Abrasiveness evaluation of silica and calcium carbonate used in the production of dentifrices.

Our purpose was to apply a radiometric method to an abrasiveness evaluation in samples of silica and calcium carbonate used as an abrasive in a dentifrice, to help in a prudent selection of materials by dentifrice producers. The results of RDA (radioactive dentin abrasion) abrasiveness indices obtained for these compounds varied from 136 to 19. The relative standard deviations of these RDA results varied from 5.9% to 11.8%, showing a good precision in the method. Also, the results obtained indicated that the abrasiveness indices increase with the particle size of the material. A comparison between different abrasives with similar particle sizes showed that silica presents higher RDA values than calcium carbonate.