Study of Genial Tubercles of Craniofacial Anomalies Individuals on Cone Beam Computed Tomography Scans.

Purpose: Genial tubercles (GTs) are bony protuberances on the lingual aspect of the mandible symphysis, where genioglossus and geniohyoid muscles are inserted. In the literature, few papers report their real dimensions. Cleft lip and palate are craniofacial anomalies involving the maxilla, but the anatomical structures of the mandible can be altered when these have associated with the cleft, some syndrome. This study aimed to evaluate the GTs of 30 individuals and to make their measurements in cone beam computed tomography examinations.

Methods: A sample of 30 individuals, 19 of them with cleft lip and palate, 6 individuals with Treacher Collins syndrome (TCS), and 5 individuals with Pierre Robin sequence, was used. The GTs were evaluated about the amount and the following measurements were performed: A--distance from the apex of the central incisors to GT, B--mandibular thickness in the region of GT, C-GT height, D-GT width, and E--distance from inferior border of mandible to GT.

Results: The individuals presented since the absence of GTs to 3. The TCS group had the highest average of the measurements A, D, and E with statistical difference (P = 0.006) (P = 0.011) and (P = 0.017), respectively. The Pierre Robin sequence group had the highest average measurement of B and C, but there was no statistical difference.

Conclusions: The difference in the measurements can be explained perhaps because individuals with TCS have glossoptosis and changes on retrognathic mandible, which would affect the position of the GT.