Method: Through a field, descriptive, observational and transversal study, a group of 140 upper third molars and 80 lower third molars were catalogued according to the number of cusps and coronal geometric shapes. They were photographed with standardized technique in the same position, focal distance and lighting for each projection, and the images were drawn at angles and lines present in the occlusal profiles using computerized graphic desing. They were reclassified according with the form determined in the graphical description and the data were analyzed statistically using percentages.
Result: The results showed that the upper third molars with tricuspid heart shape were predominant with 57% of occurrence. The prevalence observed in the lower third molars was five-cusp pentagonal form, which was found in 33% of the sample. Only 11% of upper third molars and 12% lower presented anomalous and unrecognizable forms.
Conclusion: The variability present in the coronal forms of specimens reflects patterns in different shapes, which are recognized more easily by morphometric analysis. The percentage predominance of one cusp type for each part of the sample was notorious and only a minority showed anomalous crowns.