Objective: The aim of this randomized-controlled clinical trial was to evaluate the long-term outcome of implants placed in bone augmented with a xenogenic bone substitute material and a collagen membrane with or without the addition of recombinant human bone morphogenetic protein-2 (rhBMP-2).
Material and methods: Eleven patients received a total of 34 implants placed into sites exhibiting lateral bone defects. In a split mouth design, the defects were randomly treated with the graft material and the collagen membrane either with (test) or without (control) rhBMP-2. The patients were examined 3 and 5 years after insertion of the prosthetic restoration. Student's paired t-test was performed to detect differences between the two groups.
Results: The survival rate at 3 and 5 years was 100% for both groups. The peri-implant soft tissues were stable and healthy without any difference between the two groups. The prosthetic reevaluation demonstrated four loose prosthetic screws during the first 3 years and seven ceramic chippings after 3 and 5 years. The mean distance between the first bone to implant contact to implant abutment junction at 3 years was 1.37 mm (test), 1.22 mm (control), and 1.38 mm (test), and 1.23 mm (control) at 5 years. The difference of <0.2 mm between test and control implants was not statistically significant. The mean change of the marginal bone level between baseline and 5 years ranged from -0.07 mm (mesial, test), -0.11 mm (distal, test), -0.03 mm (mesial, control), to +0.13 mm (distal, control). No statistically significant differences were observed between test and control sites.
Conclusion: Implants placed in bone augmented with and without rhBMP-2 revealed excellent clinical and radiological outcomes after 3 and 5 years.