Abstract:
BACKGROUND: Several studies have reported certain bone morphogenic proteins (BMPs) to have
positive effects on bone generation. Although some investigators have studied the effects of human recombinant
BMP (rhBMP-2) in sinus augmentation in sheep, none of these studies looked at the placement of implants
at the time of sinus augmentation. Furthermore, no literature could be found to report on the impact
that different implant systems, as well as the positioning of the implants had on bone formation if rhBMP-2
was utilized in sinus-lift procedures. PURPOSE: The aim of this study was to compare sinus augmentation with
rhBMP-2 on a poly-D, L-lactic-co-glycolic acid gelatine (PLPG) sponge with sinus augmentation with autologous
pelvic cancellous bone in the maxillary sinus during the placement of different dental implants. MATERIALS AND METHODS: Nine adult female sheep were submitted to bilateral sinus-floor elevation. In one side (test group) the
sinus lift was performed with rhBMP-2 on a PLPG-sponge, while the contralateral side served as the control by
using cancellous bone from the iliac crest. Three different implants (Bra¨nemark , 3i and Straumann ) were
inserted either simultaneously with the sinus augmentation or as a two staged procedure 6 weeks later. The animals
were sacrificed at 6 and 12 weeks for histological and histomorphometrical evaluations during which boneto-
implant contact (BIC) and bone density (BD) were evaluated. RESULTS: BD and BIC were significantly
higher at 12 weeks in the test group if the implants were placed at the time of the sinus lift (p\0.05). No difference
was observed between the different implant systems or positions. CONCLUSIONS: The use of rhBMP-2
with PLPG-sponge increased BIC as well as BD in the augmented sinuses if compared to autologous
bone. Different implant systems and positions of the implants had no effect on BIC or BD. 2010 European
Association for Cranio-Maxillo-Facial Surgery.
