The Ekman-Westborg-Julin syndrome: report of case.
The Ekman-Westborg-Julin Syndrome is reveiwed and a new case reported.
Adolescent↗
SEARCH · Search PubMed
Results for “Tooth Crown”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Regional odontodysplasia. Report of two cases.
Two cases of regional odontodysplasia in girls are reported; one affected the lower incisors, and the other the left maxilla. The first case was radiographically followed over a 6-year period, during which time the ghost teeth exhibited significant dentin formation, along with a resultant decrease in pulp size and relative normalization of the radicular anatomy. The second case involved the deciduous molars and the first permanent molar. In addition to tooth alterations, both cases exhibited many odontogenic epithelial islands and extensive areas of calcification in the mucosa. Diagnosis, causes, and treatment are discussed in the light of recent data.
Adolescent↗
Labial and palatal "talon cusps" on the same tooth: A case report.
Talon cusps are uncommon. Although they normally occur on the palatal surface of maxillary incisors, the literature contains two case reports of labial talon cusps. This is the first report describing a tooth with both a labial and a palatal talon cusp and its successful management.
Child↗
Intracoronal radiolucency in an incompletely erupted permanent molar with a diagnosis of pericoronitis: importance of radiographic examination.
Because of clinical signs and symptoms, a diagnosis of pericoronitis in a partially erupted, partially impacted first molar was made. A more thorough diagnosis was made with the help of a periapical radiograph that showed caries and thus revealed an irreversible pulpitis. Appropriate treatment was the result.
Child↗
Coronectomy (intentional partial odontectomy of lower third molars).
OBJECTIVE: This study evaluates the rate of infection of retained lower third molar roots after coronectomy in teeth judged to be in intimate relation to the inferior alveolar nerve. STUDY DESIGN: This was a retrospective study of 52 patients who were operated on over a 10-year period. RESULTS: Only 3 of 52 patients had to have roots removed because of pain or infection. Postoperative findings and aspects of the surgical technique are also discussed. CONCLUSIONS: Coronectomy is a worthwhile option to extraction where a lower third molar is judged to be in close proximity to the inferior alveolar nerve. In lower third molar removal the potential damage is high when certain radiographic signs are present, whereas the infection rate of roots remaining after coronectomy is, by contrast, low.
Adult↗
Numerical study of porosity in titanium dental castings.
A commercial software package, MAGMASOFT (MAGMA Giessereitechnologie GmbH, Aachen, Germany), was used to study shrinkage and gas porosity in titanium dental castings. A geometrical model for two simplified tooth crowns connected by a connector bar was created. Both mold filling and solidification of this casting model were numerically simulated. Shrinkage porosity was quantitatively predicted by means of a built-in feeding criterion. The risk of gas pore formation was investigated using the numerical filling and solidification results. The results of the numerical simulations were compared with experiments, which were carried out on a centrifugal casting machine with an investment block mold. The block mold was made of SiO2 based slurry with a 1 mm thick Zr2 face coat to reduce metal-mold reactions. Both melting and casting were carried out under protective argon (40 kPa). The finished castings were sectioned and the shrinkage porosity determined. The experimentally determined shrinkage porosity coincided with the predicted numerical simulation results. No apparent gas porosity was found in these model castings. Several running and gating systems for the above model casting were numerically simulated. An optimized running and gating system design was then experimentally cast, which resulted in porosity-free castings.
Journal Article↗
Microbial composition of supra- and subgingival plaque in subjects with adult periodontitis.
BACKGROUND, AIMS: The purpose of the present study was to compare and relate the microbial composition of supra and subgingival plaque in 23 adult periodontitis subjects (mean age 51 +/- 14 years). METHODS: A total of 1,170 samples of supra and subgingival plaque were collected from the mesial aspect of every tooth (up to 28 supra and 28 subgingival samples) from each subject and evaluated for the presence and levels of 40 bacterial taxa using whole genomic DNA probes and checkerboard DNA-DNA hybridization. Clinical assessments including dichotomous measures of gingival redness, bleeding on probing, plaque accumulation and suppuration, as well as duplicate measures of pocket depth and attachment level, were made at 6 sites per tooth. The counts (levels), % DNA probe count (proportion) and % of sites colonized (prevalence) of each species in supra and separately in subgingival plaque were computed for each subject. Significance of differences between supra and subgingival plaque for each species was sought using the Wilcoxon signed ranks test and adjusted for multiple comparisons. RESULTS: All 40 taxa were detected in both supra and subgingival plaque. Actinomyces species were the most prevalent taxa in both habitats. 75 to 100% of supra and 62 to 100% of subgingival sites were colonized by at least one of the 5 Actinomyces species. Supragingival samples exhibited significantly higher counts of Actinomyces naeslundii genospecies 1, Actinomyces israelii, Actinomyces odontolyticus, Neisseria mucosa, Streptococcus gordonii, Capnocytophaga ochracea and Capnocytophaga sputigena when compared with mean counts in subgingival samples taken from the same tooth surfaces. Subgingival plaque samples presented significantly higher counts of Prevotella nigrescens, Prevotella intermedia, Bacteroides forsythus and Porphykromonas gingivalis. Subgingival samples exhibited a significantly higher proportion of "red" and "orange complex" species, while supragingival plaque exhibited higher proportions of "green" and "purple" complex species as well as Actinomyces species. Suspected periodontal pathogens could be detected in supragingival plaque from sites where subgingival samples were negative for the same species. CONCLUSIONS: The data indicate that supragingival plaque can harbor putative periodontal pathogens, suggesting a possible rôle of this environment as a reservoir of such species for the spread or reinfection of subgingival sites.
Actinomyces↗
Incidence rates for complete cusp fracture.
OBJECTIVES: Although complete cusp fracture is acknowledged to occur frequently, incidence rates have been reported rarely. This study determined incidence rates for complete coronal cusp fracture per person and per tooth type. METHODS: All fractures presenting among enrollees in a dental health maintenance organization using two geographically isolated clinics were noted for 105 days. For a sample of these enrollees, likelihood of attending the clinic in the event of a fracture was assessed through a telephone survey, and the at-risk status of all teeth was determined through a record survey. Incidence rates were calculated for persons, and for individual tooth types for all complete fractures and for non-carious complete fractures. In addition, for posterior teeth the distribution of fractured cusps, and the severity of fractures were examined. RESULTS: Per-person incidence rates for complete coronal fractures for all teeth were 89.0 and 72.7 per 1000 person years, respectively, for all fractures and for non-carious fractures. The rates for all anterior and all posterior teeth were 10.2 and 69.9, respectively, for all non-carious fractures. In mandibular posterior teeth, lingual cusps fractured twice as frequently as facial cusps, while the opposite was true for maxillary premolars. Among maxillary molars, the mesiofacial and distolingual cusps fractured most frequently. The large majority of fractures exposed dentin (95%), while pulpal exposure occurred infrequently (3%). A minority of fractures extended below the gingival crest (24%) or the DEJ (25%). CONCLUSIONS: This is the first report of fracture incidence rates for enumerated persons and teeth at risk and as such helps define the magnitude of the problem for dentists and their patients.
Adolescent↗
Classification of dental caries patterns in the primary dentition: a multidimensional scaling analysis.
OBJECTIVE: Clinical patterns of early childhood caries (ECC) encompassing specific teeth or surfaces have been previously proposed on an a priori basis and have been used as case definitions. The underlying assumption is that the patterns result from different host response and environmental conditions. Identifying caries patterns has utility in refining case definitions of ECC. Well-defined caries patterns should enhance the ability of an analysis to identify meaningful associations between suspected risk factors and ECC. The purpose of this project was to identify patterns of caries in the dentition of preschool children using multidimensional scaling without a priori pattern delineation. METHODS: Between February 1994 and September 1995, five examiners visually examined 5171 Arizona preschool children aged 5-59 months old. Multidimensional scaling (MDS) was used as a classification/taxonomy technique to identify any underlying structure of the caries data. MDS provided a classification scheme for individual tooth surfaces based on the dissimilarity measures of squared Euclidean distance and of variance using an alscal analysis. Both two- and three-dimensional solutions were pursued; s-stress, stress, R-square and residual patterns were assessed in determining the best dimensional model, with the resulting quadrant positions of the tooth surfaces suggesting potential caries patterns. RESULTS: All models demonstrated excellent fit. Two- and three-dimensional solutions suggested four caries patterns: (i) any maxillary incisor surfaces, (ii) first molar occlusal surfaces, (iii) second molar pit and fissure surfaces, and (iv) any smooth surfaces, excluding the maxillary incisor surfaces. CONCLUSIONS: This is the first delineation of primary dentition caries patterns produced by a classification analysis without a priori pattern definitions. The identified caries patterns may arise from specific risk factors and/or be a function of the timing of various risk factor exposures. Use of these patterns as case definitions should enhance the ability to identify associations between suspected risk factors and ECC.
Child, Preschool↗
Prediction of mesiodistal canine and premolar tooth width in a sample of Peruvian adolescents.
OBJECTIVES: To compare the predicted tooth width measurements of permanent canine and premolars from Tanaka-Johnston regression equations and Moyers probability tables with the in situ measurements in a sample of Peruvian adolescents. DESIGN: Cross-sectional. SETTING AND SAMPLE POPULATION: Trujillo, Peru; 248 dental casts were measured using a sliding caliper with a Vernier scale rounded to 0.1 mm. RESULTS: Tanaka-Johnston regression equations were not precise, except for the upper arch in the male sample. For females, the Moyers 95th percentile in the upper arch and the 65th percentile in the lower arch predicted the sum precisely. For males, the Moyers 65th percentile for the lower arch predicted the sum precisely, but none of the Moyers percentiles provided precise prediction in the upper arch. CONCLUSIONS: Using tooth width prediction methods from a different racial origin could create an under- or overestimation of the actual combined canine and premolar tooth width, although their clinical significance is disputable.
Adolescent↗
Development of the dentition: four-dimensional visualization and open questions concerning the morphogenesis of tooth form and occlusion.
OBJECTIVES: The formation of the dental primordial should be visualized with special reference to characteristic differences for each single primordium. Until today, it has not been clear how traffic of the ameloblasts is controlled, how the folding pattern of the occlusal relief is generated or how the enamel production is terminated at the enamel surface. DESIGN: Using computer-aided reconstructions from histological serial sections, the dental primordial were visualized and, using fractured enamel specimens, the traces of each single ameloblast were followed by means of scanning electron microscopy. In this way, the developmental movements of the inner enamel epithelium can be reconstructed. RESULTS: Gathering morphological knowledge, three-dimensional polygon sets of shape data were input into a computer workstation and animated by means of the software Soft Image (Microsoft). CONCLUSIONS: The development of the human primary and permanent dentition was animated to simulate growth.
Ameloblasts↗
A comparison of the erosive potential of different beverages in primary and permanent teeth using an in vitro model.
The aim of this study was to compare the erosive potential of different beverages and foodstuffs in primary and permanent teeth. Sixty primary and 60 permanent human teeth were immersed for 3 min in the solution under study (5 teeth per treatment group). Surface microhardness was measured before and after exposure. Initial (baseline) surface microhardness was lower for primary teeth than for permanent teeth. In both primary and permanent teeth, Sprite showed the highest decrease in surface microhardness, whereas yogurt showed an increase in surface microhardness in the primary teeth. Overall decrease was 27.2 +/- 17.5 KHN (mean +/- SD) for primary and 25.9 +/- 15.6 KHN for permanent teeth. The comparison of the erosive susceptibility in this in vitro model showed that primary teeth were not more susceptible to erosion compared to permanent teeth.
Beverages↗
Characteristics of tooth wear in relation to different nutritional patterns including contemporary and medieval subjects.
The present study sought to evaluate the characteristics of tooth wear in subjects with an acidic diet in relation to subjects with substantially different nutritional patterns. The evaluation included medieval skulls (group 1, n = 102, abrasive nutrition), study models of individuals living on an acidic diet (group 2, n = 100) and randomly selected subjects (group 3, n = 100, average Western diet). Wear was visually recorded on oral, vestibular and occlusal/incisal surfaces using quantitative and morphological criteria. The mean age was 42.3 +/- 15.3 yr in group 1, 40.9 +/- 11.2 yr in group 2 and 36.7 +/- 11.7 yr in group 3. Group 1 exhibited the most pronounced substance loss, followed by groups 2 and 3. On occlusal surfaces, cupping was common in group 1 followed by group 2, but was rare in group 3. An inverse relation was found for facets. On buccal surfaces, no substance loss was observed in group 1, whereas in group 2, 63% had at least one tooth with a buccal lesion compared to 8% in group 3. The occlusal substance loss observed in subjects exposed to acids may be interpreted as increased abrasion/demastication of acid-softened dental hard tissues. The occurrence of concavities on smooth surfaces appears to be significant for the diagnosis of dental erosion.
Acids↗
Impact strength of teeth restored by fragment-bonding.
The objective of this in vitro study was to investigate the impact strength of anterior teeth that have been fractured and restored by bonding with a dentin-bonding agent and a composite resin. Twenty sheep central incisors were divided into two groups, 10 in each. One group (intact teeth) served as the control and the teeth in the other group were fractured and then bonded with a bonding agent and a low-viscous composite resin. The specimens were tested in a modified impact-testing machine (pendulum type). The mean impact strength of the intact teeth was 30.6 +/- 2.16 KJ/m2 and of the bonded teeth was 30.2 +/- 1.86 KJ/m2. Statistics revealed that the two means were not significantly different. The results related well with the fracture strength obtained by loading intact and bonded teeth at constant but low speed until fracture. It was concluded that bonding fragments to the remaining tooth structure may restore the tooth to its original strength, measured at modest velocities of the applied force. In other words, reattaching the original coronal fragment of traumatised fractured anterior teeth restored with One-Step dentin bonding system and AEliteflo composite resin would withstand a second trauma to the same extent as intact teeth.
Acid Etching, Dental↗
Urinary catecholamine levels and incidence of dentofacial injuries in children: a 2-year prospective study.
Urinary catecholamines have been used to measure emotionally stressful states which may have an impact on dentofacial injuries. This prospective study investigated the hypothesis that urinary catecholamines such as epinephrine, norepinephrine and dopamine do not affect significantly the incidence of dentofacial injuries in children. As a test of this hypothesis 204 children, males and females, aged 8 to 10 years, were included in the study. After a first examination, each subject was re-examined, at one-year intervals, over a period of two years. Dentofacial injuries were recorded by a clinical examination and a questionnaire. Three 24-h urine samples, with an interval of one year between each, were collected and analyzed by the high performance liquid chromatography technique to assay the catecholamine content. Socio-economic factors were recorded by a questionnaire. Using the panel of data collected, the logistic multiple regression model was employed to test whether the incidence of dentofacial injuries was affected by the studied variables. The 95% probability level was used. Specificity and sensitivity as well as the positive and negative predictive rates were computed. The results showed that epinephrine had a significant correlation with the incidence of dentofacial injuries. Other factors found to have a significant impact were child's age and gender. The values of sensitivity and specificity were 81% and 69% respectively, while the positive and negative predictive rates were 68% and 82% respectively. The data, therefore, provided evidence that emotionally stressful states measured by the urinary catecholamines were prominent etiologic factors of dentofacial injury.
Accidents↗
Prevalence of teeth with untreated dental trauma among nursery and primary school pupils in Dar es Salaam, Tanzania.
The aim of this study was to investigate the prevalence of teeth with untreated dental trauma among children aged 4-15 years in Dar es Salaam, Tanzania. A sample of 4524 children from three districts of different socio-economic status in the Dar es Salaam area was examined for signs of dental trauma in 1998/99. In 21% of all children examined, at least one type of untreated dental trauma was observed. A high percentage of untreated dental trauma was observed at the ages of 4 and 15 years. The most frequently observed type of dental trauma was enamel fracture (67%) followed by enamel-dentin fracture (26%). A significant gender influence on the occurrence of untreated dental trauma was observed, with more boys (23%) having untreated dental trauma than girls (19%). A higher percentage of untreated dental traumas was observed among children in the district with highest SES (26%) compared to the prevalence in the other two districts (14-17%). The findings of this study show that dental traumas are prevalent among Tanzanian children. Therefore, provision of information to the lay community about the importance of early management of dental trauma, ways of preventing trauma and appropriate handling of avulsed teeth is essential in order to minimize the rate of dental injuries and the related complications.
Adolescent↗
Guidelines for the evaluation and management of traumatic dental injuries.
Explore the source record for details and available documents.
Alveolar Process↗
Traumatized primary teeth in children assisted at the Federal University of Santa Catarina, Brazil.
The goal of the present study was to identify the factors related to the occurrence of dental trauma in deciduous teeth. Over a period of 25 months, 85 children between 10 months and 6 years of age were assisted by the staff of the Pediatric Dentistry Clinic of the Federal University of Santa Catarina (UFSC) Florianópolis, Brazil. The children, all assisted by only one professional, a dentist working as a trainee in the Pediatric Dentistry Clinic, had 157 traumatized teeth treated. The occurrence of trauma was higher in male patients (51.8%) and in children between 1 and 3 years old. The average age was about =2.7 years. The 54.1% of the assisted children had more than one traumatized tooth and the repeat trauma occurred 16.7% of the time. Anterior teeth represented 98.7% of the cases and 76.4% of the trauma were on the maxillary central incisor teeth. Both sides of the mouth had approximately the same number of traumatic injuries. Luxations were more frequent (85.4%) than fractures (14.6%). Subluxations represented 38.8% of the luxated teeth. Falls were the main cause of trauma (78%). A percentage of 41.9 children were assisted by a dental professional during the first 24h after the incident. The study concluded that the deciduous dentition is mostly affected by luxations (subluxations) that occur specially on the maxillary central incisor teeth, in patients between 1 and 3 years of age. Falls are the most common etiological factor and more than one traumatized tooth is common. Some of the cases were repeat traumatic injuries.
Accidental Falls↗