纯钛种植体的2种表面处理对细菌黏附能力的影响

Influence of two different titanium implant surface modification methods on bacterial adherence

目的:研究2种表面处理(等离子渗氮和物理气相沉积TiN涂层)对钛表面的组织结构、性能及对变形链球菌黏附的影响。方法:将相同规格的钛片经逐级抛光后分别随机分成3组,每组3片,依次为抛光组,渗氮表面处理组,TiN涂层表面处理组。以抛光钛作为对照。测量所有试件表面的粗糙度值,并采用扫描电镜、金相显微镜(Axiovert 25CA)及辉光放电光谱仪(GDA750)对钛表面渗镀层的表面形貌进行分析;将材料接种变形链球菌悬液1h,在荧光显微镜下计数黏附细菌的数量。结果:2种表面处理仅使原有表面粗糙度略微增加,均在0.2μm以下;扫描电镜显示2种表面处理后材料表面的原始划痕消失;GDS检测分析结果表明:2种表面处理后,表面主要由氮化钛化合物组成。经2种处理后,钛表面黏附细菌的量显著地减少,而2种表面处理间细菌黏附量无显著性差异。结论:纯钛经2种表面处理后形成了稳定的改性层,且能减少细菌的黏附。等离子渗氮技术有望作为种植体穿龈部和种植体基台部的表面处理技术。

Objective：To investigate the effect of two different titanium surface treatment methods on Streptococcus mutans adhesion. Methods： Standard-sized and polished pure titanium were randomly divided into three groups,three samples each. One group was modified using plasma nitriding technique, another was treated employing physical vapour deposition （PVD coating） with titanium nitride （TIN） technique, the others were used as control. The surface was observed with a scanning election microscope. Estimation of surface roughness was done by a profilometer. The metallograph was viewed with metallurgical microscope （Axiovert 25CA）. In addition, elements distribution variation along cross-section of surface modified layer was studied with GDA750. Implants were incubated in the respective bacterial cell suspension for one hour. After washing, photographed and counted the adhered bacteria which was stained with acridine orange by fluorescence microscopy. Results： The surface roughness （Ra） of all surfaces examined was below 0.20μm, and two surface treatments only made the surface roughened slightly. Scanning electron microscopy proved some unevenly distributed microgrooves caused by polishing was disappeared in each modified surface, showing that two surface treatments changed or covered the original texture of the surface. The result of GDS showed that the surface modified layers were composed of titanium nitride. For pure titanium, a significant reduction of the number of adherent bacteria was observed on modified titanium surfaces, whereas no statistical signifieance was found between two surface treatments. Conclusion： The two surface modifications of titanium formed stabilized surface modifications and reduced the bacterial adherence. Plasma nitriding may be more suitable for use as surface treatment technique for the transgingival and abutment part of an implant.