Soft tissue attachment to titanium implants coated with growth factors.

Background: Enhancing the connective tissue seal around dental implants may be an important factor in implant survival. Purpose: The objective of the study was to investigate the effect of implant surface modification with either platelet-derived growth factor (PDGF) or enamel matrix derivative (EMD) on connective tissue attachment to titanium implants. Materials and Methods: Eighteen implants (Branemark (R) Mk III Groovy NP (3.3 mm Phi x 10 mm, Nobel Biocare) were implanted subcutaneously into 12 rats. Six implants each were coated with either PDGF or EMD immediately prior to implantation and six implants were left uncoated. Implants were retrieved at 4 and 8 weeks and assessed histologically to compare the soft tissue adaptation to the implant surfaces. Results: Ingrowth by soft connective tissue into the threads of all implants was noted at 4 and 8 weeks. Coating with growth factors did not alter the orientation of fibroblasts and collagen fibers. The depth of connective tissue penetration into the implant grooves was significantly greater for the implants coated with PDGF at 4 weeks. The thickness of the connective tissue in growth was significantly less for the implants coated with PDGF at 8 weeks. Conclusion: Coating of the implant surface with rhPDGF-BB or EMD can increase the speed and quantity of soft tissue healing around the implant surface.