The Effect Of Different Titanium Surface Topographies On The Biologic Behavior Of Human Gingival Fibroblasts

Objective:Histiocytes and oral pathogenic bacterium compete to attach to the implant surface. If histiocytes attach to the implant surface firstly, the surface, which is cell fusion with histiocytes, can resist the adhesion of bacterium for the activity of the histiocytes ,the integrity of cell membrane, polysaccharide and the functional defense mechanism of the host; If pathogenic bacterium attach to the implant surface firstly, which can lead to the infection of periimplant, and influent the healing of histiocytes on the implant surface. Once the bacteria adhesion takes place, histiocytes hardly replace the bacteria sites to integrate with the implant surface. So, it is the most important thing for improving the integrity between the implant and soft tissue interface to establish the adhesion of histiocytes on the implant surface as early as possible. The purpose of this study is to evaluate the effect of three different titanium surface characteristics on the biological behavior of oral fibroblasts, and to find a proper surface characteristic for the adhesion of the gingival collagen fibers, which can provide guidance for the designation of the implant cervical part.Methods:Titanium surface created by machining, electrolytic etching, and electrolytic etching and acid etching were analyzed using laser scanning confocal microscope (CFM) and field emission scanning electron microscopy (FSEM). Human oral fibroblasts were cultured on different surfaces. The proliferation of cells was examined using MTT reduction assay. Cell spread and morphology of cell and extracellular matrix were evaluated using FSEM.Results:the machined surface showed a comparatively smooth profile with shallow isotropic grooves. Its roughness of micro structure was 1.145±0.6207μm; The ECE surface showed a little roughened surface with well-distributed round or ellipse shallow patellate macropores whose diameter was 10~15μm, and with the deeper micropores whose diameter was 1.5~4.5μm contained in the macropores. The ECE surface did not show up nanometer grannulo-crystals. Its roughness of micro structure was 2.753±0.3711μm; The ECA surface showed a little roughened surface with well-distributed round or ellipse shallow patellate macropores whose diameter was 10~15μm, and with the deeper micropores whose diameter was 1.5~4.5μm contained in the macropores. The ECE surface showed up nanometer grannulo-crystals whose diameter was about 50~100nm. Its roughness of micro structure was 2.648±0.5011μm; Oral fibroblasts on the three different surfaces grew well and had a normal morphology. The growth curve of oral fibroblasts on the three different surfaces was similar with the growth curve of normal cells. It showed that all the three titanium specimens did not have obvious cytotoxicity. The cells on the machined surface were thin and flat, similar to round, with a parallel orientation. The cells did not spread very well and had brevis processus pseudopodia; the cells on the ECE surface were polygon, and Randomly distributed. The cells spread well and had longer processus pseudopodia than the machined surface with some pseudopodia putting in the pore; the cells on the ECA surface were polygon, and Randomly distributed. The cells spread very well and had the longest processus pseudopodia with some pseudopodia putting in the distant pore and could form three-dimension structure suspended in midair. It demonstrated that cell attachment was significantly weaker on the machined surface than on the ECE and ECA surfaces, and cell attachment was strongest on the ECA surface.Conclusion:The ECA surface had the strongest effect on the attachment of human gingival fibroblast. The machined surface had the weakest effect on on the attachment of human gingival fibroblast.