Prevalence of Root Canal Configuration Types Based on Number of Canals at the Apical Third of Mandibular First Molar Roots
Journal of Clinical and Diagnostic Research
Experimental design: A pilot study was conducted and based on its result using G-Power software sample size was calculated. Sample calculation was performed using 95% confidence intervals. Approximately 250 samples were needed. Mandibular first molars extracted from individuals above 30 years of age were collected without gender bias. Teeth that demonstrated fully-formed roots and intact external root morphology were selected and those with open ABSTRACT Introduction: Mandibular first molars
... lar first molars are the earliest permanent posterior teeth to erupt and are, hence, most frequently in need of endodontic treatment. Success of endodontic treatment depends on three-dimensional obturation at apical third. Single canal with simple tubular configurations are easy to obturate than multiple canals involving merging or splitting of canals at apical third. There are no studies evaluating root canal configuration at apical third. Aim: The aim of the present study was to investigate the prevalence of root canal configuration types based on number of canals at the apical third of mandibular first molar roots. Materials and Methods: This experimental study evaluated a total of 250 mandibular first molars by clearing technique. The number of roots and canals were identified and canal configurations at the apical third were classified according to Vertucci and supplemental classifications. Chi-square test was applied to evaluate prevalence of root canal configuration types based on number of canals at the apical third of mandibular first molar roots. Results: A majority of the mandibular first molars (90.8%) were two-rooted. Three roots were observed in 6% of samples, four roots in 2% and fusion between roots in 1.2%. In the mesial root, two canals (48.4%) in the apical third was most prevalent, followed by one (25.8%), three (14.7%) and four (11.1%) canals. In the distal root, one canal in the apical third (74.2%) was the most prevalent finding followed by two (21.8%), four (2.8%) and three (1.2%) canals. The difference in prevalence of canal numbers in the apical third of the mesial and distal roots was statistically significant. The mesial root exhibited more variability than the distal root in canal configuration types. In the third root of three rooted molars, canal configuration was simple. In all the fused roots, C-shaped configuration was observed. Conclusion: Merging and splitting of root canals resulting in complex configuration although less prevalent were observed at apical third roots of mandibular first molar.