidence is 0.04-10%, with higher prevalence in males. It is more common inpermanent dentition with a predilection for maxillary lateral incisors (55%, followed bycentral incisors (36% and canines (9%. Talon cusp may cause problems like irritationof tongue during speech and mastication, occlusal interference, caries susceptibility anddisplacement of the affected tooth, and esthetics. Its treatment ranges from applicationof sealant to gradual reduction to root canal therapy. Early diagnosis of talon cusp andits treatment can avoid complications related to this anomaly.

  1. Oscillating Permanent Magnets.

    Science.gov (United States)

    Michaelis, M. M.; Haines, C. M.

    1989-01-01

    Describes several ways to partially levitate permanent magnets. Computes field line geometries and oscillation frequencies. Provides several diagrams illustrating the mechanism of the oscillation. (YP)

  2. Evaluation of the Mesiodistal Crown Sizes of the Remaining Dentition in Patients with Hypodontia, between 12 and 16 Years of Age

    Directory of Open Access Journals (Sweden)

    Albena Reshitaj

    2013-09-01

    Full Text Available Objective: This study evaluated the mesiodistal crown sizes of the remaining dentition in patients affected with hypodontia, compared with the control group possessing complete dentition. Methods: Panoramic radiographs of the patients treated in the Department of Orthodontics, Dental School - branch of Medical Faculty – University of Pristina, were reviewed to select a sample of 22 cases with agenesis of one or more permanent teeth, except the third molars (hypodontia group. A control group included 22 patients with complete dentition. Dental casts were measured for both groups. The patients ranged in age from 12 to 16 years. Mesiodistal crown dimensions were recorded by measuring all erupted teeth on study models with a manual caliper. Statistical calculation was performed using SPSS 15.0. Paired samples t-test was used to detect the statistical differences in tooth width measurements between the two groups. The significance level was predetermined at α = 0.05.Results: The mean age of the patients in the hypodontia group was 14.55±1.57 years, while that of the control group was 14.23±1.11. The most common congenital missing teeth were the upper lateral incisors (46.16% followed by the upper first premolars (11.54%. We found significant differences between the groups in tooth size for the maxillary arch central incisors and the maxillary arch molar right quadrant, while in the left quadrant differences between the two groups were observed in the central incisor (P<0.05. However, we did not observe any significant differences between the groups with respect to tooth size for the lower jaw. Conclusion: The reduced tooth size was evident except in the posterior segment right molar in the hypodontia group. This should be taken into consideration during treatment planning and deciding upon the treatment mechanics in order to achieve functional occlusion and an esthetic dentition at the culmination of the orthodontic treatment.

  3. Influence of sex and ethnic tooth-size differences on mixed-dentition space analysis

    Science.gov (United States)

    Altherr, Edward R.; Koroluk, Lorne D.; Phillips, Ceib

    2013-01-01

    Introduction Most mixed-dentition space analyses were developed by using subjects of northwestern European descent and unspecified sex. The purpose of this study was to determine the predictive accuracy of the Tanaka-Johnston analysis in white and black subjects in North Carolina. Methods A total of 120 subjects (30 males and 30 females in each ethnic group) were recruited from clinics at the University of North Carolina School of Dentistry. Ethnicity was verified to 2 previous generations. All subjects were less than 21 years of age and had a full complement of permanent teeth. Digital calipers were used to measure the mesiodistal widths of all teeth on study models fabricated from alginate impressions. The predicted widths of the canines and the premolars in both arches were compared with the actual measured widths. Results In the maxillary arch, there was a significant interaction of ethnicity and sex on the predictive accuracy of the Tanaka-Johnston analysis (P = .03, factorial ANOVA). The predictive accuracy was significantly overestimated in the white female group (P <.001, least square means). In the mandibular arch, there was no significant interaction between ethnicity and sex (P = .49). Conclusions The Tanaka-Johnston analysis significantly overestimated in females (P <.0001) and underestimated in blacks (P <.0001) (factorial ANOVA). Regression equations were developed to increase the predictive accuracy in both arches. (Am J Orthod Dentofacial Orthop 2007;132:332-9) PMID:17826601

  4. Educational material of dental anatomy applied to study the morphology of permanent teeth.

    Science.gov (United States)

    Siéssere, Selma; Vitti, Mathias; de Sousa, Luiz Gustavo; Semprini, Marisa; Regalo, Simone Cecílio Hallak

    2004-01-01

    The purpose of this report is to present educational material that would allow the dental student to learn to easily identify the morphologic characteristics of permanent teeth, and how they fit together (occlusion). In order to do this, macro models of permanent teeth with no attrition were carved in wax and later molded with alginate. These molds were filled with plaster, dental stone and/or cold-cured acrylic resin. The large individual dental stone tooth models were mounted on a wax base, thus obtaining maxillary and mandibular arches which were occluded. These dental arches were molded with plaster or dental stone. The authors suggest that these types of macro models allow an excellent visualization of the morphologic characteristics of permanent teeth and occlusion. Dental students are able to carve the permanent dentition in wax with great facility when they can observe macro models.

  5. Effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition

    OpenAIRE

    Chen, Xiaoxian; Xia, Bin; Ge, Lihong

    2015-01-01

    Background Early transition from breastfeeding and non-nutritive sucking habits may be related to occlusofacial abnormalities as environmental factors. Previous studies have not taken into account the potential for interactions between feeding practice, non-nutritive sucking habits and occlusal traits. This study assessed the effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition in 3–6-year-old childre...

  6. Van der Woude syndrome: Management in the mixed dentition

    Directory of Open Access Journals (Sweden)

    Sonahita Agarwal

    2013-01-01

    Full Text Available This article presents the case of a patient with Van der Woude syndrome treated with orthodontic and orthopedic intervention in the mixed dentition stage. The patient had a bilateral cleft of the lip and alveolus accompanied by lip pits on the lower lip. Intra-orally, there was bilateral anterior and posterior cross-bite with a collapsed maxilla. The maxillary transverse deficiency was managed with orthopedic expansion and the second phase of treatment involved secondary alveolar bone grafting followed by retention with functional regulator-3. The mild maxillary retrognathia and deficient lip support was managed with dental compensation.

  7. Validity of Moyers Mixed Dentition Analysis and a New Proposed Regression Equation as a Predictor of Width of Unerupted Canine and Premolars in Children.

    Science.gov (United States)

    Thimmegowda, Umapathy; Sarvesh, Swetha G; Shashikumar, Hassan Channaveerappa; Kanchiswamy, Lokesh Nagamangala; Shivananda, Dharmesh Hampapura; Prabhakar, Ashwini Chikkanayakanahalli

    2015-08-01

    The Moyer's mixed dentition analysis forms an essential part of diagnostic procedures to determine adequacy of the space available for the erupting permanent teeth. However, its reliability among different racial groups has been questioned. The objectives of this study were to test the reliability of Moyer's method and to produce new regression equation for Bangalore population for predicting the mesiodistal diameters of the unerupted permanent canines and premolars. Data was collected from study models of 400 randomly selected Bangalore subjects aged 13 to 16 years with fully erupted, intact dentitions and no significant malocclusion. The mesiodistal widths of the incisors, canines and premolars of both arches were measured. This data was then utilized to predict the mesiodistal widths of canines and premolars and further compared with Moyer's table. It was found that 50% is more applicable to boys and 75% to girls. The canine premolar segment in both arches is statistically larger in men than in women (p<0.05). New regression equation was formulated, the accuracy of which needs to be evaluated further in a larger sample.

  8. Roentgenographic study on maxillofacial soft tissue in the mixed dentition

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jai Hei; Ahn, Hyung Kyu [Department of Dental Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1977-11-15

    The purpose of this study was to obtain the cephalometric maxillofacial soft tissue measurements and to define the differences that exist between male and female on the soft tissue profile who had normal occlusion in mixed dentitions. For the object of this study, cephalometric radiographs were obtained from the centric occlusion with the relaxed lip position. Copper filter was designed to obtain both hard and soft tissue structure on the same film. The subjects consist of 100 male and 100 female from 8 to 12.4 years with the normal occlusion and acceptable profiles. The author measured facial depth, vertical height from the cephalometric soft tissue profiles in the mixed dentitions. The significant test was performed to compare male with females. The following results were obtained from the study 1. In facial convexity, much more larger female than that of male. 2. Inclination of the lip posture was more larger in maxilla (male) and in female more larger in the mandible. 3. The thickness of soft tissue was thicker in male, the height of nose was more prominent in female. 4. There were no significant differences in both sexes.

  9. Secular changes in tooth size and dental arch dimensions in the mixed dentition.

    Science.gov (United States)

    Lindsten, Rune

    2003-01-01

    Secular changes in the mixed dentition were studied. Permanent tooth size and dental arch dimensions were examined in Norwegian children born in the 1960s and 1980s, Swedish children born in the 1960s and 1980s, Norwegian Sami children born in the 1980s, and a sample of Norwegian skulls dating from the 14th to the 19th century. The Norwegian Sami children were nomadic in the summertime. A sample of pigs was studied before and after a maceration process to determine what dimensional changes might occur in such a process. A shrinkage of 0.3%-1.7% was found. This information was used when the skulls were compared with the modern groups. Lateral dental arch lengths were shorter in the children born in the 1960s compared with the children born in the 1980s. This was a result of the higher prevalence of caries in the second deciduous molars in the 1960s groups. Children who had lost a deciduous canine prematurely were found to have smaller dental arch perimeters. When compared with other data, this was blamed on a pre-existing crowding. Permanent tooth size was smaller in the skulls compared with the modern groups. Improved nutrition is considered to be the main reason for the difference. Relative dental arch space differed in the group born in the 1960s from that in the other groups, indicating a greater prevalence of crowding in the former. Relative dental arch space in the skulls and in the group born in the 1980s was similar. A more traditional way of living, as practised by the Sami group in this thesis, was not favorable for relative dental arch space. The transverse intermaxillary relation in boys changed from the 1960s to the 1980s, which indicated that the 1980s group ran a greater risk of developing a posterior cross-bite. Before the same conclusion could be made in the girls, the mesial drift of the first permanent molars had to be corrected for, because of a higher prevalence of caries in the 1960s group. The sex-pooled analysis of the skulls and the

  10. Permanences GAG-EPA

    CERN Multimedia

    GAC-EPA

    2015-01-01

    Le GAC organise chaque mois des permanences avec entretiens individuels. La prochaine permanence se tiendra le : Mardi 5 mai de 13 h 30 à 16 h 00 Salle de réunion de l’Association du personnel Les permanences suivantes auront lieu les mardis 2 juin, 1er septembre, 6 octobre, 3 novembre et 1er décembre 2015. Les permanences du Groupement des Anciens sont ouvertes aux bénéficiaires de la Caisse de pensions (y compris les conjoints survivants) et à tous ceux qui approchent de la retraite. Nous invitons vivement ces derniers à s’associer à notre groupement en se procurant, auprès de l’Association du personnel, les documents nécessaires.

  11. Stage-specific differential gene expression profiling and functional network analysis during morphogenesis of diphyodont dentition in miniature pigs, Sus Scrofa

    Science.gov (United States)

    2014-01-01

    Background Our current knowledge of tooth development derives mainly from studies in mice, which have only one set of non-replaced teeth, compared with the diphyodont dentition in humans. The miniature pig is also diphyodont, making it a valuable alternative model for understanding human tooth development and replacement. However, little is known about gene expression and function during swine odontogenesis. The goal of this study is to undertake the survey of differential gene expression profiling and functional network analysis during morphogenesis of diphyodont dentition in miniature pigs. The identification of genes related to diphyodont development should lead to a better understanding of morphogenetic patterns and the mechanisms of diphyodont replacement in large animal models and humans. Results The temporal gene expression profiles during early diphyodont development in miniature pigs were detected with the Affymetrix Porcine GeneChip. The gene expression data were further evaluated by ANOVA as well as pathway and STC analyses. A total of 2,053 genes were detected with differential expression. Several signal pathways and 151 genes were then identified through the construction of pathway and signal networks. Conclusions The gene expression profiles indicated that spatio-temporal down-regulation patterns of gene expression were predominant; while, both dynamic activation and inhibition of pathways occurred during the morphogenesis of diphyodont dentition. Our study offers a mechanistic framework for understanding dynamic gene regulation of early diphyodont development and provides a molecular basis for studying teeth development, replacement, and regeneration in miniature pigs. PMID:24498892

  12. Clinical and radiographic evaluation of early loaded narrow-diameter implants

    DEFF Research Database (Denmark)

    Maiorana, Carlo; King, Paul; Quaas, Sebastian

    2015-01-01

    OBJECTIVE: To evaluate the clinical reliability of narrow implants placed in a one-stage procedure and early loaded in the upper and lower incisor region. MATERIAL AND METHODS: This is a prospective, single-arm, multicenter study in which patients with missing natural dentition in upper lateral...... and lower incisor positions were enrolled. Eligible implants (OsseoSpeed™ TX 3.0S, DENTSPLY Implants) were of three different lengths and of 3.0 mm in diameter. One-stage surgery was performed and healing abutment connection took place. Placement of the permanent single crown took place after a 6-10 weeks...... healing period. Clinical and radiographic checks were performed at implant placement, loading, and at the 6, 12, 24, and 36 months follow-up visits. RESULTS: A total of 69 subjects with 97 implants have been included in this study. From surgery to 36 months follow-up, 5.6% of the implants showed bone loss...

  13. Applicability of Two Universally Accepted Mixed Dentition Analysis on a Sample from Southeastern Region of Andhra Pradesh, India.

    Science.gov (United States)

    Shobha, M B; Ajs, Sai; Manoj, Kmg; Srideevi, E; Sridhar, M; Pratap, Gmjs

    2016-01-01

    Most of the universally accepted mixed dentition analyses are based on the data derived from northwestern European descent. However, the accuracy of these methods when applied to different ethnic population is questionable. The present study is aimed to evaluate the applicability of Tanaka and Johnston (TJ) and Moyers (50(th) and 75(th) percentile) mixed dentition analysis in a sample from south-eastern region of Andhra Pradesh, India. Study models were prepared from a sample of 100 patients (50 males and 50 females) in the age range of 13-15 years. The mesio-distal dimension of the teeth was measured using a Digital Vernier calipers. The actual values of permanent canine and premolars on the casts were compared with the predicted values from TJ and Moyers analysis. The values derived from this study were statistically analyzed using SPSS version 17.0 (IBM, Chicago, USA). Pearson's coefficients were used to evaluate the correlations between the groups of teeth. Overestimated values were noticed in males and females of both arches with TJ equation; Males showed no significant difference at Moyers 50(th) percentile (50/100), in both the arches where as females showed higher values in mandibular arch and underestimated values in maxillary arch. At Moyers 75(th) percentile, overestimated values were noticed in males for both the arches whereas in females lesser values were observed. As the values showed significant deviation from TJ and Moyers both at 50 and 75 percentile, its applicability to the present population is limited. So, new regression equations were derived.

  14. Hypoplasia of a permanent incisor produced by primary incisor intrusion: a case report.

    Science.gov (United States)

    Altun, Ceyhan; Esenlik, Elçin; Tözüm, Tolga Fikret

    2009-04-01

    Orofacial trauma is a serious orodental and general health problem that may have medical, esthetic and psychological consequences for children and their parents. When the root of the primary tooth is close to the unerupted permanent tooth, primary tooth trauma may result in developmental disturbances and pulpal reaction in that permanent tooth. We report an unusual case in which injury to the primary dentition resulted in developmental disturbances in the crown and the calcified structures in the pulp chamber of the permanent tooth. Localized malformation of the crown and enamel hypoplasia were treated with a light-cured composite resin restoration. We also discuss the formation of pulp calcification and the need for endodontic treatment.

  15. Management of avulsed permanent maxillary central incisors during endotracheal intubation

    Directory of Open Access Journals (Sweden)

    Ritesh R Kalaskar

    2016-01-01

    Full Text Available Avulsion is serious injury that may encounter during endotracheal intubation and its management often presents a challenge. Replantation of the avulsed tooth can restore esthetic appearance and occlusal function shortly after the injury. The present article describes the management of air-dried maxillary permanent incisors that have been avulsed due to direct laryngoscopy during the induction of general anesthesia for tonsillectomy procedure. The replanted maxillary central incisors had maintained its function and esthetic for 1 year after replantation. Children in a mixed dentition phase are high-risk group children for traumatic dental injury during laryngoscopy; therefore, Anesthetic Departments should have local protocols to refer patients for dental treatment postoperatively in the event of trauma.

  16. The dentition of Abraham's people. Why Abraham left Mesopotamia.

    Science.gov (United States)

    Neiburger, E J; Cohen, M; Lieberman, J; Lieberman, M

    1998-11-01

    Ancient Mesopotamia (southern Iraq) in 2000 B.C. was the home of the biblical figure Abraham and his people. An analysis of skeletal material from cemeteries in the ancient cities of Ur (birthplace of Abraham) and Kish shows a homogeneous, short-lived population that suffered severe dental attrition (95 percent of inhabitants), periodontal disease (42 percent) and caries (two percent). Many oral congenital and neoplastic lesions were noted Skeletal (dental) evidence indicates the population suffered from extensive disease and nutritional deficiency. Of special note was a possible case of endodontic treatment. The people of Abraham had modern dentition but relatively poor dental health. It is probable that Abraham, if in truth he existed, left Mesopotamia because of the threat of famine, as evidenced by biblical record, geologic strata and dental analysis.

  17. Eruption age of permanent mandibular first molars and central incisors in the south Indian population

    Directory of Open Access Journals (Sweden)

    Gupta Rakhi

    2007-01-01

    Full Text Available Objective: The existing eruption schedules for permanent and deciduous dentition are based on studies in the Western population. Since Indians differ from Westerners racially, genetically, and environmentally, these studies fail to provide relevant guidance on the eruption schedule in the Indian population. This study aims at determining the eruption pattern of permanent mandibular molars and central incisors in the south Indian population. Materials and Methods: 10,156 apparently healthy Indian children in the age-group of 6-9 years were examined with mouth mirror and probe under adequate illumination for the status of the eruption of the permanent mandibular first molar and permanent mandibular central incisor. Pearson′s Chi-square test with Yates′ continuity correction was used to calculate the P -value for comparison of proportion between girls and boys. The values obtained in our study were compared with the standard values. The Z-test with continuity correction was used to calculate the P -value. Results: As per our study, the permanent mandibular first molars and central incisors erupted one to two years later compared to the values reported in Westerners. The earlier eruption of the permanent mandibular first molars compared to the permanent mandibular central incisors, as well as the earlier eruption of both the teeth in girls compared to boys, were in accordance with the existing literature. Conclusion: The eruption age reported by us may form a standard reference for eruption age in Indians.

  18. Successful strategies for matching one or two indirect restorations to natural dentition.

    Science.gov (United States)

    Sesemann, Michael R

    2011-01-01

    One of the most difficult and noble undertakings of a dental restorative team is to provide an indirect restoration for a compromised tooth surrounded by otherwise healthy, natural dentition. Matching one or two indirect dental restorations to adjacent healthy teeth is a herculean task for both the dentist and laboratory technician. The team must be knowledgeable of the natural dentition's characteristics to best mimic and recreate those same characteristics in a man-made restoration. Knowledge of principles in smile design, dental anatomy, color, characterization, material selection, doctor-technician communication, and clinical acumen are necessary to achieve a successful outcome when matching one or two indirect restorations to natural dentition.

  19. A digital volumetric tomography (DVT study in the mandibular molar region for miniscrew placement during mixed dentition

    Directory of Open Access Journals (Sweden)

    Mayur S. Bhattad

    2015-04-01

    Full Text Available OBJECTIVE: To assess bone thickness for miniscrew placement in the mandible during mixed dentition by using digital volumetric tomograph (DVT. MATERIAL AND METHODS: A total of 15 healthy patients aged 8-10 years old, with early exfoliated mandibular second deciduous molar, were included. DVT images of one quadrant of the mandible were obtained using Kodak extraoral imaging systems and analyzed by Kodak dental imaging software. The error of the method (EM was calculated using Dahlberg's formula. Mean and standard deviation were calculated at 6 and 8 mm from the cementoenamel junction (CEJ.Paired t-test was used to analyze the measurements. RESULTS: Buccal cortical bone thickness, mesiodistal width and buccolingual bone depth at 6 mm were found to be 1.73 + 0.41, 2.15 + 0.49 and 13.18 + 1.22 mm, respectively; while at 8 mm measurements were 2.42 + 0.34, 2.48 + 0.33 and 13.65 + 1.25 mm, respectively. EM for buccal cortical bone thickness, mesiodistal width and buccolingual bone depth was 0.58, 0.40 and 0.48, respectively. The difference in measurement at 6 and 8 mm for buccal cortical plate thickness (P 0.05. CONCLUSION: Bone thickness measurement has shown promising evidence for safe placement of miniscrews in the mandible during mixed dentition. The use of miniscrew is the best alternative, even in younger patients.

  20. Evaluation of dentofacial features of adolescents in early permanent dentition with normal occlusion using McNamara cephalometric analysis%恒牙早期正常(牙合)青少年牙颌面发育特征的X线头影测量McNamara法分析

    Institute of Scientific and Technical Information of China (English)

    陈远萍; 侯建华; 李青山; 毕长青; 李业东; 李秋; 杨峰

    2008-01-01

    目的:研究恒牙早期正常(牙合)青少年牙颌面硬组织发育情况,建立吉林省恒牙早期正常(牙合)青少年X线头影测量:McNamara分析法的正常值,为临床诊断、治疗评价提供参考.方法:选取吉林省内13~15岁正常(牙合)男性、女性青少年120名,拍摄X线头颅定位侧位片,进行X线头影测量McNamara分析.结果:13、14、15岁组有效下颌长度及14、15岁组下前面高男性明显大于女性,但13岁组上颌突距女性大于男性;与重庆地区比较,吉林省男性和女性的青少年有效上颌长度、有效下颌长度都明显大于重庆地区,而上前牙突距明显小于重庆地区;吉林省男性青少年的下前牙突距明显小于重庆地区男性.结论:不同性别恒牙早期正常(牙合)青少年x线头影测量McNamara分析法的正常值存在差异;不同地区正常(牙合)青少年颌面部发育存在差异,提示在矫正治疗时要根据各地区青少年发育的不同特点制定矫治计划.

  1. Component Analysis of Craniofacial Type of Xi'an Chinese with Class III Malocclusion in the Early Permanent Dentition%西安地区恒牙早期Ⅲ类错(牙合)颅面类型构成分析

    Institute of Scientific and Technical Information of China (English)

    陈嵘; 郭涛; 冯雪; 丁寅

    2010-01-01

    目的:分析西安地区恒牙早期Ⅲ类错(牙合)颅面类型的构成.方法:以本院正畸科2003~2008年恒牙早期Ⅲ类错牙 合患者为研究对象,采用计算机辅助X线头影测量技术,分析恒牙早期Ⅲ类患者在矢状向与垂直向的构成.结果:恒牙早期Ⅲ类错牙 合矢状向主要表现形式为双颌发育基本正常或上颌正常,下颌发育过度.垂直向主要表现为均角型.低角型、高角型差异不显著.交叉分析显示:上下颌均发育正常的均角型患者和上颌正常,下颌发育过度的均角型患者最多见;其次是上颌发育不足,下颌正常的均角型患者.结论:恒牙早期Ⅲ类错牙 合在矢状向与垂直向均表现出一定的趋势,分析与研究这类错(牙合)的构成加深了对西安地区Ⅲ类错(牙合)患者颅面类型的认识,并对临床上合理矫治提供一定的参考.

  2. Management of traumatically intruded permanent maxillary lateral incisor - Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Deepak Sharma

    2016-01-01

    Full Text Available Primary etiologic factors of trauma in the permanent dentition are bicycle accidents, sports accidents, falls, and fights. From the standpoint of therapy, anatomy, and prognosis, five different types of luxation lesions are recognized: Concussion, subluxation, extrusive luxation, lateral luxation, and intrusive luxation. Intrusive luxation is apical displacement of tooth into the alveolar bone. The tooth is driven into the socket, compressing the periodontal ligament, and commonly causes a crushing fracture of the alveolar socket. It is considered one of the most severe luxation injuries to affect permanent teeth. Intrusion injuries are often associated with severe damage to the tooth, periodontium, and pulpal tissue. The rare occurrence of this injury, 0.3–1.9% in the permanent dentition, has resulted in limited studies to support suggested treatment regimens. Clinical treatment for intrusion is especially difficult because of the severe complications accompanying it. These complications include pulp necrosis or obliteration, inflammatory root resorption, ankylosis, replacement root resorption, and loss of marginal bone support. Hence, the aim of presenting this case report of intrusive luxation is to highlight the importance of prompt care and root canal dressing and discuss the several treatments proposed to reposition the intruded teeth.

  3. Traumatic dental injuries and their association with malocclusion in the primary dentition of Irish children.

    LENUS (Irish Health Repository)

    Norton, Eimear

    2012-02-01

    This study sought to establish the prevalence of traumatic dental injuries in the primary dentition of Irish children and to investigate the relationship between dental trauma and non-nutritive sucking habits.

  4. Randomized Equivalence Trial of Intensive and Semiannual Applications of Fluoride Varnish in the Primary Dentition

    OpenAIRE

    Weinstein, P; Spiekerman, C.; Milgrom, P

    2009-01-01

    For children in the primary dentition with high caries prevalence the standard semiannual application of fluoride varnish may not be successful in preventing tooth decay. Oftentimes this population is mobile and does not receive consistent preventive care. This trial tested whether an intensive fluoride 5% sodium varnish regimen (three applications/2 weeks) applied annually has an equivalent effect on caries progression in the primary dentition compared to single applications applied semiannu...

  5. To evaluate the validity of Recurring Esthetic Dental proportion in natural dentition

    OpenAIRE

    Shilpa Shetty; Varun Pitti; C L Satish Babu; Surendra Kumar, G. P.; Jnanadev, K. R.

    2011-01-01

    Background: Different proportions are described in the literature for smile designing, such as Golden proportion, Golden percentage, Preston′s proportion, and recently, Recurring Esthetic Dental (RED) proportion. Aims and Objectives: To evaluate the existence of RED proportion in natural dentition. To determine the relative height of maxillary lateral incisor and canine occurring in natural dentition so that it can be used in any of the above proportions. Materials and Methods: Fiftee...

  6. Breastfeeding, Bottle Feeding Practices and Malocclusion in the Primary Dentition: A Systematic Review of Cohort Studies

    OpenAIRE

    Ana Paula Hermont; Martins, Carolina C; Zina, Lívia G.; Sheyla M. Auad; Paiva, Saul M; Pordeus, Isabela A

    2015-01-01

    The World Health Organization recommends exclusive breast feeding for at least six months. However, there is no scientific evidence of the benefits of breast feeding for oral health in children under primary dentition. This study aimed to search for scientific evidence regarding the following question: is bottle feeding associated with malocclusion in the primary dentition compared to children that are breastfed? An electronic search was performed in seven databases. The systematic review i...

  7. Prevalence of Functional Dentition in a Group of Mexican Adult Males.

    Science.gov (United States)

    Minaya-Sánchez, Mirna; Medina-Solís, Carlo Eduardo; Casanova-Rosado, Juan Fernando; Vallejos-Sánchez, Ana Alicia; Casanova-Rosado, Alejandro José; Márquez-Corona, María de Lourdes; Mendoza-Rodríguez, Martha; Maupomé, Gerardo

    2017-09-01

    To determine the prevalence of functional dentition and associated periodontal variables in a sample of Mexican adult males. A cross-sectional study of 161 policemen in Campeche, Mexico, was carried out. A clinical examination using an electronic probe was used to collect variables (dental plaque, periodontal pockets, gingival recession, suppuration, and bleeding on probing) on 6 periodontal sites (a maximum of 168 sites, excluding third molars). Sociodemographic, socioeconomic, and behavioral variables were collected through a self-administered survey. Functional dentition was defined as having 21 or more natural teeth. Data were analyzed with STATA 11.0, using logistic regression models. Mean age was 38.3 (±10.9) years. The prevalence of having a functional dentition was 83.8% in the sample. The odds of having a functional dentition declined with age (odds ratio [OR] = 0.93), having diabetes (OR = 0.27) and with having a high percentage of sites with plaque (OR = 0.77), with bleeding on probing (OR = 0.97), and with gingival recession (OR = 0.82). While a large proportion of subjects had a functional dentition in this community-dwelling sample of adult Mexican males, the likelihood of their having a functional dentition decreased with age, with their having been diagnosed with diabetes, and with assorted negative indicators of periodontal/gingival status.

  8. Influence of the banded Herbst appliance on dental changes in mixed dentition

    Directory of Open Access Journals (Sweden)

    Luana Paz Sampaio

    2012-02-01

    Full Text Available OBJECTIVE: This prospective clinical study was conducted with the purpose of evaluating the influence of the banded Herbst appliance on dental changes during the early treatment of Class II malocclusion. METHOD: The sample consisted of 15 prepubertal subjects (12 boys and 3 girls, initial age: 9 years and 6 months who were treated with the Herbst appliance. Treatment effects were compared with those of a Class II Division 1 group of 15 subjects (8 boys and 7 girls, mean initial age 9 years and 1 month, not treated orthodontically. Statistical analysis was performed using Student t-test with 5% significance level. RESULTS: The results showed that treatment with the banded Herbst appliance in the mixed dentition stage tended to upright maxillary incisors (mean: 4.14°. The maxillary molars were distalized and intruded significantly (mean 2.65 mm and 1.24 mm, respectively, the lower incisors slightly protruded anteriorly (mean 1.64 mm and the molars showed no significant changes in the horizontal and vertical directions. Furthermore, significant improvements were noted in overbite (1.26 mm, overjet (4.8 mm and molar relationship (12.08 mm. CONCLUSIONS: Changes in the upper dental arch were found to be greater than changes in the lower arch. Furthermore, mandibular anchorage loss was reduced due to the anchorage system used in the study.

  9. [Influence of feeding patterns on the development of teeth, dentition and jaw in children].

    Science.gov (United States)

    Wang, Xiao-tong; Ge, Li-hong

    2015-02-18

    Breastfeeding has been recognized as the most natural and nutritious way of feeding babies. Besides the nutritional, immunological and emotional benefits, breastfeeding promotes a healthy stomatognathic system. First of all, the nutrients and minerals in maternal milk are easy to be absorbed by the infants, which contributes to the mineralization of the teeth, and suppress the propagation of bacteria on the teeth. Though the jury is still out on whether breastfeeding can prevent Early Childhood Caries (ECC), it is definite that we should pay attention to feeding at night and the oral hygiene of the babies. Secondly, the method of feeding is closely bound up with the development of dentition and jaw. Breast- and bottle-feeding involve different orofacial muscles, which possibly have different effects on the harmonic growth of maxilla and dental arches. Meanwhile, breathing, swallowing and mastication should be developing in harmony, and differences exist in the learning of the coordinated movement between breast feeding and bottle feeding children. Bottle feeding had been proved to be closely related with the non-nutritive sucking habits which can cause malocclusion. At last, it should be pointed out that breast feeding should be the only feeding source in the first 6 months of life, then supplementary foods should be added. And prolonged bottle feeding should be avoided. We can see that breast feeding is definitely good for the infants, but the reality is not optimistic in our country.

  10. Caries experience in the primary dentition and presence of plaque in 7-year-old Chinese children: A 4-year time-lag study.

    Science.gov (United States)

    Hu, Xuan; Fan, Mingwen; Mulder, Jan; Frencken, J E

    2015-01-01

    The aim of the present study was to test the hypothesis that dental caries prevalence and caries experience in primary dentitions has increased over 4 years and to compare the presence of plaque on permanent teeth in child cohorts over 4 years. A time-lag study design was used comprising two cohorts of children aged 7 years from the same five primary schools in Wuhan examined in 2007 and 2011. Two calibrated examiners visually assessed plaque accumulation according to the Greene and Vermillion Index and the dentitions according to the Atraumatic Restorative Treatment (ART) caries criteria. Analysis of variance (ANOVA), logistic regression, and Chi-square test were used to test for differences between dependent and independent variables. The 2007 sample consisted of 817 children and the 2011 sample consisted of 1010 children. The prevalence of dental caries (d3mft) was 68.2% in 2007 and 67.7% in 2011, while that of d2mft was 78.5% in 2007 and 71.4% in 2011 (P educational authorities should collaborate in setting up programs aimed at ensuring good oral health for school children.

  11. Permanent magnet design methodology

    Science.gov (United States)

    Leupold, Herbert A.

    1991-01-01

    Design techniques developed for the exploitation of high energy magnetically rigid materials such as Sm-Co and Nd-Fe-B have resulted in a revolution in kind rather than in degree in the design of a variety of electron guidance structures for ballistic and aerospace applications. Salient examples are listed. Several prototype models were developed. These structures are discussed in some detail: permanent magnet solenoids, transverse field sources, periodic structures, and very high field structures.

  12. The use of the Jasper Jumper for the correction of Class II malocclusion in the young permanent dentition

    OpenAIRE

    Stucki, N.; Ingervall, B.

    2017-01-01

    The effect of the Jasper Jumper in the treatment of Class II, division 1 malocclusions was studied in 26 consecutive 13-25-year-old patients. The median treatment time was 5 months, followed by a median period of observation or retention of 7 months. The effects of the treatment were evaluated from cephalograms taken before the treatment, at the removal of the Jumpers and at the end of the period of observation or retention. The Jumpers brought about a slight retrusion of the maxilla and mark...

  13. An Interdisciplinary Approach in Rehabilitation of an Adult Mutilated Dentition with Multiple Missing Permanent Teeth--A Case Report.

    Science.gov (United States)

    Agrawal, Sarvesh; Jose, Nidhin Philip; Bandi, Rohan S; Jain, Nimit; Rodrigues, Shobha J

    2015-01-01

    Adult orthodontics has been an area of increasing focus in recent times. Comprehensive treatment of adults is more challenging due to a myriad of problems that coexist in an adult that makes treatment planning more challenging. A large number of individuals seek dental care because of aesthetic reasons, that is, the desire to look more attractive by improving their smiles. The role an attractive smile plays on a person's self-image and confidence cannot be overemphasized. Evaluating and treating patients for the purpose of smile design often involves a multi-discipline approach. Achieving an ideal smile may require orthodontics, orthognathic surgery, periodontal therapy, including soft tissue repositioning and bone re-contouring, cosmetic dentistry, and plastic surgery. This aesthetic approach to patient care produces the best dental and dental-facial beauty. This paper describes a case report in which an orthodontist, an endodontist, and a prosthodontist worked as a team to improve the patients smile and confidence.

  14. Lawful Permanent Residents - Annual Report

    Data.gov (United States)

    Department of Homeland Security — A lawful permanent resident (LPR) or 'green card' recipient is defined by immigration law as a person who has been granted lawful permanent residence in the United...

  15. Treatment of Class II open bite in the mixed dentition with a removable functional appliance and headgear.

    Science.gov (United States)

    Ngan, P; Wilson, S; Florman, M; Wei, S H

    1992-05-01

    Early diagnosis of patients exhibiting open bites that are complicated by skeletal Class II and vertical growth problems can facilitate subsequent treatment. Eight patients with Class II skeletal open bite were treated with the high-pull activator appliance and compared to reasonably matched controls to determine the effects of the appliance. The high-pull activator was found to reduce forward growth of the maxilla and increase mandibular alveolar height, transforming the Class II molar relationship into a Class I molar relationship. The overjet and open bite were decreased, and, in addition, the appliance reduced the amount of forward and downward movement of the maxillary molars, providing vertical control of the maxilla during Class II orthopedic correction. These results demonstrated that open bite complicated by a Class II vertical growth pattern can be treated during the mixed dentition with favorable results by a combination of a removable functional appliance and high-pull headgear.

  16. [Ready-made crowns in the deciduous dentition].

    Science.gov (United States)

    Schulte, A

    1999-01-01

    The following review of the literature on "prefabricated crowns for deciduous teeth" attempts to highlight the benefits and limitations of this treatment modality. The use of prefabricated crowns is indicated in the following situations: severe destruction of the clinical crown, deep approximal cavities, bilateral approximal cavities, circumferential caries, history of root canal treatment, and need for fixed space retention. Compared to amalgam restorations involving two or more surfaces, prefabricated crowns on deciduous molar teeth gave very high survival rates. They consist of a chromium-nickel-steel alloy and are reported to have an acceptable gingival tolerance profile. In contrast to the Anglo-American countries this treatment modality is quite uncommon in Germany. A probable reason for this reservation could be that many clinicians often fail to see the need for a filling in the deciduous dentition. Besides, many dentists are reluctant to use local anesthesia in children, which is inevitable in preparing and fitting a prefabricated crown. In the United States and UK dentists are less frequently confronted with this problem, as complex treatments are often carried out under nitrous oxide sedation or insufflation anesthesia. Modern filling materials have been introduced which have the potential to narrow the indications for prefabricated stainless steel crowns. Against this background, future studies are necessary to compare the survival rates of prefabricated crowns and modern filling materials.

  17. Imaging the zebrafish dentition: from traditional approaches to emerging technologies.

    Science.gov (United States)

    Bruneel, Bart; Mathä, Markus; Paesen, Rik; Ameloot, Marcel; Weninger, Wolfgang J; Huysseune, Ann

    2015-02-01

    The zebrafish, a model organism for which a plethora of molecular and genetic techniques exists, has a lifelong replacing dentition of 22 pharyngeal teeth. This is in contrast to the mouse, which is the key organism in dental research but whose teeth are never replaced. Employing the zebrafish as the main organism to elucidate the mechanisms of continuous tooth replacement, however, poses at least one major problem, related to the fact that all teeth are located deep inside the body. Investigating tooth replacement thus relies on conventional histological methods, which are often laborious, time-consuming and can cause tissue deformations. In this review, we investigate the advantages and limitations of adapting current visualization techniques to dental research in zebrafish. We discuss techniques for fast sectioning, such as vibratome sectioning and high-resolution episcopic microscopy, and methods for in toto visualization, such as Alizarin red staining, micro-computed tomography, and optical projection tomography. Techniques for in vivo imaging, such as two-photon excitation fluorescence and second harmonic generation microscopy, are also covered. Finally, the possibilities of light sheet microscopy are addressed.

  18. [Prevalence of temporomandibular disorders in Mexican children with mixed dentition].

    Science.gov (United States)

    Ramírez-Caro, Silvia N; Espinosa de Santillana, Irene A; Muñoz-Quintana, Gabriel

    2015-04-01

    Objective To determine and compare with reports in the bibliography, the prevalence of temporomandibular disorders with an instrument validated for Mexican children with mixed dentition. Methods 150 children, from 8 to 12 years of age and of any sex who attended the pediatric stomatology clinic of the BUAP (Meritorious Autonomous University of Puebla) were included and evaluated with the diagnostic criteria for research on TTM (CDI/TTM) by a researcher who had been previously standardized (kappa=0.93). The results contrasted with reports in the bibliography. Results The prevalence of TTM was 20.7%. It was predominantly muscular (77.4%), though 33.3% showed alteration of the mouth-opening pattern, 34% showed joint noises (clicks). The most compromised mandibular function was chewing (6%). These results contrast with reports in the bibliography, specifically in terms of muscle pain sites and headaches, probably explained by different instruments used. Conclusion The prevalence of TTM is in contrast among different studies. It is necessary to place emphasis on the need to evaluate these factors during the childhood and adolescence with validated instruments.

  19. Incidence of oral habits in children with mixed dentition.

    Science.gov (United States)

    Bosnjak, Andrija; Vućićević-Boras, Vanja; Miletić, Ivana; Bozić, Darko; Vukelja, Milko

    2002-09-01

    Recognition and elimination of an oral habit is of utmost importance in the treatment of periodontal disease. It is not probable that the influence of such a factor can lead to the alteration of gingival dimension, but a cofactor role of oral habits in the development of gingival recession has been acclaimed. The purpose of this study was to present cross-sectional data from an epidemiological study performed in two urban settlements in Zagreb, Croatia. The study was performed in 1025 children, in an attempt to try and discover the incidence of oral habits in children with mixed dentition, aged from 6 to 11 years. About 33.37% of the screened population exhibited oral habits, such as nail and object biting, non-nutritive sucking, simple tongue thrusting and lip or cheek biting. Chi-square test analysis showed no statistically significant differences between sex and age groups, a result that does not exclude the oral habits from aetiology of the periodontal pathology. We can conclude that oral habits are a frequent finding, although the cause relation to periodontitis has yet to be cleared completely.

  20. The prevalence of temporomandibular joint dysfunction in the mixed dentition.

    Science.gov (United States)

    Tuerlings, Virginie; Limme, Michel

    2004-06-01

    A functional and articular examination was carried out of 136 children (70 boys, 66 girls) aged from 6 to 12 years (6 years 1 month to 12 years 9 months), all presenting with a malocclusion in the mixed dentition and who had not yet received orthodontic treatment. The aim of the study was to examine the prevalence of signs of temporomandibular joint dysfunction (TMD) in this population and to evaluate the possible relationship between certain 'individual' parameters and TMD signs. The results showed an elevated prevalence of muscle tenderness, particularly in the lateral pterygoid muscle, which was found to be sensitive in 80.9 per cent of patients. Muscle tenderness had a tendency to increase with age and was greater on the right side. Temporomandibular joint sounds were present in 35.3 per cent of the subjects and more frequent in girls and in older children. Of the children who presented a mandibular deviation on maximal opening (19.8 per cent), 13.2 per cent had a predominance of opening deviation towards the left. Retruded contact position interferences were present in 57.4 per cent of the children and 72.1 per cent presented lateral and protrusive interferences. Assessment of the maximal amplitudes of mandibular movements did not reveal any limitations. These results indicate that few relationships exist between individual parameters and TMD signs.

  1. Development and evolution of dentition pattern and tooth order in the skates and rays (batoidea; chondrichthyes.

    Directory of Open Access Journals (Sweden)

    Charlie J Underwood

    Full Text Available Shark and ray (elasmobranch dentitions are well known for their multiple generations of teeth, with isolated teeth being common in the fossil record. However, how the diverse dentitions characteristic of elasmobranchs form is still poorly understood. Data on the development and maintenance of the dental patterning in this major vertebrate group will allow comparisons to other morphologically diverse taxa, including the bony fishes, in order to identify shared pattern characters for the vertebrate dentition as a whole. Data is especially lacking from the Batoidea (skates and rays, hence our objective is to compile data on embryonic and adult batoid tooth development contributing to ordering of the dentition, from cleared and stained specimens and micro-CT scans, with 3D rendered models. We selected species (adult and embryonic spanning phylogenetically significant batoid clades, such that our observations may raise questions about relationships within the batoids, particularly with respect to current molecular-based analyses. We include developmental data from embryos of recent model organisms Leucoraja erinacea and Raja clavata to evaluate the earliest establishment of the dentition. Characters of the batoid dentition investigated include alternate addition of teeth as offset successional tooth rows (versus single separate files, presence of a symphyseal initiator region (symphyseal tooth present, or absent, but with two parasymphyseal teeth and a restriction to tooth addition along each jaw reducing the number of tooth families, relative to addition of successor teeth within each family. Our ultimate aim is to understand the shared characters of the batoids, and whether or not these dental characters are shared more broadly within elasmobranchs, by comparing these to dentitions in shark outgroups. These developmental morphological analyses will provide a solid basis to better understand dental evolution in these important vertebrate groups as

  2. Development and evolution of dentition pattern and tooth order in the skates and rays (batoidea; chondrichthyes).

    Science.gov (United States)

    Underwood, Charlie J; Johanson, Zerina; Welten, Monique; Metscher, Brian; Rasch, Liam J; Fraser, Gareth J; Smith, Moya Meredith

    2015-01-01

    Shark and ray (elasmobranch) dentitions are well known for their multiple generations of teeth, with isolated teeth being common in the fossil record. However, how the diverse dentitions characteristic of elasmobranchs form is still poorly understood. Data on the development and maintenance of the dental patterning in this major vertebrate group will allow comparisons to other morphologically diverse taxa, including the bony fishes, in order to identify shared pattern characters for the vertebrate dentition as a whole. Data is especially lacking from the Batoidea (skates and rays), hence our objective is to compile data on embryonic and adult batoid tooth development contributing to ordering of the dentition, from cleared and stained specimens and micro-CT scans, with 3D rendered models. We selected species (adult and embryonic) spanning phylogenetically significant batoid clades, such that our observations may raise questions about relationships within the batoids, particularly with respect to current molecular-based analyses. We include developmental data from embryos of recent model organisms Leucoraja erinacea and Raja clavata to evaluate the earliest establishment of the dentition. Characters of the batoid dentition investigated include alternate addition of teeth as offset successional tooth rows (versus single separate files), presence of a symphyseal initiator region (symphyseal tooth present, or absent, but with two parasymphyseal teeth) and a restriction to tooth addition along each jaw reducing the number of tooth families, relative to addition of successor teeth within each family. Our ultimate aim is to understand the shared characters of the batoids, and whether or not these dental characters are shared more broadly within elasmobranchs, by comparing these to dentitions in shark outgroups. These developmental morphological analyses will provide a solid basis to better understand dental evolution in these important vertebrate groups as well as the

  3. Early

    Directory of Open Access Journals (Sweden)

    Kamel Abd Elaziz Mohamed

    2014-04-01

    Conclusion: Early PDT is recommended for patients who require prolonged tracheal intubation in the ICU as outcomes like the duration of mechanical ventilation length of ICU stay and hospital stay were significantly shorter in early tracheostomy.

  4. Permanence can be Defended.

    Science.gov (United States)

    McGee, Andrew; Gardiner, Dale

    2017-03-01

    In donation after the circulatory-respiratory determination of death (DCDD), the dead donor rule requires that the donor be dead before organ procurement can proceed. Under the relevant limb of the Uniform Determination of Death Act 1981 (USA), a person is dead when the cessation of circulatory-respiratory function is 'irreversible'. Critics of current practice in DCDD have argued that the donor is not dead at the time organs are procured, and so the procurement of organs from these donors violates the dead donor rule. We offer a new argument here in defence of current DCDD practice, and, in particular, of the interpretation of the requirement of 'irreversibility' as permanence.

  5. Pulsars: Cosmic Permanent 'Neutromagnets'?

    CERN Document Server

    Hansson, Johan

    2011-01-01

    We argue that pulsars may be spin-polarized neutron stars, i.e. cosmic permanent magnets. This would simply explain several observational facts about pulsars, including the 'beacon effect' itself i.e. the static/stable misalignment of rotational and magnetic axes, the extreme temporal stability of the pulses and the existence of an upper limit for the magnetic field strength - coinciding with the one observed in "magnetars". Although our model admittedly is speculative, this latter fact seems to us unlikely to be pure coincidence.

  6. "Electromyographic pattern of masticatory muscles in altered dentition" Part II

    Directory of Open Access Journals (Sweden)

    H D Adhikari

    2011-01-01

    Full Text Available Aim : The aim of this study is to show that a change in occlusal contacting pattern of tooth has definite influence over the behavior of orofacial musculature, resulting deleterious effect on it. Keeping this in view, the electromyographic (EMG activity of temporalis and masseter muscles in rest position of mandible, maximum clenching and chewing, was studied in total 24 subjects--14 subjects with normal occlusion and rest 10 with normal occlusion and one tooth carious which was prepared to receive an inlay with high point. This high point or occlusal interference was introduced intentionally to have a change in occlusion or "altered dentition". The subjects were all male medical volunteers with average age group of 20 years. A particular variety of chewing substance - chewing gum was used in this study. No EMG activity was detected in the rest position of mandible. In maximum clenching, balanced type of activity was seen bilaterally in normal occlusion.Whereas in changed occlusion, an unbalanced type of muscle activity was seen in temporalis muscle during maximum clenching. There was an overall decrease in activity in both the muscles during maximum clenching and during chewing. This decrease in activity was statistically significant in most of the times. A non-specific pattern of muscle activity resembling spasm in skeletal muscle -- a state of "hyperactivity" was also found during chewing in presence of occlusal interference. This spasm-like activity may cause pain in the muscles of masticatory apparatus. All these abnormal types of behavior of muscle were abolished after removal of high point and establishing the previous normal occlusion. It is therefore, for the clinicians to understand the importance of establishing occlusal equilibrium in day to day practice.

  7. Asymmetry of mandibular dentition is associated with dietary specialization in snail-eating snakes

    Science.gov (United States)

    2017-01-01

    Background In vertebrates, the left-and-right pairs of homologous organs are generally present in equal numbers. A remarkable exception is snail-eating snakes in the family Pareidae: almost all the pareid snakes have much more teeth on the right mandible than on the left for functional specialization in feeding on the dextral majority of land snails. Because the only exceptional species with symmetric dentition has been regarded as a slug-eater, the extent of dietary specialization on slugs could shape the degree of the lateral asymmetry of mandibular dentition (dentition asymmetry) even among snail eaters. Methods To test this, I compared the morphology and behavior of two sympatric species of Taiwanese snail-eating snakes, Pareas atayal and P. formosensis. Results Specimens collected in the same locality showed that the dentition asymmetry of P. formosensis was significantly smaller than that of P. atayal. Congruent to its weak asymmetry, P. formosensis showed a strong preference of slugs to snails in the feeding experiment. Discussion The dietary specialization of P. formosensis on slugs would contribute to niche partitioning from the sympatric congener P. atayal. This study suggests that the diverse variation in the dentition asymmetry of pareid snakes is the result of their dietary specialization and divergence. PMID:28265502

  8. Revascularization of an impacted, immature dilacerated permanent maxillary central incisor associated with odontoma and a supernumerary tooth

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2013-01-01

    Full Text Available To intentionally replant an impacted immature permanent maxillary central incisor in the mixed dentition period followed by revascularization in order to achieve apical root closure. A 9-year-old boy presented with retained maxillary left primary incisors. Radiographic evaluation revealed the presence of a supernumerary tooth and an odontoma associated with an impacted permanent maxillary left central incisor, having root dilaceration. Treatment included surgical removal of mesiodens and odontoma. The impacted dilacerated permanent central incisor was removed and intentionally replanted, followed by revascularization of pulp. During the follow-up, root end closure with narrowing of canal space was observed, patient has been asymptomatic and the tooth remains vital. Revascularization of the immature reimplanted tooth showed continued root development and thickening of the lateral dentinal walls through deposition of new hard tissue and narrowing of the canal space.

  9. Reliability of permanent mandibular first molars and incisors widths as predictor for the width of permanent mandibular and maxillary canines and premolars

    Directory of Open Access Journals (Sweden)

    Madhulika Mittar

    2012-01-01

    Full Text Available Aim: Preventive measures are necessary to prevent a potential irregularity from progressing into a more severe malocclusion. The determination of the tooth size-arch length discrepancy in mixed dentition requires an accurate prediction of the mesiodistal widths of the unerupted permanent teeth. Materials and Methods: For the study, 200 subjects in the age group of 16-25 years were selected from various colleges of M. M. University. The mesiodistal width of permanent mandibular incisors, first molars, canines and premolars of both arches were measured on the subject cast using an electronic digital caliper. Statistical analysis showed a significant difference between mesiodistal tooth widths of males and females. Linear regression equation was determined to predict the sum of mandibular and maxillary permanent canines and premolars using mandibular first molars plus the four mandibular incisors as predictors. Results: There was no significant difference between the actual and predicted width of sum of permanent canines and premolars using regression equations. The predicted widths of both arches using Tanaka and Johnston equations showed significant differences. Determined regression equations for males were accurate in male samples and determined regression equation for females were accurate in female samples for both arches.

  10. Combining traditional and adhesive dentistry to reconstruct the excessively worn dentition.

    Science.gov (United States)

    Mizrahi, Basil

    2008-01-01

    Adhesive dentistry has changed the face of traditional dentistry and has the potential to improve esthetics and reduce tooth preparation. However, the materials and techniques used in adhesive dentistry are generally more technique sensitive than those used in traditional dentistry. It is, therefore, important that strict guidelines and protocols are followed to ensure long-term success. Clinicians must be able to determine where adhesive techniques and materials can be used and where traditional, biomechanically sound techniques and materials should be used. There appears to be an increasing trend of young to middle-aged patients presenting with advanced generalized tooth surface loss. These dentitions are conducive to treatment that combines traditional and adhesive materials and techniques. This article discusses guidelines for treatment of these dentitions and outlines the clinical treatment involved in the full-mouth rehabilitation of a worn dentition using a combination of all-ceramic crowns, porcelain and gold onlays, and porcelain veneers.

  11. Orthodontic Management of a Severely Rotated Maxillary Central Incisor in the Mixed Dentition: A Case Report

    Directory of Open Access Journals (Sweden)

    Arezoo Jahanbin

    2014-06-01

    Full Text Available The aim of this case report was to introduce an appliance for correcting severe rotation of anterior teeth in the mixed dentition period. A 9-year-old Iranian boy with a mixed dentition Class I malocclusion complained of a severely rotated of upper right central incisor. There was a mesiodens between the central incisors. The supernumerary tooth was first extracted and then a Whip appliance which is composed of a removable plate, a cantilever spring and a central bracket on the rotated tooth was utilized. After 8 months, the upper right central incisor was orthodontically brought into proper alignment. Circumferential supracrestal fibrotomy was performed on the overcorrected tooth. One week after surgery, the device was removed and the retention was started. The whip appliance is a removable appliance that can effectively correct severe rotation of anterior teeth especially during the mixed dentition period.

  12. Differences between dentitions with palatally and labially located maxillary canines observed in incisor width, dental morphology and space conditions

    DEFF Research Database (Denmark)

    Artmann, L; Larsen, H J; Sørensen, H B;

    2010-01-01

    To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases.......To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases....

  13. The dentition: the outcomes of morphogenesis leading to variations of tooth number, size and shape.

    Science.gov (United States)

    Brook, A H; Jernvall, J; Smith, R N; Hughes, T E; Townsend, G C

    2014-06-01

    The clinical importance of variations of tooth number, size and shape is seen in many dental disciplines. Early diagnosis allows optimal patient management and treatment planning, with intervention at an appropriate time to prevent complications in development and so reduce later treatment need. Understanding the process of dental morphogenesis and the variations in outcomes is an important contribution to the multidisciplinary clinical team approach to treatment. Tooth number, size and shape are determined during the initiation and morphogenetic stages of odontogenesis. The molecular evidence of repetitive signalling throughout initiation and morphogenesis is reflected clinically in the association of anomalies of number, size and shape. This association has been statistically modelled from epidemiological evidence and confirmed by 2D and 3D measurement of human dental study casts. In individuals with hypodontia, the teeth that are formed are smaller than the population mean and often show reduced and simplified shape. In contrast, in individuals with supernumerary teeth, the other teeth are larger than average and may show an enhanced shape. Clinical observations in humans and studies of laboratory animals gave rise to the concept of morphogenetic fields within the dentition. The findings, which can also be considered as reflecting gene expression territories, have been developed to incorporate field, clone and homeobox theories. The clinical distribution of developmental anomalies tends to follow the pattern of these fields or territories. Improved care for patients with these anomalies will come not only from utilizing a multidisciplinary clinical team but also by expanding the approach to include other relevant scientific disciplines. © 2014 Australian Dental Association.

  14. Prosthodontic management of worn dentition in pediatric patient with complete overlay dentures: a case report.

    Science.gov (United States)

    Kumar, Prince; Rastogi, Jyoti; Jain, Chandni; Singh, Harkanwal Preet

    2012-11-01

    Overlay complete dentures are simple, reversible and economical treatment modality for patients with congenital or acquired disorders that severely affect the tooth development. It satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated. In pediatric patients, the overlay dentures establish a relatively stable occlusion that improves patient's tolerance to the future treatment procedures for worn dentition. This clinical report highlights the imperative need of appropriate treatment strategy and application of maxillary and mandibular overlay dentures in a pediatric patient who suffered from congenitally mutilated and worn dentition.

  15. Full Mouth Reconstruction of a Patient with Severely Worn Dentition: A Clinical Report

    Directory of Open Access Journals (Sweden)

    Ramin Negahdari

    2016-01-01

    Full Text Available If remained untreated, progressive dental wear can lead to pulpal pathology, occlusal disharmony, and impaired function and esthetics. This case report describes prosthetic rehabilitation of a 53 year-old man with the loss of anterior guidance, severe wear of dentition and vertical dimension loss. Oral rehabilitation was performed by reconstruction of vertical dimension, crown lengthening, conventional implants, and custom cast gold post and cores as well as porcelain fused to metal restorations. Full mouth reconstruction of the patient with severely worn dentition was found to be successful after 4 years of follow up.   Keywords: mouth rehabilitation, tooth wear, vertical dimension

  16. The JP2 genotype of Aggregatibacter actinomycetemcomitans and marginal periodontitis in the mixed dentition

    DEFF Research Database (Denmark)

    Jensen, Anne Birkeholm; Ennibi, Oum Keltoum; Ismaili, Zouheir

    2016-01-01

    AIM: To perform a cross-sectional study on the carrier frequency of JP2 and non-JP2 genotypes of A. actinomycetemcomitans in Moroccan schoolchildren and relate the presence of these genotypes to the periodontal status in the mixed dentition. MATERIAL AND METHODS: A plaque sample from 513 children...... the JP2 genotype and 186 (36.3%) were positive for non-JP2 genotypes, whereas A. actinomycetemcomitans could not be detected in the remaining 281 subjects. Among 75 subjects with mixed dentition and selected for clinical examination, clinical attachment loss (CAL) ≥3 mm at two or more periodontal sites...

  17. The JP2 genotype of Aggregatibacter actinomycetemcomitans and marginal periodontitis in the mixed dentition

    DEFF Research Database (Denmark)

    Jensen, Anne Birkeholm; Ennibi, Oum Keltoum; Ismaili, Zouheir

    2016-01-01

    AIM: To perform a cross-sectional study on the carrier frequency of JP2 and non-JP2 genotypes of A. actinomycetemcomitans in Moroccan schoolchildren and relate the presence of these genotypes to the periodontal status in the mixed dentition. MATERIAL AND METHODS: A plaque sample from 513 children...... the JP2 genotype and 186 (36.3%) were positive for non-JP2 genotypes, whereas A. actinomycetemcomitans could not be detected in the remaining 281 subjects. Among 75 subjects with mixed dentition and selected for clinical examination, clinical attachment loss (CAL) ≥3 mm at two or more periodontal sites...

  18. Full mouth rehabilitation of destroyed dentition with rotational path removable partial denture: a case report.

    Science.gov (United States)

    Kim, Moon-Hyoung; Heo, Seong-Joo; Kim, Seong-Kyun; Koak, Jai-Young

    2010-06-01

    Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure.

  19. Use of Zirconia to Restore Severely Worn Dentition: A Case Report

    Directory of Open Access Journals (Sweden)

    Manish Agrawal

    2012-01-01

    Full Text Available The management of tooth wear has been a subject of increasing interest from both preventive and restorative points of view. Severe tooth wear is frequently multifactorial and variable. Successful management is a subject of interest in dentistry. A critical aspect is to determine the occlusal vertical dimension (OVD and a systematic approach that can lead to a predictable and favorable treatment prognosis. Management of patients with worn dentition is complex and difficult. Accurate clinical and radiographic examinations, a diagnostic wax-up, and determining OVD are crucial. This paper describes the full-mouth rehabilitation of a 47-year-old bruxer with a severely worn dentition.

  20. Permanent deformation of asphalt mixes

    NARCIS (Netherlands)

    Muraya, P.M.

    2007-01-01

    This dissertation describes the results of a research that was conducted on the permanent deformation of asphalt mixtures. Central to this research was the separate characterization of the contribution of the aggregate skeleton and the bituminous mortar towards resistance to permanent deformation. T

  1. Permanent-Magnet Meissner Bearing

    Science.gov (United States)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  2. The "Permanent" Patient Problem.

    Science.gov (United States)

    Bruce, Courtenay R; Majumder, Mary A

    2014-01-01

    Patients who enter the health care system for acute care may become "permanent" patients of the hospital when a lack of resources precludes discharge to the next level of post-acute care. Legal, professional, and ethical norms prohibit physician and acute care hospital "dumping" of these patients. However, limitless use of hospital resources for indefinite stays is untenable. In the absence of hospital policy addressing this specific issue, the availability of financial support will be determined by health care professionals' willingness to advocate for the patient and negotiate with hospital administrators and the ability and willingness of administrators to authorize the use of hospital resources. We propose five mid-level ethical principles to guide advocacy and administrative decision-making about provision of financial support for post-acute care for those patients who cannot afford it. We use two actual, de-identified cases to illustrate how these principles can be used to make reasoned, consistent decisions about the provision of post-acute financial support.

  3. Early treatment of Class III malocclusion with a tandem traction bow appliance

    OpenAIRE

    Sneha Basaveshwar Valgadde; Kishor Chougule

    2016-01-01

    Since Class III malocclusion is progressive in nature, the facial growth of Class III malocclusion worsens with age. Class III malocclusion is associated with a deviation in the sagittal relationship of the maxilla and the mandible, characterized by a deficient maxilla, retrognathic mandible, or a combination of both. The early orthopedic treatment of Class III malocclusions, at the end of primary dentition or the beginning of mixed dentition, prior to growth spurt, allows the accomplishment ...

  4. Curvature morphology of the mandibular dentition and the development of concave-convex vertical stripping instruments.

    Science.gov (United States)

    Ihlow, Dankmar; Kubein-Meesenburg, Dietmar; Hunze, Justus; Dathe, Henning; Planert, Jens; Schwestka-Polly, Rainer; Nägerl, Hans

    2002-07-01

    Radii for concave-convex vertical stripping instruments can be derived from measurements of the natural curvature morphology in the horizontal contact area of the mandibular dentition. The concave-convex adjustment of contacts in the anterior dental arch with a newly developed set of concave-convex stripping instruments should enable orthodontic crowding problems to be alleviated biomechanically.

  5. To evaluate the validity of Recurring Esthetic Dental proportion in natural dentition.

    Science.gov (United States)

    Shetty, Shilpa; Pitti, Varun; Satish Babu, Cl; Surendra Kumar, Gp; Jnanadev, Kr

    2011-07-01

    Different proportions are described in the literature for smile designing, such as Golden proportion, Golden percentage, Preston's proportion, and recently, Recurring Esthetic Dental (RED) proportion. To evaluate the existence of RED proportion in natural dentition. To determine the relative height of maxillary lateral incisor and canine occurring in natural dentition so that it can be used in any of the above proportions. Fifteen male subjects and 15 female subjects in each of the different age groups of 18-23 years, 24-29 years and 30-35 years were selected for this study (total 90). Photographs of the subjects were taken using Nikon D200 camera with 135 mm lens and analyzed using Adobe Photoshop CS4 extended software. The height and width of maxillary central incisors, lateral incisors and canines were found out using the measuring tool provided in the software. Average width ratio and height ratio of maxillary lateral incisor to central incisor and maxillary canine to lateral incisor were calculated to check the existence of RED proportion in natural dentition. Average lateral incisor to central incisor height ratio for "small"- and "medium"-sized teeth was found to be 88% and for "tall"-sized teeth was found to be 84%. Average canine to lateral incisor height ratio for "small"- and "medium"-sized teeth was found to be 106% and for "tall"-sized teeth was found to be 105%. Within the limitations of the study, RED proportion was not seen in natural dentition.

  6. Finite-element analysis of the center of resistance of the mandibular dentition

    Science.gov (United States)

    Jo, A-Ra; Lee, Kee-Joon; Sung, Sang-Jin; Chun, Youn-Sic

    2017-01-01

    Objective The aim of this study was to investigate the three-dimensional (3D) position of the center of resistance of 4 mandibular anterior teeth, 6 mandibular anterior teeth, and the complete mandibular dentition by using 3D finite-element analysis. Methods Finite-element models included the complete mandibular dentition, periodontal ligament, and alveolar bone. The crowns of teeth in each group were fixed with buccal and lingual arch wires and lingual splint wires to minimize individual tooth movement and to evenly disperse the forces onto the teeth. Each group of teeth was subdivided into 0.5-mm intervals horizontally and vertically, and a force of 200 g was applied on each group. The center of resistance was defined as the point where the applied force induced parallel movement. Results The center of resistance of the 4 mandibular anterior teeth group was 13.0 mm apical and 6.0 mm posterior, that of the 6 mandibular anterior teeth group was 13.5 mm apical and 8.5 mm posterior, and that of the complete mandibular dentition group was 13.5 mm apical and 25.0 mm posterior to the incisal edge of the mandibular central incisors. Conclusions Finite-element analysis was useful in determining the 3D position of the center of resistance of the 4 mandibular anterior teeth group, 6 mandibular anterior teeth group, and complete mandibular dentition group. PMID:28127536

  7. Dentition, nutritional status and adequacy of dietary intake among older residents in assisted living facilities.

    Science.gov (United States)

    Saarela, Riitta K T; Lindroos, Eeva; Soini, Helena; Hiltunen, Kaija; Muurinen, Seija; Suominen, Merja H; Pitkälä, Kaisu H

    2016-06-01

    We examined the relationships between dentition, nutritional status and dietary intakes of energy, protein and micronutrients among older people in assisted living facilities in Helsinki. Poor dentition is associated with malnutrition. Less is known about how dentition is associated with detailed nutrient intakes in institutionalised older people. This cross-sectional study assessed 343 participants (mean age 83 years). Dentition was assessed by trained ward nurses and divided into edentulous participants without dentures (group 1), edentulous participants with removable dentures (group 2) and those with any natural teeth (group 3). Nutritional status was assessed by Mini Nutritional Assessment (MNA). The energy, protein and nutrient intakes were calculated from detailed 1-day food diaries and compared with the recommendations of the Finnish National Nutrition Council as a measure of dietary adequacy. Assessment included also participants' cognitive and functional status. Of the participants, 8.2, 39.1 and 52.8% were in groups 1, 2 and 3, respectively. Altogether 22% were malnourished according to MNA. Group 1 had the poorest nutritional status. A large proportion of participants consumed less than the recommended amounts of energy, protein or micronutrients. Half of the participants consumed nutritional care in long-term care. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

  8. Dental caries and fluorosis experience of 8-12-year-old children by early-life exposure to fluoride.

    Science.gov (United States)

    Do, Loc G; Miller, Jenifer; Phelan, Claire; Sivaneswaran, Shanti; Spencer, A John; Wright, Clive

    2014-12-01

    It is important to evaluate concurrently the benefit for dental caries and the risk for dental fluorosis from early exposure to fluoride among children. To evaluate associations of different levels of exposure to fluoride in early childhood with dental caries and dental fluorosis experience in school children. A Child Dental Health Survey (CDHS) was conducted among school children in the Australian state of New South Wales (NSW) in 2007. Trained and calibrated examination teams conducted oral epidemiologic examinations to assess caries experience as decayed, missing or filled tooth surfaces of the primary and permanent dentitions (dmfs/DMFS) and fluorosis using the Thylstrup & Fejerskov (TF) index on the maxillary central incisors only. A parental questionnaire collected information on residential histories and tap water usage to enable calculation of percentage of 3-year lifetime exposure to fluoride in water. Use of dietary fluoride supplements was also collected. Dental caries and fluorosis experience were compared among groups by levels of exposure to fluoride from water and fluoride supplements in bivariate and multivariable analysis, controlling for socioeconomic factors. Exposure to different fluoride sources varied in the group of 2611 children aged 8-12 years. Lower household income was significantly associated in both bivariate and multivariable analyses with the greater prevalence and severity of primary tooth caries among 8-10-year-old children and permanent tooth caries among 8-12 year old. Exposure to fluoride in water during the first 3 years of life was associated with both caries and fluorosis experience observed at age 8-12 years. Having higher percentage of 3-year lifetime exposure to fluoride in water was associated with higher prevalence of mostly mild fluorosis, but significantly lower prevalence and severity of caries in the primary and permanent dentitions. There were significant associations of dental caries and fluorosis experience with

  9. Management of a permanent tooth after trauma to deciduous predecessor: an evaluation by cone-beam computed tomography.

    Science.gov (United States)

    Gurgel, Carla Vecchione; Lourenço Neto, Natalino; Kobayashi, Tatiana Yuriko; Garib, Daniela Gamba; da Silva, Salete Moura Bonifácio; Machado, Maria Aparecida de Andrade Moreira; Oliveira, Thais Marchini

    2011-10-01

    Impaction of permanent teeth represents a clinical challenge with regard to diagnosis, treatment plan, and prognosis. There is a close relationship between deciduous teeth and permanent teeth germ, and any injury in the deciduous dentition may influence the permanent teeth eruption. The extent of the damage caused to the permanent teeth germ depends on the patient age at the time of injury, type of trauma, severity, and direction of the impact. Conventional radiographic images are frequently used for diagnosis; however, recent developments in three-dimensional (3D) imaging systems have enabled dentistry to visualize structural changes effectively, with better contrast and more details, close to the reality. The cone-beam computed tomography (CBCT) has been used in the diagnosis and treatment plan of these impacted teeth. The purpose of the present case report is to describe a successful conservative management of a retained permanent maxillary lateral incisor with delayed root development after a trauma through the deciduous predecessor in a 9 year-old patient. After clinical and radiographic examination, a CBCT examination of the maxilla was requested to complement the diagnosis, providing an accurate 3D position of the retained tooth and its relationship to adjacent structures. The proposed treatment plan was the surgical exposure and orthodontic traction of the retained tooth. The lateral incisor spontaneously erupted after 6 months. Therefore, this case report suggests that permanent teeth with incomplete root formation have a great potential for spontaneous eruption because no tooth malposition or mechanical obstacles are observed.

  10. Fluorosis en dentición temporal en un área con hidrofluorosis endémica Dental fluorosis in primary dentition in an endemic hydrofluorosis area

    Directory of Open Access Journals (Sweden)

    Juan Pablo Loyola-Rodríguez

    2000-06-01

    estimate the prevalence of dental fluorosis in primary dentition of a San Luis Potosi children population, and its association to fluoride concentration in drinking water and urine. An additional objective was, to develop, validate, and test a specific index for dental fluorosis in primary dentition. MATERIAL AND METHODS: From May 1997, to January 1999, we conducted a cross-sectional study to assess the prevalence of dental fluorosis in primary dentition. Study subjects were 100 children aged 3-6 years, selected at random from three kindergartens in three risk areas of San Luis Potosi. The specific index of dental fluorosis for primary dentition (Dental Fluorosis for Primary Dentition Index-DFPDI was validated by estimating fluoride concentrations in enamel of teeth with and without dental fluorosis. The Kruskal-Wallis test was used to assess the association between fluoride concentrations in drinking water and urine, with dental fluorosis; the association between risk area and dental fluorosis was assessed with the Mantel-Haenszel chi² test. RESULTS: . The prevalence of dental fluorosis in primary dentition was 78%; primary molars were most affected in both maxillae and the predominant color was a non-glossy white appearance. We found a strong direct correlation (r=0.93 between fluoride concentrations in primary teeth and the DFPDI. Associations were found between fluoride concentrations of drinking water and urine, with dental fluorosis (Kruskal-Wallis p=0.00001, and between risk area and dental fluorosis (Mantel-Haenszel chi² p=0.00001. CONCLUSIONS: DFPDI allowed adequate identification and grading of dental fluorosis in primary dentition. It is important to detect the initial toxic effects of fluoride exposure to predict dental fluorosis in permanent dentition and skeletal fluorosis.

  11. Regional odontodysplasia in early childhood: A clinical and histological study

    OpenAIRE

    Juliana O; Hermes Pretel; Ramalho Lizeti T; Santos-Pinto Lourdes; Giro Elisa M

    2009-01-01

    Regional odontodysplasia (RO) is a rare disorder of dental development. The affected teeth are clinically hypoplastic and hypocalcified, presenting a ghost-like appearance radiographically. The aim of this work was to report a clinical case of a child with both primary and permanent dentition affected by RO. The conducted therapy was based on a conservative approach, which consisted of follow-up clinical evaluations of the anomalous teeth. However, the endodontic treatment of the primary inci...

  12. Applicability of regression equation using widths of mandibular permanent first molars and incisors as a predictor of widths of mandibular canines and premolars in contemporary Indian population

    Directory of Open Access Journals (Sweden)

    Shalin Shah

    2013-01-01

    Full Text Available Background: Predicting the size of unerupted teeth during the mixed dentition period is a critical factor in managing the developing occlusion. Different studies found that the combined width of only the four mandibular permanent incisors is not a good predictor of the sum of unerupted mandibular permanent canines and premolars (SPCP. In 2007, Melgaço et al. developed a new method for SPCP by measuring the sum of the mandibular first permanent molars and four mandibular permanent incisors (SMI. Aim: It was aimed to evaluate the accuracy of this new method in comparison with Moyers′ mixed dentition analysis table in contemporary Indian population. Settings and Design: Sixty boys and 60 girls from Gandhinagar district (age ranged from 12 to 14 years were included. Materials and Methods: The mesiodistal crown widths of all fully erupted teeth were measured with digital vernier callipers and the odontometric values obtained were then subjected to statistical and linear regression analysis. Results: Student′s unpaired t-test gave statistically significant difference between the original values of teeth and the values obtained by Melgaço′s prediction equation as well as Moyers′ mixed dentition analysis table (P < 0.001. High values of correlation (r = 0.77 and determination coefficients (r2 = 0.59 were found while considering Melgaço′s method. Also, no statistically significant difference was found between the tooth sizes of males and females. Conclusion: From this study, it can be evaluated that Melgaço′s method gives better prediction and a simplified equation Y = 0.925X can be suggested for the present population.

  13. Comparative performance of deciduous and permanent dental morphology in detecting biological relatives.

    Science.gov (United States)

    Paul, Kathleen S; Stojanowski, Christopher M

    2017-09-01

    Dental morphology plays a key role in reconstructing population history and evolutionary relationships at global, regional, and intracemetery scales. At the inter-individual level, it is assumed that close biological kin exhibit greater phenotypic similarity than non-relatives. Heritability estimates provide one measure of phenotypic resemblance but are not easily incorporated into analyses of archaeological samples. In this study we evaluate the assumption that relatives are more similar phenotypically than non-relatives. We compare results for permanent dental morphology to those obtained using deciduous dental morphology in a matched dataset (Paul & Stojanowski, ). Permanent trait expression was scored from dental casts representing 69 sibling pairs, curated as part of the longitudinal Burlington Growth Study. Simulating a biodistance approach, 22 morphological traits of permanent tooth crowns were used to generate 69 inter-relative and 2,076 non-relative Euclidean distances. Following distance ordination, family-specific dispersion values were calculated from multidimensional scaling coordinates. Output was compared to that of a previous study that focused on deciduous crown variation in the same set of individuals (Paul & Stojanowski, ). Mantel tests were used to evaluate the correlation of a proxy genetic distance matrix to both the permanent and deciduous dental distance matrices. On average, inter-relative distances generated from morphological traits of permanent tooth crowns were smaller than expected by chance based on resampling (p distance matrices are significantly correlated with a matrix of genetic relatedness coefficients; however, the magnitude of the correlations was low. Overall, morphological traits of permanent tooth crowns perform moderately well in distinguishing relatives from non-relatives, but deciduous crown variations may provide a more direct reflection of the underlying genetic structure of intra-site or intra-cemetery samples

  14. Synchrotron imaging of dentition provides insights into the biology of Hesperornis and Ichthyornis, the “last” toothed birds

    OpenAIRE

    Dumont, Maïtena; Tafforeau, Paul; Bertin, Thomas; Bhullar, Bhart-Anjan; Field, Daniel; Schulp, Anne; Strilisky, Brandon; Thivichon-Prince, Béatrice; Viriot, Laurent; Louchart, Antoine

    2016-01-01

    Background The dentitions of extinct organisms can provide pivotal information regarding their phylogenetic position, as well as paleobiology, diet, development, and growth. Extant birds are edentulous (toothless), but their closest relatives among stem birds, the Cretaceous Hesperornithiformes and Ichthyornithiformes, retained teeth. Despite their significant phylogenetic position immediately outside the avian crown group, the dentitions of these taxa have never been studied in detail. To ob...

  15. Dose to the Developing Dentition During Therapeutic Irradiation: Organ at Risk Determination and Clinical Implications

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Reid F., E-mail: Reid.Thompson@uphs.upenn.edu [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Schneider, Ralf A., E-mail: ralf.schneider@psi.ch [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Albertini, Francesca; Lomax, Antony J.; Ares, Carmen; Goitein, Gudrun [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Hug, Eugen B. [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); ProCure Therapy Centers, New York, New York (United States)

    2013-05-01

    Purpose: Irradiation of pediatric facial structures can cause severe impairment of permanent teeth later in life. We therefore focused on primary and permanent teeth as organs at risk, investigating the ability to identify individual teeth in children and infants and to correlate dose distributions with subsequent dental toxicity. Methods and Materials: We retrospectively reviewed 14 pediatric patients who received a maximum dose >20 Gy(relative biological effectiveness, RBE) to 1 or more primary or permanent teeth between 2003 and 2009. The patients (aged 1-16 years) received spot-scanning proton therapy with 46 to 66 Gy(RBE) in 23 to 33 daily fractions for a variety of tumors, including rhabdomyosarcoma (n=10), sarcoma (n=2), teratoma (n=1), and carcinoma (n=1). Individual teeth were contoured on axial slices from planning computed tomography (CT) scans. Dose-volume histogram data were retrospectively obtained from total calculated delivered treatments. Dental follow-up information was obtained from external care providers. Results: All primary teeth and permanent incisors, canines, premolars, and first and second molars were identifiable on CT scans in all patients as early as 1 year of age. Dose-volume histogram analysis showed wide dose variability, with a median 37 Gy(RBE) per tooth dose range across all individuals, and a median 50 Gy(RBE) intraindividual dose range across all teeth. Dental follow-up revealed absence of significant toxicity in 7 of 10 patients but severe localized toxicity in teeth receiving >20 Gy(RBE) among 3 patients who were all treated at <4 years of age. Conclusions: CT-based assessment of dose distribution to individual teeth is feasible, although delayed calcification may complicate tooth identification in the youngest patients. Patterns of dental dose exposure vary markedly within and among patients, corresponding to rapid dose falloff with protons. Severe localized dental toxicity was observed in a few patients receiving the

  16. Root canal morphology of Chalcolithic and early bronze age human populations of El Mirador Cave (Sierra de Atapuerca, Spain).

    Science.gov (United States)

    Ceperuelo, Dolors; Lozano, Marina; Duran-Sindreu, Fernando; Mercadé, Montse

    2014-12-01

    This study provides a morphological characterization of the inner anatomy of the root canals of permanent first and second molars in Chalcolithic and early Bronze Age human fossils using cone-beam computed tomography. The general evolutionary trend in present-day human dentition is related to morphological simplification. As little is known about when this trend appeared in Homo sapiens populations, the aim of this work is to test the presence of modern radicular morphology 4,400 years ago. Fifty-four permanent first and second maxillary and mandibular molars of 17 individuals were included in the study. All maxillary first and second molars showed three separate roots. Almost all the lower molars analyzed (100% of first molars and 75% of second molars) had two separate roots. More differences in the canal system configuration were documented in the maxillary mesiobuccal roots than in the palatal or distobuccal roots. The most variable tooth in root and canal configuration is the maxillary second molar. It should be pointed out that 12.5% of the teeth analyzed showed a C-shaped root configuration.

  17. C-orthodontic microimplant for distalization of mandibular dentition in Class III correction.

    Science.gov (United States)

    Chung, Kyurhim; Kim, Seong-Hun; Kook, Yoonah

    2005-01-01

    A 16-year-old male patient with a Class III malocclusion and 2 lower missing central incisors presented for treatment. The treatment plan consisted of asymmetrically distalizing the lower dentition and regaining space for lower anterior prosthetic work. C-implants were to be used as anchorage for Class III intermaxillary elastics, and two C-orthodontic microimplants (C-implants) were placed in the interdental spaces between the upper second premolars and first molars. The particular design of the C-implant head minimized gingival irritation during the orthodontic treatment. Sliding jigs were applied on the buccal for distalization of the lower posterior teeth. The correct overbite and overjet were obtained by distalizing the entire lower dentition into its proper position with C-implant anchorage, which contributed to an improvement in facial balance. It took 15 months to treat this case. The application of this new microimplant, considerations for case selection, and the sequence of treatment are presented.

  18. Esthetic rehabilitation of a worn dentition with a minimally invasive prosthetic procedure (MIPP).

    Science.gov (United States)

    Fradeani, Mauro; Barducci, Giancarlo; Bacherini, Leonardo

    2016-01-01

    A minimally invasive prosthetic procedure (MIPP) for the esthetic rehabilitation of the complete arch advocates the preservation of enamel to optimize the adhesive bond of the luting agent to both the tooth surface and the etchable ceramic restoration. When esthetic rehabilitation of a worn dentition is required, a MIPP can be selected to reduce the biological cost of removing additional enamel tooth structure. The fundamental steps to achieve this goal are to: (1) increase the vertical dimension of occlusion (VDO); (2) reduce the thickness of the monolithic ceramic material; (3) preserve the enamel during tooth preparation; and (4) adhesively bond the etchable ceramic restorations. This article presents a comprehensive, minimally invasive prosthetic treatment approach for the esthetic rehabilitation of a severely worn dentition using a lithium disilicate all-ceramic material with partial and complete coverage restorations.

  19. [A clinical observation of therapeutic alliance of orthodontics and implant prosthodontics for dentition defect with malocclusion].

    Science.gov (United States)

    Zhou, Gong-liang; Liu, Die; Liang, Xing; Wang, Jun; Tang, Li; Zhang, Ning

    2008-10-01

    To explore the clinical effect of the multidisciplinary treatment combined orthodontics with implant prosthodontics for cases of dentition defect with malocclusion. Seventeen cases of dentition defect with malocclusion were observed. All the cases accepted the orthodontic treatment in order to establish normal occlusion and achieve adequate space for implants. After that, the missing teeth were replaced by implant-supported denture. The clinical effect was evaluated by clinical examination and radiographic examination. Satisfactory esthetic and functional results were achieved for all the cases. The follow-up time ranged from 12 months to 48 months. 76 implants were inserted totally. Two of them were extracted due to peri-implantitis. However, the other 74 implants were stable with an average loading time of 32 months. The cumulative survival rate was 97.4%. The multidisciplinary approach combined orthodontics with implant prosthodontics was an effective treatment option for cases of dentiton defect with malocclusion.

  20. The dentition of the enigmatic pycnodont fish, Athrodon wittei (Fricke, 1876 (Neopterygii, Pycnodontiformes; Late Jurassic; NW Germany

    Directory of Open Access Journals (Sweden)

    J. Kriwet

    2008-08-01

    Full Text Available Most pycnodontiform fishes are represented by their distinctive dentition alone, whereas articulated skeletons are very rare and the systematic position of most taxa based upon isolated teeth and the association of upper and lower dentitions to a specific taxon is still somewhat ambiguous in most cases. The vomerine dentition of the Late Jurassic pycnodontiform Athrodon wittei (Fricke, 1876, which is described here for the first time, is characterised by a high number of lateral tooth rows and the distinct morphology of the teeth. The dentition of Athrodon differs from most other pycnodont dentitions in the peculiar arrangement of the teeth into irregular rows and not well-differentiated principal row. The absence of regular tooth rows is not considered plesiomorphic here but most probably was achieved independently in different pycnodont lineages. The high number of lateral tooth rows (> four is considered to be autapomorphic for Athrodon. The pycnodont fish Nonaphalagodus from the Albian of Texas, which also is known by isolated dentitions only, resembles Athrodon in the high number of vomerine tooth rows but differs in that this taxon displays the more derived feature of the teeth being arranged more regularly and individualized rows. doi:10.1002/mmng.200800002

  1. Aesthetic And Functional Rehabilitation Of The Primary Dentition Affected By Amelogenesis Imperfecta.

    OpenAIRE

    Maria Carolina Salomé Marquezin; Bruna Raquel Zancopé; Larissa Ferreira Pacheco; Maria Beatriz Duarte Gavião; Fernanda Miori Pascon

    2015-01-01

    The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI) in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars wit...

  2. The uniqueness of the human dentition as forensic evidence: a systematic review on the technological methodology.

    Science.gov (United States)

    Franco, Ademir; Willems, Guy; Souza, Paulo Henrique Couto; Bekkering, Geertruida E; Thevissen, Patrick

    2015-11-01

    The uniqueness of human dentition is routinely approached as identification evidence in forensic odontology. Specifically in bitemark and human identification cases, positive identifications are obtained under the hypothesis that two individuals do not have the same dental features. The present study compiles methodological information from articles on the uniqueness of human dentition to support investigations into the mentioned hypothesis. In April 2014, three electronic library databases (SciELO®, MEDLINE®/PubMed®, and LILACS®) were systematically searched. In parallel, reference lists of relevant studies were also screened. From the obtained articles (n = 1235), 13 full-text articles were considered eligible. They were examined according to the studied parameters: the sample size, the number of examined teeth, the registration technique for data collection, the methods for data analysis, and the study outcomes. Six combinations of studied data were detected: (1) dental shape, size, angulation, and position (n = 1); (2) dental shape, size, and angulation (n = 4); (3) dental shape and size (n = 5); (4) dental angulation and position (n = 2); (5) dental shape and angulation (n = 1); and (6) dental shape (n = 1). The sample size ranged between 10 and 1099 human dentitions. Ten articles examined the six anterior teeth, while three articles examined more teeth. Four articles exclusively addressed three-dimensional (3D) data registration, while six articles used two-dimensional (2D) imaging. In three articles, both imaging registrations were combined. Most articles (n = 9) explored the data using landmark placement. The other articles (n = 4) comprised digital comparison of superimposed dental contours. Although there were large methodological variations within the investigated articles, the uniqueness of human dentition remains unproved.

  3. Biostimulative laser therapy in difficult dentition of a lower wisdom tooth

    Science.gov (United States)

    Grzesiak-Janas, Grazyna

    1996-03-01

    In a group of 66 patients treated for difficult dentition of the lower wisdom tooth, 33 were subjected to biostimulative laser therapy. In this group 20 persons were treated conservatively together with laser therapy and 13 underwent surgical treatment together with exposure to laser irradiation. During the treatment a positive influence of the laser was found, i.e. a decrease in pain, edema, and trismus.

  4. Wear biomechanics in the slicing dentition of the giant horned dinosaur Triceratops

    OpenAIRE

    Erickson, Gregory M.; Sidebottom, Mark A.; Kay, David I.; Turner, Kevin T.; Ip, Nathan; Norell, Mark A.; Sawyer, W. Gregory; Krick, Brandon A.

    2015-01-01

    Herbivorous reptiles rarely evolve occluding dentitions that allow for the mastication (chewing) of plant matter. Conversely, most herbivorous mammals have occluding teeth with complex tissue architectures that self-wear to complex morphologies for orally processing plants. Dinosaurs stand out among reptiles in that several lineages acquired the capacity to masticate. In particular, the horned ceratopsian dinosaurs, among the most successful Late Cretaceous dinosaurian lineages, evolved slici...

  5. Full mouth rehabilitation of the patient with severely worn dentition: a case report

    OpenAIRE

    Song, Mi-Young; Park, Ji-Man; Park, Eun-Jin

    2010-01-01

    The severe wear of anterior teeth facilitates the loss of anterior guidance, which protects the posterior teeth from wear during excursive movement. The collapse of posterior teeth also results in the loss of normal occlusal plane and the reduction of the vertical dimension. This case report describes 77-year-old female, who had the loss of anterior guidance, the severe wear of dentition, and the reduction of the vertical dimension. Occlusal overlay splint was used after the decision of incre...

  6. The hidden teeth of sloths: evolutionary vestiges and the development of a simplified dentition

    OpenAIRE

    Lionel Hautier; Helder Gomes Rodrigues; Guillaume Billet; Asher, Robert J

    2016-01-01

    International audience; Xenarthrans are unique among mammals in retaining simplified teeth that are rootless and homodont, which makes it difficult to determine dental homologies. We apply computerized tomography to prenatal developmental series of extant sloths, Bradypus and Choloepus, to further elucidate the patterns of morphological variation in their dentition. We also propose new criteria based on sequences of dental mineralization, and the presence of vestigial teeth, to distinguish be...

  7. Effect of serial extraction alone on crowding: spontaneous changes in dentition after serial extraction.

    Science.gov (United States)

    Yoshihara, T; Matsumoto, Y; Suzuki, J; Sato, N; Oguchi, H

    2000-12-01

    We examined changes in dentition after serial extraction in subjects who wore no appliances to determine the relationships between changes in dentition and improvement in dental crowding. Mandibular dental casts and lateral cephalograms from 31 subjects who had undergone serial extraction without orthodontic treatment were analyzed at 3 stages: before extraction of the deciduous canines (T1), after extraction of first premolars (T2), and at the end of the observation period (T3). Although movements of the first molar cusp and apex from T2 to T3 were significantly greater than from T1 to T2, movements of the incisor cusp and apex from T1 to T2 were significantly greater than from T2 to T3. The first molar tipped mesially from T1 to T2 but tipped distally from T2 to T3. The distal tipping of the incisor from T1 to T2 was significantly greater than from T2 to T3. These results suggest that the main changes in dentition from T1 to T2 are different from those from T2 to T3. The correlations between the annual change in the canine movement or tipping from T2 to T3 and the annual change in the irregularity index at the same time were significant. These results suggest that the canine movement or tipping contributed to the correction of the anterior crowding from T2 to T3.

  8. Wear biomechanics in the slicing dentition of the giant horned dinosaur Triceratops.

    Science.gov (United States)

    Erickson, Gregory M; Sidebottom, Mark A; Kay, David I; Turner, Kevin T; Ip, Nathan; Norell, Mark A; Sawyer, W Gregory; Krick, Brandon A

    2015-06-01

    Herbivorous reptiles rarely evolve occluding dentitions that allow for the mastication (chewing) of plant matter. Conversely, most herbivorous mammals have occluding teeth with complex tissue architectures that self-wear to complex morphologies for orally processing plants. Dinosaurs stand out among reptiles in that several lineages acquired the capacity to masticate. In particular, the horned ceratopsian dinosaurs, among the most successful Late Cretaceous dinosaurian lineages, evolved slicing dentitions for the exploitation of tough, bulky plant matter. We show how Triceratops, a 9-m-long ceratopsian, and its relatives evolved teeth that wore during feeding to create fullers (recessed central regions on cutting blades) on the chewing surfaces. This unique morphology served to reduce friction during feeding. It was achieved through the evolution of a complex suite of osseous dental tissues rivaling the complexity of mammalian dentitions. Tribological (wear) properties of the tissues are preserved in ~66-million-year-old teeth, allowing the creation of a sophisticated three-dimensional biomechanical wear model that reveals how the complexes synergistically wore to create these implements. These findings, along with similar discoveries in hadrosaurids (duck-billed dinosaurs), suggest that tissue-mediated changes in dental morphology may have played a major role in the remarkable ecological diversification of these clades and perhaps other dinosaurian clades capable of mastication.

  9. The "index technique" in worn dentition: a new and conservative approach.

    Science.gov (United States)

    Ammannato, Riccardo; Ferraris, Federico; Marchesi, Giulio

    2015-01-01

    The development and reliability of adhesive resin composite systems have offered clinicians a further option for the management of tooth-surface loss. Patients with minimum, moderate, and severe hard tissue wear can be treated based on the application of minimally invasive adhesive composite restorations for posterior and anterior worn dentition. This article presents the "index technique", a new and very conservative approach to the management of worn dentition. The technique allows for a purely additive treatment without sacrificing healthy hard tooth tissue. It follows the principles of bioeconomics (maximum conservation of healthy tissue) and the reinforcing of residual dental structure. Depending on the severity of enamel and dentin wear, the number of caries, and the size of existing restorations, different treatment options can be applied to each tooth: direct and indirect partial restorations or full crowns. It is essential to diagnose and treat tooth-surface loss in order to properly restore biomechanics, function, and esthetics by means of adhesive restorations. This article proposes that the index technique is a fast and conservative approach for the planning and management of a fullmouth adhesive treatment in all cases of worn dentition. The technique is based on stamping composite directly on the tooth surface by means of a transparent index created from the full-mouth wax-up following an initially planned increase in occlusal vertical dimension (OVD).

  10. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens.

    Science.gov (United States)

    Sidiq, Mohsin; Yousuf, Asif; Bhat, Manohar; Sharma, Rajesh; Bhargava, Neha; Ganta, Shravani

    2015-01-01

    The aim of this case study was to report a potentially convenient approach instead of a conventional orthodontic procedure for correcting severe rotation of anterior tooth of an 11-year-old Indian boy, with a mixed dentition class I malocclusion. The child reported seeking treatment for severely rotated upper right central incisor with mesiodens and a single tooth crossbite. The supernumerary tooth was first extracted and bondable buttons were placed on the rotated tooth, an appliance composed of a removable plate with Adam's clasp with distal extension and a loop for engagement of elastics was delivered. Circumferential supracrestal fibrotomy was performed on the corrected derotated tooth. Then, Hawley's appliance with a z-spring and posterior bite plane was fabricated and placed for correction of crossbite. Thus, this removable appliance can be a simplified and a cost-effective treatment alternative for derotation of anterior tooth, especially during the mixed dentition period. How to cite this article: Sidiq M, Yousuf A, Bhat M, Sharma R, Bhargava N, Ganta S. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens. Int J Clin Pediatr Dent 2015;8(3):234-238.

  11. Applicability of Moyers analysis in mixed dentition: A systematic review.

    Science.gov (United States)

    Galvão, Mariana de Aguiar Bulhões; Dominguez, Gladys Cristina; Tormin, Sérgio Thomaz; Akamine, Alex; Tortamano, André; de Fantini, Solange Mongelli

    2013-01-01

    Moyers analysis is widely used for analyzing mixed dentition, however, the accuracy of its theoretical probability tables has been recently questioned. Taking into consideration the fact the mixed dentition analysis is of paramount importance to precisely determine the space needed for alignment of canines and premolars, this research aimed at objectively assessing in the literature such an important step for orthodontic diagnosis. A computerized search involving articles published on PubMed and Lilacs between 1990 and September, 2011 was conducted in accordance with the method described in the Cochrane 5.1.0 handbook. The research resulted in a sample composed of 629 articles. The inclusion criteria were: Articles using the Moyers analysis with a sample greater or equal to 40 patients. Conversely, the exclusion criteria were: Dental casts of patients with syndromes or oral cleft, researches conducted with a literature review, only, or clinical case reports and researches conducted before 1990. For this systematic review, 19 articles were selected. Based on the literature available, we can conclude that Moyers mixed dentition analysis must be carefully used, since the majority of the articles analyzed showed that the probability of 75% was not as accurate as expected, leading to the need of adapting the probability levels depending on the study population.

  12. Qualitative permanence of Lotka-Volterra equations.

    Science.gov (United States)

    Hofbauer, Josef; Kon, Ryusuke; Saito, Yasuhisa

    2008-12-01

    In this paper, we consider permanence of Lotka-Volterra equations. We investigate the sign structure of the interaction matrix that guarantees the permanence of a Lotka-Volterra equation whenever it has a positive equilibrium point. An interaction matrix with this property is said to be qualitatively permanent. Our results provide both necessary and sufficient conditions for qualitative permanence.

  13. Root maturation and dentin-pulp response to enamel matrix derivative in pulpotomized permanent teeth.

    Science.gov (United States)

    Darwish, Sherif S; Abd El Meguid, Shadia H; Wahba, Nadia A; Mohamed, Ahmed A-R; Chrzanowski, Wojciech; Abou Neel, Ensanya A

    2014-01-01

    The success of pulpotomy of young permanent teeth depends on the proper selection of dressing materials. This study aimed to evaluate the histological and histomorphometric response of dentin-pulp complex to the enamel matrix derivative (Emdogain(®) gel) compared to that of calcium hydroxide when used as a pulp dressing in immature young permanent dogs' teeth. Dentin-like tissues bridging the full width of the coronal pulp at the interface between the injured and healthy pulp tissues were seen after 1 month in both groups. With time, the dentin bridge increased in thickness for calcium hydroxide but disintegrated and fully disappeared for Emdogain-treated group. Progressive inflammation and total pulp degeneration were only evident with Emdogain-treated group. The root apices of Emdogain-treated teeth became matured and closed by cementum that attached to new alveolar bone by a well-oriented periodontal ligament. In young permanent dentition, Emdogain could be a good candidate for periodontium but not dentino-pulpal complex regeneration.

  14. Root maturation and dentin–pulp response to enamel matrix derivative in pulpotomized permanent teeth

    Directory of Open Access Journals (Sweden)

    Sherif S Darwish

    2014-01-01

    Full Text Available The success of pulpotomy of young permanent teeth depends on the proper selection of dressing materials. This study aimed to evaluate the histological and histomorphometric response of dentin–pulp complex to the enamel matrix derivative (Emdogain® gel compared to that of calcium hydroxide when used as a pulp dressing in immature young permanent dogs’ teeth. Dentin-like tissues bridging the full width of the coronal pulp at the interface between the injured and healthy pulp tissues were seen after 1 month in both groups. With time, the dentin bridge increased in thickness for calcium hydroxide but disintegrated and fully disappeared for Emdogain-treated group. Progressive inflammation and total pulp degeneration were only evident with Emdogain-treated group. The root apices of Emdogain-treated teeth became matured and closed by cementum that attached to new alveolar bone by a well-oriented periodontal ligament. In young permanent dentition, Emdogain could be a good candidate for periodontium but not dentino–pulpal complex regeneration.

  15. Transient or permanent fisheye views

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2012-01-01

    , about the benefits and limitations of transient visualizations. We describe an experiment that compares the usability of a fisheye view that participants could call up temporarily, a permanent fisheye view, and a linear view: all interfaces gave access to source code in the editor of a widespread......Transient use of information visualization may support specific tasks without permanently changing the user interface. Transient visualizations provide immediate and transient use of information visualization close to and in the context of the user’s focus of attention. Little is known, however...... programming environment. Fourteen participants performed varied tasks involving navigation and understanding of source code. Participants used the three interfaces for between four and six hours in all. Time and accuracy measures were inconclusive, but subjective data showed a preference for the permanent...

  16. Lodestone: Nature's own permanent magnet

    Science.gov (United States)

    Wasilewski, P.

    1976-01-01

    Magnetic hysteresis and microstructural details are presented which explain why the class of magnetic iron ores defined as proto-lodestones, can behave as permanent magnets, i.e. lodestones. Certain of these proto-lodestones which are not permanent magnets can be made into permanent magnets by charging in a field greater than 1000 oersted. This fact, other experimental observations, and field evidence from antiquity and the middle ages, which seems to indicate that lodestones are found as localized patches within massive ore bodies, suggests that lightning might be responsible for the charging of lodestones. The large remanent magnetization, high values of coercive force, and good time stability for the remanent magnetization are all characteristics of proto-lodestone iron ores which behave magnetically as fine scale ( 10 micrometer) intergrowths when subjected to magnetic hysteresis analysis. The magnetic results are easily understood by analysis of the complex proto lodestone microstructural patterns observable at the micrometer scale and less.

  17. Topology optimized permanent magnet systems

    CERN Document Server

    Bjørk, R; Insinga, A R

    2016-01-01

    Topology optimization of permanent magnet systems consisting of permanent magnets, high permeability iron and air is presented. An implementation of topology optimization for magnetostatics is discussed and three examples are considered. First, the Halbach cylinder is topology optimized with iron and an increase of 15% in magnetic efficiency is shown, albeit with an increase of 3.8 pp. in field inhomogeneity - a value compared to the inhomogeneity in a 16 segmented Halbach cylinder. Following this a topology optimized structure to concentrate a homogeneous field is shown to increase the magnitude of the field by 111% for the chosen dimensions. Finally, a permanent magnet with alternating high and low field regions is considered. Here a $\\Lambda_\\mathrm{cool}$ figure of merit of 0.472 is reached, which is an increase of 100% compared to a previous optimized design.

  18. Connecting Temporary and Permanent Organizing

    DEFF Research Database (Denmark)

    Stjerne, Iben Sandal; Velikova, Silviya Svejenova

    2016-01-01

    This paper investigates the relationship between a permanent organization and a series of temporary organizations. It draws on an in-depth study of the process through which a Danish film production company, seeking to balance innovation and persistence in a troubled industry, struggles to realize...... a novel children’s film and its sequels. The study reveals tensions at different levels as well as boundary work and boundary roles that address them, bringing in shadows of past and future projects. The study extends the understanding of the dialectic between temporary and permanent organizing...... by emphasizing how ongoing work at different boundaries affects the permanent and temporary organizing’s connectedness and outcomes. It also challenges the overly bracketed view of temporary organizations, suggesting a temporality perspective on temporariness....

  19. 儿童时期牙颌畸形的早期防治%Early prevention and treatment of childhood malocclu-sion

    Institute of Scientific and Technical Information of China (English)

    汪隼

    2013-01-01

    It’s a long process for children from birth to the establishment of permanent teeth dentition. During this pe-riod,caries,teeth dysplasia and oral bad habits etc.,will af-fect the growth of the teeth,occlusion and facial,resulting in the malocclusion. Taking early treatment for the children in the peak of growth will simplify complex issues and get the best treatment results,block the development of malocclusion with a relatively simple treatment in a relatively short period, and guide the normal growth of the teeth,occlusion and fa-cial. According to children's growth characteristics and based on the law of growth and development,early diagnosis and treatment should be carried out. Early treatment may be part of the whole treatment plans,and most of the children often need conventional orthodontic treatment after period of re-placed teeth. Early treatment in mixed dentition period is a part of orthodontic treatment from mixed dentition period to permanent teeth dentition.%小儿从出生到建立完好的恒牙列,是个漫长的过程。在此期间,常见的龋、牙齿发育异常、口腔不良习惯等,均会对牙、颌、面的生长产生影响,导致面型异常及各种错牙合畸形。如对正处于生长发育高峰期的儿童采取早期治疗,治疗效果最好,可使复杂问题简单化,常可在较短的时间内,用比较简单的矫治方法和矫治器改正,及早地阻断错牙合畸形的发展,引导牙、颌、面正常发育。开展早期治疗,要根据儿童的生长发育特点,依据生长发育的规律和发育的顺序进行诊断和治疗。早期治疗可能只是整个治疗计划的一部分,大多数的患儿常常需要到替牙期后再进行后期常规正畸治疗,所以要把乳牙、混合牙列期的早期治疗作为从乳牙、混合牙列期到恒牙列期的整体正畸治疗过程的一个环节来正确认识。

  20. Unerupted Primary Molar Teeth Positioned Inferior to the Permanent Premolar: A Case Report

    Directory of Open Access Journals (Sweden)

    A. Bagheri

    2012-01-01

    Full Text Available Primary tooth impaction is a rare finding during the development of primary dentition. Several factors contribute to the impaction of a deciduous tooth. This report describes the diagnosis and treatment of a 10-year-old boy who presented an impacted second primary mandibular molar. This tooth, located inferior to the second premolar together with an odontoma, was positioned superior to the premolar teeth. Treatment consisted of surgical removal of the impacted deciduoustooth and odontoma and placement of a passive lower lingual holdingarch. Periodic examination was indicated for follow- up. Early intervention was recommended to manage orofacial disfigurement and to avoid consequent problems.

  1. Electromagnetic acceleration of permanent magnets

    CERN Document Server

    Dolya, S N

    2015-01-01

    We consider the acceleration of the permanent magnets, consisting of neodymium iron boron by means of the running magnetic field gradient. It is shown that the specific magnetic moment per nucleon in neodymium iron boron is determined by the remained magnetization of the substance. The maximum accessable gradient of the magnetic field accelerating the permanent magnets is determined by the coercive force thirty kilogauss. For the neodymium iron boron magnets this gradient is equal to twenty kilogauss divided by one centimeter. The finite velocity of the magnets six kilometers per second, the length of acceleration is six hundred thirty-seven meters.

  2. Prevalence of dental anomalies and enamel hypoplasia in primary dentition among preschool children of West Godavari District, Andhra Pradesh -A cross - sectional study

    Directory of Open Access Journals (Sweden)

    Suzan Sahana

    2013-01-01

    Full Text Available Background: It is axiomatic that Pediatric dental anomalies and enamel hypoplasia (E.H are routinely encountered in primary dentition and early detection and prudent management of the condition facilitates normal occlusal development. Objectives: To determine the prevalence of various dental anomalies and enamel hypoplasia in preschool children between two to six years of age. Materials & Method: A total of 1898 children, between two to six years were randomly selected and screened for dental anomalies and enamel hypoplasia The chi square test was used to analyze the data statistically. Results: The overall prevalence rate of dental anomalies and enamel hypoplasia in this study was 0.63% and 8.95% respectively. Double teeth were the most frequently reported dental anomaly while supernumerary teeth were least reported. None of them reported with hypodontia.

  3. An evaluation of the accuracy of semi-permanent skin marks for breast cancer irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Probst, H. [Faculty of Health and Wellbeing, Sheffield Hallam University, Collegiate Crescent Campus, Sheffield S10 2BP (United Kingdom)]. E-mail: h.probst@shu.ac.uk; Dodwell, D. [Cookridge Hospital Leeds (United Kingdom); Gray, J.C. [University of Newcastle (United Kingdom); Holmes, M. [Leeds Metropolitan University (United Kingdom)

    2006-08-15

    A randomised trial was designed to investigate the accuracy of semi-permanent ink marks versus permanent tattoos for early stage breast cancer irradiation. No significant difference in random and systematic errors was identified between the two groups. On multivariate analysis no specific patient characteristic had a major influence on the systematic errors identified.

  4. Application of dynamic elect roneuro-stimulation at treatment of patients with deformations of dentitions complicated by muscular and articular dysfunction

    OpenAIRE

    2013-01-01

    The purpose: to evaluate the efficacy of dynamic electroneurostimulation in the complex treatment of patients with strains of dentition complicated by muscular and articular dysfunction. Material and methods. A total of 38 patients aged 25 to 49 years with the strains of dentition, complicated by muscular and articular dysfunction. Clinical, radiological and graphical methods have been applied. In the combined treatment of dentition deformities complicated by muscular and articular dysfunctio...

  5. Origin and evolution of gnathostome dentitions: a question of teeth and pharyngeal denticles in placoderms.

    Science.gov (United States)

    Zerina, Johanson; Smith, Moya M

    2005-05-01

    The fossil group Placodermi is the most phylogenetically basal of the clade of jawed vertebrates but lacks a marginal dentition comparable to that of the dentate Chondrichthyes, Acanthodii and Osteichthyes (crown-group Gnathostomata). The teeth of crown-group gnathostomes are part of an ordered dentition replaced from, and patterned by, a dental lamina, exemplified by the elasmobranch model. A dentition recognised by these criteria has been previously judged absent in placoderms, based on structural evidence such as absence of tooth whorls and typical vertebrate dentine. However, evidence for regulated tooth addition in a precise spatiotemporal order can be observed in placoderms, but significantly, only within the group Arthrodira. In these fossils, as in other jawed vertebrates with statodont, non-replacing dentitions, new teeth are added at the ends of rows below the bite, but in line with biting edges of the dentition. The pattern is different on each gnathal bone and probably arises from single odontogenic primordia on each, but tooth rows are arranged in a distinctive placoderm pattern. New teeth are made of regular dentine comparable to that of crown-gnathostomes, formed from a pulp cavity. This differs from semidentine previously described for placoderm gnathalia, a type present in the external dermal tubercles. The Arthrodira is a derived taxon within the Placodermi, hence origin of teeth in placoderms occurs late in the phylogeny and teeth are convergently derived, relative to those of other jawed vertebrates. More basal placoderm taxa adopted other strategies for providing biting surfaces and these vary substantially, but include addition of denticles to the growing gnathal plates, at the margins of pre-existing denticle patches. These alternative strategies and apparent absence of regular dentine have led to previous interpretations that teeth were entirely absent from the placoderm dentition. A consensus view emerged that a dentition, as developed

  6. Development and evolution of the unique cetacean dentition

    Directory of Open Access Journals (Sweden)

    Brooke A. Armfield

    2013-02-01

    Full Text Available The evolutionary success of mammals is rooted in their high metabolic rate. A high metabolic rate is sustainable thanks to efficient food processing and that in turn is facilitated by precise occlusion of the teeth and the acquisition of rhythmic mastication. These major evolutionary innovations characterize most members of the Class Mammalia. Cetaceans are one of the few groups of mammals in which precise occlusion has been secondarily lost. Most toothed whales have an increased number of simple crowned teeth that are similar along the tooth row. Evolution toward these specializations began immediately after the time cetaceans transitioned from terrestrial-to-marine environments. The fossil record documents the critical aspects of occlusal evolution of cetaceans, and allows us to pinpoint the evolutionary timing of the macroevolutionary events leading to their unusual dental morphology among mammals. The developmental controls of tooth differentiation and tooth number have been studied in a few mammalian clades, but nothing is known about how these controls differ between cetaceans and mammals that retain functional occlusion. Here we show that pigs, a cetacean relative with regionalized tooth morphology and complex tooth crowns, retain the typical mammalian gene expression patterns that control early tooth differentiation, expressing Bmp4 in the rostral (mesial, anterior domain of the jaw, and Fgf8 caudally (distal, posterior. By contrast, dolphins have lost these regional differences in dental morphology and the Bmp4 domain is extended into the caudal region of the developing jaw. We hypothesize that the functional constraints underlying mammalian occlusion have been released in cetaceans, facilitating changes in the genetic control of early dental development. Such major developmental changes drive morphological evolution and are correlated with major shifts in diet and food processing during cetacean evolution.

  7. Development and evolution of the unique cetacean dentition.

    Science.gov (United States)

    Armfield, Brooke A; Zheng, Zhengui; Bajpai, Sunil; Vinyard, Christopher J; Thewissen, Jgm

    2013-01-01

    The evolutionary success of mammals is rooted in their high metabolic rate. A high metabolic rate is sustainable thanks to efficient food processing and that in turn is facilitated by precise occlusion of the teeth and the acquisition of rhythmic mastication. These major evolutionary innovations characterize most members of the Class Mammalia. Cetaceans are one of the few groups of mammals in which precise occlusion has been secondarily lost. Most toothed whales have an increased number of simple crowned teeth that are similar along the tooth row. Evolution toward these specializations began immediately after the time cetaceans transitioned from terrestrial-to-marine environments. The fossil record documents the critical aspects of occlusal evolution of cetaceans, and allows us to pinpoint the evolutionary timing of the macroevolutionary events leading to their unusual dental morphology among mammals. The developmental controls of tooth differentiation and tooth number have been studied in a few mammalian clades, but nothing is known about how these controls differ between cetaceans and mammals that retain functional occlusion. Here we show that pigs, a cetacean relative with regionalized tooth morphology and complex tooth crowns, retain the typical mammalian gene expression patterns that control early tooth differentiation, expressing Bmp4 in the rostral (mesial, anterior) domain of the jaw, and Fgf8 caudally (distal, posterior). By contrast, dolphins have lost these regional differences in dental morphology and the Bmp4 domain is extended into the caudal region of the developing jaw. We hypothesize that the functional constraints underlying mammalian occlusion have been released in cetaceans, facilitating changes in the genetic control of early dental development. Such major developmental changes drive morphological evolution and are correlated with major shifts in diet and food processing during cetacean evolution.

  8. Comparison of maxillary and mandibular dental arch forms by studying Fourier series developed from mathematically estimated dentitions.

    Science.gov (United States)

    Mikami, Hiroko; Nakatsuka, Michiko; Iwai, Yasutomo

    2010-11-01

    We conducted a Fourier analysis on data obtained using correlation and principal component analyses of parallel-standardized dental study models; both maxillary and mandibular dental arches were predominantly round square in shape. The present study compared and determined the contribution ratio and reproducible coefficients of amplitudes (factors affecting dental arch forms), and demonstrated that the 1st to 4th and the 1st to 6th Fourier harmonics reproduced maxillary and mandibular dental arch forms, respectively. The correlation analyses of the constant term and amplitudes demonstrated that significant differences in the 2nd harmonic amplitude was strongly correlated with the curvature of anterior teeth and the length-to-width ratio in maxillary dentitions. By comparison of the constant term and amplitudes between different arch types, we did not observe significant differences in the constant term and the 1st amplitude of maxillary dentitions and in constant term and all amplitudes of mandibular dentitions. Nevertheless, the study revealed high contribution ratios of the 1st (in mandibular dentitions) and the 2nd (in maxillary dentitions) amplitudes essentially affecting the reproducibility of arch forms. The 1st amplitudes demonstrated a bow-like arrangement of all arch types, while the 2nd amplitudes adjusted the anterior-teeth curvature and in particular demonstrated the length-to-width ratio of maxillary dentitions. The 3rd and the 4th amplitudes were also determinants of the anterior-teeth curvature of maxillary dentitions. The 6th amplitude was necessary for reproduction, but showed no difference between varying mandibular dental arch types. Collectively, we conclude that the establishment of a Fourier series significantly reproduced maxillary but not mandibular dental arch forms.

  9. Magnetic Fields: Visible and Permanent.

    Science.gov (United States)

    Winkeljohn, Dorothy R.; Earl, Robert D.

    1983-01-01

    Children will be able to see the concept of a magnetic field translated into a visible reality using the simple method outlined. Standard shelf paper, magnets, iron filings, and paint in a spray can are used to prepare a permanent and well-detailed picture of the magnetic field. (Author/JN)

  10. Overview on permanent magnetic actuator

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Permanent magnetic actuator (PMA), as a new electronic actuator of vacuum circuit breakers, certainly will be used to replace the traditional mechanical actuator. It has such advantages as simple structure, high reliability, free maintenance, and so on. This paper summarizes the development, structure, magnetic analysis, character analysis, and control strategy of PMA, and also predicts the future trend of PMA development

  11. Dental health and diet in early medieval Ireland.

    Science.gov (United States)

    Novak, Mario

    2015-09-01

    With the aim to get a better picture of dental health, diet and nutrition in early medieval Ireland a population-based study focusing on several attributes of oral health in adult individuals was conducted. The study focused on possible differences between sexes and age groups in terms of frequency and distribution of studied pathologies in order to determine whether these differences result from different diets, cultural practices or are age-related. Permanent dentitions belonging to adult individuals from five Irish early medieval sites were examined for the evidence of caries, ante-mortem tooth loss, abscesses, calculus, alveolar bone resorption and tooth wear. All pathologies were analysed and presented by teeth and alveoli. A total of 3233 teeth and 3649 alveoli belonging to 167 individuals (85 males and 82 females) were included into the analysis. Males exhibited significantly higher prevalence of abscesses, heavy wear and alveolar bone resorption, while females exhibited significantly higher prevalence of calculus. All studied dento-alveolar pathologies showed a strong correlation with advanced age, except calculus in females. Additionally, dental wear associated with habitual activities was observed in two females. The results of the present study confirm the data gained by written sources and stable isotopes analyses suggesting the diet of the early Irish was rich in carbohydrates with only occasional use of meat. Furthermore, significant differences between the sexes in terms of recorded pathologies strongly suggest different nutritional patterns with females consuming foods mostly based on carbohydrates in comparison to males. The observed sex-differences might also occur due to differences between male and female sex such as reproductive biology and pregnancy, a somewhat different age distributions, but also as a result of different cultural practices between the sexes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Modern approaches to caries management of the primary dentition.

    Science.gov (United States)

    Innes, N P T; Evans, D J P

    2013-06-01

    When prevention of dental caries fails, and a child is exposed to the risk of pain and infection, the disease must be managed to reduce this risk. There is growing evidence supporting more 'biological' and fewer 'surgical' approaches to managing dental caries in primary teeth. These biological methods include partial and stepwise caries removal procedures, as well as techniques where no caries is removed. An overview of clinical trials comparing these biological methods to complete caries removal shows that they perform as well as traditional methods and have the advantage of reducing the incidence of iatrogenic pulpal exposures. The Hall Technique is one biological approach to managing caries in primary molars which involves sealing caries beneath preformed metal (stainless steel) crowns. The crown is cemented over the tooth without caries removal, tooth preparation or use of local anaesthesia. The clinical steps for the Hall Technique are straightforward but, as with all dental care provision, appropriate treatment planning for the procedure requires skill. The Hall Technique offers another method of managing early to moderately advanced, active carious lesions in primary molars, with good evidence of effectiveness and acceptability. This evidence aligns with the positive findings of other studies on biological strategies for managing caries in primary teeth.

  13. PERMANENT-MAGNET INDUCTION GENERATORS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    K. S. S. RAMAKRISHNAN

    2011-06-01

    Full Text Available The advantage of using a permanent-magnet induction generator (PMIG instead of a conventional induction generator is its ability to suppress inrush current during system linking when synchronous input is performed. Induction machines excited with permanent-magnet (PM are called permanent-magnet induction generators. This paper presents an exhaustive survey of the literature discussing the classification of permanent-magnet machines, process of permanent-magnet excitation and voltage build-up, modelling, steady-state and performance analysis of the permanent-magnet induction generators.

  14. Manganese-based Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Ian Baker

    2015-08-01

    Full Text Available There is a significant gap between the energy product, BH, where B is the magnetic flux density and H is the magnetic field strength, of both the traditional ferrite and AlNiCo permanent magnets of less than 10 MGOe and that of the rare earth magnets of greater than 30 MGOe. This is a gap that Mn-based magnets could potentially, inexpensively, fill. This Special Issue presents work on the development of both types of manganese permanent magnets. Some of the challenges involved in the development of these magnets include improving the compounds’ energy product, increasing the thermal stability of these metastable compounds, and producing them in quantity as a bulk material.[...

  15. Automated phenotyping of permanent crops

    Science.gov (United States)

    McPeek, K. Thomas; Steddom, Karl; Zamudio, Joseph; Pant, Paras; Mullenbach, Tyler

    2017-05-01

    AGERpoint is defining a new technology space for the growers' industry by introducing novel applications for sensor technology and data analysis to growers of permanent crops. Serving data to a state-of-the-art analytics engine from a cutting edge sensor platform, a new paradigm in precision agriculture is being developed that allows growers to understand the unique needs of each tree, bush or vine in their operation. Autonomous aerial and terrestrial vehicles equipped with multiple varieties of remote sensing technologies give AGERpoint the ability to measure key morphological and spectral features of permanent crops. This work demonstrates how such phenotypic measurements combined with machine learning algorithms can be used to determine the variety of crops (e.g., almond and pecan trees). This phenotypic and varietal information represents the first step in enabling growers with the ability to tailor their management practices to individual plants and maximize their economic productivity.

  16. Clinical Application of Cone-Beam Computed Tomography of the Rabbit Head: Part 1 - Normal Dentition

    Directory of Open Access Journals (Sweden)

    GG Comet Riggs

    2016-10-01

    Full Text Available Domestic rabbits (Oryctolagus cuniculus are increasingly popular as household pets; therefore, veterinarians need to be familiar with the most common diseases afflicting rabbits including dental diseases. Diagnostic approaches for dental disease include gross oral examination, endoscopic oral examination, skull radiography, and computed tomography (CT. CT overcomes many limitations of standard radiography by permitting cross-sectional images of the rabbit head in multiple planes without superimposition of anatomic structures. Cone-beam CT (CBCT is an oral and maxillofacial imaging modality that produces high-resolution images. The objective of this study was to describe and compare the normal anatomic features of the dentition and surrounding maxillofacial structures in healthy rabbits on CBCT and conventional CT. Ten New Zealand white rabbit cadaver heads were scanned using CBCT and conventional CT. Images were evaluated using Anatomage Invivo 5 software. The maxillofacial anatomy was labeled on CBCT images and the mean lengths and widths of the teeth were determined. The visibility of relevant dental and anatomic features (pulp cavity, germinal center, tooth outline, periodontal ligament were scored and compared between conventional CT and CBCT. The thinnest teeth were the maxillary second incisor teeth at 1.29 ± 0.26 mm and the maxillary third molar teeth at 1.04 ±0.10 mm. In general, it was found that CBCT was superior to conventional CT when imaging the dentition. Importantly, the periodontal ligament was significantly (P<0.01 more visible on CBCT than on conventional CT. Ability to see the periodontal ligament with such detail may allow earlier detection and treatment of periodontal disease in rabbits. This study is the first of its kind and shows the feasibility and yield of CBCT when evaluating the maxillofacial features and dentition in rabbits.

  17. Locating Mandibular Foramen in Children with Mandibular Retrognathism in Mixed Dentition

    Directory of Open Access Journals (Sweden)

    Mehrsa Paryab

    2015-06-01

    Full Text Available Background and aims. One of the most common reasons forthe inferior alveolar nerve block anesthesia failure is the variation in mandibular foramen location. The aim of this study was to assess the location of mandibular foramen in chil-dren with mandibular retrognathism in comparison to children with normal skeletal occlusion in the mixed dentition. Materials and methods. One hundred and twenty panoramic radiographs of patients in mixed dentition period, undergo-ing orthodontic treatment, were selected based on inclusion criteria, skeletal occlusion and stage of dental development. The radiographs were divided into two groups: I: 60 panoramic radiographs of patients with normal skeletal occlusion (15 in each of the Hellman dental age stages; II: 60 panoramic radiographs of patients with mandibular retrognathism (15 in each of the Hellman dental age stages. The radiographs were traced and the linear distance from the mandibular foramen to the borders of the mandibular ramus and its angular position were identified. The measurements were compared between the two groups and among the four dental age groups by t-test, ANOVA and post hoc tests. Results. No statistically significant differences werefound between the patients with normal skeletal occlusion and patients with mandibular retrognathism (P>0.05. Statistical tests showed significant differences in the vertical location of mandibu-lar foramen and gonial angle between the four dental age groups (P<0.05. Conclusion. Mandibular retrognathism does not have a significant impact on the location of the mandibular foramen in the mixed dentition period. The child’s dental age would be considered in the localization of the mandibular foramen.

  18. Occlusal Traits of Primary Dentition among Pre-School Children of Mehsana District, North Gujarat, India

    Science.gov (United States)

    Gordhanbhai Patel, Dhvani; Ranadheer, Eraveni; Kalgudi, Jayasudha; Santokì, Jaysukh; Chaudhary, Shaila

    2017-01-01

    Introduction Aesthetic and functional problems in the dentofacial complex among children are often attributed to the disturbances in the dentofacial growth and development. This can be recognized during routine dental visits. This study pursued to assess the occlusion of the primary dentition in three to five-year-old children. Aim To study the occlusal traits of the primary dentition in a group of three to five-year-old North Gujarat children of Mehsana district and the variation in their occlusion relative to age and gender in the same group. Materials and Methods The study was a cross-sectional survey based on clinical examination and photographic evaluation of the primary dentition, 383 preschool children aged three to five years who were randomly selected from preschools in Mehsana district, Gujarat, India, using a multistage sampling technique. The study group was evaluated for the several occlusal parameters that include primary molar relation based on Baume classification and canine relation, overjet, overbite were assessed using Foster and Hamilton criteria. Chi-square test was performed to carry out statistical analysis. The p-value<0.05 was taken as statistically significant. Results Out of 383 participants, 55.35% had flush terminal plane; 43.34% mesial step molar relationship and 1.31% distal step molar relationship, 63.2% had straight profile, 95.8% had Class I canine relationship, 71.3% primate spaces, 56.7% physiologic spaces. Flush terminal plane was common at three years while, mesial step at four to five years, and Class I canine relationship was prevalent in both age groups. Flush terminal plane was more common in female participants than the males. Amongst other occlusal characteristics, increased overbite and open bite were prevalent. Conclusion It was found that the flush terminal plane molar relationship, straight profile, Class I canine relationship, primate spacing, increased overbite and open bite predominated. PMID:28274054

  19. Specializations of the mandibular anatomy and dentition of Segnosaurus galbinensis (Theropoda: Therizinosauria

    Directory of Open Access Journals (Sweden)

    Lindsay E. Zanno

    2016-03-01

    Full Text Available Definitive therizinosaurid cranial materials are exceptionally rare, represented solely by an isolated braincase and tooth in the North American taxon Nothronychus mckinleyi, the remarkably complete skull of the Asian taxon Erlikosaurus andrewsi, and the lower hemimandibles of Segnosaurus galbinensis. To date, comprehensive descriptions of the former taxa are published; however, the mandibular materials of S. galbinensis have remained largely understudied since their initial description in 1979. Here we provide a comprehensive description of the well-preserved hemimandibles and dentition of S. galbinensis (MPC-D 100/80, from the Upper Cretaceous Bayanshiree Formation, Gobi Desert, Mongolia. The subrectangular and ventrally displaced caudal hemimandible, extreme ventral deflection of the rostral dentary, and edentulism of the caudal dentary of S. galbinensis are currently apomorphic among therizinosaurians. Unique, unreported dental traits including lingually folded mesial carinae, development of a denticulated triangular facet on the distal carinae near the cervix, and extracarinal accessory denticles, suggest a highly specialized feeding strategy in S. galbinensis. The presence of triple carinae on the distalmost lateral tooth crowns is also unique, although may represent an abnormality. Contrasted with the simplistic dentition of the contemporaneous therizinosaurid E. andrewsi, the dentition of S. galbinensis is indicative of niche partitioning in food acquisition, processing, or resources among known therizinosaurids inhabiting Asian ecosystems in the Late Cretaceous. Although not quantitatively correlated with diet, this suite of specializations is otherwise unique among theropod dinosaurs and supports derived inferences of facultative or obligate herbivory in therizinosaurids, ultimately adding novel information to our understanding of ecomorphology in theropods.

  20. Trans-permanent magnetic actuation

    Science.gov (United States)

    Farmer, Daniel Jay

    The demands for an actuator to deploy, position and shape large spaced-based structures form a unique set of design criteria. In many applications it is desirable to hold displacements or forces between two points to within specified requirements (the regulation problem) and to periodically to change position (the tracking problem). Furthermore, the interest generally lies in satisfying the dynamic performance requirements while expending minimal power, while meeting tight tolerances and while experiencing little wear and fatigue. The actuator must also be able to withstand a variety of operational conditions such as impacts and thermal changes over an extended period of time. Current trends in large-scale structures have addressed the demands by using conventional actuators and motors, along with elaborate linkages or mechanisms to shape, position, protect and deploy. The developed designs use unique characteristics of permanent magnets to create simple direct-acting actuators and motors very suitable for space based structures. The developed trans-permanent magnetic (T-PM) actuators and motors are systems consisting of one or more permanent magnets, some of whose magnetic strengths can be switched on-board by surrounding pulse-coils. The T-PM actuator and motors expend no power during regulation. The T-PM can periodically change or remove the strength of its own magnets thereby enabling both fine-tune adjustments (microsteps) and large-scale adjustments (rotation). The fine (microstep) adjustments are particularly helpful in thermally varying space environments. The large-scale adjustments (rotation) are particularly helpful in deployment where the structure or antenna must experience large-angle rotations and/or large displacements. T-PM concepts are illustrated in direct acting actuators and built into stepper motor and permanent magnet motor applications. Several examples of design, analysis and testing are developed to verify the technology and supporting

  1. The cycloid Permanent Magnetic Gear

    DEFF Research Database (Denmark)

    Rasmussen, Peter Omand; Andersen, Torben Ole; Jørgensen, Frank T.

    2008-01-01

    This paper presents a new permanent-magnet gear based on the cycloid gearing principle. which normally is characterized by an extreme torque density and a very high gearing ratio. An initial design of the proposed magnetic gear was designed, analyzed, and optimized with an analytical model...... regarding torque density. The results were promising as compared to other high-performance magnetic-gear designs. A test model was constructed to verify the analytical model....

  2. The periodontal prosthesis mode of transition to an implant-supported dentition.

    Science.gov (United States)

    Hunt, Peter; Norkin, Frederic; Serrano, Julian

    2006-01-01

    In recent years, implant-supported reconstructions have become a welcome alternative to dentures for those who have lost their natural dentition. While the benefits of the final implant-supported reconstruction may be obvious, the planning and execution of therapy to achieve this result may be bewildering to many dentists. Four main modes of transfer have evolved: an uncontrolled or "haphazard" transition; the traditional "dentures first" mode, an immediate transition, and a staged transition. This article proposes an additional mode of transition called periodontal prosthesis, which has the potential to make the transition process smoother and more predictable while providing optimal retention of alveolar supporting structures and generating optimal esthetics.

  3. Evaluation of facial morphology and sagittal relationship between dental arches in primary and mixed dentition.

    Science.gov (United States)

    Traldi, Aline; Valdrighi, Heloísa Cristina; de Souza, Luciane Zanin; Vedovello, Silvia Amélia Scudeler

    2015-01-01

    To assess facial morphology (Pattern) and sagittal relationship between dental arches (Class), and establish a potential association between them and the variables sex, age and ethnicity, among schoolchildren aged between 4 and 9 years old (mean age of 6.7 years) in primary and mixed dentitions. The sample comprised 875 children (457 males and 418 females) attending schools in Descalvado, São Paulo, Brazil. An attempt was made with a view to establish a potential association between children's morphological features with sex, age and ethnicity. Descriptive analysis revealed a predominance of facial Pattern I (69.9 %) and Class I (67.4 %). Statistical tests (p Afro-descendant subjects.

  4. Prosthodontic Rehabilitation of the Patient with Severely Worn Dentition: A Case Report

    Directory of Open Access Journals (Sweden)

    Mahnaz Hatami

    2012-01-01

    Full Text Available The management of tooth wear has been a subject of increasing interest from both preventive and restorative points of view. This paper describes the full mouth rehabilitation of a 63-year-old bruxer man with a severely worn dentition and other dental problems including unsuitable restorations and several missing teeth. The treatment entailed using cast posts and cores, metal-ceramic restorations, and a removable partial denture. As with the treatment procedure of such cases, equal-intensity centric occlusal contacts on all teeth and an anterior guidance in harmony with functional jaw movements were especially taken into account.

  5. Prosthodontic rehabilitation of a bruxer patient with severely worn dentition: a clinical case report

    Directory of Open Access Journals (Sweden)

    Farhang Mahboub

    2009-03-01

    Full Text Available The management of tooth wear has been a subject of increasing interest from both preventive and restorative points of view. This article describes the full mouth rehabilitation of a 54-year-old bruxer woman with a severely worn dentition and other dental problems including unsuitable restorations and several missing teeth. The treatment entailed using cast posts and cores, metal-ceramic restorations, and a removable partial denture. As with the treatment procedure of such cases, equal-intensity centric occlusal contacts on all teeth and an anterior guidance in harmony with functional jaw movements were especially taken into account.

  6. Permanent magnets including undulators and wigglers

    OpenAIRE

    Bahrdt, J.

    2011-01-01

    After a few historic remarks on magnetic materials we introduce the basic definitions related to permanent magnets. The magnetic properties of the most common materials are reviewed and the production processes are described. Measurement techniques for the characterization of macroscopic and microscopic properties of permanent magnets are presented. Field simulation techniques for permanent magnet devices are discussed. Today, permanent magnets are used in many fields. This article concentrat...

  7. Analysis of 156 primary scholar's caries during mixed dentition%156例替牙期小学生龋病相关因素分析

    Institute of Scientific and Technical Information of China (English)

    李奉华; 刘虹; 阙国鹰; 翦新春; 彭解英; 米大丽

    2006-01-01

    目的了解替牙期小学生龋坏的影响因素,为制定预防措施提供依据.方法随机抽取以8~10岁为主的小学生156名,分析恒、乳牙龋坏与年龄、性别、软垢等因素的相关性.结果患龋率以9岁组最高,但年龄和性别差异无统计学意义.软垢指数年龄和性别差异无统计学意义.有乳牙龋坏的软垢指数明显高于无乳牙龋坏者,差异有统计学意义.多因素分析表明:在乳牙龋坏过程中,年龄、软垢对其影响较大.结论为有效防止8~10岁小学生乳牙龋坏,加强口腔卫生知识宣教、控制软垢、定期检查和预防治疗是关键.%[Objective] To assess the effect of factors in primary scholar's caries during mixed dentition, so as to take pertinent measures to prevent caries. [Mothods] 156 primary scholars, who were mainly aged 8~10, were selected randomly, then the correlation between caries of deciduous and permanent teeth and age, sex, food debris was analyzed by single and multiple factor statistical analysis. [Results] The prevalence rate of caries in group of age 9was the highest than that in other age groups. There was no statistical significance among age (8,9,10) groups and between sex (male, female) groups in prevalence rate. There was no statistical significance among age (8,9,10) groups and between sex (male, female)groups in debris index(DI). There was statistical significance in debris index (DI) between primary scholars with caries of deciduous teeth and those without it. Multiple factor statistical analysis showed:age and debris were the main factors inducing caries of deciduous teeth. [Conclusion] In order to prevent primary scholar's caries during mixed dentition effectively, oral healthcare education, eliminating food debris, regular check and prophylactic treatment are crucial.

  8. 21 CFR 886.4445 - Permanent magnet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Permanent magnet. 886.4445 Section 886.4445 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove...

  9. Evaluation of salivary mucins in children with deciduous and mixed dentition: comparative analysis between high and low caries-risk groups

    NARCIS (Netherlands)

    Angwaravong, O.; Pitiphat, W.; Bolscher, J.G.M.; Chaiyarit, P.

    2015-01-01

    Objectives The aim of this study was to examine levels of salivary mucins in children with deciduous and mixed dentition and to determine correlations between salivary mucins and dental caries status in two dentition stages. Materials and methods Saliva samples were collected from preschool children

  10. First complete sauropod dinosaur skull from the Cretaceous of the Americas and the evolution of sauropod dentition

    Science.gov (United States)

    Chure, Daniel; Britt, Brooks B.; Whitlock, John A.; Wilson, Jeffrey A.

    2010-04-01

    Sauropod dinosaur bones are common in Mesozoic terrestrial sediments, but sauropod skulls are exceedingly rare—cranial materials are known for less than one third of sauropod genera and even fewer are known from complete skulls. Here we describe the first complete sauropod skull from the Cretaceous of the Americas, Abydosaurus mcintoshi, n. gen., n. sp., known from 104.46 ± 0.95 Ma (megannum) sediments from Dinosaur National Monument, USA. Abydosaurus shares close ancestry with Brachiosaurus, which appeared in the fossil record ca. 45 million years earlier and had substantially broader teeth. A survey of tooth shape in sauropodomorphs demonstrates that sauropods evolved broad crowns during the Early Jurassic but did not evolve narrow crowns until the Late Jurassic, when they occupied their greatest range of crown breadths. During the Cretaceous, brachiosaurids and other lineages independently underwent a marked diminution in tooth breadth, and before the latest Cretaceous broad-crowned sauropods were extinct on all continental landmasses. Differential survival and diversification of narrow-crowned sauropods in the Late Cretaceous appears to be a directed trend that was not correlated with changes in plant diversity or abundance, but may signal a shift towards elevated tooth replacement rates and high-wear dentition. Sauropods lacked many of the complex herbivorous adaptations present within contemporaneous ornithischian herbivores, such as beaks, cheeks, kinesis, and heterodonty. The spartan design of sauropod skulls may be related to their remarkably small size—sauropod skulls account for only 1/200th of total body volume compared to 1/30th body volume in ornithopod dinosaurs.

  11. [Simplified oral hygiene index for ages 4 to 6 and 7 to 10 (deciduous and mixed dentition)].

    Science.gov (United States)

    Rodrigues, C R; Ando, T; Guimarães, L O

    1990-01-01

    The purpose of this research is to obtain simplified index to evaluate oral hygiene in children. They are divided in two groups: 1) 4-6 years and; 2) 7-10 years. The criteria described by GREEN & VERMILLION, 1960 and 1964 were selected. Calculus was excluded. Once obtained the total data, a simplified of the total index was performed. For the ages 4 to 6 years, we selected labial surfaces of the 54, 61, 82 and the lingual surface of 75. For the mixed dentition we added the labial surface of 26 and the lingual surface of 46. In both dentition, simplified index showed significant correlation with the total index.

  12. Occlusal traits of deciduous dentition of preschool children of Indian children

    Directory of Open Access Journals (Sweden)

    Rakesh N Bahadure

    2012-01-01

    Full Text Available Objectives: To assess the occlusal relationship, canine relationship, crowding, primate spaces, and anterior spacing in both maxillary and mandibular arches of primary dentition of Indian children of Wardha District and also to study the age-wise differences in occlusal characteristics. Materials and Methods: A total of 1053 (609 males and 444 females children of 3-5 year age group with complete primary dentition were examined for occlusal relationship, canine relationship, crowding, primate spaces, and anterior spacing in both maxillary and mandibular arches. Results: The data after evaluation showed significant values for all parameters except mandibular anterior spacing, which was 47.6%. Mild crowding was prevalent at 5 year age group and moderate crowding was common at 3 year-age group. Conclusion: Evaluated parameters such as terminal molar relationship and canine relationship were predominantly progressing toward to normal but contacts and crowding status were contributing almost equal to physiologic anterior spacing. Five-year-age group showed higher values with respect to all the parameters.

  13. Management of an Adult with Spaced Dentition, Class III Malocclusion and Open-bite Tendency.

    Science.gov (United States)

    Kaya, Demet; Taner, Tulin Ugur

    2011-01-01

    The aim of this case report was to present the orthodontic treatment of an adult with spaced dentition, Class III malocclusion, and open-bite tendency. A 28.4-year-old adult woman was concerned about the unesthetic appearance of her spaced dentition localized at both upper and lower arches while smiling. She had a mild tongue thrust, hypertropic upper frenum, and mild speech difficulty while pronouncing "s". Her profile was straight with prominent lips. Molar relationship was Class III on both sides. Anterior teeth were in an end-to-end relationship. Lower dental midline was deviated to the left side. Cephalometric analysis revealed a skeletal Class III relationship with hyperdivergent facial pattern. The treatment plan included myotherapeutic exercises for the tongue thrust habit and a diagnostic set-up for closure of diastemas. A strict retention protocol was followed combined with gingivoplasty, fiberotomy, and frenectomy procedures. All spaces were closed successfully, adequate overbite and overjet relationships were obtained, and tongue thrust habit and speech difficulty while pronouncing "s" were eliminated. Clinical and cephalometric results indicated the maintenance of the treatment outcome at 6-months post-retention period.

  14. Aesthetic and Functional Rehabilitation of the Primary Dentition Affected by Amelogenesis Imperfecta

    Directory of Open Access Journals (Sweden)

    Maria Carolina Salomé Marquezin

    2015-01-01

    Full Text Available The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars with stainless steel crowns and resin-filled celluloid forms. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function, and eliminate the teeth sensitivity. The child was monitored in the pediatric dentistry clinic at four-month intervals until the mixed dentition stage. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life. The preventive, psychological, and curative measures of a young child with AI were successful. This result can encourage the clinicians to seek a cost-effective technique such as stainless steel crowns, and resin-filled celluloid forms to reestablish the oral functions and improve the child’s psychosocial development.

  15. The role of orthodontics in the regeneration of the degenerated dentition.

    Science.gov (United States)

    Melsen, B

    2016-03-01

    The demand for regeneration of a degenerated dentition has been increasing as a result of the development of societies, where the life expectancy is increasing and fighting age-related changes is in focus. Whereas removable dentures were acceptable and considered a norm earlier, patients do, to an increasing degree,demand fixed prosthetics; consequently, the development of implants has had an important impact. The balance in the chewing organ will change with time, due to age-related changes within the bone and the loss of teeth due to caries or periodontal disease, and malocclusions may develop or aggravate. The re-establishment of an aesthetical and functional satisfactory solution cannot be reached by replacing teeth by fixed prosthodontics and implants. The aim of this update was threefold: firstly, to demonstrate that age-related changes, often unnoticed by both the patient and the general dentist, can lead to degeneration of the dentition; secondly, to explain how an interdisciplinary approach can make regeneration of even severe degeneration possible; and finally, to show the importance of the general dentist in the maintenance of the obtained results. Treatments should not aim for short-term results but focus on maintainable results. © 2015 John Wiley & Sons Ltd.

  16. [State of dentition and its impact on the capacity of elders to perform daily activities].

    Science.gov (United States)

    Sánchez-García, Sergio; Juárez-Cedillo, Teresa; Reyes-Morales, Hortensia; de la Fuente-Hernández, Javier; Solórzano-Santos, Fortino; García-Peña, Carmen

    2007-01-01

    The aim of this study was to evaluate the effect of dental state on the capacity of elderly individuals to carry out their daily activities during the previous six months. A transversal study was conducted in the Mexican Institute of Social Security (IMSS) with insured elderly persons residing in southwestern Mexico City. Home interviews were conducted to gather sociodemographic data, data on the use of oral health services, problems in carrying out daily activities, and their relationship with the state of dentition over the past six months, utilizing the Oral Impacts on Daily Performance (OIDP) index. Later, three oral health professionals trained in determining the state of dentition according to World Health Organization (WHO) criteria performed a clinical examination on each elderly subject. A total of 540 elderly individuals were studied. The prevalence of elderly persons with problems in carrying out their daily activities was 21.5%. The main problems in daily activities were eating (14.4%), speaking (8.7%), not becoming irritated (5.4%), brushing their teeth(5%), and inability to enjoy contact with people (4.4%). There is a positive OIDP correlation between number of teeth lost and the decayed, missing, filled teeth(DMFT) index (ppronunciation.

  17. Osteoarthrosis of Temporomandibular Joint Related to the Defects of Posterior Dentition: A Retrospective Study.

    Science.gov (United States)

    Levorová, Jitka; Machoň, Vladimír; Guha, Anasuya; Foltán, René

    2016-01-01

    Osteoarthrosis (OA) of temporomandibular joint (TMJ) is a progressive degenerative disease, gradually affecting cartilage, synovial membrane and bone structures. OA of TMJ clinically manifests with joint noises, pain and restricted mouth opening. In late stages, it results in severe damage of TMJ structures and development of ankylosis. Osteoarthrosis is a multifactorial disease; the occurrence is associated with TMJ overloading. The cohort included 619 patients [538 women (87%) and 81 men (13%), with average age 40.6 years (age range 8-89 years)] with TMJ disorder, who were examined in the year 2014 in Department of Dental Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Czech Republic. The aim of this retrospective study was to analyse, if the lack of posterior teeth (supporting teeth zones) is the main etiologic factor of osteoarthrosis of TMJ. Diagnosis of OA was established on the clinical signs and the panoramic X-ray signs. Simultaneously other etiologic factors of OA were assessed. The presence of OA changes on X-ray had 171 patients (i.e. 27.6% of the total number of 619). 17.5% from these patients with OA had defect in posterior dentition. Other aetiological factors (stress, skeletal or vertebrogenous disorders) showed higher incidence of OA changes on X-ray. Defect of posterior dentition is not negligible, but it is not the main aetiological factor for osteoarthrosis of TMJ.

  18. Comparison of Endoflas and Zinc oxide Eugenol as root canal filling materials in primary dentition

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    Nivedita Rewal

    2014-01-01

    Full Text Available Background: Zinc oxide eugenol has long been the material of choice of pediatric dentists worldwide, although it fails to meet the ideal requirements of root canal filling material for primary teeth. Endoflas, a mixture of zinc oxide eugenol, calcium hydroxide, and iodoform, can be considered to be an effective root canal filling material in primary teeth as compared with zinc oxide eugenol. This study was carried out to compare zinc oxide eugenol with endoflas for pulpectomy in primary dentition. Aim: The objective of the study was to compare clinically and radiographically success rates of zinc oxide eugenol with endoflas for the root canal filling of primary teeth at 3, 6, and 9 months. Design: Fifty primary molars were included in the study with 26 teeth in Group I (Endoflas and 24 in Group II (zinc oxide eugenol. A single visit pulpectomy was carried out. Results: The overall success rate of zinc oxide eugenol was 83% whereas 100% success was found in the case of endoflas. The obtained results were compiled and subjected to statistical analysis using the chi-square test. The difference in the success rate between the two was statistically significant (P < 0.05. Conclusion: Endoflas has shown to have better results than zinc oxide eugenol. It should therefore be the material of choice for root canal treatment in deciduous dentition.

  19. Tooth replacement and putative odontogenic stem cell niches in pharyngeal dentition of medaka (Oryzias latipes).

    Science.gov (United States)

    Abduweli, Dawud; Baba, Otto; Tabata, Makoto J; Higuchi, Kazunori; Mitani, Hiroshi; Takano, Yoshiro

    2014-04-01

    The small-sized teleost fish medaka, Oryzias latipes, has as many as 1000 pharyngeal teeth undergoing continuous replacement. In this study, we sought to identify the tooth-forming units and determine its replacement cycles, and further localize odontogenic stem cell niches in the pharyngeal dentition of medaka to gain insights into the mechanisms whereby continuous tooth replacement is maintained. Three-dimensional reconstruction of pharyngeal epithelium and sequential fluorochrome labeling of pharyngeal bones and teeth indicated that the individual functional teeth and their successional teeth were organized in families, each comprising up to five generations of teeth and successional tooth germs, and that the replacement cycle of functional teeth was approximately 4 weeks. BrdU label/chase experiments confirmed the existence of clusters of label-retaining epithelial cells at the posterior end of each tooth family where the expression of pluripotency marker Sox2 was confirmed by in situ hybridization. Label-retaining cells were also identified in the mesoderm immediately adjacent to the posterior end of each tooth family. These data suggest the importance of existence of slow-cycling dental epithelial cells and Sox2 expressions at the posterior end of each tooth family to maintain continuous tooth formation and replacement in the pharyngeal dentition of medaka.

  20. Psychophysiological support of orthopedic treatment in patients with dento-alveolar form of dentition and occlusion

    Directory of Open Access Journals (Sweden)

    Razakov D.Kh.

    2013-09-01

    Full Text Available The purpose: to improve the treatment of patients with orthopedic dento-alveolar deformation of dentition and occlusion by using a range of methods of psychophysiological support of patient care. Material and methods. The study included 86 patients, men and women aged from 18 to 49 years with dento-alveolar deformation of dentition and occlusion. The study used clinical, anthropometric, radiological, photometric and static methods. At each stage of treatment, to investigate the characteristics of the functional status of patients methods of SAN, IPC «adaptive», self-esteem of patients by developed questionnaire were used. Results. A direct, reliable, moderate correlation has been established between the estimates that have given quality of care to patients with a regularity of the complex of psychophysiological methods proposed. Conclusion. A positive impact of the proposed complex of psychophysiological methods to support the functional characteristics of the patients and their assessment of the treatment, and the effectiveness of orthopedic treatment have been determined.

  1. The mesiodistal crown diameters of primary dentition in Indonesian Javanese children.

    Science.gov (United States)

    Kuswandari, Sri; Nishino, Mizuho

    2004-03-01

    Dentition analysis of primary teeth is necessary for recognising and correcting occlusal problems in every stage of dental development to enable normal adult occlusion. To do this, normative data of mesiodistal tooth crown diameters from the same ethnic population are needed. The aims of this study were to gather normative data of mesiodistal crown diameters of primary dentition in Indonesian Javanese children and to compare this normative data with published data of other ethnic populations. Dental casts of 160 males and 137 females with acceptable occlusion, aged 3.25-6.58 years, were taken in Yogyakarta, Indonesia. Mesiodistal diameter was measured as the distance between the anatomic contact points using calipers with accuracy to within 0.05 mm. Each measurement was taken twice on different occasions. The results indicated that the magnitude of asymmetry between right and left teeth was larger in distal teeth within a tooth field, larger in males than females, and larger in mandibular than maxillary teeth. The stability of mesiodistal tooth crown diameters was less in males than in females, and was most prominent in the mandibular central incisor. Sexual dimorphisms were found in, the lateral incisor and first molar in the maxilla, and the canine, first and second molars in the mandible. Compared with other ethnic populations, Indonesian Javanese falls between Hong Kong Chinese and Australian Aboriginal.

  2. Breastfeeding, Bottle Feeding Practices and Malocclusion in the Primary Dentition: A Systematic Review of Cohort Studies

    Directory of Open Access Journals (Sweden)

    Ana Paula Hermont

    2015-03-01

    Full Text Available The World Health Organization recommends exclusive breast feeding for at least six months. However, there is no scientific evidence of the benefits of breast feeding for oral health in children under primary dentition. This study aimed to search for scientific evidence regarding the following question: is bottle feeding associated with malocclusion in the primary dentition compared to children that are breastfed? An electronic search was performed in seven databases. The systematic review included 10 cohort studies. It was not possible to conduct meta-analysis; therefore a qualitative analysis was assessed. The majority of studies evaluated feeding habits by means of questionnaires and conducted a single examination. Three studies observed that bottle feeding was significantly associated with overjet and posterior crossbite. Studies reported several cut-off times for breastfeeding (varying from 1 month up to 3 years of age and several types of malocclusion. Controlling for non-nutritive sucking habits was reported for only half of the studies and this may have led to biased results. The scientific evidence could not confirm a specific type of malocclusion associated with the feeding habits or an adequate time of breastfeeding to benefit the children against malocclusion. Further cohort studies are needed to confirm this evidence.

  3. Breastfeeding, bottle feeding practices and malocclusion in the primary dentition: a systematic review of cohort studies.

    Science.gov (United States)

    Hermont, Ana Paula; Martins, Carolina C; Zina, Lívia G; Auad, Sheyla M; Paiva, Saul M; Pordeus, Isabela A

    2015-03-16

    The World Health Organization recommends exclusive breast feeding for at least six months. However, there is no scientific evidence of the benefits of breast feeding for oral health in children under primary dentition. This study aimed to search for scientific evidence regarding the following question: is bottle feeding associated with malocclusion in the primary dentition compared to children that are breastfed? An electronic search was performed in seven databases. The systematic review included 10 cohort studies. It was not possible to conduct meta-analysis; therefore a qualitative analysis was assessed. The majority of studies evaluated feeding habits by means of questionnaires and conducted a single examination. Three studies observed that bottle feeding was significantly associated with overjet and posterior crossbite. Studies reported several cut-off times for breastfeeding (varying from 1 month up to 3 years of age) and several types of malocclusion. Controlling for non-nutritive sucking habits was reported for only half of the studies and this may have led to biased results. The scientific evidence could not confirm a specific type of malocclusion associated with the feeding habits or an adequate time of breastfeeding to benefit the children against malocclusion. Further cohort studies are needed to confirm this evidence.

  4. Material selection for prosthetics of defects of dentitions at patients with functional and inflammatory bowel diseases

    Directory of Open Access Journals (Sweden)

    Myalina Yu.N.

    2012-06-01

    Full Text Available Objective: To study clinical-morphological characteristics of parodontal diseases, markers of density of bone tissue and to define rational approaches to prosthetics of defects of dentitions in patients with colon diseases. Materials and methods: 55 patients with ulcerative colitis, even 80 with the syndrome of the irritable bowel syndrome with defects of dentitions, have been applied metallic, cement prostheses and having prostheses on the intraosseous of implants. Markers of bone metabolism in the blood serum and in the oral liquid, the proliferating activity of the epitheliocytes of periodontium have been evaluated according to the morphometric indices of the markers of the proliferation of ki-67, cyclein D1, the inhibitor of apoptosis of bcl-2 have been inspected. Results: Connection of intensity of periodontitis with the stage of colon disease has been stated. Metallic dental prostheses have been served as additional risk factors of development of parodontal diseases in patients with ulcerative colitis. Conclusion: The diagnostic value of the markers of proliferation has been determined in diagnostics of parodontal disease during the application of prostheses from different materials.

  5. Permanent-File-Validation Utility Computer Program

    Science.gov (United States)

    Derry, Stephen D.

    1988-01-01

    Errors in files detected and corrected during operation. Permanent File Validation (PFVAL) utility computer program provides CDC CYBER NOS sites with mechanism to verify integrity of permanent file base. Locates and identifies permanent file errors in Mass Storage Table (MST) and Track Reservation Table (TRT), in permanent file catalog entries (PFC's) in permit sectors, and in disk sector linkage. All detected errors written to listing file and system and job day files. Program operates by reading system tables , catalog track, permit sectors, and disk linkage bytes to vaidate expected and actual file linkages. Used extensively to identify and locate errors in permanent files and enable online correction, reducing computer-system downtime.

  6. The effect of unerupted permanent tooth crowns on the distribution of masticatory stress in children.

    Directory of Open Access Journals (Sweden)

    Ashley S Hammond

    Full Text Available Human mothers wean their children from breast milk at an earlier developmental stage than do ape mothers, resulting in human children chewing solid and semi-solid foods using the deciduous dentition. Mechanical forces generated by chewing solid foods during the post-weaning period travel through not only the deciduous teeth, but also the enamel caps of the developing permanent teeth within the maxilla and mandible, which are not present in the adult face. The effects of mechanical stress propagating through these very stiff structures have yet to be examined. Based on a heuristic model, we predicted that the enamel of the embedded developing teeth would act to reduce stresses in the surrounding bony elements of the juvenile face. We tested this hypothesis by simulating occlusal loading in a finite element (FE model of a child's cranium with a complete set of deciduous teeth and the first permanent molars embedded in the bony crypt in the maxilla. We modeled bone and enamel with appropriate material properties and assessed the effect of embedding high-stiffness enamel structures on stress distribution in the juvenile face. Against expectation, the presence of unerupted enamel caps does not affect the magnitude or location of stresses in the juvenile face. Our results do not support the hypothesis that the unerupted secondary teeth act to moderate stresses in the juvenile face.

  7. Continued Root Formation after Delayed Replantation of an Avulsed Immature Permanent Tooth

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    Nima Moradi Majd

    2014-01-01

    Full Text Available Introduction. Tooth avulsion in the young permanent dentition is a frequent finding, and its prognosis depends on the treatment of the avulsed tooth before replantation, the extra-alveolar time, the storage medium, and the patient’s general health. The present report describes management of an immature avulsed lower central incisor 90 minutes after the accident. Methods. A right lower central incisor of a 7-year-old girl was avulsed, and it was soaked in a glass of milk. 90 minutes after avulsion, replantation was performed, and the tooth was splinted; but after two weeks the replanted tooth’s pulp was necrotic. Thus, endodontic treatment was performed and root canal was filled using a calcium hydroxide and iodoform paste (Metapex. Three months later, the intracanal medication was washed out and the canal was sealed using an apical plug of calcium enriched mixture (CEM cement. Results. 20 months after replantation the tooth was completely asymptomatic, with physiologic mobility. Also, continued root formation including an apical segment beyond the artificial apical plug was observed. Conclusion. Creation of an appropriate apical barrier following the disinfection of root canal system promoted continued root-end growth in a replanted immature permanent tooth.

  8. Holistic care patient with Early Childhood Caries (ECC: A case report

    Directory of Open Access Journals (Sweden)

    Intan Maulani

    2016-06-01

    Full Text Available Early Childhood Caries (ECC is a specific form of severe dental caries that affects infants and young children. ECC progresses rapidly in those who are at high risk, and often goes untreated. Children experiencing caries as infants or toddlers have a much greater probability of subsequent caries in both primary and permanent dentitions. This case showed management holistic care for children with ECC.A five year old boy patient accompanied with her parents were reported to the Pedodontic Clinic Padjadjaran University Dental Hospital with a chief complaint of decayed upper anterior teeth and pain in the molar teeth. Clinical examinations found dental caries almost all teeth in the maxilla and mandible. Based on panoramic radiograph, treatments that can be done are strip crown glass ionomer restorations, pulp treatments, extractions and fixed space maintainer. Patients diagnosed with severe ECC, patient and parents described on this type of caries. During treatment the patient was given oral hygiene instruction and recommend daily use of tooth mouse. After all treatment were completed, fluoride topical, and fissure sealants, recall check up after three months was scheduled. Holistic care needed in handling children with ECC.

  9. CERN Permanent exhibitions short version

    CERN Multimedia

    2016-01-01

    Visits Explore by yourself the issues CERN's physicists are trying to solve: given that the entire universe is made of particles, where do they come from? Why do they behave in the way they do? Discover the massive apparatus used by physicists at CERN, like the LHC, and see how each part works. CERN invites the public to discover the mysteries of the Universe and the work of the world's biggest physics laboratory through free of charge guided tours and permanent exhibitions. As a group, with friends, individually, on foot, on your bike, come and discover CERN or explore it virtually. Welcome!

  10. Koreksi dimensi vertikal oklusal dengan modifikasi restorasi mahkota logam pada kasus severe early childhood caries (Correcting occlusal vertical dimension using modified stainless steel crown restoration in severe early childhood caries case

    Directory of Open Access Journals (Sweden)

    Amrita Widyagarini

    2014-06-01

    Full Text Available Background: Severe early childhood caries (SECC describes progressively dental caries in primary dentition among children aged less than 3 to 5-year-old. Loss of Occlusal Vertical Dimension (OVD with deep bite in clinical feature found 2.5 times more often in s-ecc children than others. It leads discrepancies of vertical development of permanent dentition, hence creates malocclusion. Purpose: The aim of this paper was to report consideration and correction of OVD in SECC child. Case: A 5-year-old girl was accompanied by her mother came to pediatric dental clinic Faculty of Dentistry Universitas Indonesia. Patient’s chief complaint was decay on all her teeth. Clinical examination revealed caries on all primary dentition, tooth #16, #46 have not yet been occluded, 26 erupted partially and it occluded with 36, anterior deep bite. Diagnose was anterior deep bite caused by SECC. Case management: Operative-rehabilitative treatment restores OVD to prevent malocclusion by modifying height of ssc in primary molars. Correcting deep bite using stainless steel crown (SSC modified in posterior was done. First, restoration with glass-ionomer cement for raising the bite followed by a week evaluation to observe masticatory function and functional analysis of temporomandibular joint. Second, ssc were placed in primary molars. Conclusion: Modifying height of ssc in primary molars could corrected OVD in SECC child. Permanent first molars eruption could be guided to completely occlusion and prevent early malocclusion.Latar belakang: Severe early childhood caries (SECC menunjukan pola karies gigi sulung yang progresif dan menyeluruh pada anak usia di bawah 3 hingga 5 tahun. Kehilangan dimensi vertikal oklusal (DVO, dengan gambaran gigitan dalam pada periode gigi sulung dilaporkan terjadi 2,5 kali lebih banyak pada anak SECC. Hal ini dapat menyebabkan gangguan perkembangan vertikal gigi permanen yang nantinya menyebabkan maloklusi. Tujuan: Laporan kasus ini

  11. Dental fluorosis in children in areas with fluoride-polluted air, high-fluoride water, and low-fluoride water as well as low-fluoride air: A study of deciduous and permanent teeth in the Shaanxi province, China

    Energy Technology Data Exchange (ETDEWEB)

    Ruan, J.P.; Bardsen, A.; Astrom, A.N.; Huang, R.Z.; Wang, Z.L.; Bjorvatn, K. [University of Bergen, Bergen (Norway). Dept. of Oral Science

    2007-07-01

    The aim of the study was to assess dental fluorosis (DF) in the deciduous and permanent teeth of children in areas with high-F coal (area A) and high-F water (area C) compared to children from area B, with low-F water and coal. DF was found to be prevalent in both dentitions in areas A and C. Similarity in percentages of DF may indicate that indoor air with about to 60 {mu}g F/m{sup 3} and drinking water with 3.6 mg F/L are similarly toxic to developing permanent teeth. The percentage of deciduous teeth with DF was significantly lower in area A compared to area C. Where low-F coal and low-F water were used (area B), similar to 20% of permanent teeth had DF, indicating a relatively low tolerance to fluoride in Chinese children brought up under the present living conditions.

  12. Bone Reduction to Facilitate Immediate Implant Placement and Loading Using CAD/CAM Surgical Guides for Patients With Terminal Dentition.

    Science.gov (United States)

    Alzoubi, Fawaz; Massoomi, Nima; Nattestad, Anders

    2016-10-01

    The aim of this study is to present a method, using 3 computer-aided design/computer-aided manufacturing (CAD/CAM) surgical guides, to accurately obtain the desired bone reduction followed by immediate implant placements and loading for patients diagnosed with terminal dentition. Patients who had bone reduction, implants placed, and immediate loading using Anatomage Invivo 5 CAD/CAM surgical guides between the period 2013 and 2015 were evaluated retrospectively. Patients diagnosed with terminal dentition and treated using the "3-guide technique" were identified. Pre- and postsurgical images were superimposed to evaluate deviations of the bone reduction and deviations at the crest, apex, and angle of implants placed. Twenty-six implants placed in 5 patients were included in this study. The overall deviation means measured for bone reduction was 1.98 mm. The overall deviation means measured for implant placement at the crest, apex, and angle were 1.43 mm, 1.90 mm, and 4.14°, respectively. The CAD/CAM surgical guide fabrication is an emerging tool that may facilitate the surgical process and aid in safe and predictable execution of bone reduction and immediate implant placement. Using 3 CAD/CAM surgical guides, a method is presented to obtain the desired bone reduction followed by immediate implant placement and loading for patients diagnosed with terminal dentition. This method may improve guide stability for patients with terminal dentition undergoing complete implant-supported treatment by taking advantage of the teeth to be extracted.

  13. Etiology, Classification and Management of Ectopic Eruption of Permanent First Molars.

    Science.gov (United States)

    Hsiao, Chu-Chun; Boynton, James R

    2016-01-01

    Ectopic eruption of a permanent tooth involves abnormal resorption of a portion or all of the adjacent primary tooth. Among the most commonly ectopically erupted teeth are the permanent first molars. Ectopically erupting molars may require intervention to allow for full eruption, or they may spontaneously self-correct and erupt into occlusion. Decisions regarding the necessity of intervention, its ideal timing, and intervention type are multifactorial. Treatment options for the ectopically erupting permanent first molar include the elastomeric separator, brass wire, pre-fabricated clip separator, custom made appliances (Humphrey appliance, Halterman appliance), or extraction of the primary molar. Early intervention when indicated can ensure proper full eruption of the permanent first molar and prevent mesial angulation, arch perimeter loss, tooth impaction and ankylosis. Two cases are described that manage ectopic eruption of the permanent first molar.

  14. Analysis of dentition of a living wild population of ring-tailed lemurs (Lemur catta) from Beza Mahafaly, Madagascar.

    Science.gov (United States)

    Sauther, M L; Cuozzo, F P; Sussman, R W

    2001-03-01

    Detailed descriptions of the dentition of many strepsirhine primate taxa are rare, despite their importance in understanding primate evolutionary biology. While several researchers have provided detailed morphological descriptions of ring-tailed lemur dentition (e.g., Schwartz and Tattersall [1985] Am. Mus. Nat. Hist. Anthropol. Pap. 60:1-100; Tattersall and Schwartz [1991] Am. Mus. Nat. Hist. Anthropol. Pap. 69:2-18), there are few studies (e.g., Eaglen [1986] Am. J. Phys. Anthropol. 71:185-201) that present quantitative data on the dentition of this species. Furthermore, prior analyses were based on museum specimens from various populations and locations. We present here quantitative and morphological data on the dentition of a population of wild Lemur catta from Beza Mahafaly Special Reserve, Madagascar. Measurements were made on dental casts (n = 39) taken from living members of this L. catta population. Our analysis indicates that no significant (P > 0.05) sexual dimorphism exists for the 30 dental measurements collected. These data support the generalizations (e.g., Plavcan and van Schaik [1994] Evol. Anthropol. 2:208-214; Kappeler [1996] J. Evol. Biol. 9:43-65) that little sexual dimorphism in dentition exists among Malagasy strepsirhines. In addition, the overall patterns of metric variation in this sample compare favorably with patterns seen among other primates, e.g., premolar measurements varying more than molars (e.g., Gingerich [1974] J. Paleontol. 48:895-903). However, there is a degree of intraspecific morphological variation indicated, with one of the morphological traits discussed in other studies as being species-specific for L. catta (absence of P(4) metaconids) observed to vary between specimens. Because the patterns of variation seen in this sample are from a known breeding population, the data presented here provide an important reference for interpreting and understanding the fossil record.

  15. New permanent magnets; manganese compounds.

    Science.gov (United States)

    Coey, J M D

    2014-02-12

    The exponential growth of maximum energy product that prevailed in the 20th century has stalled, leaving a market dominated by two permanent magnet materials, Nd2Fe14B and Ba(Sr)Fe12O19, for which the maximum theoretical energy products differ by an order of magnitude (515 kJ m(-3) and 45 kJ m(-3), respectively). Rather than seeking to improve on optimized Nd-Fe-B, it is suggested that some research efforts should be devoted to developing appropriately priced alternatives with energy products in the range 100-300 kJ m(-3). The prospects for Mn-based hard magnetic materials are discussed, based on known Mn-based compounds with the tetragonal L10 or D022 structure or the hexagonal B81 structure.

  16. CHALLENGES OF PERMANENT TEACHER TRAINING

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    María Manuela Valles-Ornelas

    2015-07-01

    Full Text Available The new challenges for teachers and managers require to assume permanent formation as a tool for responding effectively and efficiently to them, different perspective to strengthen from the initial teacher education programs. The research was done in a primary school in the state of Chihuahua. The method used was research action, the question was: How can we encourage the lifelong learning and training of the staff of this school, with the purpose to assist them in these processes to improve the service that the school provides to students. The school group is the center of the process, the cooperative and collaborative work accompanied by educational leadership and persuasive provide better results, and all accompanied by the professional selfinvitation.

  17. An Assessment of Curve of Spee in Healthy Human Permanent Dentitions: A Cross Sectional Analytical Study in a Group of Young Indian Population

    Science.gov (United States)

    Hallikerimath, Rajendra B; Mandroli, Praveenkumar S

    2017-01-01

    Introduction An awareness of the standard value of the maxillary and the mandibular curves of Spee may aid the clinician in developing occlusion in the sagittal plane and would be useful when providing prosthetic rehabilitation for patients with occlusal derangement. Aim To assess and compare the radius and depth of curve of Spee in maxillary and mandibular arches in men and women, in a group of young Indian population. Materials and Methods The study cohort consisted of 25 men and 25 women between 19 to 24 years. Impression of maxillary and mandibular arches were made with alginate. Casts were poured in die stone. Standardized digital pictures of the right side of maxillary and mandibular dental casts were made with a digital camera and transferred to a computer. Tips of the distal cusps of molars, premolars and canines of the maxilla and mandible were located. The radius and the depth of the curve of Spee were measured from the digital photographs of dental casts, with the help of ‘dimension tool’ in the computer software (Corel DRAW X5). Mann-Whitney test was used to analyze the difference in the curve of Spee between men and women and the difference between maxillary and mandibular arches. Results The mean values were as follows: a) Men: Radii of curve of Spee in the maxillary and mandibular arch were 140.22±65.98 and 109.67±46.80 respectively; depths of curve of Spee in maxillary and mandibular arch were 1.65±0.67 and 1.49±0.74 respectively; b) Women: Radii of curve of Spee in the maxillary and mandibular arch were 120.58±63.91 and 98.31±63.59 respectively; depths of curve of Spee in maxillary and mandibular arch were 1.45±0.54 and 1.40±0.61 respectively. In the mandibular arch, the difference in the radii (p=0.0467) was statistically significant between men and women. In women, the difference in radii (p=0.0467) between maxillary and mandibular arches was statistically significant. Conclusion The radii and depths of curve of Spee were larger in maxillary than mandibular arches in both men and women. Also, the difference in the radii of mandibular arch was statistically significant between men and women.

  18. Meta-analysis and systematic review of factors biasing the observed prevalence of congenitally missing teeth in permanent dentition excluding third molars.

    Science.gov (United States)

    Rakhshan, Vahid

    2013-10-01

    No meta-analyses or systematic reviews have been conducted to evaluate numerous potential biasing factors contributing to the controversial results on congenitally missing teeth (CMT). We aimed to perform a rather comprehensive meta-analysis and systematic review on this subject. A thorough search was performed during September 2012 until April 2013 to find the available literature regarding CMT prevalence. Besides qualitatively discussing the literature, the meta-sample homogeneity, publication bias, and the effects of sample type, sample size, minimum and maximum ages of included subjects, gender imbalances, and scientific credit of the publishing journals on the reported CMT prevalence were statistically analyzed using Q-test, Egger regression, Spearman coefficient, Kruskal-Wallis, Welch t test (α=0.05), and Mann-Whitney U test (α=0.016, α=0.007). A total of 111 reports were collected. Metadata were heterogeneous (P=0.000). There was not a significant publication bias (Egger Regression P=0.073). Prevalence rates differed in different types of populations (Kruskal-Wallis P=0.001). Studies on orthodontic patients might report slightly (about 1%) higher prevalence (P=0.009, corrected α=0.016). Non-orthodontic dental patients showed a significant 2% decline [P=0.007 (Mann-Whitney U)]. Enrolling more males in researches might significantly reduce the observed prevalence (Spearman ρ=-0.407, P=0.001). Studies with higher minimums of subjects' age showed always slightly less CMT prevalence. This reached about -1.6% around the ages 10 to 13 and was significant for ages 10 to 12 (Welch t test P0.2). Studies' sample sizes were correlated negatively with CMT prevalence (ρ=-0.250, P=0.009). It was not verified whether higher CMT rates have better chances of being published (ρ=0.132, P=0.177). CMT definition should be unified. Samples should be sex-balanced. Enrolling both orthodontic and dental patients in similar proportions might be preferable over sampling from each of those groups. Sampling from children over 12 years seems advantageous. Two or more observers should examine larger samples to reduce the false negative error tied with such samples.

  19. Alveolar process fractures in the permanent dentition. Part 2. The risk of healing complications in teeth involved in an alveolar process fracture

    DEFF Research Database (Denmark)

    Lauridsen, Eva; Gerds, Thomas; Andreasen, Jens Ove

    2016-01-01

    for PN (age, fracture in relation to apex, displacement, gingival injury, degree of repositioning, type of splint, duration of splinting, treatment delay, and antibiotics) were analyzed for mature teeth using Cox regression. The level of significance was 5%. RESULTS: Immature: No severe complications (PN.......3-3.5), P = 0.003), and age >30 years (HR: 2.3 (95% CI: 1.1-4.6), P = 0.02). The type of splint (rigid or flexible), the duration of splinting (more or less than 4 weeks), and the administration of antibiotics did not affect the risk of PN. CONCLUSION: Teeth involved in alveolar process fractures appear......AIM: To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorption (RRR), infection-related resorption (IRR), ankylosis-related resorption (ARR), marginal bone loss (MBL), and tooth loss (TL) for teeth involved in an alveolar process fracture and to identify...

  20. Dental Interventions on First Permanent Molars

    OpenAIRE

    2016-01-01

    The first permanent molars have the biggest dental morbidity and mortality of all permanent teeth. The main aim was to evaluate of the most common dental problems and procedures that are performed on the first permanent molars. Material and method: examination was performed in three private dental offices, two from urban and one from rural region, over a period of 2 years. The data was obtained by using dental charts from the patients and by the ambulatory register for performe...

  1. Comparative assessment of dentition status among poliomyelitis children in Udaipur, India.

    Science.gov (United States)

    Nagarajappa, Ramesh; Tak, Mridula; Sharda, Archana J; Asawa, Kailash; Ramesh, Gayathri; Sandesh, Nagarajappa

    2013-01-01

    To determine and compare the dental caries experience and treatment needs of children with Poliomyelitis at Udaipur, India. Total sample comprised of 344 children with Poliomyelitis (upper limb disability: 33.4%; lower limb disability: 33.7%; both upper and lower limb disability: 32.8%) in the age group of 12-15 years. Clinical examination included recording Dentition Status and Treatment Needs. Chi-square test, Analysis of variance (ANOVA), multiple logistic and stepwise linear regressions were used for statistical analysis. The mean decayed, missing, filled teeth (DMFT) score (4.47 ± 3.09) was found to be highest among children with Poliomyelitis having both upper and lower limb impairment (p < .05). Stepwise and logistic regression analysis showed that the best predictors for dental caries were disability, socioeconomic status and snacks in between meals. A significant relationship of dental caries with limb involved in impairment draws immediate attention for a planned approach in improving the oral health.

  2. The effects of infant feeding patterns on the occlusion of the primary dentition.

    Science.gov (United States)

    Charchut, Steven W; Allred, Elizabeth N; Needleman, Howard L

    2003-01-01

    The purpose of this study was to investigate the effects of different methods of infant feeding on the development of the occlusion in the primary dentition. The study included 126 children. Parents completed questionnaires regarding feeding and health history, and the primary dental occlusion was recorded for each child. The authors found that: (1) predominant bottle-feeding between 0 and 6 months of age was associated with the development of a pacifier habit; (2) children who used a pacifier were more likely to develop a nonmesial step occlusion, an overjet >3 mm, and an open bite; (3) children who sucked their thumb were more likely to develop an overjet >3 mm; and (4) in the absence ofnonnutritive oral habits, children who were predominantly bottle-fed between 0 and 6 months of age were more likely to develop an overbite >75%, although just shy of nominal statistical significance.

  3. Permanence of Stochastic Lotka-Volterra Systems

    Science.gov (United States)

    Liu, Meng; Fan, Meng

    2017-04-01

    This paper proposes a new definition of permanence for stochastic population models, which overcomes some limitations and deficiency of the existing ones. Then, we explore the permanence of two-dimensional stochastic Lotka-Volterra systems in a general setting, which models several different interactions between two species such as cooperation, competition, and predation. Sharp sufficient criteria are established with the help of the Lyapunov direct method and some new techniques. This study reveals that the stochastic noises play an essential role in the permanence and characterize the systems being permanent or not.

  4. Dental caries in the primary dentition of german children with cleft lip, alveolus, and palate.

    Science.gov (United States)

    Kirchberg, Anja; Makuch, Almut; Hemprich, Alexander; Hirsch, Christian

    2014-05-01

    Objective : The purpose of this cross-sectional study was to assess the prevalence of dental caries in children with cleft lip, alveolus, and/or cleft palate living in central Germany between 1996 and 2010. Participants : A total of 295 children 1 to 6 years of age from three birth cohorts (BC) with clefts from central Germany were included in the study. They were compared with 548 1- to 6-year-old cleft-free children from the same region. Setting : Children with clefts underwent a dental examination in an outpatient dental clinic at the University of Leipzig. The first BC was examined between 1996 and 1998, the second between 2002 and 2004, and the third between 2008 and 2010. Controls were examined at day-care centers in Leipzig during the same periods. Main Outcome Measure : The standard dental caries index for the primary dentition (dmf/t3-4) was used for clinical assessment. Results : Over the entire study period, the mean prevalence of dental caries in deciduous teeth was significantly higher (1.32 dmf/t3-4) in children with clefts compared with cleft-free children. However, a decline in caries (approximately 1 dmf/t3-4) and an increase in the proportion of children with healthy primary dentition were observed in both groups. These results represent a caries decline of 61% in children with clefts. Conclusions : Caries rates for children 1 to 6 years of age with clefts from central Germany showed a considerable decline over the last years. The caries rates for clefts patients in the third BC (2008 to 2010) was similar to that of cleft-free children in the first BC (1996 to 1998).

  5. Incisor and molar overjet, arch contraction, and molar relationship in the mixed dentition in repaired complete unilateral cleft lip and palate: A qualitative and quantitative appraisal.

    Science.gov (United States)

    Disthaporn, Suteeta; Suri, Sunjay; Ross, Bruce; Tompson, Bryan; Baena, Diogenes; Fisher, David; Lou, Wendy

    2017-07-01

    To compare the mixed dentition incisor and molar overjet, severity of contraction of the dental arch, and the sagittal molar relationship on the cleft side vs the noncleft side in children with repaired complete unilateral cleft of the lip and palate (UCLP). Orthodontic records taken prior to orthodontic preparation for alveolar bone grafting were screened to select study casts from patients with nonsyndromic repaired complete UCLP who did not have mandibular skeletal or dental asymmetry. The study sample comprised dental casts from 74 children aged 8.9 ± 1 years. Standardized digital photographs were acquired at 1:1 magnification. A coordinate system was developed using digital image-processing software (Photoshop CS4 and Adobe Illustrator). Incisor and molar overjet, Angle's classification, and arch contraction were recorded. Descriptive statistics, paired t-tests, and kappa statistics were used to compare the cleft and noncleft sides. A negative overjet of -1 to -5 mm was often present at the incisors, with greater frequency and magnitude on the cleft side. Class II molar relation was more frequent on the cleft side (61.1%) than on the noncleft side (47.2%). Significantly greater contraction of the cleft side deciduous canine and deciduous first molar was noted, while the difference was very minor at the first permanent molar. Cleft side maxillary arch contraction was most severe in the deciduous canine and first deciduous molar region and progressively less severe in the posterior region of the arch. A greater frequency and severity of negative overjet and Class II molar relationship was seen on the cleft side.

  6. Iranian Permanent GPS Network for Geodynamics (IPGN)

    Science.gov (United States)

    Tavakoli, F.; Nankali, H. R.; Sedighi, M.; Djamour, Y.; Mosavi, Z.

    2009-04-01

    Iran is one of the most tectonically active zone in Alpine-Himalayan seismic belt where has been shaken by largely destroying historical and instrumental earthquakes. Iran is located in the convergence zone between Arabia and Eurasia with a velocity of 22 mm/yr nearly to the North. The shortening between Arabian and Eurasian plates in Iran is mainly distributed on Zagros and Alborz belts. Despite the historical and scientific awareness of seismic hazard in Iran, unfortunately this country lacked a Continuous GPS network to study geodynamic and tectonic movements. Such geodetic measurement can play an important role to understand the tectonic deformation then to evaluate the seismic hazard on Iran. Since early 2005 National Cartographic Center of Iran (NCC) is establishing a continuous GPS network named Iranian Permanent GPS Network for Geodynamics (IPGN). Taking into account the number of provided GPS receivers, (108) we made a priority based on two factors of seismicity and population. At the first, in order to study general tectonic behavior in Iran 41 stations, globally distributed in whole of Iran, were been considered. Three other areas in the priority list were: Centeral Alborz, North-West of Iran and North-East of Iran. The rest of receivers, i.e. ~60, were considered for these areas as local networks. These four networks are daily processed and give us a continuous monitoring of any surface deformation. In this paper we try to present the results obtained from the network

  7. 22 CFR 401.3 - Permanent offices.

    Science.gov (United States)

    2010-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  8. resonant inverter supplied interior permanent magnet (ipm)

    African Journals Online (AJOL)

    user

    Permanent Magnet (IPM) or Surface Permanent. Magnet ... desired torque is produced to rotate the motor in the desired ... u axis, and the direct-axis of the rotor is at angle θ from the ..... Based Stator Flux Estimator” International. Journal of ...

  9. Comparison of adjustable permanent magnetic field sources

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Bahl, Christian Robert Haffenden; Smith, Anders

    2010-01-01

    A permanent magnet assembly in which the flux density can be altered by a mechanical operation is often significantly smaller than comparable electromagnets and also requires no electrical power to operate. In this paper five permanent magnet designs in which the magnetic flux density can...

  10. Magnetic guns with cylindrical permanent magnets

    DEFF Research Database (Denmark)

    Vokoun, David; Beleggia, Marco; Heller, Luděk

    2012-01-01

    The motion of a cylindrical permanent magnet (projectile) inside a tubular permanent magnet, with both magnets magnetized axially, illustrates nicely the physical principles behind the operation of magnetic guns. The force acting upon the projectile is expressed semi-analytically as derivative...

  11. Clinical retrospective analysis of children for mixed dentition traumatic anterior teeth completely dislocation replantation%替牙期外伤性前牙完全脱位再植术的临床分析

    Institute of Scientific and Technical Information of China (English)

    赵然; 李凤和; 陈光

    2012-01-01

    目的:探讨替牙期完全脱位前牙再植术后的效果和相关影响因素.方法:对48例患儿58颗完全脱位前牙治疗方法和临床疗效进行分析.脱位前牙再植后复诊行牙髓测试、牙周检查,2周牙髓活力阴性的患牙行根尖诱导成形术,6个月~3年根尖孔完全形成后行根管永久充填治疗.结果:再植术后3年,5颗患牙活力存在,牙髓存活率达8.62%; 53颗患牙行根管治疗术后行X线检查,25颗患牙牙根牙周膜愈合,30颗患牙牙根部分牙周膜愈合和部分骨性愈合,3颗患牙不同程度牙根内外吸收,但无1例脱落.结论:早就诊且合理处理脱落牙、牙髓血管再生是牙再植术成功的关键,根尖诱导成形术可使替牙期牙根再度形成,牙骨质沉积于根端、封闭根尖孔,是替牙期脱位前牙治疗的重要手段,根管治疗可预防或减少脱位牙牙根的吸收.%Objective To explore the effects and related influential factors of replantation after complete dislocation of anterior teeth/tooth on mixed dentition patients experiencing tooth transitions. Methods Analysis of 48 patients with 58 traumatic anterior teeth were made based on treatments recieved and clinical observations.After the reimplantation for the traumatic anterior teeth, patients returned for dental pulp test and periodontal examination. 2 weeks later, apexification was performed after the dental pulp test had indicated a negative result.Six months to 3 years after apexification, permanent canal filling treatment was made once the apical had been fully formed. Results three years after the replantation,5 teeth exist vitality with a dental pulp survival rate of 8.62%; X-ray examination indicates that out of the 53 teeth have had apexification and canal filling treatment:25 teeth's tooth roots have periodontal ligament fully recovered (bined together or have been healed),30 teeth's teeth root have fully recovered iodontal ligaments and partial recover of the bone

  12. Leadership in a (permanent) crisis.

    Science.gov (United States)

    Heifetz, Ronald; Grashow, Alexander; Linsky, Marty

    2009-01-01

    The current economic crisis is not just another rough spell. Today's mix of urgency, high stakes, and uncertainty will continue even after the recession ends. The immediate crisis--which we will get through with policy makers' expert technical adjustments--sets the stage for a sustained, or even permanent, crisis, a relentless series of challenges no one has encountered before. Instead of hunkering down and relying on their familiar expertise to deal with the sustained crisis, people in positions of authority--whether they are CEOs or managers heading up a company initiative--must practice what the authors call adaptive leadership. They must, of course, tackle the underlying causes of the crisis, but they must also simultaneously make the changes that will allow their organizations to thrive in turbulent environments. Adaptive leadership is an improvisational and experimental art, requiring some new practices. Like Julie Gilbert, who overcame internal resistance to reorient Best Buy toward female purchasers, adaptive leaders get things done to meet today's challenges and then modify those things to thrive in tomorrow's world. They also embrace disequilibrium, using turbulence as an opportunity to build crucial new capacities, as Paul Levy did to rescue Beth Israel Deaconess Medical Center from a profound financial crisis. Finally, adaptive leaders, such as Egon Zehnder, the founder of an executive search firm, draw out the leadership skills that reside deep in the organization, recognizing the interdependence of all employees and mobilizing everyone to generate solutions.

  13. Finite element modeling of permanent magnet devices

    Science.gov (United States)

    Brauer, J. R.; Larkin, L. A.; Overbye, V. D.

    1984-03-01

    New techniques are presented for finite element modeling of permanent magnets in magnetic devices such as motors and generators. These techniques extend a previous sheet-current permanent magnet model that applies only for straight line B-H loops and rectangular-shaped magnets. Here Maxwell's equations are used to derive the model of a permanent magnet having a general curved B-H loop and any geometric shape. The model enables a nonlinear magnetic finite element program to use Newton-Raphson iteration to solve for saturable magnetic fields in a wide variety of devices containing permanent magnets and steels. The techniques are applied to a brushless dc motor with irregular-shaped permanent magnets. The calculated motor torque agrees well with measured torque.

  14. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  15. Using zirconia-based prosthesis in a complete-mouth reconstruction treatment for worn dentition with the altered vertical dimension of occlusion.

    Science.gov (United States)

    Nam, Jung; Tokutomi, Hiro

    2015-02-01

    This clinical report describes the complete mouth reconstruction of a patient with a worn dentition. Computer-aided design and computer-aided manufacturing processed porcelain fused-to-zirconia prostheses were used to achieve good esthetics, function, and biomechanics.

  16. Perda precoce de molares permanentes e fatores associados em escolares de 9, 12 e 15 anos da rede pública municipal de Campina Grande, Estado da Paraíba, Brasil = Early loss of permanent molars and associated factors in schoolchildren aged 9, 12 and 15 years attending public schools in Campina Grande, Paraíba State, Brazil

    Directory of Open Access Journals (Sweden)

    Francineide Guimarães Carneiro de Melo

    2011-01-01

    Full Text Available Este estudo avaliou a perda precoce de molares permanentes em escolares da rede pública de Campina Grande, Estado da Paraíba, com idades de nove, 12 e 15 anos. A amostra compreendeu 873 escolares, aleatoriamente selecionados. O instrumento de coleta consistiu de um questionário e de uma ficha clínica. As variáveis do estudo compreenderam os aspectos relativos à perda dentária (tipo de elemento dental, localização na arcada dentária e a região do arco, à prevenção e à autopercepção em saúde bucal. A análise estatística compreendeu a distribuição de frequências e os testes do Qui-quadrado e Exato de Fisher. Os resultados revelaram a prevalência de 17,2% de perda dentária, sem diferenças entre os sexos, frequência de escovação e palestra educativa (p > 0,05. Os elementos dentários 36 (42,5% e 46 (33,9% foram os mais frequentemente perdidos. Observou-se a associação positiva entre perda dentária e as variáveis idade, visita ao cirurgião-dentista (OR = 2,19; IC95%: 1,35-3,59, satisfação com o sorriso (OR = 0,40; IC95%: 0,24-0,65 e a dificuldade na mastigação (OR = 2,16; IC95%: 1,48- 3,16. Conclui-se que a prevalência da perda precoce de molares permanentes foi elevada, sendo necessária a imediata adoção de ações curativas a fim de reduzir a perda precoce desses elementos dentários.This study evaluate the early loss of permanent molars in schoolchildren aged 9, 12 and 15 years attending public schools in the city of Campina Grande, Paraíba State, Brazil. The sample was composed of 873 randomly selected schoolchildren. The instrument for data collection was a questionnaire and a clinical chart. The following variables were analyzed: tooth loss (tooth type, localization in the dental arch and region of the arch, prevention and selfperception of oral health. The statistical analysis was done by frequency distribution and the chisquare and fisher’s exact tests were used. The results showed a prevalence of

  17. A Comparative Evaluation of Mixed Dentition Analysis on Reliability of Cone Beam Computed Tomography Image Compared to Plaster Model.

    Science.gov (United States)

    Gowd, Snigdha; Shankar, T; Dash, Samarendra; Sahoo, Nivedita; Chatterjee, Suravi; Mohanty, Pritam

    2017-01-01

    The aim of the study was to evaluate the reliability of cone beam computed tomography (CBCT) obtained image over plaster model for the assessment of mixed dentition analysis. Thirty CBCT-derived images and thirty plaster models were derived from the dental archives, and Moyer's and Tanaka-Johnston analyses were performed. The data obtained were interpreted and analyzed statistically using SPSS 10.0/PC (SPSS Inc., Chicago, IL, USA). Descriptive and analytical analysis along with Student's t-test was performed to qualitatively evaluate the data and P plaster model; the mean for Moyer's analysis in the left and right lower arch for CBCT and plaster model was 21.2 mm, 21.1 mm and 22.5 mm, 22.5 mm, respectively. CBCT-derived images were less reliable as compared to data obtained directly from plaster model for mixed dentition analysis.

  18. Masticatory performance and food acceptability in persons with removable partial dentures, full dentures and intact natural dentition.

    Science.gov (United States)

    Wayler, A H; Muench, M E; Kapur, K K; Chauncey, H H

    1984-05-01

    This investigation indicated that measurable declines in masticatory function due to missing teeth, with and without prosthetic replacements, alter perceptual estimates of food acceptability. Using 1,133 male participants from the Veterans Administration Dental Longitudinal Study, individuals were classified into nine dentition categories to evaluate the effect of impaired masticatory ability. The data demonstrated that when limited declines in perceived masticatory function occur, perceptual estimates of Taste Acceptability, Texture Acceptability, and Ingestion Frequency for the 13 test foods utilized are not significantly modified. In contrast, when more severe dentition losses occur, the rheological properties of each food determine the degree to which these perceptual measures, especially Perceived Ease of Chewing, will be altered. Although restorative therapy can lead to concomitant improvements in masticatory function, low perceptual responses may still be observed. These appear to be largely a function of the physical attributes of the foods ingested.

  19. Auditory Screening in Infants for Early Detection of Permanent ...

    African Journals Online (AJOL)

    Annals of Medical and Health Sciences Research | May-Jun 2014 | Vol 4 | Issue 3 |. Address ... Introduction ... Background: Undiagnosed hearing loss can cause disorders in speech and .... to noise generates acoustic energy, known as OAE's.

  20. Formation and dynamics features of maxillary dentition development in patients with right-sided transverse congenital clefts of the upper lip and palate after surgical interferences

    Directory of Open Access Journals (Sweden)

    Адріан Юрійович Олійник

    2015-06-01

    Full Text Available Aim. The research is to analyze studying dynamics of formation and features of maxillary dentition deformities in patients’ age aspect with right-sided transverse congenital clefts of the upper lip and palate after surgical interferences.Methods. The analysis of 24 diagnostic patient models with right-sided transverse congenital clefts of the upper lip and palate has been done according to the age and sex peculiarities. The maxillary dentition width compared to the normal state and the length of the upper jaw’s frontal area.Results. The following features of the maxillary dentition state have been detected: the maxillary dentition’s asymmetric narrowing due to larger displacement of small fragment of cleft upper jaw inward; the upper jaw’s lagging in growth in the sagittal direction, which increases with age; asymmetric placement of similar teeth in dentition; in a later age configuration of the maxillary dentition gets even more distorted because of the vestibular cuspid dentition.Conclusions. Detected features of formation of deformations of the upper jaw dental row and their dynamics in patients with right-sided transverse congenital cleft of upper lip and palate should be considered in providing orthodontic care to these patients and choosing the right construction for their further orthopedic treatment

  1. Padrão facial na dentadura decídua: estudo epidemiológico Facial pattern in the deciduous dentition: epidemiologic study

    Directory of Open Access Journals (Sweden)

    Omar Gabriel da Silva Filho

    2008-08-01

    Full Text Available INTRODUÇÃO: é possível definir a morfologia facial e o padrão de crescimento em idade precoce, a partir da dentadura decídua completa. OBJETIVOS: frente à escassez de trabalhos na literatura pertinente ao assunto, a presente pesquisa explora o diagnóstico epidemiológico da face no estágio de dentadura decídua. METODOLOGIA: a amostra foi composta por 2.009 crianças de etnia brasileira, de ambos os gêneros, entre 3 e 6 anos de idade, no período de dentadura decídua completa, de 20 pré-escolas do município de Bauru/SP. RESULTADOS E CONCLUSÕES: baseando-se nos resultados obtidos no levantamento epidemiológico, foi encontrado - na análise em norma lateral - predomínio de crianças Padrão I (63,22% em relação ao Padrão II (33,10% e Padrão III (3,68%, não havendo diferenças estatisticamente significativas quanto ao gênero. Na análise em norma frontal, houve predomínio do tipo mesofacial (64,56% em relação ao dolicofacial (21,90% e braquifacial (13,54%, sendo que a proporção do tipo braquifacial nas meninas foi significativamente superior em relação aos meninos. Na distribuição dos tipos faciais frontais dentro dos padrões faciais sagitais ficou evidenciada uma manifestação mais freqüente do tipo dolicofacial dentro dos Padrões II e III, sendo encontrado dimorfismo quanto ao gênero, notadamente no Padrão I, onde houve maior manifestação do tipo braquifacial e menor manifestação do dolicofacial no gênero feminino.INTRODUCTION: It is possible to define the facial morphology and growth pattern in early ages, starting from mature deciduous dentition. AIM: Due to the lack of studies about this issue in the deciduous dentition, the current paper aims to present the epidemiologic diagnosis of the face in this stage of the occlusal development. METHODS: The sample was comprised of 2,009 Brazilian children aged between 3 and 6 years, all in the deciduous dentition, from 20 schools in Bauru/SP. RESULTS AND

  2. Permanency and the Foster Care System.

    Science.gov (United States)

    Lockwood, Katie K; Friedman, Susan; Christian, Cindy W

    2015-10-01

    Each year over 20,000 youth age out of the child welfare system without reaching a permanent placement in a family. Certain children, such as those spending extended time in foster care, with a diagnosed disability, or adolescents, are at the highest risk for aging out. As young adults, this population is at and increased risk of incarceration; food, housing, and income insecurity; unemployment; educational deficits; receipt of public assistance; and mental health disorders. We reviewed the literature on foster care legislation, permanency, outcomes, and interventions. The outcomes of children who age out of the child welfare system are poor. Interventions to increase permanency include training programs for youth and foster parents, age extension for foster care and insurance coverage, an adoption tax credit, and specialized services and programs that support youth preparing for their transition to adulthood. Future ideas include expanding mentoring, educational support, mental health services, and post-permanency services to foster stability in foster care placements and encourage permanency planning. Children in the child welfare system are at a high risk for physical, mental, and emotional health problems that can lead to placement instability and create barriers to achieving permanency. Failure to reach the permanency of a family leads to poor outcomes, which have negative effects on the individual and society. Supporting youth in foster care throughout transitions may mediate the negative outcomes that have historically followed placement in out-of-home care. Copyright © 2015 Mosby, Inc. All rights reserved.

  3. Prevalence of mesiodens in orthodontic patients with deciduous and mixed dentition and its association with other dental anomalies

    OpenAIRE

    Tulio Silva Lara; Melissa Lancia; Omar Gabriel da Silva Filho; Daniela Gamba Garib; Terumi Okada Ozawa

    2013-01-01

    OBJECTIVE: To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. MATERIAL AND METHODS: Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender ; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment pl...

  4. Evaluation of sexual dimorphism and the relationship between craniofacial, dental arch and masseter muscle characteristics in mixed dentition

    OpenAIRE

    Marquezin, Maria Carolina Salomé; Andrade, Annicele da Silva; Rossi, Moara de; Gameiro, Gustavo Hauber; Gavião, Maria Beatriz Duarte; Castelo,Paula Midori

    2014-01-01

    Purpose: to evaluate sexual dimorphism and the relationship between craniofacial characteristics, dental arch morphology and masseter muscle thickness in children in the mixed dentition stage. Methods: the study sample comprised 32 children, aged 6-10 years (14♀/18♂) with normal occlusion. Craniofacial characteristics, dental morphology and masseter muscle thickness were evaluated by means of posteroanterior cephalometric radiographs, dental cast evaluation and ultrasound exam, respectively. ...

  5. Effect of serial extraction alone on crowding: relationship between closure of residual extraction space and changes in dentition.

    Science.gov (United States)

    Yoshihara, Toshihiro; Matsumoto, Yuko; Suzuki, Junichi; Ogura, Tadashi

    2002-01-01

    Mandibular dentitions from 33 subjects who had undergone serial extraction without appliances were analyzed at three stages: before extraction of deciduous canines (T1), after extraction of first premolars (T2), and at the end of the observation (T3). It was suggest that the mesial movement or tipping of the second premolars was associated with most of the space closure from T2 to T3, although the distal movement or tipping of canines might also contribute space closure.

  6. Prevention of dental anomalies in children by prosthetics defects hard tooth tissues and dentitions: the need to possibilities

    OpenAIRE

    Suetenkov D.Ye.; Pudovkina Е.А.; Venatovskaya N.V.; Proshin A.G.

    2011-01-01

    This article presents the possibility of restore the function and anatomy of the tooth and replacement of defects of dentition by prosthesis in children under the removable bite as a method of prevention of dentoalveolar anomalies. Identified the need for prosthetic treatment of children and the willingness of dentists as primary health care professional to address the problems identified. A clinical analysis of complex treatment of defects in the teeth with fixed restorations

  7. Prevention of dental anomalies in children by prosthetics defects hard tooth tissues and dentitions: the need to possibilities

    Directory of Open Access Journals (Sweden)

    Suetenkov D.Ye.

    2011-03-01

    Full Text Available This article presents the possibility of restore the function and anatomy of the tooth and replacement of defects of dentition by prosthesis in children under the removable bite as a method of prevention of dentoalveolar anomalies. Identified the need for prosthetic treatment of children and the willingness of dentists as primary health care professional to address the problems identified. A clinical analysis of complex treatment of defects in the teeth with fixed restorations

  8. Exploring the association between feeding habits, non-nutritive sucking habits, and malocclusions in the deciduous dentition

    OpenAIRE

    Lopes-Freire, Gabriela Mesquita; Cárdenas, Abel Belizario Cahuana; Suarez de Deza, José Enrique Espasa; Ustrell-Torrent, Josep Maria; Oliveira,Luciana Butini; Boj Quesada JR, Joan Ramon

    2015-01-01

    Background This study aimed to explore the association between feeding habits, non-nutritive sucking habits, and malocclusions in deciduous dentition. Methods A cross-sectional observational survey was carried out in 275 children aged 3 to 6 years and included clinical evaluations of malocclusions and structured interviews. Statistical significance for the association between feeding habits and the development of malocclusion was determined using chi-square and Fisher’s exact tests. In additi...

  9. Evolution of the hypercarnivorous dentition in mammals (Metatheria, Eutheria) and its bearing on the development of tribosphenic molars.

    Science.gov (United States)

    Solé, Floréal; Ladevèze, Sandrine

    2017-03-01

    One major innovation of mammals is the tribosphenic molar, characterized by the evolution of a neomorphic upper cusp (=protocone) and a lower basin (=talonid) that occlude and provide shearing and crushing functions. This type of molar is an evolutionarily flexible structure that enabled mammals to achieve complex dental adaptations. Among carnivorous mammals, hypercarnivory is a common trend that evolved several times among therians (marsupials, placentals, and stem relatives). Hypercarnivory involves an important simplification of the carnassial molar pattern from the ancestral tribosphenic molar pattern, with the modification of the triangular tooth crown, and the loss of several cusps and cuspids typical of the tribosphenic molar. These losses confer to the molars of the hypercarnivorous mammals a plesiomorphic/paedomorphic morphology that resembles more the earliest mammaliaforms than the earliest therians. Here, we demonstrate that the modification of the molar morphology is fully explained by a patterning cascade mode of cusp development. Contrary to what was previously proposed, our study concludes that the metaconid (mesiolingual cusp of lower molars, associated with a puncturing function) does not influence cusp development of the talonid (distal crushing heel of lower molars). Moreover, it provides a new example of how heterochronic changes were crucial to the evolution of mammal dentition. To overcome the difficulty of applying behavioral or ecological definitions of diets to fossil animals, we characterize hypercarnivorous dentitions on the basis of the molar morphology and more particularly on the loss or retention of crushing structures, each dentition resulting from adaptations to a distinct ecomorphotype. Despite repeated and convergent evolution of hypercarnivorous forms, hypercarnivory appears as a highly constrained specialization (i.e., "dead end") that is unlikely to evolve back to omnivorous dentition, especially when the crushing structures

  10. Tooth wear in the deciduous dentition of 5-7-year-old children: risk factors.

    Science.gov (United States)

    Gatou, Tarsitsa; Mamai-Homata, Eleni

    2012-06-01

    This study was conducted to investigate the distribution and severity of tooth wear in deciduous dentition and its relationship with possible risk factors. A stratified cluster sample of 243 5-7-year-old children was examined using the tooth wear index of Smith and Knight, and their exposure to intrinsic and extrinsic risk factors was retrospectively investigated through a structured questionnaire. The severity of wear was quantitatively estimated by the number of surfaces with affected dentine and by the cumulative score of the sextants, based on the Basic Erosive Wear Examination scoring system. Only 1.6% of the children were tooth wear free, whereas 45.6% had moderate to severe wear involving dentine. Maxillary canines were the most affected teeth (83.2%), and occlusal/incisal the most affected surfaces (52.7%). The likelihood of tooth wear involving dentine was greater in boys than girls (OR = 1.72), in immigrants than in Greeks (OR = 1.93), and in 6- and 7-year olds than in 5-year olds (OR = 2.78 to 2.93). After adjustment for age, gender, and nationality, exposure to several dietary factors and especially to soft drinks was found to significantly affect the prevalence (OR = 1.27) and the severity of tooth wear. Every additional serving/week of consumption of soft drinks increases the number of surfaces with dentine affected by 0.03 per year (p children with the higher prevalence and severity of tooth wear had an average exposure to soft drinks of 10 servings/week for a duration of 4 years. The cumulative score of sextants was better predicted by the assessed risk factors, in comparison with the number of surfaces with affected dentine. Tooth wear is a common condition in children, related both to the physiological process of aging of dentition and to the erosive effect of dietary factors. Strategies to reduce the intake of soft drinks in children are expected to have multiple benefits preventing tooth wear in childhood and in later life, as well as many other

  11. Dental crowding in primary dentition and its relationship to arch and crown dimensions among preschool children of Davangere.

    Science.gov (United States)

    Prabhakar, A R; Ravi, G R; Kurthukoti, Ameet J; Shubha, A B

    2008-01-01

    The purpose of the present study was to evaluate dental crowding in the deciduous dentition and its relationship to the crown and the arch dimensions among preschool children of Davangere. Stratified randomized selection of one hundred, 3-4 year old healthy children with all primary teeth erupted was done and divided into two groups. One group had children with anterior crowding in both the arches while the other had spacing. Alginate impressions of the upper and lower arches were made and the study casts were obtained. The tooth and arch dimensions were determined. Mesiodistal dimensions of all the teeth were significantly larger in the crowded arch group. However, the buccolingual dimensions of the maxillary right central incisor, mandibular lateral incisors and the maxillary molars and the crown shape ratio of maxillary lateral incisors, mandibular canines and mandibular right second molar was statistically different. No significant correlation was found between the arch width and the presence of crowding of deciduous dentition. The arch depth of the spaced dentition was greater when compared to the crowded ones. The arch perimeter of the crowded arches was significantly less than the spaced arches.

  12. Reiterative pattern of sonic hedgehog expression in the catshark dentition reveals a phylogenetic template for jawed vertebrates.

    Science.gov (United States)

    Smith, Moya M; Fraser, Gareth J; Chaplin, Natalie; Hobbs, Carl; Graham, Anthony

    2009-04-01

    For a dentition representing the most basal extant gnathostomes, that of the shark can provide us with key insights into the evolution of vertebrate dentitions. To detail the pattern of odontogenesis, we have profiled the expression of sonic hedgehog, a key regulator of tooth induction. We find in the catshark (Scyliorhinus canicula) that intense shh expression first occurs in a bilaterally symmetrical pattern restricted to broad regions in each half of the dentition in the embryo jaw. As in the mouse, there follows a changing temporal pattern of shh spatial restriction corresponding to epithelial bands of left and right dental fields, but also a subfield for symphyseal teeth. Then, intense shh expression is restricted to loci coincident with a temporal series of teeth in iterative jaw positions. The developmental expression of shh reveals previously undetected timing within epithelial stages of tooth formation. Each locus at alternate, even then odd, jaw positions establishes precise sequential timing for successive replacement within each tooth family. Shh appears first in the central cusp, iteratively along the jaw, then reiteratively within each tooth for secondary cusps. This progressive, sequential restriction of shh is shared by toothed gnathostomes and conserved through 500 million years of evolution.

  13. Permanent Magnetic Bearing for Spacecraft Applications

    Science.gov (United States)

    Morales, Winfredo; Fusaro, Robert; Kascak, Albert

    2008-01-01

    A permanent, totally passive magnetic bearing rig was designed, constructed, and tested. The suspension of the rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm using an air impeller. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

  14. Macroscopic Simulation of Isotropic Permanent Magnets

    CERN Document Server

    Bruckner, Florian; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2015-01-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the hysteresis of the magnetic material. Strayfield measurements of an isotropic permanent magnet and simulation results are in good agreement and highlight the importance of a proper description of the isotropic material.

  15. Macroscopic simulation of isotropic permanent magnets

    Science.gov (United States)

    Bruckner, Florian; Abert, Claas; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2016-03-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the hysteresis of the magnetic material. Strayfield measurements of an isotropic permanent magnet and simulation results are in good agreement and highlight the importance of a proper description of the isotropic material.

  16. Permanent GNSS Observations at Agh-Ust Satellite Observatory

    Science.gov (United States)

    Kudrys, Jacek

    2016-06-01

    GPS satellite observations at the Faculty of Mining Surveying and Environmental Engineering AGH-UST are conducted since the early 90s of the last century. In 2001, efforts have been made on getting permanently functioning GPS station. At present, observatory is EPN operational center for two GNSS stations KRAW and KRA1. Moreover, KRA1 station is one of fundamental control points in polish horizontal network. The article gives the history and scope of the research carried out in the satellite observatory AGH-UST during the period 2001 - 2015.

  17. From Permanent Neutrality to Relying on the United States--Japanese Government's National Security Conception in the Early Postwar Period%从永久中立到依附美国--简析战后初期日本政府的国家安全构想

    Institute of Scientific and Technical Information of China (English)

    刘树良

    2014-01-01

    In the early period of postwar, Japanese government worked hard to explore a way of how to defend Japan's national security from its demilitarization. Generally speaking, Japan's national security conception experienced an evolution process from permanent neutrality to relying on the United Nations, and ifnally to counting on the United States. Under the international environment of the conlfict between the United States and the Soviet Union, and facing the fact of occupancy by the United States, the policymakers of Japanese government made a strategic decision to depend on the United States by its “follow”mentality. Now the Japanese national security policy, which cultivated the conception of depending on the United States, is in an important transition period. It is noteworthy that how the Abe cabinet will execute its national security policy.%战后初期的日本政府从非武装化的现状出发,积极需求维护国家安全之路。概而言之,其国家安全构想经历了一个从永久中立国到依靠联合国,再到依附美国的演变过程。日本政府决策层最终选择依附美国,是在美苏对立的国际环境下,在被美国占领这一最大现实中,以“追随强者”的结盟心态做出的重大战略决择。在依附美国构想的基础上形成的战后日本国家安全政策目前正处于重要转型期,安倍内阁的国家安全政策走向特别值得关注。

  18. Early diagnostic evaluation of mandibular symmetry using orthopantomogram

    Directory of Open Access Journals (Sweden)

    Francesca Silvestrini-Biavati

    2014-01-01

    Full Text Available Aims: The aim of this research was to complete Habets′s method on orthopantomogram, in order to measure mandibular symmetry horizontally and diagonally in mixed dentition as the first diagnostic evaluation. Settings and Design: Mixed dentition subjects were consecutively selected according to skeletal maturity. Materials and Methods: Inclusion criteria were: Mixed dentition, cervical vertebral stages 1-2, Class II or Class III malocclusions, with or without unilateral posterior cross-bite. Fourteen subjects with cross-bite (mean age 8 y, 9 m cross group (CG and 14 subjects with normal transverse occlusion (mean age 8y, 6m non-cross group (NCG were selected. Nine measurements were determined. An asymmetry index was performed for all linear variables. Statistical Analysis Used: NCG patients′ data were compared with CG data using parametric t-tests. Probabilities of <0.05 were accepted as significant. Results: In CG, comparing right and left side, single values showed no significant differences up to 6% (twice if compared to the 3% threshold value. T-tests showed statistically significant differences between the groups for ramus + condyle height (index 2.5% vs 4.5%, P = 0.04, condylar height (index 3.7% vs 6.6%, P = 0.02 and mandibular length (index 1.4% vs 2.3%, P = 0.04. Overall CG group was more asymmetrical than NCG. Conclusions: In mixed dentition (CS1-2, a first appraisal of mandibular symmetry may be performed on orthopantomogram utilizing this modified Habets′s method. This tracing method provides an early evaluation about mandibular symmetry and is able to show slight asymmetries in mixed dentition thereby reducing the number of cone beam computed tomograms performed.

  19. Evaluation of the Occlusion and Arch Dimensions in the Primary Dentition of an Iranian Population

    Directory of Open Access Journals (Sweden)

    Maryam Talebi

    2013-12-01

    Full Text Available Introduction: The objective of this study was to gather information about normal occlusion and arch dimensions in the primary teeth of the children belonging to an Iranian population. Methods: This descriptive cross-sectional study was performed on 68 children from the city of Mashhad in the 3-5 age range. Dental arch dimensions, interrelationships of primary canine and second molars, overbite and overjet were evaluated. Results: Primate space was observed on both sides of the arch in 82.2% of the subjects. The most prevalent type of primary molar relationship was flush terminal plane (52.1% followed by distal step (31.3% and then mesial step (16.7%. The primary canine relationship was ranked in the descending order of prevalence as Class I (77.1%, Class II (13.5%, end-to-end (5.2% and Class III (4.2%. Normal overbite and normal overjet was observed in 50% and 81.3% of cases, respectively. Conclusion: This study provides an insight into the dental arch dimensions, occlusion, spacing and crowding in primary dentition in Iranian children. In most of the cases, primate space and flush terminal plane were observed.

  20. Evaluation of the Occlusion and Arch Dimensions in the Primary Dentition of an Iranian Population

    Directory of Open Access Journals (Sweden)

    Maryam Talebi

    2013-01-01

    Full Text Available Introduction: The objective of this study was to gather information about normal occlusion and arch dimensions in the primary teeth of the children belonging to an Iranian population. Methods: This descriptive cross-sectional study was performed on 68 children from the city of Mashhad in the 3-5 age range. Dental arch dimensions, interrelationships of primary canine and second molars, overbite and overjet were evaluated. Results: Primate space was observed on both sides of the arch in 82.2% of the subjects. The most prevalent type of primary molar relationship was flush terminal plane (52.1% followed by distal step (31.3% and then mesial step (16.7%. The primary canine relationship was ranked in the descending order of prevalence as Class I (77.1%, Class II (13.5%, end-to-end (5.2% and Class III (4.2%. Normal overbite and normal overjet was observed in 50% and 81.3% of cases, respectively. Conclusion: This study provides an insight into the dental arch dimensions, occlusion, spacing and crowding in primary dentition in Iranian children. In most of the cases, primate space and flush terminal plane were observed.

  1. Full Mouth Reconstruction of a Bruxer with Severely Worn Dentition: A Clinical Report

    Science.gov (United States)

    Zeighami, Somayeh; Siadat, Hakimeh; Nikzad, Sakineh

    2015-01-01

    Tooth wear is attributed to several factors many of which often remain unidentified. Management of tooth wear is challenging in preventive and restorative dentistry. Correct assessment of occlusal vertical dimension, interocclusal rest space, and centric relation records are critical for successful treatment. In order to evaluate different treatment modalities and select the treatment of choice some information can be obtained from study casts and diagnostic wax-up. In order to achieve a predictable and desirable result, a systematic approach may be helpful. This paper describes the full mouth rehabilitation of a 36-year-old bruxer with severely worn dentition and other dental problems such as unfavorable restorations. A diagnostic work-up was performed and provisional restorations were made; then, they were clinically evaluated and adjusted based on the criteria dictating esthetics, phonetics, and vertical dimension. After endodontic therapy, clinical crown lengthening was performed. Two short implants were inserted in the posterior mandible. Custom-cast dowel cores and metal-ceramic restorations were fabricated and a full occlusal splint was used to protect the restorations. We ensured stable contacts on all teeth with equal intensity in centric relation and anterior guidance in accord with functional jaw movements. PMID:26229695

  2. Cutting blade dentitions in squaliform sharks form by modification of inherited alternate tooth ordering patterns

    Science.gov (United States)

    Underwood, Charlie; Johanson, Zerina; Smith, Moya Meredith

    2016-11-01

    The squaliform sharks represent one of the most speciose shark clades. Many adult squaliforms have blade-like teeth, either on both jaws or restricted to the lower jaw, forming a continuous, serrated blade along the jaw margin. These teeth are replaced as a single unit and successor teeth lack the alternate arrangement present in other elasmobranchs. Micro-CT scans of embryos of squaliforms and a related outgroup (Pristiophoridae) revealed that the squaliform dentition pattern represents a highly modified version of tooth replacement seen in other clades. Teeth of Squalus embryos are arranged in an alternate pattern, with successive tooth rows containing additional teeth added proximally. Asynchronous timing of tooth production along the jaw and tooth loss prior to birth cause teeth to align in oblique sets containing teeth from subsequent rows; these become parallel to the jaw margin during ontogeny, so that adult Squalus has functional tooth rows comprising obliquely stacked teeth of consecutive developmental rows. In more strongly heterodont squaliforms, initial embryonic lower teeth develop into the oblique functional sets seen in adult Squalus, with no requirement to form, and subsequently lose, teeth arranged in an initial alternate pattern.

  3. Full Mouth Reconstruction of a Bruxer with Severely Worn Dentition: A Clinical Report

    Directory of Open Access Journals (Sweden)

    Somayeh Zeighami

    2015-01-01

    Full Text Available Tooth wear is attributed to several factors many of which often remain unidentified. Management of tooth wear is challenging in preventive and restorative dentistry. Correct assessment of occlusal vertical dimension, interocclusal rest space, and centric relation records are critical for successful treatment. In order to evaluate different treatment modalities and select the treatment of choice some information can be obtained from study casts and diagnostic wax-up. In order to achieve a predictable and desirable result, a systematic approach may be helpful. This paper describes the full mouth rehabilitation of a 36-year-old bruxer with severely worn dentition and other dental problems such as unfavorable restorations. A diagnostic work-up was performed and provisional restorations were made; then, they were clinically evaluated and adjusted based on the criteria dictating esthetics, phonetics, and vertical dimension. After endodontic therapy, clinical crown lengthening was performed. Two short implants were inserted in the posterior mandible. Custom-cast dowel cores and metal-ceramic restorations were fabricated and a full occlusal splint was used to protect the restorations. We ensured stable contacts on all teeth with equal intensity in centric relation and anterior guidance in accord with functional jaw movements.

  4. CORRELATION BETWEEN DURATION OF BOTTLE-FEEDING AND DENTAL ARCH MEASUREMENT IN DECIDUOUS DENTITION

    Directory of Open Access Journals (Sweden)

    Meldo Mahniza

    2015-06-01

    Full Text Available The purpose of this study was to observe the correlation between duration of bottle feeding and dental arch measurement in deciduous dentition. Duration of bottle feeding was divided into 4 groups: ≤ 24 months, 25 – 36 months, 37 – 48 months, and > 48 months. The subjects were 120 kindergarten pupils, aged 3 – 5 years old. Measurements was done on the models of maxilla and mandible with digital caliper for the width and length of dental arch and using flexible curve for dental arch circumference. Pearson correlation showed a weak association for anterior arch width (r=0.206, posterior arch width (r=0.195, and anterior circumference (r=0.206 of maxilla and posterior arch width (r=0.279, anterior circumference (r=0.226 of mandible. One-way Anova was performed to analyze the differences of dental arch measurements among duration of bottle-feeding groups. The results showed that there were significant differences of dental arch measurements for anterior arch width of maxilla, posterior arch width of mandible, and anterior circumference of mandible (p<0,05.

  5. Evaluation of facial morphology and sagittal relationship between dental arches in primary and mixed dentition

    Directory of Open Access Journals (Sweden)

    Aline Traldi

    2015-08-01

    Full Text Available OBJECTIVE: To assess facial morphology (Pattern and sagittal relationship between dental arches (Class, and establish a potential association between them and the variables sex, age and ethnicity, among schoolchildren aged between 4 and 9 years old (mean age of 6.7 years in primary and mixed dentitions.METHODS: The sample comprised 875 children (457 males and 418 females attending schools in Descalvado, São Paulo, Brazil. An attempt was made with a view to establish a potential association between children's morphological features with sex, age and ethnicity.RESULTS: Descriptive analysis revealed a predominance of facial Pattern I (69.9 % and Class I (67.4 %. Statistical tests (p < 0.001 showed that Class I was more frequent among Pattern I children, whereas Class II prevailed among Pattern II, and Class III was frequent among Pattern I and III children. Ethnicity was the only variable associated with facial pattern.CONCLUSIONS: Results suggest that facial pattern and sagittal relationship between dental arches tend to be correlated. Ethnicity was associated with facial pattern, with Pattern I being the most recurrent among Caucasians and facial Pattern II being recurrent among Afro-descendant subjects.

  6. The hidden teeth of sloths: evolutionary vestiges and the development of a simplified dentition.

    Science.gov (United States)

    Hautier, Lionel; Gomes Rodrigues, Helder; Billet, Guillaume; Asher, Robert J

    2016-06-14

    Xenarthrans are unique among mammals in retaining simplified teeth that are rootless and homodont, which makes it difficult to determine dental homologies. We apply computerized tomography to prenatal developmental series of extant sloths, Bradypus and Choloepus, to further elucidate the patterns of morphological variation in their dentition. We also propose new criteria based on sequences of dental mineralization, and the presence of vestigial teeth, to distinguish between caniniforms and postcaniniforms. We report for the first time the presence of vestigial incisors in Bradypus. We also show the presence of a vestigial tooth in front of the lower caniniform in both extant sloth genera and the existence of two generations for the upper caniniform in Choloepus. The study of their sequence of mineralization indicates that the lower and upper caniniform teeth are not homologous in sloths, and suggests that upper caniniforms are not homologous between the two extant sloth genera. Our results show that assessing the developmental processes and functional constraints remains crucial to understand the dental variations observed in sloths, and more generally, tooth class homology issues in mammals. Applied to the tooth row of all extinct sloths, these developmental data illuminate a potentially ancestral dental formula for sloths.

  7. The hidden teeth of sloths: evolutionary vestiges and the development of a simplified dentition

    Science.gov (United States)

    Hautier, Lionel; Gomes Rodrigues, Helder; Billet, Guillaume; Asher, Robert J.

    2016-01-01

    Xenarthrans are unique among mammals in retaining simplified teeth that are rootless and homodont, which makes it difficult to determine dental homologies. We apply computerized tomography to prenatal developmental series of extant sloths, Bradypus and Choloepus, to further elucidate the patterns of morphological variation in their dentition. We also propose new criteria based on sequences of dental mineralization, and the presence of vestigial teeth, to distinguish between caniniforms and postcaniniforms. We report for the first time the presence of vestigial incisors in Bradypus. We also show the presence of a vestigial tooth in front of the lower caniniform in both extant sloth genera and the existence of two generations for the upper caniniform in Choloepus. The study of their sequence of mineralization indicates that the lower and upper caniniform teeth are not homologous in sloths, and suggests that upper caniniforms are not homologous between the two extant sloth genera. Our results show that assessing the developmental processes and functional constraints remains crucial to understand the dental variations observed in sloths, and more generally, tooth class homology issues in mammals. Applied to the tooth row of all extinct sloths, these developmental data illuminate a potentially ancestral dental formula for sloths. PMID:27297516

  8. Dental Health Behaviors, Dentition, and Mortality in the Elderly: The Leisure World Cohort Study

    Directory of Open Access Journals (Sweden)

    Annlia Paganini-Hill

    2011-01-01

    Full Text Available In the last decade the effect of oral health on the general health and mortality of elderly people has attracted attention. We explored the association of dental health behaviors and dentition on all-cause mortality in 5611 older adults followed from 1992 to 2009 (median=9 years and calculated risk estimates using Cox regression analysis in men and women separately. Toothbrushing at night before bed, using dental floss everyday, and visiting the dentist were significant risk factors for longevity. Never brushing at night increased risk 20–35% compared with brushing everyday. Never flossing increased risk 30% compared with flossing everyday. Not seeing a dentist within the last 12 months increased risk 30–50% compared with seeing a dentist two or more times. Mortality also increased with increasing number of missing teeth. Edentulous individuals (even with dentures had a 30% higher risk of death compared with those with 20+ teeth. Oral health behaviors help maintain natural, healthy and functional teeth but also appear to promote survival in older adults.

  9. Factors associated with dental caries in the primary dentition of children with cerebral palsy

    Directory of Open Access Journals (Sweden)

    Luana Leal Roberto

    2012-10-01

    Full Text Available The aim of this study was to investigate factors associated with caries experience in the primary dentition of one- to five-year-old children with cerebral palsy. A total of 266 dental records were examined, and caries experience was measured by dmft. The following variables were also analyzed: gender, oral hygiene, history of gastroesophageal reflux, use of medications for gastroesophageal reflux, gingival status, sugar intake and reports of polyuria, excessive thirst and xerostomia. For analysis purposes, the individuals were categorized as those with and without caries experience and subcategorized into the following age groups: one year; two to three years; and four to five years. After bivariate analysis, variables with a p-value < 0.25 were selected for incorporation into the Poisson regression models. Considering the limitations of the protocol, the level of oral hygiene perceived on the first appointment was the only factor associated with caries experience among two-to-fiveyear-old children with cerebral palsy.

  10. Permanent Magnet Boosted Modular Switched Reluctance Motor

    Directory of Open Access Journals (Sweden)

    SZABÓ Loránd

    2016-10-01

    Full Text Available This paper deals with the analyses of a novel motor structure obtained by boosting with permanent magnets a formerly studied modular switched reluctance motor. Upon dynamic simulation results the improvements of the proposed motor are emphasized.

  11. Practical considerations for permanent total enclosures

    Energy Technology Data Exchange (ETDEWEB)

    Worrall, M. [Amcec Adsorption Systems, Schaumburg, IL (United States)

    1997-12-31

    This paper considers some of the practical consideration of Permanent Total Enclosures (PTEs) for gravure printing facilities. In particular the dispersion of fugitive losses from the presses by thermal air currents generated by heat from the press dryers.

  12. 78 FR 14122 - Revocation of Permanent Variances

    Science.gov (United States)

    2013-03-04

    ... Occupational Safety and Health Administration Revocation of Permanent Variances AGENCY: Occupational Safety and Health Administration (OSHA), Labor. ACTION: Notice of revocation. SUMMARY: With this notice, OSHA is... into consideration these newly corrected cross references. DATES: The effective date of the...

  13. Permanent traffic counters maintained by the NMDOT

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — A point dataset representing the permanent traffic counters maintained by the NMDOT. Event mapped dataset by LRS info provided by Traffic group.

  14. Novel Switched Flux Permanent Magnet Machine Topologies

    Institute of Scientific and Technical Information of China (English)

    诸自强

    2012-01-01

    This paper overviews various switched flux permanent magnet machines and their design and performance features,with particular emphasis on machine topologies with reduced magnet usage or without using magnet,as well as with variable flux capability.

  15. Computing matrix permanent with collective boson operators

    CERN Document Server

    Huh, Joonsuk

    2016-01-01

    Computing permanents of matrices are known to be a classically hard problem that the computational cost grows exponentially with the size of the matrix increases. So far, there exist a few classical algorithms to compute the matrix permanents in deterministic and in randomized ways. By exploiting the series expansion of products of boson operators regarding collective boson operators, a generalized algorithm for computing permanents is developed that the algorithm can handle the arbitrary matrices with repeated columns and rows. In a particular case, the formula is reduced to Glynn's form. Not only the algorithm can be used for a deterministic direct calculation of the matrix permanent but also can be expressed as a sampling problem like Gurvits's randomized algorithm.

  16. [Permanent education in health: a review].

    Science.gov (United States)

    Miccas, Fernanda Luppino; Batista, Sylvia Helena Souza da Silva

    2014-02-01

    To undertake a meta-synthesis of the literature on the main concepts and practices related to permanent education in health. A bibliographical search was conducted for original articles in the PubMed, Web of Science, LILACS, IBECS and SciELO databases, using the following search terms: "public health professional education", "permanent education", "continuing education", "permanent education health". Of the 590 articles identified, after applying inclusion and exclusion criteria, 48 were selected for further analysis, grouped according to the criteria of key elements, and then underwent meta-synthesis. The 48 original publications were classified according to four thematic units of key elements: 1) concepts, 2) strategies and difficulties, 3) public policies and 4) educational institutions. Three main conceptions of permanent education in health were found: problem-focused and team work, directly related to continuing education and education that takes place throughout life. The main strategies for executing permanent education in health are discussion, maintaining an open space for permanent education , and permanent education clusters. The most limiting factor is mainly related to directly or indirect management. Another highlight is the requirement for implementation and maintenance of public policies, and the availability of financial and human resources. The educational institutions need to combine education and service aiming to form critical-reflexive graduates. The coordination between health and education is based as much on the actions of health services as on management and educational institutions. Thus, it becomes a challenge to implement the teaching-learning processes that are supported by critical-reflexive actions. It is necessary to carry out proposals for permanent education in health involving the participation of health professionals, teachers and educational institutions. To undertake a meta-synthesis of the literature on the main concepts and

  17. Three-dimensional analysis of the uniqueness of the anterior dentition in orthodontically treated patients and twins.

    Science.gov (United States)

    Franco, A; Willems, G; Souza, P H C; Tanaka, O M; Coucke, W; Thevissen, P

    2017-02-26

    Dental uniqueness can be proven if no perfect match in pair-wise morphological comparisons of human dentitions is detected. Establishing these comparisons in a worldwide random population is practically unfeasible due to the need for a large and representative sample size. Sample stratification is an option to reduce sample size. The present study investigated the uniqueness of the human dentition in randomly selected subjects (Group 1), orthodontically treated patients (Group 2), twins (Group 3), and orthodontically treated twins (Group 4) in comparison with a threshold control sample of identical dentitions (Group 5). The samples consisted of digital cast files (DCF) obtained through extraoral 3D scanning. A total of 2.013 pair-wise morphological comparisons were performed (Group 1 n=110, Group 2 n=1.711, Group 3 n=172, Group 4 n=10, Group 5 n=10) with Geomagic Studio(®) (3D Systems(®), Rock Hill, SC, USA) software package. Comparisons within groups were performed quantifying the morphological differences between DCF in Euclidean distances. Comparisons between groups were established applying One-way ANOVA. To ensure fair comparisons a post-hoc Power Analysis was performed. ROC analysis was applied to distinguish unique from non-unique dentures. Identical DCF were not detected within the experimental groups (from 1 to 4). The most similar DCF had Euclidian distance of 5.19mm in Group 1, 2.06mm in Group 2, 2.03mm in Group 3, and 1.88mm in Group 4. Groups 2 and 3 were statistically different from Group 5 (p<0.05). Statistically significant difference between Group 4 and 5 revealed to be possible including more pair-wise comparisons in both groups. The ROC analysis revealed sensitivity rate of 80% and specificity between 66.7% and 81.6%. Evidence to sustain the uniqueness of the human dentition in random and stratified populations was observed in the present study. Further studies testing the influence of the quantity of tooth material on morphological difference

  18. Micromachined permanent magnets and their MEMS applications

    Science.gov (United States)

    Cho, Hyoung Jin

    2002-01-01

    In this research, new micromachined permanent magnets have been proposed, developed and characterized for MEMS applications. In realizing micromachined permanent magnets, a new electroplating technique using external magnetic field and a bumper filling technique using a photolithographically defined mold with resin bonded magnetic particles have been developed. The newly developed micromachining techniques allow thick film-type permanent magnet components to be integrated to magnetic MEMS devices with dimensional control and alignment. Permanent magnet arrays with the dimensions ranging from 30 mum to 200 mum have been developed with an energy density up to 2.7 kJ/m3 in precisely defined forms in the micro scale. For the applications of the permanent magnets developed in this work, three novel magnetic MEMS devices such as a bi-directional magnetic actuator, a magnetically driven optical scanner, and a magnetic cell separator have been successfully realized. After design and modeling, each device has been fabricated and fully characterized. The bi-directional actuator with the electroplated permanent magnet array has achieved bi-directional motion clearly and shown good agreement with the analytical and simulated models. The optical scanner has shown linear bi-directional response under static actuation and stable bi-directional scanning performance under dynamic actuation. As a potential BioMEMS application of the developed permanent magnet, the prototype magnetic cell separator using the electroplated permanent magnet strip array has been proposed and demonstrated for magnetic bead patterning. In conclusion, new thick film-type, electroplated CoNiMnP and epoxy resin bonded Sr-ferrite permanent magnets have been developed and characterized, and then, three new magnetic MEMS devices using the permanent magnets such as a bi-directional magnetic actuator, an optical scanner and a magnetic cell separator have been realized in this research. The new micromachined

  19. Time of mineralization of permanent teeth in children and adolescents in Gaborone, Botswana.

    Science.gov (United States)

    Cavrić, Jelena; Vodanović, Marin; Marušić, Ana; Galić, Ivan

    2016-01-01

    The mineralization sequence of permanent dentition can be used to assess the stage of development and age of individuals. The most commonly used methods are based on the assessment of developmental stages of target groups of teeth on one side of the lower jaw. When compared with the rest of the world, fewer studies have been done on dental age in Sub-Saharan Africa, particularly in the region of Southern Africa. The aim of this study was to determine the chronology of mineralization of permanent teeth by the evaluation of developmental stages according to the Demirjian's method from 1973 and to evaluate dental age by using sex-specific self-weighted scores for dental stages and 50th percentile conversion tables of total maturity scores of seven mandibular teeth. We used a sample of panoramic radiographs (OPTs) of black African children and adolescents from the city of Gaborone, Botswana, with the aim of forming an appropriate sample to evaluate the development of the teeth in this socio-geographic environment. The final sample consisted of 1760 OPTs (807 males and 953 females) of individuals aged 6-23 years. The developmental stages of the all permanent teeth in the left side of the maxilla and the mandible were evaluated. Comparing the maxilla and the mandible, we found similar development within different stages for most of the teeth. In comparison to the average age at each stage of development, including the third molars between males and females, it is evident that females are slightly faster in developing permanent teeth, but without statistical significance for most of the developmental stages. Applying 50th percentile conversion tables for calculating the dental age for the first seven mandibular teeth, 616 OPTs of the children (299 males and 317 females), aged 6.08-16.80 years, were evaluated and their dental age was calculated. Mean dental age was overestimated in comparison to chronological age by 1.25±1.11 years and 0.72±1.02 years for males and

  20. Occlusal morphology of permanent mandibular first and second molars in Gujarati population.

    Science.gov (United States)

    Dholia, Bhavik; Manjunatha, Bhari Sharanesha

    2015-01-01

    Dental identification has been used since long time for disaster victim identification protocol. There is a difference of opinion regarding whether ethnicity influences dental morphology or not. Few studies have shown the associations between these dental features and crown traits in humans using quantitative methods. The present study is an attempt to find correlation of occlusal morphology of Gujarati population with forensic Odontology. To study different occlusal morphology of permanent mandibular first and second molars in Gujarati Population. This study comprised of a total of 100 participants of Gujarati origin, selected by random sampling method. Total number of cusps and groove patterns of mandibular first and second molar were examined clinically and photographs of the same were taken. A descriptive statistics, Chi-square test and Student t-test were used for analysis of data. Mandibular first molar with 5 cusps in 71%, 4 cusps in 18% and 6 cusps in 11% were noted in the study. Mandibular first molars with "+" groove pattern in 39.5% and "Y" groove pattern in 60.5% were recorded. Mandibular second molar with 5 cusps in 6.5% and 4 cusps in 93.5% were recorded in the study. Mandibular second molars with "+" groove pattern in 93.5% and "Y" groove pattern in 6.5% were recorded. The most common occlusal morphology in permanent mandibular first molar is "5 cusp" and "Y" groove pattern in about 47% and for second molar is "4 cusp" and "+" groove pattern in 88.5% of Gujarati population. It may be concluded that variation in degree of expression and frequency of teeth in dentitions of different populations is different, which may help in forensic identification.

  1. Occlusal morphology of permanent mandibular first and second molars in Gujarati population

    Directory of Open Access Journals (Sweden)

    Bhavik Dholia

    2015-01-01

    Full Text Available Background: Dental identification has been used since long time for disaster victim identification protocol. There is a difference of opinion regarding whether ethnicity influences dental morphology or not. Few studies have shown the associations between these dental features and crown traits in humans using quantitative methods. The present study is an attempt to find correlation of occlusal morphology of Gujarati population with forensic Odontology. Aim: To study different occlusal morphology of permanent mandibular first and second molars in Gujarati Population. Materials and Methods: This study comprised of a total of 100 participants of Gujarati origin, selected by random sampling method. Total number of cusps and groove patterns of mandibular first and second molar were examined clinically and photographs of the same were taken. A descriptive statistics, Chi-square test and Student t-test were used for analysis of data. Results: Mandibular first molar with 5 cusps in 71%, 4 cusps in 18% and 6 cusps in 11% were noted in the study. Mandibular first molars with "+" groove pattern in 39.5% and "Y" groove pattern in 60.5% were recorded. Mandibular second molar with 5 cusps in 6.5% and 4 cusps in 93.5% were recorded in the study. Mandibular second molars with "+" groove pattern in 93.5% and "Y" groove pattern in 6.5% were recorded. Conclusion: The most common occlusal morphology in permanent mandibular first molar is "5 cusp" and "Y" groove pattern in about 47% and for second molar is "4 cusp" and "+" groove pattern in 88.5% of Gujarati population. It may be concluded that variation in degree of expression and frequency of teeth in dentitions of different populations is different, which may help in forensic identification.

  2. Occlusal morphology of permanent mandibular first and second molars in Gujarati population

    Science.gov (United States)

    Dholia, Bhavik; Manjunatha, Bhari Sharanesha

    2015-01-01

    Background: Dental identification has been used since long time for disaster victim identification protocol. There is a difference of opinion regarding whether ethnicity influences dental morphology or not. Few studies have shown the associations between these dental features and crown traits in humans using quantitative methods. The present study is an attempt to find correlation of occlusal morphology of Gujarati population with forensic Odontology. Aim: To study different occlusal morphology of permanent mandibular first and second molars in Gujarati Population. Materials and Methods: This study comprised of a total of 100 participants of Gujarati origin, selected by random sampling method. Total number of cusps and groove patterns of mandibular first and second molar were examined clinically and photographs of the same were taken. A descriptive statistics, Chi-square test and Student t-test were used for analysis of data. Results: Mandibular first molar with 5 cusps in 71%, 4 cusps in 18% and 6 cusps in 11% were noted in the study. Mandibular first molars with “+” groove pattern in 39.5% and “Y” groove pattern in 60.5% were recorded. Mandibular second molar with 5 cusps in 6.5% and 4 cusps in 93.5% were recorded in the study. Mandibular second molars with “+” groove pattern in 93.5% and “Y” groove pattern in 6.5% were recorded. Conclusion: The most common occlusal morphology in permanent mandibular first molar is “5 cusp” and “Y” groove pattern in about 47% and for second molar is “4 cusp” and “+” groove pattern in 88.5% of Gujarati population. It may be concluded that variation in degree of expression and frequency of teeth in dentitions of different populations is different, which may help in forensic identification. PMID:26005303

  3. Sporadic hemiplegic migraine with permanent neurological deficits.

    Science.gov (United States)

    Schwedt, Todd J; Zhou, Jiying; Dodick, David W

    2014-01-01

    By definition, the neurologic impairments of hemiplegic migraine are reversible. However, a few cases of permanent neurologic deficits associated with hemiplegic migraine have been reported. Herein, we present the case of a patient with permanent impairments because of hemiplegic migraine despite normalization of associated brain magnetic resonance imaging abnormalities. Cases like these suggest the need to consider aggressive prophylactic therapy for patients with recurrent hemiplegic migraine attacks.

  4. Macroscopic Simulation of Isotropic Permanent Magnets

    OpenAIRE

    Bruckner, Florian; Abert, Claas; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2015-01-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the...

  5. Quantum Permanents and Hafnians via Pfaffians

    Science.gov (United States)

    Jing, Naihuan; Zhang, Jian

    2016-10-01

    Quantum determinants and Pfaffians or permanents and Hafnians are introduced on the two-parameter quantum general linear group. Fundamental identities among quantum Pf, Hf, and det are proved in the general setting. We show that there are two special quantum algebras among the quantum groups, where the quantum Pfaffians have integral Laurent polynomials as coefficients. As a consequence, the quantum Hafnian is computed by a closely related quantum permanent and identical to the quantum Pfaffian on this special quantum algebra.

  6. Permanent magnet system of alpha magnetic spectrometer

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Alpha magnetic spectrometer (AMS) is the first large magnetic spectrometer in space. Its precursor flight was completed successfully in June 1998. The key part of AMS is the permanent magnet system, which was built by the Institute of Electric Engineering, the Institute of High Energy Physics and the Chinese Academy of Launch Vehicle Technology. This system includes a permanent magnet made of high grade NdFeB and a support structure. The unique design of the permanent magnet based on the magic ring fulfills the severe requirements on the magnetic field leakage and the dipole moment for space experiments. The permanent magnet weighs about 2 tons, and provides a geometric acceptance of 0.6 m2 ·sr and an analyzing power BL2 of 0.135 T·m2. It works up to 40℃ without demagnetization. The main structure is a thin double shell, which undergoes the strong magnetic force and torque of the permanent magnet, as well as the large load during launching and landing. The permanent magnet system fulfills the requirements from AMS, and satisfies the strict safety standards of NASA.

  7. Permanent magnet system of alpha magnetic spectrometer

    Institute of Scientific and Technical Information of China (English)

    陈和生

    2000-01-01

    Alpha magnetic spectrometer (AMS) is the first large magnetic spectrometer in space. Its precursor flight was completed successfully in June 1998. The key part of AMS is the permanent magnet system, which was built by the Institute of Electric Engineering, the Institute of High Energy Physics and the Chinese Academy of Launch Vehicle Technology. This system includes a permanent magnet made of high grade NdFeB and a support structure. The unique design of the permanent magnet based on the magic ring fulfills the severe requirements on the magnetic field leakage and the dipole moment for space experiments. The permanent magnet weighs about 2 tons, and provides a geometric acceptance of 0.6 m2·sr and an analyzing power BL2 of 0.135 T·m2. It works up to 40℃ without demagnetization. The main structure is a thin double shell, which undergoes the strong magnetic force and torque of the permanent magnet, as well as the large load during launching and landing. The permanent magnet system fulfills the requirem

  8. Workplace bullying a risk for permanent employees.

    Science.gov (United States)

    Keuskamp, Dominic; Ziersch, Anna M; Baum, Fran E; Lamontagne, Anthony D

    2012-04-01

    We tested the hypothesis that the risk of experiencing workplace bullying was greater for those employed on casual contracts compared to permanent or ongoing employees. A cross-sectional population-based telephone survey was conducted in South Australia in 2009. Employment arrangements were classified by self-report into four categories: permanent, casual, fixed-term and self-employed. Self-report of workplace bullying was modelled using multiple logistic regression in relation to employment arrangement, controlling for sex, age, working hours, years in job, occupational skill level, marital status and a proxy for socioeconomic status. Workplace bullying was reported by 174 respondents (15.2%). Risk of workplace bullying was higher for being in a professional occupation, having a university education and being separated, divorced or widowed, but did not vary significantly by sex, age or job tenure. In adjusted multivariate logistic regression models, casual workers were significantly less likely than workers on permanent or fixed-term contracts to report bullying. Those separated, divorced or widowed had higher odds of reporting bullying than married, de facto or never-married workers. Contrary to expectation, workplace bullying was more often reported by permanent than casual employees. It may represent an exposure pathway not previously linked with the more idealised permanent employment arrangement. A finer understanding of psycho-social hazards across all employment arrangements is needed, with equal attention to the hazards associated with permanent as well as casual employment. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

  9. EDITORIAL: Permanent revolution - or evolution?

    Science.gov (United States)

    Dobson, Ken

    1998-03-01

    Honorary Editor It was that temporary Bolshevik Leon Trotsky who developed the principle of `permanent revolution', a principle that perhaps characterizes the recent history of education in (south) Britain more than does, say, principles traditionally associated with the Conservative or Labour parties. As this editorial is being written, changes are being made to primary school education, and the long-awaited details of the post-Dearing reorganizing of post-16 education are yet to hit the overful bookshelves and filing cabinets of school heads and examination board officials. But something unique has happened recently which might have surprised even Trotsky. The Secretary of State for Education has set up targets for primary school pupils' attainment and threatened (or promised) to resign if they are not met within the lifetime of our newly elected parliament. Of course, if Mr Blunkett is still in a position to resign at that stage he will have been the longest serving Secretary of State since time immemorial. But we should not carp: this is truly a revolutionary idea. Not the promise to resign - although this idea is not so fashionable now as it once was. The revolutionary idea is that a major change to an educational process is actually being made that carries with it a predicted and testable outcome. By contrast, when school physics was refreshed a generation ago by the introduction of Nuffield courses at both pre- and post-16 stages, no `targets' were set. I and many other physics teachers certainly preferred teaching these to teaching their predecessor syllabuses, and might even dare to assert that the pupils liked them too. But we still don't really know whether or not they learned more - or even better - physics. Very little happened as far as the outside world was concerned: the usual fraction of students gave up physics at the usual ages, and those who were examined didn't really get a better reward for their more up-to-date and more enjoyably learned

  10. Early removal of odontoma resulting in spontaneous eruption of the impacted teeth

    Directory of Open Access Journals (Sweden)

    Achmad Harijadi

    2010-06-01

    Full Text Available Background: Compound odontomas in the anterior maxilla during mixed dentition frequently cause obstruction to the eruption pathway of permanent upper anterior teeth. Removal of the odontomas may or may not lead to spontaneous eruption of the impacted teeth depending on the age when the surgery is performed, the size of the lesion, and the stage of tooth development of the involved teeth. Purpose: This paper attempts to emphasize the importance of early removal of compound odontoma to enable spontaneous eruption of the affected teeth. Case: A case of odontoma in the anterior maxilla causing failure of eruption and delayed root formation of upper right permanent lateral incisor and canine in a 10-year-old male patient is presented. Case management: The odontoma was surgically removed under general anesthesia and histology result confirmed the diagnosis of compound odontoma. A three-year post surgical follow up showed spontaneous eruption as well as continued root formation of the two affected teeth. Conclusion: Removal of odontoma may lead to spontaneous eruption of the affected teeth if their root development are not completed.Latar belakang: Compound odontoma pada daerah anterior maksila pada masa geligi pergantian sering menyebabkan hambatan erupsi pada gigi permanen penggantinya. Kemungkinan terjadinya erupsi spontan gigi permanen yang impaksi setelah pengambilan odontoma tergantung dari: umur penderita pada saat dilakukan operasi, ukuran lesi odontoma dan tahapan perkembangan gigi permanen yang terlibat. Tujuan: Laporan kasus ini ingin menekankan pentingnya pengambilan compound odontoma sedini mungkin untuk memberi kesempatan tumbuhnya gigi permanen yang terlibat dan erupsi secara spontan. Kasus: Ditampilkan sebuah kasus compound odontoma pada regio maksila anterior menyebabkan gagalnya erupsi dan terlambatnya pembentukan akar gigi insisif kedua dan kaninus permanent rahang atas kanan pada penderita anak laki-laki berumur 10 tahun

  11. Decoronation for the management of an ankylosed young permanent tooth.

    Science.gov (United States)

    Sapir, Shabtai; Shapira, Joseph

    2008-02-01

    Replacement resorption rate is a variable process, and is dependent on age, basal metabolic rate, extra-alveolar time, treatment prior to replantation, amount of root dentin, severity of trauma, and extent of periodontal ligament necrosis. In patients 7-16 years old a tooth is lost 3-7 years after the onset of root resorption. The complications that may develop as a consequence of ankylosis of a permanent incisor in children are due to the inevitable early loss of the traumatized tooth and local arrest of alveolar bone development. An ankylosed tooth should be removed before the changes become so pronounced that they compromise future prosthetic treatment. The treatment options may involve: interceptive regenerative treatment, early extraction of the ankylosed tooth, orthodontic space closure, intentional replantation, extraction of the ankylosed tooth followed with immediate ridge augmentation/preservation, auto-transplantation, single tooth dento-osseous osteotomy, and decoronation. The purpose of this article was to review the considerations involved in the decision-making concerning the use of the decoronation technique for the treatment of a permanent incisor diagnosed as ankylosed.

  12. Follow-up of permanent hearing impairment in childhood.

    Science.gov (United States)

    Della Volpe, A; De Lucia, A; Pastore, V; Bracci Laudiero, L; Buonissimo, I; Ricci, G

    2016-02-01

    Programmes for early childhood childhood hearing impairment identification allows to quickly start the appropriate hearing aid fitting and rehabilitation process; nevertheless, a large number of patients do not join the treatment program. The goal of this article is to present the results of a strategic review of the strengths, weaknesses, opportunities and threats connected with the audiologic/prosthetic/language follow-up process of children with bilateral permanent hearing impairment. Involving small children, the follow-up includes the involvement of specialised professionals of a multidisciplinary team and a complex and prolonged multi-faced management. Within the framework of the Italian Ministry of Health project CCM 2013 "Preventing Communication Disorders: a Regional Program for Early Identification, Intervention and Care of Hearing Impaired Children", the purpose of this analysis was to propose recommendations that can harmonise criteria for outcome evaluation and provide guidance on the most appropriate assessment methods to be used in the follow-up course of children with permanent hearing impairment. © Copyright by Società Italiana di Otorinolaringologia e Chirurgia Cervico-Facciale.

  13. Research on early quantitating artificial demineralization of bovine permanent teeth using the average gray value of optical coherence tomography images%利用光学相干断层图像平均灰度值定量研究牛恒牙早期人工脱矿

    Institute of Scientific and Technical Information of China (English)

    徐延勇; 姚晖; 李燕妮; 连小丽; 张林朴; 王冠华; 代晓华

    2010-01-01

    目的 研究经酸蚀脱矿后牛恒牙光学相干断层图像平均灰度值的变化,探讨平均灰度值作为一个参数指标定量检测牛恒牙早期脱矿的可行性.方法 以正常离体牛恒牙为样本,采用凝胶酸蚀法制备人工脱矿模型;用光学相干断层摄影术对人工脱矿模型扫描成像,利用Matlab软件计算不同酸蚀时间脱矿区牙体层110 μm范围内的平均灰度值.将测得图像灰度和归一化后图像灰度,分别进行单因素方差分析.结果 牙体表层110 μm范围内不同时间酸蚀脱矿区的平均灰度值从大到小依次为30 min酸蚀脱矿区、1O min酸蚀脱矿区、0 min酸蚀脱矿区,图像灰度归一化后做单因素方差分析,P<0.05.结论 牙体表层110 μm范围内不同酸蚀时间脱矿区平均灰度值差异有统计学意义,并随脱矿时间增加而增大,即平均灰度值可以用于光学相干断层摄影术定量检测牙齿的早期脱矿.光学相干断层图像灰度归一化使得不同酸蚀脱矿区的平均灰度值更有可比性,减小了由于样本之间差异引起的误差,提高了平均灰度值作为参数指标定量检测牙齿早期脱矿的可靠性.%Objective To investigate the feasibility of the average gray value as a parameter index for early quantification detection of artificial demineralization by studying the changes of average gray value on optical coherence tomography (OCT) images of bovine permanent teeth etched.Methods Early stage of artificial demineralization mould was created by etching the experimental normal isolated bovine permanent teeth surface.Images of the artificial demineralization mould were obtained by OCT,and then the average gray value within the 110 μm under the teeth surface was calculated by Matlab software.The gray value and the normalized gray value were analyzed by ANOVA,respectively.Results On the OCT images,the average gray value within the 110 μm under the teeth surface form high to low were the

  14. Incidence of dental caries in primary dentition and risk factors: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Patrícia CORRÊA-FARIA

    2016-01-01

    Full Text Available Abstract The objectives of this prospective, longitudinal, population-based study were to estimate the incidence of dental caries in the primary dentition, identify risk factors and determine the proportion of children receiving dental treatment, through a two-year follow up. The first dental exam was conducted with 381 children aged one to five years, at health centers during immunization campaigns; 184 of them had dental caries and 197 had no caries experience. The second exam was carried out two years later at a nursery or at home with the same individuals who participated in the first exam. The diagnosis of dental caries was performed using the dmft criteria. Parents were interviewed regarding socioeconomic indicators. Descriptive, bivariate and adjusted Poisson regression analyses were performed. Among the 381 children, 234 were reexamined after two years (non-exposed: 139; exposed: 95. The overall incidence of dental caries was 46.6%. The greatest incidence of dental caries was found in the group of children with previous caries experience (61.1%. Among the children without dental caries in the first exam, 36.7% exhibited caries in the second exam. The majority of children (72.6% received no treatment for carious lesions in the two-year interval between examinations. Children with previous dental caries (RR: 1.52, 95%CI: 1.12–2.05 had a greater risk of developing new lesions, compared with the children without previous dental caries. The incidence of dental caries was high and most of children’s caries were untreated. Previous caries experience is a risk factor for developing new carious lesions in children.

  15. Current knowledge of tooth development: patterning and mineralization of the murine dentition.

    Science.gov (United States)

    Catón, Javier; Tucker, Abigail S

    2009-04-01

    The integument forms a number of different types of mineralized element, including dermal denticles, scutes, ganoid scales, elasmoid scales, fin rays and osteoderms found in certain fish, reptiles, amphibians and xenarthran mammals. To this list can be added teeth, which are far more widely represented and studied than any of the other mineralized elements mentioned above, and as such can be thought of as a model mineralized system. In recent years the focus for studies on tooth development has been the mouse, with a wealth of genetic information accrued and the availability of cutting edge techniques. It is the mouse dentition that this review will concentrate on. The development of the tooth will be followed, looking at what controls the shape of the tooth and how signals from the mesenchyme and epithelium interact to lead to formation of a molar or incisor. The number of teeth generated will then be investigated, looking at how tooth germ number can be reduced or increased by apoptosis, fusion of tooth germs, creation of new tooth germs, and the generation of additional teeth from existing tooth germs. The development of mineralized tissue will then be detailed, looking at how the asymmetrical deposition of enamel is controlled in the mouse incisor. The continued importance of epithelial-mesenchymal interactions at these later stages of tooth development will also be discussed. Tooth anomalies and human disorders have been well covered by recent reviews, therefore in this paper we wish to present a classical review of current knowledge of tooth development, fitting together data from a large number of recent research papers to draw general conclusions about tooth development.

  16. Associations between orbicularis oris thickness and skeletal and dental variables in mixed dentition

    Directory of Open Access Journals (Sweden)

    Taís de Souza Barbosa

    Full Text Available AIM: To evaluate the association between orbicularis oris thickness and skeletal and dental variables in children with mixed dentition. MATERIAL AND METHOD: A convenience sample of 22 children, aged 7 to 12 years, with skeletal Class I and Class II malocclusion and subdivisions were selected. The upper and lower fascicles of the orbicularis oris thicknesses were measured using ultrasound (US by one calibrated examiner, at rest and in the contracted state. Cephalometric radiograph measurements of the hard and soft tissues were calculated by one trained examiner. The results were analyzed by the Pearson and Spearman coefficients. RESULT: The upper and lower fascicles of the orbicularis oris in the contracted state showed a negative correlation with the distance between Ricketts' E-line and the labrale superius (E ┴ Ls. There were positive correlations between the lower face height and the distance between the AB plane and the labrale superius (AB-Ls and between the ANB angle and the distance between E ┴ Ls and Ricketts' E-line and the labrale inferius (E ┴ Li. The lower-incisor distance from the N-Pg plane correlated positively with the distance between AB-Ls and the distance between the E ┴ Ls and E ┴ Li. Overbite and interincisal angle were negatively correlated with the distance between the pogonion and the soft tissue pogonion and the distance between E ┴ Li, respectively. CONCLUSION: Skeletal and dental variables were associated with upper and lower lip position and pogonion thickness, while the upper and lower fascicles of the orbicularis oris thicknesses in the contracted state were associated only with upper lip retrusion.

  17. Vertebral morphology, dentition, age, growth, and ecology of the large lamniform shark Cardabiodon ricki

    Directory of Open Access Journals (Sweden)

    Michael G. Newbrey

    2015-12-01

    Full Text Available Cardabiodon ricki and Cardabiodon venator were large lamniform sharks with a patchy but global distribution in the Cenomanian and Turonian. Their teeth are generally rare and skeletal elements are less common. The centra of Cardabiodon ricki can be distinguished from those of other lamniforms by their unique combination of characteristics: medium length, round articulating outline with a very thick corpus calcareum, a corpus calcareum with a laterally flat rim, robust radial lamellae, thick radial lamellae that occur in low density, concentric lamellae absent, small circular or subovate pores concentrated next to each corpus calcareum, and papillose circular ridges on the surface of the corpus calcareum. The large diameter and robustness of the centra of two examined specimens suggest that Cardabiodon was large, had a rigid vertebral column, and was a fast swimmer. The sectioned corpora calcarea show both individuals deposited 13 bands (assumed to represent annual increments after the birth ring. The identification of the birth ring is supported in the holotype of Cardabiodon ricki as the back-calculated tooth size at age 0 is nearly equal to the size of the smallest known isolated tooth of this species. The birth ring size (5–6.6 mm radial distance [RD] overlaps with that of Archaeolamna kopingensis (5.4 mm RD and the range of variation of Cretoxyrhina mantelli (6–11.6 mm RD from the Smoky Hill Chalk, Niobrara Formation. The revised, reconstructed lower jaw dentition of the holotype of Cardabiodon ricki contains four anterior and 12 lateroposterior files. Total body length is estimated at 5.5 m based on 746 mm lower jaw bite circumference reconstructed from associated teeth of the holotype.

  18. Awareness of Stem cells & Health Implications of SHED found in Pediatric Dentition among Indian Population.

    Science.gov (United States)

    Goomer, Pallvi; Sidhu, Arshpreet Kaur; Tuli, Preety; Kansal, Shinam; Bansal, Kanishka; Thakre, Gauri R

    2014-02-01

    Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED (stem cells from human exfoliated deciduous teeth) were identified to be a population of highly proliferative, clonogenic cells capable of differentiating into a variety of cell types including neural cells, adipocytes, and odontoblasts. The present study was carried out to assess the knowledge, awareness & attitude of parents visiting various dental clinics in tricity area of india regarding stem cells from primary teeth and their potential health benefits. A total of 250 parents of pediatric patients seeking dental treatment at various dental clinics in tricity area were included in the study. Parents were personally interviewed with a questionnaire and their responses were immediately computed. Among 250 parents only 95(62%) had knowledge regarding stem cells. While only 47(18.8) were informed regarding stem cells from baby teeth & their benefits. Maximum subjects were informed through internet 21(44.6%) followed by information through friends(23.4%) and dentist(21.2%). Very few were informed through magazines, newspaper and only one (2.1%) person was informed by television. It is important to create more awareness among the populace of our country about the potential health benefits of stem cells from primary teeth. Dentist should educate parents, caregivers and teachers regarding SHED & its benefits, ensuring good health for every Indian child and hence health of future citizens. How to cite the article: Goomer P, Sidhu AK, Tuli P, Kansal S, Bansal K, Thakre GR. Awareness of Stem cells & Health Implications of SHED found in Pediatric Dentition among Indian Population. J Int Oral Health 2014;6(1):44-7.

  19. Incidence of dental caries in primary dentition and risk factors: a longitudinal study.

    Science.gov (United States)

    Corrêa-Faria, Patrícia; Paixão-Gonçalves, Suzane; Paiva, Saul Martins; Pordeus, Isabela Almeida

    2016-05-20

    The objectives of this prospective, longitudinal, population-based study were to estimate the incidence of dental caries in the primary dentition, identify risk factors and determine the proportion of children receiving dental treatment, through a two-year follow up. The first dental exam was conducted with 381 children aged one to five years, at health centers during immunization campaigns; 184 of them had dental caries and 197 had no caries experience. The second exam was carried out two years later at a nursery or at home with the same individuals who participated in the first exam. The diagnosis of dental caries was performed using the dmft criteria. Parents were interviewed regarding socioeconomic indicators. Descriptive, bivariate and adjusted Poisson regression analyses were performed. Among the 381 children, 234 were reexamined after two years (non-exposed: 139; exposed: 95). The overall incidence of dental caries was 46.6%. The greatest incidence of dental caries was found in the group of children with previous caries experience (61.1%). Among the children without dental caries in the first exam, 36.7% exhibited caries in the second exam. The majority of children (72.6%) received no treatment for carious lesions in the two-year interval between examinations. Children with previous dental caries (RR: 1.52, 95%CI: 1.12-2.05) had a greater risk of developing new lesions, compared with the children without previous dental caries. The incidence of dental caries was high and most of children's caries were untreated. Previous caries experience is a risk factor for developing new carious lesions in children.

  20. Clinical follow-up of ceramic bridges with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiang-hao; SUN Feng

    2009-01-01

    Background Alternatives to the conventional auro-galvanoforming ceramic bridge need to be evaluated in long-term longitudinal studies before being recommended for restoration of dentition defects. This study aimed to evaluate the clinical performance of a ceramic bridge with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects.Methods In total, 114 ceramic bridges with auro-galvanoforming (primary coping and Ni-Cr pontic) were placed in 112 patients with dentition defects. Among them, 83 bridges in 82 patients were available for follow-up after 7 years. We evaluated marginal integrity, color match, gingival inflammation, fracture of ceramic bridges, and recurrent caries. Results Marginal integrity of the ceramic bridges was perfect in all patients. Most ceramic bridges maintained their original color. Fracture was found in three bridges; the rest were free of fracture, breakage, and loosening. Recurrent abutment caries were not found. Ceramic bridges with auro-galvanoforming (primary coping and Ni-Cr pontic) produced satisfactory clinical outcomes-equivalent to the conventional porcelain-fused-to-metal restoration. This technique is especially useful for dentition defects of the molar area and is cheaper than restoration with noble metal bridges. Conclusions Ceramic bridges with auro-galvanoforming (primary coping and Ni-Cr pontic) performed well for the restoration of dentition defects during this follow-up period. More studies are warranted to further evaluate this technique as an alternative to the conventional porcelain-fused-to-metal restoration.

  1. Adopted and Permanently Placed Children in Education: From Rainbows to Reality

    Science.gov (United States)

    Gore Langton, Emma

    2017-01-01

    Children who leave care into adoption and special guardianship are often considered by schools and local authorities to have found their "happy ending." Yet there is growing evidence that the impact of prenatal and early trauma, abuse and neglect does not disappear upon placement in a permanent family. Rates of social, emotional and…

  2. Permanent Magnet Eddy Current Loss Analysis of a Novel Motor Integrated Permanent Magnet Gear

    DEFF Research Database (Denmark)

    Zhang, Yuqiu; Lu, Kaiyuan; Ye, Yunyue

    2012-01-01

    In this paper, a new motor integrated permanent magnet gear (MIPMG) is discussed. The focus is on eddy current loss analysis associated to permanent magnets (PMs). A convenient model of MIPMG is provided based on 2-D field-motion coupled time-stepping finite element method for transient eddy...

  3. 31 CFR 515.335 - Permanent resident alien.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Permanent resident alien. 515.335... Definitions § 515.335 Permanent resident alien. As used in § 515.208, the term permanent resident alien means an alien lawfully admitted for permanent residence into the United States. ...

  4. Permanence and global attractivity for Lotka-Volterra difference systems.

    Science.gov (United States)

    Lu, Z; Wang, W

    1999-09-01

    The permanence and global attractivity for two-species difference systems of Lotka-Volterra type are considered. It is proved that a cooperative system cannot be permanent. For a permanent competitive system, the explicit expression of the permanent set E is obtained and sufficient conditions are given to guarantee the global attractivity of the positive equilibrium of the system.

  5. Bone loss at implants and teeth in the same segment of the dentition in partially dentate subjects.

    Science.gov (United States)

    Cecchinato, Denis; Marino, Massimiliano; Lindhe, Jan

    2017-05-01

    Some studies have indicated that marginal bone loss at implants and at teeth are similar, while results from other studies showed that implants lost more bone than teeth in the same dentition. To determine the amount of progressive marginal bone loss that had occurred at implants and teeth in the same segment of the dentition following implant placement in partially dentate subjects. A total of 217 patients with a total of 573 implants and 318 teeth present in the same segments of the dentition were included. Radiographs were available from 1 year (baseline) and ≥3 years after loading. The mean bone loss that occurred between the two examinations was at implants 0.42 ± 0.68 mm and at teeth 0.44 ± 0.52 mm. Thirty-eight subjects (18%) had ≥1 implant exhibiting >1 mm bone loss. Bone loss at the 148 implants in this category of patients was 1.30 ± 1.04 mm with a corresponding loss at the 69 teeth of 0.53 ± 0.62 mm. Eighteen subjects (8%) had ≥1 tooth that exhibited >1 mm bone loss. The mean amount of bone loss in this sample was 1.37 ± 0.87 mm (38 teeth) and 0.29 ± 0.31 mm (56 implants). This study showed that marginal bone loss at implants and teeth in many partially dentate subjects might be independent phenomena. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Self reported behavioral and emotional difficulties in relation to dentition status among school going children of Dilsukhnagar, Hyderabad, India

    Directory of Open Access Journals (Sweden)

    Adepu Srilatha

    2016-01-01

    Full Text Available Background: Oral health has strong biological, psychological, and social projections, which influence the quality of life. Thus, developing a common vision and a comprehensive approach to address children′s social, emotional, and behavioral health needs is an integral part of the child and adolescent′s overall health. Aim: To assess and compare the behavior and emotional difficulties among 15-year-olds and to correlate it with their dentition status based on gender. Study Settings and Design: A cross-sectional questionnaire study among 15-year-old schoolgoing children in six private schools in Dilsukhnagar, Hyderabad, India. Materials and Methods: The behavior and emotional difficulties were assessed using self-reported Strengths and Difficulties Questionnaire (SDQ. The dentition status was recorded by the criteria given by the World Health Organization (WHO in the Basic Oral Health Survey Assessment Form (1997. Statistical Analysis: Independent Student′s t-test was used for comparison among the variables. Correlation between scales of SDQ and dentition status was done using Karl Pearson′s correlation coefficient method. Results: Girls reported more emotional problems and good prosocial behavior and males had more conduct problems, hyperactivity, peer problems, and total difficulty problems. Total decayed-missing-filled teeth (DMFT and decayed component were significantly and positively correlated with total difficulty, emotional symptom, and conduct problems scale while missing component was correlated with the hyperactivity scale and filled component with prosocial behavior. Conclusion: DMFT and its components showed an association with all scales of SDQ except for peer problem scale. Thus, the oral health of children was significantly influenced by behavioral and emotional difficulties; so, changes in the mental health status will affect the oral health of children.

  7. Distalization of the maxillary and mandibular dentitions with miniscrew anchorage in a patient with moderate Class I bimaxillary dentoalveolar protrusion.

    Science.gov (United States)

    Chen, Gui; Teng, Fei; Xu, Tian-Min

    2016-03-01

    This case report describes the treatment of a 25-year-old woman with a skeletal Class I pattern and moderate bimaxillary dentoalveolar protrusion. The orthodontic treatment included distal movement of her maxillary and mandibular dentitions using 1-stage miniscrews. The total active treatment time was about 12 months. Her tooth alignment and profile were significantly improved by the orthodontic treatment. The 2-year posttreatment records show a stable occlusion and satisfactory facial esthetics. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  8. Allometric relationships of the dentition of the great White Shark, Carcharodon carcharias, in forensic investigations of shark attacks

    OpenAIRE

    Nambiar, P.; Bridges, T. E.; K. A. Brown

    1991-01-01

    As a result of a systematic morphometric study of shark dentitions, a system of notation for describing the location of shark teeth has been developed and is proposed as a standard to be adopted for use in similar studies in the future. The macroscopic morphology of White Shark teeth has been characterised in order to gain quantitative data which might assist in identification of these sharks from bite marks on victims or objects or from shark carcasses. Using these data, a nomogram has been ...

  9. Identification of Transient and Permanent Faults

    Institute of Scientific and Technical Information of China (English)

    李幼仪; 董新洲; 孙元章

    2003-01-01

    A new algorithm was developed for arcing fault detection based on high-frequency current transients analyzed with wavelet transforms to avoid automatic reclosing on permanent faults. The characteristics of arc currents during transient faults were investigated. The current curves of transient and permanent faults are quite similar since current variation from the fault arc is much less than the voltage variation. However, the fault current details are quite different because of the arc extinguishing and reigniting. Dyadic wavelet transforms were used to identify the current variation since wavelet transform has time-frequency localization ability. Many electric magnetic transient program (EMTP) simulations have verified the feasibility of the algorithm.

  10. Permanent isolation surface barrier: Functional performance

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1993-10-01

    This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release.

  11. Design and construction of permanent magnetic gears

    OpenAIRE

    Jørgensen, Frank Thorleif

    2010-01-01

    This thesis deals with design and development of permanent magnetic gears. The goal of this thesis is to develop knowledge and calculation software for magnetic gears. They use strong NdFeB permanent magnets and a new magnetic gear technology, which will be a serious alternative to classical mechanical gears. The new magnetic gear will have a high torque density1 relationship –high efficiency and are maintenance free. In this project was manufactured two test gears which is tested and verifie...

  12. A clinical observation on interocclusal labial arch appliance treatment of functional crossbite of transitional dentition%颌间唇弓式活动矫正器治疗替牙期反牙合的临床研究

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    目的介绍一种临床上行之有效的治疗替牙期功能性反牙合的矫治方法。方法选择25例替牙期反牙合的患者。男18例,女7例,平均年龄10.5岁。均为替牙期功能性反牙合,X线头影测量显示部分病例为轻度下颌前突。结果平均疗程为1个月,SNB、ANB、LI-MP经统计学处理有显著性差异。结论颌间唇弓式矫治器治疗儿童早期功能性反牙合效果肯定。与其他矫治器比较,具有结构简单,疗程短的优点。%Objective To introduce an effective clinical appliance for functional crossbite of transitional dentition.Methods Twenty-Five cases of functional crossbite of transtional dentition,18 male cases and 7 female cases.The average age was 10.5 years.X-ray cephalometry showed some cases with light mandibular prognathism.Results Average course of treatment is one month,SNB,ANB and LI-MP showed significant statistical differences.Conclusion Interocclusal labial arch appliance is an effective method for treatment of children's functional crossbite in early stage.It has simpler structure and shorter course of treatment comparing with other appliance.

  13. Application of dynamic elect roneuro-stimulation at treatment of patients with deformations of dentitions complicated by muscular and articular dysfunction

    Directory of Open Access Journals (Sweden)

    Konnov V.V.

    2013-09-01

    Full Text Available The purpose: to evaluate the efficacy of dynamic electroneurostimulation in the complex treatment of patients with strains of dentition complicated by muscular and articular dysfunction. Material and methods. A total of 38 patients aged 25 to 49 years with the strains of dentition, complicated by muscular and articular dysfunction. Clinical, radiological and graphical methods have been applied. In the combined treatment of dentition deformities complicated by muscular and articular dysfunction, to relieve pain the method of dynamic electroneurostimulation has been used. Results help provide the information about the features and effectiveness of dynamic dysfunction. Conclusion. The use of dynamic electroneurostimulation relieves pain in various degrees of dysfunction in this case, restoring the function of the masticatory muscles and temporomandibular joint. Combining the frequency increases the therapeutic effect of the method by reducing the time of onset of analgesia and extending the duration of its action.

  14. Comparison of Radiography, Laser Fluorescence and Visual Examination for Diagnosing Incipient Occlusal Caries of Permanent First Molars

    OpenAIRE

    Bahrololoomi, Zahra; Ezoddini, Fateme; Halvani, Niloofar

    2015-01-01

    Objectives: Early diagnosis of incipient and non-cavitated carious lesions is crucial for performing preventive treatments. The aim of this study was to compare the efficacy of three diagnostic methods of bitewing radiography, DIAGNOdent, and visual examination in diagnosing incipient occlusal caries of permanent first molars. Materials and Methods: In this diagnostic cross-sectional study, 109 permanent first molar teeth of 31 patients aged 7–13 years were examined visually, on bitewing radi...

  15. Prediction and analysis of magnetic forces in permanent magnet brushless dc motor with rotor eccentricity

    Science.gov (United States)

    Liu, Z. J.; Li, J. T.; Jabbar, M. A.

    2006-04-01

    In design of permanent magnet motors for high-precision applications, it is sometimes necessary, early in the design stage, to have a detailed analysis of the effect of rotor eccentricity that may result from manufacturing imperfectness or use of fluid dynamic or aerodynamic bearings. This paper presents an analytical model for electromagnetic torque and forces in permanent magnet motors with rotor eccentricity. The model gives an insight to the relationship between the effect of the eccentricity and the other motor design parameters on the electromagnetic forces. It is shown that the calculated magnetic forces obtained from this model agree well with those obtained from numerical simulations that are very computationally demanding.

  16. PROCEDURE FOR ESTIMATING PERMANENT TOTAL ENCLOSURE COSTS

    Science.gov (United States)

    The paper discusses a procedure for estimating permanent total enclosure (PTE) costs. (NOTE: Industries that use add-on control devices must adequately capture emissions before delivering them to the control device. One way to capture emissions is to use PTEs, enclosures that mee...

  17. SNO expanded and given permanent status

    CERN Multimedia

    2003-01-01

    The Sudbury Neutrino Observatory (SNO) is being transformed into a permanent international research facility with the assistance of the Canada Foundation for Innovation's International Access Fund. The CFI is providing $38.9 million to establish the new International Facility for Underground Science (1/2 page).

  18. Lowering the Permanent Rate of Unemployment.

    Science.gov (United States)

    Feldstein, Martin S.

    The first section of the study on lowering the permanent rate of unemployment discusses the effects and limitations of increasing aggregate demand through fiscal and monetary policy and indicates the inability to achieve the desired level of unemployment simply by stimulating demand. Section 2 analyzes the characteristics and structure of our…

  19. Permanent magnet motor technology design and applications

    CERN Document Server

    Gieras, Jacek F

    2009-01-01

    Demonstrates the construction of permanent magnet (PM) motor drives and supplies ready-to-implement solutions to common roadblocks along the way. This book also supplies fundamental equations and calculations for determining and evaluating system performance, efficiency, reliability, and cost. It explores modern computer-aided design of PM motors.

  20. Dovetail spoke internal permanent magnet machine

    Science.gov (United States)

    Alexander, James Pellegrino; EL-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Shah, Manoj Ramprasad; VanDam, Jeremy Daniel

    2011-08-23

    An internal permanent magnet (IPM) machine is provided. The IPM machine includes a stator assembly and a stator core. The stator core also includes multiple stator teeth. The stator assembly is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface defining a cavity. The IPM machine also includes a rotor assembly and a rotor core. The rotor core is disposed inside the cavity and configured to rotate about the longitudinal axis. The rotor assembly further includes a shaft. The shaft further includes multiple protrusions alternately arranged relative to multiple bottom structures provided on the shaft. The rotor assembly also includes multiple stacks of laminations disposed on the protrusions and dovetailed circumferentially around the shaft. The rotor assembly further includes multiple pair of permanent magnets for generating a magnetic field, which magnetic field interacts with the stator magnetic field to produce a torque. The multiple pair of permanent magnets are disposed between the stacks. The rotor assembly also includes multiple middle wedges mounted between each pair of the multiple permanent magnets.

  1. Permanent downhole seismic sensors in flowing wells

    NARCIS (Netherlands)

    Jaques, P.; Ong, H.; Jupe, A.; Brown, I.; Jansenns, M.

    2003-01-01

    It is generally accepted that the 'Oilfield of the Future' will incorporate distributed permanent downhole seismic sensors in flowing wells. However the effectiveness of these sensors will be limited by the extent to which seismic signals can be discriminated, or de-coupled, from flow induced

  2. Permanent female mimics in a lekking shorebird

    NARCIS (Netherlands)

    Jukema, Joop; Piersma, Theunis

    2006-01-01

    Female mimics are known from many species, but permanent, non-conditional, alternative mating strategies are only known from an isopod, a fish, a lizard and a bird. The single bird example refers to lek-breeding ruffs Philomachus pugnax, a shorebird for which two strategies (independent and satellit

  3. Diferencias sexuales en la dentición temporal Sex differences in primary dentition

    Directory of Open Access Journals (Sweden)

    Rosalina Sánchez Torres

    2004-08-01

    Full Text Available Se estudia una muestra de 165 niños de 5 años de ambos sexos conformada a partir de un universo de 568 alumnos de 21 grupos de preescolar del municipio de Santa Clara. Se seleccionaron los que presentaron dentición temporal completa. A todos se les realizó un estudio de la oclusión, incluyendo aspectos morfológicos y funcionales, con el objetivo de comparar su comportamiento en ambos sexos. Se utilizó la técnica de CHAID para detectar cuáles son las variables que más se distinguen por sexo y las otras variables que puedan interactuar con estas. Entre las morfológicas se encontró una sola que se distingue: La medición de Bogué, y las funcionales que más se distinguen se pueden resumir como: hábito de succión, interferencias en lateralidad desde distintos puntos de vista, y lateralidad máxima. De esta manera se logra predecir, según el CHAID, las características oclusales más probables en cada sexo.A sample of 165 five-years-old children of both sexes, taken from a universe of 568 children making up 21 kindergarten groups in Santa Clara municipality, was studied. Those children who presented with their complete primary dentition were selected. An occlusion study including morphological and functional aspects was performed to compare occlusion in both sexes using CHAID techniques to detect the most outstanding variables by sex and the other variables that may interact with the former. The only noticeable morphological variable was Bogue´s measurement whereas the most evident functional variables were sucking habits, interference in laterality from several viewpoints and maximum laterality. In this way, it is possible to predict the most likely occlusal characteristics by sex according to the CHAID technique.

  4. Permanent isolation surface barrier development plan

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

  5. Gingival Zenith Positions and Levels of Maxillary Anterior Dentition in Cases of Bimaxillary Protrusion: A Morphometric Analysis.

    Science.gov (United States)

    Gowd, Snigdha; Shankar, T; Chatterjee, Suravi; Mohanty, Pritam; Sahoo, Nivedita; Baratam, Srinivas

    2017-08-01

    To investigate the two clinical parameters, such as gingival zenith positions (GZPs) and gingival zenith levels (GZLs), of maxillary anterior dentition in bimaxillary protrusion cases and collate it with severiety of crown inclination. Gingival zenith position and GZL in 40 healthy patients (29 females and 11 males) with an average age of 21.5 years were assessed. Inclusion criteria involved absence of periodontal diseases, Angle's class I molar relationship, and upper anterior proclination within 25 to 45° based on Steiner's analysis; exclusion criteria included spacing, crowding, anterior restoration and teeth with incisor attrition or rotation. The GZP was evaluated using digital calipers from voxel-based morphometry (VBM), and GZL was assessed from the tangent drawn from GZP of central incisor and canines to the linear vertical distance of GZP of lateral incisor. All the central incisors showed a GZP distal to VBM with a mean average of 1 mm. Severe proclination between 40 and 45° showed a statistically significant variation. Lateral incisors displayed a mean of 0.5 mm deviation of GZP from the vertically bisected midline. In 80% of canine population, GZP was centralized. We conclude that the degree of proclination of maxillary anterior dentition was correlated to the gingival contour in bimaxillary cases. The investigation revealed that there is a variation in the location of GZP as the severity of proclination increases. This study highlights the importance of microesthetics in fixed orthodontic treatment. The gingival contour should be unaltered while retraction during management of bimaxillary protrusion.

  6. Advancements in all-ceramics for dental restorations and their effect on the wear of opposing dentition

    Science.gov (United States)

    Rashid, Haroon; Sheikh, Zeeshan; Misbahuddin, Syed; Kazmi, Murtaza Raza; Qureshi, Sameer; Uddin, Muhammad Zuhaib

    2016-01-01

    Tooth wear is a process that is usually a result of tooth to tooth and/or tooth and restoration contact. The process of wear essentially becomes accelerated by the introduction of restorations inside the oral cavity, especially in case of opposing ceramic restorations. The newest materials have vastly contributed toward the interest in esthetic dental restorations and have been extensively studied in laboratories. However, despite the recent technological advancements, there has not been a valid in vivo method of evaluation involving clinical wear caused due to ceramics upon restored teeth and natural dentition. The aim of this paper is to review the latest advancements in all-ceramic materials, and their effect on the wear of opposing dentition. The descriptive review has been written after a thorough MEDLINE/PubMed search by the authors. It is imperative that clinicians are aware of recent advancements and that they should always consider the type of ceramic restorative materials used to maintain a stable occlusal relation. The ceramic restorations should be adequately finished and polished after the chair-side adjustment process of occlusal surfaces. PMID:28042280

  7. Advancements in all-ceramics for dental restorations and their effect on the wear of opposing dentition.

    Science.gov (United States)

    Rashid, Haroon; Sheikh, Zeeshan; Misbahuddin, Syed; Kazmi, Murtaza Raza; Qureshi, Sameer; Uddin, Muhammad Zuhaib

    2016-01-01

    Tooth wear is a process that is usually a result of tooth to tooth and/or tooth and restoration contact. The process of wear essentially becomes accelerated by the introduction of restorations inside the oral cavity, especially in case of opposing ceramic restorations. The newest materials have vastly contributed toward the interest in esthetic dental restorations and have been extensively studied in laboratories. However, despite the recent technological advancements, there has not been a valid in vivo method of evaluation involving clinical wear caused due to ceramics upon restored teeth and natural dentition. The aim of this paper is to review the latest advancements in all-ceramic materials, and their effect on the wear of opposing dentition. The descriptive review has been written after a thorough MEDLINE/PubMed search by the authors. It is imperative that clinicians are aware of recent advancements and that they should always consider the type of ceramic restorative materials used to maintain a stable occlusal relation. The ceramic restorations should be adequately finished and polished after the chair-side adjustment process of occlusal surfaces.

  8. Management of developing skeletal class III malocclusion in a prepubertal girl with prognathic mandible in late mixed dentition

    Directory of Open Access Journals (Sweden)

    Satinder Pal Singh

    2017-01-01

    Full Text Available Treatment of skeletal Class III patients at younger age is highly unpredictable. The patient may respond well to the treatment or may show excessive mandibular growth during growth spurt which may require orthognathic surgery later on. If not treated at earlier stages of life, the condition may worsen with time. This case report will present the comprehensive orthodontic management of a 9-year-old prepubertal girl in late mixed dentition with prognathic mandible. Chin cup therapy was started and continued for 3 years. After chin cup therapy, maxillary and mandibular dentition were bonded with standard edgewise appliance. After leveling and alignment, Class III elastics were started. Fixed orthodontic treatment was completed in 3 years. At the end, good Class I molar and canine relationship with normal overjet and overbite were achieved. The total treatment time of orthopedic and orthodontic correction was 6 years, 2 months. The patient revealed the same Class I molar and canine relationship after 6 years of treatment. Redirection of mandibular growth pattern from hyperdivergent to normodivergent advocates the use of chin cup as a viable treatment regimen for the management of prognathic mandible in prepubertal patients.

  9. Changes on facial profile in the mixed dentition, from natural growth and induced by Balters' bionator appliance

    Directory of Open Access Journals (Sweden)

    Denise Rocha Goes Landázuri

    2013-04-01

    Full Text Available OBJECTIVE: The purpose of this study was to evaluate the facial profile changes induced by Balters' bionator appliance in Class II division 1 patients, at mixed dentition stage. METHODS: The sample consisted of 28 prepubertal individuals at stages 1 and 2 of skeletal maturation (CVM, which were divided in two groups. The experimental group consisted of 14 individuals (7 boys and 7 girls, initial mean age of 8y12m which were treated with Balters' bionator appliance for 14.7 months. The effects of treatment were compared to a control group of 14 subjects (7 boys and 7 girls, initial mean age of 8y5m with Class II malocclusion, division 1, not orthodontically treated, which were followed up for 15.4 months. The statistical analysis was performed using Student's t test, at a significance level of 5%. RESULTS: The results showed that the Balters' bionator appliance promoted a significant increase on the mentolabial angle, in addition to demonstrating a tendency to reduce the facial skeletal convexity, to restrict the maxillary growth and to increase the nasolabial angle and the lower anterior facial height. CONCLUSION: It can be concluded that the Balters' bionator appliance improved the facial profile of children treated at mixed dentition stage.

  10. A basis of settlement: Economic foundations of permanent pioneer communities

    Science.gov (United States)

    Jones, Eric M.

    1992-01-01

    High transport costs will dominate the course of lunar development. During the earliest phases, when lunar facilities consist of a research and resource development complex with staff serving tours of a few months, transport costs will encourage local production of fuel, food, and building materials. Once these capabilities are in place and the number of personnel grows to a few hundred, staff rotation might well dominate transport budgets. At that point it would make economic sense to encourage some members of staff to become permanent residents. By analogy with early British settlement in Australia, a vigorous private sector economy could emerge if the lunar organization provided quasi-export earnings through its role as the community's major employer and as the major buyer of locally produced goods. By providing such a market for goods and services, the lunar organization would not only provide a means whereby permanent residents could support themselves, but could also accelerate the process of replacing imported goods with local manufacturers, thereby reducing the cost of operations. By analogy with recent Alaskan experience, if the resource development activity started making money from sales to orbital customers, export taxes and/or royalty payments could also provide means by which a lunar community could support itself.

  11. Efficient IEC permanent magnet motor; Effizienter IEC Permanent-Magnetmotor (3 kW) - Jahresbericht 2007

    Energy Technology Data Exchange (ETDEWEB)

    Lindegger, M.; Salathe, D.; Biner, H. P.; Evequoz, B.

    2007-07-01

    This annual report for the Swiss Federal Office of Energy (SFOE) takes a look at the work done at the Swiss Universities of Applied Sciences in Lucerne and Valais and the Circle Motor Company in 2007 on the economic feasibility, efficiency and limitations of permanent magnet motors. The higher efficiency of permanent-magnet motors in comparison with asynchronous motors for powers of over 100 kW is noted. Work done on the integration of a 3 kW permanent-magnet motor in an IEC-Standard housing is described. The construction of an efficient permanent magnet motor drive and its testing at the Valais University of Applied Sciences is discussed. The high efficiencies obtained both for the motor and its drive electronics are noted.

  12. Aspiration of two permanent teeth during maxillofacial injuries.

    Science.gov (United States)

    Xiao, Wen-lin; Zhang, Dai-zun; Wang, Yan-hui

    2009-03-01

    Aspiration of a tooth in maxillofacial injuries is a known complication necessitating prompt recognition and early treatment to minimize potentially serious and, sometimes, even fatal consequences. Here, we report a rare and unusual case in its presentation, the patient having aspirated 2 permanent teeth after maxillofacial, cervical vertebrae, and thoracic region crush injuries due to a motor vehicle accident. The diagnosis of teeth aspiration was delayed until 2 weeks after the event. An aspirated anterior tooth was expectorated by the patient himself, and the other aspirated anterior tooth was removed by flexible bronchoscopy. The paper also emphasizes that clinicians must be aware of dental injury resulting from maxillofacial injuries and account for all teeth as part of their evaluation, keeping an open mind as to where a missing tooth might be located. A rapid diagnosis depends on high clinical suspicion, clinical signs, and radiologic findings.

  13. Hybrid high gradient permanent magnet quadrupole

    Science.gov (United States)

    N'gotta, P.; Le Bec, G.; Chavanne, J.

    2016-12-01

    This paper presents an innovative compact permanent magnet quadrupole with a strong gradient for potential use in future light source lattices. Its magnetic structure includes simple mechanical parts, rectangular permanent magnet blocks and soft iron poles. It has a wide aperture in the horizontal plane to accommodate an x-ray beam port, a common constraint in storage ring-based light sources. This specificity introduces field quality deterioration because of the resulting truncation of the poles; a suitable field quality can be restored with an optimized pole shape. A 82 T /m prototype with a bore radius of 12 mm and a 10 mm vertical gap between poles has been constructed and magnetically characterized. Gradient inhomogeneities better than 10-3 in the good field region were obtained after the installation of special shims.

  14. Design and construction of permanent magnetic gears

    DEFF Research Database (Denmark)

    Jørgensen, Frank Thorleif

    This thesis deals with design and development of permanent magnetic gears. The goal of this thesis is to develop knowledge and calculation software for magnetic gears. They use strong NdFeB permanent magnets and a new magnetic gear technology, which will be a serious alternative to classical...... calculation models for determination of gear output torque from different magnetic gear types are analysed. These analytical calculations models are used together with optimisation tools in order to improve the performance of investigated magnetic gear types. Experimental test gears are designed to validate...... is searched and only a single reference [74] is found and that is why the combination of a cycloidal gear and a magnetic gear are considered as an innovative supplement to magnetic gear technology. A magnetic cycloidal gear is designed with a gearing of 1:21 and a calculated active torque density of 142 [Nm...

  15. Permanence and Community Structure in Complex Networks

    CERN Document Server

    Chakraborty, Tanmoy; Ganguly, Niloy; Mukherjee, Animesh; Bhowmick, Sanjukta

    2016-01-01

    The goal of community detection algorithms is to identify densely-connected units within large networks. An implicit assumption is that all the constituent nodes belong equally to their associated community. However, some nodes are more important in the community than others. To date, efforts have been primarily driven to identify communities as a whole, rather than understanding to what extent an individual node belongs to its community. Therefore, most metrics for evaluating communities, for example modularity, are global. These metrics produce a score for each community, not for each individual node. In this paper, we argue that the belongingness of nodes in a community is not uniform. The central idea of permanence is based on the observation that the strength of membership of a vertex to a community depends upon two factors: (i) the the extent of connections of the vertex within its community versus outside its community, and (ii) how tightly the vertex is connected internally. We discuss how permanence ...

  16. Sensorless Control of Permanent Magnet Synchronous Machines

    DEFF Research Database (Denmark)

    Matzen, Torben N.

    Permanent magnet machines, with either surface mounted or embedded magnets on the rotor, are becoming more common due to the key advantages of higher energy conversion efficiency and higher torque density compared to the classical induction machine. Besides energy efficiency the permanent magnet...... are dependent on the phase currents and rotor position. Based on the flux linkages the differential inductances are determined and used to establish the inductance saliency in terms of ratio and orientation. The orientation and its dependence on the current and rotor position are used to analyse the behaviour...... and establish the suitability of the machine for sensorless control using inductance saliency tracking methods. The same electromagnetic behaviour is used in the implementation of a dynamical simulation model of the machine useful for evaluation of sensorless control methods at the control design stage. Further...

  17. Design of permanent magnetic solenoids for REGAE

    Energy Technology Data Exchange (ETDEWEB)

    Gehrke, Tim; Zeitler, Benno; Gruener, Florian [University of Hamburg and Center for Free-Electron Laser Science, Hamburg (Germany); Floettmann, Klaus [DESY, Hamburg (Germany); Manz, Stephanie [MPSD, University of Hamburg (Germany)

    2013-07-01

    The Relativistic Electron Gun for Atomic Exploration REGAE is a small linear accelerator at DESY in Hamburg, which produces short, low emittance electron bunches. Two future experiments at REGAE, an external injection experiment for Laser Wakefield Acceleration (LWA) and a time resolving Transmission Electron Microscopy (TEM) setup, require strong focusing magnets inside the target chamber. Permanent magnetic solenoids can provide the needed focusing strength due to their enormous surface current density, while having compact dimensions at the same time. Solenoids are fundamentally non-linear focusing elements whose non-linearity is worst for short, strong magnets as required for REGAE. The induced emittance growth is investigated and minimized for different setups with axially and radially magnetized annular magnets. Since permanent magnetic solenoids cannot be switched off but are not needed in every experiment at REGAE, a mechanical lifting-system and a magnetic shielding has to ensure, that the different experiments do not disturb each other.

  18. Robotized Surface Mounting of Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Erik Hultman

    2014-10-01

    Full Text Available Using permanent magnets on a rotor can both simplify the design and increase the efficiency of electric machines compared to using electromagnets. A drawback, however, is the lack of existing automated assembly methods for large machines. This paper presents and motivates a method for robotized surface mounting of permanent magnets on electric machine rotors. The translator of the Uppsala University Wave Energy Converter generator is used as an example of a rotor. The robot cell layout, equipment design and assembly process are presented and validated through computer simulations and experiments with prototype equipment. A comparison with manual assembly indicates substantial cost savings and an improved work environment. By using the flexibility of industrial robots and a scalable equipment design, it is possible for this assembly method to be adjusted for other rotor geometries and sizes. Finally, there is a discussion on the work that remains to be done on improving and integrating the robot cell into a production line.

  19. Secondary cicatricial and other permanent alopecias.

    Science.gov (United States)

    Finner, Andreas M; Otberg, Nina; Shapiro, Jerry

    2008-01-01

    Various nonfollicular scalp conditions can cause secondary scarring or permanent alopecia. Possible causes are congenital defects, trauma, inflammatory conditions, infections, and neoplasms (rarely drugs). Associated signs and symptoms and other diagnostic procedures such as histopathology may aid in the diagnosis. Detection of the underlying disorder may be difficult in end-stage lesions. Treatment is specific for active conditions. Surgery and hair transplantation are options for localized scars.

  20. A Novel Permanent Magnetic Angular Acceleration Sensor

    OpenAIRE

    Hao Zhao; Hao Feng

    2015-01-01

    Angular acceleration is an important parameter for status monitoring and fault diagnosis of rotary machinery. Therefore, we developed a novel permanent magnetic angular acceleration sensor, which is without rotation angle limitations and could directly measure the instantaneous angular acceleration of the rotating system. The sensor rotor only needs to be coaxially connected with the rotating system, which enables convenient sensor installation. For the cup structure of the sensor rotor, it h...