Long-term stable vertical bone regeneration after sinus floor elevation and simultaneous implant placement with and without grafting.

BACKGROUND: Less invasive surgical approaches to regenerate bone intra-sinus and allow long-term functional implant stability are needed.

PURPOSE: To evaluate long-term vertical bone regeneration after sinus floor elevation and simultaneous implant placement with and without bone grafting.

METHODS: Vertical bone gains (VBG) post-sinus elevation, with and without grafting, were evaluated in thirty individuals presenting an average residual bone height (RBH) of 4.2 mm using a standardized digital technique. Measurements were taken preoperatively, and at an average of 64.6 months follow-up. Clinically, peri-implant tissues were assessed for pocket formation and presence of inflammation to evaluate established success criteria.

RESULTS: Overall, RBH averaged 4.2 ± 1.1 mm (range: 1.8-5.8) and VBG 7.7 ± 1.6 mm (range: 6.0-12.9). Mean difference of 7.6 mm between vertical bone heights (VBH) at augmented implants sites and initial RBH, 11.8 versus 4.2 mm, (P < .0001, CI95%: 6.9-8.2) was statistically significant. RBH averaged 4.5 ± 0.8 mm and 3.8 ± 1.2 (P = .07) and VBG 6.8 ± 0.5 and 8.5 ± 1.9 mm (P = .003, CI95%: 0.6-2.7), for nongrafted and grafted individuals, respectively. The grafting group received an average graft volume of 0.35 ± 0.1 cc (range: 0.25-0.5) per implant site. Long-term follow-ups average 64.6 months (range: 36-144) and all implants met the success criteria. VBG ≥ 7 mm were 7.3 times more likely to develop on grafted sites (OR = 7.3, P = 0.02, CI95%: 1.2-46.2).

CONCLUSION: None to negligible amounts of grafting material are required to regenerate substantial amounts of autogenous bone into atrophic sinus cavities after simultaneous implant placement. The regenerated VBH seems stable for functional implant stability long-term. Implant success rates were 100% at an average of 64.6 months.