Maxillary Molar Root Canal Morphology Using Cone-Beam Computed Tomography: An Epidemiological Study from Shandong Province, China / Morfología del Conducto Radicular del Molar Maxilar Mediante Tomografía Computarizada de Haz Cónico: Un Estudio Epidemiológico de la Provincia de Shandong, China

SUMMARY: The objective of this study was to evaluate the maxillary molar root canal morphology in individuals from the Shandong province, China, using cone-beam computed tomography (CBCT) and classify it based on Ahmed et al. (2017) classification system to obtain a reference for clinical diagnosis and treatment. From December 2020 to June 2021, we screened CBCT data of 1,619 patients at the Jinan Stomatological Hospital who had been indicated for CBCT because of various oral abnormalities. The root and root canal morphologies of all teeth were statistically analyzed, and the root canal morphology was classified based on Ahmed et al. (2017) classification system. In the maxillary molars, three roots were the most common, accounting for 99.24 % and 74.61 % of all maxillary first and second molars, respectively. Two roots were the second most common, accounting for 0.66 % and 17.29 % of all maxillary first and second molars, respectively. Root morphology variation, e.g., fusion or furcation defect, was present in 22 (0.76 %) maxillary first molars and 765 (25.39 %) maxillary second molars, with the most common being mesiobuccal and distobuccal root fusion. Detection rates of a second mesiobuccal canal (MB2) in the maxillary first and second molars were 48.5 % and 26.5 %, respectively. Among age groups, the frequency of MB2 was the highest in the 15-24-year-old group and lowest in the 55-64-year-old group. Bilateral MB2 root canals were present in 64.8 % and 48.4 % of the maxillary first and second molars, respectively. Men and women accounted for 60.6 % and 67.8 % of the maxillary first molars, respectively, and 51.7 % and 45.6 % of the maxillary second molars, respectively. According to Ahmed et al. (2017) classification of root canal morphology, 18 and 22 root canal configurations were found in 1,453 right maxillary first molars and 1,444 left maxillary first molars, respectively. The right maxillary first molars showed three two-rooted, 14 three-rooted, and one four-rooted type. The left maxillary first molars showed two one-rooted, six two-rooted, and 14 three-rooted types. According to Ahmed et al. (2017) classification of root canal morphology, 43 and 45 root canal configurations were found in 1,507 right maxillary second molars and 1,506 left maxillary second molars, respectively. The right maxillary second molars showed 17 one-rooted, 16 two- rooted, eight three-rooted, and two four-rooted types. The left maxillary second molars showed 19 one-rooted, 13 two-rooted, 12 three- rooted, and one four-rooted type. This study showed that the maxillary molar root canal morphology is diverse in the Shandong province. Ahmed et al. (2017) classification system provides a clear description of the root canal morphology. CBCT can be used to study complex root and root canal morphologies.

El objetivo de este estudio fue evaluar la morfología del conducto radicular del molar superior en individuos de la provincia de Shandong, China, utilizando tomografía computarizada de haz cónico (CBCT) y clasificarla con base en el sistema de clasificación de Ahmed et al. (2017) para obtener una referencia para diagnóstico clínico y tratamiento. Desde diciembre de 2020 hasta junio de 2021, analizamos los datos de CBCT de 1619 pacientes en el Hospital Estomatológico de Jinan a quienes se les indicó CBCT debido a diversas anomalías orales. Las morfologías de la raíz y del conducto radicular de todos los dientes se analizaron estadísticamente, y la morfología del conducto radicular se clasificó según el sistema de clasificación de Ahmed et al. (2017). En los molares superiores, tres raíces fueron las más comunes, representando el 99,24 % y el 74,61 % de todos los primeros y segundos molares superiores, respectivamente. Dos raíces fueron las segundas más comunes, representando el 0,66 % y el 17,29 % de todos los primeros y segundos molares superiores, respectivamente. La variación de la morfología de la raíz, por ejemplo, fusión o defecto de furcación, estuvo presente en 22 (0,76 %) primeros molares superiores y 765 (25,39 %) segundos molares superiores, siendo la fusión radicular mesiovestibular y distovestibular la más común. Las tasas de detección de un segundo canal mesiovestibular (MB2) en los primeros y segundos molares superiores fueron del 48,5 % y 26,5 %, respectivamente. Entre los grupos de edad, la frecuencia de MB2 fue más alta en el grupo de 15 a 24 años y más baja en el grupo de 55 a 64 años. Los conductos radiculares MB2 bilaterales estaban presentes en el 64,8 % y el 48,4 % de los primeros y segundos molares superiores, respectivamente. En los hombres y en las mujeres representaron el 60,6 % y el 67,8 % de los primeros molares superiores, respectivamente, y el 51,7 % y el 45,6 % de los segundos molares superiores, respec- tivamente. Según la clasificación de la morfología del conducto radicular de Ahmed et al. (2017) se encontraron configuraciones de conducto radicular 18 y 22 en 1453 primeros molares superiores derechos y 1444 primeros molares superiores izquierdos, respectivamente. Los primeros molares superiores derechos mostraron tres tipos de dos raíces, 14 de tres raíces y uno de cuatro raíces. Los primeros molares superiores izquierdos mostraron dos tipos de una raíz, seis de dos raíces y 14 de tres raíces. Según la clasificación de la morfología del conducto radicular de Ahmed et al. (2017) se encontraron configuraciones de conducto radicular 43 y 45 en 1507 segundos molares superiores derechos y 1506 segundos molares superiores izquierdos, respectivamente. Los segundos molares superiores derechos mostraron 17 tipos de una raíz, 16 de dos raíces, ocho de tres raíces y dos de cuatro raíces. Los segundos molares superiores izquierdos mostraron 19 de una raíz, 13 de dos raíces, 12 de tres raíces y uno de cuatro raíces. Este estudio mostró que la morfología del conducto radicular del molar superior es diversa en la provincia de Shandong. El sistema de clasificación de Ahmed y colaboradores proporciona una descripción clara de la morfología del conducto radicular. CBCT se puede utilizar para estudiar morfologías complejas de raíces y conductos radiculares.

Protocolo para diafanización dental / Protocol for dental diafanization

Antecedentes: La Diafanización dental es una técnica que permite transparentar los dientes haciendo visible la anatomía interna de los conductos radiculares ofreciendo una herramienta pedagógica económica y confiable; sin embargo, la literatura no reporta protocolos estandarizados para obtener una diafanización dental predecible. Objetivo: Obtener un protocolo estandarizado para diafanización dental, como modelo educativo, a partir de la revisión de la literatura y la realización de un estudio piloto. Materiales y Métodos: Se realizó una búsqueda sistemática en las bases de datos Scopus y Medline con los términos Mesh "root canal", "diaphonization", "clearing", "morphology" anatomy", y se estructuró una tabla de extracción con las variables más representativas para establecer las 3 fases de la Diafanización, a. Descalcificación, se evaluó Ácido Nítrico 5% (HNO3), Ácido Fórmico 10% (CH2O2) y EDTA 10%, b. Deshidratación, se empleó Alcoholes etílicos ascendentes, c. Clarificación, se evaluó Metil Salicilato y Aceite de Inmersión Sintético. Se seleccionaron 54 dientes, 36 sin endodoncia, y 18 con endodoncia, y se distribuyeron en dos grupos: Grupo A. Dientes sin endodoncia, Grupo B. Dientes con endodoncia, constituidos por 18 subgrupos que estaban definidos de acuerdo al tipo de descalcificante, momento de aplicación medio de contraste y medio de Clarificación. Resultados: El Ácido Nítrico al 5% pese a que fue el más corrosivo, permitió el mayor flujo y accesibilidad para el medio de contraste (Tinta China) en especímenes sin endodoncia. De igual manera, el Ácido Fórmico al 10%, preservó la estructura de los dientes tratados endodónticamente. El Metil Salicilato como clarificante, brindó mejores resultados visuales alcanzando una mayor transparencia. Conclusiones: El desarrollo de un estudio piloto para estandarizar técnicas de diafanización en odontología, permite la estructuración de un protocolo educativo que posibilita conocer la gran variabilidad anatómica de los dientes y la comprensión y análisis de los dientes que han si do tratados endodóncicamente, aportando una herramienta pedagógica para la comprensión de la anatomía radicular. El uso de Ácido Fórmico al 10%, en dientes con tratamiento de endodoncia y de Ácido Nítrico 5% en dientes sin endodoncia, c on una transparencia alcanzada por el uso del Metil Salicilato, muestran los mejores resultados visuales en anatomía y obturación endodóntica.

Background: Dental diaphonization is a technique that allows the teeth to be made transparent, making the internal anatomy of the root canals visible, offering an economical and reliable pedagogical tool; however,the literature does not report standardized protocols to obtain a predictable dental clearance. Aim: obtain a standardized protocol for dental diaphonization as an educative model from the review of the literature and the realization of a pilot study. Materials and methods: A systematic search was made on databases Scopus and Medline, with the Mesh terms "root canal", "diaphonization", "clearing", "morphology" and, "anatomy", and an extraction table was structured wit h the most representative variables to establish the three diaphanization phases, a. Decalcification, 5% Nitric Acid, 10% Formic Acid (TBD-2) and 10% EDTA were evaluated, b. Dehydration, ascending Ethyl Alcohols were used, c. Clarification, Methyl Salicylate, a nd Immersion synthetic oil were evaluated. 54 teeth were selected, 36 without root canal treatment and 18 with root canal treatment, then they were distributed into two groups: Group A, Teeth without root canal treatment, and Group B, Teeth with root canal treatment. Each group was constituted of 18 subgroups defined in order of the decalcification agent type, moment of the contrast medium application, and clarification agent type. Results: Even though 5% Nitric Acid was the most corrosive agent, it allowed a better flow and accessibility for the contrast medium (Chinese ink) in teeth without root canal treatment. Likewise, 10% Formic Acid preserved the structure of the endodontic tooth. As a clarification agent, the Methyl Salicylate showed better visual results, achieving greater transparency. Conclusion: The development of a pilot study aimed to standardize diaphonization techniques in dentistry allows the structuring of educative protocols that permit knowing the great tooth anatomic variability and the comprehension as well as the analysis of the root canal treated teeth, contributing to a pedagogic tool for the root anatomy awareness. Using 10% Formic Acid on root canal-treated teeth and 5% Nitric Acid on root canal not treated teeth, with transparency achieved by using Methyl Salicylate, showed better visual results on anatomy and endodontic filling

Assessment of root canal anatomy of maxillary and mandibular canine teeth: a cone-beam computed tomography study / Evaluación de la anatomía del canal radicular de caninos maxilares y mandibulares: un estudio de tomografía computarizada de haz cónico

Abstract To investigate the root canal anatomy of permanent maxillary and mandibular canines in a Turkish subpopulation using cone beam computed tomography (CBCT). Retrospective CBCT data of 300 patients admitted to our clinic between 2016 and 2018 were screened and evaluated. A total of 235 patients, 100 males and 135 females, aged 14-76 years (mean age 37.27±13.40) were included in this study. A total of 191 (44,8%) maxillary canine teeth and 235 (55,2%) mandibular canine teeth were examined. The number of roots and root canal morphology according to Vertucci's classification, the presence of accessory canals, and the position of the apical foramen of the root were analyzed. The effect of gender and age on the incidence of root canal morphology was also investigated. The majority of the teeth had a Type I canal configuration in both maxillary canines (100%) and mandibular canines (92,8%). In the mandibular canines the other canal patterns found were Type III (6,8%), and Type II (0,4%). Apical foramen was centrally positioned in the majority of the teeth, 70,2% and 66,8% in maxillary and mandibular canines, respectively. The occurrence of two roots in mandibular canines was 3,8% and the root canal separation was found 53,8% and 46,2% in the middle and cervical third of the root, respectively. No significant statistical difference was observed effect of gender and age on the incidence of the root canal morphology and the position of the apical foramen. Due to the diverse morphology and the potential presence of a second canal for canine teeth among the Turkish subpopulation, dentists should perform endodontic treatments with greater care. CBCT is an accurate tool for the morphological assessment of the root canals.

Resumen Investigar la anatomía del conducto radicular de los caninos maxilares y mandibulares permanentes en una subpoblación turca utilizando la tomografía computarizada de haz cónico (CBCT). Se examinaron y evaluaron los datos CBCT retrospectivos de 300 pacientes ingresados en nuestra clínica entre 2016 y 2018. Un total de 235 pacientes, 100 hombres y 135 mujeres, de entre 14 y 76 años (edad media de 37,27±13,40) fueron incluidos en este estudio. Se examinaron un total de 191 (44,8%) dientes caninos maxilares y 235 (55,2%) dientes caninos mandibulares. Se analizó el número de raíces y la morfología del conducto radicular según la clasificación de Vertucci, la presencia de conductos accesorios y la posición del foramen apical de la raíz. También se investigó el efecto del sexo y la edad en la incidencia de la morfología del conducto radicular. La mayoría de los dientes tenían una configuración de conductos de tipo I tanto en los caninos maxilares (100%) como en los caninos mandibulares (92,8%). En los caninos mandibulares los otros patrones de conductos encontrados fueron el Tipo III (6,8%) y el Tipo II (0,4%). El foramen apical estaba situado en posición central en la mayoría de los dientes, 70,2% y 66,8% en los caninos maxilares y mandibulares, respectivamente. La ocurrencia de dos raíces en los caninos mandibulares es del 3,8% y la separación del conducto radicular se encontró en el tercio medio y cervical de la raíz en el 53,8% y el 46,2%, respectivamente. No se observó ninguna diferencia estadística significativa en el efecto del sexo y la edad sobre la incidencia de la morfología del conducto radicular y la posición del foramen apical. Debido a la diversa morfología y a la posible presencia de un segundo conducto en los dientes caninos entre la subpoblación turca, los odontólogos deberían realizar los tratamientos endodónticos con mayor cuidado. La CBCT es una herramienta precisa para la evaluación morfológica de los conductos radiculares.

An In Vitro Study to Assess the Root Canal Morphology of Human Primary Molars Using Computerised Tomography

Background: A virtuous consideration of root canal morphology is required. Complications all through and after endodontic therapy are frequently caused by variances in the anatomy of root canals in primary teeth. The goal of present study was to determine the number and shape of root canals in primary incisors and molars, as well as the pertinency of cone beam computerised tomography (CBCT) in doing so.Material & Methods:On a total of 60 primary molars and incisors with complete root length, CBCT was used to assess the number of roots, number of canals, width of root canal at cementoenamel junction and middle-third, length and angulations of roots. The information was statistically analysed. Results:The CBCT revealed that 13 percent of mandibular incisors had bifurcation of the root canal in the middle third, while 20% of mandibular molars had two canals in the distal root. The distobuccal root canal diameter of maxillary molars and the mesiolingual canal diameter of mandibular molars were determined to be the smallest.Conclusions:Cone beam computed tomography (CBCT) is a comparatively new and effective technology that can be used in conjunction with conventional radiography to examine variations in root canal morphology in primary teeth.

Root Canal Morphology of Primary Molars – A Cone Beam Computed Tomography (CBCT) Study

Objectives: To evaluate the root and canal morphology of primary maxillary and mandibular molars in an Indian population using cone?beam computed tomography (CBCT). Methods: A retrospective cross?sectional study was performed, where CBCT scans of children less than 10 years of age taken for valid diagnostic purposes previously were considered and images were analyzed. The number of roots, root canals, and variations in morphology were recorded. Left–right symmetry was also noted. Results: A total of 433 deciduous maxillary and mandibular primary molars were studied. It was observed that two separate roots with three separate canals were common in primary mandibular first molars, whereas two separate roots with two canals in each root were common in mandibular second primary molars. In primary maxillary molars, three separate roots with one canal each were the most common. Maxillary first molars (17.21%) and 17.35% second molars had fused distobuccal and palatal roots. It was observed that primary maxillary molars showed more left–right symmetry (86.7% in first molars and 82.7% in second molars) compared to primary mandibular molars (54.05% in first molars and 68% in second molars). Conclusions: It was concluded that in both primary maxillary first and second molars, three separate roots, a mesiobuccal root, a distobuccal root, and a palatal root with one canal in each root, were the most common. Two separate roots with three separate canals were the most common in primary mandibular first molars, whereas two separate roots with two canals each in both roots were more common in mandibular second primary molars.

In-depth morphological evaluation of tooth anatomic lengths with root canal configurations using cone beam computed tomography in North American population

Abstract Objective This study aimed to assess the association between tooth size and root canal morphology by using CBCT analysis. Methodology In this retrospective study, tooth anatomic lengths (crown and root lengths, buccolingual and mesiodistal dimensions) of 384 patients were assessed and correlated with Vertucci's root canal morphology classification. Data was analyzed for gender-related differences using the independent sample t-test, ANOVA, and the Pearson's correlation for a possible relation between anatomic lengths and canal morphology. Results The maxillary first and second premolars showed a greater predilection for Type IV and II variants, respectively, while the mandibular first premolar showed a greater predilection for Type II canal system. The root canal system of the mandibular second premolar showed maximal diversity (47% Type I, 30% Type II, and 20% Type III). The dimensions were greater in men regardless of tooth type. The most significant relation (p<0.05) between the anatomic size and canal morphology was observed in the maxillary first premolars, followed by the mandibular canines (buccolingual dimension) and the lower second premolars (crown length). Negative correlations existed between the crown length and the patient's age for the anterior teeth and mandibular second premolar (r=−0.2, p<0.01). Conclusions The most common canal formation for anterior teeth was the Type I. The anatomic lengths had the strongest influence on the canal configuration of the maxillary first premolar, with Type IV being the most common root canal system. The mandibular second premolars showed maximal diversity in the canal classification terms and had a significant correlation with their crown lengths. Clinical Relevance The complex relationship between the canal morphology and anatomic tooth sizes need meticulous awareness and recognition during endodontic procedures, in conjunction with the demographic variabilities.

Assessment of Mesial Canals Morphology of Mandibular First Molars Using CBCT: An In-vitro Study / Avaliação da morfologia dos canais mesiais dos primeiros molares inferiores usando TCCB: um estudo in vitro

Objective: The current study aimed to investigate the relationship between canal configuration, distance between mesiobuccal (MB) and mesiolingual (ML) orifices and the degree of canals curvature in the mesial root of permanent mandibular first molars in a sample of Sudanese population using cone-beam computed tomography (CBCT). Material and Methods: A total of 143 extracted mandibular first molars were processed and scanned with CBCT to determine the configuration of the mesial root canals according to the Vertucci classification. The interorificial distance and the degree of canal curvature in clinical (CV) and proximal (PV) views using Schneider technique were assessed. Results: The commonest canal configuration was type IV (53.1%). The interorificial distance was significantly shorter in type VI compared to other types (P < 0.05). Significant association was found for type IV between the MB and ML canal in the primary curvature regarding CV and PV, and for type II regarding PV in primary and secondary curvature (P < 0.05). In type IV the degree of secondary curvature of MB canal regarding PV, and in the ML canal in CV was significantly lower compared to other types (P < 0.05). Significant correlation was seen in PV of primary curvature in the MB for type VI (P < 0.05). Conclusion: The interorificial distance and secondary curvatures in CV for MB canal were found to be key factors for predicting root canal patterns in PV (AU)

Objetivo: O presente estudo teve como objetivo investigar a relação entre a configuração do canal, a distância entre os orifícios de entrada dos canais mesiovestibular (MB) e mesiolingual (ML) e o grau de curvatura dos canais na raiz mesial dos primeiros molares inferiores permanentes em uma amostra da população sudanesa usando tomografia computadorizada cone-beam(TCCB). Material and Methods: Um total de 143 primeiros molares inferiores extraídos foram processados e escaneados com TCCB para determinar a configuração dos canais radiculares mesiais de acordo com a classificação de Vertucci. A distância inter orificios e o grau de curvatura do canal nas vistas clínica (CV) (acredito que a tradução seja essa mesma, seria como uma foto intra oral clínica/perguntei a um endodontista, mas não soube me responder) e proximal (PV) usando a técnica de Schneider foram avaliados. Resultado: A configuração mais comum do canal foi do tipo IV (53,1%). A distância inter-orificios foi significativamente menor no tipo VI em comparação com outros tipos (P <0,05). Correlação significativa foi observada na PV da curvatura primária no MB para o tipo VI (P <0,05). Conclusão: A distância inter orifícios e as curvaturas secundárias na CV para o canal MB foram consideradas fatores-chave na predição dos padrões do canal radicular na PV (AU)

Cone-beam computed tomography study of C-shaped root canal of mandibular premolars / 口腔疾病防治

Objective@#To investigate the incidence and morphology of C-shaped root canals in mandibular premolars by cone-beam computed tomography (CBCT) imaging, which provides a reference for clinical diagnosis and treatment.@*Methods @#The CBCT scanning data of 964 mandibular first premolars and 907 mandibular second premolars in 508 cases were collected, and the root canal morphology, incidence of C-shaped root canals, bilateral symmetry and location of radicular grooves were analyzed.@*Results@#The incidence of C-shaped root canals in mandibular first premolars was 4.1% and that in mandibular second premolars was 0.6%. The incidence of C-shaped root canals of mandibular first premolars was significantly higher than that of mandibular second premolars (χ2=25.775, P < 0.001). The symmetrical ratio of C-shaped root canals in the mandibular first premolars was 29%. There were no symmetrical C-shaped root canals in the mandibular second premolars. There were significant differences in the distribution of the C-shaped root canal configuration in the root canal (P < 0.001). The C-shaped configuration mainly existed in the middle axial and apical level of the mandibular premolars. The C2 type was more common. No C-shape was found in the coronal level of the mandibular premolars. Vertucci I single tube type was the most common type of root canal for the mandibular premolars included in this study; the incidences were 81.7% and 98.3% for the mandibular first and second premolars, respectively, and the difference was statistically significant (χ2=140.544, P < 0.001). The other root canal types of mandibular first premolars were more than those of mandibular second premolars. The incidences of Vertucci Ⅱ, Ⅲ, Ⅳ, and Ⅴ and C-shaped root canals in mandibular first premolars were significantly higher than those in mandibular second premolars. C-shaped root canal mandibular premolars had radicular grooves, and most of them were located at the mesiolingual side.@*Conclusion@# The morphology of the C-shaped root canal in mandibular premolars was complicated. CBCT can provide direct and accurate imaging evidence for clinical diagnosis and treatment.

The prevalence of radix molaris in the mandibular first molars of a Saudi subpopulation based on cone-beam computed tomography

OBJECTIVES: The purpose of this study was to determine the incidence of radix molaris (RM) (entomolaris and paramolaris) in the mandibular first permanent molars of a sample Saudi Arabian subpopulation using cone-beam computed tomography (CBCT).MATERIALS AND METHODS: A total of 884 CBCT images of 427 male and 457 female Saudi citizens (age 16 to 70 years) were collected from the radiology department archives of 4 dental centers. A total of 450 CBCT images of 741 mature mandibular first molars that met the inclusion criteria were reviewed. The images were viewed at high resolution by 3 examiners and were analyzed with Planmeca Romexis software (version 5.2).RESULTS: Thirty-three (4.5%) mandibular first permanent molars had RM, mostly on the distal side. The incidence of radix entomolaris (EM) was 4.3%, while that of radix paramolaris was 0.3%. The RM roots had one canal and occurred more unilaterally. No significant difference in root configuration was found between males and females (p > 0.05). Types I and III EM root canal configurations were most common, while type B was the only RP configuration observed.CONCLUSIONS: The incidence of RM in the mandibular first molars of this Saudi subpopulation was 4.5%. Identification of the supernumerary root can avoid missing the canal associated with the root during root canal treatment.

Endodontic management of maxillary first molar with an anatomical variation of two palatal canals: A case report

An in-depth knowledge of the root canal anatomy is important for any successful root canal treatment; however, complexities exist within the root canal morphology. The maxillary first molar has variations in its root morphology and canal configurations. In literature, this variation is only observed in an estimated 1.12%-1.17%. One such case is described in this case report which provides the endodontic management of a left maxillary first molar with two palatal canals using loupes magnification.

Radix entomolaris: reporte de caso / Radix entomolaris: report of a case

Una de las variaciones anatómicas que pueden presentar los molares inferiores es una tercera raíz que ha sido denominada radix entomolaris o paramolaris dependiendo de su localización, ya sea lingual o vestibular respectivamente. Conocer las variaciones morfológicas de las piezas dentarias es un requisito fundamental para el éxito del tratamiento endodóntico. El objetivo de este artículo es la presentación de un caso clínico de una paciente con ambos primeros molares inferiores con presencia de radix entomolaris; en la pieza dentaria 4.6 se realizó tratamiento endodóntico y en 3.6 con una lesión endoperiodontal combinada verdadera se decidió su exodoncia (AU)

The application of three-dimensional reconstruction-based Micro-CT in the research of root canal treatment / 口腔疾病防治

@#Important guarantees of the success of root canal therapy include being familiar with the anatomical features of root canal system, good root canal preparation and complete root canal filling. With the development of medical imaging technology, three-dimensional reconstruction technology has been widely applied in root canal morphology, root canal preparation, root canal filling quality, root canal retreatment efficiency, three-dimensional finite elements and other related research. The reconstructed 3D images can be observed qualitatively and quantitatively from different angles and levels, which aid in the understanding of root canal anatomy and evaluation of the operation effect on all aspects of root canal therapy, providing important guiding significance for clinical operation. The application of 3D reconstruction technology based on micro-CT in the research of root canal anatomy, root canal preparation, root canal filling, root canal retreatment efficiency and three-dimensional finite element analysis are reviewed. The results of a literature review showed that the resolution of micro-CT is high. Furthermore, three-dimensional reconstruction can accurately display the fine anatomical morphology of a root canal, accurately measure the volume and morphological changes of root canal before and after root canal preparation, accurately measure the incidence and volume of the void after root canal filling and accurately calculate the volume changes of the root canal filling materials before and after root canal retreatment. Micro-CT is the gold standard for the morphological study of the root canal system and quality analysis of root canal preparation and filling. After three-dimensional reconstruction with micro-CT scans, a three-dimensional finite element model can be established to simulate the process of root canal therapy and stress analysis. This method can be used to analyze the stress distribution of root canal preparation instruments and the influence of root canal preparation on the stress distribution of tooth tissue and the root canal wall in the process of root canal filling. Then, suitable operation methods can be selected to prevent instrument breakage and root fracture. The application of three-dimensional reconstruction-based micro-CT is of great value in the evaluation of root canal morphology and treatment.

A case of maxillary second premolar with 3 teeth and 4 root canals and a literature review / 口腔疾病防治

Objective @#To explore the discovery and treatment of multiple root canals in the maxillary second premolar to provide a reference for root canal therapy.@*Methods @#A case of maxillary second premolar occlusal discomfort accompanied by cold and heat stimulation pain and spontaneous pain was analyzed retrospectively.@*Results@# In this case, the number of roots and root canals in the tooth was determined by CBCT to be three roots with four canals. Root canal therapy was performed with Ni-Ti endodontic files and thermoplastic gutta-percha via root optical microscopy. The clinical symptoms disappeared after the operation.@*Conclusion@#The maxillary second premolar root canal system is complex, and additional root canals can be found and located with CBCT and optical microscopy. High-quality root canal therapy was completed.

Root canal morphology of the mandibular first premolars in a Yucatecan population using cone beam computed tomography: an in vitro study / Morfología del conducto radicular de primeros premolares mandibulares en una población yucateca usando tomografía computarizada: estudio in vitro

A successful endodontic treatment requires knowledge of the internal configuration of dental root canals. Most of the people who live in Yucatan are of Maya origin, characterized by a Mongoloid dental pattern. Because of their ethnicity, variations are expected. The purpose of this investigation is to assess the morphological characteristics and variability of this population. One hundred and five extracted first mandibular premolars of Mexican Maya population were analyzed; the sample was obtained from the Oral Surgery Clinic in the School of Dentistry at the Autonomous University of Yucatan with written informed consent. Analyses were performed by means of Cone Beam Computed Tomography. Vertucci´s Type I was the most prevalent configuration with 51.4 %, but 41 cases (39.1 %) presented a radicular groove and a C-shaped canal configuration. Overall, we documented 1, 2, 3, and 4 root canals. Mandibular first premolars are very variable in the Yucatecan population. The variability and frequency of C-shape is similar to mandibular second molars confirming the importance of the ethnic background for the endodontic treatments.

El éxito en el tratamiento endodóntico requiere el conocimiento profundo de la configuración interna del sistema de conductos radiculares. La mayoría de las personas que viven en Yucatán son de origen Maya y poseen el patron dental Mongoloide; por lo tanto, se esperan variaciones debido a su etnicidad. El propósito de esta investigación fue evaluar las características morfológicas y la variabilidad del conducto radicular en la población yucateca. Se analizaron ciento cinco primeros premolars mandibulares extraídos de pacientes provenientes de una muestra Maya mexicana; la muestra fue obtenida de la Clínica de Cirugía Oral de la Facultad de Odontología de la Universidad Autónoma de Yucatán. Con consentimiendo informado escrito. Se utilizaron Tomografías Computarizadas para el análisis de la muestra. La configuración más prevalente fue la Tipo I de Vertucci con 51,4 %. Sin embargo, 41 de 105 casos (39,1 %) presentaron un surco radicular y la configuración en forma de "C". Se documentaron casos con 1, 2, 3 y 4 conductos radiculares. Los primeros premolares mandibulares de la población Yucateca son muy variables. La variabilidad y frecuencia de conductos en forma de "C" concuerda con estudios realizados en segundos molars mandibulares en esta zona confirmando la importancia del origen étnico de las poblaciones para los tratamientos endodónticos.

Evaluation of complex mesiobuccal root anatomy in maxillary first molar teeth / Evaluación de la anatomía de la raíz mesiobucal compleja en los primeros dientes molares maxilares

The objective of this study was to investigate the complex anatomy of mesiobuccal roots, supporting and complementing commonly applied clearing technique, using access cavity modification and the pulpal groove deepening method. Three hundred and ninety eight extracted intact human maxillary first molars were included in this study. Firstly, modified rhomboidal shape access cavities were prepared then, the developmental groove between the mesiobuccal and the palatal canals was deepened 1 mm with a round slow speed bur. Indian ink was injected into both the canal orifices of mesiobuccal roots and into the groove between mesiobuccal and palatal canals, using a 22 gauge syringe. Then the clearing technique was applied. The incidence of one canal was 30.90 %, two canals was 62.07 %, three canals was 7.03 %. In twenty five (6.28 %) of the mesiobuccal roots, 8 root canal types, which are not included in Vertucci's classification, were seen. All these root canal types had three root canals. The establishment of adequate access and deepening of the pulp chamber floor increased the probability of locating the third canal in the mesiobuccal root of maxillary first molars.

El objetivo de este estudio fue investigar la compleja anatomía de las raíces mesiovestibulares, apoyando y complementando la técnica de limpieza aplicada comúnmente, usando la modificación de la cavidad de acceso y el método de profundización del surco pulpar. En este estudio se incluyeron 398 primeros molares maxilares, extraídos intactos. Se prepararon las cavidades de acceso con la forma romboidal modificada, el surco de desarrollo entre los conductos mesiovestibular y palatino se profundizó 1 mm con una fresa redonda de velocidad lenta. Se inyectó tinta china en los forámenes del canal de las raíces mesiovestibulares y en el surco entre los conductos mesiovestibular y palatino utilizando una jeringa de calibre 22. Luego se aplicó la técnica de limpieza. La incidencia de un canal fue del 30,90 %, dos canales del 62,07 % y tres canales del 7,03 %. En 25 casos (6,28 %) de las raíces mesiobucales, se observaron 8 tipos de conductos radiculares, que no están incluidos en la clasificación de Vertucci. Todos estos tipos de conductos tenían tres conductos radiculares. La determinación de un acceso adecuado y la profundización del piso de la cámara de pulpa aumentó la probabilidad de localizar el tercer canal en la raíz mesiovestibular de los primeros molares superiores.

Maxillary first molar with a single buccal root / 实用口腔医学杂志

Maxillary first molar demonstrates considerable anatomic complexities and abnormalities with respect to the number of roots and root canals. The occurrence of maxillary first molar with a single buccal root is rarely reported in literature. This is a case report of maxillary first molar with a single buccal root and a palatal root,each of which has one canal.

Morphology of Maxillary First Molars Analyzed by Cone-Beam Computed Tomography among Malaysian: Variations in the Number of Roots and Canals and the Incidence of Fusion

Introduction: A few studies investigated the numerous potential endodontic uses of CBCT, including the examination of root canal morphology and presumed that CBCT was effective for the initial identification of such morphology; moreover CBCT is a reliable method for the detection of the MB2 canal when compared with the gold standard of physical sectioning of the specimen. The aim of this study was to identify the root and canal morphology of the maxillary first molars among Malaysians analysed by cone-beam computed tomography (CBCT) images. Materials and Methods: Maxillary first (n = 421) molars from Malaysian patients (n = 241) of Malay, Chinese and Indians inceptions were examined by two Endodontists using in vivo CBCT methods. The number and configuration of roots, the number of root canals, and the canal configuration according to Vertucci’s classification were determined. Results: Single roots were not found in maxillary first molars. The incidence of fused roots was 1.995% in the first molars between mesiobuccal and distobuccal roots. In (421) 3-rooted maxillary first molars, additional canals were found in 45.6% of the mesiobuccal (MB) roots and 0% of the distobuccal (DB) roots. Bilateral symmetry of the MB roots was found in 82.36% of the first molar. Only one tooth was found to have pulp stone inside the pulp chamber. Conclusions: The root and canal configuration of a Malaysian population showed different features from those of other populations. CBCT scans can enhance the understanding of root canal anatomy, with the potential of improving the outcome of endodontic treatment.

A study of root canal morphology in maxillary third molars using cone-beam computed tomography / 口腔疾病防治

Objective@#This study investigated root canal morphology in maxillary third molars by CBCT to provide an anatomical guideline for clinical treatment.@*Methods@#CBCT images of 397 maxillary third molars were collected. The root canal morphology was analysed, including the number of roots and the type of canals.@*Results @# In 397 maxillary third molars, three roots were the most frequently type, accounting for 43.07% and the fused root teeth were the second, accounting for 40.30%. For the root canal type, three canals were the most common, accounting for 47.86%, followed by single canal, accounting for 28.21%. According to the Vertucci root canal classification, 89.6% of the root canals were typeⅠ, the rest were typeⅡ, typeⅢ, type Ⅴ, and other types of root canals which were difficult to deal with in clinical treatment.@*Conclusion @#The root canal morphology of the maxillary third molar is various and the root canal system was complicated.

Cone beam- computed tomography as an indispensable tool in the management of radiculous premolar: a case report

Background: Internal anatomy of maxillary first premolars is particularly multifaceted on account of the variation in number of roots and canal configuration. Maxillary first premolars with 3 roots are called as small molar or "radiculous" because of their similar anatomy to the maxillary first molars. The most demanding step in endodontic treatment is identification and proper access to pulp canals of certain teeth with atypical canal configurations. Methods of identification of such premolars can be by various aides. Case Presentation: The present case describes the application of Cone Beam-Computed Tomography in the diagnosis of extra root with extra canal in a three rooted maxillary right first premolar. Conclusions: Proper knowledge of the anatomical variations is a must for an endodontist to make a treatment successful. Utilizing the latest technology along with the traditional concepts can surely rule out the inaccuracy in the treatment involved in such cases.

Maxillary first premolar with 3 root on both sides of a subjet:case report / 实用口腔医学杂志

The maxillary first premolar is a transitional tooth between incisors and molars. Most maxillary first premolars have 2 root canals. However, the bilateral maxillary first premolar with 3 roots and 3 canals has not been described. This article reports a rare case:The bilateral maxillary first premolar with 3 roots and 3 canals.