Abstract: Three methods for the in-vitro measurement of dentifrice abrasion performance,the radiotracer method (ISO11609/Annex-A),the surface profile method (ISO11609/Annex-B) and a recently introduced method (the surface roughness method) were examined,investigated and compared.The results showed that in case the dentifrices were composed of same type of abrasive agent,either silica or natural calcium carbonate,test results Ra value obtained from surface roughness method,RDA value obtained from radiotracer method as well as the result obtained from surface profile method all display good correlations.Meanwhile,as comparing with the two methods specified in ISO11609,the surface roughness method displays other advantages such as simple operation,pressure controllable in the brushing and abrasion process,high performance price ratio,good repeatability et al.Besides,the results of the surface roughness method are more stable and not affected by the interference of the phosphate in the dentifrice formulations.

Key words: dentifrice, abrasivity, surface roughness method, radiotracer method, surface profile method