Stability, Survival, and Tolerability of a Novel Baha Implant System: Six-Month Data From a Multicenter Clinical Investigation

Objective: Determination of the difference in implant stability between a novel Baha implant system (test) and the previous-generation implant system (control). Methods: In an open, randomized, prospective multicenter clinical investigation, 77 adult patients with Baha implants were included. Test and control implants were randomly assigned in proportions of 2:1. Implant stability quotient (ISQ) values were recorded using resonance frequency analysis at the time of implantation and at 10 days, at 4, 6, 8, and 12 weeks, and at 6 months after surgery. Skin reactions were evaluated according to the Holgers classification. Sound processor fitting was performed from 6 weeks after implantation. Results: Significantly higher mean ISQ values, measured between 0 and 6 months, were obtained for test compared to control implants (70.4 versus 65.4, p < 0.0001). Statistically significant differences were obtained for the study population as a whole and for the subgroup of patients loaded at 6 +/- 1 weeks after implant surgery (63.6% of patients). Up to 12 weeks, Holgers rates were comparable, whereas at 6 months, more skin reactions (Grades 1 and 2) were observed in the control implant group. No reduction in mean ISQ values was observed after implant loading. Conclusion: The test implant showed higher mean ISQ values at the time of placement and over time. The level of osseointegration reached with the implants in adults as early as 6 weeks after implantation was sufficient to support the sound processor. The test implant system is expected to provide additional benefits related to the improvement of the degree of osseointegration, especially for patients with thin or compromised bone.