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

Abstract

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.

Bone and Gingival Connective Tissue Responses towards Nanosecond-Pulsed Laser-Treated Titanium Implants

“…Interestingly, those fiber groups had perpendicular rod-like attachments with the implant surfaces at intervals of 30 m (asterisks in Fig. 12b and c), similar to the characteristic morphology seen in the gingiva and periodontal ligaments of natural teeth 11) . Such rod-like attachments were not observed in the Laser-Ti and Coll/Laser-Ti implants at 3 weeks.…”

“…In our present study, collagen immobilization did not enhance attachment of gingival connective tissue compared with the LaserTi implants. Raita et al reported that three-dimensional collagen nanofiber structures were more effective for gingival connective tissue attachment than two-dimensional collagen immobilization 11) . Atsuta et al showed that laminin-5 contributed to attachment of the peri-implant epithelium to the titanium implant surface 32) .…”

“…Perpendicularly oriented birefringent collagen fibers were observed on the roughened surfaces of Laser-Ti and Coll/Laser-Ti implants. Raita et al reported that some birefringent collagen fiber bundles in the gingival connective tissue were perpendicularly oriented to the collagen nanofiber-coated implant surface 11) .…”

“…The implants were inserted into the extracted sockets of the maxilla of the rats as described previously 11,24) . Surgeries were conducted under general anesthesia by intraperitoneal injection of ketamine hydrochloride (47 mg/kg) and medetomidine hydrochloride (0.4 mg/kg).…”

“…Nylon-coated or titanium mesh-coated titanium has been reported to be effective for promoting anchoring to soft tissue following subcutaneous implantation in rats [9][10] . Raita et al deposited collagen nanofibers onto titanium implants with an electrospray deposition method and concluded that collagen nanofiber-coating may improve gingival connective tissue responses to titanium implants 11) . Among surface modification techniques, we focused on a laser processing procedure for controlling surface topography and chemistry.…”