Primary bone augmentation leads to equally stable marginal tissue conditions comparing the use of xenograft blocks infused with BMP-2 and autogenous bone blocks: A 3D analysis after 3 years

Abstract

Objectives To test whether or not primary bone augmentation using xenograft blocks infused with BMP-2 or autogenous bone blocks lead to similar results regarding the implant survival and 3D marginal soft tissue contours. Methods Twenty-four patients with an insufficient ridge width for implant placement in need of primary augmentation were randomly assigned to either a block of deproteinized bovine bone mineral infused with rhBMP-2 (BMP) or an intraorally harvested block of autogenous bone (ABB). At 4 months, 1-4 dental implants were placed in the regenerated area. After crown insertion and at 3 years, peri-implant tissue parameters, two- and three-dimensional radiographic parameters, and soft tissue contour changes were evaluated. Explorative mixed model analyses were performed. The level of significance was set at 5%. Results At the 3-year follow-up, 23 patients with 40 implants were evaluated. The implant survival rate was 100% in both groups. At baseline, the marginal hard tissue levels amounted to -0.4 +/- 0.8 mm (mean +/- standard deviation) in the BMP group and -0.7 +/- 1.0 mm in the ABB group. At 3 years, these values were -0.2 +/- 0.4 mm (BMP) and -0.6 +/- 1.0 mm (ABB). At baseline, the thickness of the buccal hard tissue at the level of the implant shoulder measured 1.1 +/- 1.1 mm (BMP) and 1.4 +/- 1.0 mm (ABB). At 3 years, it measured 0.9 +/- 0.9 mm (BMP) and 0.7 +/- 0.6 mm (ABB). Conclusions The present study demonstrated excellent implant survival rates and stable marginal hard tissue levels in both augmentation groups, 3 years after crown insertion. In addition, the clinical stability of soft and hard tissues was demonstrated in both groups.