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)

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.

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.

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.

Dilemmas pertaining to three canals in the mesiobuccal root of a maxillary second molar: a case report

The mesiobuccal root of the maxillary molars is well known to pose a hindrance during endodontic therapy. Presented here is a case of a maxillary left second molar where three canals were located in its mesiobuccal root with the use of visual and diagnostic aids. Difficulties encountered during the process of unveiling the tooth's internal anatomy were discussed. The dilemmas encountered pertained to the root canal configuration, the nomenclature of the extra canals, and the justification for the presence of a third canal. The root canal configuration of 3-2-1 was confirmed for the mesiobuccal root using information gained from clinical, radiographic, and multi-detector computed tomography (MDCT) scan findings. This case demonstrates the need for efforts to locate extra canals in the mesiobuccal root of the maxillary molars as their internal anatomy remains a mystery.

Management of a maxillary first molar tooth with unusual mesiobuccal root anatomy

Sufficient knowledge on the root and root canal anatomy is essential for practicing root canal treatment. The mesiobuccal roots of maxillary molar teeth present an endodontic challenge due to their wide variability and complexity of their internal morphological landmarks. A review on the literature indicates that the prevalence of a third mesiobuccal root canal in the mesiobuccal root of maxillary molar teeth may reach 9%, and the root canal configuration usually is type XV (3-2). These reported data reveal the importance of absolute awareness for this anatomical aberration that requires special attention from dental practitioners while commencing root canal treatment in maxillary molar teeth. Hence, this article aims to report and describe the management of a maxillary first molar tooth with three mesiobuccal root canals, but with an unusual configuration.

Maxillary first molar with three canals in mesiobuccal root: A case report.

Knowledge of internal dental morphology is a complex and extremely important for planning and performing endodontic therapy. Proper location of additional canals in roots, especially of maxillary first molar, is very fundamental in high rate success of root canal therapy. This article describes the identification and treatment of a maxillary first molar exhibiting three canals in the mesiobuccal root.

Anatomia interna da raiz mésio-vestibular dos primeiros e segundos molares permanentes superiores / Internal anatomy of the mesiobuccal root of the first and second permanent upper molars

Objetivo: Esta pesquisa refere-se ao estudo da anatomia interna da raiz mésio-vestibular dos primeiros e segundos molares superiores permanentes. Material e método: Duzentos e vinte cinco molares tiveram a sua raiz mésio-vestibular seccionada ao nível amelo-cementário e, visualmente, com auxílio de sonda exploradora, foram selecionadas aquelas que apresentaram na região cervical, dois orifícos correspondentes às entradas dos condutos mésio-vestibular e mésio-palatino, perfazendo um total de cem raízes (44,44 %). Todas elas foram submetidas ao processo de diafanização, associada à injeção de hematoxilina, que confere transparência às raízes e coloração aos condutos, permitindo, assim, a avaliação tridimensional da anatomia dental interna. Resultados: A presença de dois condutos percorrendo toda a raiz e terminando separados em dois forames foi observada em 46% da amostra, sendo que 68% em altura apical distinta e, a percentagem de condutos que se fusionaram nos terços cervical, médio ou apical e terminaram em um forame foi de 53%. Encontrou-se, também, uma raiz com três condutos e oito dentes com uma raiz extra, correspondente ao canal mésio-palatino. Conclusão: Os resultados mostraram que a incidência expressiva de mais de um conduto na raiz mésio-vestibular e o complexo sistema de canais que ela apresenta, pode ter grande influência no sucesso dos tratamentos endodônticos dos molares superiores, exigindo, por isso, atenção especial do endodontista.

Aim: This research concerns the study of the internal anatomy of the mesiobuccal root of the first and second permanent maxillary molars. Material and methods: Two hundred and twenty five molars had their mesiobuccal root sectioned at the amelo-cemental. With the aid of the exploratory probe it was conducted a visual selection of the roots that presented at the cervical region two orifices corresponding to the entries of the mesiobuccal and mesiopalatal conduits. The total amount was of one hundred roots (44,44%). All of them underwent the process of diafanization associated with the injection of hematoxylin, what brings transparency to the roots and coloration to the ducts, thus enabling three-dimensional evaluation of the internal dental anatomy. Results: The presence of two conduits running through the entire root and ending in two separate foramina was observed in 46% of the sample, 68% in distinct apical height. The percentage of the conduits that merged at cervical, middle or apical thirds and ended in a foramen was of 53%. It was also found a root with three conduits and eight teeth with an extra root, corresponding to the mesio-palatal canal. Conclusions: The results showed that the expressive incidence of more than one conduit at the mesiobuccal root and the complex system of canals that it presents can have a great influence on the success of treatments of the upper molars, therefore requiring special attention from the endodontist.

Application of dental operative microscope in detecting the mesiobuccal root canal orifice of the maxillary first permanent molar / 上海第二医科大学学报

Objective To observe the effect of the dental operative microscope(DOM) and the ultrasonic apparatus in detecting the mesiobuccal root canal orifice of the maxillary first permanent molar(MFPM). Methods According to traditional method,the pulp chamber was opened and the second mesiobuccal root canals(MB2) were explored in 76 MFPM teeth.If MB2 was not found,then we modified the shapes of the pulp chambers and detected the orifices.At last,MB2,not found under naked eyes,was explored with DOM and ultrasonic technique. Results The detection rate of the second mesiobuccal orifice of MFPM was 81.6%.The rate was only 31.6% when using traditional method,while after modifying the shapes of the pulp chambers there was an increase of 30.2% under naked eyes and then another 19.7% increase was obtained by using DOM and ultrasonic apparatus.The distance between two mesiobuccal root canal orifices was(1.42?0.51) mm. Conclusion It is helpful to find some invisible orifice of MB2 by using DOM and ultrasonic technique,and it would be beneficial to improve the root canal therapy.

The canal system in the mesiobuccal root of the maxillary first molar / 대한치과보존학회지

This study is to investigate the canal system in the mesiobuccal root of the maxillry first molar. 61 maxillary first molars were randomly selected. Serial transverse sections were made perpendicular to the long axis of the mesiobuccal root. Each section was placed in 3% sodium hypochlorite for 24 hours and rinsed in water and dried. The resected surface was stained with 2% methylene blue dye and examined with stereomicroscope. 1. Canal configuration analysis showed that 36.1% of the specimen classified as type I, 16.4% as type II, 37.7% as type III and 9.8% as type IV. 2. Type II canal was merged in one canal within 1 to 4mm of the apex. 40% of type II canal converged at 2mm of the apex. 3. Type IV canal was divided into two canal within 2 to 4mm of the apex. 66.6% of type IV canal branched off at 2mm of the apex. 4. None of the sections had more than two main root canal. 5. 48.4% of the sections in 3mm with two canals contained an isthmusand more than 70% with two canals has isthmus at 4 to 5mm sections. 63.9% of the mesiobuccal root of maxillary first molar had two canaland 76.5% of sections with two canals in 5 MM had an isthmus. Because of this complexity the clinician should always search for extra canal carefullyand root canal system, including an isthmus, should be cleaned and shaped completelyand obturated three dimensionally for successful endodontic treatment.

Study on the length,number and transverse shape of the root canals of the first maxillary molars in vitro / 实用口腔医学杂志

Objective:To investigate the root length,number and the transverse shape of first maxillary molars using root sectioning technique. Methods:100 isolated first permanent maxillary molars from above 20 years old patients were collected. The roots were cross-sectioned in three parts(superior 1/3,middle 1/3 and apex 1/3) after measuring the length of roots. The transverse shape of root canals were observed under the stereomicroscope.The number and shape of root in three parts of roots were recorded. Results:The length of lingual root,MB and DB of the first maxillary molar is (13.82?1.51) mm;(13.06?1.12) mm and (11.64?0.85) mm respectively; complex degree of MB and DB of the first marxillar molar is very high. 51% double roots in superior 1/3 of MB were found. Above 50% dual roots in the middle 1/3and apex 1/3 in the mesiobuccal root of first maxillar molar were recorded. Conclusion:Root number and transverse configuration in MB and DB of first maxillary molar varied in different parts of roots; There may be double root canals in medium 1/3 and apex 1/3 in MB of first maxillary molar when one line type canal in superior 1/3 was found.