A 5-Year follow-up of 80 implants in 44 patients placed immediately after the lateral trap-door window procedure to accomplish maxillary sinus elevation without bone grafting

Purpose: The present study was performed to evaluate the 5-year status of immediately placed implants subjected to maxillary sinus elevation without grafting. Materials and Methods: Implants were placed in 2004 and 2005. A minimum of 3 mm of residual bone height (RBH) was required. All implants were placed with a sinus elevation performed through a lateral approach by the trap-door, open-window method without placement of any grafting material. Regular follow-up included oral hygiene instruction, periodontal charting, panoramic radiographs, and cone beam computed tomographic scans. The gained bone height (GBH) in the sinus, peri-implant sulcus depth, and marginal bone loss were analyzed statistically. Results: Forty-four patients (26 men, 18 women) with an average age of 58 years received 80 implants, which were followed for 5 years after prosthesis delivery. No patients developed sinusitis or other complications leading to implant loss. The average RBH was 5.06 ± 1.51 mm and the average intrasinus implant length was 7.77 ± 1.69 mm. Survival rates for the implants were 100% after 2 and 5 years. Average GBH was 7.24 ± 1.83 mm at 2 years (range, 3 to 12 mm) and 7.44 ± 1.94 mm at 5 years (P > .05). The average peri-implant sulcus depths were 2.5 ± 0.4 mm at 2 years and 3.1 ± 0.5 mm at 5 years (P < .05). The mean peri-implant marginal bone loss was 1.3 ± 0.3 mm at 2 years and 2.1 ± 0.5 mm at 5 years (P < .05). Conclusions: New bone formation in the sinus was confirmed, and good survival of implants with maxillary sinus elevation by the lateral approach without grafting was observed after 5 years. Attention should be focused on oral hygiene maintenance to ensure peri-implant gingival health.