Histomorphometric Analysis of Maxillary Sinus Grafts: A Randomized Controlled Study

The purpose of this clinical investigation was to evaluate and compare the degree of new bone formation through histomorphometric analysis following maxillary sinus grafts (MSG) using three different bone graft materials. Thirty-one MSG were performed using a lateral window approach for patients who required implant placement in posterior maxilla. Each sinus was randomly selected to receive one of three bone graft materials; Group A: anorganic bovine bone mineral (ABBM) [Bio-Oss®], Group B: anorganic equine bone mineral (AEBM) [Equimatrix®], or Group C: mineralized cancellous bone allograft (MCBA) [OSSIF-i sem™]. A total of 28 bone cores were obtained at a mean time of 9.1 months following MSG and used for the histomorphometric analysis. The quality of bone was also estimated (Lekholm & Zarb 1985) during biopsy using a trephine bur. Histologically, newly formed bone showed close contact to the residual graft materials and interconnected the bone particles in all groups. Histomorphometric analysis revealed statistically significant differences in the percentage of vital bone (VB%) among three groups (Kruskal Wallis, P = .001). The observed VB% was significantly lower [P= .004] in Group A (10.9 ± 8.9%) and also lower [P = .001] in Group B (9.1 ± 5.9%) as compared to Group C (32.0 ± 12.4%). No significant difference in VB% was noted between Group A and Group B [P = 1.0]. Within the confines of this study, a statistically significant difference in new bone formation was noted among the three graft materials at a mean follow-up period of 9.1 months following MSG. The MCBA (OSSIF-i sem™) group revealed significantly greater new bone formation when compared to the ABBM (Bio-Oss®) and AEBM (Equimatrix®) groups. The AEBM showed comparable histomorphometric results in all parameters (VB%, RBM%, CT) when compared to ABBM. Bone quality was greater in ABBA and AEBM groups in comparison to the MCBA group indicating the greater VB% does not directly translate to improved bone quality.