Preclinical application of recombinant human bone morphogenetic protein 2 on bone substitutes for vertical bone augmentation: A systematic review and meta-analysis

Statement of problem: Recombinant human bone morphogenetic protein 2 (rhBMP-2) has been introduced to clinical practice because of its osteoinductive capacity. However, the evidence of its efficacy in vertical bone augmentation procedures is not clear. Purpose: The purpose of this systematic review and meta-analysis was to investigate the efficacy of rhBMP-2 in vertical bone augmentation and to establish whether its addition in preclinical experiments (animal studies) would be sufficient to justify further clinical and histometric studies. Material and methods: An electronic search of 3 databases, PubMed/MEDLINE, EMBASE, and Web of Science, and a manual search of the reference list of relevant studies were performed. Only randomized controlled trials regarding animal studies comparing the efficacy of bone grafts supplemented with and without rhBMP-2 in vertical bone augmentation procedures were included and reviewed. Results: Nine studies were included. The results of the meta-analysis showed that the pooled weighted mean difference (WMD) of the percentage of newly formed bone was 9.97% (95% confidence interval [CI]=−0.79% to 20.72%; P=.070), the WMD of the percentage of residual materials was −21.31% (95% CI=−70.62% to 28.00%; P=.400), the WMD of the augmented bone height was 1.70 mm (95% CI=−0.23 to 3.63 mm; P=.080), the WMD of the augmented bone height for studies with space-providing barriers was 1.00 mm (95% CI=0.43 to 1.57 mm; P<.001), and the WMD of the percentage of regenerated tissue was 17.07% (95% CI=8.52% to 25.62%; P<.001). Conclusions: The application of rhBMP-2 in bone substitutes did not enhance new bone formation and residual graft resorption in vertical bone augmentation procedures. Tissue regeneration and the augmented bone height were significantly improved by the additional use of BMP-2.