Non-syndromic supernumerary teeth: report of a case with 6 supernumerary teeth

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Taghibakhsh M

2011-02-01

Full Text Available "nBackground and Aims: Multiple supernumerary teeth are rare and often found in association with syndromes such as Gardner, Cleidocranial dysplasia and cleft lip and palate, with a much less chance for isolated"nnon-syndromic cases. The aim of this study was to report a case with 6 supernumerary teeth without syndromic association."nCase Report: The patient was a 33 year-old female, referred to oral diseases and diagnosis department with chief complaint of sensitivity to cold and hot food in right upper premolar region. Oral examination revealed 5 erupted lingually supernumerary teeth (four in mandibular and one in maxillary premolar region, respectively. Further panoramic radiography clarified an extra impacted tooth in the palatal region of left premolar maxillary area. All extra teeth had been appeared since the age of 17 during one year, as the patient claimed. Medical history and thorough clinical and paraclinical examinations were not significant except for the hypothyroidism, since 5 years ago. No other family member noticed to be the case. Based on our findings, a diagnosis of non-syndromic multiple supernumerary teeth was established."nConclusion: A thorough examination of each patient presented with supernumerary teeth, including panoramic and intraoral radiographic images may provide valuable information regarding accompanying syndromes and unerupted teeth. Early diagnosis is an essential step for orthodontic or surgical decisions making, preventing or avoiding worsening complications such as malocclusion, adjacent normal teeth delayed eruption or rotation, diasthema, cystic lesions and resorption of contiguous teeth.

A Diagnostic and Therapeutic Algorithm for Impacted Teeth for Plastic Surgeons: Outcomes of 242 Extracted Teeth

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Nebil Yeşiloğlu

2016-09-01

Full Text Available Objective: Impacted teeth are important for plastic surgeons that frequently perform maxillofacial operations because of their tendency to affect dental occlusion, and thus, cephalometric results. Moreover, severe complications are also caused by the tooth and its surgical removal. In this study, retrospective analysis of 242 extracted teeth and 24 extracted roots was performed and an algorithmic approach to different types and the localizations of impacted teeth was presented. Possible complications and salvage procedures were also discussed. Material and Methods: A retrospective analysis of 128 patients who underwent impacted teeth removal surgery between 2013 and 2015 was performed. Mean age was 26 years (Range: 18–42 years, and the female to male ratio was 39/89. Sixteen of the patients were operated under regional nerve block, whereas the remaining were operated under general anesthesia. In 107 patients, the whole tooth was removed, whereas the residual root of the tooth was removed in 21 patients. In 89 patients, bone interventions like the creation of bone window or peridental milling to loosen the tooth were needed, whereas only oral mucosal incisions were performed in the remaining patients. Results: The most common onset symptom was localized pain, and the most common complications were swelling and edema. The most common extracted tooth was the mandibular 3rd molar. Lower lip hypoesthesia, which was continued up to eight months, was encountered in six patients who underwent mandibular 3rd molar extraction. Conclusion: In our opinion, a wide range of possible complications secondary to impacted teeth surgery makes them important for plastic surgeons who are more experienced than other disciplines, and learning teeth extraction is essential to learn in plastic surgery specialty training.

Supernumerary teeth in non-syndromic patients

International Nuclear Information System (INIS)

Mali, Santosh; Karjodkar, Freny Rashmiraj; Sontakke, Subodh; Sansare, Kaustubh

2012-01-01

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.

INVESTIGATION OF IMPACTED SUPERNUMERARY TEETH: A CONE BEAM COMPUTED TOMOGRAPH (CBCT STUDY

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Gökhan GÜRLER

2017-10-01

Full Text Available Purpose: The purpose of this study was to investigate the impacted supernumerary teeth which were initially detected on panoramic radiographs by using cone beam computed tomography (CBCT. Materials and Methods: In this retrospective study, supernumerary teeth diagnosed on panoramic radiographs taken from patients who had admitted for routine dental treatment were evaluated using CBCT. Patients’ age, gender, systemic conditions as well as number of supernumerary teeth, unilateral-bilateral presence, anatomical localization (maxilla, mandible, anterior-premolar-molar, mesiodens-lateral-canine, parapremolar-paramolar-distomolar shape (rudimentary, supplemental, tuberculate, odontoma, position (palatal-lingual-buccal-labial-central, shortest distance between the tooth and adjacent cortical plate, complications and treatment were assessed. Results: A total of 47 impacted supernumerary teeth in 34 patients were investigated in this study. Of these, 33 (70.2% were unilateral and 14 (29.8% were bilateral. Only 1 supernumerary tooth was found in 27 patients (79.4% whereas 7 patients (20.6% had 2 or more supernumerary teeth. Most of the teeth located in the anterior region (74.4% of the jaws and maxilla (74.4%. Twenty teeth (42.5% were mesiodens, 11 (23.4% were lateral or canine, 14 (29.7% were parapremolar and 2(4.4% were distomolar. Twenty-seven teeth (57.4% were rudimentary, 15 (31.9% were supplemental and 5 (10.7% were odontoma in shape. The shortest distance between the supernumerary tooth and adjacent cortical plate varied between 0 to 2.5 mm with a mean of 0.66 mm. The most common clinical complaint was the non-eruption of permanent teeth (42.5%. All supernumerary teeth were removed under local anesthesia. Orthodontic traction was performed for those impacted permanent teeth if necessary. Conclusion: Impacted supernumerary teeth are usually in close proximity to cortical bone. Although this may facilitate surgical access, there is a risk of

Interdisciplinary treatment of a patient with multiple missing teeth and periodontitis.

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Ahn, Jae-Chan; Lee, Jae-Hong; Yoon, Joon-Ho; Lee, Ji-Yeon; Kim, Jung-Hoon

2018-02-01

A 49-year-old woman with several missing and periodontically compromised teeth was referred to the orthodontic department of National Health Insurance Service Ilsan Hospital by the periodontic department for interdisciplinary treatment. Multiple posterior teeth had been extracted 10 days earlier. Her chief complaint was crowding of the anterior teeth, and she wanted to improve both esthetics and function. Orthodontic, periodontic, and prosthodontic treatments were undertaken in the proper timing and sequence with an interdisciplinary approach. As a result, improved periodontal health and a stable occlusion and vertical dimension were achieved. Although there were limited teeth and alveolar bone for anchorage, good esthetic and functional treatment results were obtained through the application of temporary anchorage devices and proper biomechanics. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Supernumerary teeth in non-syndromic patients

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Mali, Santosh; Karjodkar, Freny Rashmiraj; Sontakke, Subodh; Sansare, Kaustubh [Nair Hospital Dental College, Maharashtra (India)

2012-03-15

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.

Nonsyndromic Bilateral Multiple Impacted Supernumerary Mandibular Third Molars: A Rare and Unusual Case Report

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G. Siva Prasad Reddy

2013-01-01

Full Text Available A supernumerary tooth is that which is present additionally to the normal series and can be found in any region of the dental arch. An impacted tooth is defined as the one which is embedded in the alveolus, so that its eruption is prevented, or the tooth is locked in position by bone or the adjacent teeth. The occurrence of multiple supernumerary teeth in only one patient in the absence of an associated systemic condition or syndrome is considered as a rare phenomenon. The occurrence of supernumerary teeth in the lower molar region is rare. A prevalence of less than 2% of cases occurring in this region has been estimated. Their occurrence presents a clinical problem for orthodontists and oral surgeons. The cause, frequency, complications, and surgical operation of impacted teeth are always interesting subjects for study and research. An impacted tooth can result in caries, pulp disease, periapical and periodontal disease, temporomandibular joint disorder, infection of the fascial space, root resorption of the adjacent tooth, and even oral and maxillofacial tumours. The management of impacted wisdom teeth has changed over the past 20 years from removal of nonsymptomatic third molars to simple observation. The aim of this paper is to present a rare case of bilateral multiple impacted supernumerary mandibular third molars.

Surgical removal versus retention for the management of asymptomatic disease-free impacted wisdom teeth

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Ghaeminia, H.; Perry, J.; Nienhuijs, M.E.L.; Toedtling, V.; Tummers, M.J.; Hoppenreijs, T.J.; Sanden, W.J.M. van der; Mettes, T.G.P.H.

2016-01-01

BACKGROUND: Prophylactic removal of asymptomatic disease-free impacted wisdom teeth is surgical removal of wisdom teeth in the absence of symptoms and with no evidence of local disease. Impacted wisdom teeth may be associated with pathological changes, such as pericoronitis, root resorption, gum and

Successful treatment of multiple bilateral impactions - a case report

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Schubert, Michael; Proff, Peter; Kirschneck, Christian

2016-01-01

Background Successful treatment of patients with multiple bilateral impactions can be an orthodontic challenge, but few reports on treatment planning and execution exist. Case presentation In this case report, we describe the successful orthodontic treatment of a 16.3-year old female patient without systemic or genetic disease with initially nine persisting deciduous and nine impacted permanent teeth with complete root formation and closed apices in both jaws. After extraction of th...

Multidisciplinary management of multiple maxillary anterior supernumerary teeth: a case report.

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Kulkarni, Vinaya Kumar; Reddy, Sampath; Duddu, Mahesh; Reddy, Deepti

2010-03-01

Supernumerary teeth are a relatively frequent disorder of odontogenesis. They may occur alone or in multiple; be unilateral or bilateral; and appear in the maxilla, mandible, or both. Mesiodens is a supernumerary tooth in the anterior maxilla between the two central incisors. This case report describes the treatment of maxillary central incisors displaced and impacted because of the presence of four mesiodens in a 12-year-old boy. After clinical and radiographic examination, surgical removal of the mesiodens and exposure of the maxillary right central incisor was performed. This resulted in a 14-mm space between the displaced central incisors. Successively, fixed orthodontic treatment was planned with cephalometric analysis. The central incisors were brought to the occlusal plane and aligned, and the space between the incisors was redistributed. Remaining minor spaces between the incisors were closed with composite resin buildup.

Wisdom teeth: mankind's future third vice-teeth?

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Zou, DuoHong; Zhao, Jun; Ding, WangHui; Xia, LunGuo; Jang, XinQuan; Huang, YuanLiang

2010-01-01

The third molar teeth (wisdom teeth) represent the last eruption of the teeth in the human dentition. Throughout evolution, the mandible has had a tendency to decrease in size; the third molar teeth are often impacted, resulting in incomplete tooth eruption that often causes clinical pericoronitis, dental caries, and pericemental abscess. Therefore, the wisdom teeth are often extracted. Moreover, wisdom teeth are often removed for clinical orthodontic treatment. On the other hand, tooth loss due to periodontal disease, dental caries, trauma, or a variety of genetic disorders continues to affect people's lives. Autologous tissues for dental tissue regeneration that could replace lost teeth could provide a vital alternative to currently available clinical treatments. To pursue this goal, we hypothesize that human third molar tooth buds can be obtained during development. Human wisdom tooth germination tissue could then be placed into an embryonic stem cell bank for storage. When the donor's other teeth are missing, embryonic stem cell and tissue engineering technologies, will permit the restoration of the missing teeth. Therefore wisdom teeth will be mankind's future third vice-teeth.

Impacted maxillary canines and root resorption of adjacent teeth: A retrospective observational study.

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Guarnieri, R; Cavallini, C; Vernucci, R; Vichi, M; Leonardi, R; Barbato, E

2016-11-01

The prevalence of impacted maxillary canine is reported to be between 1% and 3%. The lack of monitoring and the delay in the treatment of the impacted canine can cause different complications such as: displacement of adjacent teeth, loss of vitality of neighbouring teeth, shortening of the dental arch, follicular cysts, canine ankylosis, recurrent infections, recurrent pain, internal resorption of the canine and the adjacent teeth, external resorption of the canine and the adjacent teeth, combination of these factors. An appropriate diagnosis, accurate predictive analysis and early intervention are likely to prevent such undesirable effects. The objective is to evaluate, by means of a retrospective observational study, the possibility of carrying out a predictive analysis of root resorption adjacent to the impacted canines by means of orthopantomographs, so as to limit the prescription of additional 3D radiography. 120 subjects with unilateral or bilateral maxillary impacted canine were examined and 50 patients with 69 impacted maxillary canine (22 male, 28 female; mean age: 11.7 years) satisfied the inclusion criteria of the study. These patients were subjected to a basic clinical and radiographic investigation (orthopantomographs and computerized tomography). All panoramic films were viewed under standardized conditions for the evaluation of two main variables: maxillary canine angulations (a, b, g angles) and the overlapping between the impacted teeth and the lateral incisor (Analysis of Lindauer). Binary logistic regression was used to estimate the likelihood of resorbed lateral incisors depending on sector location and angle measurements. Results indicated that b angle has the greatest influence on the prediction of root resorption (predictive value of b angle = 76%). If β angle <18° and Lindauer = I, the probability of resorption is 0.06. Evaluation of b angle and superimposition lateral incisor/impacted canine analysed on orthopantomographs could be one of

[Comparison of dentomaxillary pantomography and periapical radiographs with horizontal tube shift in localizing the impacted teeth].

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Wang, Sun; Fan, Lin-feng

2005-04-01

To compare the clinic value between dentomaxillary pantomography and periapical radiographs in localization of the impacted teeth. 43 impacted teeth were localized with both dentomaxillary pantomography technique and periapical radiographs with horizontal tube shift which is clinically widely used. And a comparison between the two methods was carried out using Chi square test. Both dentomaxillary pantomography and periapical radiographs with horizontal tube shift can relatively precisely demonstrate the position of the impacted teeth. The percentage of the cases which the image and the result of surgery was consistent in the two methods was 93.02% and 95.35% (P>0.05) respectively. There was no statistical difference between the two groups. Dentomaxillary pantomography can precisely localize the impacted teeth.

Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

OpenAIRE

Kalaskar, Ritesh R.; Kalaskar, Ashita R.

2011-01-01

Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. ...

Diode Laser Clinical Efficacy and Mini-Invasivity in Surgical Exposure of Impacted Teeth.

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Migliario, Mario; Rizzi, Manuela; Lucchina, Alberta Greco; Renò, Filippo

2016-11-01

The gold standard to arrange impacted teeth in the dental arch is represented by a surgical approach followed by orthodontic traction force application. In the literature, many surgical approaches are proposed to reach such a scope. The aim of the present study is to demonstrate how laser technique could positively assist surgical approaches.Study population was composed by 16 patients undergoing orthodontic treatment of 20 impacted teeth. In 10 patients (population A) surgical exposure of the impacted teeth was performed using a 980 nm diode laser, while in the other 10 patients (population B), surgical incision was performed using a traditional lancet.Only 3 patients of the population A needed local anesthesia for surgical procedure while the remaining 7 patients reported only faint pain during surgery. Two patients referred postsurgical pain (numerical rating scale average value = 2) and needed to take analgesics. None of the patients showed other postsurgical side effects (bleeding, edema).All population B patients needed infiltrative anesthesia and referred postsurgical pain (numerical rating scale average value >4) treated with analgesics. Moreover, in such population, 4 patients referred lips edema while 4 showed bleeding and 6 needed surgical sutures of soft tissues.The lack of side effects of laser surgical approach to expose impacted teeth must persuade dental practitioners to choose such a clinical approach to closed surgical approach every time it is possible.

Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

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Ritesh R Kalaskar

2011-01-01

Full Text Available Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst.

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Kalaskar, Ritesh R; Kalaskar, Ashita R

2011-01-01

Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

Supernumerary teeth: case report and literature review

International Nuclear Information System (INIS)

Bolanos Lopez, Violeta

2008-01-01

Supernumerary teeth (ST) have been an anomaly of tooth development, this is refered to the increase in the number of pieces in the normal dentition. It can be unique, multiple, unilateral or bilateral, normal or altered form; appear erupted, impacted or retained. Both dentitions are affected, but is most common in the permanent. The literature review has covered and mentioned spanned supernumerary teeth, the definition, etiology, characteristics and classification according to number, position and shape; as diagnose, alterations or clinical sequelae - eruptive associated with them and possible treatments to be done when it occurs. The presence of mechanical accidents have been a frequent complication, within this, displacement of adjacent teeth has been the most common; is associated with different syndromes such as lip and palate cleft; however, they can not be related with pathologies; being mesiodens the most frequent. (author) [es

[Use of "gelatamp" colloidal silver gelatin sponge to prevent dry socket after extracting mandibular impacted teeth].

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Wang, Yao-zhong; Guan, Qun-li; Li, Ya-xin; Guo, Ji-lai; Jiang, Ling; Jia, Mu-yun; Deng, Yue

2013-02-01

To study the clinical effect of "gelatamp" colloidal silver gelatin sponge on preventing dry socket after extracting the mandibular impacted teeth. 1350 teeth extracted from 976 patients who needed to extract the mandibular impacted teeth were divided into group A, group B and group C randomly. "Gelatamp" colloidal silver gelatin sponge was implanted into alveolar socket after teeth extraction in group A, with absorbable gelatin sponge was implanted into alveolar socket in group B and nothing was implanted into alveolar socket in group C. The incidence of dry socket was observed, the data was analyzed using SPSS10.0 software package. The incidence of dry socket was 0.44% in group A, 2% in group B and 4.44% in group C. There was significant difference in the incidence of dry socket between group A and group C(Pcolloidal silver gelatin sponge can prevent the occurrence of dry socket after teeth extraction, which is of wide clinical use.

Surgical management of impacted incisors in associate with supernumerary teeth: a combine case report of spontaneous eruption and orthodontic extrusion.

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Das, D; Misra, J

2012-01-01

Maxillary permanent incisors impaction is not a frequent case in dental practice, but its treatment is challenging because of its importance to facial esthetics. Supernumerary teeth are the main cause of impaction of upper incisors. Supernumerary teeth when present can cause both esthetic and pathologic problems. Early detection of such teeth is most important if complications are to be avoided. In this reported case, the orthopantamogram of a 9-year-old boy revealed two impacted supernumerary teeth in the maxillary anterior region, which was interfering with the eruption of the permanent central incisors. The impacted supernumerary teeth were surgically removed, 11 was repositioned in the arch as it was situated very high in the arch, close to the nasal floor. Twenty-one erupted spontaneously but orthodontic force was applied over 11 to bring it into the occlusion and alignment was achieved with 0.014 mm NiTi wire.

Marsupialization of a large dentigerous cyst in the mandible with orthodontic extrusion of three impacted teeth. A case report.

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Abu-Mostafa, Nedal; Abbasi, Arshad

2017-09-01

The dentigerous cyst (DC) is the most common type of developmental odontogenic cyst. It is usually asymptomatic and associated with the crown of an unerupted or impacted tooth. However, after a long duration, it is likely to cause significant bone resorption, cortical expansion, and tooth displacement. This report presents a large infected DC in the mandible of a 12-year-old female patient. The DC was located inferior to badly decayed primary molars and surrounded three impacted permanent teeth: canine, first premolar, which had a dilacerated root, and second premolar. The DC was treated successfully by marsupialization and extrusion of the impacted teeth. In conclusion, the combination of marsupialization with orthodontic extrusion is a conservative, efficient protocol that stimulates bone healing and promotes the eruption of cyst-associated teeth even if they are deeply impacted, crowded, or have a dilacerated root. Key words: Dentigerous cyst, marsupialization, impacted teeth, orthodontic extrusion, dilacerated root.

Assessment of periodontal status following the alignment of impacted permanent maxillary canine teeth.

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Szarmach, I J; Szarmach, J; Waszkiel, D; Paniczko, A

2006-01-01

The aim of the study was to assess the effect of orthodontic movement of the impacted canines after surgical exposure and alignment on the periodontal status of the transpositioned and adjacent teeth as well as to compare certain parameters with those of spontaneously erupted teeth. Twenty-four patients (mean age 18.4 +/- 3.66) with unilaterally impacted 24 canines were enrolled in the study. The following parameters were assessed: pocket depth (PD), clinical attachment level (CAL), platelet index (PI) of Silness and Löe, and modified sulcus bleeding index (SBI). Optic density of the alveolar bone along the root surface of the aligned canine was analysed based on digital radiological images made with the right angle technique. Control group consisted of spontaneously erupted teeth. In comparison to the control group, in the orthodonticaly treated group PD was found to increase on the mesial buccal and palatal surfaces of the first premolar (p aligned canine (p aligned tooth were statistically significant (p alignment zone and the control, and there was no link between the method of treatment and periodontal status, either. The alignment of the impacted permanent maxillary canines poses a risk of periodontal deterioration. Patients subjected to surgical-orthodontic treatment require periodic periodontal follow-ups.

Impact on Dietary Intake of Removable Partial Dentures Replacing a Small Number of Teeth.

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Inomata, Chisato; Ikebe, Kazunori; Okada, Tadashi; Takeshita, Hajime; Maeda, Yoshinobu

2015-01-01

The aim of this study was to clarify the impact of wearing removable partial dentures (RPDs) replacing a small number of teeth on dietary intake. Participants had at least 20 teeth and were classified as Eichner B1 or B2. The participants underwent dental and oral examinations, and their dietary intake was assessed. Analysis of covariance showed that RPD wearers consumed more vegetables, n-3 fatty acids, calcium, vitamin A, and dietary fiber than nonwearers after adjusting for possible confounding factors. It is concluded that RPDs are effective for improving dietary intake even in participants who have lost a small number of teeth.

Perawatan gigi impaksi anterior rahang atas pada remaja (The treatment of maxillary anterior impacted teeth in adolescent

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Herdi Eko Pranjoto

2005-09-01

Full Text Available The incidence of impacted tooth in adolescent is usually found by oral surgeon or orthodontist during their sequence of treatments. The maxillary anterior teeth, especially canine and third lower molar are the most common impacted teeth found as the result of their eruption disturbances. The surgical technique principle is to facilitate the impacted tooth, so that it can be erupted by creating a window and take the bone obstructed surrounding the tooth crown surgically and afterward it is orthodontically tracted. In a case of third molar germ which is predicted to be impacted in mesio version position, germinectomy is preferred to prevent anterior mechanical drive during its development which may cause mal-alignment of the mandibular teeth. Germinectomy which is usually easier than odontectomy, the germ position, and less complication after the surgical intervention are three factors that should be considered in making decision.

Múltiples dientes supernumerarios distomolares Multiple distomolars supernumerary teeth

OpenAIRE

F.J. Rodríguez Romero; S. Cerviño Ferradanes

2009-01-01

En una dentición normal, los dientes supernumerarios son aquellos descritos como adicionales a la serie. La etiología no esta clara. Se han descritos tanto en dentición primaria como en permanente, aunque son mas frecuentes en la dentición permanente. El objetivo de este informe es presentar un caso de una paciente con múltiples dientes supernumerarios distomolares. Cuartos molares bilaterales simétricos son sumamente raros.Supernumerary teeth are described as the teeth formed in excess of th...

Root length and alveolar bone level of impacted canines and adjacent teeth after orthodontic traction: a long-term evaluation

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da SILVA, Aldir Cordeiro; CAPISTRANO, Anderson; de ALMEIDA-PEDRIN, Renata Rodrigues; CARDOSO, Maurício de Almeida; CONTI, Ana Cláudia de Castro Ferreira; CAPELOZZA, Leopoldino

2017-01-01

Abstract Objective The aim of this retrospective study was to evaluate the long-term effects of orthodontic traction on root length and alveolar bone level in impacted canines and adjacent teeth. Material and Methods Sample consisted of 16 patients (nine males and seven females), mean initial age 11 years and 8 months presenting with unilaterally maxillary impacted canines, palatally displaced, treated with the same surgical and orthodontic approach. Teeth from the impacted-canine side were assigned as Group I (GI), and contralateral teeth as control, Group II (GII). The mean age of patients at the end of orthodontic treatment was 14 years and 2 months and the mean post-treatment time was 5 years and 11 months. Both contralateral erupted maxillary canines and adjacent teeth served as control. Root length and alveolar bone level (buccal and palatal) were evaluated on cone-beam computed tomography (CBCT) images. The comparison of root length and alveolar bone level changes between groups were assessed by applying paired t-test, at a significance level of 5% (p<0.05). Results There were no statistically significant differences in root length and buccal and palatal bone levels of canines and adjacent teeth among groups. Conclusions Impacted canine treatment by closed-eruption technique associated with canine crown perforation, has a minimal effect on root length and buccal and palatal alveolar bone level in both canine and adjacent teeth, demonstrating that this treatment protocol has a good long-term prognosis. PMID:28198979

Assisted eruption of impacted teeth into an alveolar bone graft in a patient with cleft lip and palate.

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Peamkaroonrath, Chonthicha; Manosudprasit, Montien; Godfrey, Keith

2008-11-01

To assist the eruption of impacted upper teeth into an alveolar bone graft in a patient with a unilateral cleft lip and palate. An 8-year-old Thai boy with left unilateral complete cleft lip and palate had the chief complaint of anterior crossbite. He presented with a mild skeletal 3, dental Class III subdivision malocclusion, anterior crossbite, left unilateral posterior crossbite, moderate crowding in the upper arch with impaction of upper the left lateral incisor (tooth 22) and canine (tooth 23). In the first phase of treatment the posterior crossbite was corrected with a removable appliance with a 3-way screw. In the second phase the impacted teeth were surgically exposed, moved into the alveolar bone graft and the teeth aligned with fixed appliances. The upper left lateral incisor was extracted because of its questionable longevity. The orthodontic treatment resulted in normal overjet, overbite and an acceptable facial profile. A prosthesis replaced tooth 22. Forced eruption of impacted teeth can be carried out successfully in the cleft patients after an appropriate treatment plan has been formulated and following preparation of alveolar bone graft in the cleft site.

Surgical extraction of impacted teeth in elderly patients. A retrospective analysis of perioperative complications - the experience of a single institution.

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Trybek, Grzegorz; Chruściel-Nogalska, Małgorzata; Machnio, Małgorzata; Smektała, Tomasz; Malinowski, Jerzy; Tutak, Marcin; Sporniak-Tutak, Katarzyna

2016-09-01

The aim of this retrospective study was to investigate the most frequent complications and assess their overall rate associated with the surgical extraction of impacted teeth in an elderly patient population. Oral health needs of the elders are often associated with surgical procedures for the creation of appropriate conditions for any further prosthetic treatment. One such process is the removal of severely decayed, fractured or impacted teeth detrimental to the fit or appearance of dentures. While broken and decayed teeth leave little doubt for their removal, impacted teeth divide opinion, some extreme regarding their prophylactic removal and the appropriate age for the procedure. Material was selected from the archives of an Out-Patient Dental Surgery Clinic of the Regional Centre of Dentistry in Szczecin, from 2002 to 2013. The database was independently screened by two investigators according to inclusion and exclusion criteria. After selection process, all included records were screened using a data extraction form to obtain the necessary data. The total number of impacted teeth was 73, of which 29% were partially impacted. The overall complication rate was 24.6%. The most common complications were as follows: haematoma, nerve disturbances and local infections. Surgical extraction in patients above 60 years of age is fraught with a high risk of possible complications. © 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

The alignment of impacted and ectopic teeth using the Easy-Way-Coil (EWC) System.

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Schubert, Michael

2008-05-01

Teeth that do not spontaneously erupt in the dental arch or are ectopic must normally be surgically exposed. For orthodontic correction a traction device must be attached to the affected tooth over which the already-raised mucoperiosteal flap is lowered to improve the periodontal condition. The author has developed a system at his private orthodontic practice for this purpose, and it has proven itself over a 10-year period. A traction spring is fastened to a lingual button that is attached to the etched tooth surface using an adhesive. The appliance is activated by systematically shortening the spring. A total of 103 patients were treated successfully in this way, 45 of whom had presented a unilaterally ectopic canine requiring an average treatment time of 17.8 months from surgical exposure to removal of the fixed appliance. None of the patients suffered inflammatory reactions in the oral mucosa adjacent to the traction spring during the treatment. Two impacted teeth were ankylosed and could not be aligned. The EWC-System is clinically a reliable, efficient, easy to use and economical system for the alignment of impacted and ectopic teeth.

Case Report: Multiple Unerupted Permanent Teeth Associated with ...

African Journals Online (AJOL)

The present report describes a case of Noonan's syndrome from a dental viewpoint. ... and malocclusions are some of the frequently observed clinical features. ... fixed orthodontic therapy for forced eruption of unerupted permanent teeth.

Multiple calcifying hyperplastic dental follicles: A case report

International Nuclear Information System (INIS)

Aydin, Ulkem; Baykul, Timucin; Yildirim, Benay; Yildirim, Derya; Bozdemir, Esin; Karaduman, Ayse

2013-01-01

This report describes a 31-year-old female patient with six impacted teeth. The crowns of the impacted teeth were surrounded with cyst-like lesions with a mixed internal structure and well-defined cortical borders. Microscopic examination of the specimen obtained from the follicle of the left mandibular third molar tooth revealed loose to moderately dense collagenous connective tissue with abundant calcified material and sparse epithelial islands. A diagnosis of multiple calcifying hyperplastic dental follicles was made.

Multiple calcifying hyperplastic dental follicles: A case report

Energy Technology Data Exchange (ETDEWEB)

Aydin, Ulkem [Dept. of Dentomaxillofacial Radiology, Baskent University Faculty of Dentistry, Ankara (Turkey); Baykul, Timucin [Dept. of Oral and Maxillofacial Surgery, Suleyman Demirel University Faculty of Dentistry, Isparta (Turkey); Yildirim, Benay [Dept. of Oral Pathology, Gazi University Faculty of Dentistry, Ankara (Turkey); Yildirim, Derya; Bozdemir, Esin [Dept. of Dentomaxillofacial Radiology, Suleyman Demirel University Faculty of Dentistry, Isparta (Turkey); Karaduman, Ayse [Atlas Dent Dental Health Center, Aydin (Turkey)

2013-12-15

This report describes a 31-year-old female patient with six impacted teeth. The crowns of the impacted teeth were surrounded with cyst-like lesions with a mixed internal structure and well-defined cortical borders. Microscopic examination of the specimen obtained from the follicle of the left mandibular third molar tooth revealed loose to moderately dense collagenous connective tissue with abundant calcified material and sparse epithelial islands. A diagnosis of multiple calcifying hyperplastic dental follicles was made.

Multiple congenitally missing teeth: treatment outcome with autologous transplantation and orthodontic space closure.

Science.gov (United States)

Fiorentino, Giuseppe; Vecchione, Pietro

2007-11-01

Treatment for patients with congenitally missing teeth can be challenging. The treatment options include retaining the deciduous teeth, extracting the deciduous teeth and allowing the space to close spontaneously, implant replacement, autotransplantation, prosthetic replacement, and orthodontic space closure. Autologous transplantation and space closure with orthodontic appliances are demonstrated in this case report.

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

The psychosocial impacts of implantation on the dental aesthetics of missing anterior teeth patients.

Science.gov (United States)

Chen, P; Yu, S; Zhu, G

2012-12-01

The aim of the current study was to investigate the psychosocial impact of dental aesthetics among patients who received anterior implant-supported prostheses. The current study is a cross-sectional evaluation involving 115 individuals who had gone through treatment at the dental clinics of general hospitals. Participants completed the Chinese version of the psychosocial impact of dental aesthetics questionnaire (PIDAQ) before implantation and six months after crown restoration. Basic demographic information was recorded. Six months after implant crown restoration, participants were asked to self-assess their own oral aesthetics compared to before implantation. A total of 106 patients completed the study. PIDAQ scores correlated significantly with the self-assessment of the degree of oral aesthetics. Six months after crown restoration, the two factors (social impact and aesthetic attitude) decreased and the dental self-confidence score increased significantly compared to pre-implantation scores. Gender and education level significantly affected PIDAQ. Anterior implant-supported prostheses significantly affected the patients' psychosocial perception. Implantation of missing anterior teeth can significantly improve patients' negative psychosocial impact of dental aesthetics. Gender and education level are correlated with the degree of improvement. The PIDAQ can be used in assessing the psychosocial effects of implantation in missing anterior teeth.

Prevalence of Impacted Molar Teeth among Saudi Population in Asir Region, Saudi Arabia - A Retrospective Study of 3 Years.

Science.gov (United States)

Syed, Kamran Bokhari; Zaheer, Kamran Bokhari; Ibrahim, Mohammed; Bagi, Mustafa Abdel; Assiri, Mohammed Abdullah

2013-02-01

To report the prevalence of impacted third molars according to the age, gender and type among Saudi population. This retrospective study involved 3800 panoramic radiographs of subjects aged 18 to 45 years who presented to the College of Dentistry, King Khalid University, Abha, Kingdom of Saudi Arabia for oral care during the period from February 2009 to February 2011. Data collected was entered into a spreadsheet (Excel 2000; Microsoft, US) and analyzed using Statistical Package for Social Sciences (SPSS) version 16.0. A total of 713 impacted teeth were identified (18.76%) (p=0.003). The male to female ratio with impacted third molars was 604:109 (5.54:1) and the ratio of patients with impacted teeth was (5:1). Age group 1 (i.e., 20 to 25 years)had the highest prevalence of third molar tooth impaction (64.5%) and this decreased with increasing age. Incidence of tooth impaction is higher in the mandible than in maxilla. Males had a higher incidence of third molar impaction as compared to the females. Highest incidence is found in the age group of 20-25 years. Mesio-angular impaction was the most predominant type. How to cite this article: Syed KB, Kota Z, Ibrahim M, Bagi MA, Assiri MA. "Prevalence of Impacted Molar Teeth among Saudi Population in Asir Region, Saudi Arabia - A Retrospective Study of 3 Years". J Int Oral Health 2013; 5(1):43-47.

A patient with protrusion and multiple missing teeth treated with autotransplantation and space closure.

Science.gov (United States)

Ko, Jeong-Min; Paik, Cheol-Ho; Choi, Simon; Baek, Seung-Hak

2014-05-01

To present a patient treated with submerging autotransplantation (SA) of an immature premolar and subsequent orthodontic space closure (OSC) and to report a 10-year follow-up result. A 10-year-old boy had multiple missing premolars with an asymmetric pattern (maxillary right first and second premolars, teeth 14 and 15; maxillary left second premolar, tooth 25; and mandibular right second premolar, tooth 45). After considering several treatment options, tooth 35 with immature root development underwent SA into the missing site of tooth 15 at a depth 5 mm below the occlusal plane and was stabilized with sutures to create a symmetric missing condition of the premolars in the four quadrants. Three months after autotransplantation, spontaneous eruption of the transplanted tooth was observed. Nine months after autotransplantation, presence of the lamina dura of the transplanted tooth was confirmed with a periapical radiograph. Active orthodontic treatment was initiated to reduce lip protrusion by closing the missing spaces of teeth 14, 25, 35, and 45 and to correct dental midline deviation. After 33 months of active orthodontic treatment, Class I canine and molar relationships were obtained. During the 10-year follow-up, the pulp vitality of the transplanted tooth was maintained without any pathologic findings, including root resorption or pulp canal obliteration. In a patient with lip protrusion and multiple congenitally missing premolars with an asymmetric pattern, SA of one premolar from the normal quadrant into the quadrant missing two premolars with subsequent OSC of the missing sites of the other premolars can be an effective treatment modality.

[Application of Low Dose Spiral CT in Diagnosing Impacted Teeth in Children and Adolescents].

Science.gov (United States)

Wang, Meng-tian; Li, Xue-sheng; Li, Kai-ming; Bao, Li; Ning, Gang

2015-09-01

[ABSTRACT] To determine the value of low dose spiral CT scanning in diagnosing impacted teeth of children and adolescents. A total of 153 children and adolescents with confirmed impacted teeth in West China Second University Hospital, Sichuan University were enrolled in this study. They were divided into 5 groups according to the different spiral CT scan parameters (tube current time product, scanning thickness and collimation value): Group A (n=30, 330 mAs, 6 X 0. 75 mm and 3. 0 mm), Group B (n=30, 140 mAs, 6 X 0. 75 mm and 3. 0 mm), Group C (n=30, 80 mAs, 6 X 0. 75 mm and 3. 0 mm), Group D (n=31, 80 mAs, 6 X 1. 50 mm and 5. 0 mm), and Group E (n=32, 50 mAs, 6 X 1. 50 mm and 5. 0 mm). There were no significant differences in general clinical features (P>0. 05) among the participants of the five groups. The phantoms were used to measure spatial resolution and contrast resolution of the scan images. Dose length product (DLP) was recorded during CT scanning for calculating effective dose (ED) of exposure. The quality of images was evaluated using a list of quality scoring criteria. (1) Under 330, 140, 80, 80 and 50 mAs, the images had a spatial resolution of 1.0 mm, with contrast resolution of 2. 0, 3. 0, 4. 5, 4. 5 and 6. 0 mm, respectively. (2) Significant differences in ED values were found among the five groups (F=1 064. 119, P=0. 000) and between every two of those groups (P0. 05). The diagnostic results of the spiral CT were consistent with those of orthodontic surgery. Low dose spiral CT scanning can meet the image quality requirements for diagnosing impacted teeth, minimizing radiation exposure effectively.

Endodontic treatment of developmental anomalies in posterior teeth: treatment of geminated/fused teeth--report of two cases.

Science.gov (United States)

Tsesis, I; Steinbock, N; Rosenberg, E; Kaufman, A Y

2003-05-01

Gemination or fusion is a rare occurrence in the mandibular posterior teeth. Endodontic treatment of these teeth needs special care and attention to the bizarre anatomy. The aim of this article is to describe the problems encountered and the strategy in treating such cases. Two cases of complex endodontic treatment of fused/geminated teeth are presented. The first is an 11-year-old girl with an anomalous 'double' first mandibular molar and premolar diagnosed as having necrotic pulp with chronic apical abscess of endodontic origin; the second is a 16-year-old boy with 'double' second and supernumerary mandibular molars, who was diagnosed with irreversible pulpitis. Both cases were treated successfully in multiple appointments. The common features and treatment modalities are discussed. Failure to diagnose fused/geminated teeth leads to misdiagnosis and a treatment plan that could cause permanent damage and tooth loss. Generally, there is communication between root canal systems of fused/geminated teeth which should be treated as one entity. Use of magnification is an important aid during treatment.

Genetics and presence of non-syndromic supernumerary teeth: A mystery case report and review of literature

Directory of Open Access Journals (Sweden)

Neha Khambete

2012-01-01

Full Text Available Presence of supernumerary teeth is well-recognized clinical phenomenon. However, it is uncommon to find multiple supernumeraries in individuals with no other associated disease or syndrome. Presence of multiple supernumerary teeth is thought to have genetic component. We report a rare case where multiple supernumerary teeth were seen without presence of any other syndrome in 3 generations; father, son, and two grandsons. We also present a review of similar cases published in literature till date. The role of genetics in development of supernumerary teeth is highlighted.

Clinical parameter of odontoma with special emphasis on treatment of impacted teeth-a retrospective multicentre study and literature review.

Science.gov (United States)

Kämmerer, Peer W; Schneider, Daniel; Schiegnitz, Eik; Schneider, Sarah; Walter, Christian; Frerich, Bernhard; Kunkel, Martin

2016-09-01

Odontoma-separated into complex (CxOD) and compound (CpOD) subtypes-represents the most frequent odontogenic malformation. Retention of permanent teeth is a common symptom. Therefore, in a series of odontomas, an analysis of the management of retained teeth was conducted. In a retrospective multicenter study of two University Medical Centers and one private praxis in Germany, demographic and clinical data regarding odontomas from 01/2000-03/2015 were obtained. In particular, the influence of operative therapy on the dentition and on the treatment of impacted teeth was analyzed. Forty-five patients with 15 CxOD and 30 CpOD were included. Initial symptoms were delayed eruption of permanent teeth (n = 11), pain (n = 4), and swellings (n = 2); 28 cases were discovered by incidence, all of them via panoramic radiographs. The mandible/maxilla ratio was about 1:0.55 (29/16). Thirty-five out of 45 odontomas were in close proximity of at least one tooth (n = 16 at molars). A total of 14 teeth were extracted (CxOD: n = 5; CpOD: n = 9). Extractions had to be conducted more often in older patients (mean age 39.8 vs. 25.6 years). Of the non-extracted teeth, 8 teeth were displaced and retained. Of those, 4 teeth were aligned in the dental arch via orthodontic help and 2 teeth erupted spontaneously after operation during the follow-up period. In all cases, no relapse was seen. Odontomas can cause displacement as well as malformation and resorption of the adjacent teeth. Mostly, removal of odontomas is conducted. Extirpation of odontoma can allow for normal tooth eruption, often rendering extractions avoidable. Orthodontic alignment, though sometimes challenging, is a reasonable therapeutic option. These findings underline the value of the panoramic radiograph in preventive dentistry in younger patients.

The Effect of Multiple Sulfatase Deficiency (MSD) on Dental Development: Can We Use the Teeth as an Early Diagnostic Tool?

Science.gov (United States)

Zilberman, Uri; Bibi, Haim

2016-01-01

Multiple sulfatase deficiency (MSD) is a rare autosomal recessive inborn error of metabolism due to reduced catalytic activity of the different sulfatase. Affected individuals show neurologic deterioration with mental retardation, skeletal anomalies, organomegaly, and skin changes as in X-linked ichthyosis. The only organ that was not examined in MSD patients is the dentition. To evaluate the effect of the metabolic error on dental development in a patient with the intermediate severe late-infantile form of MSD (S155P). Histological and chemical study were performed on three deciduous and five permanent teeth from MSD patient and pair-matched normal patients. Tooth germ size and enamel thickness were reduced in both deciduous and permanent MSD teeth, and the scalloping feature of the DEJ was missing in MSD teeth causing enamel to break off from the dentin. The mineral components in the enamel and dentin were different. The metabolic error insults the teeth in the stage of organogenesis in both the deciduous and permanent dentition. The end result is teeth with very sharp cusp tips, thin hypomineralized enamel, and exposed dentin due to the break off of enamel. These findings are different from all other types of MPS syndromes.Clinically the phenotype of intermediate severe late-infantile form of MSD appeared during the third year of life. In children of parents that are carriers, we can diagnose the disease as early as birth using X-ray radiograph of the anterior upper region or as early as 6-8 months when the first deciduous tooth erupt and consider very early treatment to ameliorate the symptoms.

Impact velocities of the teeth after a sudden unloading at various initial bite forces, degrees of mouth opening, and distances of travel

NARCIS (Netherlands)

Nagashima, T; Slager, GEC; Broekhuijsen, ML; vanWilligen, JD

A potentially dangerous situation arises when an individual bites on hard and brittle food which suddenly breaks, since the impact velocity of the lower teeth onto the upper teeth after the food is broken can be high and may cause dental damage. The present experiments were designed to study the

About Kids' Teeth

Science.gov (United States)

... wear a mouthguard when playing sports like basketball, soccer, football and hockey. 17 – 21 Years Old The last teeth to appear are wisdom teeth at around ages 17 – 21. By age 21, all 32 of the adult teeth have usually appeared. Learn about Nutrition Baby Teething Baby Teeth and Teething Baby teeth ...

An Evo-Devo perspective on ever-growing teeth in mammals and dental stem cell maintenance

Directory of Open Access Journals (Sweden)

Elodie eRenvoisé

2014-08-01

Full Text Available A major challenge for current evolutionary and developmental biology research is to understand the evolution of morphogenesis and the mechanisms involved. Teeth are well suited for the investigation of developmental processes. In addition, since teeth are composed of hard-mineralized tissues, primarily apatite, that are readily preserved, the evolution of mammals is well documented through their teeth in the fossil record. Hypsodonty, high crowned teeth with shallow roots, and hypselodonty, ever-growing teeth, are convergent innovations that have appeared multiple times since the mammalian radiation 65 million years ago, in all tooth categories (incisors, canines, premolars and molars. A shift to hypsodonty, or hypselodonty, during mammalian evolution is often, but not necessarily, associated with increasingly abrasive diet during important environmental change events. Although the evolution of hypsodonty and hypselodonty is considered to be the result of heterochrony of development, little has been known about the exact developmental mechanisms at the origin of these morphological traits. Developmental biologists have been intrigued by the mechanism of hypselodonty since it requires the maintenance of continuous crown formation during development via stem cell niche activity. Understanding this mechanism may allow bioengineered tooth formation in humans. Hypsodonty and hypselodonty are thus examples of phenotypic features of teeth that have both impacts in understanding the evolution of mammals and holds promise for human tooth bioengineering.

[Rare earth magnets in conjunction with fixed orthodontics. An "attractive" solution for the positioning of impacted teeth].

Science.gov (United States)

Dereudre, B

2001-11-01

Two rare earth permanent magnets are used to align impacted teeth: one is bonded on the crown of the ectopic tooth, the other, intraoral, guides the impacted tooth to the desired place by its attractive power. The intraoral magnet is fixed to an edgewise arch. The adjustments allowed by fixed appliance create better final tooth position than with removable appliance. Our experience depicts an improvement of stability in results and a diminution of periodontal breakdown.

Accuracy of three-dimensional printing for manufacturing replica teeth

OpenAIRE

Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol; Cho, Jin-Hyoung

2015-01-01

Objective Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Methods Fifty extracted molar teeth were selected as samples. They were sc...

Automatic teeth axes calculation for well-aligned teeth using cost profile analysis along teeth center arch.

Science.gov (United States)

Kim, Gyehyun; Lee, Jeongjin; Seo, Jinwook; Lee, Wooshik; Shin, Yeong-Gil; Kim, Bohyoung

2012-04-01

In dental implantology and virtual dental surgery planning using computed tomography (CT) images, the examination of the axes of neighboring and/or biting teeth is important to improve the performance of the masticatory system as well as the aesthetic beauty. However, due to its high connectivity to neighboring teeth and jawbones, a tooth and/or its axis is very elusive to automatically identify in dental CT images. This paper presents a novel method of automatically calculating individual teeth axes. The planes separating the individual teeth are automatically calculated using cost profile analysis along the teeth center arch. In this calculation, a novel plane cost function, which considers the intensity and the gradient, is proposed to favor the teeth separation planes crossing the teeth interstice and suppress the possible inappropriately detected separation planes crossing the soft pulp. The soft pulp and dentine of each individually separated tooth are then segmented by a fast marching method with two newly proposed speed functions considering their own specific anatomical characteristics. The axis of each tooth is finally calculated using principal component analysis on the segmented soft pulp and dentine. In experimental results using 20 clinical datasets, the average angle and minimum distance differences between the teeth axes manually specified by two dentists and automatically calculated by the proposed method were 1.94° ± 0.61° and 1.13 ± 0.56 mm, respectively. The proposed method identified the individual teeth axes accurately, demonstrating that it can give dentists substantial assistance during dental surgery such as dental implant placement and orthognathic surgery.

Single versus multiple visits for endodontic treatment of permanent teeth.

Science.gov (United States)

Manfredi, Maddalena; Figini, Lara; Gagliani, Massimo; Lodi, Giovanni

2016-12-01

assessed the risk of bias in the studies using the Cochrane tool and we assessed the quality of the body of evidence using GRADE criteria. When valid and relevant data were collected, we undertook a meta-analysis of the data using the random-effects model. For dichotomous outcomes, we calculated risk ratios (RRs) and 95% confidence intervals (CIs). For continuous data, we calculated mean differences (MDs) and 95% CIs. We examined potential sources of heterogeneity. We conducted subgroup analyses for necrotic and vital teeth. We included 25 RCTs in the review, with a total of 3780 participants, of whom we analysed 3751. We judged three studies to be at low risk of bias, 14 at high risk, and eight as unclear.Only one study reported data on tooth extraction due to endodontic problems. This study found no difference between treatment in one visit or treatment over multiple visits (1/117 single-visit participants lost a tooth versus 2/103 multiple-visit participants; odds ratio (OR) 0.44, 95% confidence interval (CI) 0.04 to 4.78; very low-quality evidence).We found no evidence of a difference between single-visit and multiple-visit treatment in terms of radiological failure (risk ratio (RR) 0.91, 95% CI 0.68 to 1.21; 1493 participants, 11 studies, I 2 = 18%; low-quality evidence); immediate postoperative pain (dichotomous outcome) (RR 0.99, 95% CI 0.84 to 1.17; 1560 participants, 9 studies, I 2 = 33%; moderate-quality evidence); swelling or flare-up incidence (RR 1.36, 95% CI 0.66 to 2.81; 281 participants, 4 studies, I 2 = 0%; low-quality evidence); sinus tract or fistula formation (RR 0.98, 95% CI 0.15 to 6.48; 345 participants, 2 studies, I 2 = 0%; low-quality evidence); or complications (RR 0.92, 95% CI 0.77 to 1.11; 1686 participants, 10 studies, I 2 = 18%; moderate-quality evidence).The studies suggested people undergoing RoCT in a single visit may be more likely to experience pain in the first week than those whose RoCT was over multiple visits (RR 1.50, 95% CI 0.99 to

Effective of diode laser on teeth enamel in the teeth whitening treatment

Science.gov (United States)

Klunboot, U.; Arayathanitkul, K.; Chitaree, R.; Emarat, N.

2011-12-01

This research purpose is to investigate the changing of teeth color and to study the surface of teeth after treatment by laser diode at different power densities for tooth whitening treatment. In the experiment, human-extracted teeth samples were divided into 7 groups of 6 teeth each. After that laser diode was irradiated to teeth, which were coated by 38% concentration of hydrogen peroxide, during for 20, 30 and 60 seconds at power densities of 10.9 and 52.1 W/cm2. The results of teeth color change were described by the CIEL*a*b* systems and the damage of teeth surface were investigated by scanning electron microscopy (SEM). The results showed that the power density of the laser diode could affect the whiteness of teeth. The high power density caused more luminous teeth than the low power density did, but on the other hand the high power density also caused damage to the teeth surface. Therefore, the laser diode at the low power densities has high efficiency for tooth whitening treatment and it has a potential for other clinical applications.

Correlation between three color coordinates of human teeth

Science.gov (United States)

Lee, Yong-Keun

2014-11-01

The objective was to determine whether there were significant correlations in the three color coordinates within each of two color coordinate systems, such as the Commission Internationale de l'Eclairage (CIE) L*a*b* system, and the lightness, chroma, and hue angle system, of human vital teeth. The color of six maxillary and six mandibular anterior teeth was measured by the Shade Vision System. Pearson correlations between each pair of the color coordinates were determined (α=0.01). The influence of two color coordinates on the other color coordinate was determined with a multiple regression analysis (α=0.01). Based on correlation analyses, all the color coordinate pairs showed significant correlations except for the chroma and hue angle pair. The CIE L* was negatively correlated with the CIE a*, b*, and chroma, but positively correlated with the hue angle. The CIE a* was positively correlated with the CIE b* and chroma. Tooth color coordinates were correlated each other. Lighter teeth were less chromatic both in the CIE a* and b* coordinates. Therefore, it was postulated that the three color coordinates of human teeth were harmonized within certain color attribute ranges, and a lack of correlations in these coordinates might indicate external/internal discolorations and/or anomalies of teeth.

Wisdom Teeth Management

Science.gov (United States)

Wisdom Teeth Management Wisdom teeth, or third molars, are the last teeth to develop and appear in your mouth. They come ... of third molars, disease status, and to suggest management options ranging from removal to a monitored retention ...

Prevalence of Traumatic Dental Injuries to Anterior Teeth of 12-Year-Old School Children in Kashmir, India.

Science.gov (United States)

Ain, Tasneem S; Lingesha Telgi, Ravishankar; Sultan, Saima; Tangade, Pradeep; Ravishankar Telgi, Chaitra; Tirth, Amit; Kumar Pal, Sumit; Gowhar, Owais; Tandon, Vaibhav

2016-03-01

Traumatic dental injuries to anterior teeth are a significant public health problem, not only because their prevalence is relatively high, but also because they have considerable impact on children's daily lives. Traumatic dental injuries (TDIs) cause physical and psychological discomfort, pain and other negative impacts, such as tendency to avoid laughing or smiling, which can affect social relationships. This study aimed to assess the prevalence of traumatic dental injuries to anterior teeth among 12-year-old school children in Kashmir, India. A cross-sectional study was conducted in private and government schools of India among 1600 schoolchildren aged 12 years. In addition to recording of the type of trauma (using Ellis and Davey classification of fractures, 1970), over jet, Angle's molar relation and lip competence were also recorded. The socioeconomic status and academic performance of the study subjects were registered. The data obtained were compiled systematically and then statistically analyzed. The statistical significance for the association between the traumatic injury and the variables was analyzed using the chi-square test. Logistic regression was used to identify potential risk predictors of TDIs. The overall prevalence of TDI to anterior teeth was found to be 9.3%. The TDI to anterior teeth in male was more than female, but the difference was statistically nonsignificant (P Academic performance was found to be significantly associated to TDI to anterior teeth, when analyzed in a multiple regression model. It was concluded that the prevalence of traumatic dental injuries was 9.3%. Traumatic dental injuries among children exhibit complex interaction between the victims' oral conditions and their behavior. Therefore, prevention should consider a number of characteristics such as oral predisposing factors, environmental determinants and human behavior. It is recommended that specific and proper public places for leisure and sports activities, with

Accuracy of three-dimensional printing for manufacturing replica teeth.

Science.gov (United States)

Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol; Cho, Jin-Hyoung

2015-09-01

Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Fifty extracted molar teeth were selected as samples. They were scanned to generate high-resolution 3D surface model stereolithography files. These files were converted into physical models using two types of 3D printing technologies: Fused deposition modeling (FDM) and PolyJet technology. All replica teeth were scanned and 3D images generated. Computer software compared the replica teeth to the original teeth with linear measurements, volumetric measurements, and mean deviation measurements with best-fit alignment. Paired t-tests were used to statistically analyze the measurements. Most measurements of teeth formed using FDM tended to be slightly smaller, while those of the PolyJet replicas tended to be slightly larger, than those of the extracted teeth. Mean deviation measurements with best-fit alignment of FDM and PolyJet group were 0.047 mm and 0.038 mm, respectively. Although there were statistically significant differences, they were regarded as clinically insignificant. This study confirms that FDM and PolyJet technologies are accurate enough to be usable in orthodontic diagnosis and treatment.

[Cryopreservation of teeth].

Science.gov (United States)

Zimmerli, Melanie; Filippi, Andreas

2010-01-01

After tooth loss dental implants or fixed prosthetic restorations are not indicated in children and adolescents due to incomplete maxillary and mandibular development. Cryopreservation is a method for long-term storage of healthy teeth which were removed for orthodontic reasons or due to traumatic origin. These preserved teeth can be used as autogenous replants or transplants after tooth loss. During transport to and from the freezing facilities prior to freezing the teeth are stored in a cell culture medium. The tooth is transferred into a freezing tube containing cell culture medium and cryoprotectant DMSO. Teeth autotransplanted after cryopreservation show vitality of the PDL cells. Usually no enamel and/or dentinal cracks can be observed. After tooth loss transplantation of cryopreserved teeth could be an effective and biological therapy for tooth replacement.

Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

International Nuclear Information System (INIS)

Patters, M.R.; Landsberg, R.L.; Johansson, L.-A.; Trummel, C.L.; Robertson, P.R.

1982-01-01

Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated 45 Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis. (author)

Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

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Patters, M R; Landsberg, R L; Johansson, L A; Trummel, C L; Robertson, P R [Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington, Connecticut, U.S.A.

1982-01-01

Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated /sup 45/Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.

The untreated dental caries in primary teeth: would it be problems?

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Udijanto Tedjosasongko

2016-06-01

Full Text Available Dental caries still remain as the most prevalent oral health disease in children. Many efforts have been done to prevent dental caries in children, but unfortunately there are dental practitioners who still have false mindset and prefer not to treat the dental caries case in primary teeth with the most common reasons are because it will be replaced with the permanent teeth. There are many negative effect will occur if the dental caries treatments in primary teeth are neglected.This topic would review the effects of untreated dental caries in children based on research reports.Severely decayed teeth have an important impact on children’s general health, nutrition, growth and body weight by causing discomfort, pain, sleeping problems, learning disorders and absence from school.  Untreated caries may affect seriously the quality of children’s life because of pain and discomfort, which could lead to acute and chronic infections, oral mucosal conditions and altered eating and sleeping habits. Furthermore, untreated caries in primary teeth can have a lasting detrimental impact on the permanent dentition by causing high caries risk or developmental defects of the permanent successor tooth. Moreover it has been reported that children at each higher level of caries had significantly lower height and weight outcomes than those with lower caries levels. The untreated dental caries in primary teeth would lead the children to poor growth and health which lowering the their quality of life.

Incidence of Radiographic Cystic Lesions Associated With Unerupted Teeth in Dogs.

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Babbitt, Sam G; Krakowski Volker, Mary; Luskin, Ira R

2016-12-01

Medical records and radiographs were retrospectively reviewed over a 3-year period (2012-2015) from dogs presented to a private dental referral practice. Medical records were evaluated for the diagnosis of impacted or embedded teeth. The identified dogs' radiographs were reviewed for the presence of radiographically significant cystic lesions that were associated with the impacted or embedded teeth. Radiographic criteria were established by the authors for the purposes of identifying cystic lesions in dogs of different breeds and sizes, using established indices from human dental pathology as a basis. When histopathology results were available, they were reviewed and reported. In this study, 136 dogs ranging in age from 3 months to 17 years were diagnosed with 213 unerupted teeth during the study period. There were 62 (29.1%) of the 213 radiographically apparent cystic lesions identified based on the criteria proposed in this study. In this study, 146 (68.5%) of the 213 unerupted teeth were identified as mandibular first premolar teeth. Histopathology was obtained on 28 (45.1%) of the 62 diagnosed cystic lesions. Dentigerous cysts accounted for 20 (71.4%) of the 28 cystic lesions. Brachycephalic breeds were overrepresented in this study. Boxer, pug, Shih Tzu, and Boston terrier dogs were most likely to present with cystic lesions associated with unerupted teeth. Seventeen (85%) of the 20 cases with a histopathologic diagnosis of dentigerous cyst were found within these 4 brachycephalic breeds.

Comparative evaluation of different mechanical modifications of denture teeth on bond strength between high-impact acrylic resin and denture teeth: An in vitro study.

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Phukela, Sumit Singh; Chintalapudi, Siddesh Kumar; Sachdeva, Harleen; Dhall, Rupinder Singh; Sharma, Neeraj; Prabhu, Allama

2016-01-01

Acrylic teeth separates from the denture base and remains a major worry in day-to-day routine dental procedure. The present study was conducted to comparatively evaluate different mechanical modifications of acrylic teeth on bond strength between Lucitone 199 heat cure resin and cross-linked teeth. The test specimens, central incisors (21) were demarcated into four groups. Group 1 was the control group, whereas Group 2, Group 3, and Group 4 were experimental groups modified with round groove, vertical groove, and T-shaped groove, respectively. The preparation of masterpiece was done by aligning the long axis of the central incisor teeth at 45° to the base of a wax block (8 mm × 10 mm × 30 mm), with ridge lap surface contacting the base. These test specimen (21) was prepared by Lucitone 199 heat cure resin. Evaluation of bond strength of all the specimens was done using universal tester (materials testing machine). Shapiro-Wilk Test, one-way analysis of variance (ANOVA), and Bonferroni test were done to do statistical investigation. Group 1 specimens prepared by Lucitone 199 heat cure resin showed the lowest bond strength and Group 4 specimens prepared with T-shaped groove packed with Lucitone 199 exhibited the highest bond strength. The bond strength between Lucitone 199 heat cure resin and cross-linked teeth was increased when mechanical modifications was done on denture teeth. The specimens prepared with T-shaped groove packed with Lucitone 199 heat cure resin showed the highest bond strength followed by Group 3, Group 2, and lastly Group 1 prepared by Lucitone 199 heat cure resin.

Primate dental ecology: How teeth respond to the environment.

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Cuozzo, Frank P; Ungar, Peter S; Sauther, Michelle L

2012-06-01

Teeth are central for the study of ecology, as teeth are at the direct interface between an organism and its environment. Recent years have witnessed a rapid growth in the use of teeth to understand a broad range of topics in living and fossil primate biology. This in part reflects new techniques for assessing ways in which teeth respond to, and interact with, an organism's environment. Long-term studies of wild primate populations that integrate dental analyses have also provided a new context for understanding primate interactions with their environments. These new techniques and long-term field studies have allowed the development of a new perspective-dental ecology. We define dental ecology as the broad study of how teeth respond to, or interact with, the environment. This includes identifying patterns of dental pathology and tooth use-wear, as they reflect feeding ecology, behavior, and habitat variation, including areas impacted by anthropogenic disturbance, and how dental development can reflect environmental change and/or stress. The dental ecology approach, built on collaboration between dental experts and ecologists, holds the potential to provide an important theoretical and practical framework for inferring ecology and behavior of fossil forms, for assessing environmental change in living populations, and for understanding ways in which habitat impacts primate growth and development. This symposium issue brings together experts on dental morphology, growth and development, tooth wear and health, primate ecology, and paleontology, to explore the broad application of dental ecology to questions of how living and fossil primates interact with their environments. Copyright © 2012 Wiley Periodicals, Inc.

[Multiple agenesis and prosthetic restoration].

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Renault, P

1990-03-01

Cases of multiple agenesia present some difficulties in the treatment planing. Three situations may be encountered: limited agenesia, restored by a fixed, bonded or cemented prosthesis, multiple uni- or bimaxillary agenesia without remaining of deciduous teeth, restored by a fixed, bonded or cemented prosthesis or the partial adjacent prosthesis, multiple uni- or bimaxillary agenesia with remaining of deciduous teeth, restored by means of a supra-dental prosthesis. The first two situations have been described in dental literature and are relatively easy to treat. The same is not true for the third situation, where the decision to keep the temporary teeth considerably increases the difficulty of prosthetic restoration. This subject will be illustrated by the presentation of a clinical case of multiple bi-maxillary agenesia. The patient has: on the maxilla: an absence of 9 permanent teeth (18, 15, 14, 12, 22, 23, 24, 25, 28) and the presence of 4 deciduous teeth (62, 63, 64, 65), on the mandible: an absence of all permanent teeth, with the exception of 36 and 46, and the remaining of 4 deciduous teeth (75, 73, 83, 84). The remaining of deciduous teeth and the presence of a very high inter-arch space led to opting for dental coverage so as to keep the deciduous teeth and a proper vertical dimension. The patient wished to solve his "problem" in the maxilla first, and is not wanting to undergo the extraction of his deciduous teeth. The following therapeutic proposal was adapted: On the maxilla, a three-step procedure: first step: building of metal copings on 13, 16 and 26 and metal-ceramic crowns on 11 and 21, second step: building of telescop crowns on 16 and 26 and clasps on 13, 11 and 21, third step: casting of the removable partial denture framework and soldering to the telescop crowns and clasps. On the mandible, a provisional restoration using a supra-dental resin removable partial denture with ceramic occlusal surfaces was adopted. The aesthetic and functional

Lead levels in deciduous teeth of children in Bahrain.

Science.gov (United States)

al-Mahroos, F; al-Saleh, F S

1997-06-01

To determine lead exposure among children in Bahrain, a total of 280 shed deciduous whole teeth were collected from 269 children. Teeth were analyzed for lead concentrations using atomic absorption spectrophotometry with electrothermal atomization. Children were between 5 and 15 years old. The study period extended from July 1993 to April 1994. The study showed that the overall mean tooth-lead level was 4.3 micrograms/g dry weight with a range of 0.1-60.8 micrograms/g dry weight. The cumulative frequency distribution revealed that 35% of the teeth had a lead concentration of more than 4 micrograms/g dry weight. The tooth-lead concentrations differed according to the tooth type age. The child's sex, nationality, area of residence and socio-economic status had no impact on tooth-lead level. In conclusion, lead is present in toxic concentrations in 35% of the teeth of the children studied. Urgent measures are needed to eliminate lead from gasoline, paint and other sources in the environment.

Supernumerary teeth in clinical practice

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Anna K. Szkaradkiewicz

2011-07-01

Full Text Available Introduction: Hyperdontia is the condition of having supernumerary teeth, or teeth which appear in addition to the regular number of teeth. The prevalence rates of supernumerary teeth in the permanent dentition amounts 0.1-6.9%, and in deciduous dentition 0.4-0.8%. The presence of supernumerary teeth can be found in everyday dental practice.Case presentation: We describe 3 cases of patients with supernumerary teeth. First patient had supernumerary lateral incisor 12s, second - premolar fused, multicuspid, supernumerary deciduous tooth 64s of having several interconnected roots, and third - erupted odontoma between teeth 13 and 14. In all cases treatment involved the removal of the supernumerary tooth.Conclusions: The decision on proceeding with the supernumerary teeth should be based on the full clinical picture and interview. Early diagnosis and removal of supernumerary teeth allow to avoid or reduce possible complications.

[Comparative study of complications among routine method,high speed turbine handpiece and piezosurgery device after extraction of impacted wisdom teeth].

Science.gov (United States)

Guo, Zhao-zhong; Zhang, Heng; Li, Yan; Li, Xin; Liu, Yin; Wang, Yang; Yuan, Chun-xia; Liu, Xue

2012-04-01

To investigate complications in extraction of complicated impacted wisdom teeth whose root apex near to the inferior alveolar nerve(IAN) by using routine method(chisels),high speed turbine handpiece and piezosurgery device respectively. Three hundred qualified patients with impacted wisdom teeth were divided into three groups randomly,one hundred patients in group A were extracted by routine method, one hundred patients in group B were extracted by high speed turbine handpiece, and one hundred patients in group C were extracted by piezosurgery device. The operation time, postoperative pain duration,dry socket and IAN injury were compared between each two groups. All statistical analysis was performed using SPSS 13.0 software package. Differences between groups were compared using a paired t test (quantitative data) or Chi-square test (qualitative data). The operation time in group A was(14.12±0.12)min, (7.22±0.15)min in group B, (25.23±0.32)min in group C; Significant difference was found between group A and group B(Ppiezosurgery device is more effective in reducing postoperative complications.

Determination of iron, cobalt and zinc in caries teeth by neutron activation analysis

International Nuclear Information System (INIS)

Moriwaki, Kazunari; Shimpuku, Yasuhiro; Furuyama, Shunsuke

1999-01-01

The concentration of Fe, Zn and Co in caries teeth was determined by neutron activation analysis to compare with those of complete impacted wisdom teeth. In order to investigate the distribution of three elements, molar teeth were separated not by conventional method like precipitation or UV absorption method but by ashing method. Furthermore, the same elements for dental pulp and softened dentin were determined. The following results were obtained: The concentration of three elements (Fe, Zn and Co) in enamel, dentin and cementum of caries teeth was higher than that in control teeth. Enamel contained more Fe and Co than those in dentin or cementum, whereas Zn was found to be evenly distributed in three parts of the teeth. The concentration of the elements was Zn>Fe>Co in softened dentin, Fe>Zn>Co in dental pulp. (author)

Relationship between crown placement and the survival of endodontically treated teeth.

Science.gov (United States)

Aquilino, Steven A; Caplan, Daniel J

2002-03-01

Crowns have been considered the restoration of choice for endodontically treated teeth, but their selection has been based primarily on anecdotal evidence. This study tested the hypothesis that crown placement (coronal coverage) is associated with improved survival of endodontically treated teeth when preaccess, endodontic, and restorative factors are controlled. A University of Iowa College of Dentistry treatment database was used to identify permanent teeth that had undergone initial obturation between July 1, 1985, and December 31, 1987. Study patients were restricted to persons with at least 1 dental visit in each 2-year interval from 1985 to 1996; a simple random sample of 280 patients (n = 400 teeth) was selected. Dental charts, radiographs, and computerized databases were examined to ascertain variables of interest and to verify study inclusion criteria. Kaplan-Meier survival estimates were generated for the 203 teeth that satisfied study inclusion criteria. Multivariate Cox proportional hazards regression models were developed, with standard errors adjusted to account for clustering of teeth within patients. When tooth type and radiographic evidence of caries at access were controlled, the final Cox model showed that endodontically treated teeth not crowned after obturation were lost at a 6.0 times greater rate than teeth crowned after obturation (95% confidence interval: 3.2 to 11.3). Within the limitations of this study, a strong association between crown placement and the survival of endodontically treated teeth was observed. These results may impact treatment planning if long-term tooth retention is the primary goal.

Shaping of Rack Cutter Original Profile for Fine-module Ratchet Teeth Cutting

Science.gov (United States)

Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.

2018-05-01

The design models and the process of shaping the cutting edges of the rack cutter for cutting fine-module ratchet teeth are considered in the article. The use of fine-module ratchet teeth can reduce the noise and impact loads during operation of the freewheel mechanisms. Mathematical dependencies for calculating the coordinates determining the geometric position of the points of the front and back edges of the cutting profile of the rack cutter, the workpiece angle of rotation during cutting the ratchet teeth were obtained. When applying the developed method, the initial data are: the radii of the workpiece circumferences passing through the dedendum of the external and internal cut teeth; gradient angles of the front and back edges of the rail.

Trace Elements in Teeth by ICPMS

International Nuclear Information System (INIS)

Zahran, N.F.; Helal, A.I.; Amr, M.A.; Amr, M.A.; Al-saad, K.A.

2008-01-01

Teeth are reported to be suitable indicators of trace element exposure from environment and nutritional status. Inductively coupled plasma mass spectrometry (ICP-MS) is used to compare the trace element content of children's primary teeth and adult teeth. Primary teeth are collected from 28 children and 42 adult from non-industrial City. The data are assessed statistically using t-tests. The adult teeth contained significantly greater concentrations of Na, Mg, Al, Fe, Ni, Cu, Sr, Cd, Ba, Pb and U and significantly less Mn, Co, As, Se, Mo and Bi than the children teeth. Additional measurements on adult teeth pulps are performed. Comparison between trace element concentrations in health and caries teeth pulps show that the mean concentrations of Na, Al, K, Cr, Mn, Co, Cu, Zn, Mo, Ag, Bi and U are lower in caries than healthy teeth pulps. On the other hand, the mean concentrations of Mg, Cd and Pb are higher in caries samples than healthy teeth pulps

Multiple impacts in dissipative granular chains

CERN Document Server

Nguyen, Ngoc Son

2014-01-01

The extension of collision models for single impacts between two bodies, to the case of multiple impacts (which take place when several collisions occur at the same time in a multibody system) is a challenge in Solid Mechanics, due to the complexity of such phenomena, even in the frictionless case. This monograph aims at presenting the main multiple collision rules proposed in the literature. Such collisions typically occur in granular materials, the simplest of which are made of chains of aligned balls. These chains are used throughout the book to analyze various multiple impact rules which extend the classical Newton (kinematic restitution), Poisson (kinetic restitution) and Darboux-Keller (energetic or kinetic restitution) approaches for impact modelling. The shock dynamics in various types of chains of aligned balls (monodisperse, tapered, decorated, stepped chains) is carefully studied and shown to depend on several parameters: restitution coefficients, contact stiffness ratios, elasticity coefficients (...

Teeth re-whitening effect of strawberry juice on coffee stained teeth

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Annisya Pramesti

2018-01-01

Full Text Available Many people favor coffee. However, regarding health and aesthetic dentistry, coffee gives a negative effect. Tanin in coffee causes a brown stain on the tooth surface. Therefore, in aesthetic dental care, teeth whitening has become popular matter. One of the natural ingredients used for teeth whitening treatment is strawberry. The purpose of this study was to obtained data regarding the effect of strawberry juice on the re-whitening process of the coffee-stained tooth enamel surface. This study was a pure experimental in-vitro using Friedman and Wilcoxon Matched Pairs Tests for statistical analysis. The population of this study was anterior teeth. The samples were maxillary central incisors. The sampling technique using sample size determination based on the testing formulas of the difference of two average data pairs resulted in 11 specimens. The result of the research showed that all coffee-stained teeth sample had an increasing enamel colour index. The samples were then applied with strawberry juice resulted in a significant average difference colour index value indicated by p<0.001. The conclusion of this research indicated that there was an effect of strawberry juice on the coffee-stained teeth re-whitening process.

Syndromes with supernumerary teeth.

Science.gov (United States)

Lubinsky, Mark; Kantaputra, Piranit Nik

2016-10-01

While most supernumerary teeth are idiopathic, they can be associated with a number of Mendelian syndromes. However, this can also be a coincidental finding, since supernumerary teeth occur in 6% or more of the normal population. To better define this relationship, we analyzed the evidence for specific associations. We excluded conditions with a single affected patient reported, supernumerary teeth adjacent to clefts or other forms of alveolar disruption (as secondary rather than primary findings), and natal teeth, which can involve premature eruption of a normal tooth. Since, the cause of supernumerary teeth shows considerable heterogeneity, certain findings are less likely to be coincidental, such as five or more supernumerary teeth in a single patient, or locations outside of the premaxilla. We found only eight genetic syndromes with strong evidence for an association: cleidocranial dysplasia; familial adenomatous polyposis; trichorhinophalangeal syndrome, type I; Rubinstein-Taybi syndrome; Nance-Horan syndrome; Opitz BBB/G syndrome; oculofaciocardiodental syndrome; and autosomal dominant Robinow syndrome. There is also suggestive evidence of an association with two uncommon disorders, Kreiborg-Pakistani syndrome (craniosynostosis and dental anomalies), and insulin-resistant diabetes mellitus with acanthosisnigricans. An association of a Mendelian disorder with a low frequency manifestation of supernumerary teeth is difficult to exclude without large numbers, but several commonly cited syndromes lacked evidence for clear association, including Hallermann-Streiff syndrome, Fabry disease, Ehlers-Danlos syndrome, Apert and Crouzon syndromes, Zimmermann-Laband syndrome, and Ellis-van Creveld syndrome. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Crack arrest within teeth at the dentinoenamel junction caused by elastic modulus mismatch

OpenAIRE

Bechtle, Sabine

2010-01-01

Enamel and dentin compose the crowns of human teeth. They are joined at the dentinoenamel junction (DEJ) which is a very strong and well-bonded interface unlikely to fail within healthy teeth despite the formation of multiple cracks within enamel during a lifetime of exposure to masticatory forces. These cracks commonly are arrested when reaching the DEJ. The phenomenon of crack arrest at the DEJ is described in many publications but there is little consensus on the underlying cause and mecha...

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth

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Khalid A. Arafa

2016-01-01

Full Text Available Objectives: To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. Methods: A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group received overdentures with cuspless teeth. The rate of implant success was assessed clinically and radiographically at 3, 6, 9, and 12 months. The data were collected by a questionnaire, an observation checklist, and radiography. The data were then analyzed using computerized methods. Results: Overdentures with cusped teeth showed a significant improvement in the clinical criteria, including the absence of clinical implant mobility, pain, and bone resorption, while the clinical criteria for the absence of peri-implant radiolucency were insignificantly different between the 2 groups (p>0.05. There were no significant differences in the clinical evaluations for bone levels at the time of insertion or 3 months after insertions, while significant differences were found at 6, 9, and 12 months after insertion. Conclusion: Overdentures with cusped teeth supported by immediate implants were found superior regarding many clinical criteria than those cuspless counterparts.

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth.

Science.gov (United States)

Arafa, Khalid A

2016-01-01

To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group received overdentures with cuspless teeth. The rate of implant success was assessed clinically and radiographically at 3, 6, 9, and 12 months. The data were collected by a questionnaire, an observation checklist, and radiography. The data were then analyzed using computerized methods.  Overdentures with cusped teeth showed a significant improvement in the clinical criteria, including the absence of clinical implant mobility, pain, and bone resorption, while the clinical criteria for the absence of peri-implant radiolucency were insignificantly different between the 2 groups (p more than 0.05). There were no significant differences in the clinical evaluations for bone levels at the time of insertion or 3 months after insertions, while significant differences were found at 6, 9, and 12 months after insertion. Overdentures with cusped teeth supported by immediate implants were found superior regarding many clinical criteria than those cuspless counterparts.

Associations between the number of natural teeth in postmenopausal women and hormone replacement therapy.

Science.gov (United States)

Han, Kyungdo; Ko, Youngkyung; Park, Yong-Gyu; Park, Jun-Beom

2016-12-01

Increasing research suggests that periodontal status is associated with hormone replacement therapy in postmenopausal women. This study was performed to assess the relationship between the number of natural teeth and ever use of hormone replacement therapy in postmenopausal women using nationally representative Korean data. Data from the Korea National Health and Nutrition Examination Survey between 2010 and 2012 were used, and the analysis in this study was confined to a total of 4869 respondents over 19 years old who had gone through menopause and who had no missing data for the reproductive factors and outcome variables in that study. The total number of natural teeth was then calculated after excluding third molars. The time of day when tooth brushing was done was recorded as representative oral health behavior. Multiple logistic regression analyses were used to assess association between the number of natural teeth and the use of hormone replacement therapy. Among participants who had ever used hormone replacement therapy, the proportions (percentage and standard error) with no teeth, 1-9 teeth, 10-19 teeth, 20-27 teeth, and 28 teeth were 5.0±2.4%, 6.7±1.4%, 12.5±1.7%, 18.9±1.0%, and 20.7±1.6%, respectively (Preplacement therapy, after adjustments. The analysis revealed that the use of hormone replacement therapy by postmenopausal women showed positive effects for retention of natural teeth. Lack of hormone replacement therapy may be considered to be an independent risk indicator for tooth loss in Korean postmenopausal women. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Esthetic, occlusal, and periodontal rehabilitation of anterior teeth with minimum thickness porcelain laminate veneers.

Science.gov (United States)

da Cunha, Leonardo Fernandes; Pedroche, Lorena Oliveira; Gonzaga, Carla Castiglia; Furuse, Adilson Yoshio

2014-12-01

Ceramic veneers of minimum thickness provide satisfactory esthetic outcomes while preserving the dental structure. Dental ceramics can both improve the esthetic appearance and reestablish the strength and function of teeth. In worn anterior teeth, functional surfaces, for example, anterior and lateral guidance, can be restored effectively. The characteristics of dental ceramics, such as color stability and mechanical and optical properties, make this material a good choice for indirect restorations, especially when optimum function and esthetics are required. This clinical report presents an occlusal, periodontal, and restorative solution with minimum thickness glass ceramic veneers for worn anterior teeth with multiple diastemas. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Non-syndromic multiple odontogenic keratocysts associated with dental anomalies: A report of unusual case and its management

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Sulabha A Narsapur

2015-01-01

Full Text Available Odontogenic keratocyst (OKC, now known as keratocystic odontogenic tumor (KCOT, is the most common cystic lesion occurring in the maxillofacial region. Multiple occurrence of these cysts is less frequent and is usually associated with syndromes, the most common being the Gorlin Goltz syndrome or the nevoid basal cell carcinoma syndrome (NBCCS. We hereby report an unusual case of multiple OKCs in a healthy adult, associated with other dental anomalies. Management approach consisted of enucleation with curettage of the smaller lesions and decortication of buccal cortex in the large lesion. The condition in the present case may be because of the multifocal nature of OKC rather than its association with any syndrome. Concomitant occurrence of multiple OKCs with other dental anomalies may be coincidental. Impacted teeth or missing teeth must be radiographed to rule out the lesions associated with them.

On The Evolution of Human Jaws and Teeth: A Review

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Serhat Yalcin

2011-06-01

Full Text Available The jaws and teeth of Homo sapiens have evolved, from the last common ancestor of chimpanzee and men to their current form. Many factors such as the foods eaten and the processing of foods by fire and tools have effected this evolution course. The evolution of the masticatory complex is related to other anatomical features such as brain size and bipedal posture, and leads to important proceedings like the formation of speech and language. In this review, the evolution of human jaws and teeth and its impact on the general course of human evolution is discussed.

Patients’ general satisfaction with the appearance of anterior maxillary teeth

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Lajnert Vlatka

2017-01-01

Full Text Available Background/Aim. Dental appearance plays an important role in practically all personal social interactions. The main factors that define the dental appearance are tooth colour, shape and position, quality of restoration, and the general position of the teeth in arch, especially in the anterior region. The aim of this study was to evaluate the impact of dental status (tooth shape, fracture, dental and prosthetic restorations and presence of plaque on patient''s satisfaction with the dental appearance, controlling for the age and gender. Methods. A total of 700 Caucasian subjects (439 women aged 18–86 (median 45 years participated in the cross-sectional study. Study included clinical examination and self-administrated questionnaire based on selfperceived aesthetics and satisfaction with the appearance of their maxillary anterior teeth. Results. A regression analysis demonstrated that presence of dental plaque, tooth fracture, composite fillings and crowns had significant independent contribution and were negative predictors of satisfaction with teeth appearance. Participants with presence of plaque on upper teeth (p < 0.001, fractures (p = 0.005, composite fillings (p < 0.001 and crowns (p = 0.032 were less satisfied than those without it. Model explains 12% or variance of general satisfaction with the appearance of maxillary frontal teeth (p < 0.001 and the major contributors are composite fillings (5.3% and plaque (3.2%. Tooth shape, age and gender were not significant predictors of satisfaction. Conclusion. Satisfaction with the teeth appearance is under the influence of many factors with significant negative influence of presence of dental plaque, fractures, composite restorations, and crowns.

A rare case of retained fourth molar teeth in maxilla and mandible. Case report

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Rahnama Mansur

2014-06-01

Full Text Available The study presents a case of the rarely occurring totally retained fourth molar teeth simultaneously in maxilla and mandible. The appearance of supernumerary teeth is a relatively uncommon dental anomaly and it is rare for patients to have impacted fourth molars in two quadrant. The aim of this work is to describe the presence of unilateral (right fourth molars in the maxilla and the mandible in a young female patient aged 24 years. Orthopantomogram revealed impacted lower third molars but also unerupted unilateral (right upper and lower fourth molars. Before orthodontic treatment, the patient was subsequently admitted for removal of third and fourth impacted upper and lower molars under local anesthesia.

[Sequence orthodontic treatment of impacted dilacerated maxillary central incisors].

Science.gov (United States)

Zheng, Yi; Pang, Xuannai; Nan, Lan; Mo, Shuixue

2012-06-01

To explore an effective orthodontic method for treating impacted dilacerated maxillary central incisors. 12 impacted teeth of 11 cases were chosen. The position of the impacted teeth and the relations with neighbour tissues were assessed by X-ray images, oral examination and plaster model, etc. The impacted teeth were induced to erupt with the closed-eruption technique and fixed orthodontic appliances, root canal therapy, apicoectomy and prosthetic treatment. 12 impacted teeth were moved into arches, and the occlusal relationship was normal. There were no root resorption or conglutination in those impacted teeth. The labial impacted teeth of nine cases had bigger labial crown torsion. The root apexes of four impacted teeth were palpable under mucosa of the labial sulcus and operated by root canal therapy and apicoectomy. One of them received prosthetic treatment. Others (five cases) hadn't accepted root canal therapy, and were observed temporarily. The effects of two palatal impacted teeth was stable. It was a good method to expand indication with sequence orthodontic treatment. The impacted dilacerated maxillary central incisors could be aligned with good esthetical and functional effect.

Hospitalisation for the surgical removal of impacted teeth: Has Australia followed international trends?

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Roslind Preethi George

2011-08-01

Full Text Available BackgroundThe aim of the study was to undertake a six-year analysisfrom 1999/00 to 2004/05, of the demographiccharacteristics of hospitalisations for the surgical removal ofimpacted teeth in Western Australia under generalanaesthesia.MethodData for the current analysis was obtained from theWestern Australian Hospital Morbidity Data System(HMDS. Gender, age, indigenous status, place of residence,type of hospital admitted, insurance status, and DiagnosticRelated Group (DRG cost estimates for the procedure wereanalysed.ResultsA total of 37.6% of all oral health-related hospitalisations inWestern Australia over the six years were for the removal ofimpacted teeth. Admitted patients were predominantlyfemales (58.8% and very few Indigenous people werehospitalised (0.2%. The average age of patients was 21.4years (sd=9.9. Metropolitan patients were hospitalised 1.5times more than rural patients for this condition. Themajority of patients were hospitalised at a privatemetropolitan hospital and were insured. The total cost ofhospitalisation for this condition contributes to 27% of allthe oral health condition-related hospitalisation costs.ConclusionThis study suggests that the hospital-based removal ofimpacted teeth in Western Australia is associated withfactors such as indigenous status, age, gender and privatehospital access along with insurance status raisinginteresting questions over the equity of provision of thisservice.

Shark teeth as edged weapons: serrated teeth of three species of selachians.

Science.gov (United States)

Moyer, Joshua K; Bemis, William E

2017-02-01

Prior to European contact, South Pacific islanders used serrated shark teeth as components of tools and weapons. They did this because serrated shark teeth are remarkably effective at slicing through soft tissues. To understand more about the forms and functions of serrated shark teeth, we examined the morphology and histology of tooth serrations in three species: the Tiger Shark (Galeocerdo cuvier), Blue Shark (Prionace glauca), and White Shark (Carcharodon carcharias). We show that there are two basic types of serrations. A primary serration consists of three layers of enameloid with underlying dentine filling the serration's base. All three species studied have primary serrations, although the dentine component differs (orthodentine in Tiger and Blue Sharks; osteodentine in the White Shark). Smaller secondary serrations are found in the Tiger Shark, formed solely by enameloid with no contribution from underlying dentine. Secondary serrations are effectively "serrations within serrations" that allow teeth to cut at different scales. We propose that the cutting edges of Tiger Shark teeth, equipped with serrations at different scales, are linked to a diet that includes large, hard-shelled prey (e.g., sea turtles) as well as smaller, softer prey such as fishes. We discuss other aspects of serration form and function by making analogies to man-made cutting implements, such as knives and saws. Copyright © 2016 Elsevier GmbH. All rights reserved.

Multiplicity distributions in impact parameter space

International Nuclear Information System (INIS)

Wakano, Masami

1976-01-01

A definition for the average multiplicity of pions as a function of momentum transfer and total energy in the high energy proton-proton collisions is proposed by using the n-pion production differential cross section with the given momentum transfer from a proton to other final products and the given energy of the latter. Contributions from nondiffractive and diffractive processes are formulated in a multi-Regge model. We define a relationship between impact parameter and momentum transfer in the sense of classical theory for inelastic processes and we obtain the average multiplicity of pions as a function of impact parameter and total energy from the corresponding quantity afore-mentioned. By comparing this quantity with the square root of the opaqueness at given impact parameter, we conclude that the overlap of localized constituents is important in determining the opaqueness at given impact parameter in a collision of two hadrons. (auth.)

Endotoxin content in endodontically involved teeth. 1975.

Science.gov (United States)

Schein, Benjamin; Schilder, Herbert

2006-04-01

Fluid was aspirated from the root canals of 40 endodontically involved teeth. This fluid was assayed for endotoxin with the limulus lysate test. Pulpless teeth contained greater concentrations of endotoxin than those with vital pulps. Symptomatic teeth also contained more endotoxin than asymptomatic teeth.

Treatment of chronic periodontitis and its impact on mastication.

Science.gov (United States)

Pereira, Luciano J; Gazolla, Cátia M; Magalhães, Isabela B; Ramos-Jorge, Maria Letícia; Marques, Leandro S; Gameiro, Gustavo H; Fonseca, Douglas C; Castelo, Paula M

2011-02-01

The aim of the present study is to assess the impact of conventional periodontal treatment of chronic periodontitis on the perception of mastication. The patients (n = 28; age range: 23 to 56 years, mean age: 37.9 years) were evaluated on two occasions (before and after treatment) with a 45-day interval using the Oral Impact on Daily Performance questionnaire. An electromyography system was used for the determination of activity in muscles of mastication and bite force. Masticatory performance was assessed using a test material. The median particle size of the masticated material was determined using a sieve method and the Rosin-Rammler equation. The clinical criteria were the number of teeth and probing depth, both determined by a single calibrated observer masked to the treatment phase. The data were analyzed in the pretreatment and post-treatment periods using Wilcoxon test; Spearman correlation coefficient; and two multiple linear regression models (backward stepwise procedure). There was a significant negative correlation between the number of teeth (number of mastication units) and difficulty eating (P mastication diminished after periodontal treatment. The number of teeth had considerable importance in the perception of impact on mastication in the sample studied.

Bilaterally impacted mandibular supernumerary premolars associated with unusual clinical complications

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Zameer Pasha

2013-01-01

Full Text Available Supernumerary teeth are extra teeth in comparison to the normal dentition. Their prevalence varies between 0.1% and 3.8%. Supernumeraries are more common in permanent dentition and its incidence is higher in maxillary incisor region, followed by maxillary third molar and mandibular molar, premolar, canine, and lateral incisor. The prevalence of supernumerary premolars is between 0.075-0.26%, and they may occur in single or multiple numbers Bilateral occurrence is uncommon and large percentage of supernumerary premolars remains impacted, unerupted, and usually asymptomatic; radiograph plays an important role in diagnosis of these. The present paper reports a case of bilaterally impacted completely developed supernumerary premolars associated with common clinical complication in unusual manner along with taurodontism of the upper and lower molars.

Classical music and the teeth.

Science.gov (United States)

Eramo, Stefano; Di Biase, Mary Jo; De Carolis, Carlo

2013-01-01

Teeth and their pathologies are frequent themes in classical music. The teeth have inspired popular songwriters such as Thomas Crecquillon, Carl Loewe, Amilcare Ponchielli & Christian Sinding; as well as composers whose works are still played all over the world, such as Robert Schumann and Jacques Offenbach. This paper examines several selections in which the inspiring theme is the teeth and the pain they can cause, from the suffering of toothache, to the happier occasion of a baby's first tooth.

Changes in the chemical composition of mineralised teeth in children after antineoplastic treatment.

Science.gov (United States)

Krasuska-Sławińska, Ewa; Dembowska-Bagińska, Bożenna; Brożyna, Agnieszka; Olczak-Kowalczyk, Dorota; Czarnowska, Elżbieta; Sowińska, Agnieszka

2018-01-01

Chemotherapy, neoplasms, and their complications linked to malabsorption, malnutrition, and metabolic disorders may lead to improper tooth development and frequent severe caries in patients during/after antineoplastic treatment and to a more frequent improper tooth development in patients undergoing chemotherapy during odontogenesis. However, the causes of these abnormalities remain unknown; there are no studies on the impact of antineoplastic treatment and its complications on the chemical composition of mineralised teeth. To compare the chemical composition of mineralised teeth extracted due to complicated caries in children after chemotherapy, and of teeth extracted due to orthodontic treatment in generally healthy children. The treatment group included five teeth extracted due to complicated caries in children after antineoplastic treatment. The control group included five teeth extracted due to orthodontic treatment in generally healthy children. The chemical composition of enamel, dentine, cementum, interior of the canal, and enamel abnormalities in teeth extracted from patients after chemotherapy and in generally healthy patients were assessed with energy-dispersive X-ray spectroscopy. Results were analysed statistically. The magnesium (Mg) and zinc (Zn) mass contents in the enamel of patients after chemotherapy increased and so did the calcium (Ca) to phosphorus (P) ratio when compared to controls. Areas with abnormal enamel in patients after chemotherapy had lower concentrations of Ca and P, and higher concentrations of trace elements (Mg, Cl, and Na). The levels of the assessed elements in dentine, cementum, and inside the canal were similar in both groups of teeth.

The impact on bone tissues of immediate implant-supported mandibular overdentures with cusped and cuspless teeth

OpenAIRE

Khalid A. Arafa

2016-01-01

Objectives: To examine the effects on bone tissues of immediate implant-supported mandibular overdentures with cusped or cuspless teeth. Methods: A randomized controlled trial was conducted at the Dental Clinic, Faculty of Dentistry, Al-Azhar University, Assiut Branch, Egypt, over a 12-month period from September 2013 to September 2014. Twenty patients were treated with immediate implant-supported overdentures: one group received overdentures with cusped teeth, and the other group receive...

Manipulation of Fgf and Bmp signaling in teleost fishes suggests potential pathways for the evolutionary origin of multicuspid teeth.

Science.gov (United States)

Jackman, William R; Davies, Shelby H; Lyons, David B; Stauder, Caitlin K; Denton-Schneider, Benjamin R; Jowdry, Andrea; Aigler, Sharon R; Vogel, Scott A; Stock, David W

2013-01-01

Teeth with two or more cusps have arisen independently from an ancestral unicuspid condition in a variety of vertebrate lineages, including sharks, teleost fishes, amphibians, lizards, and mammals. One potential explanation for the repeated origins of multicuspid teeth is the existence of multiple adaptive pathways leading to them, as suggested by their different uses in these lineages. Another is that the addition of cusps required only minor changes in genetic pathways regulating tooth development. Here we provide support for the latter hypothesis by demonstrating that manipulation of the levels of Fibroblast growth factor (Fgf) or Bone morphogenetic protein (Bmp) signaling produces bicuspid teeth in the zebrafish (Danio rerio), a species lacking multicuspid teeth in its ancestry. The generality of these results for teleosts is suggested by the conversion of unicuspid pharyngeal teeth into bicuspid teeth by similar manipulations of the Mexican Tetra (Astyanax mexicanus). That these manipulations also produced supernumerary teeth in both species supports previous suggestions of similarities in the molecular control of tooth and cusp number. We conclude that despite their apparent complexity, the evolutionary origin of multicuspid teeth is positively constrained, likely requiring only slight modifications of a pre-existing mechanism for patterning the number and spacing of individual teeth. © 2013 Wiley Periodicals, Inc.

Teeth re-whitening effect of strawberry juice on coffee stained teeth

OpenAIRE

Annisya Pramesti; Tadeus Arufan Jasrin; Opik Taofik Hidayat

2018-01-01

Many people favor coffee. However, regarding health and aesthetic dentistry, coffee gives a negative effect. Tanin in coffee causes a brown stain on the tooth surface. Therefore, in aesthetic dental care, teeth whitening has become popular matter. One of the natural ingredients used for teeth whitening treatment is strawberry. The purpose of this study was to obtained data regarding the effect of strawberry juice on the re-whitening process of the coffee-stained tooth enamel surface. This stu...

Iron deposition in modern and archaeological teeth

Energy Technology Data Exchange (ETDEWEB)

Williams, A.-M.M., E-mail: AnneMarie.Williams@utas.edu.au [School of Medicine, Private Bag 34, University of Tasmania, Hobart 7001 (Australia); Siegele, R. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)

2014-09-15

Iron surface concentrations and profile maps were measured on the enamel of archaeological and modern teeth to determine how iron is deposited in tooth enamel and if it was affected by the post-mortem environment. Teeth from Australian children who died in the second half of the 19th century were compared with contemporary teeth extracted for orthodontic purposes. Surface analysis of the teeth was performed using the 3 MV Van Der Graff Accelerator at The Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, Australia. A small sample of teeth were then cut in the mid sagittal plane and analysed using ANSTO High Energy Heavy Ion Microprobe. Maps and linear profiles were produced showing the distribution of iron across the enamel. Results show that both the levels and distribution of iron in archaeological teeth is quite different to contemporary teeth, raising the suggestion that iron has been significantly altered by the post-mortem environment.

Iron deposition in modern and archaeological teeth

International Nuclear Information System (INIS)

Williams, A.-M.M.; Siegele, R.

2014-01-01

Iron surface concentrations and profile maps were measured on the enamel of archaeological and modern teeth to determine how iron is deposited in tooth enamel and if it was affected by the post-mortem environment. Teeth from Australian children who died in the second half of the 19th century were compared with contemporary teeth extracted for orthodontic purposes. Surface analysis of the teeth was performed using the 3 MV Van Der Graff Accelerator at The Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, Australia. A small sample of teeth were then cut in the mid sagittal plane and analysed using ANSTO High Energy Heavy Ion Microprobe. Maps and linear profiles were produced showing the distribution of iron across the enamel. Results show that both the levels and distribution of iron in archaeological teeth is quite different to contemporary teeth, raising the suggestion that iron has been significantly altered by the post-mortem environment

Quantifying the impact of µCT-scanning of human fossil teeth on ESR age results.

Science.gov (United States)

Duval, Mathieu; Martín-Francés, Laura

2017-05-01

Fossil human teeth are nowadays systematically CT-scanned by palaeoanthropologists prior to any further analysis. It has been recently demonstrated that this noninvasive technique has, in most cases, virtually no influence on ancient DNA preservation. However, it may have nevertheless an impact on other techniques, like Electron Spin Resonance (ESR) dating, by artificially ageing the apparent age of the sample. To evaluate this impact, we µCT-scanned several modern enamel fragments following the standard analytical procedures employed by the Dental Anthropology Group at CENIEH, Spain, and then performed ESR dose reconstruction for each of them. The results of our experiment demonstrate that the systematic high-resolution µCT-scanning of fossil hominin remains introduces a nonnegligible X-ray dose into the tooth enamel, equivalent to 15-30 Gy depending on the parameters used. This dose may be multiplied by a factor of ∼8 if no metallic filter is used. However, this dose estimate cannot be universally extrapolated to any µCT-scan experiment but has instead to be specifically assessed for each device and set of parameters employed. The impact on the ESR age results is directly dependent on the magnitude of the geological dose measured in fossil enamel but could potentially lead to an age overestimation up to 40% in case of Late Pleistocene samples, if not taken into consideration. © 2017 Wiley Periodicals, Inc.

Multivariate analyses of small theropod dinosaur teeth and implications for paleoecological turnover through time.

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Derek W Larson

Full Text Available Isolated small theropod teeth are abundant in vertebrate microfossil assemblages, and are frequently used in studies of species diversity in ancient ecosystems. However, determining the taxonomic affinities of these teeth is problematic due to an absence of associated diagnostic skeletal material. Species such as Dromaeosaurus albertensis, Richardoestesia gilmorei, and Saurornitholestes langstoni are known from skeletal remains that have been recovered exclusively from the Dinosaur Park Formation (Campanian. It is therefore likely that teeth from different formations widely disparate in age or geographic position are not referable to these species. Tooth taxa without any associated skeletal material, such as Paronychodon lacustris and Richardoestesia isosceles, have also been identified from multiple localities of disparate ages throughout the Late Cretaceous. To address this problem, a dataset of measurements of 1183 small theropod teeth (the most specimen-rich theropod tooth dataset ever constructed from North America ranging in age from Santonian through Maastrichtian were analyzed using multivariate statistical methods: canonical variate analysis, pairwise discriminant function analysis, and multivariate analysis of variance. The results indicate that teeth referred to the same taxon from different formations are often quantitatively distinct. In contrast, isolated teeth found in time equivalent formations are not quantitatively distinguishable from each other. These results support the hypothesis that small theropod taxa, like other dinosaurs in the Late Cretaceous, tend to be exclusive to discrete host formations. The methods outlined have great potential for future studies of isolated teeth worldwide, and may be the most useful non-destructive technique known of extracting the most data possible from isolated and fragmentary specimens. The ability to accurately assess species diversity and turnover through time based on isolated teeth

Multivariate Analyses of Small Theropod Dinosaur Teeth and Implications for Paleoecological Turnover through Time

Science.gov (United States)

Larson, Derek W.; Currie, Philip J.

2013-01-01

Isolated small theropod teeth are abundant in vertebrate microfossil assemblages, and are frequently used in studies of species diversity in ancient ecosystems. However, determining the taxonomic affinities of these teeth is problematic due to an absence of associated diagnostic skeletal material. Species such as Dromaeosaurus albertensis, Richardoestesia gilmorei, and Saurornitholestes langstoni are known from skeletal remains that have been recovered exclusively from the Dinosaur Park Formation (Campanian). It is therefore likely that teeth from different formations widely disparate in age or geographic position are not referable to these species. Tooth taxa without any associated skeletal material, such as Paronychodon lacustris and Richardoestesia isosceles, have also been identified from multiple localities of disparate ages throughout the Late Cretaceous. To address this problem, a dataset of measurements of 1183 small theropod teeth (the most specimen-rich theropod tooth dataset ever constructed) from North America ranging in age from Santonian through Maastrichtian were analyzed using multivariate statistical methods: canonical variate analysis, pairwise discriminant function analysis, and multivariate analysis of variance. The results indicate that teeth referred to the same taxon from different formations are often quantitatively distinct. In contrast, isolated teeth found in time equivalent formations are not quantitatively distinguishable from each other. These results support the hypothesis that small theropod taxa, like other dinosaurs in the Late Cretaceous, tend to be exclusive to discrete host formations. The methods outlined have great potential for future studies of isolated teeth worldwide, and may be the most useful non-destructive technique known of extracting the most data possible from isolated and fragmentary specimens. The ability to accurately assess species diversity and turnover through time based on isolated teeth will help illuminate

Gardner syndrome associated with multiple osteomas, intestinal polyposis, and epidermoid cysts

Energy Technology Data Exchange (ETDEWEB)

Koh, Kwang Joon; Park, Ha Na; Kim, Kyoung A [Dept. of Oral and Maxillofacial Radiology, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju (Korea, Republic of)

2016-12-15

Gardner syndrome is known as a variant of familial adenomatous polyposis. This syndrome is characterized by multiple intestinal polyposes, osteomas, and epidermoid cysts. In addition, dental abnormalities include an increased frequency of multiple odontomas, as well as supernumerary and impacted teeth. The authors report the case of a 7-year-old male patient with Gardner syndrome. Radiographic findings revealed multiple osteomas in both sides of the maxilla, multiple diffuse enostoses in both jaws, and a complex odontoma in the left mandibular body. Two years later, multiple epidermoid cysts on the scalp were found. Since this patient was suspected to have Gardner syndrome, the authors recommended gastrointestinal endoscopy to check for intestinal polyposis. Gastrointestinal endoscopic examination revealed multiple polyposes in the upper gastrointestinal tract and fundus of the stomach. As a result, the final diagnosis was Gardner syndrome.

A New Multi-Ingredient Recipe for the Treatment of Localized Advanced Periodontal Disease following the Surgical Removal of Impacted Wisdom Teeth

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Nabil Khzam

2016-01-01

Full Text Available Periodontal disease is a chronic inflammation of the tooth supporting structures. It leads to bone and attachment loss which is irreversible. Extraction of horizontally impacted lower third molar (L3M teeth may result in localized periodontal pockets at the distal aspect of the adjacent lower second molars (L2M. We present a case of a 21-year-old male who suffered from a swelling and pain around his lower right second molar following surgical removal of a mesioangular impacted lower right third molar. We showed that oral hygiene measures, surgical access, mixture of autogenous and synthetic bone graft, and guided tissue regeneration (GTR were enough to control the problem.

90Sr specific activity of teeth of abandoned cattle after the Fukushima accident - teeth as an indicator of environmental pollution.

Science.gov (United States)

Koarai, Kazuma; Kino, Yasushi; Takahashi, Atsushi; Suzuki, Toshihiko; Shimizu, Yoshinaka; Chiba, Mirei; Osaka, Ken; Sasaki, Keiichi; Urushihara, Yusuke; Fukuda, Tomokazu; Isogai, Emiko; Yamashiro, Hideaki; Oka, Toshitaka; Sekine, Tsutomu; Fukumoto, Manabu; Shinoda, Hisashi

2018-03-01

90 Sr specific activity in the teeth of young cattle that were abandoned in Kawauchi village and Okuma town located in the former evacuation areas of the Fukushima-Daiichi Nuclear Power Plant (FNPP) accident were measured. Additionally, specific activity in contaminated surface soils sampled from the same area was measured. (1) All cattle teeth examined were contaminated with 90 Sr. The specific activity, however, varied depending on the developmental stage of the teeth during the FNPP accident; teeth that had started development before the accident exhibited comparatively lower values, while teeth developed mainly after the accident showed higher values. (2) Values of 90 Sr-specific activity in teeth formed after the FNPP accident were higher than those of the bulk soil but similar to those in the exchangeable fraction (water and CH 3 COONH 4 soluble fractions) of the soil. The findings suggest that 90 Sr was incorporated into the teeth during the process of development, and that 90 Sr in the soluble and/or leachable fractions of the soil might migrate into teeth and contribute to the amount of 90 Sr in the teeth. Thus, the concentration of 90 Sr in teeth formed after the FNPP accident might reflect the extent of 90 Sr pollution in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple Unerupted Permanent Teeth Associated with Noonan ...

African Journals Online (AJOL)

[2] Oral findings in patients with NS include a high arched palate ... the atypical dental anomalies such as multiple unerupted permanent ... clinical features in a child with NS. .... Disabilities, Centers for Disease Control and Prevention (CDC).

Mothers Perception of Teething in Children

African Journals Online (AJOL)

TNHJOURNALPH

includes blistering, bleeding, placing leeches on the gum, applying cautery to the back of the head and lancing- a method where lancet was used to cut the gum in other for the teeth to appear.7 1t was thought that failure of the teeth to appear was due to lack of a pathway and that this was the cause of death from teething,.

An indirect veneer technique for simple and esthetic treatment of anterior hypoplastic teeth

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Amit Khatri

2010-01-01

Full Text Available This study describes a technique for treating anterior hypoplastic teeth using indirect nanocomposite veneer restoration. The prime advantage of an indirect veneer technique is that it provides an esthetic and conservative result. One of the most frequent reasons that patients seek dental care is discolored anterior teeth. Although treatment options such as removal of surface stains, bleaching, microabrasion or macroabrasion, veneering, and placement of porcelain crowns are available, conservative approach such as veneer preserves the natural tooth as much as possible. Full veneers are recommended for the restoration of localized defects or areas of intrinsic discoloration, which are caused by deeper internal stains or enamel defects. Indirectly fabricated veneers are much less sensitive compared to a operator′s technique and if multiple teeth are to be veneered, indirect veneers can be usually placed much more expeditiously. Indirect veneers last much longer than the direct veneers. Therefore, indirectly fabricated veneers are more advantageous than directly fabricated veneers in many cases.

FT-Raman spectroscopy, µ-EDXRF spectrometry, and microhardness analysis of the dentin of primary and permanent teeth.

Science.gov (United States)

Torres, Carolina Paes; Miranda Gomes-Silva, Jaciara; Menezes-Oliveira, Maria Angélica Hueb; Silva Soares, Luís Eduardo; Palma-Dibb, Regina Guenka; Borsatto, Maria Cristina

2018-05-01

The chemical compositions (organic and inorganic contents) and mechanical behaviors of the dentin of permanent and deciduous teeth were analyzed and compared using X-ray fluorescence spectrometry (µ-EDXRF) Fourier transform Raman spectroscopy (FT-Raman) and a microhardness test (HD). Healthy fresh human primary and permanent molars (n = 10) were selected, The buccal surfaces facing upwards were stabilized in an acrylic plate, flattened, polished, and submitted to the µ-EDXRF, FT-Raman, and HD analysis. The results of the analysis were subjected to ANOVAs and Mann-Whitney U/Student's t multiple comparisons tests. The data showed similar values for the dentin of the primary and permanent teeth in P content, organic content (amide I peak), inorganic content ( PO43- - 430 and 590), and microhardness, Nevertheless, Ca content and Ca/P weight ratio were higher, and the CO32- peak was lower in the dentin of the permanent teeth compared to primary teeth. It be concluded that despite permanent teeth showed more Ca element, both substrates showed similar behavior of chemical and physical properties. © 2018 Wiley Periodicals, Inc.

[Current situation of clinical research on impacted premolars].

Science.gov (United States)

Liu, Ran-Ran; Tian, Jun

2018-04-01

Teeth impaction is a common developmental malformation in oral diseases. Impacted teeth are usually the canines, third molar, central incisors, premolars, and second molars. The prevalence of impaction of maxillary canines and mandibular wisdom teeth is higher than that of other teeth. Most recent studies have focused on the canines and third molars, but research on impacted premolars is limited. In clinical practice, the majority of orthodontic patients require premolar extraction. Thus, impacted premolars play important roles in orthodontic design and prognosis. This article provides an overview of recent research on impacted premolars and summarizes epidemiological features, localizations, and treatments, with the aim of guiding practitioners on orthodontic design and therapy.

Investigation of 16% carbamide-peroxide on the structure and properties and effect return enamel staining teeth whitening after their

OpenAIRE

Matvijenko Vladimir; Živković M.; Videnović G.; Kostić-Šubarić Lj.; Živković D.; Perić D.; Jovanović R.

2015-01-01

The most tooth whitening is a procedure that removes stains and various discolorations of tooth surface. Discoloration of teeth may be endogenous and exogenous nature. The aim of this study was to investigate the impact of bleaching combined with daily use of drinks that cause tooth discoloration. Evaluated the changes in surface structure of enamel, and changes in hardness after bleaching. Were 20 extracted teeth. The teeth are marked with longitudinal lines halves (medial vestibular and dis...

Concrescent triplets involving primary anterior teeth

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Urvashi Sharma

2013-01-01

Full Text Available Odontogenesis is a complex process wherein more than 200 genes are known to play a significant role in tooth development. An imbalance can lead to an abnormality in the number, size, shape or structure of the developing tooth/teeth. The presence of an extra dental lamina forms a supernumerary tooth. The supernumerary teeth are of two types: A rudimentary tooth where the supernumerary tooth does not resemble any tooth in the normal series or a supplemental tooth in which this anomalous tooth resembles one in the normal series. It is also very rare to encounter triple teeth in primary dentition. The union of these teeth may be through fusion, gemination, concrescence or a combination of fusion and gemination. Presented is a rare case of concrescence involving maxillary deciduous incisors and a supplemental tooth in a 7-year-old boy. The differential diagnosis, etiology, and complications of primary anterior triple teeth are discussed.

Mouth and Teeth (For Parents)

Science.gov (United States)

... the teeth are subject to disease. A common periodontal disease is gingivitis — inflammation of the gums characterized by redness, swelling, and sometimes bleeding. The accumulation of tartar (a hardened film of food particles and bacteria that builds up on teeth) usually causes this ...

ELECTRIC PULP TEST OF TEETH WITH PERIODONTAL DISEASE.

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Tsonko Uzunov

2014-10-01

Full Text Available Purpose: The aim of the research is to investigate the change in pulp vitality of teeth with periodontal disease using electric pulp tester (EPT. Methods: Subjected to observation were 108 patients with chronic periodontitis. Vitality of 805 teeth with periodontal pocket depth greater than 4 mm was studied by EPT. The research was conducted with EPT "Yonovit ". Results: The highest percentage of surveyed teeth (68.4% respond to the norm when they are tested with EPT – values between 3 μA and 10 μA . Teeth that respond to EPT with values ​​below 3 μA and between 35-100 μA are relatively equal - respectively 4.3% and 3.3%. With increased threshold of irritation – 10-35 μA react 23.4% of teeth. Small number of teeth have threshold of irritation over 100 μA - 0.6%. Conclusion: The value of EPT among periodontal damaged teeth depends on many factors - patient's age, extent of periodontal affect, group affiliation of teeth, etc.

Clinical Characteristics of Abutment Teeth with Gingival Discoloration.

Science.gov (United States)

Ristic, Ljubisa; Dakovic, Dragana; Postic, Srdjan; Lazic, Zoran; Bacevic, Miljana; Vucevic, Dragana

2017-04-06

The grey-bluish discoloration of gingiva (known as "amalgam tattoo") does not appear only in the presence of amalgam restorations. It may also be seen in cases of teeth restored with cast dowels and porcelain-fused-to-metal (PFM) restorations. The aim of this article was to determine the clinical characteristics of abutment teeth with gingival discoloration. This research was conducted on 25 patients referred for cast dowel and PFM restorations. These restorations were manufactured from Ni-Cr alloys. Ninety days after cementing the fixed prosthodontic restorations, the abutment teeth (n = 61) were divided into a group with gingival discoloration (GD) (n = 25) and without gingival discoloration (NGD) (n = 36). The control group (CG) comprised the contralateral teeth (n = 61). Plaque index, gingival index, clinical attachment level, and probing depth were assessed before fabrication and also 90 days after cementation of the PFM restorations. The gingival index, clinical attachment level, and probing depths of the abutment teeth that had GD were statistically higher before restoration, in comparison with the abutment teeth in the NGD and control groups. Ninety days after cementation, the abutment teeth with GD had significantly lower gingival indexes and probing depths, compared to the abutment teeth in the NGD group. Both abutment teeth groups (GD and NGD) had significantly higher values of clinical attachment levels when compared to the control group. There were no statistically significant differences in plaque index values between the study groups. The results of this study indicated that impairment of periodontal status of abutment teeth seemed to be related to the presence of gingival discolorations. Therefore, fabrication of fixed prosthodontic restorations requires careful planning and abutment teeth preparation to minimize the occurrence of gingival discolorations. With careful preparation of abutment teeth for cast dowels and crown restorations it may be

Predictable management of cracked teeth with reversible pulpitis.

Science.gov (United States)

Abbott, P; Leow, N

2009-12-01

The aims of this study were to assess symptoms and signs caused by cracks in teeth and to assess a conservative management protocol. The symptoms and signs of 100 consecutive teeth that had reversible pulpitis associated with cracks were compared to findings from other reports. Teeth were managed with a conservative protocol which involved removal of cracks, caries and restorations, followed by placement of a sedative lining and interim restoration unless there were pulp exposures or insufficient tooth structure remaining. Teeth were monitored for pulp healing after three months and for up to five years. Eighty teeth did not require endodontic treatment. One tooth had an uncertain pulp status at review appointments. Fifteen teeth required endodontic treatment at the initial appointment because of carious pulp exposures (4 teeth), cracks extending into the pulp (2), and posts required (9). Four other teeth required endodontic treatment later following conservative pulp treatment due to continued pulpitis under the temporary restoration (1), pulpitis after core restoration (2), and pulp necrosis diagnosed at the review (1). Provided there is an accurate diagnosis of the pulp status and its cause, teeth with reversible pulpitis due to cracks can be treated conservatively without endodontic treatment in about 80 per cent of cases.

Energy absorption build-up factors in teeth

International Nuclear Information System (INIS)

Manjunatha, H.C.; Rudraswamy, B.

2012-01-01

Geometric progression fitting method has been used to compute energy absorption build-up factor of teeth [enamel outer surface, enamel middle, enamel dentin junction towards enamel, enamel dentin junction towards dentin, dentin middle and dentin inner surface] for wide energy range (0.015-15 MeV) up to the penetration depth of 40 mean free path. The dependence of energy absorption build-up factor on incident photon energy, penetration depth, electron density and effective atomic number has also been studied. The energy absorption build-up factors increases with the penetration depth and electron density of teeth. So that the degree of violation of Lambert-Beer (I = I 0 e -μt ) law is less for least penetration depth and electron density. The energy absorption build-up factors for different regions of teeth are not same hence the energy absorbed by the different regions of teeth is not uniform which depends on the composition of the medium. The relative dose of gamma in different regions of teeth is also estimated. Dosimetric implication of energy absorption build-up factor in teeth has also been discussed. The estimated absorption build up factors in different regions of teeth may be useful in the electron spin resonance dosimetry. (author)

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.

Characteristics of Teeth: A Review of Size, Shape, Composition, and Appearance of Maxillary Anterior Teeth.

Science.gov (United States)

McGowan, Steve

2016-03-01

Although digital technologies play an increasingly integral role in dentistry, there remains a need for dental professionals to understand the fundamentals of tooth anatomy, form, occlusion, and color science. In this article, the size, shape, composition, and appearance of maxillary anterior teeth will be discussed from esthetic and functional perspectives. A total of 600 extracted maxillary incisors were studied: 200 each of central incisors, lateral incisors, and cuspids. The purpose of the article is to exhibit and discuss factors that make teeth unique and diverse. Understanding these aspects of teeth aids dental professionals in more effectively creating realistic and highly esthetic restorations for patients.

[Conservative treatment of deciduous teeth--a review].

Science.gov (United States)

Magnusson, B

1976-06-01

In all countries with a lack of manpower in dentistry, there is an unfortunate tendency to leave the primary teeth without proper conservative treatment. In addition to toothaches and poor esthetics, a neglected care of the primary dentition may result in several other untoward effects. Decayed deciduous teeth may cause such a discomfort during tooth-brushing that the child is prevented from learning good oral hygiene habits. With bad primary molars the child cannot chew properly, and may have to choose soft and often cariogenic food. When the permanent teeth erupt among the decayed deciduous teeth, there will be a greater chance for them to have carious attacks as well. Premature loss of primary molars may lead to malocclusion. It must also be kept in mind that the treatment of badly decayed teeth, including necessary extractions, may be difficult. This may cause fear of dental treatment. On the basis of current Swedish philosophies of treatment the author surveys various conservative procedures for deciduous teeth-amalgam therapy, stainless steel crowns, composites and disking.

Anatomical and histological characteristics of teeth in agouti (Dasyprocta prymnolopha Wagler, 1831

Directory of Open Access Journals (Sweden)

Daiane C. Baia da Silva

2013-12-01

Full Text Available The agouti species Dasyprocta prymnolopha (D. prymnolopha is a medium-sized rodent, diurnal, and characteristic of northeastern Brazil, south of the Amazon. Several studies have been made on these rodents. However, there is a lack of analysis of masticatory system, in particular morphology of the teeth. Thus, this research seeks to describe anatomical and histological aspects of the agouti teeth. For this purpose, we used adult agouti, in which measurements and descriptions of teeth and dental tissues were made. It was observed that the dental arch of D. prymnolopha comprises of twenty teeth, evenly distributed in the upper and lower arch, being inferior teeth larger than their corresponding higher. The incisors are larger, and between the posterior premolars and molars, there is a gradual increase in length in the anterior-posterior arch. In microscopic examination, a prismatic appearance was observed consisting of enamel prisms arranged in different directions, behind the enamel and dentin with standard tubular dentinal tubules with variable diameter and far between, also showing a sinuous path from the inner portion to the junction with more superficial enamel. Morphological analysis of dental tissues showed that an enamel with structural organization adapted to the act of chewing and high impact dentin compatible with standard tubular function resilience and mechanical damping of masticatory forces, as found in larger animals, confirming the understanding of eating habits that define much of its ecological functions within the ecosystem they inhabit.

Microprobe analysis of teeth by synchrotron radiation: environmental contamination

International Nuclear Information System (INIS)

Pinheiro, T.; Carvalho, M.L.; Casaca, C.; Barreiros, M.A.; Cunha, A.S.; Chevallier, P.

1999-01-01

An X-ray fluorescence set-up with microprobe capabilities, installed at the Laboratoire pour l'Utilisation du Rayonnement Electromagnetique (LURE) synchrotron (France) was used for elemental determination in teeth. To evaluate the influence of living habits in dental elemental composition nine teeth collected post-mortem were analysed, five from a miner and four from a fisherman. All teeth from the fisherman were healthy. From the miner some teeth were carious and one of them was filled with metallic amalgam. Teeth were sliced under the vertical plane and each slice was scanned from the root to the enamel for elemental profile determination. The synchrotron microprobe resolution was of 100 μm and incident photons of 18 keV energy were used. The elemental concentration values found suggest heterogeneity of the teeth material. Moreover, the distinct profiles for Mn, Sr, Br and Pb were found when teeth from the miner and from the fisherman are compared which can be associated with dietary habits and environmental influence. Higher concentrations of Mn and Sr were found for the fisherman teeth. In addition, Br was only observed in this group of teeth. Pb levels are higher for the miner teeth in particular for dentine regions. The influence of amalgam, such as, increase of Zn and Hg contents in the teeth material, is only noticed for the immediate surroundings of the treated cavity

Tips for splinting traumatised teeth

LENUS (Irish Health Repository)

Leith, Rona

2017-10-01

A splint is required when teeth are mobile or need to be repositioned following a traumatic injury. The aim of splinting is to stabilise the injured tooth and maintain its position throughout the splinting period, improve function and provide comfort. Current best practice guidelines from the International Association for Dental Traumatology (IADT) recommend splinting for luxated, avulsed, root fractured and traumatically loosened permanent teeth.1,2 Splinting of primary teeth is usually not feasible. In general, the prognosis of a traumatised tooth is determined by the type of injury rather than the type of splint.3 However, correct splinting is important to maximise healing of the soft and hard tissues, and prevent further injury.1-6

Tips for splinting traumatised teeth

LENUS (Irish Health Repository)

Leith, Rona

2017-11-01

A splint is required when teeth are mobile or need to be repositioned following a traumatic injury. The aim of splinting is to stabilise the injured tooth and maintain its position throughout the splinting period, improve function and provide comfort. Current best practice guidelines from the International Association for Dental Traumatology (IADT) recommend splinting for luxated, avulsed, root fractured and traumatically loosened permanent teeth.1,2 Splinting of primary teeth is usually not feasible. In general, the prognosis of a traumatised tooth is determined by the type of injury rather than the type of splint.3 However, correct splinting is important to maximise healing of the soft and hard tissues, and prevent further injury.1

Is it better to leave or restore carious deciduous molar teeth? A preliminary study.

Science.gov (United States)

Tickle, M; Milsom, K; Kennedy, A

1999-10-01

The objective of this study was to compare the extraction and exfoliation experience of filled and unfilled carious deciduous molar teeth. The study was carried out in 1997 in four general dental practices in south Cheshire, UK and involved a longitudinal retrospective review of case notes. A quota sample of 20 case notes of children from each practice was selected according to strict criteria. Subjects had to: Have had experience of approximal caries in one or more of the deciduous molar teeth. Have a date of birth between 1st January 1984 and 31st December 1985. Be a regular attender and in continuous contact with the practice. Data were collected on a common data abstraction form. Variables measured included: Base-line dmft. Site and number of filled teeth. Site and number of unfilled carious teeth. Number of courses of antibiotics. Site and number of pulp therapies. Site, number, method (local or general anaesthetic) of extractions. Reasons for extraction. All teeth not recorded as being extracted were assumed to have exfoliated. In addition, information was collected on the dentists' treatment philosophies. A series of group discussions revealed that the four dentists fitted into two groups according to treatment philosophies; two dentists shared a philosophy of minimal intervention, the other two shared the same views of treating more radically. There was no significant difference between the proportion of filled teeth and the proportion of carious unfilled teeth that were extracted (chi-square 0.05 P = 0.83). A logistic regression showed that for each course of antibiotics administered the odds of having an extraction was multiplied by 5.5 and children who were patients of the interventionist dentists were five times more likely to have an extraction than patients of non-interventionist dentists. Although the study was preliminary in nature no clear benefit could be found in filling deciduous molar teeth against leaving carious teeth unfilled, if avoidance

Multiple jaw cysts not associated with basal cell nevus syndrome

International Nuclear Information System (INIS)

Yoon, Suk Ja; Kang, Byung Cheol

2003-01-01

We present two cases of multiple jaw cysts not associated with basal cell nevus syndrome. Case 1 : a nine year-old boy visited CNU Hospital for orthodontic treatment and his radiographs showed cystic lesions surrounding the crowns of teeth 13 and 17 respectively, which were diagnosed as dentigerous cysts. Subsequently, two more cysts were found on his follow-up radiographs in 12 and 15 months. The two cysts were determined to be odontogenic keratocysts. The boy had no skeletal abnormalities and no skin lesions associated with basal cell nevus syndrome. Case 2: a fifty-eight year old man had three impacted third molars with pericoronal radiolucencies, which were diagnosed as dentigerous cysts. He had no additional abnormalities associated with basal cell nevus syndrome. Multiple jaw cysts can occur at any age, and periodic radiographic surveillance may be needed for any cases of impacted tooth.

Multiple jaw cysts not associated with basal cell nevus syndrome

Energy Technology Data Exchange (ETDEWEB)

Yoon, Suk Ja; Kang, Byung Cheol [Chonnam National University College of Medicine, Kwangju (Korea, Republic of)

2003-09-15

We present two cases of multiple jaw cysts not associated with basal cell nevus syndrome. Case 1 : a nine year-old boy visited CNU Hospital for orthodontic treatment and his radiographs showed cystic lesions surrounding the crowns of teeth 13 and 17 respectively, which were diagnosed as dentigerous cysts. Subsequently, two more cysts were found on his follow-up radiographs in 12 and 15 months. The two cysts were determined to be odontogenic keratocysts. The boy had no skeletal abnormalities and no skin lesions associated with basal cell nevus syndrome. Case 2: a fifty-eight year old man had three impacted third molars with pericoronal radiolucencies, which were diagnosed as dentigerous cysts. He had no additional abnormalities associated with basal cell nevus syndrome. Multiple jaw cysts can occur at any age, and periodic radiographic surveillance may be needed for any cases of impacted tooth.

The gothic arch tracing and the upper canine teeth as guides in the positioning of upper posterior teeth.

Science.gov (United States)

el-Gheriani, A S; Davies, A L; Winstanley, R B

1989-09-01

The relationship between the position of the buccal cusps of the natural upper posterior teeth and the distance between the lateral arms of the Gothic arch tracing or the distance between the upper canine teeth has been found to be constant to within +/- 2 mm. This may be of value when setting up artificial teeth for denture patients, enabling them to be positioned close to the natural predecessors.

Factors influencing the presence of interproximal dental papillae between maxillary anterior teeth.

Science.gov (United States)

Chen, Min-Chieh; Liao, Yu-Fang; Chan, Chiu-Po; Ku, Yen-Chen; Pan, Whei-Lin; Tu, Yu-Kang

2010-02-01

The presence of interdental papillae in the maxillary anterior region plays a key esthetic role. The aim of this study is to investigate the impact of demographic variables, such as gender and ages, and radiographic measurements of interdental area anatomy on the presence of interdental papillae. Periapical radiographs of 102 interdental papillae between maxillary anterior teeth were obtained in 30 adults who had fully erupted permanent dentition, healthy gingiva, and well-aligned maxillary anterior teeth. A radiopaque material was placed on the tip of the interdental papilla and the mucogingival junction. Radiographic measurements of tooth shape, alveolar bone level, and interdental space anatomy were undertaken using computer software. When each factor was evaluated individually, the shorter the distance between the contact bone and alveolar bone crest, the shorter the distance between two adjacent teeth, and the smaller the embrasure area, the more likely interdental papillae were present. Interdental papillae were more likely to be present between teeth with a rectangular tooth form. When all factors were evaluated together, the presence of interdental papillae was only significantly related to the distance from the contact point to the bone crest (P = 0.038). In the anterior maxillary region, the shorter the distance between the contact point to the bone crest, the more likely interdental papillae were present.

Orthodontic exposure of multiple lmpactions: a case report.

Science.gov (United States)

Munda-Lacson, Maridin C; Venugopal, Adith

2014-01-01

There are rare cases of impacted permanent central incisors with dilacerations, a dental deformity characterized by pronounced angulations of the longitudinal tooth axis. Impaction of maxillary canines is an orthodontic anomaly that causes facial and dentoalveolar system problems, both functional and esthetic. A combination of surgery and orthodontics is important in bringing impacted teeth to their ideal position in the dental arch. This is a case report of a 10-year-old patient with impacted and dilacerated right central incisor and impacted left maxillary canine, following surgical exposure and appropriate orthodontic traction, the impacted teeth were surgically exposed and aligned into the dental arch.

Posterior teeth occlusion and dysphagia risk in older nursing home residents: a cross-sectional observational study.

Science.gov (United States)

Okabe, Y; Takeuchi, K; Izumi, M; Furuta, M; Takeshita, T; Shibata, Y; Kageyama, S; Ganaha, S; Yamashita, Y

2017-02-01

The total number of natural teeth was related to swallowing function among older adults; however, limited information is available regarding the impact of occluding pairs of teeth on swallowing function. This study aimed to examine the association between posterior teeth occlusion and dysphagia risk in older nursing home residents. This cross-sectional study included 238 residents aged ≥60 years from eight nursing homes in Aso City, Japan. Swallowing function was evaluated using the modified water swallowing test (MWST); the primary outcome was dysphagia risk (MWST score ≤3). Posterior teeth occlusion was assessed using number of functional tooth units (FTUs), determined based on number and location of the remaining natural and artificial teeth on implant-supported, fixed or removable prostheses. Univariate and multivariate logistic regression analyses were performed to examine the association between posterior teeth occlusion and dysphagia risk, adjusted for the covariates of number of natural teeth, demographic characteristics, comorbidities, physical function, body mass index and cognitive function. Of the 238 subjects, 44 (18·5%) were determined to be at risk of dysphagia based on the MWST scores. The odds ratio (OR) of dysphagia risk decreased in subjects with higher total FTUs [OR = 0·92, 95% confidence interval (CI) 0·87-0·98]. After adjusting for covariates, this association remained significant (OR = 0·90, 95% CI 0·84-0·97). Loss of posterior teeth occlusion was independently associated with dysphagia risk in older nursing home residents. Maintaining and restoring posterior teeth occlusion may be an effective measure to prevent dysphagia. © 2016 John Wiley & Sons Ltd.

The creation of virtual teeth with and without tooth pathology for a virtual learning environment in dental education.

Science.gov (United States)

de Boer, I R; Wesselink, P R; Vervoorn, J M

2013-11-01

To describe the development and opportunities for implementation of virtual teeth with and without pathology for use in a virtual learning environment in dental education. The creation of virtual teeth begins by scanning a tooth with a cone beam CT. The resulting scan consists of multiple two-dimensional grey-scale images. The specially designed software program ColorMapEditor connects these two-dimensional images to create a three-dimensional tooth. With this software, any aspect of the tooth can be modified, including its colour, volume, shape and density, resulting in the creation of virtual teeth of any type. This article provides examples of realistic virtual teeth with and without pathology that can be used for dental education. ColorMapEditor offers infinite possibilities to adjust and add options for the optimisation of virtual teeth. Virtual teeth have unlimited availability for dental students, allowing them to practise as often as required. Virtual teeth can be made and adjusted to any shape with any type of pathology. Further developments in software and hardware technology are necessary to refine the ability to colour and shape the interior of the pulp chamber and surface of the tooth to enable not only treatment but also diagnostics and thus create a greater degree of realism. The creation and use of virtual teeth in dental education appears to be feasible but is still in development; it offers many opportunities for the creation of teeth with various pathologies, although an evaluation of its use in dental education is still required. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

THE PAR (PEER ASSESSMENT RATING CALCULATION ON 2 DIMENSIONAL TEETH MODEL IMAGE FOR THE CENTERLINE COMPONENT AND TEETH SEGMENTATION ON THE OCCLUSAL SURFACE TEETH MODEL IMAGE

Directory of Open Access Journals (Sweden)

Hanif Arief Wisesa

2014-08-01

Full Text Available Abstract The PAR (Peer Assessment Rating Index is used by orthodontists around the world to calculate the severeness of a malocclusion. A malocclusion is a dental disease where the teeth are not properly aligned. In Indonesia, the number of malocclusion is relatively high. The occurrence of orthodontics who can treat malocclusion is also low in Indonesia. In 2013, a research is done to create the telehealth monitoring system to provide better treatment of malocclusion in Indonesia. The research is further improved by using different Adaptive Multiple Thresholding methods to segmentate the image. The result will be used to calculate the Centerline component of the PAR Index. The result is a system that could calculate the PAR Index automatically and is compared to the results using manual method.

Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29)

OpenAIRE

Ramp, Melina; Khan, Fary; Misajon, Rose Anne; Pallant, Julie F

2009-01-01

Abstract Background Multiple Sclerosis (MS) is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29) is a disease-specific health-related quality of life (HRQoL) instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS) and psychological (MSIS-29-PSYCH) im...

Behavioral Determinants of Brushing Young Children's Teeth: Implications for Anticipatory Guidance

Science.gov (United States)

Huebner, Colleen E.; Riedy, Christine A.

2010-01-01

Purpose The purposes of this study were to identify parents' motivation, support, and barriers to twice daily tooth-brushing of infants and preschool-age children and to discover new approaches to encourage this important health behavior. Methods Qualitative interviews were conducted with 44 rural parents about tooth-brushing habits and experiences. Results Forty of 44 parents reported that they had begun to brush their child's teeth; 24 (55%) reported brushing twice a day or more. Parents who brushed twice a day, vs less often, were more likely to describe specific skills to overcome barriers; they expressed high self-efficacy and held high self-standards for brushing. Parents who brushed their children's teeth less than twice daily were more likely to: hold false beliefs about the benefits of twice daily tooth-brushing; report little normative pressure or social support for the behavior; have lower self-standards; describe more external constraints; and offer fewer ideas to overcome barriers. Conclusions The findings support an integrative framework in which barriers and support for parents' twice daily brushing of their young children's teeth are multiple and vary among individuals. Knowledge of behavioral determinants specific to individual parents could strengthen anticipatory guidance and recommendations about at-home oral hygiene of young children. PMID:20298653

Detent Force Reduction of a C-Core Linear Flux-Switching Permanent Magnet Machine with Multiple Additional Teeth

Directory of Open Access Journals (Sweden)

Yi Du

2017-03-01

Full Text Available C-core linear flux-switching permanent magnet (PM machines (LFSPMs are attracting more and more attention due to their advantages of simplicity and robustness of the secondary side, high power density and high torque density, in which both PMs and armature windings are housed in the primary side. The primary salient tooth wound with a concentrated winding consists of C-shaped iron core segments between which PMs are sandwiched and the magnetization directions of these PMs are adjacent and alternant in the horizontal direction. On the other hand, the secondary side is composed of a simple iron core with salient teeth so that it is very suitable for long stroke applications. However, the detent force of the C-core LFSPM machine is relatively high and the magnetic circuit is unbalanced due to the end effect. Thus, a new multiple additional tooth which consists of an active and a traditional passive additional tooth, is employed at each end side of the primary in this paper, so that the asymmetry due to end effect can be depressed and the detent force can be reduced by adjusting the passive additional tooth position. By using the finite element method, the characteristics and performances of the proposed machine are analyzed and verified.

Structure, attachment, replacement and growth of teeth in bluefish, Pomatomus saltatrix (Linnaeus, 1776), a teleost with deeply socketed teeth.

Science.gov (United States)

Bemis, William E; Giuliano, Anne; McGuire, Betty

2005-01-01

Tooth replacement poses many questions about development, pattern formation, tooth attachment mechanisms, functional morphology and the evolution of vertebrate dentitions. Although most vertebrate species have polyphyodont dentitions, detailed knowledge of tooth structure and replacement is poor for most groups, particularly actinopterygians. We examined the oral dentition of the bluefish, Pomatomus saltatrix, a pelagic and coastal marine predator, using a sample of 50 individuals. The oral teeth are located on the dentary and premaxillary bones, and we scored each tooth locus in the dentary and premaxillary bones using a four-part functional classification: absent (A), incoming (I), functional (F=fully ankylosed) or eroding (E). The homodont oral teeth of Pomatomus are sharp, deeply socketed and firmly ankylosed to the bone of attachment. Replacement is intraosseus and occurs in alternate tooth loci with long waves of replacement passing from rear to front. The much higher percentage of functional as opposed to eroding teeth suggests that replacement rates are low but that individual teeth are quickly lost once erosion begins. Tooth number increases ontogenetically, ranging from 15-31 dentary teeth and 15-39 premaxillary teeth in the sample studied. Teeth increase in size with every replacement cycle. Remodeling of the attachment bone occurs continuously to accommodate growth. New tooth germs originate from a discontinuous dental lamina and migrate from the lingual (dentary) or labial (premaxillary) epithelium through pores in the bone of attachment into the resorption spaces beneath the existing teeth. Pomatomus shares unique aspects of tooth replacement with barracudas and other scombroids and this supports the interpretation that Pomatomus is more closely related to scombroids than to carangoids.

Neutron activation analysis of manganese in teeth of Japanese adults

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Emiko [Nihon Univ., Tokyo. School of Dentistry

1982-01-01

In an investigation of the manganese (Mn) content of teeth in Japanese adults, neutron activation analysis was carried out of caries-free teeth, carious teeth and unerupted teeth gathered from three different districts of Japan. Regular logarithmic distribution of Mn in the dentin suggested that Mn had not been taken into account as an essential element of the teeth. Results of the study revealed no difference in Mn content among these districts, and between the caries-free teeth and the carious teeth, both in enamel and dentin. The Mn content of the enamel was about two times higher than that of the dentin.

Near-IR imaging of cracks in teeth

Science.gov (United States)

Fried, William A.; Simon, Jacob C.; Lucas, Seth; Chan, Kenneth H.; Darling, Cynthia L.; Staninec, Michal; Fried, Daniel

2014-02-01

Dental enamel is highly transparent at near-IR wavelengths and several studies have shown that these wavelengths are well suited for optical transillumination for the detection and imaging of tooth decay. We hypothesize that these wavelengths are also well suited for imaging cracks in teeth. Extracted teeth with suspected cracks were imaged at several wavelengths in the near-IR from 1300-1700-nm. Extracted teeth were also examined with optical coherence tomography to confirm the existence of suspected cracks. Several teeth of volunteers were also imaged in vivo at 1300-nm to demonstrate clinical potential. In addition we induced cracks in teeth using a carbon dioxide laser and imaged crack formation and propagation in real time using near-IR transillumination. Cracks were clearly visible using near-IR imaging at 1300-nm in both in vitro and in vivo images. Cracks and fractures also interfered with light propagation in the tooth aiding in crack identification and assessment of depth and severity.

PIXE analysis of trace elements in cetacean teeth

International Nuclear Information System (INIS)

Mitani, Yoko; Arai, Nobuaki; Sakamoto, Wataru; Yoshida, Koji

1997-01-01

PIXE was adopted for analysis of trace elements in teeth of two species of cetaceans, sperm whale (Physeter microcephalus) and pantropical spotted dolphin (Stenella attenuata). The analyses were performed along with the growth layer of the teeth, which is formed annually, suitable for age determination. Mn, Fe, Cu, Zu and Sr were detected in the teeth of sperm whale and pantropical spotted dolphin. Among these trace elements, gradual increase was observed for Zn/Ca ratio in the sperm whale's teeth. (author)

Complex aesthetic treatment on anterior maxillary teeth with malposition

Directory of Open Access Journals (Sweden)

Febriastuti Febriastuti

2008-12-01

Full Text Available Background: Complex aesthetic treatment on anterior teeth involves more than one caries tooth with malformed shape and malposition. Purpose: The purpose of this paper is to find the alternative treatment for anterior maxillary teeth with malposition. Case: In this case, a 25 year-old man with a peg shaped teeth and caries on several teeth and malposition can be treated with complex aesthetic treatment. Case management: Endodontic pulpectomy treatment on anterior maxillary teeth and post construction with splint porcelain fused to metal crowns on 11, 12, and 21, 22 to correct the shape and position into normal position. Conclusion: Malformed and malpositioned teeth with caries can be treated with complex aesthetic treatment.

Examination of lead content in school children's teeth

Energy Technology Data Exchange (ETDEWEB)

Yamaga, M; Omori, K; Tozawa, T; Abe, K

1972-11-01

The results of examination on the relationship between air pollution by lead in auto exhaust and lead content of teeth of schoolchildren living in highly polluted, moderately polluted, and nonpolluted areas in Kanagawa Prefecture in 1968 are reported. The specimens were milk teeth which have fallen out and teeth in caries which were pulled out. The 177 specimens were brushed well, washed with distilled water and dried to be wet-calcined. Because of no difference of lead content between boys and girls teeth, the examination was carried on combined specimens. The findings were: (1) lead content was significantly higher in teeth of children in heavily and moderately polluted areas than in those in nonpolluted areas; (2) the lead content by area and by age showed lower values in older children in highly and nonpolluted areas. In general, the lead content of teeth was higher in children living in more polluted areas suggesting the effect of environmental pollution.

What are the longevities of teeth and oral implants?

DEFF Research Database (Denmark)

Holm-Pedersen, Poul; Lang, Niklaus P; Müller, Frauke

2007-01-01

To analyse tooth loss and to evaluate the longevity of healthy teeth and teeth compromised by diseases and influenced by therapy as well as that of oral implants.......To analyse tooth loss and to evaluate the longevity of healthy teeth and teeth compromised by diseases and influenced by therapy as well as that of oral implants....

Prevalence of early loss of primary teeth in 5-10-year-old school children in Chidambaram town.

Science.gov (United States)

Ahamed, S Syed Shaheed; Reddy, Venugopal N; Krishnakumar, R; Mohan, Muthu G; Sugumaran, Durai K; Rao, Arun P

2012-01-01

The premature loss of primary teeth may reduce arch length required for the succeeding tooth and, hence, predisposes crowding, rotation and impaction of the permanent teeth. There are only limited studies carried out about the prevalence of early loss of primary teeth. The present study was performed to evaluate the prevalence of early loss of primary teeth in school children in Chidambaram town in Tamilnadu, India. A total of 1121 school children (561 boys and 560 girls) between 5 and 10 years of age were selected for the study. An experienced examiner performed all clinical examinations under natural light. Data including age and missing tooth was collected. Microsoft Excel/2000 (Microsoft Office XP) data spreadsheet was used and later exported to the Statistical Package for Social Science (SPSS) for Windows (version 10.0). Descriptive statistics was applied and, from the results, chi-square tests were applied at a level of significance of 5% (P loss of primary teeth, but no differences were observed between genders (P > 0.05). The greatest prevalence was found among the 8-year olds (5.08%), and the most commonly missing teeth were the right lower primary first molars (16.82%). It can be concluded that the prevalence of early loss was high and that the lower primary molars were the most commonly missing teeth in the present study.

Straight, white teeth as a social prerogative.

Science.gov (United States)

Khalid, Abeer; Quiñonez, Carlos

2015-06-01

A distinguishing feature of North American society is preoccupation with self-image, as seen in the ritualistic nature of bodily practices aimed at constantly improving the body. Nowhere is this more apparent than in the prevailing fixation with straight, white teeth. While there is an ever-expanding literature on the sociology of body, very little has been written on teeth in this context. Using literature from anthropology, biology, dentistry, sociology and social psychology, this study attempts to answer: (1) Why have straight, white teeth become a beauty ideal in North American society? (2) What is the basis for this ideal? (3) How is this ideal propagated? It demonstrates that dental aesthetic tendencies are biologically, culturally and socially patterned. Concepts from the works of Pierre Bourdieu and Michel Foucault are used to illustrate how straight, white teeth contribute towards reinforcing class differences and how society exercises a disciplinary power on individuals through this ideal. It is concluded that modified teeth are linked to self and identity that are rooted in social structure. Moreover, teeth demonstrate the ways in which class differences are embodied and projected as symbols of social advantage or disadvantage. Implications on professional, public health, sociological and political levels are considered. © 2015 Foundation for the Sociology of Health & Illness.

Orthodontic-surgical treatment of bilateral maxillary canine impaction

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Sumitra

2012-01-01

Full Text Available A 13-year-old female patient reported with the chief complaint of irregular front teeth. She had a skeletal Class III and Angle′s Class I malocclusion with hyperdivergent growth pattern and bilateral impaction of maxillary canines. Surgical exposure of the impacted teeth and orthodontic alignment was planned. The surgical exposure was done by a minimally invasive modified window technique. Orthodontic treatment of impacted canines without causing significant morbidity to the adjacent teeth and periodontium is a challenge. The bilaterally impacted maxillary canines were successfully aligned and leveled. The depth of the gingival sulcus and clinical crown heights of disimpacted teeth were normal post-treatment and after 1 year of retention.

Management of multiple intrusive luxative injuries: A case report with 7-year follow-up

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Seema Thakur

2014-01-01

Full Text Available This report presents a case of severe intrusive luxation of multiple anterior teeth in an 11-year-old girl. The teeth were repositioned successfully by endodontic and orthodontic management. The case was monitored for 7 years. Depending on the severity of the injury, different clinical approaches for treatment of intrusive luxation may be used. Despite the variety of treatment modalities, rehabilitation of intruded teeth is always a challenge and a multidisciplinary approach is important to achieve a successful result. In this case, intruded teeth were endodontically treated with multiple calcium hydroxide dressings and repositioned orthodontically. The follow-up of such cases is very important as the repair process after intrusion is complex. After 7 years, no clinical or radiographic pathology was detected.

External root resorption during orthodontic treatment in root-filled teeth and contralateral teeth with vital pulp: A clinical study of contributing factors.

Science.gov (United States)

Lee, Yun Ju; Lee, Tae Yeon

2016-01-01

There is a lack of research to support the belief that root canal treatment can be considered for stopping or decreasing external apical root resorption (EARR). There is conflicting evidence as to whether root-filled teeth are more or less likely to experience EARR after orthodontic treatment. The purpose of this study was to compare the degree of EARR of root-filled teeth with that of contralateral teeth with vital pulp after fixed orthodontic treatment. The study sample consisted of 35 patients aged 25.23 ± 4.92 years who had at least 1 root-filled tooth before orthodontic treatment. Digital panoramic radiographs of each patient taken before and after orthodontic treatment were used to measure the EARR. The Student t test for matched pairs and the Pearson correlation analysis were applied. The mean EARR values were 0.22 (0.14, 0.35) for root-filled teeth and 0.87 (0.59, 1.31) for contralateral teeth with vital pulp, indicating significantly less EARR for root-filled teeth compared with the contralateral teeth with vital pulp after orthodontic treatment. EARR was influenced by the patient's age, treatment duration, treatment type, and periapical pathosis, but not by tooth type and sex. Root-filled teeth appear to be associated with significantly less EARR than are contralateral teeth with vital pulp. This study suggests that the possible complication of EARR in root-filled teeth may not be an important consideration in orthodontic treatment planning, and root canal treatment can be considered for stopping or decreasing EARR when severe EARR occurs during orthodontic treatment. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

[Root resorption after orthodontic treatment: a study of age factor and prevalence in anterior teeth].

Science.gov (United States)

Tian, Yu-lou; Wang, Kun; Wang, Jing; Liu, Fang; Piao, Mei-ling

2013-04-01

To investigate the impact of age factor on root resorption and the prevalence in anterior teeth during orthodontic treatment. Sixty extraction cases treated with straight wire appliance were divided into adult group and child group, with 30 cases in each group.The panoramic radiographs pre-treatment and post-treatment were examined to measure the degrees of root resorption. A total of 360 anterior teeth in each group were evaluated. SPSS 13.0 software package was applied to perform statistical analysis. There was significant difference in root resorption index before and after treatment(Proot resorption increased remarkably after orthodontic treatment. There was significant difference in the degree of root resorption in two groups (Proot resorption in anterior teeth was: upper central incisors, upper lateral incisors, lower central incisors, lower lateral incisors, upper canines and lower canines. The root resorption in adult patients are more obvious than child patients. The prevalence of root resorption in anterior teeth is different. Moderate or severe root resorption is prone to happen in upper central incisors or lateral incisors in adult patients.

Evaluation of the appreciation of virtual teeth with and without pathology.

Science.gov (United States)

de Boer, I R; Lagerweij, M D; Wesselink, P R; Vervoorn, J M

2015-05-01

Virtual teeth with and without tooth pathology have been developed for use in a virtual learning environment in dental education. The objective of this study was to evaluate the appearance of these virtual teeth for use in dental education and to compare them with contemporary educational models, such as plastic teeth (Frasaco GmbH) and extracted human teeth. Six sets of photographs representing six different teeth were shown to dentists, teachers (dentists) and dental students (bachelor's and master's degree students). Each set consisted of 15 pictures showing five views of the extracted human tooth, the similar virtual tooth and the plastic tooth. The five views represented the mesial, distal, occlusal, buccal and lingual surfaces. The virtual tooth was the same as the extracted tooth (scanned with a cone beam CT, coloured and edited in ColorMapEditor(®) ), and the plastic tooth presented the best possible match to the extracted tooth. The participants were asked to rate the appearance of the virtual teeth (overall and in terms of caries, restoration and colours), whether the virtual or plastic teeth resembled the extracted teeth better and from which teeth they expected to learn the most (extracted, virtual or plastic). Each group of participants found that the virtual teeth resembled the extracted teeth more than they resembled the plastic teeth; 71% of the participants expected to learn more from the virtual teeth than from the plastic teeth. The results show that the appearance of the virtual teeth was considered more realistic than the appearance of the plastic teeth. The expectation was that the learning opportunities of the virtual teeth are better than of the plastic teeth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Orthodontic-surgical treatment of bilateral maxillary canine impaction

OpenAIRE

Sumitra

2012-01-01

A 13-year-old female patient reported with the chief complaint of irregular front teeth. She had a skeletal Class III and Angle's Class I malocclusion with hyperdivergent growth pattern and bilateral impaction of maxillary canines. Surgical exposure of the impacted teeth and orthodontic alignment was planned. The surgical exposure was done by a minimally invasive modified window technique. Orthodontic treatment of impacted canines without causing significant morbidity to the adjacent teeth an...

Frequency and distribution of developmental anomalies in the permanent teeth of a Turkish orthodontic patient population

Directory of Open Access Journals (Sweden)

Fatih Kazanci

2011-06-01

Conclusion: The prevalence of developmental dental anomalies was higher in females than males. Impacted teeth were the most common developmental dental anomaly in this Turkish orthodontic population, followed by hypodontia.

Saving Single-rooted Teeth with Combined Endodontic-periodontal Lesions.

Science.gov (United States)

Pico-Blanco, Alexandre; Castelo-Baz, Pablo; Caneiro-Queija, Leticia; Liñares-González, Antonio; Martin-Lancharro, Pablo; Blanco-Carrión, Juan

2016-12-01

Teeth affected by combined endodontic-periodontal lesions are usually considered by all prognosis classifications as hopeless teeth. The development of new biomaterials combined with modern endodontic and periodontal regeneration techniques may improve dental prognosis and maintain the affected teeth. Moreover, 1 of the replacement options for those teeth, dental implants, has shown an increasing number of biological and technical complications. Five patients were included in this case series study. Full periodontal and radiographic examination revealed generalized chronic periodontitis. Moreover, endodontic-periodontal lesions affecting single-rooted teeth were detected in those patients with tissue destruction beyond the apex. After splinting those teeth, conventional endodontic and nonsurgical periodontal treatment was performed. Three months later, periodontal regeneration was applied at those teeth in order to reconstruct supporting tissues and to improve dental prognosis. After a follow-up period ranging from 14 months to 17 years, it was observed that all teeth remain asymptomatic and in normal function. No signs of apical pathosis were observed, and the periodontium was stable. All patients were included in a strict maintenance program to check the periodontal and apical status. This case series shows that it is possible to change the prognosis of teeth affected by combined endodontic-periodontal lesions, even if the periodontal support is destroyed beyond the apex. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Natal teeth in an infant with congenital hypothyroidism

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C Venkatesh

2011-01-01

Full Text Available Teeth erupting at birth are referred to as natal teeth. It is a common and benign finding in the neonatal period. However, they may be associated with genetic syndromes like Ellis Van Creveld syndrome and Hallermann-Streiff syndrome. We report here a case of natal teeth in an infant with congenital hypothyroidism.

Comparison of the color of natural teeth measured by a colorimeter and Shade Vision System.

Science.gov (United States)

Cho, Byeong-Hoon; Lim, Yong-Kyu; Lee, Yong-Keun

2007-10-01

The objectives were to measure the difference in the color and color parameters of natural teeth measured by a tristimulus colorimeter (CM, used as a reference) and Shade Vision System (SV), and to determine the influence of color parameters on the color difference between the values measured by two instruments. Color of 12 maxillary and mandibular anterior teeth was measured by CM and SV for 47 volunteers (number of teeth=564). Color parameters such as CIE L*, a* and b* values, chroma and hue angle measured by two instruments were compared. Chroma was calculated as C*ab=(a*2 = b*2)1/2, and hue angle was calculated as h degrees =arctan(b*/a*). The influence of color parameters measured by CM on the color difference (DeltaE*(ab)) between the values measured by two instruments was analyzed with multiple regression analysis (alpha=0.01). Mean DeltaE*(ab) value between the values measured by two instruments was 21.7 (+/-3.7), and the mean difference in lightness (CIE L*) and chroma was 16.2 (+/-3.9) and 13.2 (+/-3.0), respectively. Difference in hue angle was high as 132.7 (+/-53.3) degrees . Except for the hue angle, all the color parameters showed significant correlations and the coefficient of determination (r(2)) was in the range of 0.089-0.478. Based on multiple regression analysis, the standardized partial correlation coefficient (beta) of the included predictors for the color difference was -0.710 for CIE L* and -0.300 for C*(ab) (p<0.01). All the color parameters showed significant but weak correlations except for hue angle. When lightness and chroma of teeth were high, color difference between the values measured by two instruments was small. Clinical accuracy of two instruments should be investigated further.

Estimating Gear Teeth Stiffness

DEFF Research Database (Denmark)

Pedersen, Niels Leergaard

2013-01-01

The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...... and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffness’s of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact length is constant....

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

Energy Technology Data Exchange (ETDEWEB)

Haskell, E.; Kenner, G.; Hayes, R. [Univ. of Utah, Salt Lake City, UT (United States). Center for Applied Dosimetry; Chumak, V.; Shalom, S. [Scientific Center for Radiation Medicine, Kiev (Ukraine)

1997-03-01

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident.

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

International Nuclear Information System (INIS)

Haskell, E.; Kenner, G.; Hayes, R.

1997-01-01

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident

Malocclusion (Misaligned Teeth)

Science.gov (United States)

... and Dental Disorders Malocclusion Causes Treatment More Information Medical Dictionary Also of Interest (Quiz) Biology of the Mouth Additional Content Medical News Malocclusion ˌmal-ə-ˈklü-zhən (Misaligned Teeth) ...

The association between parents' perceived social norms for toothbrushing and the frequency with which they report brushing their child's teeth.

Science.gov (United States)

Trubey, R J; Moore, S C; Chestnutt, I G

2015-06-01

To determine whether parents' judgements on how often other parents brush their children's teeth are associated with the frequency with which they brush their own children's teeth, and their satisfaction with their child's brushing routine. A cross-sectional questionnaire survey completed by 297 parents of children aged 3-6. Parents were asked how often they brushed their own child's teeth per week, how often they thought other parents did so, and how satisfied they were with their child's toothbrushing routine. Demographic data were also collected. The mean frequency that parents brushed their children's teeth was 12.5 times per week. Multiple regression analysis tested the relationship between parents' perceptions of other parents brushing frequency (mean 10.5 times per week) and how often they brushed their own child's teeth, controlling for socio-demographic factors, and yielded a positive association (p parents' satisfaction with their child's brushing routine and the extent to which they thought it was better than that of the average child (p Parents' judgements on how frequently other parents brush their children's teeth are associated with their own behaviour and satisfaction. Re-framing oral health messages to include some form of social normative information ("most parents do this") may prove more persuasive than simple prescriptive advice ("you should do this").

Numerical simulation of the influence of the orifice aperture on the flow around a teeth-shaped obstacle

International Nuclear Information System (INIS)

Cisonni, J; Nozaki, K; Wada, S; Van Hirtum, A; Grandchamp, X

2013-01-01

The sound generated during the production of the sibilant [s] results from the impact of a turbulent jet on the incisors. Several geometric characteristics of the oral tract can affect the properties of the flow-induced noise so that the characterization of the influence of different geometric parameters on the acoustic sources properties allows determining control factors of the noise production. In this study, a simplified vocal tract/teeth geometric model is used to numerically investigate the flow around a teeth-shaped obstacle placed in a channel and to analyze the influence of the aperture at the teeth on the spectral properties of the fluctuating pressure force exerted on the surface of the obstacle, which is at the origin of the dipole sound source. The results obtained for Re = 4000 suggest that the aperture of the constriction formed by the teeth modifies the characteristics of the turbulent jet downstream of the teeth. Thus, the variations of the flow due to the modification of the constriction aperture lead to variations of the spectral properties of the sound source even if the levels predicted are lower than during the production of real sibilant fricative. (paper)

Coevolutionary patterning of teeth and taste buds

Science.gov (United States)

Bloomquist, Ryan F.; Parnell, Nicholas F.; Phillips, Kristine A.; Fowler, Teresa E.; Yu, Tian Y.; Sharpe, Paul T.; Streelman, J. Todd

2015-01-01

Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium. PMID:26483492

Coevolutionary patterning of teeth and taste buds.

Science.gov (United States)

Bloomquist, Ryan F; Parnell, Nicholas F; Phillips, Kristine A; Fowler, Teresa E; Yu, Tian Y; Sharpe, Paul T; Streelman, J Todd

2015-11-03

Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium.

PIXE studies on teeth

International Nuclear Information System (INIS)

Chaudhri, M.A.; Ainsworth, T.

1980-01-01

The elemental composition of healthy and diseased teeth from 25 children has been determined using thick-target proton induced x-ray emission, (PIXE), analysis. Various dental hard tissues: enamel, dentine and cementum, and their junctions, as well as different parts of the same tissue, have been examined individually. A number of elements: Na, Mg, Al, P, S, Cl, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Pb, has been determined in these dental tissues. The concentrations of some of the elements tend to vary considerably from tooth to tooth and tissue to tissue. Attempts have been made to correlate the concentrations of various elements in teeth with their health

Insights into the processes behind the contamination of degraded human teeth and bone samples with exogenous sources of DNA

DEFF Research Database (Denmark)

Gilbert, M. T. P.; Hansen, Anders J.; Willerslev, E.

2006-01-01

A principal problem facing human DNA studies that use old and degraded remains is contamination from other sources of human DNA. In this study we have attempted to contaminate deliberately bones and teeth sampled from a medieval collection excavated in Trondheim, Norway, in order to investigate......, prior to assaying for the residual presence of the handler's DNA. Surprisingly, although our results suggest that a large proportion of the teeth were contaminated with multiple sources of human DNA prior to our investigation, we were unable to contaminate the samples with further human DNA. One...

Integrated Surgical and Orthodontic Treatment: A Twinned Teeth Dilemma

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Seema D Bargale

2015-01-01

Full Text Available Background: Twinned or geminated teeth may cause spacing, caries, aesthetic and periodontal problems which are usually seen in the anterior region. Various treatment methods can be used for correction of double teeth according to the demands of the condition. This article reports bilateral fused maxillary incisor teeth. The fused right side incisor was separated by hemisection and remaining mesial incisal margin was built using composite. Further, comprehensive orthodontic treatment was done to align the anterior maxillary teeth.

Prevalence of early loss of primary teeth in 5-10-year-old school children in Chidambaram town

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S. Syed Shaheed Ahamed

2012-01-01

Full Text Available Introduction : The premature loss of primary teeth may reduce arch length required for the succeeding tooth and, hence, predisposes crowding, rotation and impaction of the permanent teeth. There are only limited studies carried out about the prevalence of early loss of primary teeth. Aim : The present study was performed to evaluate the prevalence of early loss of primary teeth in school children in Chidambaram town in Tamilnadu, India. Settings and Design : A total of 1121 school children (561 boys and 560 girls between 5 and 10 years of age were selected for the study. Materials and Methods : An experienced examiner performed all clinical examinations under natural light. Data including age and missing tooth was collected. Statistical Analysis Used : Microsoft Excel/2000 (Microsoft Office XP data spreadsheet was used and later exported to the Statistical Package for Social Science (SPSS for Windows (version 10.0. Descriptive statistics was applied and, from the results, chi-square tests were applied at a level of significance of 5% (P 0.05. The greatest prevalence was found among the 8-year olds (5.08%, and the most commonly missing teeth were the right lower primary first molars (16.82%. It can be concluded that the prevalence of early loss was high and that the lower primary molars were the most commonly missing teeth in the present study

[Risk factors for teeth aplasia and hypoplasia in cleft lip and palate children].

Science.gov (United States)

Korolenkova, M V; Starikova, N V; Ageeva, L V

2016-01-01

The aim of the study was to assess the significance of environmental risk factors for teeth aplasia and hypoplasia in cleft lip and palate children. Two hundred and forty-seven cleft lip and palate (CLP) children were enrolled in the study including 105 (42.5%) with bilateral CLP and 57.5% with unilateral CLP. The mean age was 11.2±4.9 years. Teeth condition was assessed clinically and radiologically. The impact of risk factors for teeth anomalies was analyzed by retrospective data obtained from computer database (absence of preoperative orthopedic treatment, palatal defects after primary palatoplasty and type of primary procedures). Surgical trauma by early periosteoplasty (at the age of 3-4 months), excessive scarring and tissue traction due to absence of early orthopedic treatment and palatal defect were associated with significantly higher incidence of incisors hypoplasia (both developmental enamel defects and microdentia) and aplasia of central incisors not seen in the other study subgroups. Incisors aplasia and hypoplasia in CLP patients do not always have disembryogenic origin but may depend on external environmental factors, including surgical trauma.

Dental Anomalies in Permanent Teeth after Trauma in Primary Dentition.

Science.gov (United States)

Bardellini, Elena; Amadori, Francesca; Pasini, Stefania; Majorana, Alessandra

This retrospective study aims to evaluate the prevalence of dental anomalies in permanent teeth as a result of a trauma concerning the predecessor primary teeth. A total of 241 records of children (118 males and 123 females, mean age 3.62 ± 1.40) affected by trauma on primary teeth were analyzed. All patients were recalled to evaluate the status of the permanent successor teeth by clinical and radiographic investigations. Out of 241 patients, 106 patients (for a total of 179 traumatized primary teeth) presented at the recall. Dental anomalies on successor permanent teeth were detected in 21 patients (19.8%), for a total of 26 teeth (14.5%) and 28 anomalies. Anomalies of the eruptive process were the most observed disturbances (60.7%), followed by enamel hypoplasia (25%) and white spots (14.3%). A higher percentage of anomalies on permanent teeth was observed when trauma occurred at an age less than 36 months (38.5% of cases). Intrusive and extrusive luxation were related with the most cases of clinical disturbances in the successor permanent teeth. The results of this study highlight the risk of dental anomalies after a trauma in primary dentition, especially in early-aged children and in case of intrusive luxation.

Prevalence of prematurely lost primary teeth in 5-10-year-old children in Thamar city, Yemen: A cross-sectional study.

Science.gov (United States)

Murshid, Sakhr A; Al-Labani, Mohammed A; Aldhorae, Khalid A; Rodis, Omar M M

2016-08-01

The premature loss of primary teeth is a potential risk factor for poor arch length development. Adequate arch length is important to the progression of the permanent teeth. Poor arch length can lead to crowding, ectopic eruption, or impaction of these teeth. This study is designed to assess the prevalence of premature loss of primary teeth in the 5-10-year-old age group. The study group included 185 children, that is, 91 boys and 94 girls. The dental examination was conducted by an experienced examiner under sufficient artificial light. Data including patient age and missing teeth were collected. Descriptive statistics were applied for data analysis, and from the results, Chi-square tests were used at a level of significance of 5% (P premature loss of primary teeth with no statistically significant difference between genders. The lower left primary second molar was the most commonly absent tooth in the dental arch (13.5%). The status of premature loss of primary teeth was high in the study group. Implementation of efficient educational and preventive programs to promote oral health would help children maintain a healthy primary dentition and eventually prevent the disturbances in the future development of normal occlusion. Early detection and management of the space problems associated with the early loss of primary teeth would help in reducing malocclusion problems.

Evaluation of crown mesiodistal diameter of permanent teeth

Directory of Open Access Journals (Sweden)

H. Ravanmehr

1994-06-01

Full Text Available The aim of this study was to evaluate mesiodistal diameter of permanent teeth and evaluating it's distribution in Iran. In current study, 850 plastery impressions or 16590 teeth were precisely measured by a digital coulis with 0.01 mm accuracy.The obtained measures of the permanent teeth are shown in table 1. Table (4 demonstrates the symmetry of left and right maxillary and mandibular teeth. Obtainedmeasurements in Table 1 were compared with Gran's measures (Table 2 which are shown in Table (3.Bolton analysis was done and results were found close to the BolType text or a website address or translate a document.ton measures. It was concluded that it is better to replace measurements of our society instead of Bolton's. Since we found minor difference with the measures of other researchers, especially for teeth anterior to first molar, using our measures in treatment plans would not bring about any problem.

The length of teeth : A statistical analysis of the differences in length of human teeth for radiologic purposes

NARCIS (Netherlands)

Verhoeven, J.W.; Aken, J. van; Weerdt, G.P. van der

Intraoral radiograms can be made according to the long tube paralleling technique utilizing aiming devices. An important factor in the design of these instruments is the length of the teeth to be radiographed. Reliable data regarding the length of the teeth in the different regions of the mouth are

Bond strength test of acrylic artificial teeth with prosthetic base

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Erna Kurnikasari

2008-07-01

Full Text Available Denture consists of acrylic artificial teeth and acrylic prothesis base bond chemically with a bond strength of 315 kgF/cm2. Most of the commercial acrylic artificial teeth do not specify their specifications and all of those acrylic artificial teeth do not include mechanical data (bond strength. The aim of this study is to discover which acrylic artificial teeth meet ADA specification no. 15. This study is a descriptive analytic study performed to 5 acrylic artificial teeth posterior brands commonly used by dentists and technicians. From each brand, 3 sample teeth were taken. The acrylic artificial teeth were prepared into a rectangular shape and were attached between acrylic prothesis base simulation and jigs. The sample was given tensile load using a Universal Testing Machine. The amount of force that causes the teeth to be fractured was recorded and the bond strength was calculated. The results of the study show that the average value for the five acrylic artificial teeth for the five brands were as followed: Brand A, 125.993 kgF/cm2; B, 188.457 kgF/cm2; C, 175.880 kgF/cm2; D, 153.373 kgF/cm2; E, 82.839 kgF/cm2. The data can be tested statistically by using One Way ANOVA test and Dunnett test (alpha = 0.05. From the study, it is concluded that the five acrylic artificial teeth have a bond strength below the ADA specification no. 15.

Cleidocranial Dysplasia Case Report: Remodeling of Teeth as Aesthetic Restorative Treatment

Directory of Open Access Journals (Sweden)

Leonardo Fernandes da Cunha

2014-01-01

Full Text Available Cleidocranial dysplasia (CCD, is an autosomal dominant disorder with a prevalence of 1 in 1,000,000 individuals. It is generally characterized by orofacial manifestations, including enamel hypoplasia, retained primary teeth, and impacted permanent and supernumerary teeth. The successful treatment involving a timing intervention (orthodontic-maxillofacial surgeons-restorative is already described. However, the restorative treatment might improve the aesthetic final result in dentistry management for patients with cleidocranial dysplasia. Objective. Therefore, this clinical report presents a conservative restorative management (enamel microabrasion, dental bleaching, and direct composite resin for aesthetic solution for a patient with CCD. Clinical Considerations. The cosmetic remodeling is a conservative, secure, and low cost therapy that can be associated with other procedures such as enamel microabrasion and dental bleaching to achieve optimal outcome. Additionally, the Golden Proportion can be used to guide dental remodeling to improve the harmony of the smile and the facial composition. Conclusions. Thus, dentists must know and be able to treat dental aesthetic problems in cleidocranial dysplasia patients. The intention of this paper is to describe a restorative approach with the cosmetic remodeling teeth (by grinding or addicting material associated with enamel microabrasion and dental bleaching to reestablish the form, shape, and color of smile for patients with cleidocranial dysplasia.

Immunohistochemical studies of the periodontal membrane in primary teeth

DEFF Research Database (Denmark)

Bille, Marie-Louise Bastholm; Nolting, Dorrit; Kjær, Inger

2009-01-01

Objectives. To describe the periodontal membrane of human primary teeth immunohistochemically, while focusing on the epithelial layer of Malassez, fibers, and peripheral nerves, and to compare the findings with those of a previous study of human permanent teeth. Material and methods. Nineteen human...... could be identical to those in regions with no resorption. Conclusion. In regions without resorption, spatial organization of the periodontal membrane of primary teeth was similar to that of permanent teeth, although the number and distribution of epithelial cells and fibers differed. In regions...

Impact strength of small icy bodies that experienced multiple collisions

Science.gov (United States)

Yasui, Minami; Hayama, Ryo; Arakawa, Masahiko

2014-05-01

Frequent collisions are common for small bodies in the Solar System, and the cumulative damage to these bodies is thought to significantly affect their evolution. It is important to study the effects of multiple impacts such as the number of impacts on the impact strength and the ejection velocity of impact fragments. Here we conducted multiple-impact experiments using a polycrystalline water ice target, varying the number of impacts from 1 to 10 times. An ice cylindrical projectile was impacted at 84-502 m s-1 by using a single-stage gas gun in a cold room between -10 and -15 °C. The impact strength of the ice target that experienced a single impact and multiple impacts is expressed by the total energy density applied to the same target, ΣQ, and this value was observed to be 77.6 J kg-1. The number of fine impact fragments at a fragment mass normalized by an initial target mass, m/Mt0 ∼ 10-6, nm, had a good correlation with the single energy density at each shot, Qj, and the relationship was shown to be nm=10·Qj1.31±0.12. We also estimated the cumulative damage of icy bodies as a total energy density accumulated by past impacts, according to the crater scaling laws proposed by Housen et al. (Housen, K.R., Schmidt, R.M., Holsapple, K.A. [1983]. J. Geophys. Res. 88, 2485-2499) of ice and the crater size distributions observed on Phoebe, a saturnian icy satellite. We found that the cumulative damage of Phoebe depended significantly on the impact speed of the impactor that formed the craters on Phoebe; and the cumulative damage was about one-third of the impact strength ΣQ* at 500 m s-1 whereas it was almost zero at 3.2 km s-1.

Evaluation of bond strength of self-etching adhesives having different pH on primary and permanent teeth dentin.

Science.gov (United States)

Ozmen, Bilal; Koyuturk, Alp Erdin; Tokay, Ugur; Cortcu, Murat; Sari, Mustafa Erhan

2015-10-16

The purpose of this in vitro study was to evaluate the dentin shear bond strength of 4 self-etching adhesives having a different pH on primary and permanent teeth dentin. The occlusal enamel was removed from 60 freshly extracted third molar and 60 primary second molar human teeth, which were randomly separated into 4 groups (n = 15). Four adhesive systems were applied: G-Bond (GC Corporation, Tokyo, Japan, pH: 1.5), Futura Bond M (Voco, Cuxhaver, Germany, pH: 1.4), Adper Prompt L-Pop (3M/ESPE, St Paul, MN, USA, pH: 0.8), and Clearfil S(3) Bond (Kuraray Medical, Tokyo, Japan, pH: 2.7) according to the manufacturer's instructions. After the application of dentin bonding agents, a composite resin material (Z250 Restorative A2, 3M ESPE, St. Paul, MN, USA) for permanent teeth and a compomer resin material (Dyract Extra A2, Dentsply, Konstanz, Germany) for primary teeth was applied onto the prepared dentin surfaces. The data were obtained by using a universal test machine at a crosshead speed of 1 mm/min. The mean values were compared using Tukey's multiple comparison test. Although there was no difference between adhesives on the permanent teeth, Clearfil S3 adhesive showed higher bond (18.07 ± 0.58 MPa) (P>0.05). Lower bond strength values were obtained from primary teeth and especially G-Bond adhesive (9.36 ± 0.48 MPa) (Padhesives with different pH and solvent types can be used successfully for permanent teeth dentin but adhesives with low pH did not provide greater shear bond strength values.

Teeth: Among Nature's Most Durable Biocomposites

Science.gov (United States)

Lawn, Brian R.; Lee, James J.-W.; Chai, Herzl

2010-08-01

This paper addresses the durability of natural teeth from a materials perspective. Teeth are depicted as smart biocomposites, highly resistant to cumulative deformation and fracture. Favorable morphological features of teeth at both macroscopic and microscopic levels contribute to an innate damage tolerance. Damage modes are activated readily within the brittle enamel coat but are contained from spreading catastrophically into the vulnerable tooth interior in sustained occlusal loading. Although tooth enamel contains a multitude of microstructural defects that can act as sources of fracture, substantial overloads are required to drive any developing cracks to ultimate failure—nature's strategy is to contain damage rather than avoid it. Tests on model glass-shell systems simulating the basic elements of the tooth enamel/dentin layer structure help to identify important damage modes. Fracture and deformation mechanics provide a basis for analyzing critical conditions for each mode, in terms of characteristic tooth dimensions and materials properties. Comparative tests on extracted human and animal teeth confirm the validity of the model test approach and point to new research directions. Implications in biomechanics, especially as they relate to dentistry and anthropology, are outlined.

EPR dosimetry of teeth in past and future accidents. A prospective look at a retrospective method

Energy Technology Data Exchange (ETDEWEB)

Haskell, E.; Kenner, G.; Hayes, R. [Center for Applied Dosimetry, Salt Lake City, UT (United States); Chumak, V.; Shalom, S.

1996-12-31

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Chelyabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose; and teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident. (author)

Orthodontics Align Crooked Teeth and Boost Self-Esteem

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... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem print full article print this chapter email this ...

21 CFR 872.6475 - Heat source for bleaching teeth.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Heat source for bleaching teeth. 872.6475 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6475 Heat source for bleaching teeth. (a) Identification. A heat source for bleaching teeth is an AC-powered device that consists of a...

A 5-year follow-up case of multiple intrusive luxative injuries

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Seema Thakur

2012-01-01

Full Text Available Introduction: Traumatic intrusive luxation is one of the most severe forms of dental injuries, usually affecting the maxillary incisors. The consequence of such an occurrence is a high risk of healing complications such as pulp necrosis, external inflammatory resorption, and external replacement resorption (ankylosis. Case Report: This report presents a case of severe intrusive luxation of multiple anterior teeth in an 11-year-old girl. The teeth were repositioned successfully by endodontic and orthodontic management. The case was monitored for 5 years. Discussion: Depending on the severity of the injury, different clinical approaches for treatment of intrusive luxation may be used. Despite the variety of treatment modalities, rehabilitation of intruded teeth is always a challenge and a multidisciplinary approach is important to achieve a successful result. In this case, intruded teeth were endodontically treated with multiple calcium hydroxide dressings and repositioned orthodontically. The follow-up of such cases is very important as the repair process after intrusion is complex. After 5 years, no clinical or radiographic pathology was detected.

Trigeminocardiac reflex during non-surgical root canal treatment of teeth with irreversible pulpitis

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James I.-Sheng Huang

2018-06-01

Full Text Available Background/Purpose: Trigeminocardiac reflex (TCR is a unique clinical incident of acute change in hemodynamic balance, which may lead to hypotension, bradycardia, and even clinical crisis. Up to date, no study so far considers the impact of non-surgical root canal treatment (NSRCT of irreversible pulpitis teeth under either local infiltration or block anesthesia on hemodynamic change possibly related to TCR. Methods: This study enrolled 111 patients with 138 irreversible pulpitis teeth that were treated by two sessions of NSRCT. The first session involved mainly the removal of vital pulp tissue with the direct stimulation of the dental branches of the trigeminal nerve, and the second session included the root canal enlargement and debridement with minimal disturbance to the dental branches of the trigeminal nerve. Vital signs mainly the blood pressure were recorded during both NSRCT sessions. Results: The incidences of NSRCT patients with MABP decrease ≧10%, ≧15%, or ≧20% were all significantly higher in the first NSRCT session than in the second NSRCT session (all the P-values < 0.001. In the first NSRCT session, the incidence of patients with MABP decrease ≧10% was significantly associated with tooth type. For both upper and lower teeth, the patients with premolars treated by NSRCR had significantly higher incidences of MABP decrease ≧10% than those with either anterior or molar teeth treated by NSRCR (all the P-values < 0.05. Conclusion: We conclude that vital pulp extirpation may lead to a substantial drop in patient's blood pressure possibly related to TCR. Keywords: Trigeminocardiac reflex, Non-surgical root canal treatment, Irreversible pulpitis, Mean arterial blood pressure, Hypotension, Teeth

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

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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.

Study of external root resorption during orthodontic treatment in root filled teeth compared with their contralateral teeth with vital pulps.

Science.gov (United States)

Llamas-Carreras, J M; Amarilla, A; Solano, E; Velasco-Ortega, E; Rodríguez-Varo, L; Segura-Egea, J J

2010-08-01

To determine whether root filled teeth and those with vital pulps exhibit a similar degree of external root resorption (ERR) as a consequence of orthodontic treatment. The study sample consisted of 77 patients, with a mean age of 32.7 +/- 10.7 years, who had one root filled tooth before completion of multiband/bracket orthodontic therapy for at least 1 year. For each patient, digital panoramic radiographs taken before and after orthodontic treatment were used to determine the proportion of external root resorption (PRR), defined as the ratio between the root resorption in the root filled tooth and that in its contralateral tooth with a vital pulp. The student's t-test, anova and logistic regression analysis were used to determine statistical significance. The mean PRR was 1.00 +/- 0.13, indicating that, in the total sample, there were no significant differences in root resorption in the root filled teeth and their contralateral teeth with vital pulps. Multivariate logistic regression analysis suggested that PRR was significantly greater in incisors (P = 0.0014; odds ratio = 6.2885, C.I. 95% = 2.0-19.4), compared to other teeth, and in women (P = 0.0255; odds ratio = 4.2, C.I. 95% = 1.2-14.6), compared to men. There was no significant difference in the amount or severity of external root resorption during orthodontic movement between root filled teeth and their contralateral teeth with vital pulps.

Prevalence of prematurely lost primary teeth in 5–10-year-old children in Thamar city, Yemen: A cross-sectional study

Science.gov (United States)

Murshid, Sakhr A.; Al-Labani, Mohammed A.; Aldhorae, Khalid A.; Rodis, Omar M. M.

2016-01-01

Objectives: The premature loss of primary teeth is a potential risk factor for poor arch length development. Adequate arch length is important to the progression of the permanent teeth. Poor arch length can lead to crowding, ectopic eruption, or impaction of these teeth. This study is designed to assess the prevalence of premature loss of primary teeth in the 5-10-year-old age group. Materials and Methods: The study group included 185 children, that is, 91 boys and 94 girls. The dental examination was conducted by an experienced examiner under sufficient artificial light. Data including patient age and missing teeth were collected. Descriptive statistics were applied for data analysis, and from the results, Chi-square tests were used at a level of significance of 5% (P premature loss of primary teeth with no statistically significant difference between genders. The lower left primary second molar was the most commonly absent tooth in the dental arch (13.5%). Conclusion: The status of premature loss of primary teeth was high in the study group. Implementation of efficient educational and preventive programs to promote oral health would help children maintain a healthy primary dentition and eventually prevent the disturbances in the future development of normal occlusion. Early detection and management of the space problems associated with the early loss of primary teeth would help in reducing malocclusion problems. PMID:27652244

Direct composite restoration of permanent anterior teeth uncomplicated crown fractures

Directory of Open Access Journals (Sweden)

Ashley Evans Nicholas

2018-01-01

Full Text Available An uncomplicated crown fracture is a fracture that involves only the tooth enamel or the dentin and tooth enamel without any damage or exposure to the pulp. Crown fracture of the anterior teeth usually caused by traumatic forces such as falls, accidents, violence, or sports activities. Traumatic injuries of the oral region frequently involve the anterior teeth, especially maxillary incisors due to the anatomic factors which may affect the functional and aesthetical values of the teeth. The objective of this literature study was to know more about uncomplicated crown fracture of the anterior teeth and its restoration. This research was a literature study performed by researching, highlighting various interesting facts and compiling the relevant published journals. The most common and ideal direct restoration of the anterior teeth was the composite resin restoration. The anterior teeth restoration was considered to be a complex and challenging case to solves due to the fact that besides reconstructing the tooth and regaining the function, the aesthetical aspect was also becoming the main objectives. The permanent anterior teeth uncomplicated crown fracture was the most common case of tooth fractures which was mainly caused by traumatic injuries such as falls, accidents, excessive forces, violence, and also sports activities. Dental injuries of the anterior teeth also affected the aesthetical properties and the function of the tooth. Composite resin restoration was able to performed directly on the permanent anterior teeth uncomplicated crown fracture.

Improvement in properties of plastic teeth by electron beam irradiation

International Nuclear Information System (INIS)

Sano, Yuko; Ishikawa, Shun-ichi; Seguchi, Tadao

2011-01-01

Improvement of the comfort and esthetics of artificial plastic teeth is desirable for the recently increasing numbers of elderly in society. Plastic teeth made of polycarbonate (PC) were modified by electron beam (EB) irradiation under specific conditions, and the change in the chemical properties of the PC was investigated. The water absorption, glucose attachment, level of bis-phenol-A (BPA) extraction, maltose adhesion, and mucin adhesion on the PC teeth were measured before and after EB irradiation. EB irradiation to a dose of 3.5 kGy at 150 o C in a nitrogen gas atmosphere reduced the water absorption by 20%, glucose absorption by 40%, maltose adhesion by 20%, and the amount of various amino acids, formed as the hydrolysis products of mucin, adhering on the PC teeth were reduced by 60-99%. The BPA content was lower than the detection limit for analysis of both the original and the EB irradiated PC teeth. - Highlights: → Radiation improvement of polycarbonate for plastic teeth by EB irradiation 3.5 kGy at 150 o C in inert gas. → Water and glucose absorption and maltose adhesion on PC teeth were much reduced. → Bis-phenol-A content from PC teeth was lower than the detection limit after irradiation.

Oral health- related quality of life in patients with rare inherited diseases affecting bone and teeth

DEFF Research Database (Denmark)

Gjørup, Hans; Haubek, Dorte

Background X-linked hypophosphatemia (XLH) is a rare hereditary disease characterized by insufficient bone mineralization. Osteogenesis imperfecta (OI) is another rare inherited disease characterized by fragile bones because of defective collagen synthesis. Both diseases may have impact on teeth...

Orthodontic management of impacted central incisor: A clinical challenge

Directory of Open Access Journals (Sweden)

Amit Kumar Khera

2017-01-01

Full Text Available Multiple treatment options are available for patients who have impacted incisor. This paper shows a case in which orthodontic as well as surgical considerations in 10-year-old female child were presented in the management of impacted central incisor. The orthodontic treatment plan included three steps – creation of space, exposure of crown, and forced eruption. A unique and innovative technique for orthodontic traction (0.017 × 0.025 TMA wire with palatal extension was employed to move the maxillary incisor into arch, with minimum injury to neighboring soft tissue. After the successful management of impacted teeth, it is very important to periodically review the periodontal condition and stability.

Demineralization-remineralization dynamics in teeth and bone.

Science.gov (United States)

Abou Neel, Ensanya Ali; Aljabo, Anas; Strange, Adam; Ibrahim, Salwa; Coathup, Melanie; Young, Anne M; Bozec, Laurent; Mudera, Vivek

Biomineralization is a dynamic, complex, lifelong process by which living organisms control precipitations of inorganic nanocrystals within organic matrices to form unique hybrid biological tissues, for example, enamel, dentin, cementum, and bone. Understanding the process of mineral deposition is important for the development of treatments for mineralization-related diseases and also for the innovation and development of scaffolds. This review provides a thorough overview of the up-to-date information on the theories describing the possible mechanisms and the factors implicated as agonists and antagonists of mineralization. Then, the role of calcium and phosphate ions in the maintenance of teeth and bone health is described. Throughout the life, teeth and bone are at risk of demineralization, with particular emphasis on teeth, due to their anatomical arrangement and location. Teeth are exposed to food, drink, and the microbiota of the mouth; therefore, they have developed a high resistance to localized demineralization that is unmatched by bone. The mechanisms by which demineralization-remineralization process occurs in both teeth and bone and the new therapies/technologies that reverse demineralization or boost remineralization are also scrupulously discussed. Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties of the tooth and bone in addition to promoting more natural repair of surrounding tissues. Turning these new technologies to products and practices would improve health care worldwide.

Survivability of systems under multiple factor impact

International Nuclear Information System (INIS)

Korczak, Edward; Levitin, Gregory

2007-01-01

The paper considers vulnerable multi-state series-parallel systems operating under influence of external impacts. Both the external impacts and internal failures affect system survivability, which is determined as the probability of meeting a given demand. The external impacts are characterized by several destructive factors affecting the system or its parts simultaneously. In order to increase the system's survivability a multilevel protection against the destructive factors can be applied to its subsystems. In such systems, the protected subsystems can be destroyed only if all of the levels of their protection are destroyed. The paper presents an algorithm for evaluating the survivability of series-parallel systems with arbitrary configuration of multilevel protection against multiple destructive factor impacts. The algorithm is based on a composition of Boolean and the Universal Generating Function techniques. Illustrative examples are presented

Teeth characterization using ion beam analysis

International Nuclear Information System (INIS)

Rizzutto, M.A.; Added, N.; Tabacniks, M.H.; Falla-Sotelo, F.; Curado, J.F.; Francci, C.; Markarian, R.A.; Quinelato, A.; Youssef, F.; Mori, M.; Youssef, M.

2006-01-01

A collaboration project between the School of Dentistry and the Institute of Physics of the University of Sao Paulo has been established to measure elemental concentrations in teeth by proton induced X-ray emission (PIXE) and heavy ion elastic recoil detection analysis (HI-ERDA) techniques. Data on trace elements in human, bovine and swine teeth, analyzed by PIXE with a 2.4 MeV proton beam, were compared and concentrations for several elements were obtained with tens of μg/g sensitivity. HI-ERDA measurements employing a 52 MeV Cl beam were done to evaluate changes in elementary concentration in dental enamel after bleaching treatment with different products in 25 bovine incisors teeth. This nondestructive technique allowed the measurements of Ca, P, O and C concentrations above the limit of 100 μg/g. (author)

Alignment of displaced or impacted teeth with the traction chain.

Science.gov (United States)

Sander, Franz Martin; Sander, Christian; Sander, Franz Günter

2006-07-01

To align those teeth in the dental arch that cannot erupt or are displaced, they must be surgically exposed. After the traction device is attached, the tooth is again covered with the mucoperiosteal flap to protect the tissues involved. For this reason, the loss of this traction device must be absolutely avoided in order to prevent another surgical intervention. Here at the University of Ulm, we have developed and tested an optimized traction chain for that purpose. The chain is attached to the tooth with a laser-roughened pad applying the acid-etching technique. The chain links serve as fixation elements for traction devices such as elastic ligatures or piggyback archwires. At the same time, one can determine the distance covered by the tooth by the number of the erupting chain links. We demonstrate the clinical application of this traction device in two cases.

Injuries of deciduous and permanent teeth in children (diagnostic measures, medical tactics

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Yakovenko L.N.

2016-12-01

Full Text Available A retrospective analysis of 1147 patients’ records from the clinic of the department of surgical dentistry and maxillofacial surgery of childhood of NMU Bogomolets and 944 case histories of patients with traumatic injuries of maxillofacial region in the clinic of the department of pediatric dentistry of SE «Dnepropetrovsk medical academy of Health Ministry of Ukraine» has shown that traumatic damages to teeth make up 18.8% of all injuries in maxillofacial region. It was found that in most cases the cause of injury is fall of a child - 60%, punching on the face - 19%, other causes – 21%. Most often maxillary central incisors are affected - about 70-80%, lateral - 10-20% both in temporary and in shift bite. Lower incisors are injured only in 1-6% of cases. Injuries of the temporary teeth were observed in 30-45% of cases. The aim of the study was to determine the major diagnostic methods and therapeutic measures that have been used in trauma of permanent and temporary teeth in children of different ages. Diagnostic measures included clinical and instrumental studies. Of the additional survey methods of dental trauma in 90% of cases back-side X-ray, in 7-8% – orthopanto­mography, in 1-2% - CT were performed. In dislocations of temporary teeth X-ray examination was carried out only in impacted dislocation. Algorithm of treatment tactics for almost all kinds of temporary teeth dislocations was to remove it, not taking into account the degree of formation of the tooth root and functional ability of the tooth, that involves the development of the indications for their preservation. Most often, for the immobilization of the injured permanent teeth a smooth splin-clamp (85% was used, it is cheap, easy to manufacture, reliable for fixing, individual as for adaptation, but when applied it leads to injury of periodontal tissues, the development of inflammatory processes in them. Alternative methods of fixation were splint systems, splint-caps and

Fracture resistance of teeth submitted to several internal bleaching protocols.

Science.gov (United States)

Leonardo, Renato de Toledo; Kuga, Milton Carlos; Guiotti, Flávia Angélica; Andolfatto, Carolina; Faria-Júnior, Norberto Batista de; Campos, Edson Alves de; Keine, Kátia Cristina; Dantas, Andrea Abi Rached

2014-03-01

The aim of this study was to evaluate the fracture resistance of teeth submitted to several internal bleaching protocols using 35% hydrogen peroxide (35HP), 37% carbamide peroxide (37CP), 15% hydrogen peroxide with titanium dioxide nanoparticles (15HPTiO2) photoactivated by LED-laser or sodium perborate (SP). After endodontic treatment, fifty bovine extracted teeth were divided into five groups (n = 10): G1-unbleached; G2-35HP; G3-37CP; G4-15HPTiO2 photoactivated by LED-laser and G5-SP. In the G2 and G4, the bleaching protocol was applied in 4 sessions, with 7 days intervals between each session. In the G3 and G5, the materials were kept in the pulp teeth for 21 days, but replaced every 7 days. After 21 days, the teeth were subjected to compressive load at a cross head speed of 0.5 mm/min, applied at 135° to the long axis of the root using an eletromechanical testing machine, until teeth fracture. The data were submitted to ANOVA and Tukey tests (α = 5%). The 35HP, 37CP, 15HPTiO2 and SP showed similar fracture resistance teeth reduction (p > 0.05). All bleaching treatments reduced the fracture resistance compared to unbleached teeth (p endodontically-treated teeth, but there were no differences between each other. There are several internal bleaching protocols using hydrogen peroxide in different concentrations and activation methods. This study evaluated its effects on fracture resistance in endodontically-treated teeth.

Impacted Mandibular Third Molars: Review of Literature and a ...

African Journals Online (AJOL)

were screened, and 50 articles were included in the review. Causes of ... impaction rate is higher for third molars when compared with other teeth. The mandibular .... Hence, the surgical extraction of these impacted teeth has become the most ...

Prosthodontic management of a patient with Gardner′s syndrome: A clinical case report

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Kunwarjeet Singh

2014-01-01

Full Text Available Gardner′s syndrome is a genetic condition demonstrating an autosomal dominant trait and characterized by the multiple colonic polyps (familial adenomatous polyposis coli with sebaceous cysts and jaw osteomas. Various dental abnormalities present in patient′s suffering with this syndrome includes multiple impacted or unerupted teeth, supernumerary teeth, hypodontia, compound odontomes and dentigerous cyst. In this case report, a patient with Gardner′s syndrome who suffered from functional and psychological problems owing to multiple impacted, unerupted teeth and hypodontia was presented. Patient was treated with a maxillary conventional overdenture opposing mandibular custom bar supported overdentures.

Teeth Caries Decay in MR Imaging

International Nuclear Information System (INIS)

Tanasiewicz, M.M.; Kupka, T.W.; Weglarz, W.P.; Jasinski, A.

2005-01-01

X-ray based visualization techniques were for many years the only way to asses structure and state of the human teeth. MRI has been used in the research of the healthy and decayed teeth during last decade. Several papers were presented showing usefulness of spin echo and gradient echo imaging, Single Point Imaging, SPRITE and STRAFI techniques for visualization of the dental surface geometry as well as for distinction between soft tissue (pulp) and mineralized tissue (enamel, dentine and root cement) in the extracted teeth. Recently, MRI was used for estimation of the facial bone structure, in preparation to implantation, localization of the tumor in the facial bone tissue, and in detection of the osteoporosis. The aim of this work was to investigate potential of MRI for detection and estimation of the caries, on the level of laboratory pre-clinical tests. This work was done within the project to develop original, MRI based diagnostic technique for dentistry needs. MRI experiments were performed on the 5 decayed extracted human teeth (impossible conservative therapy), obtained at Dept. of Dental Surgery MUS. After extraction teeth were stored in saline. MRI measurements were done in MR Tomography Lab INP. Prior to the experiment, tooth was degassed to minimize magnetic susceptibility artifacts. A 3D spin echo pulse sequence on the 4.7 T research MRI system, equipped with Maran DRX console, and dedicated home-built probe head, was used to obtain three dimensional (256x128x128) images of the teeth. Corresponding resolution was 60x120x160 mm 3 . High intensity signal from water penetrated into the porous decayed regions of tooth, contrasted with lack of signal from mineralized tooth tissue, allow for visualization of the presence and extent of caries. Among the 5 measured teeth, MRI allows for detection of the caries in two most decayed tooth. High intensity signal from water penetrated into the porous decayed regions of tooth, contrasted with lack of signal from

Outcome of Endodontically Treated Cracked Teeth

Science.gov (United States)

2016-06-01

directed by: CAPT Te!Ty Webb, D.D.S., M.S. A " cracked tooth" is defined as a thin surface enamel and dentin disruption of unknown depth, and is often...OUTCOME OF ENDODONTICALL Y TREATED CRACKED TEETH by David Michael Dow II, D.D.S. Lieutenant Commander, Dental Corps United States Navy A thesis...copyrighted material in the thesis manuscript titled: "Outcome ofEndodontically Treated Cracked Teeth" is appropriately acknowledged and, beyond

Multiple electron processes of He and Ne by proton impact

Science.gov (United States)

Terekhin, Pavel Nikolaevich; Montenegro, Pablo; Quinto, Michele; Monti, Juan; Fojon, Omar; Rivarola, Roberto

2016-05-01

A detailed investigation of multiple electron processes (single and multiple ionization, single capture, transfer-ionization) of He and Ne is presented for proton impact at intermediate and high collision energies. Exclusive absolute cross sections for these processes have been obtained by calculation of transition probabilities in the independent electron and independent event models as a function of impact parameter in the framework of the continuum distorted wave-eikonal initial state theory. A binomial analysis is employed to calculate exclusive probabilities. The comparison with available theoretical and experimental results shows that exclusive probabilities are needed for a reliable description of the experimental data. The developed approach can be used for obtaining the input database for modeling multiple electron processes of charged particles passing through the matter.

Clinical research of teeth damage from radiotherapy

International Nuclear Information System (INIS)

Li Erzhou; Yan Maosheng; Chen Wei; Li Qing

2003-01-01

Objective: To analyze various factors inducing teeth damage from radiotherapy and the preventive and treatment methods. Methods: One hundred cases of patients treated by radiotherapy were divided into two groups. In group one there were 60 cases whose teeth were irradiated during treatment; in group two there were 40 cases whose teeth were not irradiated during treatment. Results: The caries incidence was 60% for group one and 15% for group two (P<0.01). By auto-control in 15 patients, the caries incidence on the sick side was obviously higher than that of the healthy side. Hundred percent caries incidence was found in 6 cases who received a dosage of 70 Gy. Conclusion: The authors believe that radiation damage to the teeth is associated with the following factors: 1. The dosage and location of irradiation are closely related to caries incidence; 2. The active dentinoblasts are very sensitive to radiation; 3. Damage to the salivary glands from radiotherapy can result in reduction of salvia and pH value, leading to a high growth rate of Streptococcus mutans. Following preventive measures could be considered in future cases: to apply a caries prevention coating or protective dental crown and TPS, to adjust the dose and time of irradiation, to select conformal radiotherapy technique. The key points for protecting the teeth and salivary gland from caries and damage are protection of the proliferation ability of pulp cells, anti-inflammation, promotion of microcirculation, and strengthening body resistance

Replacement of Missing Anterior Teeth in a Patient with Temporomandibular Disorder

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Satheesh B. Haralur

2014-01-01

Full Text Available The loss of anterior teeth leads to extreme psychological trauma, along with functional and esthetic debilitations. Healthy anterior teeth play an important role of protecting the posterior teeth during excursive mandibular movement. Loss of anterior teeth induces posterior interference with extended disocclusion time. Posterior disocclusion is critical to remove the harmful force on the teeth temporomandibular joint and eliminate muscle hypertonicity. Occlusal interference is considered as contributing factor to temporomandibular disorder (TMD symptoms. Prosthesis design should eliminate deleterious tooth contacts. Establishing optimum anterior guidance is a key to establishing harmonious functional occlusion in addition to the correction of the esthetic and phonetic disabilities. This case report explains the steps involved in the rehabilitation of the TMD patient with loss of maxillary anterior teeth.

Integrated Surgical and Orthodontic Treatment: A Twinned Teeth Dilemma

OpenAIRE

Seema D Bargale; D P Shital Kiran; KVR Anuradha; Smit Sikligar

2015-01-01

Background: Twinned or geminated teeth may cause spacing, caries, aesthetic and periodontal problems which are usually seen in the anterior region. Various treatment methods can be used for correction of double teeth according to the demands of the condition. This article reports bilateral fused maxillary incisor teeth. The fused right side incisor was separated by hemisection and remaining mesial incisal margin was built using composite. Further, comprehensive orthodontic treatment was done ...

Genome-wide association study identifies four loci associated with eruption of permanent teeth

DEFF Research Database (Denmark)

Geller, Frank; Feenstra, Bjarke; Zhang, Hao

2011-01-01

The sequence and timing of permanent tooth eruption is thought to be highly heritable and can have important implications for the risk of malocclusion, crowding, and periodontal disease. We conducted a genome-wide association study of number of permanent teeth erupted between age 6 and 14 years......, analyzed as age-adjusted standard deviation score averaged over multiple time points, based on childhood records for 5,104 women from the Danish National Birth Cohort. Four loci showed association at P...

[Retrospective analysis of pulp revascularization in immature permanent teeth with diffuse pulpitis].

Science.gov (United States)

Peng, C F; Zhao, Y M; Yang, Y; Liu, H; Qin, M

2017-01-09

Objective: To evaluate the treatment effectiveness of revascularization in immature permanent teeth with diffuse pulpitis and to provide an alternative approach for the treatment of these teeth. Methods: Clinical and radiographic data were collected from 17 immature permanent teeth which were diagnosed as diffuse pulpitis and with their pulp extirpated at Emergency Department of Peking University School and Hospital of Stomatology. All these teeth were treated using pulp revascularization at Department of Pediatric Dentistry. Clinical success rate was then evaluated based on the clinical and radiographic findings. The increase of root length and dentin wall thickness of the revascularized teeth and the contralateral control teeth were measured and compared according to the preoperative and recall periapical radiographs. Results: The average follow-uptime is (25.8±9.9) months (12-46 months). Totally 13 out of the 17 teeth showed normal clinical and radiographic manifestation and achieved the increasein root length and dentin wall thickness. They met criteria for success treatment. The rest 4 out of the 17 teeth also showed root length and dentin wall thickness increaseand apical foramen closure. However, periapical inflammations were observed during 12 to 36 monthfollow-ups. These cases were recognized as failed. In all the17 teeth, the increase of root length and dentin wall thickness was not significantly different between the revascularized teeth and the contralateral control teeth ( P> 0.05). Conclusions: Pulp revascularization in young permanent teeth with diffuse pulpitis resulted in similar clinical outcomes in root development and root canal wall formation compared with the contralateral control teeth. However, reinfection might occur during long-term follow-up.

Clinical Analysis of Analgesics and Steroids Use for Extraction of Teeth in Patients with Intellectual Disability Under General Anesthesia.

Science.gov (United States)

Maeda, Shigeru; Honda, Yuka; Tanimura, Hiroshi; Tomoyasu, Yumiko; Higuchi, Hitoshi; Murata, Naomichi; Egusa, Masahiko; Miyawaki, Takuya

2017-01-01

The extraction of lower wisdom teeth is often performed under general anesthesia in patients with intellectual disabilities. However, the choice of analgesics has not yet been investigated. To analyze the use of analgesics during general anesthesia for extraction including lower wisdom teeth in patients with intellectual disabilities. This research is a retrospective observational study. The study population was composed of all patients presenting for extraction of lower wisdom teeth under ambulatory general anesthesia in the clinic of Special Needs Dentistry in Okayama University Hospital from April 2011 to March 2016. The distribution of the combination of analgesics and the relationship between the use of analgesics and the type of extraction were investigated. One hundred and twelve cases were enrolled in this study. Intravenous injections of flurbiprofen, acetaminophen and betamethasone were used in 96 (85.7%), 12 (10.7%) and 26 cases (23.2%), respectively. Flurbiprofen is a non-steroid anti-inflammatory drugs (NSAIDs). Acetaminophen is an old analgesic, but an injection of acetaminophen is new, which was released in 2013 in Japan. And betamethasone is not an analgesic, but a steroid. Betamethasone was used in combination with other analgesics, and was used at a higher dose in a case in which four wisdom teeth were extracted. Flurbiprofen was the main analgesic used for extraction of wisdom teeth under general anesthesia in patients with intellectual disabilities. Betamethasone was used to support flurbiprofen or acetaminophen for extractions of multiple wisdom teeth, with the aim of controlling swelling rather than relieving pain.

IMPACT OF FLUORIDE ON DENTAL HEALTH QUALITY.

Science.gov (United States)

Medjedovic, Eida; Medjedovic, Senad; Deljo, Dervis; Sukalo, Aziz

2015-12-01

Fluoride is natural element that strengthens teeth and prevents their decay. Experts believe that the best way to prevent cavities is the use of fluoride from multiple sources. Studies even show that in some cases, fluoride can stop already started damage of the teeth. In children younger than 6 years fluoride is incorporated into the enamel of permanent teeth, making the teeth more resistant to the action of bacterial and acids in food. The aim of this study is to determine the effects of improving the health status of teeth after six months treatment with the use of topical fluoridation 0.5% NaF, and the level and quality of the impact of treatment with chemical 0.5% NaF on the dental health of children at age from 8 to 15 years, in relation to gender and chronological age. This study included school children aged 8 to 15 years who visited health and dental services dependent in Mostar. It is obvious that after the implementation of treatment with 5% NaF by the method of topical fluoridation, health status of subjects from the experimental group significantly improved, so that at the final review 89.71% or 61 subjects of the experimental group had healthy (cured teeth), tooth with dental caries only 5.88% or 4 respondents tooth with dental caries and filling 4.41% or 3 respondents, extracted baby tooth 14.71% or 10 respondents, while for 13.24% of respondents was identified state with still unerupted teeth. Our findings are indirectly confirmed that the six-month treatment of fluoridation with 5% NaF, contributed to statistically significant improvement in overall oral health of the experimental group compared to the control group which was not treated by any dental treatment. It can be concluded that there is a statistically significant difference in the evaluated parameters of oral health of children in the control group compared to the studied parameters of oral health the experimental group of children at the final dental examination.

ERUPTION PATTERN OF PERMANENT TEETH -IN TANZANIA ...

African Journals Online (AJOL)

was visible in the oral vacity. Generally permanent teeth erupted earlier in girls than in boys. The differences were 0.1 - 0.2 years for incisors and first molars, 0.2 - 0.4 years for canines and premolars and 0.3 - 0.5 years for second molars. Except for the second premolars, mandibular teeth erupted earlier than the maxillary in ...

Methodology for Structural Calculation of Gear Teeth with Unconventional Profile

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Radicella Andrea Chiaramonte

2016-01-01

Full Text Available After having made reference to the structural analysis used in the study of gear wheel teeth, we then move on to the state of the art on the topic. We proceed to identify the boundary conditions used in the structural analysis of unconventional teeth with sides having a profile of an involute of a circle but with different pressure angles in each of the two sides. A procedure for the discretization of traditional teeth and of innovative teeth is presented and compared with the discretization obtained using current software.

Health of periodontal tissues and resorption status after orthodontic treatment of impacted maxillary canines.

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Oz, A Z; Ciger, S

2018-03-01

The aim of the present study was to evaluate the changes of incisor root resorption associated with impacted maxillary canines and health of periodontal tissues around maxillary canines erupted with orthodontic treatment. Twenty patients with a unilateral palatally impacted maxillary canine were included in the study. Cone-beam computed tomography images taken before and after orthodontic treatment were compared with the contralateral canines serving as control teeth. Root resorption was present in 10% of central and 40% of lateral incisors before treatment. After treatment, the incidence of resorption decreased. The thickness of the buccal bone surrounding the impacted canines was similar to that surrounding the contralateral canines, except in the apical area. Periodontal pocket depth and alveolar bone loss were greater for the impacted canine teeth than for the contralateral canines. Incisor root resorption associated with impacted canine teeth showed signs of repair after orthodontic treatment. Slight differences related to periodontal health were found between the previously impacted teeth and contralateral canine teeth.

White light scanner-based repeatability of 3-dimensional digitizing of silicon rubber abutment teeth impressions.

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Jeon, Jin-Hun; Lee, Kyung-Tak; Kim, Hae-Young; Kim, Ji-Hwan; Kim, Woong-Chul

2013-11-01

The aim of this study was to evaluate the repeatability of the digitizing of silicon rubber impressions of abutment teeth by using a white light scanner and compare differences in repeatability between different abutment teeth types. Silicon rubber impressions of a canine, premolar, and molar tooth were each digitized 8 times using a white light scanner, and 3D surface models were created using the point clouds. The size of any discrepancy between each model and the corresponding reference tooth were measured, and the distribution of these values was analyzed by an inspection software (PowerInspect 2012, Delcamplc., Birmingham, UK). Absolute values of discrepancies were analyzed by the Kruskal-Wallis test and multiple comparisons (α=.05). The discrepancy between the impressions for the canine, premolar, and molar teeth were 6.3 µm (95% confidence interval [CI], 5.4-7.2), 6.4 µm (95% CI, 5.3-7.6), and 8.9 µm (95% CI, 8.2-9.5), respectively. The discrepancy of the molar tooth impression was significantly higher than that of other tooth types. The largest variation (as mean [SD]) in discrepancies was seen in the premolar tooth impression scans: 26.7 µm (95% CI, 19.7-33.8); followed by canine and molar teeth impressions, 16.3 µm (95% CI, 15.3-17.3), and 14.0 µm (95% CI, 12.3-15.7), respectively. The repeatability of the digitizing abutment teeth's silicon rubber impressions by using a white light scanner was improved compared to that with a laser scanner, showing only a low mean discrepancy between 6.3 µm and 8.9 µm, which was in an clinically acceptable range. Premolar impression with a long and narrow shape showed a significantly larger discrepancy than canine and molar impressions. Further work is needed to increase the digitizing performance of the white light scanner for deep and slender impressions.

Fracture resistance of endodontically treated teeth restored with Zirconia filler containing composite core material and fiber posts.

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Jeaidi, Zaid Al

2016-01-01

To assess the fracture resistance of endodontically treated teeth with a novel Zirconia (Zr) nano-particle filler containing bulk fill resin composite. Forty-five freshly extracted maxillary central incisors were endodontically treated using conventional step back preparation and warm lateral condensation filling. Post space preparation was performed using drills compatible for fiber posts (Rely X Fiber Post) on all teeth (n=45), and posts were cemented using self etch resin cement (Rely X Unicem). Samples were equally divided into three groups (n=15) based on the type of core materials, ZirconCore (ZC) MulticCore Flow (MC) and Luxacore Dual (LC). All specimens were mounted in acrylic resin and loads were applied (Universal testing machine) at 130° to the long axis of teeth, at a crosshead speed of 0.5 mm/min until failure. The loads and the site at which the failures occurred were recorded. Data obtained was tabulated and analyzed using a statistical program. The means and standard deviations were compared using ANOVA and Multiple comparisons test. The lowest and highest failure loads were shown by groups LC (18.741±3.02) and MC (25.16±3.30) respectively. Group LC (18.741±3.02) showed significantly lower failure loads compared to groups ZC (23.02±4.21) and MC (25.16±3.30) (pcomposite cores was comparable to teeth restored with conventional Zr free bulk fill composites. Zr filled bulk fill composites are recommended for restoration of endodontically treated teeth as they show comparable fracture resistance to conventional composite materials with less catastrophic failures.

Surgically facilitated experimental movement of teeth : systematic review

NARCIS (Netherlands)

Liem, A. M. L.; Hoogeveen, E. J.; Jansma, J.; Ren, Y.

Several surgical techniques based on corticotomy and dental distraction have been developed to improve the movement of teeth and reduce the duration of orthodontic treatment. In this systematic review we have critically assessed published studies on the experimental movement of teeth to find out

The history of Latin teeth names.

Science.gov (United States)

Šimon, František

2015-01-01

This paper aims to give an account of the Latin naming of the different types of teeth by reviewing relevant historical and contemporary literature. The paper presents etymologies of Latin or Greek teeth names, their development, variants and synonyms, and sometimes the names of their authors. The Greek names did not have the status of official terms, but the Latin terms for particular types of teeth gradually established themselves. Names for the incisors, canines and molars are Latin calques for the Greek ones (tomeis, kynodontes, mylai), dens serotinus is an indirect calque of the Greek name (odús) opsigonos, and the term pre-molar is created in the way which is now common in modern anatomical terminology, using the prefix prae- = pre and the adjective molaris. The Latin terms dentes canini and dentes molares occur in the Classical Latin literature, the term (dentes) incisivi is found first time in medieval literature, and the terms dentes premolares and dens serotinus are modern-age ones.

Shaping Cutter Original Profile for Fine-module Ratchet Teeth Cutting

Science.gov (United States)

Sharkov, O. V.; Koryagin, S. I.; Velikanov, N. L.

2018-03-01

The methods for determining geometric characteristics of a theoretical original profile of the cutter for cutting ratchet teeth with a module of 0.3–1.0 mm are considered in the article. Design models describing the shaping process of cutting edges of cutter teeth are developed. Systems of expressions for determining coordinates of the points of front and back edges of cutter teeth; the workpiece angles of rotation during the cutting process; the minimum cutter radius are received. The basic data when using the proposed technique are: radii of circumferences passing through cavities of cutter teeth and external cut teeth; the gradient angle and length of straight section of the front edge of a cut tooth; angles of rotation of the cutter and the workpiece at the moment of shaping.

Maxillary canine impactions related to impacted central incisors: two case reports.

Science.gov (United States)

Bayram, Mehmet; Ozer, Mete; Sener, Ismail

2007-09-01

The purpose of this case report is to describe the combined surgical and orthodontic treatment of two cases with an impacted maxillary central incisor and canine in the same quadrant and to discuss the causal relationship between them. The most common causes of canine impactions are usually the result of one or more factors such as a long path of eruption, tooth size-arch length discrepancies, abnormal position of the tooth bud, prolonged retention or early loss of the deciduous canine, trauma, the presence of an alveolar cleft, ankylosis, cystic or neoplastic formation, dilaceration of the root, supernumerary teeth, and odontomas. Although impaction of the maxillary central incisor is almost as prevalent as impacted canines its etiology is different. The principal factors involved in causing the anomaly are supernumerary teeth, odontomas, and trauma. Case #1: A 10.5-year-old girl in the early mixed dentition stage presented with a chief complaint of the appearance of her anterior teeth. She had a Class I skeletal pattern and a history of trauma to the maxillary central incisors at age five with premature exfoliation. Radiographs revealed an impacted upper right central incisor in the region of the nasal floor, delayed eruption of the maxillary permanent central incisor, and the adjacent lateral incisor was inclined toward the edentulous space. Treatment was done in two stages consisting of surgical exposure and traction of the impacted central incisor and fixed orthodontic treatment. Case #2: An 11.5-year-old girl presented for orthodontic treatment with the chief complaint of an unerupted tooth and the appearance of her upper anterior teeth. She was in the late mixed dentition period with a Class III skeletal pattern along with an anterior cross-bite with some maxillary transverse deficiency. The maxillary right canine and central incisor were absent, but the maxillary right deciduous canine was still present. Treatment included arch expansion followed by

Cone beam computed tomography findings of impacted upper canines

Energy Technology Data Exchange (ETDEWEB)

Da Silva Santos, Ludmilla Mota [Dept. of Endodontics, Aracatuba Dental School, Paulista State University, Aracatuba(Brazil); Bastos, Luana Costa; Da Silva, Silvio Jose Albergaria; Campos, Paulo Sergio Flores [School of Dentistry, Federal University of Bahia, Salvador (Brazil); Oliveira Santos, Christiano [Dept. of Stomatology, Oral Public Health, and Forensic Dentistry, School of Dentistry, University of Sao Paulo, Ribeirao Preto (Brazil); Neves, Frederico Sampaio [Dept. of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba (Brazil)

2014-12-15

To describe the features of impacted upper canines and their relationship with adjacent structures through three-dimensional cone-beam computed tomography (CBCT) images. Using the CBCT scans of 79 upper impacted canines, we evaluated the following parameters: gender, unilateral/bilateral occurrence, location, presence and degree of root resorption of adjacent teeth (mild, moderate, or severe), root dilaceration, dental follicle width, and presence of other associated local conditions. Most of the impacted canines were observed in females (56 cases), unilaterally (51 cases), and at a palatine location (53 cases). Root resorption in adjacent teeth and root dilaceration were observed in 55 and 47 impacted canines, respectively. In most of the cases, the width of the dental follicle of the canine was normal; it was abnormally wide in 20 cases. A statistically significant association was observed for all variables, except for root dilaceration (p=0.115) and the side of impaction (p=0.260). Root resorption of adjacent teeth was present in most cases of canine impaction, mostly affecting adjacent lateral incisors to a mild degree. A wide dental follicle of impacted canines was not associated with a higher incidence of external root resorption of adjacent teeth.

Cone beam computed tomography findings of impacted upper canines

International Nuclear Information System (INIS)

Da Silva Santos, Ludmilla Mota; Bastos, Luana Costa; Da Silva, Silvio Jose Albergaria; Campos, Paulo Sergio Flores; Oliveira Santos, Christiano; Neves, Frederico Sampaio

2014-01-01

To describe the features of impacted upper canines and their relationship with adjacent structures through three-dimensional cone-beam computed tomography (CBCT) images. Using the CBCT scans of 79 upper impacted canines, we evaluated the following parameters: gender, unilateral/bilateral occurrence, location, presence and degree of root resorption of adjacent teeth (mild, moderate, or severe), root dilaceration, dental follicle width, and presence of other associated local conditions. Most of the impacted canines were observed in females (56 cases), unilaterally (51 cases), and at a palatine location (53 cases). Root resorption in adjacent teeth and root dilaceration were observed in 55 and 47 impacted canines, respectively. In most of the cases, the width of the dental follicle of the canine was normal; it was abnormally wide in 20 cases. A statistically significant association was observed for all variables, except for root dilaceration (p=0.115) and the side of impaction (p=0.260). Root resorption of adjacent teeth was present in most cases of canine impaction, mostly affecting adjacent lateral incisors to a mild degree. A wide dental follicle of impacted canines was not associated with a higher incidence of external root resorption of adjacent teeth.

The aesthetic treatment for anterior teeth with lost crown by endorestoration

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Nanik Zubaidah

2009-06-01

Full Text Available Background: The aesthetic has an important role in social life, especially the anterior teeth. The aesthetic abnormality of anterior teeth i.e. discoloration, malpotition or the anterior teeth with crown damage for more than one third or all part of crown is lost due to caries or other causes, will influence its appearance especially during smile. Purpose: The aim of this case report, therefore, is to show how teeth with clinical crown lost or only the root left still can be treated by endorestoration treatment in order to reconstruct the shape and function of the teeth similar to the original ones. Case: Female 52 years old with the lost crown of anterior teeth. The patient did not want her teeth to be extracted. Case Management: The abnormality of these teeth are still able to be reconstructed by endorestoration i.e. endodontic treatment with post and core insertion in the root canal will increase its retention and recovery by the porcelain crown fused to metal to recover the original formation and aesthetic and thus has the normal refunction. The treatment, it improve the confidence of the patient, and also can function normally. The patient did not feel pain. Ronsenography showed the periapical lesion diminished, the neighbor gingival was going better in both function and color. Conclusion: Endorestoration treatment on the anterior teeth with lost crown could recover the normal function, dental aesthetic and self confidence.

Demineralization–remineralization dynamics in teeth and bone

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Abou Neel EA

2016-09-01

Full Text Available Ensanya Ali Abou Neel,1–3 Anas Aljabo,3 Adam Strange,3 Salwa Ibrahim,3 Melanie Coathup,4 Anne M Young,3 Laurent Bozec,3 Vivek Mudera4 1Division of Biomaterials, Operative Dentistry Department, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 2Biomaterials Department, Faculty of Dentistry, Tanta University, Tanta, Egypt; 3Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, UK; 4UCL Institute of Orthopaedics and Musculoskeletal Sciences, Royal National Orthopaedic Hospital, Stanmore, London, UK Abstract: Biomineralization is a dynamic, complex, lifelong process by which living organisms control precipitations of inorganic nanocrystals within organic matrices to form unique hybrid biological tissues, for example, enamel, dentin, cementum, and bone. Understanding the process of mineral deposition is important for the development of treatments for mineralization-related diseases and also for the innovation and development of scaffolds. This review provides a thorough overview of the up-to-date information on the theories describing the possible mechanisms and the factors implicated as agonists and antagonists of mineralization. Then, the role of calcium and phosphate ions in the maintenance of teeth and bone health is described. Throughout the life, teeth and bone are at risk of demineralization, with particular emphasis on teeth, due to their anatomical arrangement and location. Teeth are exposed to food, drink, and the microbiota of the mouth; therefore, they have developed a high resistance to localized demineralization that is unmatched by bone. The mechanisms by which demineralization–remineralization process occurs in both teeth and bone and the new therapies/technologies that reverse demineralization or boost remineralization are also scrupulously discussed. Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties

Guidelines on the use of space maintainers following premature loss of primary teeth.

Science.gov (United States)

Brothwell, D J

1997-11-01

To formulate evidence-based guidelines on the appropriate use of space maintaining appliances to prevent or reduce the severity of malocclusion in the permanent dentition following the premature loss of primary teeth. Placement of lingual arch, palatal arch, band-loop, crown-loop, and intra-alveolar space maintainers. Reduced prevalence or severity of space loss in the primary or mixed dentition, reduced prevalence or severity of malocclusion in the permanent dentition measured as significant changes in: crowding, ectopic eruption, impacted teeth, Angle's class II or III occlusion, crossbite, deep overbite, deep overjet, or midline shift. Articles published from 1966 to 1996, located though Medline searches. Only clinical trials, cohort studies, case-control studies, or large case series were considered. Relevant clinical findings were evaluated and categorized using evidence-based methods and values established by the Canadian Task Force on the Periodic Health Examination. A recommendation was developed for the use of space maintainers. The potential benefits of using space maintaining appliances include reduced prevalence or severity of: crowding, ectopic eruption, tooth impaction, crossbite, excessive overbite and overjet, and poor molar relationship. Other advantages include the potential for considerable cost savings by reducing the need for future orthodontic treatment. The potential disadvantages of using space maintaining appliances include soft tissue impingement, interference with eruption of adjacent teeth, pain, plaque accumulation, caries, and broken, dislodged or lost appliances. There is poor evidence to recommend for or against the use of space maintainers to prevent or reduce the severity of malocclusion in the permanent dentition (see Table 1, Recommendation C) Decisions regarding the use of space maintainers must therefore be guided by factors other than scientific evidence.

Rare association of hyper IgE syndrome with cervical rib and natal teeth

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Roshan Anupama

2009-01-01

Full Text Available Hyper IgE syndrome (HIES is a rare immunodeficiency syndrome characterized by a triad of cutaneous abscesses, mostly caused by Staphylococus aureus; pneumonia; and raised IgE levels. Nonimmunological associations include course facial features, multiple bone fractures, joint hyperextensibility, and retained primary dentition. Patients require long-term antibiotic therapy. We report here a classical case of HIES with rare associations of natal teeth, bilateral cervical ribs, and conductive deafness. The patient was being treated with monteleukast and dapsone.

Is biologic width of anterior and posterior teeth similar?

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Amir Alireza Rasouli Ghahroudi

2014-09-01

Full Text Available The biologic width (BW includes attached epithelial cells and connective tissue attachment complex being very important in the periodontal health during prosthetic treatments as invading this zone can cause bone resorption and gingival recession. The present study investigated biologic width values in the normal periodontium in anterior and posterior teeth. 30 patients that referred from restorative department to periodontics department of Tehran University of medical sciences who need crown lengthening procedure on their teeth with no history of orthodontic, prosthodontic and periodontal treatment were randomly enrolled in this cross-sectional trial. Sulcus depths (SD as well as the distance between free gingival margin and the bone crest (FB of anterior and posterior teeth were measured by UNC-15 probe and compared. periodontium thickness was also assessed. The data were subjected to Student t test. Mean BW in the 43 anterior and 47 posterior teeth was measured and not significantly different (1.4651±0.39 mm vs. 1.6312±0.49 mm was observed; however, BW was significantly more in the teeth with thick periodontium compared to those with thin periodontium (1.703±0.5 vs. 1.408±0.35; P=0.002. BW not only is different in individuals but also could be dissimilar in different teeth and should be calculated independently prior to restorative treatments.

Rotary endodontics in primary teeth - A review.

Science.gov (United States)

George, Sageena; Anandaraj, S; Issac, Jyoti S; John, Sheen A; Harris, Anoop

2016-01-01

Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the "gold-standard" over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel-titanium (Ni-Ti) rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel-titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed.

[Reinforcement for overdentures on abutment teeth].

Science.gov (United States)

Osada, Tomoko

2006-04-01

This study investigated the effect of the position of reinforcement wires, differences in artificial teeth, and framework designs on the breaking strength of overdentures. The basal surfaces of composite resin teeth and acrylic resin teeth were removed using a carbide bur. A reinforcement wire or a wrought palatal bar was embedded near the occlusal surface or basal surface. Four types of framework structures were designed : conventional skeleton (skeleton), housing with skeleton (housing), housing plus short metal backing (metal backing), and housing plus long metal backing (double structure). After the wires, bars, and frameworks were sand-blasted with 50 microm Al(2)O(3) powder, they were primed with a metal primer and embedded in a heat-polymerized denture base resin. The breaking strengths (N) and maximum stiffness (N/mm) of two-week aged (37 degrees C) specimens were measured using a bending test (n=8). All data obtained at a crosshead speed of 2.0 mm/min were analyzed by ANOVA/Tukey's test (alpha=0.01). There were no statistical differences between the two kinds of artificial teeth (p>0.01). The wrought palatal bar had significantly higher strength than the reinforcement wire (p0.01). The breaking strength and maximum stiffness of the double structure framework were significantly greater (poverdentures were influenced by the size and position of the reinforcement wires. Double structure frameworks are recommended for overdentures to promote a long-term prognosis without denture breakage.

The impact of comorbidity on mortality in multiple myeloma

DEFF Research Database (Denmark)

Gregersen, Henrik; Vangsted, Annette Juul; Abildgaard, Niels

2017-01-01

To describe the prevalence of comorbidity and its impact on survival in newly diagnosed multiple myeloma patients compared with population controls. Cases of newly diagnosed symptomatic multiple myeloma during the 2005-2012 period were identified in the Danish National Multiple Myeloma Registry....... For each myeloma patient, 10 members of the general population matched by age and sex were chosen from the national Civil Registration System. Data on comorbidity in the myeloma patients and the general population comparison cohort were collected by linkage to the Danish National Patient Registry (DNPR......). Cox proportional hazards regression models were used to evaluate the prognostic significance of comorbidity. The study included 2190 cases of multiple myeloma and 21,900 population controls. The comorbidity was increased in multiple myeloma patients compared with population controls, odds ratio (OR) 1...

An unusual case of idiopathic multiple invasive cervical resorption

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Sathya Prakash Reddy Kesary

2014-01-01

Full Text Available Invasive cervical resorption is a rare form of root resorption, characterized by destruction of the cervical region of teeth resulting from the action of tooth resorbing cells. Being an asymptomatic condition, it is often discovered on routine radiographic examination. This multifactorial disease process can most commonly occur as a sequel to orthodontic treatment, dental trauma, bleaching procedures, and less commonly, as an outcome of segmental orthognathic surgery, periodontal root planning, tetracycline conditioning of the root canal, bruxism, transplantation of tooth, guided tissue regeneration, cementoenamel disjunction. In the absence of these predisposing factors, it can be labeled as ′idiopathic multiple cervical resorption′. This article describes the case of a medically fit Indian male, who displayed idiopathic invasive cervical resorption in multiple teeth.

Man, nutrition and mobility: A comparison of teeth and bone from the Medieval era and the present from Pb and Sr isotopes

International Nuclear Information System (INIS)

Aberg, G.; Stray, H.; Fosse, G.

1998-01-01

Naturally occurring isotopic systems, such as strontium (Sr) and lead (Pb), are very useful for characterizing different sources and to produce background information. Norwegian teeth from the Medieval era have 206 Pb/ 204 Pb ratios between 18.8 and 18.2, in comparison with present day ratios of between 18.0 and 17.6 showing the impact of Pb from modern industrialization and from traffic. Sr analyses of Medieval teeth show that an individual living in a coastal town on the west coast of Norway can easily be distinguished from one in a rural area at that time. The Sr signature shows that Medieval people lived on local products while present people to a greater degree live on imported or domestic industrially processed food. Medieval and modern teeth from one site give similar Pb signatures and concentrations indicating no increase in pollution over time. However, the impact of industrial pollution can be seen from Pb analyses on contemporary teeth, so that the method can be used to monitor emission of heavy metals from local industry. Whilst the Pb and Sr natural isotopic systems individually provide valuable information, a combination of the two techniques is a very powerful tool in environmental and archaeological research. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

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.

The management of over closured anterior teeth due to attrition

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Eha Djulaeha

2009-12-01

Full Text Available Background: Tooth is the hardest tissue in human body, that can be injured because of attrition process. For old people, denture attrition process is caused by psysiological process relating with the mastication function which also supported by some bad habits such an bruxism, premature contact, and consuming habit of abrasive food. Attrition or abrasion can also be happened with patien’t dentition who does not have teeth subtutition for long time due the lost of their maxillary as well as mandibulary. The pasient will loose their vertical dimension of occlusion, injure, and the lower jaw becomes over closed which is called over closure. Purpose: This article reported the management of over closured anterior teeth due to attrition. Case: a seventy six year old woman patient came to Prosthodontic Clinic in Faculty of Dentistry, Airlangga University, to rehabilitate her upper and lower severe attrited anterior teeth and her posterior teeth. The patient has experienced of wearing acrylic removable mandibular partial denture ten years ago. Unfortunaly, the denture was uncomfortable, and she did not wear it anymore since five years ago. Case management: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually. The treatment is then followed by the increasing of the height of the anterior teeth by lengthening the crown teeth of upper jaw with 12 units of span bridge and the acrylic removable partial denture of lower jaw. Conclusion: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually, using long span bridge and acrylic removable partial denture.

The large superpredators' teeth from Middle Triassic of Poland

Science.gov (United States)

Surmik, Dawid; Brachaniec, Tomasz

2013-09-01

An unusual large teeth, finding from time to time in marine sediments of Muschelkalk, Silesia, Poland indicate the superpredators occurrence. According to size and morphological features the teeth are similar to archosaurs or giant marine reptiles.

Radiographic studies on the development of cheek teeth in donkeys

International Nuclear Information System (INIS)

Misk, N.A.; Seilem, S.M.

1997-01-01

The current study was carried out on 60 head specimens of donkeys in addition to five living animals. Specimens and animal's heads were radiographed. Radiographs were grouped from 1 day up to 15 years of age. Recorded data included the following points: 1) Time of radiographic appearance and different developmental stages of deciduous and permanent cheek teeth. 2) Length of deciduous cheek teeth from birth to shedding. 3) Length of permanent cheek teeth from birth to senility. 4) Body and root length from age 5 up to 15 years of age. 5) Wolf teeth: occurrence, time of eruption and shedding. All results were documented and illustrated in tables and photographs

Remarkable resilience of teeth.

Science.gov (United States)

Chai, Herzl; Lee, James J-W; Constantino, Paul J; Lucas, Peter W; Lawn, Brian R

2009-05-05

Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel-dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by "stress shielding" from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet.

Periapical and endodontic status of permanent teeth in patients with hypophosphatemic rickets

DEFF Research Database (Denmark)

Andersen, Mette Guldbæk; Beck-Nielsen, Signe; Haubek, Dorte

2012-01-01

panoramic radiograph, which was scored for endodontically affected teeth (i.e. teeth with periapical radiolucencies and/or endodontically treated teeth). A total of 52 patients (age range: 5·7-74·5 years; 17 males and 35 females) were included. HR patients were characterised by a high number...... genetically. The aim of the present study was to describe the periapical and endodontic status of permanent teeth in patients with genetically and/or biochemically confirmed HR. The patients were recruited from a medical study on HR patients. The patients underwent a dental examination including a digital...... of endodontically affected teeth (mean: 4·2; s.d.: 5·0). The number of affected teeth rose significantly with age (P ...

Comparative analysis of human and bovine teeth: radiographic density

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Jefferson Luis Oshiro Tanaka

2008-12-01

Full Text Available Since bovine teeth have been used as substitutes for human teeth in in vitro dental studies, the aim of this study was to compare the radiographic density of bovine teeth with that of human teeth to evaluate their usability for radiographic studies. Thirty bovine and twenty human teeth were cut transversally in 1 millimeter-thick slices. The slices were X-rayed using a digital radiographic system and an intraoral X-ray machine at 65 kVp and 7 mA. The exposure time (0.08 s and the target-sensor distance (40 cm were standardized for all the radiographs. The radiographic densities of the enamel, coronal dentin and radicular dentin of each slice were obtained separately using the "histogram" tool of Adobe Photoshop 7.0 software. The mean radiographic densities of the enamel, coronal dentin and radicular dentin were calculated by the arithmetic mean of the slices of each tooth. One-way ANOVA demonstrated statistically significant differences for the densities of bovine and human enamel (p 0.05. Based on the results, the authors concluded that: a the radiographic density of bovine enamel is significantly higher than that of human enamel; b the radiodensity of bovine coronal dentin is statistically lower than the radiodensity of human coronal dentin; bovine radicular dentin is also less radiodense than human radicular dentin, although this difference was not statistically significant; c bovine teeth should be used with care in radiographic in vitro studies.

Influence of trace elements on fluoride uptake by teeth

Energy Technology Data Exchange (ETDEWEB)

Chaudhri, M A [Austin Hospital, Heidelberg (Australia). Dept. of Medical Physics; Melbourne Univ., Austin (Australia). Dept. of Medicine); Crawford, A [Melbourne Univ., Parkville (Australia). School of Physics

1981-03-01

To investigate the effect of various trace elements on fluoride uptake by teeth, the concentrations of F and other trace elements have been simultaneously determined in different regions of the teeth from children of South Australia. Teeth cross sectioned along the median plane have been used in these investigations, and their inside enamel, dentine and amelodentinal junctions investigated separately for the trace elemental composition. Fluoride has been determined by observing the 6-7 MeV gammas for the /sup 19/F(p,..cap alpha gamma..)/sup 16/O reaction, C by activation through the /sup 12/C(/sup 3/He,n)/sup 14/O reaction, while other trace elements have been measured by the thick target PIXE technique. Linear correlation coefficients have been calculated between the F concentrations in teeth and those of other trace elements observed. Fluoride is found to correlate best with C, Cu and Pb, poorly with Fe, Sr, Ni and Ag, while with Br and Zn it has-ve coefficients. Student's t-test has been applied to the data to examine the significance of the variation of Fand other trace elements amongst different dental tissues from healthy and diseased teeth.

Color stability of different denture teeth materials: an in vitro study.

Science.gov (United States)

Mutlu-Sagesen, L; Ergün, G; Ozkan, Y; Bek, B

2001-09-01

The aim of this in vitro study was to compare the color stability of commercially available porcelain, reinforced acrylic, and conventional acrylic denture teeth materials used in removable prostheses. Two brands of porcelain (Unilux-Enta Lactona-Holland and Vivoperl-Ivoclar-Liechtenstein), 2 brands of reinforced acrylic (Optodent-Bayer-Germany and Ivolek-Ivoclar-Liechtenstein), and 2 brands of conventional acrylic (Isodent-Güney Diş Deposu-Turkey and Samed-Turkey), were made, for a total of 6 different denture teeth groups. Denture teeth were subjected to 3 staining solutions (filtered coffee, tea, and cola) and distilled water. From each group of denture teeth, 4 sets of maxillary anterior denture teeth were immersed in each of the 4 solutions. The color values of denture teeth were measured colorimetrically with the Gardner XL 20 Tristimulus Colorimeter (Gardner Lab. Inc., Bethesda, Maryland, USA). Color changes were characterized in the CIEL*a*b* color space. Color change values were determined after 1 day, 1 week, 2 weeks, and 4 weeks. The color difference values were calculated and then evaluated by two-way ANOVA statistically. The filtered coffee solution was found to be more chromogenic than the other 2 staining solutions, while porcelain denture teeth materials were more color stable. Assuming the color change of deltaE* < 1.0 as a discernible limit and deltaE* = 3.3 as an acceptable value, the filtered coffee, tea, and cola had slight staining effects on all 6 groups of denture teeth.

In vitro investigation of heat transfer phenomenon in human immature teeth.

Science.gov (United States)

Talebi, Maryam; Moghimi, Sahar; Shafagh, Mina; Kalani, Hadi; Mazhari, Fatemeh

2014-01-01

Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU). Materials and methods. This study was performed on the second mandibular premolars. This experimental investiga-tion was carried out for recording temperature variations of different sites of tooth and two dimensional finite element models were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the model validation phase. Results. Overall, thermal stimulation for 30 seconds with a low-intensity LED LCU increased the temperature from 28°C to 38°C in IIT (intact immature tooth) and PIT (cavity-prepared immature tooth). When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C. The results of the experimental tests and mathematical modeling illustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Conclusion. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are required to determine thermal conductivity of immature teeth.

Distribution of lead in teeth

Energy Technology Data Exchange (ETDEWEB)

Fremlin, J H; Tanti-Wipawin, W [Birmingham Univ. (UK). Dept. of Physics

1976-07-01

There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an ..cap alpha.. emitter, half-life 8 d. These ..cap alpha.. particles can be recorded by a plastic solid-state track detector.

Distribution of lead in teeth

International Nuclear Information System (INIS)

Fremlin, J.H.; Tanti-Wipawin, W.

1976-01-01

There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an α emitter, half-life 8 d. These α particles can be recorded by a plastic solid-state track detector. (U.K.)

Orthodontic treatment of a complete transposed impacted maxillary canine

Directory of Open Access Journals (Sweden)

Pi-Huei Liu

2015-03-01

Full Text Available Tooth transposition is a positional interchange of two adjacent teeth. Transposition most often occurs at maxillary canine. Moving transposed teeth to their normal positions is challenging because this requires bodily movement and translation of one tooth to pass another. This procedure may cause damage to the teeth or supporting structures. We report a case of complete transposition of maxillary canine and lateral incisor. Transposed teeth were successfully moved orthodontically to their normal positions. Multiple mechanics were meticulously applied to achieve complete correction of the tooth positions and to minimize root resorption and/or periodontal defects of canine and lateral incisors. Factors concerning treatment planning for transposed teeth are discussed.

Single-visit or multiple-visit root canal treatment: systematic review, meta-analysis and trial sequential analysis.

Science.gov (United States)

Schwendicke, Falk; Göstemeyer, Gerd

2017-02-01

Single-visit root canal treatment has some advantages over conventional multivisit treatment, but might increase the risk of complications. We systematically evaluated the risk of complications after single-visit or multiple-visit root canal treatment using meta-analysis and trial-sequential analysis. Controlled trials comparing single-visit versus multiple-visit root canal treatment of permanent teeth were included. Trials needed to assess the risk of long-term complications (pain, infection, new/persisting/increasing periapical lesions ≥1 year after treatment), short-term pain or flare-up (acute exacerbation of initiation or continuation of root canal treatment). Electronic databases (PubMed, EMBASE, Cochrane Central) were screened, random-effects meta-analyses performed and trial-sequential analysis used to control for risk of random errors. Evidence was graded according to GRADE. 29 trials (4341 patients) were included, all but 6 showing high risk of bias. Based on 10 trials (1257 teeth), risk of complications was not significantly different in single-visit versus multiple-visit treatment (risk ratio (RR) 1.00 (95% CI 0.75 to 1.35); weak evidence). Based on 20 studies (3008 teeth), risk of pain did not significantly differ between treatments (RR 0.99 (95% CI 0.76 to 1.30); moderate evidence). Risk of flare-up was recorded by 8 studies (1110 teeth) and was significantly higher after single-visit versus multiple-visit treatment (RR 2.13 (95% CI 1.16 to 3.89); very weak evidence). Trial-sequential analysis revealed that firm evidence for benefit, harm or futility was not reached for any of the outcomes. There is insufficient evidence to rule out whether important differences between both strategies exist. Dentists can provide root canal treatment in 1 or multiple visits. Given the possibly increased risk of flare-ups, multiple-visit treatment might be preferred for certain teeth (eg, those with periapical lesions). Published by the BMJ Publishing Group Limited

X-RAY MEASUREMENTS OF IMPACTED MANDIBULAR THIRD MOLARS

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Petya G. Kanazirska

2017-03-01

Full Text Available The X-ray diagnostics is essential in case of retention of teeth. An important condition for proper treatment plan for impacted third molars of the mandible is the determination of the type of retention in the jaw in accordance with their medio-distal inclination and the space available for eruption (retromolar space. Purpose: The purpose of this article is to present an objective method for determination of the medio-distal inclination and the space for eruption of the third molars of the mandible. Materials and methods: The studied patients with impacted third molars of the mandible are 127, aged 17 through 60. They were examined with Cone-beam Computed Tomography (CBCT. On the orthopantomography, obtained after the scanning as a reconstructed image, we defined the medio-distal inclination and space for eruption of the third molars of the mandible. For this purpose, we summarized several methods. Results: The most common inclination of the third molars of the mandible with retained eruption is the medial one at 120 teeth (61.5% ± 3.5. Second in frequency is the vertical one-34 teeth (17.4% ± 2.7, followed by the distal inclination– 21 teeth (10.8% ± 2.2. With the lowest frequency are the teeth which are positioned horizontally –20 teeth (10.3% ± 2.2. Shortage of retromolar space is established for173 teeth (88.7% ± 2.3. In 22 teeth (11.3% ± 2.3 there is enough space in the jaw for eruption. Conclusion: An objective method for determination of the medio-distal inclination of the teeth and the space available for eruption is introduced for the first time in Bulgaria. By determining the inclination of impacted wisdom teeth under this methodology one can avoid the subjective factor–the seventh tooth. It is not a reference plane, because it can also be tilted or missing. With the help of the developed method the retromolar point can be determined more objectively.

Fluorescence properties of human teeth and dental calculus for clinical applications

Science.gov (United States)

Lee, Yong-Keun

2015-04-01

Fluorescent emission of human teeth and dental calculus is important for the esthetic rehabilitation of teeth, diagnosis of dental caries, and detection of dental calculus. The purposes of this review were to summarize the fluorescence and phosphorescence of human teeth by ambient ultraviolet (UV) light, to investigate the clinically relevant fluorescence measurement methods in dentistry, and to review the fluorescence of teeth and dental calculus by specific wavelength light. Dentine was three times more phosphorescent than enamel. When exposed to light sources containing UV components, the fluorescence of human teeth gives them the quality of vitality, and fluorescent emission with a peak of 440 nm is observed. Esthetic restorative materials should have fluorescence properties similar to those of natural teeth. Based on the fluorescence of teeth and restorative materials as determined with a spectrophotometer, a fluorescence parameter was defined. As to the fluorescence spectra by a specific wavelength, varied wavelengths were investigated for clinical applications, and several methods for the diagnosis of dental caries and the detection of dental calculus were developed. Since fluorescent properties of dental hard tissues have been used and would be expanded in diverse fields of clinical practice, these properties should be investigated further, embracing newly developed optical techniques.

Comparison of Calcium Hydroxide and Bioactive Glass after Direct Pulp Capping in Primary Teeth

Directory of Open Access Journals (Sweden)

R. Haghgoo

2007-12-01

Full Text Available Objective: Bioactive glass is often used as a filler material for repair of dental bone defects.In different studies osteogenic potential of this material was proved, but its dentinogenesisproperty is in doubt. The purpose of this study was to evaluate the histological pulp responses of Calcium hydroxide and Bioactive glass placed directly on exposed pulp tissues.Materials and Methods: Twenty teeth to be extracted due to orthodontic reasons were selected. These teeth were divided into two groups and treated with direct pulp capping.Calcium hydroxide was used for 10 teeth and Bioactive glass for 10 teeth. After 60 daysthe teeth were extracted and prepared for histological evaluation. Finally the data was analyzed with exact Fisher test.Results: All teeth treated with Calcium hydroxide showed inflammation. Internal resorption was seen in six teeth, abscess in five teeth and dentinal bridge in two teeth. Inflammationwas seen in three Bioactive glass samples and dentinal bridge in seven teeth, but internal resorption and abscess were not seen.Conclusion: Bioactive glass appears to be superior to Calcium hydroxide as a pulp capping agent in primary teeth.

Genome-Wide Association Study Identifies Four Loci Associated with Eruption of Permanent Teeth

Science.gov (United States)

Zhang, Hao; Shaffer, John R.; Hansen, Thomas; Esserlind, Ann-Louise; Boyd, Heather A.; Nohr, Ellen A.; Timpson, Nicholas J.; Fatemifar, Ghazaleh; Paternoster, Lavinia; Evans, David M.; Weyant, Robert J.; Levy, Steven M.; Lathrop, Mark; Smith, George Davey; Murray, Jeffrey C.; Olesen, Jes; Werge, Thomas; Marazita, Mary L.; Sørensen, Thorkild I. A.; Melbye, Mads

2011-01-01

The sequence and timing of permanent tooth eruption is thought to be highly heritable and can have important implications for the risk of malocclusion, crowding, and periodontal disease. We conducted a genome-wide association study of number of permanent teeth erupted between age 6 and 14 years, analyzed as age-adjusted standard deviation score averaged over multiple time points, based on childhood records for 5,104 women from the Danish National Birth Cohort. Four loci showed association at Peruption and were also known to influence height and breast cancer, respectively. The two other loci pointed to genomic regions without any previous significant genome-wide association study results. The intronic SNP rs7924176 in ADK could be linked to gene expression in monocytes. The combined effect of the four genetic variants was most pronounced between age 10 and 12 years, where children with 6 to 8 delayed tooth eruption alleles had on average 3.5 (95% confidence interval: 2.9–4.1) fewer permanent teeth than children with 0 or 1 of these alleles. PMID:21931568

Removable partial denture on osseointegrated implants and natural teeth.

Science.gov (United States)

Chang, Li-Ching; Wang, Jen-Chyan; Tasi, Chi-Cheng

2007-01-01

Implants have been designed to provide edentulous patients with fixed prostheses or overdentures. Recently, implant-supported fixed partial prostheses and single crowns have become successful treatment alternatives to removable and fixed partial dentures. However, few researchers have examined "removable partial dentures on implants and natural teeth". In this article, we report two patients fitted with "removable partial dentures on implants and natural teeth". The patients were satisfied with their dentures in terms of function and aesthetics. Regular follow-up visits revealed that the periodontal and peri-implant conditions were stable. There was no evidence of excessive intrusion or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs. Since the average duration of observation was about 38 months, further follow-up examinations are necessary to determine whether these dentures remain stable long-term.

Histologic Outcomes of Uninfected Human Immature Teeth Treated with Regenerative Endodontics: 2 Case Reports.

Science.gov (United States)

Nosrat, Ali; Kolahdouzan, Alireza; Hosseini, Farzaneh; Mehrizi, Ehsan A; Verma, Prashant; Torabinejad, Mahmoud

2015-10-01

A growing body of evidence exists showing the possibility of growing vital tissues in the root canal spaces of teeth with necrotic pulps and open apices. However, there is very limited histologic information regarding characteristics of tissues formed in the root canal space of human teeth after regenerative endodontics. The aim of this study was to examine clinically and histologically the outcomes of human immature teeth treated with regenerative endodontics. Two healthy birooted human maxillary first premolar teeth scheduled for extraction were included. Preoperative radiographs confirmed that these teeth had immature apices. Vitality tests showed the presence of vital pulps in these teeth. After receiving consent forms, the teeth were isolated with a rubber dam, and the pulps were completely removed. After the formation of blood clots in the canals, the teeth were covered with mineral trioxide aggregate. Four months later, the teeth were clinically and radiographically evaluated, extracted, and examined histologically. Both patients remained asymptomatic after treatment. Radiographic examination of the teeth showed signs of root development after treatment. Histologic examination of tissues growing into the root canal space of these teeth shows the presence of connective tissue, bone and cementum formation, and thickening of roots. Based on our findings, it appears that when canals of teeth with open apices are treated with regenerative endodontics, tissues of the periodontium grow into the root canals of these teeth. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

RICHMOND CROWN - FOR RESTORATION OF BADLY MUTILATED POSTERIOR TEETH : A CASE REPORT

Directory of Open Access Journals (Sweden)

Yadav

2015-07-01

Full Text Available Restoration of badly broken endodontically treated teeth is a common problem in restorative dentistry. Such teeth often require additional support from the root canal by means of a post and core restoration. In cases where tooth structure is significantly lost full coverage restorations for posterior teeth are necessary to achieve proper tooth form and function. Badly broken teeth with minimal or no crown structure require added retention and support. The Richmond crown can be a good treatment alternative for restoration of such teeth. The Richmond crown was introduced in 1878 and incorporated a threaded tube in the canal with a screw retained crown. It was later modified to eliminate the threaded tube and was redesigned as a one piece dowel and crown. This case report shows restoration of badly mutilated posterior teeth with Richmond crown.

Man, nutrition and mobility: A comparison of teeth and bone from the Medieval era and the present from Pb and Sr isotopes

Energy Technology Data Exchange (ETDEWEB)

Aberg, G.; Stray, H. [Institute for Energy Technology, Box 40, N-2007 Kjeller (Norway); Fosse, G. [Department of Anatomy and Cell Biology, University of Bergen, N-5009 Bergen (Norway)

1998-12-11

Naturally occurring isotopic systems, such as strontium (Sr) and lead (Pb), are very useful for characterizing different sources and to produce background information. Norwegian teeth from the Medieval era have {sup 206}Pb/{sup 204}Pb ratios between 18.8 and 18.2, in comparison with present day ratios of between 18.0 and 17.6 showing the impact of Pb from modern industrialization and from traffic. Sr analyses of Medieval teeth show that an individual living in a coastal town on the west coast of Norway can easily be distinguished from one in a rural area at that time. The Sr signature shows that Medieval people lived on local products while present people to a greater degree live on imported or domestic industrially processed food. Medieval and modern teeth from one site give similar Pb signatures and concentrations indicating no increase in pollution over time. However, the impact of industrial pollution can be seen from Pb analyses on contemporary teeth, so that the method can be used to monitor emission of heavy metals from local industry. Whilst the Pb and Sr natural isotopic systems individually provide valuable information, a combination of the two techniques is a very powerful tool in environmental and archaeological research. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

A retrospective study of traumatic injuries to teeth at a Nigerian ...

African Journals Online (AJOL)

Enamel‑dentine fracture was the most common type of injury, seen in 73 (38.6%) of the traumatized teeth, 5 were avulsed and 20 posterior teeth had cuspal fracture. All the cases of avulsion and most (83.3%) of root fracture presented within 1 week of injury while teeth that presented late had pulpal necrosis. 22% of the ...

In Vitro Investigation of Heat Transfer Phenomenon in Human Immature Teeth

Directory of Open Access Journals (Sweden)

Maryam Talebi

2014-12-01

Full Text Available Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp. Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU. Materials and methods. This study was performed on the second mandibular premolars. This experimental investiga-tion was carried out for recording temperature variations of different sites of tooth and two dimensional finite element mod-els were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the mod-el validation phase. Results. Overall, thermal stimulation for 30 seconds with a low-intensity LED LCU increased the temperature from 28°C to 38°C in IIT (intact immature tooth and PIT (cavity-prepared immature tooth. When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C. The results of the experimental tests and mathematical modeling il-lustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Conclusion. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are re-quired to determine thermal conductivity of immature teeth.

Ancient whales did not filter feed with their teeth.

Science.gov (United States)

Hocking, David P; Marx, Felix G; Fitzgerald, Erich M G; Evans, Alistair R

2017-08-01

The origin of baleen whales (Mysticeti), the largest animals on Earth, is closely tied to their signature filter-feeding strategy. Unlike their modern relatives, archaic whales possessed a well-developed, heterodont adult dentition. How these teeth were used, and what role their function and subsequent loss played in the emergence of filter feeding, is an enduring mystery. In particular, it has been suggested that elaborate tooth crowns may have enabled stem mysticetes to filter with their postcanine teeth in a manner analogous to living crabeater and leopard seals, thereby facilitating the transition to baleen-assisted filtering. Here we show that the teeth of archaic mysticetes are as sharp as those of terrestrial carnivorans, raptorial pinnipeds and archaeocetes, and thus were capable of capturing and processing prey. By contrast, the postcanine teeth of leopard and crabeater seals are markedly blunter, and clearly unsuited to raptorial feeding. Our results suggest that mysticetes never passed through a tooth-based filtration phase, and that the use of teeth and baleen in early whales was not functionally connected. Continued selection for tooth sharpness in archaic mysticetes is best explained by a feeding strategy that included both biting and suction, similar to that of most living pinnipeds and, probably, early toothed whales (Odontoceti). © 2017 The Authors.

Interappointment emergencies in teeth with necrotic pulps.

Science.gov (United States)

Alaçam, Tayfun; Tinaz, Ali Cemal

2002-05-01

The incidence of interappointment emergencies in symptomatic and asymptomatic teeth with necrotic pulps was evaluated, and severity of flare-ups was determined by a quantitative method using a flare-up index. There were no significant differences in the incidence of flare-ups attributable to gender, age, diameter of lesion, taking analgesics, placebos, or no medication, or preoperative symptomatic or asymptomatic tooth diagnoses (p > 0.05). There were significantly more painful flare-ups in mandibular teeth than in maxillary (p < 0.05).

Histological evaluation of the pulp in teeth from dogs with naturally occurring periodontal disease.

Science.gov (United States)

Nemec, Ana; Pavlica, Zlatko; Stiblar-Martincic, Draga; Petelin, Milan; Erzen, Damjan; Crossley, David

2007-12-01

The purpose of this investigation was to evaluate the pulp of dog teeth affected by advanced periodontal disease. Histological examination was done on demineralized teeth extracted during clinical treatment of mature, client owned small and medium-size breed dogs with either good periodontal health or with advanced naturally occurring periodontal disease. Routinely stained sections from 5 clinically normal teeth and 22 teeth with advanced periodontitis from dogs between 5 and 12-years of age were examined using light microscopy. The pulp cavities of most teeth were narrow with low cellularity and some fibrosis of the pulp. Findings specific to periodontally affected teeth included acute and chronic pulpitis, vascular congestion, and pulp necrosis. A glomus body was identified in the pulp of one tooth and areas of poorly mineralized cementum were seen in both normal and diseased teeth. Age related changes in dog teeth appear similar to those reported for man and the rat. In addition to age related changes, the pulp of dog teeth with advanced periodontal disease were frequently inflamed or necrotic. This may reflect the advanced periodontitis affecting these teeth or a mechanical effect related to excessive tooth mobility. Further study is required to determine the etiology and significance of these findings and to investigate pulp status in less severely diseased teeth.

Taking Care of Your Teeth

Science.gov (United States)

... your teeth and gums healthy. Toothpastes contain abrasives, detergents, and foaming agents. Fluoride, the most common active ... when they're eaten alone, possibly because the production of saliva, which washes away the sugar and ...

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

Science.gov (United States)

Imfeld, Thomas

2008-02-01

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

Genetic background of supernumerary teeth.

Science.gov (United States)

Subasioglu, Asli; Savas, Selcuk; Kucukyilmaz, Ebru; Kesim, Servet; Yagci, Ahmet; Dundar, Munis

2015-01-01

Supernumerary teeth (ST) are odontostomatologic anomaly characterized by as the existence excessive number of teeth in relation to the normal dental formula. This condition is commonly seen with several congenital genetic disorders such as Gardner's syndrome, cleidocranial dysostosis and cleft lip and palate. Less common syndromes that are associated with ST are; Fabry Disease, Ellis-van Creveld syndrome, Nance-Horan syndrome, Rubinstein-Taybi Syndrome and Trico-Rhino-Phalangeal syndrome. ST can be an important component of a distinctive disorder and an important clue for early diagnosis. Certainly early detecting the abnormalities gives us to make correct management of the patient and also it is important for making well-informed decisions about long-term medical care and treatment. In this review, the genetic syndromes that are related with ST were discussed.

Optimizing the Esthetics of peg-shaped teeth

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Fabia Danielle Sales da Cunha Medeiros e Silva

2008-01-01

Full Text Available In modern esthetic dentistry, recontouring peg-shaped teeth present the option of a technique for obtaining a harmonious smile. In thiscontext, the advancement of direct dental materials, such as resin composites and adhesive systems, allows this procedure to be performedsimply and efficiently, when compared with other available techniques. Thus, the aim of this report is to present a clinical case with an esthetic solution in peg-shaped lateral incisors (12 and 22. Initially, it was opted first to perform dental bleaching with a home bleaching gel (16% carbamide peroxide associated with an acetate mold duly made for this purpose. The peg-shaped teeth were recontoured with a microhybrid resin composite (shade EA1 and DA1 with the aid of a platinum guide in silicone, obtained after diagnostic waxing on the plaster model. It was concluded that the association of esthetic procedures is of the utmost importance for obtaining good looking, aligned and harmonious teeth.

RICHMOND CROWN - FOR RESTORATION OF BADLY MUTILATED POSTERIOR TEETH : A CASE REPORT

OpenAIRE

Yadav; Swetha

2015-01-01

Restoration of badly broken endodontically treated teeth is a common problem in restorative dentistry. Such teeth often require additional support from the root canal by means of a post and core restoration. In cases where tooth structure is significantly lost full coverage restorations for posterior teeth are necessary to achieve proper tooth form and function. Badly broken teeth with minimal or no crown structure require added retention and support. The Richmond crown can be a good treatmen...

Spatial and functional modeling of carnivore and insectivore molariform teeth.

Science.gov (United States)

Evans, Alistair R; Sanson, Gordon D

2006-06-01

The interaction between the two main competing geometric determinants of teeth (the geometry of function and the geometry of occlusion) were investigated through the construction of three-dimensional spatial models of several mammalian tooth forms (carnassial, insectivore premolar, zalambdodont, dilambdodont, and tribosphenic). These models aim to emulate the shape and function of mammalian teeth. The geometric principles of occlusion relating to single- and double-crested teeth are reviewed. Function was considered using engineering principles that relate tooth shape to function. Substantial similarity between the models and mammalian teeth were achieved. Differences between the two indicate the influence of tooth strength, geometric relations between upper and lower teeth (including the presence of the protocone), and wear on tooth morphology. The concept of "autocclusion" is expanded to include any morphological features that ensure proper alignment of cusps on the same tooth and other teeth in the tooth row. It is concluded that the tooth forms examined are auto-aligning, and do not require additional morphological guides for correct alignment. The model of therian molars constructed by Crompton and Sita-Lumsden ([1970] Nature 227:197-199) is reconstructed in 3D space to show that their hypothesis of crest geometry is erroneous, and that their model is a special case of a more general class of models. (c) 2004 Wiley-Liss, Inc.

Discrimination Factors and Incorporation Rates for Organic Matrix in Shark Teeth Based on a Captive Feeding Study.

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Zeichner, S S; Colman, A S; Koch, P L; Polo-Silva, C; Galván-Magaña, F; Kim, S L

Sharks migrate annually over large distances and occupy a wide variety of habitats, complicating analysis of lifestyle and diet. A biogeochemical technique often used to reconstruct shark diet and environment preferences is stable isotope analysis, which is minimally invasive and integrates through time and space. There are previous studies that focus on isotopic analysis of shark soft tissues, but there are limited applications to shark teeth. However, shark teeth offer an advantage of multiple ecological snapshots and minimum invasiveness during removal because of their distinct conveyor belt tooth replacement system. In this study, we analyze δ 13 C and δ 15 N values of the organic matrix in leopard shark teeth (Triakis semifasciata) from a captive experiment and report discrimination factors as well as incorporation rates. We found differences in tooth discrimination factors for individuals fed different prey sources (mean ± SD; Δ 13 C squid = 4.7‰ ± 0.5‰, Δ 13 C tilapia = 3.1‰ ± 1.0‰, Δ 15 N squid = 2.0‰ ± 0.7‰, Δ 15 N tilapia = 2.8‰ ± 0.6‰). In addition, these values differed from previously published discrimination factors for plasma, red blood cells, and muscle of the same leopard sharks. Incorporation rates of shark teeth were similar for carbon and nitrogen (mean ± SE; λ C = 0.021 ± 0.009, λ N = 0.024 ± 0.007) and comparable to those of plasma. We emphasize the difference in biological parameters on the basis of tissue substrate and diet items to interpret stable isotope data and apply our results to stable isotope values from blue shark (Prionace glauca) teeth to illustrate the importance of biological parameters to interpret the complex ecology of a migratory shark.

Ancient pathogen DNA in human teeth and petrous bones

DEFF Research Database (Denmark)

Margaryan, Ashot; Hansen, Henrik B.; Rasmussen, Simon

2018-01-01

pestis. Based on shotgun sequencing data, four of these five plague victims showed clearly detectable levels of Y.pestis DNA in the teeth, whereas all the petrous bones failed to produce Y.pestis DNA above baseline levels. A broader comparative metagenomic analysis of teeth and petrous bones from 10...

Baby Teeth Link Autism and Heavy Metals, NIH Study Suggests

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... Release Thursday, June 1, 2017 Baby teeth link autism and heavy metals, NIH study suggests Cross-section ... Sinai Health System Baby teeth from children with autism contain more toxic lead and less of the ...

In vitro study of heat production during power reduction of equine mandibular teeth.

Science.gov (United States)

Allen, Martin L; Baker, Gordon J; Freeman, David E; Holmes, Kenneth R; Marretta, Sandra Manfra; Scoggins, R Dean; Constable, Peter

2004-04-01

To measure the amount of heat generated during 3 methods of equine dental reduction with power instruments. In vitro study. 30 premolar and molar teeth removed from mandibles of 8 equine heads collected at an abbatoir. 38-gauge copper-constantan thermocouples were inserted into the lingual side of each tooth 15 mm (proximal) and 25 mm (distal) from the occlusal surface, at a depth of 5 mm, which placed the tip close to the pulp chamber. Group-NC1 (n = 10) teeth were ground for 1 minute without coolant, group-NC2 (10) teeth were ground for 2 minutes without coolant, and group-C2 (10) teeth were ground for 2 minutes with water for coolant. Mean temperature increase was 1.2 degrees C at the distal thermocouple and 6.6 degrees C at the proximal thermocouple for group-NC1 teeth, 4.1 degrees C at the distal thermocouple and 24.3 degrees C at the proximal thermocouple for group-NC2 teeth, and 0.8 degrees C at the distal thermocouple and -0.1 degrees C at the proximal thermocouple for group-C2 teeth. In general, an increase of 5 degrees C in human teeth is considered the maximum increase before there is permanent damage to tooth pulp. In group-NC2 teeth, temperature increased above this limit by several degrees, whereas in group-C2 teeth, there was little or no temperature increase. Our results suggest that major reduction of equine teeth by use of power instruments causes thermal changes that may cause irreversible pulp damage unless water cooling is used.

Rotary endodontics in primary teeth – A review

Science.gov (United States)

George, Sageena; Anandaraj, S.; Issac, Jyoti S.; John, Sheen A.; Harris, Anoop

2015-01-01

Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti) rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel–titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed. PMID:26792964

Rotary endodontics in primary teeth – A review

Directory of Open Access Journals (Sweden)

Sageena George

2016-01-01

Full Text Available Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel–titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed.

Resistance of Bonded Composite Restorations on Fractures of Endodontically Treated Teeth

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AR Daneshkazemi

2005-01-01

Full Text Available Introduction: This study was performed to evaluate the effect of dentine bonding agents and Glass Ionomer cement beneath composite restorations and its resistance on fractures of endodontically treated teeth. Material and Methods: Forty sound maxillary teeth were selected; ten of them for positive control, and on the rest, RCT and MOD cavity preparations were done with standard methods. Then, the teeth were divided to four groups: 1-Sound teeth for positive control. 2-Prepared without any restoration for negative control. 3-Prepared and restored with Vitrabond(3M, USA, Single bond(3M, USA and Z100(3M, USA resin composite. 4-Prepared and restored by Single bond and Z100 resin composite. Specimens were subjected to compressive load by Instron 8502 until fracture occurred. Results: Group 1 showed the highest resistance to compressive forces followed by group 4,3&2 respectively. ANOVA, t test and Chi-square tests indicated significant difference between all the groups. Conclusion: Use of dentine bonding agents and resin composite increases resistance of endodontically treated teeth to fractures more than teeth restored with sandwich of glass ionomer cements, dentine bonding agents and resin composite.

Comparison between rotary and manual instrumentation in primary teeth.

Science.gov (United States)

Crespo, S; Cortes, O; Garcia, C; Perez, L

2008-01-01

The aim of this study was to compare the efficiency in both, preparation time and root canal shape, when using the Nickel Titanium (Ni-Ti) rotary and K-Files hand instrumentation on root canal preparation of single rooted primary teeth. Sixty single rooted primary teeth were selected and divided into two equal groups: Group (I) 30 teeth instrumented with manual K-files and group (II) 30 teeth instrumented with Ni-Ti rotary files (ProFile 0.04). Instrumentation times were calculated and root canal impressions were taken with light bodied silicone in order to evaluate the shape. The data was analyzed with SPSS program using the t-test and the Chi-square test to compare their means. The preparation time with group (I) K-files was significantly higher than in group (II) rotary files (ProFile 0.04), with a p= .005. The ProFile system showed a significantly more favorable canal taper when compared to the K-files system (P= .002). The use of rotary files in primary teeth has several advantages when compared with manual K files: the efficiency in both, preparation time and root canal shape. 1. A decreased working time, that helps maintain patient cooperation by diminishing the potential for tiredness. 2. The shape of the root canal is more conical, favoring a higher quality of the root canal filling, and increasing clinical success.

Comparison of different techniques for disinfection of teeth internal space in preclinical teaching

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Tabrizizadeh M.

2009-12-01

Full Text Available "nBackground and Aim: Extracted teeth used in preclinic should be disinfected. The aim of this study was to evaluate the effects of some disinfectants on microorganisms cultured from pulp chamber of extracted teeth."nMaterials and Methods: In this experimental study 54 intact human teeth were collected. After access cavity preparation, 10 8 B. streothermophillus endospors were inoculated into pulp chamber. Then cavities were sealed with a temporary restorative material. Teeth were divided into 5 groups of 10 each. The teeth were then stored in these disinfectants: 5.25% hypochlorite sodium, 5% Microten, 5% Deconex, 2% Glutaraldehyd, and 10% Formalin for 48 hours. Two teeth were autoclaved as negative controls and two were stored in normal saline as positive controls. The teeth were then sectioned in cervical area and cultured in Trypticase Soy Broth. After three days turbidity in tubes was evaluated. Statistical analysis was done by Fisher's exact test."nResults: None of these solutions were able to prevent microorganism growth in all samples; however, Formalin was better in six cases than that of other disinfectants. Differences between these five groups were not statistically significant (P=0.384."nConclusion: Sterilization of the teeth with autoclave is the only absolute method for disinfecting the root canals of extracted teeth and disinfectants are not reliable for this purpose.

Device for congruent X-ray images of teeth

International Nuclear Information System (INIS)

Wegner, H.; Zeumer, H.

1987-01-01

This invention has to do with a device for congruent X-ray images of teeth by means of the long-tube parallel technique and the long-tube semi-angle technique. The aim is to have no disturbing lever forces in order to avoid mechanical tensions between patient and X-ray tube assembly and to achieve a true projection of teeth and jaw-bone part also under unfavourable anatomical conditions

Combined surgical and orthodontic treatment of bilaterial double teeth: a case report.

Science.gov (United States)

Pearson, A I; Willmot, D R

1995-03-01

A case of bilateral 'double teeth' is described. The patient, aged 8 at initial presentation, was unhappy with the appearance of his two abnormally large upper central incisor teeth. Endodontic treatment was carried out on both teeth followed by surgical splitting and the removal of half of each so as to leave two reasonably-shaped central incisors. Comprehensive orthodontic treatment was then carried out to align the teeth and reduce the overjet, following which the central incisors exhibited no increased mobility or any periodontal problems.

Trace element analysis of teeth from pre-Columbian population groups in Mexico

International Nuclear Information System (INIS)

Solis, C.; Oliver, A.; Andrade, E.; Macias, R.; Mansilla, J.; Chavez-Lomeli, M.E.

1999-01-01

Human teeth from pre-Columbian and recent population groups have been analyzed by PIXE. Ancient teeth corresponding to children and adults were obtained from archaeological burials located in five geographic areas of Mexico. Inter-specific and inter-site differences in the trace element contents of enamel were compared in order to get some insight into differences in diet, environmental conditions, teeth health, disease state and post mortem alteration among the co-occurring populations. For permanent teeth from adults, small variations in trace element levels were found depending on the collection site or tooth health, but for deciduous teeth from children, the concentration of elements such as Mn, Fe and Sr varied considerably. In this work, the possible sources of variation are discussed. (author)

Characterization of Coronal Pulp Cells and Radicular Pulp Cells in Human Teeth.

Science.gov (United States)

Honda, Masaki; Sato, Momoko; Toriumi, Taku

2017-09-01

Dental pulp has garnered much attention as an easily accessible postnatal tissue source of high-quality mesenchymal stem cells (MSCs). Since the discovery of dental pulp stem cells (DPSCs) in permanent third molars, stem cells from human exfoliated deciduous teeth and from supernumerary teeth (mesiodentes) have been identified as a population distinct from DPSCs. Dental pulp is divided into 2 parts based on the developing stage: the coronal pulp and the radicular pulp. Root formation begins after the crown part is completed. We performed a sequential study to examine the differences between the characteristics of coronal pulp cells (CPCs) and radicular pulp cells (RPCs) from permanent teeth, mesiodentes, and deciduous teeth. Interestingly, although we have not obtained any data on the difference between CPCs and RPCs in permanent teeth, there are some differences between the characteristics of CPCs and RPCs from mesiodentes and deciduous teeth. The MSC characteristics differed between the RPCs and CPCs, and the reprogramming efficiency for the generation of induced pluripotent stem cells was greater in RPCs than in CPCs from deciduous teeth. The proportion of CD105 + cells in CPCs versus that in RPCs varied in mesiodentes but not in permanent teeth. The results indicate that the proportion of CD105 + cells is an effective means of characterizing dental pulp cells in mesiodentes. Taken together, the stem cells in deciduous and supernumerary teeth share many characteristics, such as a high proliferation rate and an immunophenotype similar to that of DPSCs. Thus, mesiodentes accidentally encountered on radiographs by the general dental practitioner might be useful for stem cell therapy. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Surgical considerations and management of bilateral labially impacted canines

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Yu-Shan Huang

2016-06-01

Full Text Available Canines are among the most commonly impacted teeth. When a canine is positioned labially, the untoward soft-tissue responses following surgical exposure may cause unfavorable esthetic outcomes. Therefore, decision making as to the choice of a proper surgical technique to uncover labially impacted teeth is critical. This case presentation describes two different surgical approaches for two maxillary impacted canines in a 12-year-old girl. A sequential approach included a first stage of surgical exposure using apically positioned flaps and orthodontic extrusion of both impacted teeth. A successive laterally positioned flap was used for the left maxillary canine to achieve a harmonious soft-tissue contour. In this case, close monitoring and cooperation during the various treatment phases led to proper canine positioning and a successful esthetic result, with good periodontal health and functional occlusion.

Decayed and missing teeth and oral-health-related factors: predicting depression in homeless people.

Science.gov (United States)

Coles, Emma; Chan, Karen; Collins, Jennifer; Humphris, Gerry M; Richards, Derek; Williams, Brian; Freeman, Ruth

2011-08-01

The objective of the study was to determine the effect of dental health status, dental anxiety and oral-health-related quality of life (OHRQoL) upon homeless people's experience of depression. A cross-sectional survey was conducted on a sample of homeless people in seven National Health Service Boards in Scotland. All participants completed a questionnaire to assess their depression, dental anxiety and OHRQoL using reliable and valid measures. Participants had an oral examination to assess their experience of tooth decay (decayed and missing teeth). Latent variable path analysis was conducted to determine the effects of dental health status on depression via dental anxiety and OHRQoL using intensive resampling methods. A total of 853 homeless people participated, of which 70% yielded complete data sets. Three latent variables, decayed and missing teeth, dental anxiety (Modified Dental Anxiety Scale: five items) and depression (Center for Epidemiological Studies Depression Scale: two factors), and a single variable for OHRQoL (Oral Health Impact Profile total scale) were used in a hybrid structural equation model. The variable decayed and missing teeth was associated with depression through indirect pathways (total standardised indirect effects=0.44, Pdental anxiety (χ²=75.90, df=40, comparative fit index=0.985, Tucker-Lewis index=0.977, root mean square error of approximation=0.051 [90% confidence interval: 0.037-0.065]). Depression in Scottish homeless people is related to dental health status and oral-health-related factors. Decayed and missing teeth may influence depression primarily through the psychological constructs of OHRQoL and, to a lesser extent, dental anxiety. Copyright © 2010 Elsevier Inc. All rights reserved.

Tuberculate and odontoma type supernumerary teeth.

Science.gov (United States)

Tarján, Ildikó; Gyulai, Szabolcs G; Soós, Attila; Rózsa, Noémi

2005-11-01

An 8-and-a-half-year-old girl with supernumerary teeth of tuberculate and odontoma type is described. Treatment of the patient is carried out on conventional lines with a combination of surgical and orthodontic methods. The upper tuberculate type supernumerary teeth were extracted and, after surgical exposure, the upper permanent first incisors were aligned with removable appliances. After secondary dentition was completed, the lower odontoma type supernumerary tooth was removed surgically, and also the maxillary and mandibular first premolars were extracted because of severe crowding, and fixed orthodontic appliances were used to align the permanent dentition. Early diagnosis and treatment of this anomaly is necessary to avoid more serious consequences and to prevent severe orthodontic disturbances.

Effect of tumor therapeutic irradiation on the mechanical properties of teeth tissue

International Nuclear Information System (INIS)

Fraenzel, W.; Gerlach, R.; Hein, H.J.; Schaller, H.G.

2006-01-01

Tumor irradiation of the head-neck area is accompanied by the development of a so-called radiation caries in the treated patients. In spite of conservative therapeutic measures, the process results in tooth destruction. The present study investigated the effects of irradiation on the demineralization and remineralization of the dental tissue. For this purpose, retained third molars were prepared and assigned either to a test group, which was exposed to fractional irradiation up to 60 Gy, or to a non-irradiated control group. Irradiated and non-irradiated teeth were then demineralized using acidic hydroxyl-cellulose gel; afterwards the teeth were remineralized using either Bifluorid12 registered or elmex gelee registered . The nanoindentation technique was used to measure the mechanical properties, hardness and elasticity, of the teeth in each of the conditions. The values were compared to the non-irradiated control group. Irradiation decreased dramatically the mechanical parameters of enamel and dentine. In non-irradiated teeth, demineralization had nearly the same effects of irradiation on the mechanical properties. In irradiated teeth, the effects of demineralization were negligible in comparison to non-irradiated teeth. Remineralization with Bifluorid12 registered or elmex gelee registered led to a partial improvement of the mechanical properties of the teeth. The enamel was more positively affected, by remineralization than the dentine. (orig.)

Teeth and physical fitness in a community-dwelling 40 to 79-year-old Japanese population

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Inui A

2016-06-01

Full Text Available Akinari Inui,1 Ippei Takahashi,2 Kaori Sawada,2 Akimoto Naoki,2 Toshirou Oyama,1 Yoshihiro Tamura,1 Toshiyuki Osanai,1 Anna Satake,1 Shigeyuki Nakaji,2 Wataru Kobayashi1 1Department of Oral and Maxillofacial Surgery, Hirosaki University Graduate School of Medicine, 2Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki City, Aomori Prefecture, Japan Purpose: Decline in the number of teeth and physical fitness begins from 40 years of age; however, several epidemiological studies have identified relationships between oral conditions and physical performance parameters in community-dwelling elderly population. The aim of this study was to validate the relationship between the muscle mass and its function and oral conditions (number of teeth and dental occlusion after 40 years of age in a community-dwelling population in Japan.Materials and methods: The subjects comprised of 552 volunteers (198 males and 354 females, 40–79 years who participated in the Iwaki Health Promotion Project in 2013. Multiple linear regression analyses were performed with the measures of the muscle mass and its function as objective variables and the measures of the number of teeth, age, body mass index, medical history, serum albumin concentration, smoking status, habitual alcohol intake, marital status, education levels, and exercising habits as explanatory variables. The relationships between the Eichner index and the muscle mass and its function were analyzed using analysis of covariance, with adjustment for confounding factors.Results: After adjusting for confounding factors, the number of teeth was shown to be an independent risk factor for the timed 10 m walk test (in females and the skeletal muscle mass of the whole body (in males. The results also revealed that the timed 10 m walk test was significantly correlated with the Eichner index (Classes A and C in females were correlated.Conclusion: This cross-sectional study on a

Sorption of antimony on human teeth

International Nuclear Information System (INIS)

Nofal, M.; Amin, H.; Alian, G.

1997-01-01

The study of the uptake of toxic elements on human teeth represents an interesting research area, as the fate of these elements when present in the human food is of health significance. Since antimony is one of the common toxic elements and since, the chemical behaviour of antimony is similar to that of arsenic, one of the most important toxic elements commonly encountered in cases of food poisoning, it has been decided to investigate its uptake on human teeth and on other restoration materials. The radioactive tracer technique was used to evaluate the concentration of antimony sorbed on teeth. This tracer was obtained by irradiation of antimony metal in the reactor, subsequent dissolution in concentrated sulphuric acid, evaporation to dryness and making the solution 6 M in Hydrochloric acid (1). Antimony prepared in this way is in the trivalent state (Sb III). Sorption was studied in water, tea, coffee, red tea and chicken soup. The highest sorption was achieved from water and chicken soup and least sorption was noticed in case of coffee. The results are presented in the form of the depletion of the radioactivity (A) of antimony with time in presence of a tooth in water and other drinks

Rotary endodontics in primary teeth – A review

OpenAIRE

Sageena George; S. Anandaraj; Jyoti S. Issac; Sheen A. John; Anoop Harris

2016-01-01

Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti) rotary files have been developed for use in pediatric endod...

Polycarbonate crowns for primary teeth revisited: restorative options, technique and case reports.

Science.gov (United States)

Venkataraghavan, Karthik; Chan, John; Karthik, Sandhya

2014-01-01

Esthetics by definition is the science of beauty - that particular detail of an animate or inanimate object that makes it appealing to the eye. In the modern, civilized, and cosmetically conscious world, well-contoured and well-aligned white teeth set the standard for beauty. Such teeth are not only considered attractive but are also indicative of nutritional health, self esteem, hygienic pride, and economic status. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. Even though researchers have claimed that certain restorations are better than the others, particularly owing to the issues mentioned above, the search for the ideal esthetic restoration for the primary teeth continues. This paper revisits and attempts to reintroduce the full coverage restoration, namely, polycarbonate crown, for use in primary anterior teeth.

[Significance of proper oral hygiene for health condition of mouth and teeth].

Science.gov (United States)

Ljaljević, Agima; Matijević, Snezana; Terzić, Natasa; Andjelić, Jasmina; Mugosa, Boban

2012-01-01

Proper mouth and teeth hygiene has influence on the prevention of a great number of diseases and very often some of them are not related only to oral cavity. Most frequent diseases of mouth and teeth such as caries and periodontal diseases are caused, among other factors, by poor oral hygiene. They are also more frequent in young population. The aim of this study was to estimate the influence of sociodemographic characteristics and hygienic habit on oral health in children aged 11-15 years. This cross-sectional study was conducted by the dental teams in dentist surgeries in Tivat Health Center between May and September 2009. The sample consisted of patients 11 to 15 years of age. A questionnaire and dental examination of mouth and teeth were used as research instruments. The examinations were conducted in accordance with the World Health Organization methodology and criteria. The data obtained from the interviews were correlated with those obtained from the clinical examinations. The results show that the majority of respondents brush their teeth twice a day and visit the dentist once in every six months. The research also shows that 57% respondents have caries of deciduous teeth and over 63% respondents of permanent teeth. Gingivitis was found in 14% and orthodontic anomalies in 44.7% respondents. A half of respondents who brush their teeth rarely have problems with gingivitis. There is a highly statistically significant difference between the occurrence of gingivitis and the frequency of teeth brushing. There is a significant difference between mouth and oral hygiene and sex as well as other sociodemographic characteristics of respondents. The study showed the correlation between occurrence of caries and the gingivitis and frequency of teeth brushing and dental visits.

Significance of proper oral hygiene for health condition of mouth and teeth

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Ljaljević Agima

2012-01-01

Full Text Available Background/Aim. Proper mouth and teeth hygiene has influence on the prevention of a great number of diseases and very often some of them are not related only to oral cavity. Most frequent diseases of mouth and teeth such as caries and periodontal diseases are caused, among other factors, by poor oral hygiene. They are also more frequent in young population. The aim of this study was to estimate the influence of sociodemographic characteristics and hygienic habit on oral health in children aged 11-15 years. Methods. This crosssectional study was conducted by the dental teams in dentist surgeries in Tivat Health Center between May and September 2009. The sample consisted of patients 11 to 15 years of age. A questionnaire and dental examination of mouth and teeth were used as research instruments. The examinations were conducted in accordance with the World Health Organization methodology and criteria. The data obtained from the interviews were correlated with those obtained from the clinical examinations. Results. The results show that the majority of respondents brush their teeth twice a day and visit the dentist once in every six months. The research also shows that 57% respondents have caries of deciduous teeth and over 63% respondents of permanent teeth. Gingivitis was found in 14% and orthodontic anomalies in 44.7% respondents. A half of respondents who brush their teeth rarely have problems with gingivitis. There is a highly statistically significant difference between the occurrence of gingivitis and the frequency of teeth brushing. Conclusion. There is a significant difference between mouth and oral hygiene and sex as well as other sociodemographic characteristics of respondents. The study showed the correlation between occurrence of caries and the gingivitis and frequency of teeth brushing and dental visits.

In Vitro Investigation of Heat Transfer Phenomenon in Human Immature Teeth

OpenAIRE

Maryam Talebi; Sahar Moghimi; Mina Shafagh; Hadi Kalani; Fatemeh Mazhari

2014-01-01

Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU). Materials and methods. This study was performed on the second ...

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.

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

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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.

Roentgenographic observation on development and formation of the teeth irradiated by 60Co-gamma ray

International Nuclear Information System (INIS)

Kaneko, Masayuki; Chiba, Hiroshige; Akiyama, Akihiro; Kitamura, Nobuyasu; Iwamoto, Hidemitsu

1978-01-01

On a 4-year-old boy who received radiotherapy for malignant tumor in his right mandibula, development of the teeth of 3rd to the 7th in the upper left side and the 3rd to the 7th in the upper right side was observed for 8 years. In the teeth of the 3rd to the 7th in the upper left side which were in irradiated field, and the teeth, except for the teeth of the 3rd to the 6th in the upper left side which had already completed development before irradiation, showed remarkable abnormalities in the shape of the crown such as atrophy, dwarfishness, and flatness. Also the teeth of the 3rd to the 7th of the upper right side which were not in irradiated field, teeth except for the those of the 3rd to the 6th in the upper right side showed slight abnormality in the shape of the crown and root. In irradiated teeth of the 3rd to the 7th in the upper left side, development and formation of teeth were remarkably interfered so that the teeth were almost rootless. In non-irradiated teeth of the 3rd to the 7th in the upper right side atrophy, dwarfishness, and hypoplasia in width and in diameter too. In irradiated teeth of the 3rd to the 7th in the upper left side, calcification was highly advanced in comparison with that in non-irradiated teeth of the 3rd to the 7th in the upper right side or that in normal upper right side. Also in non-irradiated teeth of the 3rd in the 7th in the upper right side, calcification was slightly advanced compared with that in normal teeth. In irradiated teeth of the 3rd to the 7th in the upper left side, the eruption of the teeth was remarkably facilitated. The irradiated tooth of the 6th in the upper left side fell out early and the other teeth were seen in planted condition on the mandibula. This seemed to be due to the foreign body eliminating mechanism. (Ueda, J.)

Variations in multiple birth rates and impact on perinatal outcomes in Europe

NARCIS (Netherlands)

Heino, A.; Gissler, M.; Hindori-Mohangoo, A.D.; Blondel, B.; Klungsøyr, K.; Verdenik, I.; Mierzejewska, E.; Velebil, P.; Sól Ólafsdóttir, H.; Macfarlane, A.; Zeitlin, J.; et al.

2016-01-01

Objective. Infants from multiple pregnancies have higher rates of preterm birth, stillbirth and neonatal death and differences in multiple birth rates (MBR) exist between countries. We aimed to describe differences in MBR in Europe and to investigate the impact of these differences on adverse

Multiple ionization produced in Yb due to N-,Si- and Ti-ion impact

International Nuclear Information System (INIS)

Verma, P.

2000-01-01

Heavy ion induced inner shell ionization produces multiple vacancies in the outer shells (M, N etc.) simultaneous to vacancies in the inner-shells (viz. L-shell), which in turn create a very complicated electronic configuration. Three projectiles N 2+,3+ , Si 7+,8+ and Ti 10+,11+ ion beams having a range of 0.3 to 3.5 MeV/u were bombarded on a thin rare earth target of Yb. The recorded L X-ray spectra of Yb have been analyzed in the light of multiple ionization produced due to the heavy ion impact. The outer-shell vacancies acting as spectator vacancies cause a shift in the energy of the various L X-ray diagram lines. A comparison of the shifts in the energies of the various L X-ray transitions of Yb due to the impact of these projectiles, from standard values and that due to proton impact along with the deviation of the intensity ratios from single hole branching ratios, reveal a dependence of multiple ionization on the projectile atomic number (Z) and energy. A further comparison of the degree of multiple ionization produced in Yb, evident by the number of spectator vacancies produced due to the impact of projectiles with 7≤Z≤22 and overlapping MeV/u range lead to explicit conclusions regarding the probability of multiple vacancy production in outer shells simultaneous to a single L-shell vacancy for such projectile target combinations. (orig.)

Patterns of bone loss around teeth restored with endodontic posts

NARCIS (Netherlands)

Katsamakis, S.; Timmerman, M.; van der Velden, U.; de Cleen, M.; van der Weijden, F.

2009-01-01

Objectives: This retrospective study described the pattern of bone loss around teeth with endodontic posts in periodontitis patients, and compared it with contra-lateral teeth without posts. Material and Methods: From full-mouth radiographic surveys of 146 periodontitis patients (35 years), 194

Forensic DNA typing from teeth using demineralized root tips.

Science.gov (United States)

Corrêa, Heitor Simões Dutra; Pedro, Fabio Luis Miranda; Volpato, Luiz Evaristo Ricci; Pereira, Thiago Machado; Siebert Filho, Gilberto; Borges, Álvaro Henrique

2017-11-01

Teeth are widely used samples in forensic human genetic identification due to their persistence and practical sampling and processing. Their processing, however, has changed very little in the last 20 years, usually including powdering or pulverization of the tooth. The objective of this study was to present demineralized root tips as DNA sources while, at the same time, not involving powdering the samples or expensive equipment for teeth processing. One to five teeth from each of 20 unidentified human bodies recovered from midwest Brazil were analyzed. Whole teeth were demineralized in EDTA solution with daily solution change. After a maximum of approximately seven days, the final millimeters of the root tip was excised. This portion of the sample was used for DNA extraction through a conventional organic protocol. DNA quantification and STR amplification were performed using commercial kits followed by capillary electrophoresis on 3130 or 3500 genetic analyzers. For 60% of the unidentified bodies (12 of 20), a full genetic profile was obtained from the extraction of the first root tip. By the end of the analyses, full genetic profiles were obtained for 85% of the individuals studied, of which 80% were positively identified. This alternative low-tech approach for postmortem teeth processing is capable of extracting DNA in sufficient quantity and quality for forensic casework, showing that root tips are viable nuclear DNA sources even after demineralization. Copyright © 2017 Elsevier B.V. All rights reserved.

Radiation doses for X-ray diagnosis teeth in dental medicine

International Nuclear Information System (INIS)

Direkov, Lyubomir

2009-01-01

X-rays are the first ionizing radiation, which are applied in medicine for diagnostic radiology and X-ray therapy. While in the beginning they are mainly used for X-ray photos of the chest /lungs and in severe fractures of the limbs, then in recent years they are widely applied in diagnostics of teeth in dental medicine. Considering that caries is a widespread disease, both in children and adults, and it requires repeated x-ray photographs of the damaged teeth for the individual, the total radiation doses, which reflect on people from the X-rays are at high values. In order to reduce external exposure to other organs /mainly thyroid gland/ by X-ray pictures of teeth, it should be used with special lead aprons with large coefficient of reduction. Keywords: doses of radiation, X-ray machines, dental, x-ray pictures of teeth, protection sources

Tooth development in a model reptile: functional and null generation teeth in the gecko Paroedura picta

Czech Academy of Sciences Publication Activity Database

Zahradníček, Oldřich; Horáček, I.; Tucker, A. S.

2012-01-01

Roč. 221, č. 3 (2012), s. 195-208 ISSN 0021-8782 R&D Projects: GA ČR(CZ) GAP305/12/1766 Grant - others:GA AV ČR(CZ) KJB601110910 Program:KJ Institutional research plan: CEZ:AV0Z50390703 Institutional support: RVO:68378041 Keywords : cusps * gecko * null generation teeth Subject RIV: EA - Cell Biology Impact factor: 2.357, year: 2012

Regional early development and eruption of permanent teeth: case report.

Science.gov (United States)

Al Mullahi, A M; Bakathir, A; Al Jahdhami, S

2017-02-01

Early development and eruption of permanent teeth are rarely reported in scientific literature. Early eruption of permanent teeth has been reported to occur due to local factors such as trauma or dental abscesses in primary teeth, and in systemic conditions. Congenital diffuse infiltrating facial lipomatosis (CDIFL) is a rare condition that belongs to a group of lipomatosis tumours. In this disorder, the mature adipocytes invade adjacent soft and hard tissues in the facial region. Accelerated tooth eruption is one of the dental anomalies associated with CDIFL. A 3-year-old boy presented with a swelling of the lower lip localised early development and eruption of permanent teeth and dental caries involving many primary teeth. The planned treatment included biopsy of the swollen lower lip to confirm the diagnosis, surgical reduction and reconstruction of lip aesthetics. The management of the carious primary teeth included preventative and comprehensive dental care and extractions. These procedures were completed under general anaesthesia due to the child's young age and poor cooperation. The lip biopsy showed features of CDIFL such as the presence of infiltrating adipose tissue, prominent number of nerve bundles and thickened vessels. The high recurrence rate of CDIFL mandates long-term monitoring during the facial growth period of the child. Follow-up care by the paediatric dentist and maxillofacial surgeon has been required to manage all aspects of this congenital malformation. This rare disorder has many implications affecting child's facial aesthetics, psychological well being, developing occlusion and risk of dental caries. A multi-disciplinary approach is needed for management of this condition.

[Observation of osteoclasts on the root surface during human deciduous teeth resorption].

Science.gov (United States)

Bao, Xiang-jun; Liang, Xing; Chen, Ming; Wang, Hang; Xie, Zhi-gang; Yang, Xiao-yu

2004-08-01

To observe osteoclasts on the resorbing surface of human deciduous teeth. After fixing the collected deciduous teeth, we prepared the tooth slices without decalcification, treated them with HE and TRAP dyestuff, and observed the osteoclasts under light and scanning electron microscope. There were large quantity of various forms of overlapping and huge osteoclasts with many nuclei and silk-like protuberances on the resorbing surface of deciduous teeth. The multinucleated osteoclasts align on the surface of coarse dentin. On the resorbing surface of human deciduous teeth there are large amount of osteoclasts which can be used as a source of studying human osteoclast.

Investigation of 16% carbamide-peroxide on the structure and properties and effect return enamel staining teeth whitening after their

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Matvijenko Vladimir

2015-01-01

Full Text Available The most tooth whitening is a procedure that removes stains and various discolorations of tooth surface. Discoloration of teeth may be endogenous and exogenous nature. The aim of this study was to investigate the impact of bleaching combined with daily use of drinks that cause tooth discoloration. Evaluated the changes in surface structure of enamel, and changes in hardness after bleaching. Were 20 extracted teeth. The teeth are marked with longitudinal lines halves (medial vestibular and distal surfaces. Tretitana mesial half of the 16% carbamide peroxide, a distal was left as control. NDT device HL-400DL, duroskopskom method of enamel hardness was measured before treatment, after treatment and after remineralization. Olympus inverted microscope GX41 enamel structures were observed in the treated and control half of the tooth. After bleaching there is a difference compared to the untreated surface, that surface is bleached a few shades lighter, but after the use of coffee and soft drinks teeth back to the original dark color. Enamel microhardness after the treatment is somewhat small but not significant. With a magnification of 2000x and see the structural changes in enamel. Tooth whitening, but that the remineralization and the abstinence from prebojenih beverages and tobacco.

Bilateral Supernumerary Teeth in Deciduous Dentition-A Rarity

OpenAIRE

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

2014-01-01

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 and more often seen in males. A supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent centr...

Polycarbonate crowns for primary teeth revisited: Restorative options, technique and case reports

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Karthik Venkataraghavan

2014-01-01

Full Text Available Esthetics by definition is the science of beauty - that particular detail of an animate or inanimate object that makes it appealing to the eye. In the modern, civilized, and cosmetically conscious world, well-contoured and well-aligned white teeth set the standard for beauty. Such teeth are not only considered attractive but are also indicative of nutritional health, self esteem, hygienic pride, and economic status. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. Even though researchers have claimed that certain restorations are better than the others, particularly owing to the issues mentioned above, the search for the ideal esthetic restoration for the primary teeth continues. This paper revisits and attempts to reintroduce the full coverage restoration, namely, polycarbonate crown, for use in primary anterior teeth.

Overeruption of teeth opposing removable partial dentures: a preliminary study.

Science.gov (United States)

Matsuda, Ken-Ichi; Miyashita, Yuji; Ikebe, Kazunori; Enoki, Kaori; Kurushima, Yuko; Mihara, Yusuke; Maeda, Yoshinobu

2014-01-01

One of the purposes of prosthodontic treatment is to prevent overeruption of opposing teeth, but there is currently minimal literature describing the efficacy of removable partial dentures (RPDs) in performing this function. This study investigated overeruption following RPD treatment. The study participants were 33 patients treated with RPDs, and overeruption was evaluated by comparing the surface computeraided design data of dental casts made at two different time points-before and after RPD treatment. Overeruption was observed in 38.1% of teeth opposed by the RPD, which was much less than the proportion of teeth that overerupted when not opposed by the RPD.

The roentgenographic study on the thickness of the lamina dura in normal teeth

Energy Technology Data Exchange (ETDEWEB)

Park, Chang Sik; Ahn, Hyung Kyu [Department of Dental Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1976-11-15

The study was performed to investigate the thickness of laminadura of the human teeth in normal condition, which obtained from the intraoral roentgenograms of the 1200 cases taken by bisecting technique. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. With advancing age in both sexes, the laminadura tends to become thinner as following. Average thickness of the whole cases. 2. In general, the alveolar crest is thickest among the root surfaces, apex, midroot followed, and the average thickness of the posterior teeth is thicker than that of the anterior teeth. 3. The mean value of the whole maxillary teeth is larger than the one of the whole mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.019 mm, which is not a significant differences.

Evaluation of Survival Time of Tooth Color Dental Materials in Primary Anterior Teeth

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Behjat-Al-Molook Ajami

2013-01-01

Full Text Available Introduction: In restorative dentistry, selecting the proper material is an important factor for clinical success. The objective of this study was clinical evaluation of survival time of three tooth color materials in primary anterior teeth. Methods: In this interventional clinical trial study, 94 deciduous anterior teeth (36 teeth in boys, 58 teeth in girls belonging to 3-5 year old children in Pediatric Department of Mashhad Faculty of Dentistry, Iran were selected. Selective dental materials included compoglass, glass-ionomer Fuji II LC, and composite resin. The data were analyzed with Kaplan–Meyer and Log rank test. Results: compoglass had the highest survival time in comparison with composite and glass-ionomer. Nine months retention rate for teeth restored with compoglass, composite resin and glass-ionomer were estimated: 95%, 21%, and 12.5%, respectively. Conclusion: Compoglass can be a suitable material for anterior primary teeth restoration

Evaluation of Survival Time of Tooth Color Dental Materials in Primary Anterior Teeth

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Taraneh Movahhed

2012-09-01

Full Text Available Introduction: In restorative dentistry, selecting the proper material is an important factor for clinical success. The objective of this study was clinical evaluation of survival time of three tooth color materials in primary anterior teeth. Methods: In this interventional clinical trial study, 94 deciduous anterior teeth (36 teeth in boys, 58 teeth in girls belonging to 3-5 year old children in Pediatric Department of Mashhad Faculty of Dentistry, Iran were selected. Selective dental materials included compoglass, glass-ionomer Fuji II LC, and composite resin. The data were analyzed with Kaplan–Meyer and Log rank test. Results: compoglass had the highest survival time in comparison with composite and glass-ionomer. Nine months retention rate for teeth restored with compoglass, composite resin and glass-ionomer were estimated: 95%, 21%, and 12.5%, respectively. Conclusion: Compoglass can be a suitable material for anterior primary teeth restoration.

Late Middle Pleistocene hominin teeth from Panxian Dadong, South China.

Science.gov (United States)

Liu, Wu; Schepartz, Lynne A; Xing, Song; Miller-Antonio, Sari; Wu, Xiujie; Trinkaus, Erik; Martinón-Torres, María

2013-05-01

The hominin teeth and evidence of hominin activities recovered from 1991 to 2005 at the Panxian Dadong site in South China are dated to the late Middle Pleistocene (MIS 8-6 or ca. 130-300 ka), a period for which very little is known about the morphology of Asian populations. The present study provides the first detailed morphometric description and comparisons of four hominin teeth (I(1), C1, P(3) and P3) from this site. Our study shows that the Panxian Dadong teeth combine archaic and derived features that align them with Middle and Upper Pleistocene fossils from East and West Asia and Europe. These teeth do not display any typical Neanderthal features and they are generally more derived than other contemporaneous populations from Asia and Africa. However, the derived traits are not diagnostic enough to specifically link the Panxian Dadong teeth to Homo sapiens, a common problem when analyzing the Middle Pleistocene dental record from Africa and Asia. These findings are contextualized in the discussion of the evolutionary course of Asian Middle Pleistocene hominins, and they highlight the necessity of incorporating the Asian fossil record in the still open debate about the origin of H. sapiens. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of tumor therapeutic irradiation on the mechanical properties of teeth tissue

Energy Technology Data Exchange (ETDEWEB)

Fraenzel, W. [Dept. of Physics, Martin Luther Univ. Halle (Germany); Gerlach, R. [Univ. Clinic and Policlinic for Radiation Therapy, Martin Luther Univ. Halle (Germany); Hein, H.J. [Univ. Clinic and Policlinic for Orthopaedics and Physical Medicine, Martin Luther Univ. Halle (Germany); Schaller, H.G. [Dept. of Operative Dentistry and Periodontology, Martin Luther Univ. Halle (Germany)

2006-07-01

Tumor irradiation of the head-neck area is accompanied by the development of a so-called radiation caries in the treated patients. In spite of conservative therapeutic measures, the process results in tooth destruction. The present study investigated the effects of irradiation on the demineralization and remineralization of the dental tissue. For this purpose, retained third molars were prepared and assigned either to a test group, which was exposed to fractional irradiation up to 60 Gy, or to a non-irradiated control group. Irradiated and non-irradiated teeth were then demineralized using acidic hydroxyl-cellulose gel; afterwards the teeth were remineralized using either Bifluorid12 {sup registered} or elmex gelee {sup registered}. The nanoindentation technique was used to measure the mechanical properties, hardness and elasticity, of the teeth in each of the conditions. The values were compared to the non-irradiated control group. Irradiation decreased dramatically the mechanical parameters of enamel and dentine. In non-irradiated teeth, demineralization had nearly the same effects of irradiation on the mechanical properties. In irradiated teeth, the effects of demineralization were negligible in comparison to non-irradiated teeth. Remineralization with Bifluorid12 {sup registered} or elmex gelee {sup registered} led to a partial improvement of the mechanical properties of the teeth. The enamel was more positively affected, by remineralization than the dentine. (orig.)

Diabetes or hypertension as risk indicators for missing teeth ...

African Journals Online (AJOL)

A negative binomial regression (NBR) model was generated. Results: Mean age was 50.7 ± 16.2 and 50.0% were women. Mean number of missing teeth was 4.98 ± 4.17. In the multivariate NBR model, we observed that individuals with T2DM had higher risk of more missing teeth (incidence rate ratios [IRRs] = 3.13; 95% ...

Observance to the teeth casts of fluorination after head and neck irradiation

International Nuclear Information System (INIS)

Albarghach, N.; Righini, C.; Thariat, J.

2009-01-01

The application of teeth casts with fluorinated gel is omitted in practice after six months for most of patients. The reasons can be an inadequate information on the application time of casts, mucitis pain during excessive application of fluorinated gel during irradiation creating then, apprehension of fluorinated gels. A questionnaire of observance during the consultation can be an education tool. repeated for the same patients at the next follow up consultation and compared it could allow to measure the impact of awareness measures during the follow up. (N.C.)

Prevalence rate of supernumerary teeth among non-syndromic South Indian population: An analysis

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M Nazargi Mahabob

2012-01-01

Full Text Available Aim: Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stage. The main objective of the study was to determine the prevalence rate of supernumerary teeth in the patients who reported to the Department of Oral Medicine and Radiology and to study the associated clinical complications. Materials and Methods: A longitudinal observational study was conducted of 2216 patients for a period of 4 months with the documentation of demographic data, the presence of supernumerary teeth, their location, and associated complications such as mechanical trauma, dental caries, and associated pathology. Results: The study recorded 27 supernumerary teeth from the examined 2216 patients. This yields a prevalence of 1.2%, with greater frequency in males which was 1.49% and in females the frequency was 0.85%. The greatest proportion of supernumerary teeth was found in the maxillary anterior region (77.8%. Out of this, 85.7% were classified as mesiodens based on their location. The displacement of adjacent teeth was the most common finding, followed by dental caries. Conclusion: The prevalence of supernumerary teeth in this study was 1.2% which is in agreement with that reported in similar studies and the maxillary mesiodens was the most common location. Displacement of adjacent teeth was the most common finding.

Incidence of two canals in extracted mandibular incisors teeth of Saudi Arabian samples

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Khalid S Al-Fouzan

2012-01-01

Full Text Available Aim: The purpose of this in vitro study is to provide clinical data on the presence of the second canal in mandibular incisor teeth of Saudi Arabian Samples. Materials and Methods: Eighty extracted human mandibular incisors were collected from Saudi patients. The teeth were accessed by small round bur then placed in 5.25% sodium hypochlorite for 24 hours to dissolve the organic debris. Indian ink was injected inside the root canal systems under negative pressure. The teeth were decalcified in 5% nitric acid for three days then dehydrated in different concentrations of ethyl alcohol. Following the decalcification process, the teeth were cleared in methyl salicylate and evaluated according to Vertucci′s classification. Result: Fifty six of both mandibular central and lateral incisor teeth (70% had type I canal configuration (one main canal and one main apical foramen, while the remaining 30% of the sample (24 teeth had a type III canal configuration (two separate canals and merged into one canal before exiting the tooth through single apical foramen. Conclusion : The incidence of two canals in mandibular incisor teeth is about one third of the examined Saudi Arabian samples with no difference between the centrals and laterals. The clinician should deal with these teeth as if they have two canals unless it is proved otherwise.

Three-dimensional cone-beam computed tomography: A new approach to the diagnosis and treatment planning of impacted mandibular third molars

International Nuclear Information System (INIS)

Kanazirska, P.; Yordanov, G.; Angelova, I.; Kanazirski, N.

2017-01-01

Cone Beam Computed Tomography (CBCT) is a relatively new method in dental practice which raises a more precise diagnosis and correct treatment plan. The image of the impacted teeth and surrounding structures with CBCT are with better quality and informativity than the conventional imaging-diagnostic methods . The use of CBCT to determine the ratio of the impacted teeth to the mandibular canal is necessary for the prevention of complications associated with iatrogenic trauma to the vascular- nerve bundle. The aim of this study was to determine the anatomic relationship between the roots of impacted third molars and mandibular canal using CBCT imaging. The studied patients with impacted third molars of the mandible are 127, aged 17 through 60.They were examined with Cone-beam Computed Tomography (CBCT). From the 195 impacted third molar with the - higher frequency are those in which the channel is below their roots-107 teeth (54.9%). The second frequency are the teeth where the channel is located lingually-57 (29.2%). Follow the teeth, in which the channel has a buccal location-25 (12.8%). With the lowest frequency are cases in which the mandibular canal is between the roots of impacted teeth-6 teeth (3.1%).At 132 teeth (67.7%) mandibular canal is at a distance of 1 mm. At 63 teeth (32.3%) the channel is at a distance of over 1 mm. The high resolution cuts in different planes and three-dimensional reconstructions made substantially as set forth preferred for different specialists in dentistry. Precise measurements of the bone around the mandibular canal prevent damage to neurovascular bundle. This makes the method preferred for planning appropriate treatment. Key words: Cone Beam Computed Tomography. Impacted Third Molars. Mandibular Canal [bg

Cultural significance of primary teeth for caregivers in Northeast Brazil.

Science.gov (United States)

Nations, Marilyn K; Calvasina, Paola Gondim; Martin, Michele N; Dias, Hilma Fontenele

2008-04-01

This anthropological study critically evaluates Brazilian caregivers' symbolic production and significance of their malnourished offspring's primary teeth, as well as their own, and describes popular dental practices. From January to June 2004, ethnographic interviews of 27 poor, low-literacy mothers were conducted at a public Malnutrition Treatment Center in Fortaleza, Ceará State. Participant observation of clinical pathways and home environments supplemented the data. Content analysis was performed. Results confirm that primary teeth are imbued with cultural significance in Northeast Brazil. Mothers examine mouths, perceive signs of decay, associate primary with permanent tooth healthiness, identify ethnodental illnesses, seek assistance, and perform rituals with exfoliated teeth. The mother's motivation to care for primary teeth is sparked by her memories of past toothache and attempts to avoid stigma and discrimination. Social determinants, not mothers' beliefs or behaviors, are the most critical obstacles to effective dental care. Legitimizing lay knowledge and empowering caregivers and children can improve oral health in Northeast Brazil.

Revitalization of open apex teeth with apical periodontitis using a collagen-hydroxyapatite scaffold.

Science.gov (United States)

Nevins, Alan J; Cymerman, Jerome J

2015-06-01

An enhanced revision of the revitalization endodontic technique for immature teeth with apical periodontitis has been described. It includes the addition of collagen-hydroxyapatite scaffold to the currently practiced revascularization technique. Four cases treated in series are presented in this report, 1 case involving 2 teeth. Periapical diagnoses of immature teeth included "asymptomatic apical periodontitis," "symptomatic apical periodontitis," and "acute apical abscess." Additionally, 1 fully developed tooth that had undergone root canal treatment that failed had a periapical diagnosis of acute apical abscess. An established revascularization protocol was used for all teeth. In addition to stimulating blood clots, all teeth were filled with collagen-hydroxyapatite scaffolds. Periapical radiolucencies healed in all teeth, and diffuse radiopacity developed within the coronal portions of canal spaces. Root development with root lengthening occurred in the immature nonvital maxillary premolar that had not undergone prior treatment. The technique of adding a collagen-hydroxyapatite scaffold to the existing revitalization protocol has been described in which substantial hard tissue repair has occurred. This may leave teeth more fully developed and less likely to fracture. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Permanent magnet machines with air gap windings and integrated teeth windings

Energy Technology Data Exchange (ETDEWEB)

Alatalo, M [Chalmers Univ. of Technology, Goeteborg (Sweden). School of Electrical and Computer Engineering

1996-06-01

The Thesis deals with axial and radial flux permanent magnet machines with air gap windings and an integrated teeth winding. The aim is to develop a machine that produces a high torque per unit volume with as low losses as possible. The hypothesis is that an advanced three-phase winding, magnetized by a permanent magnet rotor should be better than other machine topologies. The finite element method is used to find favourable dimensions of the slotless winding, the integrated teeth winding and the permanent magnet rotor. Three machines were built and tested in order to verify calculations. It can be concluded that the analysis method shows good agreement with the calculated and the measured values of induced voltage and torque. The experiments showed that the slotless machine with NdFeB-magnets performs approximately like the slotted machine. A theoretical comparison of axial flux topology to radial flux topology showed that the torque production of the inner rotor radial flux machine is superior to that of the axial flux machine. An integrated teeth winding based on iron powder teeth glued to the winding was studied. The force density of a pole with integrated teeth is around three times the force density of a slotless pole. A direct drive wind power generator of 6.4 kW with integrated teeth can have the same power losses and magnet weight as a transversal flux machine. Compared to a standard induction machine the integrated teeth machine had approximately 2.5 times the power capacity of the induction machine with the same power losses and outer volume. 39 refs

Caries, Periodontal Disease, Supernumerary Teeth and Other Dental Disorders in Swedish Wild Boar (Sus scrofa).

Science.gov (United States)

Malmsten, A; Dalin, A-M; Pettersson, A

2015-07-01

Between January and December 2013, the dental and periodontal health of 99 Swedish wild boars (Sus scrofa) was investigated. Sampling occurred in conjunction with routine hunting at six large estates in the southern and middle parts of Sweden. All six of the estates use supplemental feeding. The weight of the animals, their sex and their dates of death were noted. Age was estimated using tooth eruption and tooth replacement patterns. The oral cavity was inspected and abnormalities were recorded on a dental chart modified for wild boars. The findings included supernumerary teeth, absence of teeth, mild class II malocclusion, severe tooth wear, periodontitis, calculus, caries, tooth fractures and the presence of enamel defects. Swedish wild boars suffer from different dental lesions and the impact of supplemental feeding on dental and periodontal health is still to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dental anomalies associated with buccally- and palatally-impacted maxillary canines.

Science.gov (United States)

Sajnani, Anand K; King, Nigel M

2014-08-01

The aim of the present study was to determine the association of both buccally- and palatally-impacted canines with other dental anomalies. This retrospective study was conducted on a population of 533 southern Chinese children and adolescents who had impacted maxillary canines that had been treated in the Paediatric Dentistry and Orthodontics Clinic, Prince Philip Dental Hospital, The University of Hong Kong, Hong Kong. Descriptions of the impacted canine and other associated anomalies were obtained from the case notes and radiographs. Clinical photographs and study casts were used, where available. A total of 253 (47.5%) patients with impacted maxillary canines were diagnosed with other dental anomalies. Microdontia was the most frequently-occurring anomaly reported in these patients, with the maxillary lateral incisor the most commonly affected tooth. Other odontogenic anomalies that were associated with both buccally- and palatally-impacted canines included hypodontia, supernumerary teeth, transposition of other teeth, enamel hypoplasia, other impacted teeth, and dens invaginatus. Both buccally- and palatally-impacted canines were found to be associated with other odontogenic anomalies. © 2013 Wiley Publishing Asia Pty Ltd.

HSPG-deficient zebrafish uncovers dental aspect of multiple osteochondromas.

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Malgorzata I Wiweger

Full Text Available Multiple Osteochondromas (MO; previously known as multiple hereditary exostosis is an autosomal dominant genetic condition that is characterized by the formation of cartilaginous bone tumours (osteochondromas at multiple sites in the skeleton, secondary bursa formation and impingement of nerves, tendons and vessels, bone curving, and short stature. MO is also known to be associated with arthritis, general pain, scarring and occasional malignant transformation of osteochondroma into secondary peripheral chondrosarcoma. MO patients present additional complains but the relevance of those in relation to the syndromal background needs validation. Mutations in two enzymes that are required during heparan sulphate synthesis (EXT1 or EXT2 are known to cause MO. Previously, we have used zebrafish which harbour mutations in ext2 as a model for MO and shown that ext2⁻/⁻ fish have skeletal defects that resemble those seen in osteochondromas. Here we analyse dental defects present in ext2⁻/⁻ fish. Histological analysis reveals that ext2⁻/⁻ fish have very severe defects associated with the formation and the morphology of teeth. At 5 days post fertilization 100% of ext2⁻/⁻ fish have a single tooth at the end of the 5(th pharyngeal arch, whereas wild-type fish develop three teeth, located in the middle of the pharyngeal arch. ext2⁻/⁻ teeth have abnormal morphology (they were shorter and thicker than in the WT and patchy ossification at the tooth base. Deformities such as split crowns and enamel lesions were found in 20% of ext2⁺/⁻ adults. The tooth morphology in ext2⁻/⁻ was partially rescued by FGF8 administered locally (bead implants. Our findings from zebrafish model were validated in a dental survey that was conducted with assistance of the MHE Research Foundation. The presence of the malformed and/or displaced teeth with abnormal enamel was declared by half of the respondents indicating that MO might indeed be also associated

Teeth grinding, oral motor performance and maximal bite force in cerebral palsy children.

Science.gov (United States)

Botti Rodrigues Santos, Maria Teresa; Duarte Ferreira, Maria Cristina; de Oliveira Guaré, Renata; Guimarães, Antonio Sergio; Lira Ortega, Adriana

2015-01-01

Identify whether the degree of oral motor performance is related to the presence of teeth grinding and maximal bite force values in children with spastic cerebral palsy. Ninety-five spastic cerebral palsy children with and without teeth grinding, according to caregivers' reports, were submitted to a comprehensive oral motor performance evaluation during the feeding process using the Oral Motor Assessment Scale. Maximal bite force was measured using an electronic gnathodynamometer. The teeth grinding group (n = 42) was younger, used anticonvulsant drugs, and was more frequently classified within the subfunctional oral motor performance category. Teeth grinding subfunctional spastic cerebral palsy children presented lower values of maximal bite force. The functional groups showing the presence or absence of teeth grinding presented higher values of maximal bite force compared with the subfunctional groups. In spastic cerebral palsy children, teeth grinding is associated with the worse oral motor performance. © 2015 Special Care Dentistry Association and Wiley Periodicals, Inc.

Impact of the 'non-destructive' multiple-readout on the Lorentzian noise

International Nuclear Information System (INIS)

Guazzoni, C.; Gatti, E.; Geraci, A.

2006-01-01

In this paper, we discuss the effect of 'non-destructive' multiple-readout on the Lorentzian noise. To our knowledge, it is the first time that such interaction is investigated. We have studied the peculiarities of the shape of the optimum weighting function for the multiple-readout technique in the presence of Lorentzian noise and other noise sources. The impact of the Lorentzian noise on the resolution achievable with the multiple-readout technique is analyzed in detail with respect to the interaction between the oscillation time and the characteristic time constant of the Lorentzian noise

The detailed evaluation of supernumerary teeth with the aid of cone beam computed tomography

International Nuclear Information System (INIS)

Tumen, E.C.; Yavuz, I.; Atakul, F.; Tumen, D.S.; Hamamci, N.; Berber, G.; Uysal, E.

2010-01-01

The aim of this paper is to demonstrate the application of a recently developed three-dimensional imaging system, cone beam computed tomography, in the detailed evaluation of supernumerary teeth. Two-hundred and twenty three patients with supernumerary teeth (68 females and 155 males) were included in this study. Patients ranged in age from 12 to 25 years. Supernumerary teeth were detected by clinical examination and traditional radiographies. Moreover, careful investigation for more details was made with the cone beam computed tomography. Supernumerary teeth which were detected with the examinations of the cone beam computed tomography images were classified according to the number, location, shape and eruption rate. The prevalence of supernumerary teeth was determined to be 1.45% of the study population. Males were affected more than females in a ratio of 2.3:1. Supernumerary teeth were most frequently located in 86.2% of the cases in the maxilla; 10.1% in the mandible and 3.7% both in the maxilla and mandible. Supernumerary teeth were most commonly conical in shape (68.8%). One supernumerary tooth was present in 67.7% of the patients, 30.9% had two, and 1.4% had three supernumeraries. Definite and early diagnosis of the supernumerary teeth is very important. Detailed examinations and evaluations of these teeth with three-dimensional images is very beneficial in terms of treatment planning and preventing complications which may occur.

Fracture modes in human teeth.

Science.gov (United States)

Lee, J J-W; Kwon, J-Y; Chai, H; Lucas, P W; Thompson, V P; Lawn, B R

2009-03-01

The structural integrity of teeth under stress is vital to functional longevity. We tested the hypothesis that this integrity is limited by fracture of the enamel. Experiments were conducted on molar teeth, with a metal rod loaded onto individual cusps. Fracture during testing was tracked with a video camera. Two longitudinal modes of cracking were observed: median cracking from the contact zone, and margin cracking along side walls. Median cracks initiated from plastic damage at the contact site, at first growing slowly and then accelerating to the tooth margin. Margin cracks appeared to originate from the cemento-enamel junction, and traversed the tooth wall adjacent to the loaded cusp from the gingival to the occlusal surface. All cracks remained confined within the enamel shell up to about 550 N. At higher loads, additional crack modes--such as enamel chipping and delamination--began to manifest themselves, leading to more comprehensive failure of the tooth structure.

Hen's teeth with enamel cap: from dream to impossibility

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Girondot Marc

2008-09-01

Full Text Available Abstract Background The ability to form teeth was lost in an ancestor of all modern birds, approximately 100-80 million years ago. However, experiments in chicken have revealed that the oral epithelium can respond to inductive signals from mouse mesenchyme, leading to reactivation of the odontogenic pathway. Recently, tooth germs similar to crocodile rudimentary teeth were found in a chicken mutant. These "chicken teeth" did not develop further, but the question remains whether functional teeth with enamel cap would have been obtained if the experiments had been carried out over a longer time period or if the chicken mutants had survived. The next odontogenetic step would have been tooth differentiation, involving deposition of dental proteins. Results Using bioinformatics, we assessed the fate of the four dental proteins thought to be specific to enamel (amelogenin, AMEL; ameloblastin, AMBN; enamelin, ENAM and to dentin (dentin sialophosphoprotein, DSPP in the chicken genome. Conservation of gene synteny in amniotes allowed definition of target DNA regions in which we searched for sequence similarity. We found the full-length chicken AMEL and the only N-terminal region of DSPP, and both are invalidated genes. AMBN and ENAM disappeared after chromosomal rearrangements occurred in the candidate region in a bird ancestor. Conclusion These findings not only imply that functional teeth with enamel covering, as present in ancestral Aves, will never be obtained in birds, but they also indicate that these four protein genes were dental specific, at least in the last toothed ancestor of modern birds, a specificity which has been questioned in recent years.

Preformed crowns for decayed primary molar teeth.

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Innes, Nicola P T; Ricketts, David; Chong, Lee Yee; Keightley, Alexander J; Lamont, Thomas; Santamaria, Ruth M

2015-12-31

Crowns for primary molars are preformed and come in a variety of sizes and materials to be placed over decayed or developmentally defective teeth. They can be made completely of stainless steel (know as 'preformed metal crowns' or PMCs), or to give better aesthetics, may be made of stainless steel with a white veneer cover or made wholly of a white ceramic material. In most cases, teeth are trimmed for the crowns to be fitted conventionally using a local anaesthetic. However, in the case of the Hall Technique, PMCs are pushed over the tooth with no local anaesthetic, carious tissue removal or tooth preparation. Crowns are recommended for restoring primary molar teeth that have had a pulp treatment, are very decayed or are badly broken down. However, few dental practitioners use them in clinical practice. This review updates the original review published in 2007. Primary objectiveTo evaluate the clinical effectiveness and safety of all types of preformed crowns for restoring primary teeth compared with conventional filling materials (such as amalgam, composite, glass ionomer, resin modified glass ionomer and compomers), other types of crowns or methods of crown placement, non-restorative caries treatment or no treatment. Secondary objectiveTo explore whether the extent of decay has an effect on the clinical outcome of primary teeth restored with all types of preformed crowns compared with those restored with conventional filling materials. We searched the following electronic databases: Cochrane Oral Health Group Trials Register (to 21 January 2015), Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library, 2014, Issue 12), MEDLINE via Ovid (1946 to 21 January 2015) and EMBASE via Ovid (1980 to 21 January 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials and Open Grey for grey literature (to

Pulpal status of human primary teeth with physiological root resorption.

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Monteiro, Joana; Day, Peter; Duggal, Monty; Morgan, Claire; Rodd, Helen

2009-01-01

The overall aim of this study was to determine whether any changes occur in the pulpal structure of human primary teeth in association with physiological root resorption. The experimental material comprised 64 sound primary molars, obtained from children requiring routine dental extractions under general anaesthesia. Pulp sections were processed for indirect immunofluorescence using combinations of: (i) protein gene product 9.5 (a general neuronal marker); (ii) leucocyte common antigen CD45 (a general immune cell marker); and (iii) Ulex europaeus I lectin (a marker of vascular endothelium). Image analysis was then used to determine the percentage area of staining for each label within both the pulp horn and mid-coronal region. Following measurement of the greatest degree of root resorption in each sample, teeth were subdivided into three groups: those with physiological resorption involving less than one-third, one-third to two-thirds, and more than two-thirds of their root length. Wide variation was evident between different tooth samples with some resorbed teeth showing marked changes in pulpal histology. Decreased innervation density, increased immune cell accumulation, and increased vascularity were evident in some teeth with advanced root resorption. Analysis of pooled data, however, did not reveal any significant differences in mean percentage area of staining for any of these variables according to the three root resorption subgroups (P > 0.05, analysis of variance on transformed data). This investigation has revealed some changes in pulpal status of human primary teeth with physiological root resorption. These were not, however, as profound as one may have anticipated. It is therefore speculated that teeth could retain the potential for sensation, healing, and repair until advanced stages of root resorption.

Mucoid impaction presenting as multiple pulmonary nodules in cystic fibrosis

International Nuclear Information System (INIS)

Carpenter, L.D.; Lambie, N.K.; Wilsher, M.L.

1996-01-01

Mucoid impaction has been described as a complication of asthma and more commonly in patients with allergic bronchopulmonary aspergillosis. In such cases, the impacted pools of mucus may present as discrete nodules on chest X-ray and hence simulate the appearance of metastatic malignancy. A case of mucoid impaction presenting as multiple pulmonary nodules in a patient with cystic fibrosis is described. The chest X-ray showed hyperinfiltration and scattered changes consistent with bronchiectasis. Computed tomography scan confirmed these and additional intra-pulmonary nodular densities. This report illustrates that mucus impaction as a cause of pulmonary nodules should be considered in any patient with chronic lung disease characterised by excess mucus production. 6 refs., 3 figs

Colour stability of denture teeth submitted to different cleaning protocols and accelerated artificial aging.

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Freire, T S; Aguilar, F G; Garcia, L da Fonseca Roberti; Pires-de-Souza, F de Carvalho Panzeri

2014-03-01

Acrylic resin is widely used for artificial teeth manufacturing due to several important characteristics; however, this material do not present acceptable colour stability over the course of time. This study evaluated the effect of different cleaning protocols and accelerated artificial aging on colour stability of denture teeth made of acrylic resin. Sixty denture teeth in dark and light shades were used, and separated according to the treatment to which they were submitted. Results demonstrated that colour stability of artificial teeth is influenced by the cleaning solution and artificial aging, being dark teeth more susceptible to colour alteration than lighter ones.

Influences of age and maxillary anterior teeth status on patient's satisfaction with dental appearance and tooth colour.

Science.gov (United States)

Lajnert, Vlatka; Pavičić, Daniela K; Gržić, Renata; Kovač, Zoran; Pahor, Dana; Kuis, Davor; Simonić-Kocijan, Sunčana; Antonić, Robert; Bakarčić, Danko

2012-06-01

To study the impact of age, gender, tooth colour and maxillary anterior teeth status on patient's satisfaction with their dental appearance. A total of 259 Caucasian subjects participated in the study (119 men, mean age 56 years; 140 women, mean age 61 years) divided into three age groups (young colour using a scale with three categories: completely dissatisfied, moderately dissatisfied and completely satisfied. Almost half of the participants were completely satisfied with their dental appearance and tooth colour. Half of the 'young' and 'middle-aged' participants with natural maxillary anterior teeth were completely satisfied and half of the 'old' participants were moderately satisfied with their dental appearance and tooth colour. The majority of participants with composite restorations (45-51%) were moderately satisfied with their dental appearance, one-third of 'young' and 'middle-aged' participants were moderately satisfied or dissatisfied with their tooth colour and more than 70% of older participants were dissatisfied with their tooth colour (p > 0.05). Satisfaction with the appearance of the maxillary anterior teeth differed both between individuals of different age and different dental status. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Comparative evaluation of shear bond strength of two self-etching adhesives (sixth and seventh generation on dentin of primary and permanent teeth: An in vitro study

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Yaseen S

2009-03-01

Full Text Available Aim: The present study was undertaken to compare and evaluate shear bond strength of two self-etching adhesives (sixth and seventh generation on dentin of primary and permanent teeth. Materials and Methods: Flat dentin surface of 64 human anterior teeth (32 primary and 32 permanent divided into four groups of 16 each. Groups A and C were treated with Contax (sixth generation, while groups B and D were treated with Clearfil S3 (seventh generation. A teflon mold was used to build the composite (Filtek Z-350 cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. Data were statistically analyzed using one-way ANOVA for multiple group comparison, followed by student′s unpaired ′t′ test for group-wise comparison. Results: There was no statistically significant difference in shear bond strength among the study groups except that primary teeth bonded with Contax exhibited significantly lesser shear bond strength than permanent teeth bonded with Clearfil S3. Conclusion: This study revealed that Clearfil S3 could be of greater advantage in pediatric dentistry than Contax because of its fewer steps and better shear bond strength in dentin of both primary and permanent teeth.

Quantitative and qualitative analysis of fluoride and multi elements of shark teeth by PIXE

International Nuclear Information System (INIS)

Sakurai, S.; Asakawa, R.; Hirota, F.; Sato, T.; Sera, K.; Itoh, J.

2008-01-01

Biomineralization has two types, biologically induced mineralization (BIM) and biologically controlled mineralization (BCM). Shark teeth is a typical representative of BCM. We have measured concentrations of fluorine and multi elements in shark teeth collected in the south of Japan. As a result, it was confirmed that the sample preparation method, which was established for the biological samples, is applicable to the shark teeth samples and the elemental concentration was obtained in good accuracy and reproducibility. Moreover, we clarified that the shark teeth is composed of Fluorapatite by the combination with X-ray Diffraction. Fluorine concentration is found to be 5500 μg/g in the shark teeth. We have 100 samples of Shark teeth and are planning on reporting the findings of a study with larger samples in the near future. (author)

Procedure for the automatic mesh generation of innovative gear teeth

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Radicella Andrea Chiaramonte

2016-01-01

Full Text Available After having described gear wheels with teeth having the two sides constituted by different involutes and their importance in engineering applications, we stress the need for an efficient procedure for the automatic mesh generation of innovative gear teeth. First, we describe the procedure for the subdivision of the tooth profile in the various possible cases, then we show the method for creating the subdivision mesh, defined by two series of curves called meridians and parallels. Finally, we describe how the above procedure for automatic mesh generation is able to solve specific cases that may arise when dealing with teeth having the two sides constituted by different involutes.

Root resorption of endodontically treated teeth following orthodontic treatment: a meta-analysis.

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Ioannidou-Marathiotou, Ioulia; Zafeiriadis, Anastasios A; Papadopoulos, Moschos A

2013-09-01

The aim of this meta-analysis was to investigate the effect of orthodontic treatment on root resorption of endodontically treated teeth compared to vital teeth. A literature search was conducted in 18 electronic databases. Review articles and relevant articles were searched for cross-references. Two independent reviewers screened all articles according to predefined inclusion and exclusion criteria and extracted the corresponding data. The pooled estimate of mean difference of root resorption weighted by the fixed-effect model and the corresponding 95 % confidence intervals (CIs) were used to construct a forest plot by implementing the "RevMan 5.1" software. Quality and heterogeneity assessments as well as publication bias evaluation and sensitivity analyses were performed. Inter-reviewer agreement for data selection, data extraction and quality analysis was evaluated by Cohen's kappa. Six out of 1,942 original papers met the inclusion criteria. Four out of six studies were included in the quantitative analysis. Root resorption was less in endodontically treated teeth than in vital teeth (MD = -0.48 mm; 95 % CI = -0.81 to -0.14 mm). The funnel plot indicated no evidence of publication bias, while no data heterogeneity was present (I(2) = 0 %). However, the overall quality of the included studies was considered as "low." Following orthodontic treatment, endodontically treated teeth exhibit relatively less root resorption than teeth with vital pulps. Clinicians should consider orthodontic movement of endodontically treated teeth as a relatively safe clinical procedure.

Assessment of Periodontal Status of Surgically Exposed and Orthodontically Aligned Impacted Maxillary Canines

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Adina Coșarcă

2014-02-01

Full Text Available Aim: The aim of this study was to compare the periodontal status of impacted canines after 5 years following completion of the combined surgical and orthodontic treatment. Materials and methods: We examined 20 labially impacted canines and 20 palatally impacted canines at 5 years after the end of treatment. We assessed the periodontal status of these teeth. Results: Different outcomes were found regarding the probing depth and the amount of keratinized gingiva in the two mentioned groups of teeth. Conclusions: The assessed periodontal indices may signal the appearance of a periodontal disease around the teeth that were surgically and orthodontically treated

Prediction of canine and premolar size using the widths of various permanent teeth combinations: A cross-sectional study

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Kalasandhya Vanjari

2015-01-01

Full Text Available Aims: To suggest the best predictor/s for determining the mesio-distal widths (MDWs of canines (C and premolars (Ps, and propose regression equation/s for hitherto unreported population. Methods: Impressions of maxillary and mandibular arches were made for 201 children (100 boys and 101 girls; age range: 11–15 years who met the inclusion criteria and poured with dental stone. The maximum MDWs of all the permanent teeth were measured using digital vernier caliper. Thirty-three possible combinations (patterns of permanent maxillary and mandibular first molars, central and lateral incisors were framed and correlated with MDWs of C and Ps using Pearson correlation test. Results: There were significant correlations between the considered patterns and MDWs of C and Ps, with difference noted between girls (range of r: 0.34–0.66 and boys (range of r: 0.28–0.77. Simple linear and multiple regression equations for boys, girls, and combined sample were determined to predict MDW of C and Ps in both the arches. Conclusions: The accuracy of prediction improved considerably with the inclusion of as many teeth as possible in the regression equations. The newly proposed equations based on the erupted teeth may be considered clinically useful for space analysis in the considered population.

Esthetic Rehabilitation of Primary Anterior Teeth using Temporization Material: A Novel Approach

Science.gov (United States)

Pandit, IK; Gupta, Monika; Nagpal, Jyoti

2017-01-01

Pediatric dentists should always aim for esthetic and functional rehabilitation of decayed/traumatized primary teeth. The most common method for restoring such teeth involves the use of “strip crowns” with composites, while the recent trend is toward using other extracoronal restorations including preve-neered stainless steel crowns and zirconia crowns. All these restorative options have shown good success rates, but also have some limitations. This case series depicts novel clinical technique of using a temporization material for full-coronal restoration(s) in primary anterior teeth. This included the chair-side custom fabrication of full-coronal restoration using temporization material, which has resulted in good immediate esthetics and might be a cost-effective alternative for restoring primary anterior teeth in future. How to cite this article Gugnani N, Pandit IK, Gupta M, Nagpal J. Esthetic Rehabilitation of Primary Anterior Teeth using Temporization Material: A Novel Approach. Int J Clin Pediatr Dent 2017;10(1):111-114. PMID:28377667

Radiologic study of peridontal and periapical changes for the restorated teeth

International Nuclear Information System (INIS)

Ahn, Hyung Kyu

1978-01-01

The purpose of this study is to investigate the effect of dental restorations on the periodontal and periapical tissues. The author examined 620 cases of amalgam, 390 cases of fold inlay, 442 cases of crown and 644 cases of bridge through the standard intraoral films being appended in the charts that gad been kept at the Dept. of Oral Diagnosis in Seoul National University Hospital. This study obtained the following results; 1. The restorations of amalgam, gold inlay crown and bridge were found more frequently in female than in male. 2. The restorations of amalgam, gold inlay and crown were found more numerously in mandibular teeth than in maxillary teeth in both sexes. But in the case of crown, the fact is quite the reverse especially in anterior teeth. 3. On the contrary, tn the case of bridge, the restorations of bridge were much more distributed in the maxillary teeth than in the mandibular teeth. 4. Roentgenographic changes of periodontal tissues whose teeth were treated with any type of four restorations were periodontal space widening, lamina dura discontinuity and periapical lesion in the order described in both sexes. 5. On the occasion of between amalgam and gold inlay or between crown and bridge, the differences of periodontal changes were of no consequence. On the other hand, the differences of periodontal changes were apparent between the group of amalgam and gold inlay and the group of crown and bridge.

Autotransplantation of teeth in humans: a systematic review and meta-analysis.

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Almpani, Konstantinia; Papageorgiou, Spyridon N; Papadopoulos, Moschos A

2015-07-01

The aim of this investigation was to assess the currently available evidence concerning the complications and risk factors influencing the outcome of autotransplantation of teeth in humans. Electronic searches were conducted to identify randomized controlled and prospective clinical trials. Risk of bias within studies was assessed with the Downs and Black tool. Random-effects meta-analyses were conducted to pool the adverse event rates and relative risks with their 95% confidence intervals. Risk of bias across studies was assessed with the GRADE framework followed by sensitivity analyses. Thirty-eight studies were included in the analysis. Reported complications included the need for extraction, failure, hypermobility, pulp necrosis, pulp obliteration, and root resorption. Pooled complication event rates varied considerably, with small studies (factors was associated with both the primary outcome (extraction need) and secondary outcomes (failure, hypermobility, pulp necrosis, pulp obliteration, root resorption). The stage of root development seems to influence both the future survival, as well as the success of the transplanted teeth. Teeth with open apex were less likely to be extracted in comparison to teeth with closed apex (3 studies; 413 teeth; relative risk 0.3; 95% confidence interval 0.2-0.6). Due to the small number of the contributing studies, their methodological limitations, and the heterogeneous results reported, no firm conclusions can be drawn. Root development of the donor teeth has been established as one the most important factor related to the success of tooth autotransplantation.

[Congenital absence and loss of teeth in an orthodontic patient group].

Science.gov (United States)

Dechkunakorn, S; Chaiwat, J; Sawaengkit, P

1990-01-01

Panoramic radiographs of 1,160 orthodontic patients, 655 females and 505 males, 6-15 years of age were selected for study in congenital absence, loss of permanent teeth and premature loss of deciduous teeth. The result from this investigation showed congenital absence for 100 subjects (8.6%, not including third molars) and 185 subjects (16%, third molars included). The permanent upper lateral incisors are most frequently missing (22.4%, third molars excluded), followed by upper second premolar, 17.8%, lower second premolar, 15.1%, and then lower lateral incisor, 12.5%. The study also showed loss of permanent teeth of 105 subjects (9.1%). The lower first molars are most frequently lost (52.8%), followed by the upper first molar (18.2%). There is no statistical significance (alpha = 0.01) between females and males in both congenital absence and loss of permanent teeth. The premature loss of deciduous teeth was found in 467 subjects (40.3%). The most frequently loss happened to second deciduous molars, followed by first deciduous molars and then deciduous canines. There is more statistical significance (alpha = 0.01) in females than in males.

Association between anticonvulsant drugs and teeth-grinding in children and adolescents with cerebral palsy.

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Ortega, A O L; Dos Santos, M T B R; Mendes, F M; Ciamponi, A L

2014-09-01

The relation between teeth-grinding and the use of drugs acting on the central nervous system of cerebral palsy (CP) patients has not yet been described. The aim of this research was to evaluate the presence or absence of teeth-grinding (sleep and/or awake periods) in normal and in CP children and adolescents, as well as the association of teeth-grinding and use of anticonvulsant drugs. The sample consisted of 207 children and adolescents, divided into three groups: G1, individuals with CP who did not take anticonvulsant drugs; G2, individuals with CP administered medications on a regular basis; and CG, normal individuals. Logistic regression analyses were performed to evaluate the association of teeth-grinding with some variables. No significant statistical differences were observed regarding the presence or absence of teeth-grinding when G1 and G2 were compared. However, compared with the CG, a statistically significant difference was determined, with the CG showing fewer children presenting teeth-grinding (P grinding. CP children and adolescents show a greater and significant presence of grinding of the teeth compared with normal individuals. Subjects taking barbiturate drugs showed greater presence of teeth-grinding, than those who were taking medications from the other groups of anticonvulsant drugs. © 2014 John Wiley & Sons Ltd.

Approximal morphology as predictor of approximal caries in primary molar teeth

DEFF Research Database (Denmark)

Cortes, A; Martignon, S; Qvist, V

2018-01-01

consent was given, participated. Upper and lower molar teeth of one randomly selected side received a 2-day temporarily separation. Bitewing radiographs and silicone impressions of interproximal area (IPA) were obtained. One-year procedures were repeated in 52 children (84%). The morphology of the distal...... surfaces of the first molar teeth and the mesial surfaces on the second molar teeth (n=208) was scored from the occlusal aspect on images from the baseline resin models resulting in four IPA variants: concave-concave; concave-convex; convex-concave, and convex-convex. Approximal caries on the surface...

Allogeneic stem cells derived from human exfoliated deciduous teeth (SHED for the management of periapical lesions in permanent teeth: Two case reports of a novel biologic alternative treatment

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Madu Ghana Shyam Prasad

2017-06-01

Full Text Available Stem cells are the pluripotent cells that have the capacity to differentiate into other specialized cells. Recently, many experiments have been conducted to study the potentiality of stem cells in the tissue regeneration. We report two cases treated utilizing stem cells from human exfoliated deciduous teeth (SHED in the management of periapical lesions in permanent teeth. Two normal human deciduous teeth from children, 7‒8 years of age, were collected to isolate stem cells. Two patients, one with periapical pathology alone and the other with periapical lesion along with an open apex in young permanent teeth, were selected for the study. After initial debridement of the root canals, homing of SHED was carried out and the access cavity was sealed using glass-ionomer cement. Clinical examination after 7 days, 30 days, 90 days, 180 days and 365 days revealed no symptoms. Closure of open apex and periapical tissue healing were observed radiographically at one-month review and maintained until 365-day review. Positive response to electric pulp testing was recorded for the treated teeth from the 3- to 12-month follow-ups. The treated cases demonstrated complete resolution of periapical radiolucency in a span of 30 days, which was faster than the conventional methods. SHED could be considred effective in treating the periapical lesions and open apex in permanent teeth.

A Rare Case of Apical Root Resorption during Orthodontic Treatment of Patient with Multiple Aplasia.

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Agrawal, Chintan M; Mahida, Khyati; Agrawal, Charu C; Bothra, Jitendrakumar; Mashru, Ketan

2015-07-01

External apical root resorption is an adverse effect of orthodontic treatment. It reduces the length of root and breaks the integrity of teeth and dental arch. Orthodontics is the only dental specialty that clinically uses the inflammatory process to correct the mal-aligned teeth. Hence, it is necessary to know the risk factors of root resorption and do everything to reduce the rate of root resorption. Hence, all predisposing factors which are systemic as well as local should be considered before treatment begins. This case report describes the incidence of root resorption following orthodontic treatment and the teeth affected in the patient with multiple aplasia.

Holes in teeth - Dental caries in Neolithic and Early Bronze Age populations in Central Germany.

Science.gov (United States)

Nicklisch, Nicole; Ganslmeier, Robert; Siebert, Angelina; Friederich, Susanne; Meller, Harald; Alt, Kurt W

2016-01-01

This study provides diachronic insight into the epidemiology of carious defects in teeth of Neolithic and Early Bronze Age populations in Central Germany over a period of 4000 years. The data were retrieved from skeletal remains uncovered at 21 sites throughout the Middle Elbe-Saale region (MES), comprising a total of 494 individuals with preserved teeth. The data generated were examined for age- and sex-related differences in order to gain information about the dietary habits and socio-economic structures of the period with the goal of identifying potential diachronic changes. The results indicated that dietary habits changed over the course of the Neolithic period: the prevalence of caries significantly decreased between the Early and Late Neolithic. The adults from the Early Neolithic sample, particularly those from the LBK bore the highest rate of caries. This highlights the essential importance of cereals in the diet of the early farmers in the Middle Elbe-Saale region. As time went on, meat and dairy products became more and more important, which had a positive impact on dental health. The data also show sex-specific differences: women were more often affected by caries than men and female jaws also generally exhibited greater numbers of carious teeth than their male counterparts. Dental health is a reflection of both biological factors and of economic and sociocultural structures. Copyright © 2015 Elsevier GmbH. All rights reserved.

A new mathematical process for the calculation of average forms of teeth.

Science.gov (United States)

Mehl, A; Blanz, V; Hickel, R

2005-12-01

Qualitative visual inspections and linear metric measurements have been predominant methods for describing the morphology of teeth. No quantitative formulation exists for the description of dental features. The aim of this study was to determine and validate a mathematical process for calculation of the average form of first maxillary molars, including the general occlusal features. Stone replicas of 174 caries-free first maxillary molar crowns from young patients ranging from 6 to 9 years of age were measured 3-dimensionally with a laser scanning system at a resolution of approximately 100,000 points. Then, the average tooth was computed, which captured the common features of the molar's surface quantitatively. This new method adapts algorithms both from computer science and neuroscience to detect and associate the same features and same surface points (correspondences) between 1 reference tooth and all other teeth. In this study, the method was tested for 7 different reference teeth. The algorithm does not involve any prior knowledge about teeth and their features. Irrespective of the reference tooth used, the procedure yielded average teeth that showed nearly no differences (less than +/-30 microm). This approach provides a valid quantitative process for calculating 3-dimensional (3D) averages of occlusal surfaces of teeth even in the event of a high number of digitized surface points. Additionally, because this process detects and assigns point-wise feature correspondences between all library teeth, it may also serve as a basis for a more substantiated principal component analysis evaluating the main natural shape deviations from the 3D average.

Simple replantation protocol to avoid ankylosis in teeth intended for orthodontic treatment

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Yuli Nugraeni

2009-03-01

Full Text Available Background: Dento-alveolar trauma resulted from accidents involving the oral regions mostly affect the upper central incisors. Overjet that is beyond 5 mm and incompetent lip also contribute to increase the risk. Several literatures had already discussed different methods of replantation of avulsed teeth. However, it was not meant for further orthodontic treatment. Purpose: The objective of this review is to propose a simple replantation protocol of avulsed teeth which also prevent from ankylosis. Reviews: Protruded teeth usually need orthodontic treatment; therefore, an appropriate management should be done to avoid the development of ankylosis. Ankylosis of the periodontal ligament (PDL becomes a problem in orthodontic tooth movement in repositioned or replanted teeth. In addition, ankylosed teeth also more susceptible to root resorption. Actually, it was caused by the endodontic treatment. In particular, severely protruded or unoccluded teeth are hypofunctional, therefore have narrow PDL, thus it may facilitate to ankylosis development. Ideal management protocol such as the use of root canal sealer i.e. mineral trioxide aggregate (MTA; the using of Emdogain, and resilient wiring or semi-rigid fixation with brackets has become a solution in avulsed teeth arranged for orthodontic treatment. Nevertheless, the presence of oral surgeon, endodontist and orthodontist in the same time, and also ideal preparations after an accident was difficult to achieve. Conclusion: Considering that reducing the ongoing PDL inflammation with intracanal medicaments and maintaining the functional force during mastication is possible; it is concluded that this simple replantation protocol is likely.

Analysis of cracks generated in the spinning-mandrel teeth

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M. Haghshenas

2014-10-01

Full Text Available The spinning process, using a splined mandrel, is always prone to premature failure of the splined mandrels. Such a failure is thought to be related to the magnitude of the forming forces exerted on the mandrel by the forming rollers during the spinning process. In the present paper, the characteristic of corner cracks in the mandrel teeth (made of S7 tool steel of a spinning process has been investigated. The rotational speed of the mandrel is about 300 rpm during spinning process and the sheet metal (i.e. AISI 1020 is in contact with mandrel teeth to get the mandrel shape at the end of process. During this process, the mandrel teeth eventually break away. Fractography analyses using scanning electron microscopy (SEM clearly confirm “fatigue” as being the main reason for the failure.

Multidisciplinary approach on rehabilitation of primary teeth traumatism repercussion on the permanent successor: 6-year follow-up case report

Directory of Open Access Journals (Sweden)

Mello-Moura ACV

2009-06-01

Full Text Available Traumatic lesions in primary teeth are frequent in pediatric patients and can cause problems both to the deciduous tooth and permanent successor. The impact strength on deciduous tooth can reach the growing permanent tooth, affecting its morphology, structure and position, or even hampering its proper development. This report describes an aesthetic-functional rehabilitation process in an 8 year 10 month old boy during a multidisciplinary treatment held at the Clinical Center of Dental Trauma in Primary Teeth of the Pediatric Dentistry of Dental College of University of São Paulo, Brazil. The patient presented bilateral posterior cross bite and the permanent left upper central incisor with ectopic eruption and enamel hypoplasy, preceded by avulsion of element 61, occurred when the patient was 1.6 years old. After diagnosis and treatment planning, a quick expansion of jaws was recommended with Hass-type rapid expander and orthodontic leveling with fixed braces. Due to the ectopic eruption, the gingival contour had been altered and hypertrophia was found, compromising aesthetics and avoiding local hygienic procedures. Gingivoplasty was carried out with high-intensity Diode Laser, followed by aesthetic restoration with compound resin. It was concluded that after deciduous teeth traumatism it is important that the patient undergoes clinic and radiographic assistance until the permanent teeth erupt so that an adequate multidisciplinary treatment can be offered to the patient.

Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

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Adrian Lussi

Full Text Available This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA to pH 5.5, calcium (Ca, inorganic phosphate (Pi, and fluoride (F concentration, and degree of saturation ((pK -pIHAP, (pK -pIFAP, and (pK-pICaF2 of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers and surface reflection intensity (SRI at baseline (SH baseline and SRI baseline, after a total of 2 min (SH2 min and after 4 min (SH4 min and SRI4 min erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm. There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007, but no differences between the two types of teeth were observed after two challenges (SH4 min. After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

Analyses of the Erosive Effect of Dietary Substances and Medications on Deciduous Teeth.

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Lussi, Adrian; Carvalho, Thiago Saads

2015-01-01

This study aimed at analysing the erosive potential of 30 substances (drinks, candies, and medicaments) on deciduous enamel, and analyse the associated chemical factors with enamel dissolution. We analysed the initial pH, titratable acidity (TA) to pH 5.5, calcium (Ca), inorganic phosphate (Pi), and fluoride (F) concentration, and degree of saturation ((pK -pI)HAP, (pK -pI)FAP, and (pK-pI)CaF2) of all substances. Then, we randomly distributed 300 specimens of human deciduous enamel into 30 groups (n = 10 for each of the substances tested. We also prepared 20 specimens of permanent enamel for the sake of comparison between the two types of teeth, and we tested them in mineral water and Coca-Cola®. In all specimens, we measured surface hardness (VHN: Vickers hardness numbers) and surface reflection intensity (SRI) at baseline (SH baseline and SRI baseline), after a total of 2 min (SH2 min) and after 4 min (SH4 min and SRI4 min) erosive challenges (60 ml of substance for 6 enamel samples; 30°C, under constant agitation at 95 rpm). There was no significant difference in SH baseline between deciduous and permanent enamel. Comparing both teeth, we observed that after the first erosive challenge with Coca-Cola®, a significantly greater hardness loss was seen in deciduous (-90.2 ± 11.3 VHN) than in permanent enamel (-44.3 ± 12.2 VHN; p = 0.007), but no differences between the two types of teeth were observed after two challenges (SH4 min). After both erosive challenges, all substances except for mineral water caused a significant loss in relative surface reflectivity intensity, and most substances caused a significant loss in surface hardness. Multiple regression analyses showed that pH, TA and Ca concentration play a significant role in initial erosion of deciduous enamel. We conclude that drinks, foodstuffs and medications commonly consumed by children can cause erosion of deciduous teeth and erosion is mainly associated with pH, titratable acidity and calcium

Segmentation of teeth in CT volumetric dataset by panoramic projection and variational level set

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Hosntalab, Mohammad [Islamic Azad University, Faculty of Engineering, Science and Research Branch, Tehran (Iran); Aghaeizadeh Zoroofi, Reza [University of Tehran, Control and Intelligent Processing Center of Excellence, School of Electrical and Computer Engineering, College of Engineering, Tehran (Iran); Abbaspour Tehrani-Fard, Ali [Islamic Azad University, Faculty of Engineering, Science and Research Branch, Tehran (Iran); Sharif University of Technology, Department of Electrical Engineering, Tehran (Iran); Shirani, Gholamreza [Faculty of Dentistry Medical Science of Tehran University, Oral and Maxillofacial Surgery Department, Tehran (Iran)

2008-09-15

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step. In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours. The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method. In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques. (orig.)

Segmentation of teeth in CT volumetric dataset by panoramic projection and variational level set

International Nuclear Information System (INIS)

Hosntalab, Mohammad; Aghaeizadeh Zoroofi, Reza; Abbaspour Tehrani-Fard, Ali; Shirani, Gholamreza

2008-01-01

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step. In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours. The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method. In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques. (orig.)

Doubly differential single and multiple ionization of krypton by electron impact

International Nuclear Information System (INIS)

Lucio, O. G. de; Gavin, J.; DuBois, R. D.

2007-01-01

Differential measurements for single and multiple ionization of Kr by 240 and 500 eV electron impact are presented. Using a pulsed extraction field, Kr + , Kr 2+ , and Kr 3+ ions were measured in coincidence with scattered electrons for energy losses up to 120 eV and scattering angles between 16 degree sign and 90 degree sign . Scaling properties of the doubly differential cross sections (DDCS) are investigated as a function of energy loss, scattering angle, and momentum transfer. It is shown that scaling the DDCS as outlined by Kim and Inokuti and plotting them versus a parameter consisting of the momentum transfer divided by the square root of the impact energy times 1-cos(θ), where θ is the scattering angle, yielded similar curves, but with different magnitudes, for single and multiple ionization. Normalizing these curves together produced two universal curves, one appropriate for single and multiple electron emission at larger scattering angles (θ≥30 degree sign ) and one appropriate for small scattering angles (θ<30 degree sign )

Teaching parents to look after children's teeth.

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Lloyd, S

1994-03-01

Children's toothpastes with fluoride help to prevent decay, but parents should ask their dentist before giving fluoride supplements to children. Overdosage is harmful. Sugars eaten as part of a meal do less harm to teeth than those eaten frequently as snacks. Sugar-free infant drinks and children's confectionery are now on the market and are more "tooth friendly". Look out for the "happy tooth" symbol. Babies can be registered with NHS dentists as soon as the first teeth start to come through, and should be taken regularly to the dentist throughout childhood. Under the NHS scheme, dentists are paid a capitation fee to provide continuing preventive care and treatment for children free of charge.

Aesthetic treatment of discoloration of nonvital teeth.

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Miara, P

1995-09-01

Attempts to treat discoloration in nonvital teeth were first reported a century ago. This article discusses two potential causes of nonvital tooth discoloration-trauma and endodontic treatment-along with a step-by-step clinical procedure for treatment of the discoloration. In trauma, hemoglobin is released into the tissues; iron oxides, formed by oxygen and iron in hemoglobin, cause discoloration and swelling that infringes on pulp space, forcing the pulp to recede with a potential loss of tooth vitality. After endodontic treatment, either hemorrhaging, materials used, or incomplete removal and breakdown of necrotic tissue may cause staining. The learning objective of this article is to review the causes and the prevention/treatment of discoloration in nonvital teeth.

Overdentures on natural teeth: a new approach.

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Previgliano, V; Barone Monfrin, S; Santià, G; Preti, G

2004-01-01

The study presents a new type of copings for overdentures on natural teeth. A new type of custom-made copings was prepared on 10 extracted teeth and their marginal fit was observed microscopically by means of a mechanical device, and software was employed to measure the gap. The marginal fit evaluation gave satisfactory values with mean values of the gap measurements below the clinically accepted limits (mean gap: 25.3 microm; minimum 7.3 microm, maximum 56.5 microm). The advantages of these new copings are: the rapidity of their preparation; the protection of the root canal treatment, because the coping with this chair-side method is prepared and cemented in one session; the low costs.

Changes in interdental papillae heights following alignment of anterior teeth.

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Kandasamy, Sanjivan; Goonewardene, Mithran; Tennant, Marc

2007-05-01

Orthodontic alignment of overlapped incisors can reduce the apparent heights of the interdental papillae leading to unsightly dark triangles or open gingival embrasures. To determine if certain pretreatment contact point relationships between the maxillary anterior teeth were accompanied by changes in the heights of the interdental papillae after orthodontic alignment. Pre- and post-treatment intra-oral 35 mm slides, lateral cephalometric radiographs and study casts of 143 patients (60 males, 83 females) between 13 and 16 years of age were used. The patients had diastamata closed, imbricated teeth aligned and palatally or labially placed teeth repositioned. A sample of 25 patients (12 males, 13 females) between 13 and 16 years of age who had well-aligned anterior teeth at the start of treatment acted as a control group. All patients were treated for approximately 18 months. The clinical crowns of the maxillary incisors and the heights of the interdental papilla between the incisors were measured on projected images of the slides. The percentage increases or reductions in the heights of the interdental papillae were compared. The heights of the interdental papillae increased following palatal movement of labially placed (p teeth and the intrusion of one tooth relative to another. On the other hand, dark triangles are more likely to develop following labial movement of imbricated or palatally placed incisors and closure of a diastema. Clinicians should be alert to the possibility of dark triangles developing in the latter group, particularly in older patients.

Crack arrest within teeth at the dentinoenamel junction caused by elastic modulus mismatch.

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Bechtle, Sabine; Fett, Theo; Rizzi, Gabriele; Habelitz, Stefan; Klocke, Arndt; Schneider, Gerold A

2010-05-01

Enamel and dentin compose the crowns of human teeth. They are joined at the dentinoenamel junction (DEJ) which is a very strong and well-bonded interface unlikely to fail within healthy teeth despite the formation of multiple cracks within enamel during a lifetime of exposure to masticatory forces. These cracks commonly are arrested when reaching the DEJ. The phenomenon of crack arrest at the DEJ is described in many publications but there is little consensus on the underlying cause and mechanism. Explanations range from the DEJ having a larger toughness than both enamel and dentin up to the assumption that not the DEJ itself causes crack arrest but the so-called mantle dentin, a thin material layer close to the DEJ that is somewhat softer than the bulk dentin. In this study we conducted 3-point bending experiments with bending bars consisting of the DEJ and surrounding enamel and dentin to investigate crack propagation and arrest within the DEJ region. Calculated stress intensities around crack tips were found to be highly influenced by the elastic modulus mismatch between enamel and dentin and hence, the phenomenon of crack arrest at the DEJ could be explained accordingly via this elastic modulus mismatch. Copyright 2010 Elsevier Ltd. All rights reserved.

Outcome of endodontic treatment of teeth filled using lateral condensation versus vertical compaction (Schilder's technique).

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Aqrabawi, Jamal A

2006-02-15

The purpose of this prospective clinical and radiographic investigation was to assess the treatment results following endodontic therapy of teeth filled with lateral condensation versus teeth filled with vertical compaction of warm gutta-percha. A total of 290 patients were treated using the standardized step-back technique for canal preparation, which were filled with either lateral condensation or vertical compaction in one single session. Five years later, the treatment results were assessed clinically and radiographically and related to the type of the obturation technique using Chi-square analysis. Of the 340 teeth that were reexamined, 160 teeth were filled with lateral condensation, and 180 teeth were filled with vertical condensation. The results showed a significantly higher success rate for the vertical compaction versus the lateral condensation technique of teeth presented with preoperative periapical lesions P<0.04. Regardless of the preoperative periapical status of the teeth, no statistically significant difference was found between the two techniques. The overall success rate of both filling techniques was 80.3%.

A novel mutation of adenomatous polyposis coli (APC) gene results in the formation of supernumerary teeth.

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Yu, Fang; Cai, Wenping; Jiang, Beizhan; Xu, Laijun; Liu, Shangfeng; Zhao, Shouliang

2018-01-01

Supernumerary teeth are teeth that are present in addition to normal teeth. Although several hypotheses and some molecular signalling pathways explain the formation of supernumerary teeth, but their exact disease pathogenesis is unknown. To study the molecular mechanisms of supernumerary tooth-related syndrome (Gardner syndrome), a deeper understanding of the aetiology of supernumerary teeth and the associated syndrome is needed, with the goal of inhibiting disease inheritance via prenatal diagnosis. We recruited a Chinese family with Gardner syndrome. Haematoxylin and eosin staining of supernumerary teeth and colonic polyp lesion biopsies revealed that these patients exhibited significant pathological characteristics. APC gene mutations were detected by PCR and direct sequencing. We revealed the pathological pathway involved in human supernumerary tooth development and the mouse tooth germ development expression profile by RNA sequencing (RNA-seq). Sequencing analysis revealed that an APC gene mutation in exon 15, namely 4292-4293-Del GA, caused Gardner syndrome in this family. This mutation not only initiated the various manifestations typical of Gardner syndrome but also resulted in odontoma and supernumerary teeth in this case. Furthermore, RNA-seq analysis of human supernumerary teeth suggests that the APC gene is the key gene involved in the development of supernumerary teeth in humans. The mouse tooth germ development expression profile shows that the APC gene plays an important role in tooth germ development. We identified a new mutation in the APC gene that results in supernumerary teeth in association with Gardner syndrome. This information may shed light on the molecular pathogenesis of supernumerary teeth. Gene-based diagnosis and gene therapy for supernumerary teeth may become available in the future, and our study provides a high-resolution reference for treating other syndromes associated with supernumerary teeth. © 2017 The Authors. Journal of

Improvement of age estimation using amino acid racemization in a case of pink teeth.

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Ohtani, S; Yamada, Y; Yamamoto, I

1998-03-01

Age was estimated from pink teeth using racemization of dentinal aspartic acid. Materials for identification were two lower second premolars. The body was determined to be that of a 40-year-old man; however, the age of the decedent had been estimated to be 29 and 30 years by the conventional method and 30 years from findings in the oral cavity. To clarify the cause of this difference, the powdered teeth were further washed in 0.01 mol/L hydrochloric acid. The racemization ratio (D/L ratio) of ordinary white teeth from persons of known age was slightly lower than that before washing, whereas that of the teeth used for identification was higher than before washing. The calculated age of the decedent using the racemization ratio of his teeth was between 36 and 37 years. These results suggest that age estimated from pink teeth is probably underestimated, but a more accurate age estimate can be obtained after adequate washing.

TREATMENT APPROACHES FOR TRAUMATIZED ANTERIOR TEETH WITH EXCESSIVE TISSUE LOSS: THREE CASE REPORTS

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Zuhal YILDIRIM

2017-04-01

Full Text Available Use of direct composite and indirect laminate veneers has been an alternative to metal- and all-ceramic crowns for anterior teeth restorations. Dental traumas are the most common reasons for excessive tissue loss. Treatment options depend on the amount of remaining tissue, the extent of the damage to dental pulp and periapical tissues and the time elapsed before dental treatment. The aim of this case report was to evaluate the direct and indirect techniques used in the treatments of traumatically fractured anterior teeth. In Case 1, a 29-year-old male patient attended to the clinics of the Department of Restorative Dentistry, Faculty of Dentistry, Istanbul University for the replacement of old composite restorations. According to anamnesis, the anterior teeth had fractured because of falling from bicycle. Dentinal pins used to retain the composite restorations were screwed out and indirect composite laminate veneers were placed. In Case 2, a 27-year-old male patient attended to our clinic for the treatment of his anterior teeth which were fractured due to a fall. A different type of technique, a silicon guide, was used to mimic the natural teeth surfaces precisely. In Case 3, a 16-year-old female patient attended to our clinic for the treatment of her anterior teeth which were fractured in a car accident. On clinical evaluation, related teeth were found to be non-vital and application of fiber posts was considered suitable before direct composite restorations. In conclusion, all of these techniques may be used for traumatized anterior teeth. Esthetical necessities and functional forces should be taken into consideration in material choice.

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

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Weihua Shi

Full Text Available 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 in the same healthy oral cavity.Supragingival plaque samples of teeth in various locations-the first permanent molars, deciduous molars, deciduous canines and incisors and permanent incisors-were collected from 20 healthy mixed-dentition-stage children with 10-12 permanent teeth erupted. Plaque DNA was extracted, and the V3-V4 hypervariable region of the bacterial 16S rRNA gene was amplified and subjected to sequencing.On average, 18,051 high-quality sequences per sample were generated. Permanent tooth sites tended to host more diverse bacterial communities than those of deciduous tooth sites. A total of 12 phyla, 21 classes, 38 orders, 66 families, 74 genera were detected ultimately. Five predominant phyla (Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria and Actinobacteria were highly variable among sites. Of 26 genera with a mean relative abundance of >0.1%, 16 showed significant differences in relative abundance among the groups. More than 20% of the total operational taxonomical units were detected only in permanent or deciduous teeth. The variation in the microbial community composition was due mainly to permanent teeth being enriched in Actinomyces and deciduous teeth in Treponema. The core microbiome of supragingival plaque in mixed dentition comprised 19 genera with complex correlationships.Our results suggest differences in microbial diversity and composition between permanent and deciduous teeth sites in mixed dentition. Moreover, the core microbiome of these sites was determined. These findings enhance our understanding of the development of the native oral microbiota with age.

Root fracture in immature anterior teeth followed for 15 years.

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Itoh, T; Kojima, Y; Nishioka, T; Maki, K; Kimura, M

2005-08-01

We report a case of injury to an immature tooth, observed over a period of 15 years. In 1987, a 9-year-old boy fell down in a schoolyard. The right central incisor demonstrated palato-version and radiographic observations revealed that the roots of both central incisors were incomplete. Further, a root fracture in the apical region of the central incisors was observed. During the first treatment visit, the right central incisor was repositioned and both teeth splinted. After confirming that the line of fracture was aligned, the fixation was continued for 2 months. The teeth were examined periodically for the next 15 years. Both teeth had favorable outcomes with continued root development of both the apical and coronal segments with good apposition of the fracture lines.

Disinfection/sterilization of extracted teeth for dental student use.

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Dominici, J T; Eleazer, P D; Clark, S J; Staat, R H; Scheetz, J P

2001-11-01

Extracted human teeth are used in many preclinical courses. While there has been no report of disease transmission with extracted teeth, sterilization of teeth used in the teaching laboratory should be a concern. The purpose of this study was to determine the effectiveness of different sterilization/disinfection methods of extracted human teeth using Bacillus stearothermophilus, a bacteria resistant to heat and frequently used to test sterilizers. In this study, 110 extracted molars with no carious lesions were collected and stored in buffered saline. An endodontic occlusal access preparation was cut into the pulp chamber of each tooth. Pulp tissue in the chamber was removed with a broach. Approximately 1 x 10(5) B. stearothermophilus endospores in culture medium were injected into the pulp chamber, sealed with Cavit G, and then placed in sterile saline for twelve hours. Ten teeth were placed into each of eleven groups. Seven groups were immersed for one week in one of the following solutions: a) sterile saline (control group), b) 5.25% NaOCl, c) 2.6% NaOCl, d) 1% NaOCl, e) 10% buffered formalin, f) 2% gluteraldehyde, g) 0.28% quaternary ammonium. Four additional groups were treated by h) 10% formalin for two days, i) 10% formalin for four days, j) autoclaving at 240 degrees F and 20 psi for twenty minutes, and k) autoclaving at 240 degrees F and twenty psi for forty minutes. Each tooth was then aseptically split and placed in an individual test tube with growth medium. Samples were examined for evidence of growth (turbidity) at forty-eight hours. Only autoclaving for forty minutes at 240 degrees F and 20 psi or soaking in 10 percent formalin for one week were 100 percent effective in preventing growth. A chi-square analysis of the data indicates these two methods were significantly better than all other methods (p<0.001).

An exploratory study of human teeth enamel by using Ft-Raman spectroscopy

International Nuclear Information System (INIS)

Afishah Alias; Siti Rahayu Mohd Hashim; Mihaly, Judith; Julyannie Wajir; Fauziah Abdul Aziz

2009-01-01

Unaffected , affected and heavily affected teeth enamel were studied by using FT-Raman spectroscopy. The 14 permanent teeths enamel surface were measured randomly, resulting in total n = 43 FT-Raman spectra. The results obtained from FT-Raman spectra of heavily affected, affected and unaffected tooths enamel surfaces did not show any significant difference. In this study, Kruskal-Wallis and Wilcoxon rank sum tests were used to compare the intensity between the categories of enamel as well as the surfaces of teeth samples. (author)

[Results of treatment of milk teeth pulp by modified formocresol method].

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Wochna-Sobańska, M

1989-01-01

The purpose of the study was evaluation of the results of treatment of molar pulp diseases by the formocresol method from the standpoint of the development of inflammatory complications in periapical tissues, disturbances of physiological resorption of roots, disturbances of mineralization of crowns of homologous permanent teeth. For the treatment milk molars were qualified with the diagnosis of grade II pulpopathy in children aged from 3 to 9 years. The treatment was done using formocresol by a modified method of pulp amputation according to Buckley after previous devitalization with parapaste. The status of 143 teeth was examined again 1 to 4 years after completion of treatment. The proportion of positive results after one year was 94%, after two years it was 90%, after three years 87% and after four years 80%. The cause of premature loss of most teeth was root resorption acceleration by 18-24 months. No harmful action of formocresol on the buds of permanent teeth was noted.

Apoptosis in the human periodontal membrane evaluated in primary and permanent teeth

DEFF Research Database (Denmark)

Bille, Marie-Louise Bastholm; Thomsen, Bjarke; Kjær, Inger

2011-01-01

that resorption is connected to apoptosis of the epithelial cells of Malassez. The purpose of this study is to localize cells undergoing apoptosis in the periodontal membrane of human primary and permanent teeth. Materials and methods. Human primary and permanent teeth were examined immunohistochemically...... for apoptosis and epithelial cells of Malassez in the periodontal membrane. All teeth examined were extracted in connection with treatment. Results. Apoptosis was seen in close proximity to the root surface and within the epithelial cells of Malassez. This pattern of apoptotis is similar in the periodontal...... membrane in primary and permanent teeth. Conclusions. The inter-relationship between apoptotis and root resorption cannot be concluded from the present study. Apoptosis seen in close proximity to the root surface presumably corresponds to the highly innervated layer of the periodontal membrane...

Do general dental practitioners leave teeth on 'open drainage'?

Science.gov (United States)

Eliyas, S; Barber, M W; Harris, I

2013-12-01

There is a need to ascertain the use of evidence-based dentistry in both primary and secondary care in order to tailor education. This study aims to evaluate the use of 'open drainage' as part of endodontic treatment in primary care in South Yorkshire. A questionnaire was circulated to 141 randomly selected general dental practitioners in the South Yorkshire area between January 2012 and January 2013. The response rate was 79% (112/141). Five of the returned questionnaires were incomplete and therefore not usable. Seventy-nine percent of respondents were general dental practitioners (GDPs) working in mainly NHS or mixed practices. The year of graduation varied between 1970 and 2011. Forty-one percent (44/107) stated that they had never left a tooth on open drainage. Twenty-nine percent (31/107) stated that they sometimes leave teeth on open drainage. Of those respondents who currently leave teeth on open drainage, most (68%) would leave teeth on open drainage for one to two days or less. This survey revealed that the practice of leaving teeth on open drainage is still present in general dental practice. Current guidelines do not comment on the use of this treatment modality. There is a need to ascertain further information about practices throughout the United Kingdom in order to provide clear evidence-based guidelines.

Prevalence, Characteristics, and Complications of Supernumerary Teeth in Nonsyndromic Pediatric Population of South India: A Clinical and Radiographic Study.

Science.gov (United States)

Syriac, Gibi; Joseph, Elizabeth; Rupesh, S; Philip, John; Cherian, Sunu Alice; Mathew, Josey

2017-11-01

Supernumerary teeth are the presence of more number of teeth over the normal dental formula and may occur in permanent as well as early mixed dentition. This study determined the prevalence, characteristics, and complications caused by supernumerary teeth in nonsyndromic South Indian pediatric population. Characteristics of supernumerary teeth determined by clinical and radiographic examination were recorded. The age, sex, number of supernumerary teeth, eruption status, morphology, position, orientation, and complications (if any) associated with supernumerary teeth were recorded for each patient who had supernumerary teeth. The data collected were statistically analyzed. Supernumerary teeth were detected in 45 subjects (1.1%), of which 34 (75.6%) were male and 11 (24.4%) were female. There was no association between the number of supernumerary teeth and the gender of the patient. The total number of supernumerary teeth among the affected 45 patients was 54. The average number of supernumerary teeth per person was 1.2. The number of supernumerary teeth was one in 35 cases, two in 8 cases, and 3 in 1 case. Of the 45 patients, 8 patients with supernumerary teeth were in deciduous dentition stage, 29 patients were in mixed dentition stage, and 8 patients were in permanent dentition stage. Most supernumerary teeth presented in the anterior maxilla. Morphologically, conical-shaped supernumerary teeth were the most common finding. 68.5% of supernumerary teeth presented with straight orientation and inverted orientation was seen in 24.1%. Complications seen in patients with supernumerary teeth were delayed or noneruption of adjacent tooth malposition or rotation of adjacent teeth, diastema formation, and formation of dentigerous cyst. Supernumerary teeth have an incidence of 1.1% in South Indian population and can cause many complications that can harm the developing occlusion. Knowledge about supernumerary teeth may help the dentist in early diagnosis and early

Dental Pulp Revascularization of Necrotic Permanent Teeth with Immature Apices.

Science.gov (United States)

El Ashiry, Eman A; Farsi, Najat M; Abuzeid, Sawsan T; El Ashiry, Mohamed M; Bahammam, Hammam A

The treatment of immature necrotic teeth with apical periodontitis presents challenges in endodontic and pediatric dentistry. Revascularization is a recent treatment for such cases as an alternative to conventional apexification. The purpose is to examine the effect of a pulpal revascularization procedure on immature necrotic teeth with apical periodontitis. Twenty patients were enrolled for pulp revascularization procedure by root canal disinfection using a triple antibiotic mixture for 1-2 weeks, followed by creating a blood clot, sealing the root canal orifice using white mineral trioxide aggregate and a coronal seal of composite resin. Patients were recalled periodically for up to 24 months. During follow-up, all patients were asymptomatic. Three cases of chronic apical periodontitis showed clinical disappearance of the sinus tract 2 weeks after treatment. Radiography revealed progressive periapical radiolucency resolution within the first 12 months. Within 12-24 months, the treated teeth showed progressive increases in dentinal wall thickness, root length and continued root development. Clinical and radiographic evidence showed successful revascularization treatments of immature necrotic permanent teeth with apical periodontitis. More studies are necessary to understand the underlying mechanisms and to perform histopathology of the pulp space contents after revascularization procedures.

Mounting ground sections of teeth: Cyanoacrylate adhesive versus Canada balsam.

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Vangala, Manogna Rl; Rudraraju, Amrutha; Subramanyam, R V

2016-01-01

Hard tissues can be studied by either decalcification or by preparing ground sections. Various mounting media have been tried and used for ground sections of teeth. However, there are very few studies on the use of cyanoacrylate adhesive as a mounting medium. The aim of our study was to evaluate the efficacy of cyanoacrylate adhesive (Fevikwik™) as a mounting medium for ground sections of teeth and to compare these ground sections with those mounted with Canada balsam. Ground sections were prepared from twenty extracted teeth. Each section was divided into two halves and mounted on one slide, one with cyanoacrylate adhesive (Fevikwik™) and the other with Canada balsam. Scoring for various features in the ground sections was done by two independent observers. Statistical analysis using Student's t-test (unpaired) of average scores was performed for each feature observed. No statistically significant difference was found between the two for most of the features. However, cyanoacrylate was found to be better than Canada balsam for observing striae of Retzius (P < 0.0205), enamel lamellae (P < 0.036), dentinal tubules (P < 0.0057), interglobular dentin (P < 0.0001), sclerotic dentin - transmitted light (P < 0.00001), sclerotic dentin - polarized light (P < 0.0002) and Sharpey's fibers (P < 0.0004). This initial study shows that cyanoacrylate is better than Canada balsam for observing certain features of ground sections of teeth. However, it remains to be seen whether it will be useful for studying undecalcified sections of carious teeth and for soft tissue sections.

Infant teething information on the world wide web: taking a byte out of the search.

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Kozuch, Mary; Peacock, Erica; D'Auria, Jennifer P

2015-01-01

The purpose of this study was to describe and evaluate the quality of infant teething information on selected popular parenting Web sites. Two checklists were used to evaluate the quality of the 16 parenting sites and infant teething-specific content included on each site. Three of the 16 parenting sites did not contain teething-specific articles. Teething-specific content found on 13 of the 16 sites supported a connection between the process of teething and nonspecific symptoms with a perception that management is required. Popular management strategies included chewing on chilled objects, gingival massage, and the use of over-the-counter medications. Information about possible adverse effects of administering medications for infant teething was not found on the majority of sites. Eleven of the 16 sites advised parents to contact their primary care provider if they were uncertain about management for infant teething or whether the symptoms were related to illness. Although infant teething has an evidence base from which parents and professionals can make safe decisions about symptoms and treatment, translating the evidence into professional practice and health-related information on the Internet remains a challenge. Parents and pediatric health providers would benefit greatly from the development of clinical practice guidelines summarizing our present-day understanding of teething symptoms and the limited evidence supporting the use of over-the-counter medications. Copyright © 2015 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.

Biologically based treatment of immature permanent teeth with pulpal necrosis: a case series.

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Jung, Il-Young; Lee, Seung-Jong; Hargreaves, Kenneth M

2012-06-01

This case series reports the outcomes of 8 patients (ages 9-4 years) who presented with 9 immature permanent teeth with pulpal necrosis and apical periodontitis. During treatment, 5 of the teeth were found to have at least some residual vital tissue remaining in the root canal systems. After NaOCI irrigation and medication with ciprofloxacin, metronidazole, and minocycline, these teeth were sealed with mineral trioxide aggregate and restored. The other group of 4 teeth had no evidence of any residual vital pulp tissue. This second group of teeth was treated with NaOCl irrigation and medicated with ciprofloxacin, metronidazole, and minocycline followed by a revascularization procedure adopted from the trauma literature (bleeding evoked to form an intracanal blood clot). In both groups of patients, there was evidence of satisfactory postoperative clinical outcomes (1-5 years); the patients were asymptomatic, no sinus tracts were evident, apical periodontitis was resolved, and there was radiographic evidence of continuing thickness of dentinal walls, apical closure, or increased root length.

Effect of amalgam cuspal coverage on the fracture resistance of endodontically treated teeth

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Mahshid Mohammdi Basir

2013-05-01

Full Text Available   Background and Aims: Endodontically treated teeth are prone to fracture because they loose a big amount of their structure. The treatment plan of those teeth is completed when they are rehabilitated with a strong and functional restoration. The purpose of this study was to evaluate the fracture resistance of endodontically treated teeth restored with amalgam cuspal coverage in comparison with other restorative techniques.   Materials and Methods: 40 human healthy maxillary premolars were divided into 4 groups: group1 (S: sound teeth, group 2(Co: endodontically treated teeth with MOD cavity restored with bonding and composite, group 3(Am-B: endodontically treated teeth with MOD cavity restored with bonding and amalgam and group 4 (Am-CC: endodontically treated teeth with MOD cavity restored with amalgam cuspal coverage. Then the restorations were stored in water and room temperature for 100 days at then thermocycled for 500 cycles between water baths at (5.5 ± 1 and (55 ± 1 0 C. The fracture resistance was evaluated by universal testing machine (Instron, 1195 UK with the compressive force of about 2000 N in 0.5 mm/min. The fracture modes were evaluated in four groups by a stereomicroscope. Statistical analysis (Scheffe test was done for all groups (P0.05. The lowest fracture resistance was found in group 2 (Co (384 ± 137.4 N that had no significant difference with group 3 (Am-B (P>0.05. The fracture resistance in group 4 was significantly higher than group 2 (Co and 3 (Am-B. The fracture mode in group 1 was cohesive within tooth and in group 2 (Co and 3 (Am-B was mixed cohesive and adhesive, and in group 4 was cohesive within in restorative material.   Conclusion: The highest fracture resistance was found in teeth that received amalgam cuspal coverage.

The significance of biometric parameters in determining anterior teeth width

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Strajnić Ljiljana

2013-01-01

Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

Non-masticatory uses of anterior teeth of Sima de los Huesos individuals (Sierra de Atapuerca, Spain).

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Lozano, Marina; Bermúdez de Castro, José M; Carbonell, Eudald; Arsuaga, Juan Luis

2008-10-01

In this study we examine the labial and occlusal surfaces of incisors and canines of hominins recovered from the Sima de los Huesos (SH), middle Pleistocene site, in order to establish the possible extra-masticatory use of anterior teeth. We have compared the microwear of these fossils with microwear from the anterior teeth of Australian Aborigines, a population characterized by ethnographic evidence of the use of their teeth as a third hand. These two samples of teeth were microscopically analyzed using Scanning Electron Microscopy (SEM). Our results support the "cultural" origin of microwear observed on fossil teeth: we conclude that the SH hominins used their anterior teeth as a "third hand" for para- or extra-masticatory activities.

[Overdenture supported by natural teeth: analysis of clinical advantages].

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Scotti, R; Melilli, D; Pizzo, G

2003-05-01

Hybrid prosthesis supported by natural teeth (overdenture) is widely used in clinical practice and should be executed whenever the clinical conditions suggest it. Through a critical review of the literature, the anatomical, functional, psychological and clinical advantages are emphasized. Among the first ones, the prophylaxis of residual anatomical components, due to the limitation of bone resorption, and the preservation of sensorial proprioception are relevant. Important advantages are also represented by a better crown-root ratio of residual teeth supporting overdenture, with the consequent improvement of the longitudinal prognosis of such teeth. The greater retention and stability of overdenture in comparison with complete denture greatly improve the masticatory efficacy. The psychological advantages resulting from the dental anchorage, which allows the patient to be more confident in social life, are also relevant. Finally, when the dental support is lost, converting overdenture into complete denture is simple and quick, and makes easier the longitudinal clinical maintenance of the denture.

Opalescence of human teeth and dental esthetic restorative materials.

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Lee, Yong-Keun

2016-12-01

Human tooth enamel is opalescent, which renders teeth bluish in reflected and orange in transmitted color. The aim was to review opalescent property of teeth and application and mimetic reproduction in esthetic restorations. A PubMed search for articles published in English till 2015 on the opalescence of teeth and esthetic materials revealed 29 relevant papers. Opalescence was measured with OP-RT index, which was calculated as the difference in the yellow-blue and red-green color coordinates between the reflected and transmitted colors. Mean OP-RT value of human enamel was 22.9. OP-RT values of direct resin composites changed after polymerization, and the range in these materials was 5.7-23.7. OP-RT value ranges were 1.6-6.1 and 2.0-7.1 for the core and veneer ceramics, respectively. Since the OP-RT values of esthetic materials were lower than that of enamel, it is recommended that materials that can reproduce the opalescence of enamel be further designed.

Mapping the structure, composition and mechanical properties of human teeth

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Low, I.M.; Duraman, N.; Mahmood, U.

2008-01-01

The structure-property relationship in human adult and baby teeth was characterised by grazing-incidence synchrotron radiation diffraction, optical and atomic-force microscopy, in addition to Vickers indentation. Similarities and differences between both types of teeth have been highlighted and discussed. Depth-profiling results indicated the existence of contrasting but distinct gradual changes in crystal disorder, phase abundance, crystallite size and hardness within the baby and adult enamel, thus confirming the graded nature of human teeth. When compared to the adult tooth, the baby enamel is softer, more prone to fracture, but has larger hydroxyapatite grains. Vickers hardness of the enamel was load-dependent but load-independent in the dentine. The use of a 'bonded-interface' technique revealed the nature and evolution of deformation-microfracture damage around and beneath Vickers contacts

Mapping the structure, composition and mechanical properties of human teeth

Energy Technology Data Exchange (ETDEWEB)

Low, I.M. [Materials Research Group, Department of Applied Physics, Curtin University of Technology, Perth, WA 6845 (Australia)], E-mail: j.low@curtin.edu.au; Duraman, N.; Mahmood, U. [Materials Research Group, Department of Applied Physics, Curtin University of Technology, Perth, WA 6845 (Australia)

2008-03-10

The structure-property relationship in human adult and baby teeth was characterised by grazing-incidence synchrotron radiation diffraction, optical and atomic-force microscopy, in addition to Vickers indentation. Similarities and differences between both types of teeth have been highlighted and discussed. Depth-profiling results indicated the existence of contrasting but distinct gradual changes in crystal disorder, phase abundance, crystallite size and hardness within the baby and adult enamel, thus confirming the graded nature of human teeth. When compared to the adult tooth, the baby enamel is softer, more prone to fracture, but has larger hydroxyapatite grains. Vickers hardness of the enamel was load-dependent but load-independent in the dentine. The use of a 'bonded-interface' technique revealed the nature and evolution of deformation-microfracture damage around and beneath Vickers contacts.

Evaluation of thermal cooling mechanisms for laser application to teeth.

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Miserendino, L J; Abt, E; Wigdor, H; Miserendino, C A

1993-01-01

Experimental cooling methods for the prevention of thermal damage to dental pulp during laser application to teeth were compared to conventional treatment in vitro. Pulp temperature measurements were made via electrical thermistors implanted within the pulp chambers of extracted human third molar teeth. Experimental treatments consisted of lasing without cooling, lasing with cooling, laser pulsing, and high-speed dental rotary drilling. Comparisons of pulp temperature elevation measurements for each group demonstrated that cooling by an air and water spray during lasing significantly reduced heat transfer to dental pulp. Laser exposures followed by an air and water spray resulted in pulp temperature changes comparable to conventional treatment by drilling. Cooling by an air water spray with evacuation appears to be an effective method for the prevention of thermal damage to vital teeth following laser exposure.

Natural tooth pontic with splinting of periodontally weakened teeth using fiber-reinforced composite resin

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Gauri Srinidhi

2014-01-01

Full Text Available Replacement of missing anterior teeth due to periodontal reasons is challenging due to the poor support of abutment teeth. This prevents the use of fixed partial dentures (FPDs. Fiber-reinforced splinting provides a viable alternative to the dentist while choosing a treatment plan in replacing missing anterior teeth in periodontally compromised patients as opposed to conventional modalities like FPDs or removable partial dentures. Replacing missing teeth using either patient′s own tooth or a denture tooth as pontic can be done by splinting adjacent teeth with fiber reinforced composite. The splinting has an additional advantage of stabilizing adjacent mobile teeth. This case report details the case selection, procedure with follow-up of a case where the natural extracted tooth of the patient was used as pontic to replace a missing anterior tooth. The splinting was done with fiber reinforced composite resin. Fiber-reinforced composite resin splinting of patient′s extracted natural tooth is economical, fast, and easy to use chairside technique with the added benefit of periodontal stabilization.

Relationship between width and length ratios of upper anterior teeth in young Chilean population.

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Jorge Troncoso-Pazos

2017-08-01

Full Text Available Introduction: Knowledge about the size and proportion of upper anterior teeth allows dental rehabilitation taking into consideration the local parameters of a population. The aim of this research is to determine the width, length and the relationship between width and length of central incisor, lateral incisor and canine teeth in both sexes in young Chilean population. Methodology: A cross-sectional study was performed. Study subjects included 187 dentistry students from two Chilean cities (mean age 21.35±2.7 years, 52.9% men. The teeth width and height were measured and the width/height ratio was calculated. Differences in measurements according to sex was analyzed (p<0.05; STATA v.10.0. Results: The width and height of the teeth were statistically and proportionally larger in men (p<0.05. The width/height ratio of lateral and canine incisors was significantly higher in women (p<0.05. Conclusion: In a sample of young Chileans, upper anterior teeth were longer and wider in men. However, the width/height ratio of teeth was found to be significantly higher in women.

Occlusal plane change after intrusion of maxillary posterior teeth by microimplants to avoid maxillary surgery with skeletal Class III orthognathic surgery.

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Park, Hyo-Sang; Kim, Ji-Yeun; Kwon, Tae-Geon

2010-11-01

To increase stability and mandibular setback movement, surgical maxillary impaction is normally performed with mandibular setback surgery in treating adult skeletal Class III patients. This article demonstrates the use of microimplants for anchorage to intrude molars and the resultant rotation of the maxillary occlusal plane clockwise to increase the surgical mandibular setback and reduce the posterior vertical dimension instead of maxillary surgical impaction. A 21-year-old man with mandibular prognathism was treated with mandibular setback surgery that included orthodontic treatment for decompensation. Microimplants placed into the palatal alveolar bone between the maxillary first and second molars were used to intrude the maxillary posterior teeth and change the occlusal plane clockwise. This produced 4 mm more of distal movement of the chin during mandibular setback surgery compared with the surgical prediction with no change in the occlusal plane. These results were similar to those of 2-jaw surgery with maxillary posterior impaction. The intrusion of the maxillary posterior teeth with microimplants might prevent the need for maxillary surgery in adult skeletal Class III patients. Copyright © 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Characteristics of dental pulp in human upper first premolar teeth based on immunohistochemical and morphometric examinations.

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Tomaszewska, Joanna Maria; Miskowiak, Bogdan; Matthews-Brzozowska, Teresa; Wierzbicki, Piotr

2013-01-01

Teeth extracted for orthodontic reasons are commonly considered as healthy. Therefore, it is possible to examine structure of the dental pulp can be fully recognized and how it is affected by malocclusion. The aim of the study was to evaluate by immunohistochemistry (IHC) and morphometry dental pulp in human upper first premolar teeth extracted for orthodontic reasons. The material comprised 36 teeth of 20 patients in the age range 16-26 years. By the use of IHC markers the presence of immunocompetent cells (CD20, CD45RO, and CD68), blood vessels (CD31) and nerves (PGP9.5) were examined in the pulp. Inflammatory infiltrates and tissue atrophy were observed in 24 and 10 teeth, respectively. Strong positive correlation between the width of the odontoblastic layer, the number of rows of odontoblast nuclei and the increase of MVA (microvessel area) in the pulp of atrophic teeth was found. The cellular infiltrations found in H&E-stained sections were identified by IHC as memory T cells (CD45RO+) and B lymphocytes (CD20+) with macrophages (CD68+) present at the periphery. The CD20 antigen was intensively expressed in 13 teeth, CD45RO in 33 teeth, and CD68 in 20 teeth. Thus, despite the lack of any clinical signs of pulp disease many teeth extracted for orthodontic reasons show focal pulp inflammation and atrophy which probably results from the malocclusion stress accompanying teeth crowding.

Intravenous administration of puppy deciduous teeth stem cells in degenerative valve disease

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Soontaree Petchdee

2016-12-01

Full Text Available Aim: The objective of this study is to investigate the improvement of heart function in dogs with chronic valvular heart disease after puppy deciduous teeth stem cells (pDSCs administration. Materials and Methods: 20 client-owned dogs with degenerative valvular heart disease underwent multiple intravenous injections of allogeneic pDSCs. Dogs were randomly assigned to two groups: (i Control group (n=10 with standard treatment for heart failure and (ii group with standard treatment and multiple administrations of pDSCs (n=10. Electrocardiography, complete transthoracic echocardiography, thoracic radiography, and blood pressure were recorded before and after pDSCs injections for 15, 30 and 60 days. Results: Post pDSCs injection showed measurable improvement in left ventricular ejection fraction, American College of Veterinary Internal Medicine (ACVIM functional class significantly improved and improved quality of life scores were observed. In the control group, there were no significant enhancements in heart function or ACVIM class. Conclusions: This finding suggests that pDSCs could be a supplement for valvular heart disease treatment.

Chair time saving method for treatment of an impacted maxillary central incisor with 15-month follow-up

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Saeed Noorollahian

2018-01-01

Full Text Available Maxillary permanent incisors have a major role in facial esthetics. Impaction of them has great adverse effect on smile and causes serious concerns in patient and parents. Physical barriers (e.g., overretained primary teeth, supernumerary teeth, and pathologic lesions, space problems, developmental abnormalities, altered eruption sequence, trauma, palatal clefts, and genetics can act as etiologic factors. Currently, the conventional technique to treatment of impacted teeth consists of a combined orthodontic and surgical approach, to guide the impacted teeth in a constant position and surrounded by normal hard and soft tissues. Treatment is challenging because of some limitations such as patient's age, cooperation, anchorage, and mechanotherapy possibilities. Hence, sophisticated treatment planning is crucial. A 9-year-old girl with horizontally impacted maxillary left central incisor treated with surgical exposure and closed orthodontic forced eruption with 2 × 4 partial setup fixed appliances. Force was applied with 0.014 inch nickel–titanium wire as elastic overlay and handmade ligated bracket. To save chair time in each appointment, the overlay was activated by twisting of ligature wire extensions around it. After 16-month treatment, impacted incisor emerged in oral cavity, with accepted alignment and inclination. Handmade ligated bracket with ligature wire extensions is useful for the treatment of impacted teeth. Due to easy activation of overlay in this method, chair time become short in each appointment.

Expression and localization of special AT-rich sequence binding protein 2 in murine molar development and the pulp-dentin complex of human healthy teeth and teeth with pulpitis

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He, Lina; Liu, Huimei; Shi, Lei; Pan, Shuang; Yang, Xu; Zhang, Lin; Niu, Yumei

2017-01-01

Special AT-rich sequence binding protein 2 (SATB2) is a member of the special family of AT-rich binding transcription factors and has a critical role in osteoblast differentiation and craniofacial patterning. However, the expression and distribution of SATB2 in tooth development is largely unknown. The aim of the present study was to detect the expression and distribution of SATB2 during murine molar development and, in human healthy teeth and teeth with pulpitis using immunohistochemistry. Molars were obtained from Kunming mice at embryonic day (E) 13.5, E14.5, E16.5 and E18.5, and postnatal day (P) 1, P5 and P7. In addition, 20 human teeth (10 healthy and 10 teeth with pulpitis) were obtained from young adult patients (age, 24.90±1.65 years) who were scheduled for routine extraction. Immunohistochemical analyses were performed to detect the expression and distribution of SATB2. The present results revealed that SATB2 exhibits a spatiotemporal expression pattern in murine molar development and was expressed in odontoblasts, predentin, dental pulp cells and the blood vessels in human teeth. These findings suggested that SATB2 may have an important role in odontoblast differentiation and dentin matrix mineralization during tooth development. PMID:29042940

Lead levels in deciduous teeth of children in Yemen

International Nuclear Information System (INIS)

Ismail, Rokhsana M.

2001-01-01

To determine lead exposure among children in Yemen a total of 280 shed deciduous whole teeth were collected from 269 children. Teeth were analyzed for lead concentrations using atomic absorption spectrophotometry (SP9 Philips) with electrothermal atomization. Children were between 5 and 15 years old. The study period extended from April 1999 to August 2000. The study showed that the overall mean tooth - lead level was 2.15 mg/g dry weight with a range of 0.05-30.4 mg/g dry weight. (author)

Self-perception of teeth loss of the aged

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Beatriz Unfer

2006-01-01

Full Text Available The objective of this work was to analyze the perceptions of a group of the aged regarding teeth loss. A qualitative study was conducted using the Discourse of the Collective Subject as a methodological technique for ordering the data. The analysis of the interviews and the construction of the Discourse of the Collective Subject disclosed information on the thoughts and values associated with the loss of teeth within this group. The main results suggest that the lack of teeth caused functional and psychological problems, but that these appeared to be offset by solving the aesthetic problem. The justifications disclosed by the collective subject for edentulous predominantly reflect the healthcare model, which focuses on surgical, restorative and rehabilitation procedures, to the detriment of preventive actions and the promotion of health. Thus, the development of initiatives in the field of education and prevention regarding oral health is essential, emphasizing actions that target integral attention to the aged, detaching the social dimension of the illnesses, as well as the role of the State as supplier of health and quality of life to all citizens.

The mean visible labial length of maxillary and mandibular anterior teeth at rest

International Nuclear Information System (INIS)

Khan, F.; Abbas, M.

2014-01-01

To determine the mean visible labial length of maxillary and mandibular anterior teeth at rest. Study Design: Cross-sectional study. Place and Duration of Study: Department of Prosthodontics, Dr. Ishrat-ul-Ebad Khan Institute of Oral Health Sciences, Karachi, from October 2012 to March 2013. Methodology: A total of 200 subjects were included. Measurements were carried out using digital caliper from the border of the lip to the incisal edges of incisor and to the cusp tip for the canines. The length of the upper lip was measured from subnasale to stomion. Statistical analyses were performed by Mann Whitney-U test and Kruskal Walli's test. Results: The age of the participant ranged between 20 and 65 years. At rest, females significantly displayed more of the maxillary central incisor (2.93 +- 1.57 mm; p=0.003), lateral incisor (1.87 +- 1.12 mm; p=0.005) and canine (0.59 +- 0.62 mm; p=0.031). With increasing age, the amount of maxillary anterior teeth visible at rest significantly decreased (p < 0.001), and increased for the mandibular teeth (p < 0.001). Subjects with shorter upper lips significantly displayed more maxillary anterior incisor structure than subjects with longer upper lip (p < 0.001). Conclusion: Females displayed significantly more labial length of the maxillary anterior teeth. The mean visible labial length of maxillary anterior teeth significantly decreased with increasing age and increased for the mandibular teeth. As the upper lip length increased, the mean visible labial length of maxillary anterior teeth significantly decreased. (author)

Effect of different composite core materials on fracture resistance of endodontically treated teeth restored with FRC posts.

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Panitiwat, Prapaporn; Salimee, Prarom

2017-01-01

This study evaluated the fracture resistance of endodontically treated teeth restored with fiber reinforced composite posts, using three resin composite core build-up materials, (Clearfil Photo Core (CPC), MultiCore Flow (MCF), and LuxaCore Z-Dual (LCZ)), and a nanohybrid composite, (Tetric N-Ceram (TNC)). Forty endodontically treated lower first premolars were restored with quartz fiber posts (D.T. Light-Post) cemented with resin cement (Panavia F2.0). Samples were randomly divided into four groups (n=10). Each group was built-up with one of the four core materials following its manufacturers' instructions. The teeth were embedded in acrylic resin blocks. Nickel-Chromium crowns were fixed on the specimens with resin cement. The fracture resistance was determined using a universal testing machine with a crosshead speed of 1 mm/min at 1350 to the tooth axis until failure occurred. All core materials used in the study were subjected to test for the flexural modulus according to ISO 4049:2009. One-way ANOVA and Bonferroni multiple comparisons test indicated that the fracture resistance was higher in the groups with CPC and MCF, which presented no statistically significant difference (p>0.05), but was significantly higher than in those with LCZ and TNC (paligned with the same tendency of fracture loads. Among the cores used in this study, the composite core with high filler content tended to enhance fracture thresholds of teeth restored with fiber posts more than others.

Determination of Radionuclide Concentration in Human Teeth in Najaf Governorate, Iraq

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Basim Almayahi

2017-12-01

Full Text Available Introduction: 238U decays with alpha particles emission into 234Th and the series ends with 206Pb. The unstable nucleus loses the energy with emitting ionizing alpha particles for reaching a stable state. It is undergoing alpha decay with decay energy (4.679 MeV. Alpha particles enter the human and animal bodies through inhalation of air or ingestion of contaminated food and water. This study aimed to perform a radiological analysis on the natural alpha particle emission rates of the human teeth as the biomarkers of radiation exposure and environmental pollution. Materials and Methods: This study was conducted on 68 teeth samples of 27 males and 41 females collected from the hospitals distributed across Najaf governorate, including many districts in Iraq. Alpha particle emission rates were measured using CR-39 nuclear track detector. Results: The mean emission rate of alpha particles in the female teeth was 0.0396±0.0070 mBq cm-2, which was relatively higher than that in the male teeth (0.0390±0.0048 mBq cm-2. Nevertheless, there was no significant difference between the female and male teeth regarding the emission rate of alpha particles. Furthermore, the emission rate of alpha particles in the teeth of the samples taken from Kufa (0.0417±0.0057 mBq cm-2 was higher than those obtained from Najaf (0.0384±0.0053 mBq cm-2. Conclusion: As the findings of this study revealed, Najaf governorate had a lower emission rate of alpha particles as compared to other sites of the worldwide. Therefore, it could be concluded that there is no negative consequence threatening the people’s health in this regard.

Creating Esthetic Harmony with Nonloading, Fixed Provisional Restoration using Extracted Teeth after Immediate Implant Placement.

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Satwalekar, Parth; Satwalekar, Tanushree; Bondugula, Vasanthi; Bhuvaneshwari, B; Harshavardhan, K V; Pasula, Kiran

2016-04-01

To make use of fiber-reinforced composite and the patient's own extracted teeth in fabricating a provisional restoration following immediate implant placement. Fiber-reinforced composites offer various possibilities in temporization of osseointegrating implants in the esthetic zone. In this chairside technique, the patient's own extracted teeth with fiber-reinforced composite were used to fabricate a provisional restoration after immediate implant placement. A putty index was made before extracting the teeth and placing the implants as planned. The index and crowns of the extracted teeth were used to make a nonloading, esthetic, chair-side provisional restoration after immediate implant placement. By using the patient's own teeth for pro-visionalization immediately after implant placement, acceptance is greatly enhanced.

NEED OF PREVENTION STEPS AGAINST IMPACTION OF MANDIBULAR AND MAXILLARY PREMOLARS.

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Hristina Arnautska

2015-11-01

Full Text Available Lower second premolars, closely followed by upper premolars, are regarded as the third most common teeth prone to impaction, after wisdom teeth and upper canines. Objective of this article is to show the possibility for spontaneous eruption of impacted premolars upon extraction of deciduous molars and removal of the follicular cyst as described in several clinical cases. The present paper reports four clinical cases supporting the thesis that regardless of the reason behind impacted premolars, undertaking preventive measures significantly improves the position of the germ of those teeth. Conclusions: The early extraction of the deciduous molar, monitoring the patient and reserving the space for the succeeding impacted premolar can lead to non-invasive or relatively short orthodontic treatment (secondary prevention.If root development is incomplete yet there is a good growth potential which could lead to spontaneous eruption (primary prevention. Age specifics particular to children such as the great regenerative abilities of the bone, provide a good prognosis for spontaneous eruption or significant improvement in the position of impacted premolars and facilitate the orthodontic treatment.

Do the levels of selected metals differ significantly between the roots of carious and non-carious teeth?

International Nuclear Information System (INIS)

Malara, Piotr; Kwapulinski, Jerzy; Malara, Beata

2006-01-01

Since the metals deposited in teeth during formation and mineralization processes are to a large extent retained, human teeth receive a considerable attention as the indicators of the heavy metal exposure. The use of permanent teeth is limited because the extraction of healthy permanent teeth just for this purpose is hardly acceptable. As the issue of the loss of elements from a carious lesion in the coronal part of a tooth remains controversial, the valuable material could only be the root of carious and fractured permanent teeth. However, to ensure the validity of the results, it should be ascertained that the levels of certain toxic and essential elements do not differ significantly between the roots of non-carious and carious teeth, and therefore this is the aim of this project. The levels of cadmium, chromium, copper, iron, manganese, lead, zinc, potassium, sodium, calcium and magnesium were determined in the roots of 344 permanent teeth (189 carious and 155 caries-free teeth) from the residents of Ruda Slaska, Poland, aged 18 to 34. No statistically significant difference between the concentration of these metals in the roots of non-carious and carious teeth was found. This finding applies to both the general population and after the grouping by donor's gender and tooth type. The concentration of lead, iron, calcium and manganese in the roots of non-carious and carious teeth exhibited dependence upon tooth type, as well as the concentration of potassium in the roots of carious teeth. Since the mineral composition of the roots of permanent teeth is similar for the non-carious, as well as the carious teeth, they can be indiscriminately selected for the tests required by a research project, as they will produce the comparable results. However, in the case of lead, iron, calcium, potassium and manganese, the comparison should be made after grouping by tooth type

Dental anomalies in primary dentition and their corresponding permanent teeth.

Science.gov (United States)

Gomes, R R; Fonseca, J A C; Paula, L M; Acevedo, A C; Mestrinho, H D

2014-05-01

The objectives of this paper are to estimate the prevalence of dental anomalies in primary dentition in a sample of 2- to 5-year-old Brazilian preschool children, determine their distribution, and investigate their occurrence in the succedaneous teeth of the sample compared with a control group of children with no dental anomalies in the primary dentition. The one-stage sample comprised 1,718 two to five-year-old children with fully erupted primary dentition clinically examined for dental anomalies. All children presenting dental anomalies underwent panoramic radiographs. Descriptive statistics were performed for the studied variables. A control group matched by sex and age was studied to compare the prevalence ratio for dental anomalies in the permanent dentition. The prevalence of dental anomalies in the primary dentition was 1.8 %, with no significant statistical difference between sexes. Double teeth were the most frequently observed. Dental anomalies on the succedaneous permanent teeth were diagnosed in 54.8 % of the children with affected primary dentition. The prevalence ratio (PR) for dental anomalies in the succedaneous permanent teeth was 17.1 (confidence interval (CI) 5.33-54.12) higher compared with the control group, higher in children with bilateral anomalies (PR = 31.2, CI 10.18-94.36). An association between anomalies of the permanent dentition and the presence of dental anomalies in primary teeth was observed, especially when they occur bilaterally. The results in the present study have a clinical relevance in the diagnosis of children with dental anomalies in primary dentition. Early identification of these anomalies can aid the dentist in planning dental treatment at the appropriate time.

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

OpenAIRE

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 supernume...

Relationship between amount of overtime work and untreated decayed teeth in male financial workers in Japan.

Science.gov (United States)

Yoshino, Koichi; Suzuki, Seitaro; Ishizuka, Yoichi; Takayanagi, Atsushi; Sugihara, Naoki; Kamijyo, Hideyuki

2017-05-25

Continuous or frequent overtime work has been shown to have harmful effects on human health. Meanwhile, one of the main reasons for tooth loss is caries. The aim of this study was to assess the relationship between overtime work and untreated decayed teeth in male financial workers. The participants were recruited by applying screening procedures to a pool of Japanese registrants in an online database. Participants filled out a questionnaire about their oral health, behavior, and working conditions. Participants comprised a total of 951 financial male workers, aged 25-64 years. The likelihood of tooth decay increased with amount of overtime work (p=0.002). After adjusting for age, income, educational background, oral hygiene behavior, snacking behavior, regular dental visitation, bad interpersonal relationships at work, and smoking habit, a multiple logistic regression analysis found that participants with 45-80 h of overtime work (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.23-5.33) or over 80 h of overtime work (OR, 3.01; 95% CI, 1.13-7.97) were more likely to have untreated tooth decay. The percentage of participants who gave "too busy with work" as the reason for leaving decayed teeth untreated increased with amount of overtime (p<0.001). These results indicate that overtime work is strongly related to untreated decayed teeth. In addition to oral health education and dental checkups, decreasing stress and decreasing the amount of overtime work may also have a positive effect on oral health in the workplace.

Clinical and radiographic sequelae to primary teeth affected by dental trauma: a 9-year retrospective study

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Vanessa Polina Pereira Costa

Full Text Available Abstract This retrospective study aimed at determining the predicted risks of clinical and radiographic complications in primary teeth following traumatic dental injuries, according to injury type, severity and child’s age. Data were collected from records of children treated at a Dental Trauma Center in Brazil for nine years. Records of 576 children were included; clinical sequelae were assessed in 774 teeth, and radiographic sequelae, in 566 teeth. A total of 408 teeth (52.7% had clinical sequelae and 185 teeth (32.7%, radiographic sequelae. The type of injury with the highest number of clinical sequelae was the crown-root fracture (86.4%. Clinical sequelae increased with injury severity (p < 0.001, whereas radiographic sequelae did not (0.236. The predicted risk of color change was 29.0% (95%CI 19–41 for teeth with enamel fracture, and 26.0% (95%CI 14–40 for teeth with enamel dentin fracture as well as enamel dentin pulp fracture. Risk of periapical radiolucency was higher for teeth with enameldentinpulp fracture (61.1% 95%CI 35–82 and those with subluxation (15.8% 95%CI 10–22. Risk of premature loss was 27.3% (95%CI 13–45 for teeth with extrusive luxation, and 10.2% (95%CI 5–17 for those with intrusive luxation. The assessment of predicted risks of sequelae showed that teeth with hard tissue trauma tended to present color change, periapical radiolucency and premature loss, whereas teeth with supporting tissue trauma showed color change, abnormal position, premature loss and periapical radiolucency as the most common sequelae. Knowledge about the predicted risks of complications may help clinicians establish appropriate treatment plans.

Teeth in the Line of Fracture: To Retain or Remove?

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Samson, Jimson; John, Reena; Jayakumar, Shalini

2010-01-01

The purpose of this study was to analyze mandibular fracture site, relationship of the fracture line to the periodontium, vitality of teeth, displacement of the fracture segments and their implications, and determine whether to retain or remove the teeth in the fracture line. Fifty patients with 62 fractures were involved in this study. An electric pulp tester was used to measure the pulpal response. The degree of fracture displacement and the relationship of the fracture line to the periodontium were evaluated using panoramic radiographs. Fractures of the parasymphysis region constituted a majority of 60.87% in the gross displacement category. Four of 50 patients showed no response presurgically and minimal response postoperatively on pulp vitality testing. Patients with teeth in the fracture line showing no response on pulp vitality testing should be advised extraction to avoid further complications. PMID:22132255

A Novel Marker Based Method to Teeth Alignment in MRI

Science.gov (United States)

Luukinen, Jean-Marc; Aalto, Daniel; Malinen, Jarmo; Niikuni, Naoko; Saunavaara, Jani; Jääsaari, Päivi; Ojalammi, Antti; Parkkola, Riitta; Soukka, Tero; Happonen, Risto-Pekka

2018-04-01

Magnetic resonance imaging (MRI) can precisely capture the anatomy of the vocal tract. However, the crowns of teeth are not visible in standard MRI scans. In this study, a marker-based teeth alignment method is presented and evaluated. Ten patients undergoing orthognathic surgery were enrolled. Supraglottal airways were imaged preoperatively using structural MRI. MRI visible markers were developed, and they were attached to maxillary teeth and corresponding locations on the dental casts. Repeated measurements of intermarker distances in MRI and in a replica model was compared using linear regression analysis. Dental cast MRI and corresponding caliper measurements did not differ significantly. In contrast, the marker locations in vivo differed somewhat from the dental cast measurements likely due to marker placement inaccuracies. The markers were clearly visible in MRI and allowed for dental models to be aligned to head and neck MRI scans.

Prevalence of delayed emergence of permanent teeth as a result of local factors.

Science.gov (United States)

Johnsen, D C

1977-01-01

Delayed emergence of permanent teeth as a result of local etiologic factors was found in 45 of 1,032(4.3%) persons ages 8 through 18 in a dentally indigent population. In 36 persons (3.4%) delayed emergence resulted from causes other than those associated with premature primary molar extraction. This statistic probably approximates the potential for this problem in a treated population group. Teeth most commonly involved were mandibular second premolars, maxillary canines, and maxillary central incisors. The most common causes, respectively, were space loss, palatal position, and mesiodens. Supernumerary, malformed, and congenitally missing teeth were more frequent in persons with delayed emergence than in the rest of the population sampled. The difference was statistically significant. No correlation was found between delayed emergence and sex of the patient. In this study, teeth delayed in emergence behaved as other teeth in that they exhibited normal root development and did not contribute to resorption of adjacent roots. Except for maxillary canines, enlarged follicular spaces did not develop after eruption

PULPAL BLOOD FLOW CHANGES IN ABUTMENT TEETH OF REMOVABLE PARTIAL DENTURES

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Kunt, Göknil Ergün; Kökçü, Deniz; Ceylan, Gözlem; Yılmaz, Nergiz; Güler, Ahmet Umut

2009-01-01

The purpose of this study was to investigate the effect of tooth supported (TSD) and toothtissue supported (TTSD) removable partial denture wearing on pulpal blood flow (PBF) of the abutment teeth by using Laser Doppler Flowmeter (LDF). Measurements were carried out on 60 teeth of 28 patients (28 teeth and 12 patients of TTSD group, 32 teeth and 16 patients of TSD group) who had not worn any type of removable partial dentures before, had no systemic problems and were non smokers. PBF values were recorded by LDF before insertion (day 0) and after insertion of dentures at day 1, day 7 and day 30. Statistical analysis was performed by student t test and covariance analyses of repeated measurements. In the group TTSD, the mean values of PBF decreased statistically significantly at day 1 after insertion when compared with PBF values before insertion (p<0,01). There was no statistically significant difference among PBF mean values on 1st, 7th and 30th day. However, in the group TSD, there was no statistically significant difference among PBF mean values before insertion and on 1st, 7th and 30th day. In other words, PBF mean values in group TSD continued without changing statistically significant on 1st, 7th and 30th day. TTSD wearing may show negative effect on the abutment teeth due to decreasing basal PBF. PMID:20001995

Pulpal blood flow changes in abutment teeth of removable partial dentures

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Göknil Ergün Kunt

2009-11-01

Full Text Available The purpose of this study was to investigate the effect of tooth supported (TSD and toothtissue supported (TTSD removable partial denture wearing on pulpal blood flow (PBF of the abutment teeth by using Laser Doppler Flowmeter (LDF.Measurements were carried out on 60 teeth of 28 patients (28 teeth and 12 patients of TTSD group, 32 teeth and 16 patients of TSD group who had not worn any type of removable partial dentures before, had no systemic problems and were non smokers. PBF values were recorded by LDF before insertion (day 0 and after insertion of dentures at day 1, day 7 and day 30. Statistical analysis was performed by student t test and covariance analyses of repeated measurements.In the group TTSD, the mean values of PBF decreased statistically significantly at day 1 after insertion when compared with PBF values before insertion (p<0,01. There was no statistically significant difference among PBF mean values on 1st, 7th and 30th day. However, in the group TSD, there was no statistically significant difference among PBF mean values before insertion and on 1st, 7th and 30th day. In other words, PBF mean values in group TSD continued without changing statistically significant on 1st, 7th and 30th day.TTSD wearing may show negative effect on the abutment teeth due to decreasing basal PBF.

Surgical treatments of the impacted canine tooth in young dogs

International Nuclear Information System (INIS)

Amimoto, A.; Iwamoto, S.; Hachimura, H.; Sasaki, K.; Taura, Y.; Nakama, S.; Yamanouchi, T.

1993-01-01

Surgical treatments of the impacted canine tooth were carried out in 8 young dogs, and the results were successful in 12 out of 14 cases (85.7%). The treatments consisting of surgical correction by immediate tipping movement, fenestration of the gingiva, and removal of the impacted tooth, were applied to 14 cases radiographically showing the immature tooth root and no abnormalities in the tooth root or alveolar bone. Impacted teeth were seen in 8 regions of the maxilla and 6 regions of the mandible. Mesioversion was seen in almost all maxillary impacted teeth, while linguoversion or lingual mesioversion in all mandibular cases. Surgical correction was carried out by immediate tipping movement after removal of the retained deciduous canine with or without resection of the alveolar bone. Fixation of the moved teeth was done using a wedge made from the deciduous canine root, which was driven into the vacant alveolar cavity after moving. An additional fixation using a steel wire and/or self-curing resin was done, if necessary

Congenital adrenal hyperplasia: a case report with premature teeth exfoliation and bone resorption.

Science.gov (United States)

Angelopoulou, Matina V; Kontogiorgos, Elias; Emmanouil, Dimitris

2015-06-01

Congenital adrenal hyperplasia (CAH) is an inherited autosomal recessive disorder characterized by insufficient production of cortisol. The aim of this case report was to present a child with CAH, premature exfoliation of primary teeth and accelerated eruption of his permanent teeth related to bone resorption. A 4.5-year-old Caucasian boy with CAH and long-term administration of glucocorticoids was referred for dental restoration. Clinical examination revealed primary molars with worn stainless steel crowns, severe attrition of the upper canines, and absence of the upper incisors. Before the completion of treatment, abnormal mobility of the first upper primary molars and the lower incisors was detected, and a few days later the teeth exfoliated prematurely. Histologic examination revealed normal tooth structure. Alkaline phosphatase and blood cells values were normal. Eruption of the permanent dentition was also accelerated. Tooth mobility was noticed in the permanent teeth as soon as they erupted, along with bone destruction. Examination revealed an elevated level of receptor activator of nuclear factor-κB ligand and lower-than-normal osteoprotegerin and vitamin D levels. The patient was treated with vitamin D supplements, and his teeth have been stable ever since. CAH is a serious chronic disorder appearing in children with accelerated dental development and possibly premature loss of primary teeth. Copyright © 2015 by the American Academy of Pediatrics.

Enhanced regeneration potential of mobilized dental pulp stem cells from immature teeth.

Science.gov (United States)

Nakayama, H; Iohara, K; Hayashi, Y; Okuwa, Y; Kurita, K; Nakashima, M

2017-07-01

We have previously demonstrated that dental pulp stem cells (DPSCs) isolated from mature teeth by granulocyte colony-stimulating factor (G-CSF)-induced mobilization method can enhance angiogenesis/vasculogenesis and improve pulp regeneration when compared with colony-derived DPSCs. However, the efficacy of this method in immature teeth with root-formative stage has never been investigated. Therefore, the aim of this study was to examine the stemness, biological characteristics, and regeneration potential in mobilized DPSCs compared with colony-derived DPSCs from immature teeth. Mobilized DPSCs isolated from immature teeth were compared to colony-derived DPSCs using methods including flow cytometry, migration assays, mRNA expression of angiogenic/neurotrophic factor, and induced differentiation assays. They were also compared in trophic effects of the secretome. Regeneration potential was further compared in an ectopic tooth transplantation model. Mobilized DPSCs had higher migration ability and expressed more angiogenic/neurotrophic factors than DPSCs. The mobilized DPSC secretome produced a higher stimulatory effect on migration, immunomodulation, anti-apoptosis, endothelial differentiation, and neurite extension. In addition, vascularization and pulp regeneration potential were higher in mobilized DPSCs than in DPSCs. G-CSF-induced mobilization method enhances regeneration potential of colony-derived DPSCs from immature teeth. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Influence of Different Rotor Teeth Shapes on the Performance of Flux Switching Permanent Magnet Machines Used for Electric Vehicles

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Jing Zhao

2014-12-01

Full Text Available This paper investigated a 12-slot/11-pole flux switching permanent magnet (FSPM machine used for electric vehicles (EVs. Five novel rotor teeth shapes are proposed and researched to reduce the cogging torque and torque ripple of the FSPM machine. These rotor teeth shapes are notched teeth, stepped teeth, eccentric teeth, combination of notched and stepped teeth, and combination of notched and eccentric teeth. They are applied on the rotor and optimized, respectively. The influences of different rotor teeth shapes on cogging torque, torque ripple and electromagnetic torque are analyzed by the 2-D finite-element method (FEM. Then, the performance of FSPMs with different rotor teeth shapes are compared and evaluated comprehensively from the points of view of cogging torque, torque ripple, electromagnetic torque, flux linkage, back electromotive force (EMF, and so on. The results show that the presented rotor teeth shapes, especially the combination of stepped and notched teeth, can greatly reduce the cogging torque and torque ripple with only slight changes in the average electromagnetic torque.

Accuracy of cone-beam computed tomography in predicting the diameter of unerupted teeth.

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Nguyen, Emerald; Boychuk, Darrell; Orellana, Maria

2011-08-01

An accurate prediction of the mesiodistal diameter (MDD) of the erupting permanent teeth is essential in orthodontic diagnosis and treatment planning during the mixed dentition period. Our objective was to test the accuracy and reproducibility of cone-beam computed tomography (CBCT) in predicting the MDD of unerupted teeth. Our secondary objective was to determine the accuracy and reproducibility of 3 viewing methods by using 2 CBCT software programs, InVivoDental (version 4.0; Anatomage, San Jose, Calif) and CBWorks (version 3.0, CyberMed, Seoul, Korea) in measuring the MDD of teeth in models simulating unerupted teeth. CBCT data were collected on the CB MercuRay (Hitachi Medical Corporation, Tokyo, Japan). Models of unerupted teeth (n = 25), created by embedding 25 tooth samples into a polydimethylsiloxane polymer with a similar density to tissues surrounding teeth, were scanned and measured by 2 investigators. Repeated MDD measurements of each sample were made by using 3 CBCT viewing methods: InVivo Section, InVivo Volume Render (both Anatomage), and CBWorks Volume Render (version 3.0, CyberMed). These measurements were then compared with the MDD physically measured by digital calipers before the teeth were embedded and scanned. All 3 of the new methods had mean measurements that were statistically significantly less (P <0.0001) than the physical method, adjusting for investigator and tooth effects. Specifically, InVivo Section measurements were 0.3 mm (95% CI, -0.4 to -0.2) less than the measurements with calipers, InVivo Volume Render measurements were 0.5 mm less (95% CI, -0.6 to -0.4) than those with calipers, and CBWorks Volume Render measurements were 0.4 mm less (95% CI, -0.4 to -0.3) than those with calipers. Overall, there were high correlation values among the 3 viewing methods, indicating that CBCT can be used to measure the MDD of unerupted teeth. The InVivo Section method had the greatest correlation with the calipers. Copyright © 2011 American

Numerical study of impact erosion of multiple solid particle

Science.gov (United States)

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

2017-11-01

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

Evaluating success of autotransplantation of embedded/impacted third molars harvested using piezosurgery: a pilot study.

Science.gov (United States)

Nagori, Shakil Ahmed; Jose, Anson; Bhutia, Ongkila; Roychoudhury, Ajoy

2014-11-01

To evaluate the success of autogenous transplantation of embedded/impacted third molars harvested using piezosurgery. This prospective pilot study enrolled 20 healthy patients with non-restorable first/second molars and a caries-free retrievable embedded/impacted third molar. Piezosurgery was used for removing inter-radicular bone at the recipient socket as well as for bone removal around the donor teeth. After an average follow-up of 16.4 months (SD = 1.9), 18 cases were successful with formation of periodontal ligament around the teeth. One tooth was lost due to infection at 1 month. One patient was lost to follow-up. There was no root resorption or ankylosis in any of the cases. In six donor teeth with complete root formation, root canal treatment was carried out. All the remaining teeth responded positively with vitality testing. Piezosurgery is an effective device if embedded/impacted third molars are to be harvested for successful autogenous transplantation.

Bruxism (Teeth Grinding or Clenching) (For Parents)

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Bruxism (Teeth Grinding or Clenching) KidsHealth / For Parents / Bruxism ( ... called bruxism , which is common in kids. About Bruxism Bruxism is the medical term for the grinding ...

Cleidocranial dysplasia: Report of 4 cases and review

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Virender Gombra

2008-01-01

Full Text Available Patients with cleidocranial dysplasia commonly present with significant dental problems such as retention of multiple deciduous teeth, impaction or delay in eruption of permanent teeth and often, the presence of supernumerary teeth. We report 4 cases of 2 families presenting with cleidocranial dysplasia disorder with their clinical and radiological diagnosis and illustrating its pathogenesis and various treatment modalities, review of literatures.

Trace elements in human, cattle and swine teeth, measured by external beam PIXE-PIGE setup

International Nuclear Information System (INIS)

Tabacniks, M.H.; Rizzutto, M.A.; Added, N.; Liguori Neto, R.; Acquadro, J.C.; Vilela, M.; Oliveira, T.R.C.F.; Markarian, R.A.; Mori, M.

2001-01-01

The use of animal teeth to replace human teeth in dentistry school classes and to test chemicals and fillings, motivated for a better characterization of the elementary composition of their enamel, since some of the chemical properties, adhesion and chemical compatibility may depend on these parameters. Cattle, swine and human teeth were collected by dentists of the University of Sao Paulo. These teeth came primarily from Sao Paulo region and were analyzed for trace elements at the Open Nuclear Physics Laboratory, using a high energy external proton beam, PIXE-PIGE setup

Histobacteriologic Conditions of the Apical Root Canal System and Periapical Tissues in Teeth Associated with Sinus Tracts.

Science.gov (United States)

Ricucci, Domenico; Loghin, Simona; Gonçalves, Lucio S; Rôças, Isabela N; Siqueira, José F

2018-03-01

This histobacteriologic study described the pattern of intraradicular and extraradicular infections in teeth with sinus tracts and chronic apical abscesses. The material comprised biopsy specimens from 24 (8 untreated and 16 treated) roots of teeth associated with apical periodontitis and a sinus tract. Specimens were obtained by periradicular surgery or extraction and were processed for histobacteriologic and histopathologic methods. Bacteria were found in the apical root canal system of all specimens, in the main root canal (22 teeth) and within ramifications (17 teeth). Four cases showed no extraradicular infection. Extraradicular bacteria occurred as a biofilm attached to the outer root surface in 17 teeth (5 untreated and 12 treated teeth), as actinomycotic colonies in 2 lesions, and as planktonic cells in 2 lesions. Extraradicular calculus formation (mineralized biofilm) was evident in 10 teeth. Teeth with chronic apical abscesses and sinus tracts showed a very complex infectious pattern in the apical root canal system and periapical lesion, with a predominance of biofilms. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Improved patient-reported health impact of multiple sclerosis

DEFF Research Database (Denmark)

Macdonell, Richard; Nagels, Guy; Laplaud, David-Axel

2016-01-01

BACKGROUND: Multiple sclerosis (MS) is a debilitating disease that negatively impacts patients' lives. OBJECTIVE: ENABLE assessed the effect of long-term prolonged-release (PR) fampridine (dalfampridine extended release in the United States) treatment on patient-perceived health impact in patients...... with MS with walking impairment. METHODS: ENABLE was a 48-week, open-label, Phase 4 study of PR-fampridine 10 mg twice daily. Patients who showed any improvement in Timed 25-Foot Walk walking speed at weeks 2 and 4 and any improvement in 12-item MS Walking Scale score at week 4 remained on treatment....... The primary endpoint was change from baseline in 36-Item Short-Form Health Survey (SF-36) physical component summary (PCS) score. RESULTS: At week 4, 707/901 (78.5%) patients met the criteria to remain on treatment. Patients on treatment demonstrated significant and clinically meaningful improvements in SF-36...

Full Pulpotomy with Biodentine in Symptomatic Young Permanent Teeth with Carious Exposure.

Science.gov (United States)

Taha, Nessrin A; Abdulkhader, Sakhaa Z

2018-04-19

This prospective study evaluated the outcome of Biodentine (Septodont, Saint Maur des Fosses, France) pulpotomy in young permanent teeth with carious exposure. Twenty permanent molar teeth in 14 patients with carious pulp exposure were treated with Biodentine pulpotomy. The age of the patients ranged from 9-17 years (12.3 ± 2.7 years). A preoperative pulpal and periapical diagnosis was established. After informed consent, the tooth was anesthetized, isolated via a dental dam, and disinfected with 5% sodium hypochlorite before caries excavation. Full pulpotomy was performed by amputating the exposed pulp to the level of the canal orifices, hemostasis was achieved via a cotton pellet moistened with 2.5% sodium hypochlorite, a 3-mm layer of Biodentine was placed as the pulpotomy agent, a Vitrebond liner (3M ESPE, St Paul, MN) was applied, and the tooth was subsequently restored. Postoperative periapical radiographs were taken after placement of the permanent restoration. Clinical and radiographic evaluation was completed after 6 months and 1 year postoperatively. Pain levels were scored preoperatively and 2 days after treatment. Statistical analysis was performed using the Fisher exact test. Clinical signs and symptoms suggestive of irreversible pulpitis were established in all teeth and symptomatic apical periodontitis in 14 of 20 (70%). Two days after treatment, all patients reported complete relief of pain. All teeth were clinically successful at 6 months and 1 year postoperatively. Radiographically, immature roots showed continued root development; dentin bridge formation was detected in 5 of 20 teeth. Seven of 7 teeth with preoperative periapical rarefaction showed signs of healing; 1 tooth had signs of internal root resorption at 1 year with an overall success rate of 95% (19/20). Young permanent teeth with carious exposure can be treated successfully with full pulpotomy using Biodentine, and clinical signs and symptoms of irreversible pulpitis are

Management of anterior teeth damage caused by complex caries through aesthetic endorestoration

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Nanik Zubaidah

2011-03-01

Full Text Available Background: Dental caries is a microbiological disease that result in localized dissolution and destruction of the calcified tissue. It is multifactorial, therefore prevention must be based on a multifactorial approach. The damage of anterior teeth due to complex caries, for certain person may interfere their performance and decrease their self confidence aesthetically. Restoration of tooth form and function, especially on anterior teeth is highly valuable. Purpose: To present a case of maxillary anterior teeth with complex caries, through endorestoration treatment for recovering its original function and aesthetic. Case: The 21 years old male patient with complex carries on maxillary anterior teeth number 12, 11, 21, 22 and 23. The patient felt bad about his performance and affect his self confidence. The patient visited the clinic to repair his teeth and to get its form and function aesthetically. Case management: The endorestoration treatment was performed for carious teeth through pulpectomy followed by insertion of post retention and porcelain fused to metal crowns. Conclusion: Anterior teeth with severed complex caries can be managed through endorestoration treatment to recover its performance and function aesthetically.Latar belakang: Dental karies adalah penyakit infeksi yang berakibat kerusakan jaringan kalsifikasi dan bersifat multifactorial. Oleh karena itu pencegahan dilakukan dengan pendekatan multifactorial. Kerusakan gigi anterior karena karies kompleks untuk orang-orang tertentu mungkin berdampak pada penampilan dan penurunan kepercayaan diri karena factor estetik. Perbaikan gigi anterior dari berbagai kerusakan baik dalam hal bentuk maupun fungsinya sangat besar nilainya. Tujuan: Untuk menunjukkan kasus gigi anterior rahang atas karena karies kompleks melalui perawatan endorestorasi untuk mengembalikan fungsi gigi asli dan estetik. Kasus: Laki-laki usia 21 tahun dengan karies kompleks pada gigi anterior rahang atas 12, 11, 21

[Endodontically treated teeth. Success--failure. Endorestorative treatment plan].

Science.gov (United States)

Zabalegui, B

1990-01-01

More and more often the general dentist is finding the presence of endodontically treated teeth during his treatment planning procedure. He has to ask himself if the endo-treated tooth functions and will continue to function function successfully, when deciding which final endo-restorative procedure to apply. For this reason the dentist or the endodontist with whom he works should clinically evaluate these teeth, establish a diagnostic criteria of their success or failure and a treatment plan according to the prognosis. The purpose of this article is to offer an organized clinical view of the steps to follow when evaluating an endodontically treated tooth and how to establish a final endo-restorative plan.

Teeth and irradiation in head and neck cancer

International Nuclear Information System (INIS)

Thariat, J.; Ortholan, C.; Thariat, J.; Darcourt, V.; Poissonnet, G.; Dassonville, O.; Marcy, P.Y.; Bozec, A.; Ortholan, C.; Santini, J.; Thariat, J.; Mones, E. de; Darcourt, V.; Poissonnet, G.; Dassonville, O.; Bozec, A.; Santini, J.; Savoldelli, C.; Odin, G.; Guevara, N.; Marcy, P.Y.; Bensadoun, R.J.

2010-01-01

Pre-irradiation dental care depends on teeth health, fields and dose of irradiation, compliance to fluorides, cessation of tobacco and psycho-social cofactors. Dental care aims at preventing complications and preserving the quality of life (eating, speech and aesthetics). Approximately 11% of patients do not require any pre-irradiation dental care. Dental complications vary from slight colorations of the teeth to major complication such as osteoradionecrosis. Osteoradionecrosis rates vary from 1 to 9%, and may be decreased by using a 21-day delay between extractions and irradiation, provided that it does not postpone cancer treatment, with a dose-dependent risk ( 60 Gy). Osteoradionecrosis occurs spontaneously (35%), mostly involves the mandible (85%). (authors)

Sr and Nd isotope systematics in fish teeth

International Nuclear Information System (INIS)

Staudigel, H.; Zindler, A.

1985-01-01

High concentrations of Sr and Nd in fish teeth apatite (up to 2000 and 3800 ppm, respectively) make them relatively impervious to diagenetic overprints and allow high-precision analysis of 87 Sr/ 86 Sr and 143 Nd/ 144 Nd of very small amounts of material. 87 Sr/ 86 Sr ratios of 14 Cenozoic samples ( 87 Sr/ 86 Sr stratigraphic dating. A compilation of published 143 Nd/ 144 Nd data from recent Mn-nodules and marine Fe/Mn deposits shows that the North-Central Pacific Ocean and the major portion of the Atlantic Ocean display distinctly different, narrow ranges in isotopic compositions. Between these two areas, the 143 Nd/ 144 Nd of Mn-nodules vary systematically towards intermediate compositions in the Southern Oceans, reflecting the communication between the Atlantic and Pacific Oceans through the eastward moving Antarctic Circumpolar Current. The 143 Nd/ 144 Nd of the 2-55 Ma old fish teeth analyzed are typically close to the range of 143 Nd/ 144 Nd in Recent Mn-nodules and seawater for the respective ocean and, thus, indicate no significant change through this time period. The 143 Nd/ 144 Nd of fish teeth from the North Pacific Ocean are highest during periods of high aeolian sedimentation. (orig.)

Accounting for multiple sources of uncertainty in impact assessments: The example of the BRACE study

Science.gov (United States)

O'Neill, B. C.

2015-12-01

Assessing climate change impacts often requires the use of multiple scenarios, types of models, and data sources, leading to a large number of potential sources of uncertainty. For example, a single study might require a choice of a forcing scenario, climate model, bias correction and/or downscaling method, societal development scenario, model (typically several) for quantifying elements of societal development such as economic and population growth, biophysical model (such as for crop yields or hydrology), and societal impact model (e.g. economic or health model). Some sources of uncertainty are reduced or eliminated by the framing of the question. For example, it may be useful to ask what an impact outcome would be conditional on a given societal development pathway, forcing scenario, or policy. However many sources of uncertainty remain, and it is rare for all or even most of these sources to be accounted for. I use the example of a recent integrated project on the Benefits of Reduced Anthropogenic Climate changE (BRACE) to explore useful approaches to uncertainty across multiple components of an impact assessment. BRACE comprises 23 papers that assess the differences in impacts between two alternative climate futures: those associated with Representative Concentration Pathways (RCPs) 4.5 and 8.5. It quantifies difference in impacts in terms of extreme events, health, agriculture, tropical cyclones, and sea level rise. Methodologically, it includes climate modeling, statistical analysis, integrated assessment modeling, and sector-specific impact modeling. It employs alternative scenarios of both radiative forcing and societal development, but generally uses a single climate model (CESM), partially accounting for climate uncertainty by drawing heavily on large initial condition ensembles. Strengths and weaknesses of the approach to uncertainty in BRACE are assessed. Options under consideration for improving the approach include the use of perturbed physics

[Heat-induced symptomatology in human teeth. An in-vitro study].

Science.gov (United States)