Morphology of the Second Mesiobuccal Canal in the Maxillary Second Molar

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.

Frecuencia y tipología del segundo conducto mesiovestibular en primeros molares superiores / Frequency and typology of the second mesiobuccal canal in maxillary first molars

Objetivos: Evaluar mediante microscopia quirúrgica la presencia del segundo conducto mesiovestibular (MV2) en el piso de la cámara pulpar de los primeros molares superiores, determinar su abordabilidad, establecer el calibre de lima que llegó al tercio apical y tipificar radiovisiográficamente su morfología se-gún la clasificación de Weine. Materiales y métodos: Se utilizaron 48 primeros molares superiores huma-nos extraídos. Sé tomaron radiovisografías preope-ratorias (Carestream 5200) en sentido orto radial y mesio-distal. Se realizó apertura y se localizó entra-da del MV2 con microscopio quirúrgico (Newton MEC XXI, Argentina) a 16 x. Se cateterizó MV1 y MV2 con limas tipo K #10 y #15 (Dentsply Maillefer). Se cortó raíz distovestibular para mejorar visualización ra-diovisográfica. Se tomó conductometria en sentido mesio-distal para establecer la tipología. Se compa-raron frecuencias y porcentajes mediante test de Chi-cuadrado con corrección de Yates, prueba exac-ta de Fisher y test z para diferencia de proporcio-nes. Se calcularon intervalos de confianza 95% para porcentajes mediante método score de Wilson. Re-sultados: El 54% (26 casos) presentó MV2. De los 26 MV2, el 77% (20 casos) fueron abordables, porcen-taje significativamente mayor al 23% no abordable (z=3,62; P<0,05). Al hacer cateterismo, hubo asocia-ción significativa entre tipo de conducto (MV1 y MV2) y calibre de lima que llegó al tercio apical (Chi-cua-drado=29,12; gl=1; P<0,05). La tipología I (58%) fue significativamente mayor que las tipologías II (21%) y III (21%) (P<0,05 para ambas comparaciones). Con-clusión: El alto porcentaje de piezas que presentó MV2 evidencia la importancia clínica de detectarlo y tratarlo correctamente. Dado el alto porcentaje de piezas donde fue abordable, se concluye que el clíni-co debe tener conocimiento, destreza y la tecnología necesaria para poder abordarlo. Si bien la tipología I (58%) fue la más encontrada, cuando el MV2 termina en foramen independiente (tipo III), su omisión puede conducir al fracaso del tratamiento (AU))

Objectives: To evaluate by surgical microscopy the presence of second mesiobuccal canal (MB2) in the pulp chamber floor of the maxillary first molars, determine its approachability, establish the caliber of the file that reached the apical third, and radiographically typify its morphology according to Weine ́s classification. Materials and methods: 48 extracted human maxillary first molars were used. Preoperative radiovisographies (Carestream 5200) were taken in ortho-radial and mesio-distal direction. Coronal access was made and the entrance of MB2 was located with a surgical microscope (Newton MEC XXI, Argentina) at 16x. MB1 and MB2 were catheterized with K files #10 and #15 (Dentsply Maillefer). Distobuccal root was cut to improve radiovisographic visualization. Conductometry was taken in mesio-distal direction to establish the typology. Frequencies and percentages were compared using Chi-square test with Yates correction, Fisher's exact test and z test for difference in proportions. 95% confidence intervals were calculated for percentages using Wilson score method. Results: 54% (26 cases) presented MB2. Of the 26 MB2, 77% (20 cases) were approachable, a significantly higher percentage than those not approachable (z=3.62; P<0.05). When performing catheterization, there was a significant association between type of canal (MB1 and MB2) and file caliber that reached the apical third (Chi-square=29.12; df=1; P<0.05). Typology I (58%) was significantly higher than typologies II (21%) and III (21%) (P<0.05 for both comparisons). Conclusion: The high percentage of specimens that showed MB2 evidence the clinical importance of detecting and treating it correctly. Given the percentage of pieces where it was approachable (77%), it is concluded that the clinician must have the knowledge, skill and necessary technology to be able to approach it. Although typology I (58%) was the most found, when MB2 ends an independent foramen (type III), its omission can lead to treatment failure (AU)

Segundo Conducto Mesiovestibular en Molares Superiores: Prevalencia y Análisis Anatómico Mediante Tomografía Computarizada de Haz Cónico / Second Mesiobuccal Canal in Maxillary Molars: Prevalence and Anatomical Analysis Through Cone Beam Computed Tomography

El objetivo de este estudio fue utilizar la Tomografía Computarizada de Haz Cónico (TCHC) para investigar la configuración anatómica, prevalencia y distribución del conducto mesiovestibular Dos (MV2) en molares superiores de una subpoblación chilena, considerando variables como la presencia del conducto MV2, la clasificación de Vertucci, el género y edad. Estudio observacional de corte transversal. La muestra consistió en Tomografías Computarizadas de Haz Cónico tomadas en la clínica odontológica de la Universidad Andrés Bello (Viña del Mar). Se calculó el tamaño muestral utilizando la fórmula de población conocida, lo que resultó en 262 tomografías. Los examinadores se calibraron utilizando el coeficiente Kappa de Cohen, para luego analizar las variables mediante un estudio imagenológico utilizando el software I-CAT Visión. Se analizaron 439 primeros y segundos molares superiores. La prevalencia del conducto MV2 en primeros molares fue del 63,74 %, mientras que, en segundos molares, fue del 20,04 %. La prevalencia en primeros molares fue mayor en hombres (73,86 %) que en mujeres (58,62 %), mientras que, en segundos molares, fue del 15,81 % en mujeres y del 28,41 % en hombres. En relación con la edad, en los primeros molares la diferencia fue significativa en el rango de 18 a 40 años (66,49 %). En cuanto al tipo de configuración según Vertucci (2005), el 70 % de los primeros molares presentó una configuración Tipo II, y un 23,65 % Tipo IV, con resultados similares en los segundos molares. El presente estudio demostró que los conductos MV2 son frecuentes en la población analizada, especialmente en los primeros molares, y que la configuración Tipo II es la más prevalente. Además, se observó una mayor prevalencia en hombres y en el rango de 18 a 40 años. Estos hallazgos proporcionan información relevante sobre la anatomía radicular en la población y pueden contribuir a mejorar los resultados de tratamiento.

SUMMARY: The aim of this study was to use Cone-beam Computed Tomography (TCHC) to investigate the anatomical configuration, prevalence, and distribution of the Second Mesiobuccal (MB2) canal in upper molars of a Chilean subpopulation, considering variables such as the presence of MB2 canal, Vertucci classification, gender, and age. Cross-sectional observational study. The sample consisted of TCHC scans taken at the dental clinic of Universidad Andrés Bello (Viña del Mar). The sample size was calculated using the formula for known population, resulting in 262 scans. The examiners were calibrated using Cohen's Kappa coefficient, then the variables were analyzed through an imaging study using I-CAT Vision software. 439 first and second upper molars were analyzed. The prevalence of MB2 canal in first molars was 63.74 %, while in second molars, it was 20.04 %. The prevalence in first molars was higher in males (73.86 %) than in females (58.62 %), while in second molars, it was 15.81 % in females and 28.41 % in males. Regarding age, in first molars the difference was significant between the age range of 18 to 40 years (66.49 %). Regarding the type of configuration according to Vertucci, 70 % of the first molars had Type II configuration, and 23.65 % had Type IV, with similar results in second molars. The present study demonstrated that MB2 canals are frequent in the analyzed population, especially in first molars, and Type II configuration is the most prevalent. Additionally, a higher prevalence was observed in males and in the age range of 18 to 40 years. These findings provide relevant information about root anatomy in the studied population and can contribute to improving treatment outcomes.

Root canal treatment of maxillary second molar with three mesial buccal root canals: a case report and literature review / 口腔疾病防治

Objective@#To explore the key points of clinical diagnosis and treatment of three mesiobuccal root canals.@*Methods@# In the procedure of endodontic therapy for the upper left second molar with pulpitis, through root canal exploration under a dental microscope and cone beam CT (CBCT)-assisted imaging examination, it was confirmed that the left upper second molar contained 3 roots and 5 root canals, among which the third root canal existed in the mesiobuccal root. Combined with perfect root canal preparation, cleaning, disinfection, filling and minimally invasive inlay repair, the clinical symptoms were eliminated. The patients were followed up and the related literatures were reviewed. @* Results @# One- and two-year follow-ups showed that the tooth had no discomfort and could be used normally. X-ray revealed that the filling was complete, and the periapical tissue was normal. The results of the literature review showed that the incidence of three mesiobuccal root canals in maxillary second molars was 0.11%-4.2%. It is difficult to find additional root canals only by X-ray imaging. Dentists should further determine the number and anatomical shape of root canals by CBCT and operating microscopy. When there are three mesiobuccal root canals in maxillary molars, dentists should avoid overpreparation. Healthy tooth tissue is the key to good prognosis. @* Conclusion@#During root canal therapy, clinicians should consider the anatomical variation of the root canal, should always be alert to the existence of an extra root canal, and should use CBCT, operating microscopy, ultrasound and various auxiliary instruments to locate and treat the variant root canal.

Clinical and radiographic examination compared to microscopic examination in the detection of anatomical features of mesiobuccal canals in maxillary first molars: a diagnostic study / Comparación entre examen radiológico y clínico con examen microscópico en la detección de características anatómicas de los canales mesiobucales en los primeros molares maxilares: un estudio diagnóstico

SUMMARY: The aim of the present study was to determine the accuracy, sensitivity, and specificity of the clinical and radiographic examination (CRE) method compared to the examination with the dental operating microscope (DOM) on the detection of anatomical features of mesiobuccal canals in maxillary first molars. One hundred maxillary first molars were selected to assess the number of canals orifice entrances, accessibility, and ending of their mesiobuccal canals using the CRE method and the examination with the DOM. The diagnostic tests of the CRE exhibited, in general, high levels of accuracy, sensitivity, and specificity. However, low levels of these outcomes occurred, mainly, on the detection of the number of canals entrance orifices of the mesiobuccal root. The statistically significant differences (p<0.05) occurred for accessibility and ending of canals in 61 of the 62 cases (out of 100) when two of them were present: 2 accessible root canals (48 cases; 77.42 %), and 1 accessible and 1 inaccessible canals (13 cases; 20.97 %); 1 foramen after fusion (18 cases; 29.03 %), 2 foramens (30 cases; 48.39 %), and 1 foramen and 1 blind foramen (13 cases; 20.97 %). This study proves that the clinical and radiographic method (still the most commonly used worldwide) can't be trusted absolutely in situations of complex internal anatomy regarding the mesiobuccal root canals of maxillary first molars.

RESUMEN: El objetivo del presente estudio fue determinar la precisión, sensibilidad y especificidad del método de examen clínico y radiográfico (ECR) en comparación al examen con el microscopio quirúrgico dental (MQD) en la detección de características anatómicas de los canales mesiovestibulares en primeros molares maxilares.Se seleccionaron 100 primeros molares maxilares para evaluar el número de entradas de los canales, la accesibilidad y la terminación de sus canales mesiovestibulares utilizando el método ECR y el examen con el MQD.Las pruebas de diagnóstico del ECR exhibieron, en general, altos niveles de precisión, sensibilidad y especificidad. Sin embargo, también hubo niveles bajos de estos resultados, principalmente, en la detección del número de orificios de entrada a los canales de las raíces mesiovestibulares. Hubo diferencias estadísticamente significativas (p<0,05) para la accesibilidad y terminación de los canales en 61 de los 62 casos (del total de 100), cuando dos de ellos estaban presentes: 2 canales radiculares accesibles (48 casos, 77,42 %), y 1 accesible y 1 inaccesible (13 casos, 20,97 %). Después de la fusión, un orificio (18 casos, 29,03 %), 2 orificios (30 casos, 48,39 %) y 1 orificio más otro, ciego (13 casos, 20,97 %). Este estudio demuestra que no se puede confiar plenamente en el método clínico y radiográfico (todavía el más utilizado en todo el mundo), cuando existe una anatomía interna compleja de los canales de la raíz mesiovestibular de los primeros molares superiores.

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).

Management of maxillary first molar with six canals using operating microscope

The purpose of this article was to highlight the importance of having a thorough knowledge about the root canal morphology. This case report highlights the unusual anatomy of a maxillary first molar with three mesiobuccal (MB) canals, two palatal canals, and one distobuccal canal which is extremely rare. The use of operating microscope was crucial, both for the detection and for the management of the additional canals. The use of surgical operating microscope and digital radiograph showed that MB root had Type 3-1 of Gulabivala classification and palatal canal showed Vertucci's Type II canal morphology This report describes and discusses the identification of variation in canal morphology of maxillary first molar and the use of latest adjuncts in successfully diagnosing and negotiating them.

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.

Prevalence of Unclassified Root Canal Configuration in Permanent Maxillary First Molar in Indian Population.

Background: If a canal is left untreated, it is a foci of infection. Therefore, it is critical to know the usual configuration of the root canal along with the variations in root canal anatomy, in order to keep the cause of endodontic failure to a minimum. Aim: This study investigated the canal configuration in maxillary first permanent molar mesiobuccal root radiographically followed by histological evaluation in Indian population. Methods: Endodontic access preparation was performed on 100 human permanent maxillary Ist molars and all the canals were explored. The mesiobuccal root was separated and radiographed in mesiodistal and buccolingual direction. India ink dye was injected actively in the root canal of each sample. The root samples were prepared for histological viewing. The slides made were observed under light microscope and canal configurations were tabulated. Results: The radiographic interpretations by observers were correlated with histological findings and analyzed statistically (p value). The radiographic findings revealed a good inter observer agreement (Cohen kappa). On matching histological and radiographic interpretations, it revealed 69.2% Vertucci type I predominance. New unclassified canal configurations were also observed. Conclusion: To divulge three dimensional architecture of the root canal, application of alone conventional radiography is not enough.

Evaluación de la frecuencia, ubicación y tipos de itsmos en raíces mesiobucales de primeros molares maxilares: un estudio ex vivo / Evaluation of Isthmus frequency, location, and types in mesiobuccal roots of first maxillary molars: an ex vivo study

El objetivo fue describir la configuración interna del sistema canalicular de la raíz mesiobucal (MB) del primer molar maxilar, identificando el número de canales junto a la frecuencia, ubicación y tipos de itsmo a 1, 3 y 5 mm del ápice. Esta investigación fue aprobado por el comité de ética. Se realizó un estudio descriptivo ex vivo de corte transversal. Molares extraídos fueron limpiados, desinfectados y fijados en formalina al 10 %. Se identificó la raíz MB y se obtuvieron cortes transversales (3) a 1, 3 y 5 mm desde apical a coronal, identificadas como secciones A, B y C. Ciento cincuenta secciones fueron teñidas con azul de metileno y observadas bajo microscopio óptico, tanto en la superficie apical como coronal, y analizadas mediante el programa ImageJ. Se obtuvieron estadísticas descriptivas (media ± DE), y mediante las prueba ANOVA y chi-cuadrado de Pearson se compararon las secciones a diferentes niveles. Se observaron un total de 445 canales radiculares, 289 correspondieron a canales accesorios. El 41,6 % fueron canales mesiobucales secundarios (MB2) y 5,1 % un tercer canal accesorio. Se observaron con mayor frecuencia istmos Tipo I (48), seguidos de Tipo IV (26); los Tipos II, III y V no superaron el 15 %. De acuerdo con la prueba de chi-cuadrado de Pearson, existen diferencias significativas entre los tipos istmos y distancia del ápice (p> 0,001). La incidencia del Tipo I fue mayor cerca del ápice, con un descenso hacia los 3,0 mm. Se observó una compleja morfología del sistema canalicular apical en la raíz MB, que explica su baja tasa de éxito cuando son tratados con endodoncia. Las variaciones anatómicas, tales como MB2 o más canales accesorios e istmos deben ser considerados en la planificación y realización del tratamiento de endodoncia convencional o cirugía apical, con el fin de lograr procedimientos más exitosos. Se recomienda que las apicectomías se extiendan por lo menos a 3,3 mm del ápice.

The aim was to describe the internal configuration of the canalicular system of the mesiobuccal root (MB) of the maxillary first permanent molar, identifying the number of canals and isthmus frequency, location, and types at 1, 3 and 5 mm from the apex. This research was approved by the ethics committee. A descriptive ex vivo cross-sectional study was conducted. Extracted molars were cleaned, disinfected and fixed in 10% buffered formalin. The non-instrumented MB root was identified and 3 cross sections at 1, 3 and 5 mm from apical to coronal identified as A, B and C were obtained. 150 sections were stained with methylene blue and observed under microscope, in both apical and coronal surface using the ImageJ program. Descriptive statistics (Mean±SD) was obtained, and ANOVA and Pearson chi-square tests were used to compare the sections at different levels. A total of 445 root canals were observed, 289 corresponded to accessory canals. 41.6% were secondary mesiobuccal canal (MB2) and 5.1% a third accessory canal. The isthmus observed were Type I (48), followed by Type IV (26); Types II, III and V did not exceed 15%. According to the Pearson chi-square test, there are significant differences between the isthmus types and distance of the apex (p> 0.001). The incidence of Type I was greater near the apex, with a decline towards 3.0 mm. A complex morphology of the apical maxillary MB root system was found, and explains their low success rate when treated endodontically. Anatomical variations such as MB2, accessory canals and isthmus should be considered when planning and conducting endodontic treatment or apical surgery, in order to achieve more successful procedures. It is recommended that apicectomies extend at least 3.3 mm from the apex.

Presence of Mesiobuccal 2 and Mesiobuccal 3 Canal in Maxillary First Molar: An Illusion.

Successful endodontic treatment involves a proper access cavity preparation, biomechanical principles, and three-dimensional obturation. Thus, the clinician should have a through knowledge of anatomy and morphology of the root canal system. Failure in root canal therapy may be due to inability in locating the canal and its proper debridement. The configuration and a number of root canals in the maxillary first molars have been discussed for more than half a century. Maxillary first molars commonly present with three roots and three canals, with a second mesiobuccal canal (MB2) and (MB3). The current case reports describe the presence of extra canals MB2 and MB3 in a maxillary first molar.

Assessment of Mesial Root Morphology and Frequency of MB2 Canals in Maxillary Molars using Cone Beam Computed Tomography / Determinación de la Morfología de la Raíz Mesial y la Frecuencia del Canal MB2 en Molares Maxilares usando Tomografía Computadorizada de Haz Cónico

The aim of this study was to assess the morphology of the mesial root canal system of maxillary molars and the frequency of MB2 canals using cone-beam computed tomography (CBCT). A total of 1374 teeth, first maxillary (1MS, n= 802) and second maxillary molars (2SM, n= 572) of 508 Chilean patients between 8 to 77 years were evaluated through CBCT. The mesiobuccal root was evaluated in all three thirds. Root canal morphology was classified according to Vertucci's method. Data were analyzed by Pearson's Chi-square and Cuzick trend tests. MB2 canal frequency in 1MS was 73.44% and in 2MS 42.48%. The most frequent morphology in 1MS and 2MS were Vertucci type II and I, respectively. No statistically significant association was found between frequencies and side or according to gender (P>0.05). A positive association was found as the age increased in both 1MS and 2MS (P<0.001 and P= 0.023, respectively). Given the anatomical complexity of the mesiobuccal root and the frequent presence of the MB2 canal, the clinician must assume the existence of two canals in this root. CBCT scanning is a good way to initially identify this canal in the different root thirds.

Determinar la morfología del sistema de canales de la raíz mesial de molares maxilares y la frecuencia del canal MB2 usando tomografía computadorizada de haz cónico (TCHC). Un total de 1374 dientes, primeros molares maxilares (1MS, n= 802) y segundos molares maxilares (2MS, n= 572) de 508 pacientes Chilenos entre 8 y 77 años fueron evaluados a través de la TCHC. Se evaluó la raíz mesiobucal en todos sus tercio. La clasificación de Vertucci fue utilizada para determinar la morfología del sistema de canales. Los datos fueron analizados con los test Chi-Cuadrado de Pearson y la prueba de tendencia de Cuzick. La frecuencia del canal MB2 para el 1MS fue 73,44% y el 2MS 42,48%. La morfología mas frecuente en el 1MS y 2MS fueron el tipo II y I de Vertucci, respectivamente. No se encontró asociación significativa entre la frecuencia y el lado o sexo (p>0,005). Una asociación positive fue encontrada a medida que aumentaba la edad en ambos 1MS y 2MS (p<0,001 y p= 0,023, respectivamente). Dada la complejidad de la anatomía de la raíz mesiobucal y la frecuente presencia del canal MB2, el clínico debe asumir la existencia de dos canales en esta raíz. La TCHC es una buena manera de identificar tempranamente el canal en los diferentes tercio radiculares.

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.

Demystifying the mesiobuccal root of maxillary first molar using cone‑beam computed tomography.

Context: Imaging techniques and endodontics are inseparable from each other as the former have always been the cornerstone for successful endodontic diagnosis and treatment. Aims: The objective of this study was to detect the presence of extra canals in the mesiobuccal root of the maxillary first molar using cone‑beam computed tomography (CBCT). Materials and Methods: In this study, 75 freshly extracted human maxillary first molars were mounted on arches and exposed to CBCT and digital radiography (control). The incidence of additional canals is then evaluated using CBCT and the teeth identified with additional canals were marked and again exposed to RVG. Statistical Analysis Used: The results were analyzed by three examiners two endodontists and an oral radiologist to eliminate bias. Inter and intra rater agreement was analyzed using the kappa coefficient. Results: Statistical analysis revealed the incidence of extra canals to be at 47.1% with the difference between the readings of the 3 examiners being statistically insignificant. Conclusions: CBCT can be considered an advanced diagnostic tool for primary and secondary endodontic treatments.

Maxillary third molar with three canals in mesiobuccal root:A case report / 实用口腔医学杂志

This case report presents an extracted maxillary third molar,which have 3 separate roots with 5 canals,the canal configuration in mesiobuccal root are 3 separate orifices and canals,1 apical foramen.The clinician should be aware of this anatomical variation,avoid the missed canals.

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.

Endodontic Management of Maxillary Molar With Six Root Canals - A Case Report.

The aim of the present case report is to describe the unusual root canal anatomy of maxillary first molar with six canals, three in mesiobuccal root, two in distobuccal root and one in palatal root. This article highlights the importance of modifying the access opening and magnification in location of the additional canal orifices.

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.

Piecewise straight line approximation of curve existing in slightly curved mesiobuccal root canal of mandibular first molar: a radiographic investigation / Aproximación a segmentos de línea recta en la curva existente del canal radicular mesiobucal ligeramente curvado del primer molar inferior: una investigación radiográfica

The aim of this study was to radiographically investigate the curve existing in slightly curved mesiobuccal canal of mandibular first molar by applying Piecewise straight line approximation. Extracted human mandibular molars were radiographed and one hundred radiographs were selected whose mesiobuccal canal showed slight curvature (10-20°) according to Schneider's method. The curves were traced and analyzed using Piecewise straight line method. Each curve was considered as a unit consisting of six different pieces of straight lines joining at seven specific points and the angle of curvature at these points was determined using the slope formula. All curves analyzed in this study had varying degrees of curvatures at different points on the curve. Maximum curvature (0.40°) was recorded at the middle third of the root canal. Within the limitation of the study, significant curvature occurs through out the curve existing in the mesiobuccal canal of mandibular first molar and the middle third of the curve showing greater degree of curvature. There is a possibility of greater curvature occurring in the coronal third of the curve. Though three dimensional studies would be more appropriate, Piecewise straight line approximation may be a better method than existing methods to simulate canal geometry.

El objetivo de este estudio fue investigar radiográficamente la curva existente en el canal radicular mesiobucal ligeramente curvado del primer molar inferior mediante la aplicación de aproximaciones a segmentos de línea recta. Se utilizaron molares inferiores humanos extraídos que fueron radiografiados. Fueron seleccionadas, según el método de Schneider, 100 radiografías cuyo canal mesiobucal mostró una ligera curvatura (10-20°). Las curvas fueron delineadas y analizadas mediante el método de aproximación a segmentos de línea recta. Cada curva se consideró como una unidad que consta de seis diferentes segmentos de línea recta que unen a siete puntos específicos y el ángulo de curvatura en estos puntos se determinó utilizando la fórmula de la pendiente. Todas las curvas analizadas en este estudio tenían diversos grados de curvaturas en diferentes puntos de la curva. La curvatura máxima (0,40°) se registró en el tercio medio del canal radicular. Dentro de la limitación del estudio, una curvatura significativa se produce a través de la curva existente en el canal mesiobucal del primer molar inferior y el tercio medio de la curva que muestra un mayor grado de curvatura. Existe la posibilidad que ocurra una mayor curvatura en el tercio coronal de la curva. Aunque un estudio tridimensional sería más apropiado, la aproximación a segmentos de línea recta puede ser un mejor método que los existentes para simular la geometría del canal.

In-depth morphological study of mesiobuccal root canal systems in maxillary first molars: review

A common failure in endodontic treatment of the permanent maxillary first molars is likely to be caused by an inability to locate, clean, and obturate the second mesiobuccal (MB) canals. Because of the importance of knowledge on these additional canals, there have been numerous studies which investigated the maxillary first molar MB root canal morphology using in vivo and laboratory methods. In this article, the protocols, advantages and disadvantages of various methodologies for in-depth study of maxillary first molar MB root canal morphology were discussed. Furthermore, newly identified configuration types for the establishment of new classification system were suggested based on two image reformatting techniques of micro-computed tomography, which can be useful as a further 'Gold Standard' method for in-depth morphological study of complex root canal systems.