Controlled Clinical Trial on Bone-anchored Hearing Implants and a Surgical Technique With Soft-tissue Preservation.

Abstract

To compare the clinical and audiological outcomes after linear incision with soft-tissue preservation and standard linear incision with soft-tissue reduction for placement of percutaneous bone-anchored hearing implants. Clinical trial with historical control-group from a previous randomized controlled trial. Tertiary referral center. Twenty-five patients were enrolled in a prospective cohort of bone-anchored hearing implant placement with linear incision and tissue preservation with a follow-up of 6 months. The control-group consisted of 25 patients from a previous randomized controlled trial in the same tertiary referral center. All sound processors were fitted 3 weeks after surgery. Numbness around the abutment, length of surgery, soft-tissue reactions according to Holgers' classification, Patient and Observer Scar Assessment Scale, implant loss, Implant Stability Quotient, and audiological outcome. Tissue preservation resulted in better results on sensibility (mean percentage correct responses 98% [SD 4.4] versus 89% [SD 15.0], p = 0.003), on the Patient and Observer Scar Assessment Scale (mean observer score 15.3 [SD 4.3] versus 19.4 [SD 6.3], p = 0.006), and shorter total surgery time (mean 24.6 min [SD 6.2] versus 31.9 min [SD 6.5], p < 0.001). More adverse soft-tissue reactions as measured by the Holgers classification were observed in the test-group (n = 7 [28%] versus n = 1 [4%], p = 0.049). For Implant Stability Quotient and audiology the study did not provide evidence that tissue preservation is better or worse compared with tissue reduction. Tissue preservation compared with tissue reduction leads to a generally favorable clinical outcome, comparable audiology results, and significantly shorter surgery time. Longer follow-up is warranted to conclude on the increased adverse soft-tissue reactions after 6 months.