Electron microscopic observations on the soft tissue around clinical long-term percutaneous titanium implants

Percutaneous implants of titanium ad modum Brånemark have been in clinical use in the head and neck since 1977. The incidence of adverse reactions is low. In a previous study we have demonstrated the presence of inflammatory cells in the subcutaneous connective tissue surrounding the implants and this increased exposure to exogenous antigens was suggested to be compensated by a barrier of inflammatory cells in the soft tissue. To get further information on the nature of the tissue-implant contact, in the present study we have examined the structure of the tissue close to the percutaneous implant using transmission electron microscopy. We could not see evidence for an attachment of the epithelium to the implant, nor between the connective tissue and the implant. Retrieved implants were also analysed and we did not find any organized tissue remaining on the implants.