Background information about normal periodontalanatomy and titanium used in endosseous implant fabrication is provided. Literature is reviewed concerning epithelial and connective tissue attachment to titanium. Information about the adequacy of cell attachment to implants, possible mechanisms of cell attachment formation, and the effect of implant surface properties on attachment is presented. A chemical attachment between titanium implant surface oxide layer and epithelium has been demonstrated in vitro and in vivo. This attachment is mediated by a glycoprotein similar to that seen between epithelium and natural tooth surfaces. While only minimal histological evidence exists, connective tissue fibers adjacent to titanium implanted surfaces may bring the tissue in tight apposition to the implant without an absolute biologic attachment between the implant and connective tissue. Alteration of the titanium surface morphology may selectively enhance the attachment of either epithelial cells or fibroblasts, theoretically enhancing the formation of a biologic seal between the implanted titanium surface and its adjacent tissue. A greater understanding of the mechanisms of attachment and of the factors which enhance the integrity of the biologic seal between implant and soft tissues should permit an improved prognosis for functioning titanium implants.J Periodontol 1991; 62:153—160.