Microcomputed tomography analysis of particular autogenous bone graft in sinus augmentation at 5 months: differences on bone mineral density and 3D trabecular structure

This study investigated the effects of gender on the three-dimensional (3D) bone mineral density (BMD) and micromorphology of the trabeculae of matured autogenous bone grafts after sinus floor augmentation, and compared them to those of adjacent native bone. Ten bone biopsy samples were removed from the implant placement areas of patients who had received second-stage sinus floor augmentation, and analyzed by microcomputed tomography. BMD phantoms with two calcium hydroxyapatite densities (0.25 and 0.75 g/cm(3)) were used to determine the BMD of the grafted and native bone samples. The 3D structural parameters of the trabeculae, including percentage of bone volume (bone volume/tissue volume, BV/TV), trabecular thickness (Tb.Th), trabecular number, trabecular separation, trabecular pattern factor (Tb.Pf), and structure model index, were analyzed between males and females and between grafted bone and native bone. No significant gender-specific differences in BMD and 3D trabecular structure of either native or grafted bone were found (P > 0.05). Compared to the adjacent native bone, the autogenous grafted bone exhibited lower BV/TV and Tb.Th as well as a higher Tb.Pf (P < 0.05). Additionally, there was a weak positive correlation between the Tb.Th values of grafted and native bone (R (2) = 0.58). In the maxillary sinus, autogenous grafted bone exhibited lower BV/TV, Tb.Th, and trabecular connectivity than the adjacent native bone. No significant gender-specific differences were found for either the BMD or 3D trabecular structure of grafted bone. After bone remodeling, autogenous grafted bone revealed different 3D trabecular structure as compared to native bone.