Morfología radicular de los terceros molares / Root canal morphology of third molars

Introducción: la morfología radicular es una característica del tercermolar que puede incrementar el grado de difi cultad de la odontectomía,lo que hace necesario indagar sobre sus aspectos anatómicos más frecuentes. Objetivo: Conocer la morfología radicular de los terceros molares. Material y métodos: Se valoraron 155 tomografías computarizadas cone-beam (TCCB) de pacientes ≥ 16 años de edad, de ambos sexos, con al menos un tercer molar retenido o erupcionado con desarrollo radicular completo. Las características estudiadas fueron el número, longitud, diámetro y forma de las raíces. Resultados: Los terceros molares superiores presentaron con mayor frecuencia raíces fusionadas (57.9 por ciento) en forma cónica sobre su eje (27.2 por ciento). Los casos con raíces separadas mostraron más comúnmente una curvatura hacia distal en el tercio medio de la raíz vestíbulo-mesial (35 por ciento), mientras que la forma predominante de la raíz vestíbulo-distal fue la recta sobre su eje longitudinal (28.8 por ciento). Las formas más frecuentes de la raíz palatina fueron la recta sobre su eje longitudinal y la recta palatinizada conigual número de casos (18.7 por ciento), siendo ésta la que tuvo mayor longitud (11.7 ± 1.7 mm) y diámetro en sus diferentes tercios (cervical 4.8 ± 0.9 mm, medio 4 ± 1.1 mm y apical 2.8 ± 0.9 mm). Los terceros molaresinferiores presentaron mayormente dos raíces (75.9 por ciento) convergentes yseparadas por un septum óseo (38.1 por ciento), siendo la raíz vestíbulo-distal la que presentó mayor diámetro en sus diferentes tercios (4.1 ± 1 mm,3.4 ± 0.7 mm y 2.3 ± 0.6 mm, respectivamente). Conclusiones:Las características de las raíces de los terceros molares observadas en la TCCB se acercan a las descripciones anatómicas. Se observaron, además, múltiples variaciones en su forma, tanto en las fusionadas como en las separadas. Este aspecto morfológico debe ser tomado en cuenta para prever el grado de dificultad de la odontectomía del tercer molar.

Introduction: The root morphology of third molars is something thatcan make extraction more diffi cult, which is why research is needed intothe most common anatomical aspects of this characteristic. Objective:To understand the root morphology of the third molar. Material andmethod: 155 cone-beam computed tomography (CBCT) images ofpatients aged ≥ 16 years of both sexes with at least one retained orerupted third molar with complete root development were examined.The features assessed were: number, length, diameter, and shape ofthe roots. Results: The upper third molar was found to have a greaterfrequency of fused (57.9%) and cone-shaped roots (27.2%). Cases ofseparate roots most commonly displayed distal curvature towards themiddle third of the mesiobuccal root (35%), while the distobuccal rootwas more typically straight along its longitudinal axis (28.8%). Thepalatal root was most commonly either straight along its longitudinalaxis or its palatal side (18.7% in both cases), the latter being longer(11.7 ± 1.7 mm) and having a greater diameter in each of its threesections (cervical 4.8 ± 0.9 mm, middle 4 ± 1.1 mm, and apical 2.8 ±0.9 mm). The presence of two converging roots (75.9%) and two rootsseparated by an interdental septum (38.1%) was more common in lowerthird molars, with the distobuccal root having the greatest diameterin each of its three sections (cervical, 4.1 ± 1 mm, middle, 3.4 ± 0.7mm, and apical 2.3 ± 0.6 mm). Fused roots were longer (11.6 ± 1.8mm) and most commonly cone-shaped with distal tapering (27.7%).Conclusions: The characteristics observed in the CBCT images of theroots of the third molars were similar to those described in anatomicalliterature. Furthermore, multiple variations were found in their shape, inboth the fused and the separate root canals. This morphological aspectshould be taken into consideration in order to determine the degree ofdiffi culty of a third molar extraction.

Retenção prolongada de dente decíduo por impactação de dente supranumerário em criança de 12 anos / Tooth prolonged retention of deciduous tooth impaction supernumerary in children under 12 years

Dente supranumerário é definido como um distúrbio de desenvolvimento caracterizado pela presença de um ou mais elementos dentários fora do número considerado normal de uma arcada. A ocorrência dos supranumerários pode ocasionar uma variedade de complicações, como por exemplo, apinhamento de dentes permanentes, erupção retardada e/ou ectópica, rotação dentária, formação de diastema, desenvolvimento de lesões císticas, reabsorção de dentes adjacentes. Na maioria das vezes o diagnóstico da presença desse elemento é realizado por exame clínico e radiográfico de rotina. O objetivo do presente trabalho foi relatar um caso clínico de retenção prolongada de um dente decíduo e erupção retardada de um dente permanente em decorrência da presença de um elemento supranumerário diagnosticado apenas aos 12 anos de idade. Após a identificação do elemento supranumerário e análise de exames radiográficos complementares,foi realizada cirurgia para remoção dos elementos decíduo e supranumerário, bem como acompanhamento por três meses do processo eruptivo do elemento impactado,um segundo pré-molar inferior direito o qual se posicionou favoravelmente na arcada dentária. Concluiu-se que a detecção em momento oportuno e a remoção de elementos supranumerários, também respeitadas à necessidade e oportunidade cirúrgica, são importantes para evitar danos futuros à oclusão dos pacientes, devendo-se dar importância ao acompanhamento e evolução clínica do caso.

Supernumerary teeth is defined as a developmental disorder characterized by the presence of one or more dental elements out of a number considered normal arch. The occurrence of supernumerary can cause a variety of complications, such as crowding of the permanent teeth,delayed and / or ectopically erupting, tooth rotation, diastema training, development of cysticlesions, resorption of adjacent teeth. In most cases the diagnosis of the presence of this elementis made by clinical examination and routine radiographic. The aim of this study was to reporta case of prolonged retention of a primary tooth eruption and delayed a permanent tooth dueto the presence of a supernumerary element diagnosed only 12 years old. After identifying the supernumerary element and analysis of complementary radiographs, it was carried out surgeryto remove the elements deciduous and supernumerary and monitoring for 3 months of the eruptive process impacted element, a premolar law that favorably-positioned in the dental arch.It was concluded that the timely detection and removal of supernumerary elements also respected the need and surgical opportunity, are important to prevent future damage to the occlusion of patients, should be given importance to the monitoring and clinical outcome.

Prevenção da impacção de caninos permanentes inferiores: relato de caso / Prevention of permanent mandibular canine impactation: case report

O presente trabalho aborda um tema pouco explorado na literatura, a impactação de caninos inferiores permanentes, ilustrando o acompanhamento longitudinal de um caso clínico. O tratamento de canino inferior impactado é bastante complexo, envolvendo diferentes condutas, inclusive a sua extração. Logo, a prevenção de tal possibilidade constitui-se de extrema importância. Como meios preventivos, têm-se o diagnóstico e a intervenção precoce. O diagnóstico precoce permite a opção pela conduta terapêutica interceptadora, prevenindo a impactação do canino permanente e suas consequências. A intervenção precoce pode economizar do paciente tempo, custos, tratamentos mais complexos e injúrias a qualquer outro dente saudável.

[Prediction of maxillary canine impaction with panoramic radiographs]

The incidence of maxillary canine impaction is between 1% and 3% populations. Determining whether impaction will occur and timing the treatment modalities that are affected by impacted canine [s] are paramount for a successful out come, panoramic radiograph to identify canine impaction; not only is economical but treatment result will be more desirable. The aim of this investigation was to develop a reliable method for predictors of maxillary canine impaction on a panoramic radiograph. Sixty - four panoramic radiographs of mixed dentition patients were inspected to belong to two groups of patient with impacted and not impacted canines. 88 were found with no impaction and 40 with impacted canines. For predicting canine impaction panoramic radiographs were inspected for two indices: 1- The erupted lateral tooth were divided to fourfold zone from 4 to 1 sectors in mesiodistal dimension; therefore identified the unerupted permanent canines cusp tip location related to the erupted permanent lateral. 2-The internal angle between the long axis of the unerupted canine and a horizontal line between superior points of condyles was measured. The data were analyzed by descriptive statistics and logistic regression. All of not impacted teeth were found in sector I and II. [69.3% in sector I and 30.7% were placed in sector II]. 17.5% of impacted teeth were in sector I, 42.5% in sector II, 27.5% in sector Ill and 12.5% were placed in sector IV. Furthermore the mean angle for non impacted teeth was 74.72' and for impacted teeth was 67.12'. The location of canine cusp tip in panoramic radiograph is the most important factor in predicting probable impaction, but often, the angle of canine is not worth

El tercer molar mandibular, método predictivo de erupción / The mandibular third molar, an eruption predictive method

Una de las inquietudes de los odontólogos, principalmente de los especialistas en ortodoncia y cirugía bucal, es saber cuándo se hace necesario extraer los terceros molares o cuándo dejarlos para que completen con éxito su erupción. En este trabajo se pretende establecer un método predictivo sobre radiografías panorámicas que nos permita tomar la decisión acertada.