Experience with the longer (8.5 mm) abutment for Bone-Anchored Hearing Aid

Use of the longer (8.5 mm) abutment for a Bone-Anchored Hearing Aid has been helpful for a certain group of patients. The most common reason for its use is soft tissue problems with tissue overgrowth interfering with device function. The longer abutment has been used in our institution, a tertiary referral center, on a named patient basis since 2002, and more than 100 patients have received it.

This paper will review this subgroup of patients and describe their demographics. Comorbidity, smoking history, graft failure, infection, and index of deprivation will be looked at as contributing factors for this group with soft tissue problems.

We identified 111 patients who had longer abutments ordered for them, and a retrospective case review was performed.

Eighty-one patients required soft tissue reduction surgery because of overgrowth, and all but one (80/81 [98.8%]) of these patients required no further surgery after having their 5.5-mm abutment changed to the 8.5-mm version. One patient underwent further surgery 10 months after the longer abutment was inserted but has been problem-free for 16 months since then. Length of follow-up ranged from 6 months to 5 years after converting to the longer abutment.

We have found the longer abutment to be very successful for the small proportion of patients with troublesome soft tissue overgrowth. We would advocate its use when topical management and surgical intervention have failed to control the skin reaction.