Micro-Computed Tomographic Analysis of Maxxillary Sinus Augmentation with Autogenous Bone

Objectives: Micro-computed tomographic (micro-CT) were used to analyze the bone volume, density and trabecular structure of the grafted bone after the treatmet of sinus augmentation filled with autogenous bone. Methods: After the surgery sinus augmentation with autogenous bone (harvested from ilium and chin) and 5 to 6 months of the maturation of healing period, seven cylindrical biopsy of grafted bones were taken at implant locations from seven patients and analyzed by the micro-CT (Skyscan1076, SkyScan, Aartselaar, Belgium) with 17.8 ìm of resolution of micro-CT images to study the (a) bone mineral density (BMD, g/cm3), (b) percent bone volume BV/TV (%), (c) trabecular thickness Tb.Th (pixel, 1 pixel=18ìm ), (d) trabecular number Tb.N (1/pixel), and (e) trabecular pattern factor Tb.Pf (1/pixel). Software CTAn (SkyScan) was used to create the three- dimensional model of biopsy as well as to calculate the BMD, BV/TV, Tb.Th, Tb.N, and Tb.Pf of native bone and grafted bone. All data were statistically analyzed with Wilicoxon's signed rank test. Results: The median data of BMD in native bone is 0.292 and in grafted bone is 0.1 ( p=0.22), In BV/TV, The median data in native bone is 28.15 and in grafted bone's median is 14.49 (p=0.81), . The median data of Tb.Th, Tb. N, and Tb.Pf related to trabecular bone structure are 13.15 , 0.019 and 0.064 in native bone as well as 7.69 (p<0.05), 0.019 (p=0.47) and 0.1754(p=0.38) in grafted bone. Conclusions: BMD, BV/TV, Tb.N, and Tb.Pf shows a huge variation except Tb.Th, which exhibited that even throughout the maturation of healing period, the trabecular thickness of autogenous grafted bone is still thinner than that of native bone. Acknowledgement: This research was supported by National Science Council (NSC 98-2815-C-039-036-B) and China Medical University in Taiwan.