In vitro toothbrushing abrasion of dental resin composites: packable, microhybrid, nanohybrid and microfilled materials

Abstract

This study evaluated weight loss and surface roughening after toothbrushing of different resin composites: one packable (Solitaire 2, Heraeus Kulzer), one microhybrid (Charisma, Heraeus Kulzer), one nanohybrid (Simile, Pentron) and one microfilled (Durafill VS, Heraeus Kulzer). Cylindrical specimens (n = 20) were prepared. Half of the samples were submitted to 60,000 strokes, at 4 Hz, with a dentifrice-water slurry. Control samples (n = 10) remained stored at 37°C. Pre-and post-abrasion parameters for weight (mg) and surface roughness (Ra, µm) were determined on an analytical balance and a surface profilom-

The influence of mouthrinses and simulated toothbrushing on the surface roughness of a nanofilled composite resin

“…4 The degradation of resin composites is a complex mechanism that depends on the characteristics of the composite, such as the size, 17 volume and type of inorganic filler, 2,4,18 matrix composition, and degree of conversion. 19 The most likely explanation for degradation is the presence of nanosized particles (5-20 nm) throughout the resin matrix, 7 which results in less space between the particles, and ultimately more protection of the softer resin matrix 4,20 and less filler plucking, 20 compared with other types of resins. This leads to lower resin porosity 21 and improved abrasion resistance of the material.…”

“…This leads to lower resin porosity 21 and improved abrasion resistance of the material. 4,21 Conversely, the types and volumes of inorganic fillers also influence the degradation, which in turn results in higher or lower material solubility. Theoretically, a larger total surface area of nanofilled particles with nonagglomerated 20 nm silica fillers allows more water to accumulate at the filler particle-polymeric matrix interfaces, thus increasing salivary sorption and solubility.…”

“…It has been found that the major factors influencing abrasion are dentifrice and toothbrush characteristics. 4 Factors related to dentifrice are the type of abrasive, sizes of particles, and the dilution proportion, while factors related to the toothbrush are the number, stiffness, and shapes of tufts and bristles. 4 In addition, a soft toothbrush was used to promote low abrasion.…”

“…The surface roughness can increase due to the abrasion of the polymer matrix, subsequently followed by filler exposure, and finally loosening of filler particles. 4 In addition, mouthrinses can contain alcohol and other substances, such as detergents, emulsifiers, and organic acids, that can lead to the degradation of the composite resin surface. 5 According to Gürgan et al, 6 mouthrinses can afDeclaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.…”

“…Recently, nanofilled composites were introduced in an attempt to provide a restorative material that could be used in both anterior and posterior areas, associating high initial polishing with superior polish and gloss retention. 4,7 There is still much to be learned about this resin. Our study hypothesis was that the surface roughness increases with the use of mouthrinse solutions when associated with toothbrushing.…”