Pilot study of gingival connective tissue responses to 3-dimensional collagen nanofiber-coated dental implants.

The aim of the present study was to evaluate the gingival connective tissue response to screw-type titanium implants coated with Type I collagen nanofibers, which were prepared using the electrospray deposition method. Implants were immediately inserted into the socket of maxillary first molars after the extraction. Undecalcified sections after 4 weeks implantation were histologically observed. Better contact of the gingival connective tissue was generally observed around the collagen nanofiber-coated implants than titanium and non-fibrous collagen-immobilized implants. Gingival connective tissue to implant contact was significantly greater with the collagen nanofiber-coated implants than with the titanium and collagen-immobilized implants at the distal side, but not at the mesial side. Polarized light microscopy revealed that some birefringent collagen fiber bundles are oriented perpendicularly to the implant surfaces in the gingival connective tissue adjacent to the collagen nanofiber-coated implants. Collagen nanofiber-coating may have a possibility for improving gingival connective tissue response to titanium implants.