Titanium implants for bone-anchored hearing aids--host reaction.

In a series of 31 prospectively followed patients equipped with bone-anchored hearing aids (BAHA), 7 titanium implants (19.4%) were lost in 6 patients after a median of 42 months (range: 27-78 months), often after visible resorption of bone around the superficial part of the implant. Expressed in a sample life table, no implants were lost during the first 2 years. After 3-4 years, the success rate dropped to about 85% and after 6-7 years to about 75%. Research that aims to define the factors which influence the extrusion rate is needed.