Effect of chemical degradation followed by toothbrushing on the surface roughness of restorative composites

Abstract

ObjectivesThe aim of the present study was to assess the effect of the exposure to food-simulating liquids prior to brushing simulation on the surface roughness of five composite materials (Quixfil, Filtek Supreme, Esthet-X, Filtek Z250, Tetric Ceram). Material and methodsTwenty cylinders (5 mm diameter and 4 mm height) of each composite were randomly allocated to 4 groups (n=5), according to the food-simulating liquid in which they were immersed for 7 days at 37ºC: artificial saliva, heptane, citric acid, and ethanol. After this period, the top surface of composite cylinders was submitted to 7,500 brushing cycles (200 g load). Measurements of the surface roughness (Ra, µm) were carried out before and after the exposure to the chemicals/brushing simulation. Changes on the morphology of composite surfaces were observed through scanning electron microscopy (SEM). ResultsThe statistical analysis (ANOVA with cofactor / Tukey's test, α=5%) detected a significant interaction between solutions and composite resins. Esthet-X, Filtek Z250 and Tetric Ceram were not affected by the food-simulating liquids/toothbrushing. Citric acid and ethanol increased the surface roughness of Quixfil and Filtek Supreme, respectively. SEM images corroborate the surface roughness findings, demonstrating the negative effect from chemical solutions and mechanical abrasion. ConclusionsThe surface roughness of composite resin materials are differently affected by the food-simulating solutions, depending on the immersion media.

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

“…Degradation of composite materials can occur due to mechanical and chemical factors from the oral environment, which can cause changes in surface roughness, 11 loss of surface gloss, and increased discoloration of the material, 12 affecting the esthetic quality of the restoration. These changes have been attributed to the degradation of the polymer matrix, or the resin-filler interface, and loss of inorganic filler particles.…”

“…These changes have been attributed to the degradation of the polymer matrix, or the resin-filler interface, and loss of inorganic filler particles. 11,13,14 In non-stressbearing areas, the main causal factors of texture changes are the relationship between biodegradation and oral hygiene procedures. 15 Thus, regular prophylactic procedures, such as toothbrushing, the use of mouthrinses, or a combination of these, may produce deleterious side- effects on the surface and physical properties of restorative materials.…”

“…11,12 In our study, the specimens were immersed in artificial saliva during the experimental period. The leaching pattern has been shown to be consistent for at least one year, and was more evident for composites stored in artificial saliva than for those stored in distilled water.…”

Influence of Mechanical and Chemical Degradation in the Surface Roughness, Gloss, and Color of Microhybrid Composites

“…7 Satisfactory clinical performance of the material is required to ensure more resistance to chemical and mechanical degradation by the oral environment. 7 Thus, in vitro studies have analyzed the performance of composite resins with the influence of chemical and toothbrushing degradation separately.…”

Water sorption, solubility and surface roughness of resin surface sealants

“…It may also influence the speed of water diffusion into the material bulk and its potential degradation. Besides, a smooth surface tends to withstand better the wear imposed by tooth brushing and occlusal contact with antagonist teeth or food during mastication 2 .…”