Two- Versus Four-Narrow-Implant-Retained Dentures With Immediate-Loaded Anterior Implants: 9 Years Randomized Clinical Trial.

INTRODUCTION: In many clinical cases, anatomical conditions such as an atrophied alveolar ridge do not allow insertion of normal diameter implants. At this point, narrow dental implants may provide an effective option to avoid complex surgical treatments. The aim of this trial was to evaluate long-term survival, prosthetic and biological complications, and OHRQoL for two-piece narrow dental implants supporting overdentures with Locator-attachments. METHODS: Twenty-five patients with edentulous mandibles received four narrow dental implants and retained dentures with Locator attachments. Following successful implantation, immediate loading of anterior implants with Locator attachments was performed, while posterior implants underwent a conventional healing procedure. Follow-up examinations included documentation of implant and denture-related complications, modified gingiva index, modified plaque index, OHIP-G, and radiographic measurements of bone loss. RESULTS: Up to 9 years after restoration, 18 patients with 72 implants were available for the follow-up. During the observation period, one implant was lost in the immediate loading group. Implant survival was 98% and 100%. The outcomes of mPI and mGI for the 18 patients hardly differed between the groups. During the observation period, 136 prosthetic complications occurred. Scores for the different OHIP-G domains at the last follow-ups were stable over the years. CONCLUSIONS: Throughout an extended period of observation, we found stable implant survival rates, good maintenance of oral hygiene, and manageable prosthetic complications. The OHRQoL was satisfying over the years, suggesting that this treatment option could be favorable for older individuals. TRIAL REGISTRATION: https://drks.de/search/en/trial/DRKS00005497.