Abstract:

Abstract:Objective To compare the effects of five different titanium surface characteristics of implants on gingival soft tissue interface and to find a proper implant neck surface characteristic for the preferable adhesion of the gingival soft tissue.Methods The  titanium implants were  processed by electrochemical methods to form four different surfaces,namely the Nano morphology of acid etching group (AE group),the Micron morphology of electrochemical etching group 1 and 2 (ECE1 group and ECE2 group),the micro or Nano morphology of electrochemical etching and acid etching group(ECA group);and the smooth morphology in smooth group (S group) was used as control.These five kinds of implants were immediately implanted in the mandible of 6 experimental dogs in a certain order.The dogs were sacrificed respectively after 20 d and 3 months,and then the specimens were manufactured and scanning electron microscope was used to observe the bonding interface of the gingival with the implant surface.Results The gingival epithelium bonded with the implant surface closely.No significant difference was found among all groups;after removal of soft tissue,there was no epithelial tissue remaining on implant surfaces.The collagen fibers in S group adhered and paralleled with the implant surface,and most of the collagen fibers dehisced and separated from implant surface;and few residual collagen fibers remained on implant surface.The collagen fibers in other groups were vertical to the implant surfaces.The interface of gingival tissue and implant surface formed complex micro-Nano mosaic structures,and the gingival tissue dehisced less from implant surfaces compared with S group;the collagen fibers remaining on the implant surface  in ECE2 group and  ECA  group were more than those in AE group and ECE1 group.Conclusion The micron and micron - nanometer surface can significantly  improve the adhesion of the gingival soft tissue on the implant with the methods of electrochemistry.

Key words: soft-tissue interface, micron morphology, nano morphology, scanning electron microscopy