Two-stage Lateral Maxillary Sinus Lift using Autogenous Bone and β-Tricalcium Phosphate: Clinical and Histomorphometric Evaluation

Background: To assess the clinical and histomorphometric data of the new bone tissue from a mixture of autologous bone and β-tricalcium phosphate. Materials and methods: A total of 72 two-stage sinus lift were performed in 54 patients during 2007 to 2010. The autologous bone was harvested from the mandibular ramus and mixed with the β-tricalcium phosphate Poresorb® TCP sized 1-2 mm. The materials were used in a proportion ranged between 1:1 and 1:3. After the healing period a total of 119 implants were placed and 10 samples of the regenerated bone were collected for the histomorphometric analysis. CBCT or panoramic X-rays were performed presurgically, before the implant placement, six months after implant placement and then yearly to evaluate the bone formation and marginal bone loss. The implant success rate was determined using the Albrektsson et al. Criteria. Results: The mean of the residual bone was 4.07 mm ± 1.87 mm. The bone gain in the sinus was 11.91 mm ± 2.80 mm. The implant success rate was 94.95%. The histomorphometric measurements on the biopsies showed a bone area mean of 39.7 ± 9.71%. The residual allograft area was 16.21 ± 8.78%. The connective tissue was 44.16 ± 5.85%. Conclusion: Within the limit of this study, the osteoconductive β-tricalcium phosphate associated with autologous bone is a viable grafting material for sinus lift procedures. The use of composite grafts can help to reduce the morbidity and aggressivity of the bone harvesting. Keywords: Sinus lift; Bone regeneration; Dental implants; β-tricalcium phosphate; Bone graft; Bone atrophy