Successful loading of a bone-anchored hearing implant at two weeks after surgery: randomized trial of two surgical methods and detailed stability measurements.

OBJECTIVE: To assess early implant stability of a bone-anchored hearing implant in detail; safety of loading the implant 2 weeks after surgery; and whether surgical methods influence stability. STUDY
DESIGN: Single-center, randomized, nonblinded study using balanced randomization (1:1).
SETTING: Tertiary referral center in the Central Denmark Region. PATIENTS: Forty-seven adults with normal skin and bone quality. INTERVENTION: Implantation of the BAHA BIA300 system with randomization to a dermatome technique with soft tissue removal or linear incision with no soft tissue reduction. MAIN OUTCOME MEASURES: Implant Stability Quotient (ISQ) at 0, 3, 7, 10, 14, and 21 days and 1, 3, 6, and 12 months postoperatively. OTHER OUTCOME MEASURES: Implant loss.
RESULTS: Forty-nine patients were randomized (linear incision, 25; dermatome, 24). Forty-seven patients were analyzed (linear incision, 25; dermatome, 22). Mean ISQ value was 59.5 at implantation, increasing to 60.5 at 14 days. No stability dip was observed in the early osseointegration period. After loading at 14 days, stability was increasing with a nonsignificant ISQ-dip at 21 days. At 1-year follow-up, mean ISQ was 65.78 (linear incision) and 65.77 (dermatome) (mean difference, 0.010; 95% confidence interval, -2.17 to 2.19). One patient operated on with the dermatome technique had transplant necrosis. No implants were lost.
CONCLUSION: In the study population comprising healthy adults with estimated normal bone quality, early implant stability showed no initial stability dip and the implant was safely loaded 2 weeks after surgery. The surgical methods had no influence on implant stability.

RCT Entities:   Population Interventions Outcomes