Mouthwashes increase surface roughness, color changes and decrease surface hardness of resin composites

A study was conducted to investigate the effect of various mouthwashes for COVID-19 prevention on surface hardness, roughness and color changes of bulk-fill and conventional resin composites and determine the pH and titratable acidity of mouthwashes.

Four hundred and eighty specimens were fabricated in cylindrical molds (10 mm in diameter and 2 mm in thickness). Before immersion, baseline data of surface hardness, roughness, and color values were recorded. Each product of specimens (Filtek Z350XT, Premise, Filtek One Bulk Fill Restorative, SonicFil 2) were divided into 4 groups for 0.2% povidone iodine, 1% hydrogen peroxide, 0.12% chlorhexidine, and deionized water (serving as a control). The specimens were immersed in mouthwashes for 1 minute and then stored in artificial saliva until 24 hours. This process was repeated for 14 days. After immersion, surface hardness, roughness and color values of specimens were measured at 7 and 14 days. The data were statistically analyzed by two-way repeated ANOVA, Tukey's HSD and a t-test (p<0.05).

Results

After immersion, all mouthwashes caused significantly lower surface hardness, greater roughness and color values (p<0.05) on all resin composites tested.

Mouthwashes had an effect on all resin composites evaluated by a significant decrease of surface hardness, and an increase of roughness and color values (p<0.05). Immersion in mouthwashes for COVID-19 prevention increased surface roughness and color changes and decreased surface hardness of the resin composites evaluated. Within the resin composite materials tested in this study, the greatest degradation was found in Premise after immersion in 0.2% povidone iodine.

Reference:

Saijai Tanthanuch, Boonlert Kukiattrakoon, Chailuck Naiyanart, Tanyanat Promtong, Panuwit Yothinwatthanabamrung, Suttida Pumpua, Effect of Mouthwashes for COVID-19 Prevention on Surface Changes of Resin Composites, International Dental Journal, 2022, ISSN 0020-6539, https://doi.org/10.1016/j.identj.2022.10.004