Dental implants have revolutionized tooth replacement, offering a reliable and effective solution for missing teeth. A new study now provides insights into the longevity of single-tooth implants over an astonishing 38–40 years, demonstrating their long-term success despite some challenges with crown survival.
The study followed a group of 16 patients who received single-tooth implants at the Brånemark Clinic in Gothenburg, Sweden, between 1982 and 1985. These patients, aged 14 to 48 at the time of treatment, were some of the earliest recipients of single implants. Over the decades, they were periodically examined to assess implant survival and potential complications.
Of the original 16 patients, almost all were re-evaluated close to 40 years after treatment. The results showed a high cumulative survival rate (CSR) of 95.6% for the implants, confirming their durability. The study’s findings align with shorter-term studies, which reported similar CSRs over 14 to 22 years.
Implant Survival vs. Crown Longevity
While the implants themselves exhibited exceptional longevity, the crowns placed on them did not fare as well. The survival rate of implant-supported crowns in this study was just 60.9%, significantly lower than previous reports of 80-89% over shorter follow-up periods. This indicates that while the implant fixtures remain functional for decades, crown replacements may be necessary due to wear, esthetic concerns, or mechanical failures.
One reason for the high crown replacement rate in this study may be the initial design choices. The early crowns were often made of resin and were later upgraded to ceramic restorations for better esthetics and durability. A systematic review also found common technical complications over five years, such as screw loosening (8.8%) and veneer fractures (3.5%), highlighting the need for careful crown maintenance.
Beyond mechanical durability, the study also assessed biological complications, including peri-implantitis and marginal bone loss. Despite some deep probing depths (>6mm in 22% of cases), no implants in this study showed signs of severe peri-implantitis, and bone levels remained remarkably stable. Interestingly, many implants even exhibited bone gain over time, a rare and promising finding.
These stable outcomes were achieved despite the use of machined-surface implants, which were standard at the time. Modern implants with roughened surfaces are designed for faster osseointegration, but this study suggests that even early designs can deliver excellent long-term results when placed and maintained properly.
This research offers key takeaways for clinicians today. While single-tooth implants demonstrate outstanding long-term survival, the crowns may require periodic replacement. Understanding factors that contribute to implant longevity—such as patient selection, careful surgical techniques, and proper prosthetic design—remains crucial for optimizing treatment outcomes.
Additionally, patient compliance and regular follow-ups are essential. Many of the original study participants traveled long distances to be re-evaluated, demonstrating their commitment to the study and potentially benefiting from consistent professional care over the years.
As millions of patients worldwide receive single-tooth implants, long-term studies like this one provide invaluable guidance on what to expect decades after treatment. While individual crown restorations may wear out, the underlying implants appear to stand the test of time—offering patients a lasting solution for tooth replacement.
Journal Reference:
- Sargon Barkarmo, Jan Kowar. Outcome of Single Dental Implants Over 38–40 Years: A Long‐Term Follow‐Up Study. Clinical Implant Dentistry and Related Research, 2025; 27 (1) DOI: 10.1111/cid.13443
Comments