Factors affecting changes in sinus graft height between and above the placed implants

Objective. The aim of this study was to compare the radiographic dimensional changes of sinus graft height above and between placed implants, and evaluate the factors effecting these changes with 2 different grafting materials and both combination. Study design. The study group comprised 42 patients (50 sinus augmentation procedures). Four consecutive panoramic radiographs were evaluated for changes in sinus graft height between and above the placed implants. Factors that may influence graft height reduction were evaluated. Results. The mean percentage of autogenous bone height reduction was 23% between implants and 13% above the implants. Bovine xenograft showed a mean of 6.5% graft height reduction between implants and 0% above implants. The only 2 parameters that correlated with reduction of graft height above and between the implants were time elapsed from surgery and the type of bone graft. Autogenous bone graft presented significantly more reduction (P=.022), whereas anorganic bovine bone graft had only minor or no changes in height. Conclusion. The most important factor influencing reduction in vertical bone height on the time axis, following sinus augmentation is the grafting material, followed by the presence of a functional implant. Anorganic bovine bone was found superior in graft height maintenance in an up to 10 years of follow-up. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;111:e6-e11)