Influence of Tooth Paste Particle Size and Tooth Brush Stiffness on Dentine Abrasion in vitro

Abstract

The influence of particle size and tooth brush stiffness on abrasion of dentine was determined by means of a brushing machine, using 1,000, 2,000, 5,000, and 10,000 strokes and 200 g tooth brush load. Tooth pastes with two particle sizes were used: 7 and 15 μm diameter for the CaCO3 and 8 and 13 μm for Al(OH)3 abrasive systems. Abrasion was measured by a surface profilometer system and expressed in mean depth. The results show that (1) abrasion was always linearly correlated to the number of strokes; (2) nearly independent of the tooth paste system the abrasion is roughly 1.4 × more severe for the medium than for the soft brush; (3) the abrasion rates (average thickness removed per stroke) prooved to be significantly (p < 0.05) different for all four tooth paste systems, and (4) larger particles lead to higher abrasion rates for both abrasive systems.