Morphology of the Second Mesiobuccal Canal in the Maxillary Second Molar / Morfología del Segundo Canal Mesiovestibular en el Segundo Molar Maxilar

SUMMARY: Failure to locate a complete canal system affects the prognosis of root canal treatment. A missed root canal is one of the most common reasons for failed root canal treatment. The prevalence of the second mesiobuccal canal in the maxillary second molar is relatively high and has a variety of configurations. Therefore, knowledge of its morphology is required in clinical endodontics. This review presented the canal in terms of its prevalence, classification, anatomical features, and the method for locating the second mesiobuccal canal in the maxillary second molar. Root canal treatment requires knowledge of tooth morphology, appropriate access preparation, and a thorough examination of the tooth's interior. Thus, clinicians should carefully employ various methods for assessing the anatomy of the entire root canal system to prevent failure in locating the second mesiobuccal canal. This canal can be located by modifying the access cavity design and utilizing specific instruments to improve the second mesiobuccal canal system visualization.

La falta de localización de un sistema completo de canal afecta el pronóstico del tratamiento de éste. La omisión de un tratamiento de canal es uno de los motivos más frecuentes por las que el tratamiento de canal fracasa. La prevalencia del segundo canal mesiovestibular en el segundo molar superior es relativamente alta y tiene una variedad de configuraciones. Por tanto, el conocimiento de su morfología es necesario en endodoncia clínica. Esta revisión presentó el canal en términos de su prevalencia, clasificación, características anatómicas y el método para localizar el segundo canal mesiovestibular en el segundo molar superior. El tratamiento de canal requiere conocimiento de la morfología del diente, una preparación adecuada del acceso y un examen exhaustivo del interior del diente. Por lo tanto, los dentistas deben emplear cuidadosamente varios métodos para evaluar la anatomía de todo el sistema de canales radiculares para evitar fallas en la localización del segundo canal mesiovestibular. Este canal se puede localizar modificando el diseño de la cavidad de acceso y utilizando instrumentos específicos para mejorar la visualización del sistema del segundo canal mesiovestibular.

Canal mesiovestibular 2 (MV2): como vencer as dificuldades durante seu tratamento / Second mesiobuccal canal (MB2): how to overcome the difficulties in treating it

Os canais radiculares, quando não tratados, podem ter um impacto direto na previsibilidade do tratamento endodôntico. Hoje, já se sabe que o canal mesiovestibular 2 (MV2) é o mais esquecido sem tratamento durante a terapia endodôntica e, quando isso acontece, a probabilidade de aparecimento de doença inflamatória na região periapical é de 4,5 a 6,5 vezes maior do que em dentes que tiveram todos os canais tratados. Sendo assim, o clínico deve conhecer informações importantes relacionadas às complexidades anatômicas que dificultam o acesso e exploração desse canal, bem como conhecer manobras que facilitam o seu tratamento, uma vez que localizar e negociar o MV2 sempre foi um grande desafio. O objetivo do presente estudo é mostrar os principais obstáculos enfrentados para localizar e tratar o canal MV2, e orientar como essas dificuldades podem ser superadas no dia a dia da clínica endodôntica (AU).

When not treated, root canals may affect the predictability of endodontic treatments directly. The second mesiobuccal root canal (2MB) is the canal most often missed and left untreated during endodontic treatments. The probability of inflammatory disease in the periapical region in these cases is 4.5 to 6.5 times greater than in teeth that have all canals treated. Therefore, clinical dentists should know the anatomical complexities that may complicate root canal access and exploration. As 2MB detection and negotiation are a great challenge, they should also be familiar with the procedures that facilitate treatment. This study describes the main obstacles to the location and treatment of the 2MB canal and discusses how these obstacles may be overcome in routine endodontic practice (AU).

Clinical study of root canal numbers in maxillary second primary molars / 口腔疾病防治

Objective@#To investigate the root canal numbers of maxillary second primary molars.@*Methods @#216 max illary second primary molars from 204 children aged 3-8 years old were selected. All the teeth need to do the root canal therapy. After opening the pulp chamber, the root canal were examined and determined with small size K file and 17％ethylene diaminetetraacetic acid (EDTA). Hand instruments were used for root canal preparation and then zinc-oxide iodoform paste was used for filling. @*Results @#216 maxillary second p rimary molars, 122 teeth had three root canals(56.5%), and 94 teeth had four root canals (43.5%). The incidence of second mesiobuccal canal (MB2) was 41.2%. There was no correlation between the incidence of the MB2 canal and gender and tooth position. @*Conclusion@# The root canals of maxillary second primary molars had more variations, and there was a high incidence of the second mesiobuccal canal.

Morphology of Mesiobuccal Root Canals of Maxillary First Molars: a comparison of CBCT scanning and Cross-sectioning

Abstract: The aim of this study was to evaluate the mesiobuccal root of maxillary first molars, according to the root canal configuration, prevalence and location of isthmuses at 3 and 6 mm from the apex, comparing cone-beam computed tomography (CBCT) analysis and cross sectioning of roots by thirds. Images of the mesiobuccal root of 100 maxillary first molars were acquired by CBCT and then roots were cross-sectioned into two parts, starting at 3 mm from the apex. Data were recorded and analyzed according to Weine's classification for root canal configuration, and Hsu and Kim's classification for isthmuses. In the analysis of CBCT images, 8 root canals were classified as type I, 57 as type II, 35 as type III. In the cross-sectioning technique, 19 root canals were classified as type I, 60 as type II, 20 as type III and 1 as type IV. The classification of isthmuses was predominantly type I in both CBCT and cross-sectioning evaluations for sections at 3 mm from the apex, while for sections at 6 mm from the apex, the classification of isthmuses was predominantly types V and II in CBCT and cross-sectioning evaluations, respectively. The cross-sectioning technique showed better results in detection of the internal morphology of root canals than CBCT scanning.

Resumo: O objetivo do presente estudo foi avaliar a raiz mésio-vestibular de primeiros molares superiores, de acordo com a configuração do canal radicular e com a prevalência e localização de istmos a 3 e a 6 mm do ápice, comparando a análise realizada em tomografia computadorizada de feixe cônico (TCFC) com a técnica de seccionamento transversal por terços. Foram obtidas imagens tomográficas das raízes mésio-vestibulares de 100 primeiros molares superiores, e em seguida, as raízes foram seccionadas em dois segmentos, iniciando nos 3 mm a partir do ápice. Os dados foram analisados de acordo com a classificação de Weine para configuração de canais radiculares, e de acordo com a classificação de Hsu e Kim para avaliação dos istmos. Na análise das imagens das TCFCs, 8 canais radiculares foram classificados como tipo I, 57 como tipo II, e 35 como tipo III. Na técnica de seccionamento transversal, 19 canais radiculares foram classificados como tipo I, 60 como tipo II, 20 como tipo III, e 1 como tipo IV. Na avaliação dos istmos, houve predominância do tipo I tanto na TCFC quanto na técnica de seccionamento transversal a 3 mm do ápice. Entretanto, a 6 mm do ápice, a classificação dos istmos foi predominantemente tipo V e II, na avaliação em TCFC e na técnica de seccionamento transversal, respectivamente. A técnica de seccionamento transversal demonstrou melhores resultados na detecção da morfologia interna dos canais radiculares avaliados do que a TCFC.

The morphology of maxillary first molars and root canals in Uyghur adults examined by cone-beam com-puted tomography / 实用口腔医学杂志

Objective:To analyze the morphological characteristics of maxillary first molars,mesiobuccal roots and the incidence of second mesiobuccal(MB2)roots in Uyghur adults.Methods:1 00 Uyghur adults with full dentition were included.The morphology of maxillary first molars and root canals were examined by cone beam computerized tomography(CBCT).The prevalence of MB2 and the difference between sexes were analysed.Results:Among 200 maxillary first molars,1 54(77%)teeth were with 3 roots and 3 ca-nals,42(21 %)with 3 roots and 4 canals,2(1 %)with 3 roots and 5 canals,1 (0.5%)was with 4 roots and 6 canal,1 (0.05%) with 4 roots and 7 canal.The percentage of type Ⅰ,Ⅱ,Ⅲ,Ⅳ and Ⅴ mesiobuccal roots was 77.0,1 3.5,9.0,0 and 0.5 respec-tively.The prevalence of MB2 was 22.32% in male and 21 .2% in female(P =0.901 ).Conclusion:The prevalence of MB2 in Uy-ghur adults is about 22% and the predominant morphology of maxillary first molarsmesiobuccal roots was type I.

Clinical study of the second mesiobuccal canal of maxillary second primary molars / 实用口腔医学杂志

The root canals of 95 maxillary second primary molars were explored by 10#file combined with 17%EDTA.The canal orifice was observed and orientated by endoscope.Hand instruments were used for root canal preparation and screw conveyor was used to fill the ca-nal with Vitapex paste.MB2 was found in 14 of the 95 molars(14.7%).MB2 orifice was usually located mesially along MB-P.

Clinical feature and treatment of the second mesiobuccal canals of maxillary molars / 实用口腔医学杂志

Objective:To discuss the clinical feature and treatment of second mesiobuccal canal (MB2)of permanent maxillary molars. Methods:The root canals of 106 maxillary first molars and 80 maxillary second molars were explored with small size K files. The frequency and morphology of root canals were recorded. The canals of all cases were instrumented by Ni-Ti rotary instruments Hero 642, and obturated with lateral condensation technique. The efficiency of preparation and obturation was analyzed with radiographs before and after treatment. Results:The frequency of MB2 canal in maxillary first and second molars were 82.1% and 45.0%. Most MB2 was very fine and negotiated by size 8 or 10 file combined with EDTA. No transportation, ledge, or perforation was found except that one hand file was separated. Good result of treatment was achieved in most cases. Conclusion:The incidence of MB2 canals of maxillary first molars was higher than that of second molars, and most of them were very fine. The MB2 canals can be negotiated with small size file combined with EDTA, and shaped well with Ni-Ti rotary instruments.