Root canal morphology of native Tanzanian permanent mandibular molar teeth

INTRODUCTION: Research has shown variations in morphology of root canals to differ amongst ethnic groups. We aimed to investigate the root morphology and canal configuration of permanent mandibular molars in a native Tanzanian population. METHODS: 146 first and 85 second mandibular molars were collected from Tanzanian patients. After removal of the pulp tissues and staining using Methylene blue ink from the canal system, the teeth were decalcified and rendered clear using 98% methyl salicylate. The teeth were then examined under magnification of 10X for: number of roots, tooth length, number of canals, location of apical foramen, presence of an apical delta and canal configuration using Vertucci's classification. RESULTS: All mandibular molars had two separate roots. The mean tooth length for mandibular 1(st) and 2(nd)molars were 21.7 mm and 20.5mm, respectively, with no statistically significant difference in mean tooth length between males and females. All the mesial roots 1st and 2(nd) mandibular molars possessed two root canals, while 40.4% and 54.1% of the distal roots of 1(st) and 2(nd) molars, respectively, had two canals. The majority of the examined teeth had their apical foramen located centrally, with an apical delta present in the distal root of one-second molar. Root canal configuration types commonly reported were Type II in the mesial and Type I in the distal roots of the mandibular 1(st) molar; while the 2(nd) molar had, respectively, root types II / IV and type I. CONCLUSION: There were observed variations in the morphology of root canals in a Tanzanian population. Caution is advised to clinicians when performing root canal treatment.