Loading of osseointegrated implants for bone conduction hearing at 3 weeks: 3-year stability, survival, and tolerability

The objective of this study was to ascertain the long-term safety of loading osseointegrated implants for bone conduction hearing 3 weeks post-surgery. Thirty consecutive adult patients were implanted with the Baha BI300 (Cochlear Bone Anchored Solutions) in our tertiary referral center. Implants were loaded with the sound processor 3 weeks post-surgery. Follow-up examinations were performed at 10 days; 3, 4, 6, 8, and 12 weeks; 6 months; and 1, 2, and 3 years after implant surgery. At each follow-up visit, implant stability quotient (ISQ) values were recorded by means of resonance frequency analysis, and soft tissue status was evaluated according to Holgers' classification. ISQ trends, implant survival, and soft tissue reactions were compared to a population of 52 patients with the same type of implants loaded from 6 weeks post-surgery as part of another study. Subjective benefit was measured by means of the Glasgow Benefit Inventory (GBI). After an initial dip in ISQ at 10 days after implantation, a gradually increasing trend in ISQ was found until 6 months in both populations, after which ISQ values remained above baseline values. Implant survival was 97 % in the study population and 96 % in the comparison population. Clinically relevant soft tissue reactions were found in 0.9 % (study population) and 1.7 % (comparison population) of all visits. Patients reported subjective benefit; the mean GBI score was 22.8. In conclusion, loading these implants at 3 weeks post-surgery is safe based on the current study, as long-term results show high ISQ values and good implant survival and tolerability.