Long-Term Follow-up of a Wide-Diameter Bone-Anchored Hearing Implant: 10-Year Experience on Stability, Survival, and Tolerability of an Implant-Abutment Combination

Objective: To compare stability, survival, and soft tissue reactions between a wide-diameter (test) and previous-generation small-diameter (control) bone-anchored hearing implant and to ascertain the safety of loading the test implant 3 weeks after surgery, at a long-term follow-up of 10 years.

Study Design: This study is a continuation of two previously completed, multicenter, randomized, controlled trials and consisted of one to two additional follow-up visits until 10 years after surgery.

Patients: Fifty-one of the 72 participants from the previous trials were included. Patients received a test or control implant. All control implants were loaded 6 weeks after surgery (group A). Test implants were loaded 3 (group B) or 6 weeks (group C) after surgery.

Results: The test implant showed significantly higher implant stability quotient (ISQ) values than the control implant throughout the 10-year follow-up. At 10 years, the mean ISQ-high values for both implants were higher than at the first follow-up visit. No significant differences in change of ISQ-high from baseline to 10 years were noticed between both implants and loading groups. Soft tissue reactions were rarely seen. At 10-year follow-up, no patients presented with adverse soft tissue reactions. Excluding explantations, the implant survival rate was 78.6% (group A), 100% (group B), and 90.0% (group C).

Conclusions: The test implant showed superior mean ISQ values and significantly better implant survival throughout 10-year follow-up. In addition, the current study concludes that it is safe to load the test implant at 3 weeks after surgery, as long-term results show high ISQ values and good implant survival.