Permanent, skin penetrating, bone-anchored titanium implants. A clinical study of host-reaction in bone and soft tissue.

In 12 patients with a skin penetrating retroauricular titanium-implant (Brånemark) the reaction in bone and soft tissue was studied. Observation time was 6 to 36 months. All implants were "osseointegrated", as assessed by repeated manual test, X-ray examination and 99mTC-scintigraphy. Soft tissue reactions appeared to be slight and clinically insignificant. However, all patients produced crusts around the abutment. When the abutment was removed varying degrees of inflammatory reaction in the skin penetration could be observed in most patients. A theory for the development and cause of the soft tissue reactions is proposed and changes in the operative procedure and the design of the abutment to reduce the host reaction are suggested. It is stressed that the clinical significance of this host reaction is uncertain and above all has to be weighed against the important benefits this implant system offers to a severely handicapped group of patients.