关键词: 氧化锆, 变异链球菌, 粘附力, 表面粗糙度, 生物膜

Abstract: Objective To analyze the influence of the zirconia ceramic surface roughness on microbial attachment. Methods The surface of zirconia ceramics was abraded progressively into three roughness levels of rough, medium rough and smooth surface by silicon carbide sand papers. Then the surface roughness, surface morphology and contact angle of zirconia ceramic were measured by atomic force microscopy and optical contact angle measuring device, which was followed by detecting the adhesive force of different roughness of zirconia ceramic by Streptococcus mutans UA159 preprocessed probe. At last scanning electron microscope and confocal laser scanning microscopy were used to observe biofilm formation after co-culture of zirconia ceramics and Streptococcus mutans. Results For different roughness of zirconia ceramic surface, with the smoother degree of their surfaces, the contact angle decreases step by step, surface energy increases gradually, surface biofilm thickness decreases generally, and adhesive force between Streptococcus mutans and surface of zirconia ceramics decreases by degrees, whereas the biofilm bacteria mass of different roughness of zirconia ceramics does not have statistical difference. Conclusion Zirconia surface roughness affects the adhesion force of Streptococcus mutans which grows with the increase of surface roughness. The biofilm thickness and the mass of microorganisms lessened correspondingly with the decreasing of surface roughness, until it drops to a certain number, from where the biofilm thickness and the mass of microorganisms remains stable.

Key words: Zirconium oxide, Streptococcus mutans, Adhesive force, Surface roughness, Biofilm