The Effect Of Different Polishing Methods On The Surface Roughness And Bacteria Adhesion Of Three Dental Metals Rough Surface

ObjectiveTo compare the effect of different polishing methods on the three dental prosthetic metals rough surface,for doctors choose appropriate polishing method and reduce the occurrence of denture stomatitis provide reference.MethodsThe casting of Vitallium2000alloy, cobalt-chromium alloy and titanium were respectively processed into the size of10mm*10mm*1.0mm in tablets. Each material was prepared for24specimens, The three kinds of metal castings were divided into four groups after conventional polishing according to different polishing methods. Roughness of metal samples were measured and the data were analyzed.The surface microstructures were observed by scanning electron microscope(SEM).Then the adhesive bacterial amount was measured by the clone forming unit counting methods.Result1) As the degree of polishing methods increased,the surface roughness of the same metals decreased apparently(P<0.05).except method C and method D in Co-Cr group and Vitallium2000group. Microscopic observation of the surface morphology is corresponding to the result.2) The surface roughness of Co-Cr group and Vitallium2000group was lower than titanium group with same polishing methods.and the difference was statistically significant (P<0.05),Co-Cr group and Vitallium2000roughness values showed no significant differences.3) Bacterial adhesion experiment’s results showed that the same metal material with the increase of polishing process, the amount of bacterial adhesion was obviously decreased with significant difference (P<0.05),except method C and method D in Co-Cr group and Vitallium2000group, the difference was statistically significant (P>0.05).For Co-Cr alloy,Vitallium2000alloy and pure titanium in the same polishing method, the amount of bacteria adhesion between two groups had no significant difference (P>0.05)Conclusion1) With the increase of the polishing process,the surface roughness of pure titanium was decreased.The surface roughness of Co-Cr group and Vitallium2000group also decreased with the increase of the polishing process,except method C and method D.It shows that method D is effective to pure titanium group,but for Co-Cr group and Vitallium2000group is no significant.2) There is no difference between cobalt-chromium alloy and Vitallium2000with same polishing method,but for pure titanium is poorer than other materials.3) With the decrease of the surface roughness,the amount of the bacterial adhesion on the surface was decreased in the same material. Polishing can effectively decrease surface roughness,inhibit bacterial adhesion.4) The surface roughness of pure titanium is higher than other materials with same polishing method,but the amount of bacteria adhesion was no significant difference.It likely that the bacteria adhesion of pure titanium is not only related to the surface roughness,but also associated with the characteristics of pure titanium itself.