Abrasive wear of packable posterior composites

ABSTRACT

This study was conducted to measure the abrasive wear of packable posterior composites, and to compare the wear resistance of the materials with that of universal composites and dental amalgam. Surface hardness was also measured to determine the relationship between hardness and volume loss due to wear. Two packable composites and two universal composites were used. Samples of a high-capper amalgam were used as reference material. Specimens of each material were prepared and subjected to toothbrush-dentifrice abrasion using 100,000 strokes of brushing. The amount of volume change of each material was calculated, and the Vickers hardness of test materials was also measured. Data were analyzed by one-way ANOVA, followed by the Duncan multiple range test and the Pearson correlation co-efficient at a level of P<0.05. Results indicated that packable composites exhibited significantly higher abrasion resistance than universal composites. Dental amalgam showed the lowest wear among the all tested materials. Significant relationship was observed between pooled data of volume loss and hardness. For individual material, however, non-significant association was noted. The improved wear resistance, and increased hardness of packable composites compared to universal composites may have been due to their improved chemical formulations