Mechanical effects of different Swiss market-leading dentifrices on dentin. Evaluation of cleaning potential, relative dentin abrasion and surface roughening

Abstract

In order to estimate the potential of dentifrices to harm exposed dentin, the mechanical properties of 15 dentifrices available in the Swiss market were investigated. A total of 120 bovine dentin samples were irradiated and analyzed for relative dentin abrasion (RDA). To investigate subsequent increases in surface roughness (Ra), dentin specimens (n = 180) were analyzed profilometrically at baseline and after brushing with test slurries. The cleaning efficacy (Ce) was determined using artificially stained tooth specimens (n = 180). The available fluoride content of the dentifrices was measured in respective slurries using an ion-selective electrode. The results of the mechanical analyses were categorized into four or five groups for each parameter. Four potential user groups were defined according to individual problem specifications and user demands. The results were compared to those of an earlier investigation of dentifrices published in 1998. The RDA results exceeded the values declared by the manufacturers and correlated significantly with the results of the Ra measurements. A significant positive correlation of RDA and Ce values was also shown. The measured fluoride content was often below the fluoride, declared by the manufactures. Only a few of the tested dentifrices qualified as suitable for all potential user groups. Major differences were observed between the mechanical properties found in the present study compared to those found in 1998. These changes in the properties of dentifrices during the past decade should be considered with respect to providing adequate recommendations for individual user demands.