The Effect of Bone Morphogenetic Protein-2 (BMP-2) on Volumetric and Histometric Outcomes for Peri-Implant Defects in the Animal Model: A Systematic Review and Meta-Analysis

Purpose: To study the effect of BMP-2 on the volumetric and histometric changes in peri-implant defect treatments in animal models. Materials and Methods: An electronic search of four databases and a manual search of peer-reviewed journals for relevant articles were performed. Animal studies with data that compared the volumetric and/or histometric outcomes of peri-implant defect treatment with and without the use of BMP-2 were included. Meta-analyses were performed to analyze the weighted mean difference (WMD) and confidence interval (CI) for the recorded variables. Results: After completing the search process, 21 randomized controlled trials were included. The results of the meta-analyses showed that the WMD of bone-to-implant contact (%BIC) with 4 to 8 weeks and 12 to 24 weeks of follow-up was 15.50% (95% CI = 3.28% to 27.72%, P = .01) and 16.17% (95% CI = 11.17% to 21.16%, P < .00001), respectively, favoring the BMP-2 group. The WMD for the percentage of defect fill with 4 to 8 weeks and 12 to 24 weeks of follow-up was 15.88% (95% CI = 3.90% to 27.86%, P = .009) and 10.48% (95% CI = 0.95% to 20.02%, P = .03), respectively, favoring the BMP-2 group. The WMD for the vertical bone gain with 8 to 16 weeks of follow-up was 1.63 mm (95% CI = 0.58 to 2.67 mm, P = .002), also favoring the BMP-2 group. Conclusion: This review demonstrated that the use of BMP-2 in treating peri-implant defects showed better clinical and histometric outcomes than defects not treated with BMP-2 in animal models.