INVITRO ATTACHMENT OF HUMAN GINGIVAL FIBROBLASTS TO ENDOSSEOUS IMPLANT MATERIALS

IN RECENT YEARS, THE FOCUS of dental implant research has been the nat ure of the bone-implant interface associated with osseointegration, ye t the transgingival portion of endosseous dental implants has received little attention. The purpose of this study was to determine the atta chment of human gingival fibroblasts to three different implant materi als: commercially pure titanium, non-porous hydroxyapatite, and porous hydroxyapatite. Cell attachment was quantified by radiolabeling gingi val fibroblasts with tritiated thymidine and counting attached cells b y liquid scintillation following incubation for periods of 20, 40, and 60 minutes. Additional studies coating implant surfaces with fibronec tin were also performed. The nature of the implant material itself app eared to affect the number of attached cells. Determined on a surface area basis, fibroblast attachment was greatest to titanium followed by non-porous hydroxyapatite. Porous hydroxyapatite demonstrated the lea st amount of fibroblast attachment. When incubated with fibronectin at a concentration of 50 mug/ml, no increase in the number of cells atta ched to the various implant materials was observed. A small but statis tically significant increase in the number of fibroblasts attached to porous hydroxyapatite at 40 minutes was observed when implant material s were pre-treated with fibronectin.