Three-dimensional radiographic assessment of the mandibular interforaminal donor site in different vertical facial growth types.

PURPOSE:To assess volumetrically, the impact of vertical facial growth types (VFGT) on the mandibular interforaminal region as a potential bone donor site. MATERIAL AND METHODS:60 cone beam computed tomography (CBCT) scans of adult individuals were classified in three groups according to their SN-GoGn angle: hypodivergent group (hG) (N=20), normodivergent group (NG) (N=19) and hyperdivergent group (HG) (N=21). Total harvestable bone volume (TBV), cortico-cancellous bone volume (CBV-cBV), and cortical bone surface (CBS) were evaluated. ANOVA test followed by Tukey post hoc tests were used to compare the mean continuous outcomes according to their VFGT. RESULTS:The whole sample showed a mean TBV of 1376.32±541.01mm3, CBV of 468.52±121.54mm3 and cBV of 908.73±474.71mm3. The mean CBS amounted to 782.58±146.80mm2. The comparison between the groups stated a significantly different mean TBV and cBV (-p-value<0.001). The mean CBS was significantly different (-p-value=0.015): the smallest for the NG, but not significantly different (-p-value<0.001): the highest for the HG, intermediate for the NG and the smallest for the hG. CONCLUSION:Hypodivergent individuals have the thickest cancellous bone suitable for an onlay bone graft, while hyperdivergent individuals have the thinnest bone ideal for a 3D grafting approach.