RESUMO
OBJECTIVE: To evaluate and compare several anatomical parameters of mandibular first premolars from individuals from different Latin American countries using micro-computed tomography. DESIGN: Five hundred extracted mandibular first premolars from Brazilian, Argentinian, Chilean, Colombian, and Ecuadorian individuals were scanned using micro-computed tomography (n = 100 teeth/country). Root canal configurations were classified according to established parameters. Analyses also included: canal volume and surface area, structure model index, distances from the apical foramen to the root apex or the cementoenamel junction, major/minor apical canal diameters, canal orifice shape, and prevalence of ramifications. RESULTS: A single root was the most common anatomy in all countries (range, 97%-100%). Vertucci's type-I canal was the most frequent configuration (range, 36%-66%), followed by C-shaped and type-V canals. The oval-shaped canal orifice was the most predominant in all countries (range, 34%-58%), followed by the circular shape (range, 16%-47%). C-shaped canals occurred in all subpopulations (range, 14%-26%), always associated with radicular grooves. Ranges for canal ramifications were as follows: accessory canals, 36%-73%; lateral canals, 4%-12%; and apical delta, 4%-14% of the teeth. Many anatomic parameters differed significantly between countries (P < .05). CONCLUSIONS: Vertucci's types-I and -V, and C-shaped canals were the most prevalent configurations in the subpopulations investigated. Accessory canals and several complex anatomies were found, with some significantly different frequencies between countries.
Assuntos
Mandíbula , Raiz Dentária , Humanos , Microtomografia por Raio-X/métodos , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , BrasilRESUMO
OBJECTIVE: To evaluate cone-beam computed tomography images in an Argentine population in order to determine the presence of mandibular premolars with C-shaped canal system and classify them. METHODS: 697 images were observed, 170 of them fulfilling the selection criteria. Once established the presence of a C-shaped canal system, premolars were classified using Fan's criteria. Data description was made by frequencies and percentages rates, with a 95% confidence interval according to the score method. Comparisons were assessed by means of the Chi-square test with a significance level equal to 5%. RESULTS: Of 269 first premolars, 27 teeth showed C-shaped canal system, i.e. 10%, and of 231 second premolars, 4 presented C-shaped canal system, i.e. 2%. Out of 17 patients presenting first premolars in both sides, 6 showed a bilateral C-shaped canal system pattern and 11 did not present this condition. When the condition was unilateral (nâ¯=â¯15), 7 patients showed C-shaped canal in the tooth 3.4 and 8 patients showed C-shaped canal in the tooth 4.4. The second premolars showed C-shaped canals unilaterally. Along the canal, configuration variations at the three-thirds have been observed for the first and second mandibular premolars. CONCLUSION: The C-shaped canal system pattern prevalence in mandibular first and second premolars was estimated for the first time in an Argentine population, in vivo. The present report contributes to the epidemiological understanding of the anatomical variable of the inner dental configuration and its extrapolation to the clinical practice.
Assuntos
Dente Pré-Molar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar , Raiz Dentária , Argentina , Cavidade Pulpar/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagemRESUMO
AIM: To describe morphometric aspects of the internal anatomy of C-shaped mandibular premolars from a Brazilian subpopulation using micro-CT analysis. METHODOLOGY: First mandibular premolars with radicular grooves (n = 123) were scanned using a micro-computed tomography system. After cross-section analysis, 83 specimens were identified with a C-shaped canal and selected for micro-CT analysis. Number and location of canals according to Vertucci's classification, distances between anatomic landmarks, occurrence of apical deltas, furcation canals, prevalence of C-shaped cross-sections at five levels as well as 2-dimensional analysis (Area, perimeter, roundness, aspect ratio, major and minor diameters) were performed for the more prevalent anatomical features. Data were compared statistically using Kruskal-Wallis tests (α = 0.05). RESULTS: The more prevalent anatomical types according to Vertucci's classification were Type I (13%), III (8%), V (37%) and VII (2%). Mean distances from the furcation to the cemento-enamel junction were in the range of 5.36-5.65 mm. Apical deltas and furcation canals were present in 36 (43%) and 27 (33%) specimens, respectively. C-shaped cross-sections were more prevalent at the middle (56%) and apical middle levels (81%). Overall, significant differences were found in the 2-dimensional analyses between single canals at the apical third and buccal and lingual canals of Vertucci's V classification (P < 0.05). CONCLUSIONS: In this Brazilian subpopulation, C-shaped canal configuration of the root canal system was found in 67% of extracted first mandibular premolars with radicular grooves. Vertucci's types I and V were the most prevalent anatomical variations. C-shaped cross-sections were more prevalent in the middle third, and the presence of apical deltas was the most common feature in the apical third.