Bone-anchored hearing aids improve hearing for patients for whom conventional behind-the-ear aids are problematic. However, uptake of bone-anchored hearing aids is low and it is important to understand why this is the case.

A narrative review was conducted. Studies examining why people accept or decline bone-anchored hearing aids and satisfaction levels of people with bone-anchored hearing aids were reviewed.

Reasons for declining bone-anchored hearing aids included limited perceived benefits, concerns about surgery, aesthetic concerns and treatment cost. No studies providing in-depth analysis of the reasons for declining or accepting bone-anchored hearing aids were identified. Studies of patient satisfaction showed that most participants reported benefits with bone-anchored hearing aids. However, most studies used cross-sectional and/or retrospective designs and only included people with bone-anchored hearing aids.

Important avenues for further research are in-depth qualitative research designed to fully understand the decision-making process for bone-anchored hearing aids and rigorous quantitative research comparing satisfaction of people who receive bone-anchored hearing aids with those who receive alternative (or no) treatments.

Bone-anchored hearing aids are well established, implanted devices. We present two patients who suffered mixed hearing loss and who underwent titanium implant placement in the temporal bone to enable attachment of bone-anchored hearing aids. Osseointegration is necessary for such implants to function. We report these two cases to highlight how such osseointegration may be disrupted.

Attached tissue from the explanted or removed titanium implants was examined by transmission electron microscopy and histopathological analysis.

Attached tissue from both implants showed the presence of keratinocytes at the titanium implant and living bone interface. This was confirmed by histopathological analysis. In one case, there was frank keratinocyte proliferation, which had led to osseointegration failure; in the other case, such proliferation was present but not so advanced.

These findings suggest that, in the cases reported, keratinocytes implanted between the titanium and the living bone, leading to disruption of osseointegration.