Ten reasons to not ignore the third molar

ABSTRACT Introduction: The third molars are forgotten because they are the last in the dental arch, they do not directly influence the smile and they appear only in adolescence, when they do. Objectives: 1) to provide the clinician with a "checklist" to assess and diagnose changes to be screened in the third molar region in new patients; 2) to reveal the importance of not discharging the patient submitted to any dental treatment without first analyzing the third molars region clinically and on imaging examinations, since many diseases are associated to them. Result: A list of 10 situations that cover all diagnostic possibilities involving the third molars is presented. Conclusion: Adopting this protocol is a matter of habit, since the need is fundamental. The next professional assisting your patient may ask: "Did he not request examinations for the third molars?".

RESUMO Introdução: Os terceiros molares são esquecidos por serem os últimos dentes na arcada dentária, por não influenciarem diretamente no sorriso e por aparecerem apenas na adolescência - quando aparecem. Objetivos: 1) Fornecer ao clínico um checklist de conferência e diagnóstico de alterações a serem checadas na região dos terceiros molares em novos pacientes; e 2) Destacar a importância de não dar alta ao paciente submetido a qualquer tratamento odontológico sem antes analisar, clínica e imagiologicamente, a região dos terceiros molares, pois muitas doenças estão a eles associadas. Resultado: Criou-se uma lista de 10 situações que englobam todas as possibilidades diagnósticas envolvendo os terceiros molares. Conclusão: Adotar esse protocolo é uma questão de hábito, pois a necessidade é imperiosa. O próximo profissional a atender o seu paciente vai perguntar: "Ele não solicitou exames para os terceiros molares?".

Impacted teeth: Their place is in the dental arch

ABSTRACT The starting point for the treatment of unerupted teeth should consider the fact that, biologically, the pericoronal follicle maintains the ability to release EGF and other mediators responsible for eruption over time. The eruptive events may be guided and directed, so that teeth may occupy the space prepared to receive them in the dental arch, as showed in the case presented to evidence the following principle to be considered in these cases: "Regardless of the position of an unerupted tooth, it may be biologically directed to its place in the dental arch. The orthodontist should apply a mechanics to guide it and park it at its site."

RESUMO Os dentes não irrompidos devem ter como ponto de partida, para seu tratamento, o fato de que biologicamente o folículo pericoronário mantém ao longo do tempo a capacidade de liberar o EGF e outros mediadores responsáveis pela erupção. Pode-se guiar e direcionar os eventos eruptivos para que os dentes ocupem o seu espaço preparado para recebê-los na arcada dentária, como revela o caso apresentado para sedimentar o seguinte princípio a ser considerado para esses casos: "Independentemente da posição que um dente não irrompido se apresente, há como, biologicamente, direcioná-lo para o seu local na arcada dentária. Cabe ao ortodontista aplicar uma mecânica que o leve até o local e lá o estacione."

A mixed radiopaque – radiolucent lesion in the anterior mandible associated with multiple impacted teeth: A radiodiagnostic challenge?

Desmoplastic ameloblastoma (DA) exhibits important differences in gender, anatomic distribution, radiographic findings, and histologic appearance compared to other types of ameloblastoma. Radiologically, DA is seen either as ill-defined mass containing osteolytic and sclerotic areas or as multifocal radiodense flecks within radiolucent background resembling a honeycomb. The radiographic differential diagnosis includes fibro-osseous lesions such as cemento-ossifying fibroma, fibrous dysplasia, calcifying odontogenic cyst, and chronic sclerosing osteomyelitis. Thus, DA should primarily be included in the differential diagnosis of a mixed radiopaque-radiolucent lesion with diffuse borders in the anterior premolar region of the jaws. This report adds to the literature of mixed radiolucent-radiopaque lesions which may not always be histopathologically diagnosed as a fibro-osseous lesion but could turn out to be a DA. This report also benefits the dental community by cautioning them to be aware of DA that can be associated with multiple unerupted teeth which is quite a rare finding.

Why canines induce resorption of neighboring roots? An imaging correlation

ABSTRACT Despite the explanations about the mechanisms and reasons why dental follicles of unerupted maxillary canines do not cause root resorption in neighboring teeth, questions remain about the time expected for this event and the lack of protocols for preventive clinical management, which may serve as insights for further studies. Here, these mechanisms are correlated with imaging findings of CT scans and 3D reconstructions of a typical clinical case.

RESUMO Apesar das explicações dos mecanismos e dos porquês os folículos pericoronários dos caninos superiores não irrompidos podem reabsorver as raízes dos dentes vizinhos, questiona-se a inexistência de previsibilidade do tempo em que isso ocorre e a ausência de protocolos de condutas clínicas preventivas, como insights para novas pesquisas. Correlaciona-se, também, esses mecanismos com os aspectos imaginológicos de cortes tomográficos e reconstruções 3D de um caso clínico característico.

"Maxillary lateral incisor partial anodontia sequence": a clinical entity with epigenetic origin

ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a "syndrome". Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called "Maxillary Lateral Incisor Partial Anodontia Sequence."

RESUMO A relação entre a anodontia parcial do incisivo lateral e o deslocamento palatino do canino superior não irrompido não pode ser considerada uma anomalia dentária múltipla com etiopatogenia genética definida, a ponto de ser considerada como uma "síndrome". Os genes envolvidos sequer foram identificados e localizados no genoma humano, e nem mesmo presumiu-se em qual cromossomo se localizaria o gene responsável. O deslocamento palatino do canino superior em casos de anodontia parcial do incisivo lateral superior está potencialmente associado às mudanças ambientais provocadas pela sua ausência no local de formação e erupção, o que caracterizaria uma etiologia epigenética para essa associação. A falta do incisivo lateral superior na região canina implica em tirar um dos guias referenciais da trajetória eruptiva do canino superior, que ficaria, assim, não irrompido e/ou impactado no palato. Como consequência, e em sequência, promove-se uma má oclusão, atresia maxilar, transposição, retenção prolongada do canino decíduo e reabsorções nos dentes vizinhos. Dessa forma, pode-se afirmar que estamos frente a um conjunto de anomalias e alterações múltiplas sequenciais conhecido como anomalias de desenvolvimento sequencial ou, simplesmente, sequência. Uma vez aceita a condição epigenética e sequencial para esse quadro clínico, ele poderia ser chamado de "Sequência da Anodontia Parcial do Incisivo Lateral Superior".

Evaluación de la exactitud de métodos de Tanaka-Johnston y Moyers en pacientes chilenos del Postgrado de Ortodoncia UNAB Santiago, Chile

Objetivo: Determinar la exactitud del Índice de Tanaka-Johnston e Índice de Moyers mediante el análisis de modelos de estudio iniciales con dentición definitiva de pacientes chilenos del Postgrado de Ortodoncia de la Universidad Andrés Bello sede Santiago. Materiales y métodos: Se seleccionaron por conveniencia 100 pares de modelos según los criterios de inclusión y exclusión establecidos, correspondientes 50 al género femenino y 50 al masculino, y se realizó medición directa con un pie de metro manual, de la suma incisiva inferior y suma de segmentos canino-premolar. La medición fue realizada por dos examinadores previamente calibrados. Se determinó la exactitud de cada uno de los métodos y presencia de diferencias estadísticas significativas. Resultados: Para mujeres, Moyers 65% en maxilar superior y Moyers 50% en maxilar inferior presentan mayor exactitud en predicción de tamaño mesiodistal de caninos y premolares permanentes no erupcionados; en cambio, para hombres, Moyers 75% en maxilar superior y Moyers 65% en maxilar inferior son más exactos. El método de Tanaka-Johnston a pesar que solo presenta diferencias estadísticamente significativas en maxilar inferior en el género femenino (p<0,05), es menos exacto tendiendo a sobrestimar valores reales en mujeres, y a subestimar en hombres. Conclusión: Método de Moyers es más exacto en la predicción del espacio necesario en pacientes chilenos, su nivel de confianza varía según género y maxilar. Diferencias son explicadas por dimorfismo sexual y variaciones étnicas con respecto a la población de origen de métodos de predicción.

Objetive: Determine the accuracy of Tanaka-Johnston and Moyers indexes through the initial analysis of study models with permanent teeth of Chilean patients of the Graduate School Orthodontics of University Andres Bello in Santiago. Materials and Methods: 100 pairs of models were selected by convenience as the inclusion and exclusion criteria established, corresponding to 50 female and 50 male. Direct measurement was performed with a manual caliper gauge by two examiners previously calibrated. The sum of permanent mandibular incisors and sum of segments canine-premolar were measured. The accuracy of each of the present methods and statistical differences were determined. Results: In females, the prediction of width of unerupted canines and premolars is more accurate on maxilla with Moyers 65% and mandible with Moyers 50%. For males, Moyers 75% on maxilla and Moyers 65% in mandible are more accurate. Tanaka-Johnston method although only presented statistically significant differences in mandible of female gender (p <0.05), is less accurate tending to overestimate actual values in women as in men underestimated. Conclusion: Moyers method is more accurate in predicting space required in Chilean patients, the confidence level varies according to gender and jaw. Differences are explained by sexual dimorphism and ethnic variations from the source population of prediction methods.

Radiographic analysis and prevalence of impacted maxillary canine teeth in children between 8 and 16 years / Análisis radiográfico y prevalencia de caninos maxilares retenidos en niños entre 8 y 16 años

The objective of this study was to determine the prevalence of impacted maxillary canines and analyze variables associated with its retention in panoramic radiographs. Manual and Retrospective observational study of 16,835 records. A sample of 1,353 panoramic radiographs was obtained. The variables measured were canine angle, distance from the canine apex to occlusal plane, vertical and horizontal canine location. For reliable measurement an intra class Fleiss and Cohen correlation coefficient was used (0.997). Prevalence was 2.3%. 31 subjects had one or both retained canines. Average age 10.77±2.45, 61.3% were women. 64.5% presented unilateral retaining of which the largest percentage was left. A total of 41 retained canines were observed. Distance to occlusal plane 19 mm on average. In relation to the vertical location the highest percentage (48.7%) was found in the apical third. Regarding the horizontal location the highest percentage (77.6%) was found in sectors 1, 2 and 3. When analyzing the canine angle it was found that 83% measured 31 degrees or more. Radicular resorption was observed in 2 lateral incisors. The prevalence found is similar to that reported in the international literature. It occurred more frequently in women and left unilateral both not statistically significant.

El objetivo de este trabajo fue determinar la prevalencia de dientes caninos maxilares retenidos y analizar variables asociadas a su retención, en radiografías panorámicas. Se realizó un estudio observacional retrospectivo y manual de 16.835 fichas. Se obtuvo una muestra de 1.353 radiografías panorámicas. Las variables medidas fueron ángulo del canino, distancia de la cúspide del canino al plano oclusal, localización vertical y horizontal del canino. Para la fiabilidad de las mediciones se usó el coeficiente de correlación intraclase de Fleiss & Cohen (0,997). La prevalencia fue 2,3%. Treinta y un sujetos presentaron 1 o ambos caninos retenidos. La edad promedio fue 10,77±2,45, y el 61,3% fueron mujeres. El 64,5% presentó retención unilateral, principalmente del lado izquierdo. Se observó un total de 41 caninos retenidos. La distancia al plano oclusal en promedio fue 19 mm. En relación a la localización vertical, el mayor porcentaje (48,7%) se encontró en el tercio apical. Respecto a la localización horizontal, el mayor porcentaje (77,6%) se encontró en los sectores 1, 2 y 3. Al analizar el ángulo canino, se encontró que 83% midió 31 o más. Se observó reabsorción radicular de dos incisivos laterales. La prevalencia encontrada es similar a la reportada en la literatura internacional. La retención se presentó con mayor frecuencia en mujeres y de manera unilateral en el lado izquierdo, pero en ambos casos no es significativa.

Multiple supernumerary teeth in a child with Rubinstein-Taybi syndrome: a rare feature

Rubinstein-Taybi syndrome is a multiple anomalies congenital disorder characterised by broad thumb and halluces, facial dysmorphism with mental and growth retardation. Oral features include small mouth, retro and micronagthic jaws, highly arched and narrow palate. Dental anomalies such as teeth with talon cusps and screwdriver shaped permanent incisors together with crowded teeth are common features in these patients. Although hyperdontia is said to be one of the features of this condition, nevertheless, presence of multiple supernumerary teeth has never been documented. This report highlighted a case of an eleven-year-old boy with Rubinstein-Taybi syndrome referred for unerupted permanent incisors who exhibited multiple supernumerary teeth radiographically.

Cleidocranial dysostosis: a case report / Disostosis cleidocraneal: reporte de caso

Cleidocranial dysostosis is a congenital condition that results from faulty development of membranous bones, mainly the clavicles and skull. The clavicular abnormality may range from a small defect in one clavicle to complete absence of both, but most frequently an absence of the central clavicular segment, as was seen in our patient. A review of the literature has revealed only one previous report a cleidocranial dysostosis syndrome...

La disostosis cleidocraneal es una condición congénita que resulta de un desarrollo defectuoso de los huesos con osificación membranosa, principalmente las clavículas y el cráneo. La anormalidad clavicular puede ir desde un pequeño defecto en una clavícula hasta la total ausencia de ambas, pero con mayor frecuencia se observa la ausencia del segmento clavicular central, como se observó en nuestro paciente. Una revisión de la literatura reveló sólo un caso previo con un síndrome de disostosis cleidocraneal de características similares...