Study On The Surface Properties And Bacterial Adhesion Of 2 Kinds Of Metal Materials After Polishing

Objective To study the effect of different polishing methods on the cobalt chromium alloy(Co-Cr)and pure titanium(Ti),to discuss the surface properties and adhesion of streptococcus mutans about two kinds of dental materials and provide a theoretical basis for clinical materials to choice different polishing method.Methods The cobalt chromium alloy and pure titanium made of 10mm×10mm×1.2mmsize specimen,30 pieces each,The two kinds of metal castings and cutting were randomly divided into A,B,C,D,E five groups,grinding the metal and then polishing with different methods,by scanning electron microscope(SEM)observed the surface microstructures,roughness of metal samples were measured,after sterilization of dental materials cultured streptococcus mutans in vitro,to conduct bacterial adhesion and statistical analysis.Results As the degree of polishing methods increased,the surface roughness and bacteria adhesion of the same metals showed a significant difference(P<0.05),the surface roughness and bacterial adhesion to the same amount of polishing method of different material groups were significantly difference(P<0.05),the roughness values measured by Co-Cr group were lower than those of pure titanium;under the scanning electron microscope,the surface of the two kinds of metal can be seen with casting porosity,and the scratch was decreased,the surface became more and more smooth,but using the polishing paste to the surface of the metal specimen can be seen bright spot.Streptococcus mutans in vitro was cultured 24 h specimen surface bacterial adhesion amount:cobalt-chromium alloy A,B,C group was less than that of pure titanium A,B,C group,But in the D group,the E group was higher than that of pure titanium group D,E group,the difference was statistically significant(P < 0.05).Conclusions As the degree of polishing methods increased,the surface roughness of the same metals decreased apparently,bacterial adhesion decreased gradually.experiment show the prosthesis should be carefully polished after grinding.comparison of cobalt chromium alloy and pure titanium specimen,after using polishing paste and polishing liquid,metal surface like mirror,which can achieve the ideal polishing effect.