Subantral Augmentation With Mineralized Cortical Bone Allograft Material: Clinical, Histological, and Histomorphometric Analyses and Graft Volume Assessments.

PURPOSE: The aim of this study was to clinically and histologically evaluate the effect of using mineralized cortical bone allograft in sinus lift augmentation and to 3-dimensionally quantify volumetric changes in maxillary sinuses augmented over a 2-year period. MATERIALS AND METHODS: Eleven patients affected with less than 3 mm of residual ridge were enrolled in the study. After sinus grafting with a mineralized bone allograft, the site was covered with a collagen wound dressing. During implant placement 4 months later, a biopsy was obtained for histological and histomorphometry evaluations. Bone volume changes were also evaluated. RESULTS: Biopsies showed mature cancellous bone with a predominantly lamellar structure. The well-vascularized intertrabecular spaces were filled with connective tissue and bone marrow. Histomorphometry evaluations revealed a mean 43.76 +/- 1.47% of bone marrow, 40.16 +/- 1.35% of mineralized bone and 16.59 +/- 0.55% of woven bone. The mean of residual particles was 0.47 +/- 0.01%. Volumetric measurements showed a mean volume of grafted material 16.24 +/- 1.55 cm at T0, 14.48 +/- 1.48 cm at T1, and 13.06 +/- 1.39 cm at T2. The mean volume retraction was 10.83% of the initial total volume at (T0-T1) and 9.8% at (T1-T2). CONCLUSIONS: The clinical and histological results indicated that mineralized cortical bone allograft promoted de novo bone formation and can be used for sinus lift procedure.