Method: An descriptive, observational, cross-sectional study of 60 upper third molars and 26 lower third molars multirooted was made. The teeth were photographed with standardized technique, in the same focal distance and lighting for each projection. Proximal and vestibular view of each specimen was drawn and graphics traced on two longitudinal axes: coronal and root. It was cataloged combined configurations among convergence, divergence, and presence or absence of curvature for each root and then classified into subgroups. Alternately, root angulation was measured and ranked in ranges. Finally, the data was tabulated and analyzed statistically using percentages.
Result: In the upper third molar, the proximal views showed predominance of divergent and straight roots configuration, which were presented in 68% of the buccal roots and 36% of the palatal roots. In assessing the vestibular projection, the more manifested subgroup had distally curved mesial roots and mesially curved distal roots, by 33% of the sample. Simultaneously, the lower teeth showed mesial roots with distal curvature, in 84% of the sample. Minor and similar percentages had appeared between remaining subgroups. In the proximal and buccal views of the upper third molars the most common angles ranged from 0 to 36 degrees with an average percentage of 79%.
Conclusion: It was found great diversity of combinations between the variables, with increased tendency to uniformity in the lower teeth. A larger sample in future studies will be useful to validate this results.