Use of autogenous bone and beta-tricalcium phosphate in maxillary sinus lifting: histomorphometric study and immunohistochemical assessment of RUNX2 and VEGF.

The aim of this study was to compare the use of beta-tricalcium phosphate (beta-TCP) (chronOS) with autogenous bone grafts alone in maxillary sinus elevation surgery. The test samples were beta-TCP alone, beta-TCP mixed with autogenous bone grafts (1:1), and autogenous bone grafts alone. Twelve maxillary sinuses were grafted with beta-TCP (group 1), nine with beta-TCP+autogenous bone graft (group 2), and 12 with autogenous bone graft (group 3). After 6 months, biopsies were obtained concurrent to the placement of dental implants; these were subjected to histomorphometric analysis and immunohistochemical analysis for runt-related transcription factor 2 (RUNX2) and vascular endothelial growth factor (VEGF). The average bone formation in group 1 was 46.3+/-11.6% in the pristine bone region, 47.6+/-9.9% in the intermediate region, and 44.8+/-22.1% in the apical region; in group 2, values were 35.0+/-15.8%, 32.5+/-13.7%, and 32.8+/-16.0%, respectively; in group 3, values were 43.1+/-16.0%, 31.0+/-13.0%, and 46.1+/-16.3%, respectively. Immunostaining of samples in group 2 showed high cellular activity and immature bone; this differed from groups 1 and 3, in which mature bone was demonstrated. Thus, this study showed that beta-TCP presents the same behaviour as autogenous bone graft, which makes it a good bone substitute.