Evaluation of the Human Recombinant Bone Morphogenetic Protein-2 Combined With Anorganic Bovine Bone in Maxillary Sinus Augmentation: A Prospective Study

The purpose was to evaluate the effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with anorganic bovine bone (ABB) on bone regeneration following maxillary sinus augmentation. Sixteen patients (9 men, 7 women; mean age: 59.6 y) who required sinus floor elevation for implant placement in the maxilla were randomly assigned to 2 groups. The ABB group received ABB, while the ABB+BMP group received ABB with rhBMP-2 for maxillary sinus augmentation. Five months later, bone core biopsies were harvested during implant placement using a trephine bur. Each specimen was analyzed using μ-CT to measure the bone volume (BV/TV), bone mineral density (BMD), trabecular thickness (TbTh), and trabecular separation (TbSp). Histologic evaluation was performed to calculate the new bone formation ratio (NBF). The μ-CT analysis revealed higher mean values of BV/TV (50.61±13.86%), BMD (0.646±0.059 g/cm3), and TbTh (0.097±0.050 mm) in the ABB+BMP group than in the ABB group (43.92±9.77%, 0.632±0.053 g/cm3, and 0.096±0.027 mm, respectively), while TbSp was lower. Although these differences did not reach statistical significance due to the limited sample size, the overall numerical trends indicated a potential for denser trabecular structure and greater bone mineralization in the ABB+BMP group. The mean NBF was higher in the ABB+BMP group (17.08±7.62%) compared with the ABB group (14.03±5.96%). Within the limitations of this underpowered study, no statistically significant differences were observed between the groups. However, the numerical trends suggest that rhBMP-2 has the potential to support qualitative improvement in bone maturation and trabecular structure within grafted sinuses. rhBMP-2 may serve as an effective adjunct to ABB, but further adequately powered trials are required to confirm this efficacy.