Single-Implant Survival: More Than 30 Years of Clinical Experience

Purpose: The aim of this study was to report long-term clinical survival of single implants provided with turned and moderately rough surfaces in routine practice. Materials and Methods: All patients consecutively treated at a specialist center with single-crown implants from 1982 to 2013 were included. For all these patients, data on implant failure and last examination at the clinic were collected, and thereafter cumulative survival rates (CSR) were calculated for patients treated in the maxilla or mandible with turned or moderately rough surfaces, respectively. Results: In total, 2,417 patients (2,665 operations) were treated with 3,211 single implants during the inclusion period (31 years). Of these, 573 (615 operations, 754 implants) were followed up for at least 10 years. Overall proportions of patients followed up for 5 years up to 25 years decreased from 68.2% to 37.0% of treated patients. A higher follow-up compliance was observed for patients treated during the earlier period of inclusion. Patient CSR for 15 and 10 years for maxillary implant placement was 95.8% for turned surfaces and 98.5% for moderately rough surfaces, respectively. Corresponding patient CSR for 10 and 25 years for mandibles was 95.1% and 97.2%, respectively. No implant was reported as a failure after 10 years of follow-up. Conclusion: A significant number of patients can be expected to be lost to followup during long-term periods in routine practice. Single-implant treatment is an overall predictable treatment procedure over the long term, with a lower failure rate for implants with a moderately rough surface placed in the maxilla. This difference seems to be established already during the early phase of osseointegration.