Titanium implants permanently penetrating human skin.

Titanium implants were allowed to penetrate the skin of the upper arm of 8 human volunteers in an attempt to investigate the conditions for a permanent implant transcutaneous passage. If a construction was used that restricted the skin movements around the implant no inflammatory or other adverse soft tissue effects were noted for follow-up periods of 7-25 months. In another clinical investigation of 4 patients with hearing impairment, titanium implants were firmly anchored in the temporal bone, allowed to penetrate the skin and external hearing aids were directly attached. These transcutaneous implants are still functioning without any problems at a follow-up period of 38-50 months. The reason for the favorable results achieved are thought to be connected to the material (non-alloyed titanium), the design of the implant and a minimally traumatising surgery. The results of this paper are pointing to new treatment possibilities using external prostheses anchored to the skeleton via skin penetrating mechanical connections as e.g. stable and permanent episthesis attachment in cases of severe facial injuries. A clinical trial along these lines is presently being performed.