Impact of Laser-modified Abutment Topography on Peri-implant Mucosal Integration

A dental implant is an artificial "root" for a missing tooth made out of surgical grade metals, usually titanium, which is placed in the jaw. An implant is designed to provide a strong foundation for an artificial replacement tooth, also called a "crown". An abutment is a medical grade connector, usually made of titanium, which is placed on top of the implant, and is designed to hold and connect the crown to the implant. A crown, also called a "dental cap" is an artificial tooth, generally made of porcelain or surgical grade metals. Osseointegration is defined as the fusion of a dental implant and abutment with the surrounding jaw bone and is a critical step during implant therapy. During this process, the titanium and bone need to become one solid structure (without any intervening inflammatory mucosal tissue in between) for optimum strength and viability. It is hypothesized that use of an abutment whose surface has been etched with a laser ("laser-etched") will enhance the attachment of the abutment to the surrounding bone and mucosal tissue and optimize healing. The goal of this research is to compare, by split mouth design, the healing process of peri-implant mucosal tissue adjacent to a standard healing abutment (not laser-etched) versus mucosal tissue healing adjacent to a laser-etched abutment . Each subject will receive two implants. One implant will receive (by randomization) a standard titanium healing abutment that is not laser-etched. The other implant will receive a laser-etched ("Laser-Lok") abutment. Subjects will be sequentially subdivided into 4 groups (n=5) and scheduled for a biopsy of peri-implant tissue at both implant sites at either 8 weeks, 4 weeks, 2 weeks or 1 week after implant surgery. The biopsies, about the size of a grain of rice, will be analyzed using histological and molecular techniques to identify cellular changes in response to laser-etching. Approximately 8 weeks after implant placement, subject will have abutments removed and digital impressions taken for final crown fabrication. At approximately 11-12 weeks post implant placement, final crowns will be placed. Subjects return to clinic at approximately 1 year post surgery for a final study visit to assess the peri-implant mucosa around both implants as measured by bleeding upon probing, probing depth and peri-apical radiography.