SOME CHARACTERISTICS OF THE RIDGE MUCOSA BEFORE AND AFTER IMPLANT INSTALLATION - A PROSPECTIVE-STUDY IN HUMANS

The aim of the present investigation was to study some tissue characte ristics of the ridge mucosa before and after implant installation. 9 p artially edentulous patients were included in the study. At the time o f fixture installation, 1 recipient site in each patient was selected for soft tissue biopsy. Abutment connection and restorative therapy we re performed after 3-6 months. When the implants had been in function for about 6 months, a soft tissue sample was obtained from the keratin ized peri-implant mucosa at the 1 implant site from which the first bi opsy was obtained. Each biopsy was divided into 1 mesial and 1 distal portion. The mesial tissue portion was fixed in a buffered fixative an d embedded in EPON(R). Sections were produced, stained in PAS and tolu idine blue and used for histometric and morphometric analyses. The dis tal portion of the biopsies were embedded, snap frozen in liquid nitro gen and stored in a freezer at -70 degrees C. From each tissue portion , 15 sections were prepared in a cryostat and exposed to immunohistoch emical staining. A panel of monoclonal antibodies was used and the avi din-biotin method for staining was applied. The sections were examined morphometrically. Both tissues harbored a well keratinized oral epith elium and a connective tissue, the composition of which was close to i dentical in terms of collagen, cells and vascular structures. The peri -implant mucosa, however, also included a junctional epithelium which evidently allowed the penetration of products from the oral cavity. As a consequence, the periimplant mucosa in comparison to the masticator y mucosa was found to contain significantly enhanced numbers of differ ent inflammatory cells.