Dental implants treatment outcomes in patient under active therapy with alendronate: 3-year follow-up results of a multicenter prospective observational study

Objective: To evaluate the 3-year clinical and radiographic data of fixed implant-supported dental prosthesis delivered to patients having taken alendronate 35–70 mg weekly for at least 3 years before implant placement. Materials and Methods: Forty consecutive patients treated with oral bisphosphonates and requiring an implant-supported restoration were recruited in two private centers between January 2008 and December 2011. Implants were inserted through minimally invasive approach under antibacterial and antibiotic treatment, 6 months after alendronate administration stopping. After 4 months of submerged healing, implants underwent prosthetic loading. Hygiene maintenance and clinical assessments were scheduled every 4 months for 3 years. Outcome measures were the following: implant and prosthetic success, survival rates, any observed clinical complications, marginal bone remodeling, probing pocket depth and bleeding-on-probing. Results: At the end of the study, eight patients dropped out. The final sample size resulted in 32 consecutive partially or fully edentulous patients (32 females; mean age 64.6 years) with 98 submerged implants. In only one patient, maxillary implant failed during healing period. No prosthesis failed during the entire follow-up, and no major complications were recorded. Implant and prostheses success resulted in an overall survival rate of 98, 98% and 100%, respectively. Three-year mean marginal bone loss was 1.35 ± 0.21 (CI 95% 1.24–1.38). Successful soft tissue parameters were found around all implants. Conclusions: Oral bisphosphonate therapy did not appear to significantly affect implant survival and success in case of accurate treatment time selection, minimally invasive surgical approach and constant follow-up. Further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm these results.