Survival and Success Rates of Dental Implants Placed Using Osteotome Sinus Floor Elevation Without Added Bone Grafting: A Retrospective Study with a Follow-up of up to 10 Years.

This retrospective study with a follow-up period of 4 months to 10 years evaluated survival, success, and complication rates of implants placed using osteotome sinus floor elevation (OSFE) without added bone grafting. A total of 926 implants were placed, including 530 short implants (6 mm to 8.5 mm) and 209 implants in low residual bone height (RBH) (< 5 mm). Bone levels were evaluated at approximately 3 months and at 1, 3, and 5 years, and in some cases up to 10 years after implants were placed. The implant survival rate was 98.3% at the 5-year follow-up. Twelve of the 926 implants failed (6 preprosthetic, 6 postprosthetic). The success rate was 95.4% at a threshold of less than 1 mm of bone loss for combined systems (Straumann; Nobel Biocare). Short implant survival and success rates were statistically comparable to conventional-length implants. Low-RBH implants had a lower but acceptable survival rate of 95.7%. Adverse events were rare, with one case of infection and zero cases of vertigo reported. The findings of this study indicate that implant placement with OSFE without added bone graft is highly successful, even when short implants are used in low RBH.

Trifactorial classification system for osteotome sinus floor elevation based on an observational retrospective analysis of 926 implants followed up to 10 years.

OBJECTIVE: A novel osteotome trifactorial classification system is proposed for transcrestal osteotome-mediated sinus floor elevation (OSFE) sites that includes residual bone height (RBH), sinus floor anatomy (contour), and multiple versus single sites OSFE (tenting). METHOD AND MATERIALS: An analysis of RBH, contour, and tenting was retrospectively applied to a cohort of 926 implants placed using OSFE without added bone graft and followed up to 10 years. RBH was divided into three groups: high (RBH > 6 mm), mid (RBH = 4.1 to 6 mm), and low (RBH = 2 to 4 mm). The sinus "contour" was divided into four groups: flat, concave, angle, and septa. For "tenting", single versus multiple adjacent OSFE sites were compared. RESULTS: The prevalence of flat sinus floors increased as RBH decreased. RBH was a significant predictor of failure with rates as follows: low- RBH = 5.1%, mid-RBH = 1.5%, and high-RBH = 0.4%. Flat sinus floors and single sites as compared to multiple sites had higher observed failure rates but neither achieved statistical significance; however, the power of the study was limited by low numbers of failures. CONCLUSION: The osteotome trifactorial classification system as proposed can assist planning OSFE cases and may allow better comparison of future OSFE studies.