Although titanium dental implants are characterized by great biocompatibility, both electrochemical and galvanic corrosion may take place in the oral environment, even in the cases of full osseointegration of implants. The aim of the study was to evaluate processes occurring in the gingival mucous membrane collected from dental implants after a period of healing. In the gingival tissues in contact with implants fully integrated with the bone, infiltrations composed of subpopulations of T lymphocytes (CD45R0 and CD25) and Langerhans cells (S-100 positive) were found. The presence of immunologically competent cells in the infiltrations indicated that the titanium implant was recognized by the host’s immune system. The lack of clinical symptoms of hypersensitivity may suggest local tolerance to a correctly healed intraosseous dental implant.

18.2.2013