Comparison of two different forms of bovine-derived hydroxyapatite in sinus augmentation and simultaneous implant placement: an experimental study.

PURPOSE: The aim of this study was to compare two different forms of bovine-derived hydroxyapatite (HA) in sinus augmentation and simultaneous implant placement.

MATERIALS AND

METHODS

The schneiderian membranes of 12 domestic pigs were elevated bilaterally through an extraoral approach. One sinus of each pig was grafted with bovine-derived granular HA (GHA) and the other was grafted with bovine-derived spongiosa block HA (BHA) (Unilab Surgibone). One dental implant was placed simultaneously into each grafted sinus. Animals were sacrificed after 6 months of healing. Primary implant stability (ISQi) and secondary implant stability (ISQf) were measured by resonance frequency analysis. Undecalcified sections were prepared for histomorphometric analysis.

RESULTS

Mean ISQi values for implants placed in sinuses grafted with BHA and GHA were 68.8 +/- 5.0 and 68.2 +/- 3.7, respectively (P > .05). The mean ISQf value for implants in GHA increased to 72.0 +/- 5.1 and for implants in BHA decreased to 52.3 +/- 8.8 (P < .01). There was a statistically significant difference between ISQi and ISQf values for implants placed in BHA (P = .03) and GHA (P = .037). Mean bone-implant contact (BIC) in residual bone was 61.3% +/- 2.1% for BHA and 61.2% +/- 1.7% for GHA (P > .05). In augmented bone, mean BIC percentages were 20.6% +/- 2.1% and 35.6% +/- 1.8% for BHA and GHA, respectively (P = .002). Mean percentages of connective tissue were 61.9% +/- 9.5% and 48.4% +/- 10.7% (P = .036), new bone formation percentages were 12.8% +/- 5.5% and 27.9% +/- 4.6% (P = .012), and percentages of graft material around the implants were 25.3% +/- 5.8% and 22.4% +/- 6.2% (P > .05) for BHA and GHA, respectively.

CONCLUSION

The form of graft material affects the osseointegration of implants in sinus augmentation and simultaneous implant placement.