Long-term results of implants and implant-supported prostheses under systematic supportive implant therapy: A retrospective 25-year study.

BACKGROUND Long-term data (>10 years) concerning the survival and success rates of implants and implant-supported prostheses are scarce. PURPOSE The present investigation represents one of the first studies on dental implants covering an observational period of 25 years. MATERIALS AND METHODS This study presents the results obtained in 26 patients with 75 implants who participated over a 23- to 28-year period in a supportive implant therapy (SIT) program at a private dental practice. We extracted existing data from the patients' files (pocket depths [PDs], bleeding on probing [BoP], radiographic peri-implant bone loss, and survival rates of the implant-supported prostheses). RESULTS After 25 years, the SIT-compliant patients' implants had a survival rate of 95% (prostheses: 88%). The mean peri-implant probing depth was 3.69 mm (median: 3.33; SD: 1.06; range: 2-8.33). The mean peri-implant bone level was 1.84 mm (median: 1.82; SD: 1.20; range: -0.97-5.2). Finally, the prevalence (moment of last consultation) and incidence (during the entire observational period) of peri-implantitis were 7% and 30%, respectively. CONCLUSIONS Under SIT conditions, clinicians may expect survival rates for implant-supported prostheses of >80%. Most implants (60%) did not develop signs of peri-implantitis over a 25-year period.