Root Morphology of First Permanent Molars Extracted from Adult Dental Patients of Similar Ethnicity in Dar-Es-Salaam, Tanzania.

Background: Root morphology of first permanent molars has been reported to be complex and associated with ethnicity, age, and gender. Objective: To assess the external and internal root morphology of first permanent molars extracted from dental patients of similar ethnicity in Dar es Salaam, Tanzania. Methodology: This descriptive cross-sectional study assessed the external and internal root morphology of first permanent molars extracted from adult patients attending dental clinics in Dar es Salaam. External morphology was visually assessed for root separation or fusion. Separated roots were assessed for the presence and direction of curvature using a graph paper with a drawn vertical and horizontal grid. Computed tomography scanning assessed the internal morphology of teeth embedded in wax blocks. Using transverse slice images at level of pulp floor, number and distance between canal orifices in a root were assessed. Data were analyzed descriptively. For associations, a p-value of <0.05% and 95% confidence intervals were used. Results: Of the 384 extracted teeth, 275 (71.6%) fulfilled the inclusion criteria. Majority, (64.2%) of mandibular molars were extracted from patients aged 18-40 years (70.6%) and females (57.6%). Three, (91.2%) and two, (98.0%) separated roots were observed in maxillary and mandibular molars, respectively. Distal curvature of maxillary mesiobuccal root (52.0%) was statistically significantly related to age. Mandibular mesial (83%) roots were curved buccal (p  > 0.05). Maxillary mesiobuccal and mandibular mesial roots showed higher proportion of two canal orifices with mean distance of 0.11-0.39 mm between orifices. Conclusion: The majority of maxillary and mandibular first permanent molars from Tanzanian adult dental patients had an external morphology of three and two separated roots with distal curvature of mesiobuccal roots of maxillary molars being statistically significantly related to age. The internal morphology of maxillary mesiobuccal and mandibular mesial roots showed higher proportion of two canal orifices with mean distance varying between 0.11 and 0.39 mm. Variations in root morphology were not related to sex.