Removal Effectiveness of Biofilms and Changes in Surface Roughness by Cleaning Methods of Denture Base Resin

Abstract

Purpose: To determine the criteria for the most efficient means of denture cleaning, we evaluated by means of in vitro assay the effects of current chemical and mechanical methods.
Methods: (1) Biofilms of Candida formed on denture-base resin pieces were immersed in denture cleansers or distilled water. Immersing or rinsing in water was repeated once a day for 5 days, and the test was repeated with denture cleanser. What remained was calibrated according to fluorescence levels in the medium supplemented with REDOX Indicator. (2) The effect was determined according to the roughness of the resin surface and the removal effectiveness of biofilms for the following experimental conditions: immersing in five kinds of denture cleansers, brushing with toothpaste, and brushing with denture paste.
Results: (1) The sterilization effect completely disappeared when the resin pieces were washed with only distilled water, even if denture cleanser had been used the previous day. A significant difference appeared in the amount of remaining Candida between the denture cleanser group and the control group (p < 0.05). (2) The surface roughness was increased further after brushing and increased even more after brushing with toothpaste because of the abrasives. In the removal effect of Candida biofilms, highly abrasive toothpaste produced significantly higher results than low abrasives, recognized not only with brushing, but the highest results were from denture cleanser.
Conclusions: Removal of denture plaque after cleaning with a brush having no toothpaste, the dentures should be immersed in a denture cleanser overnight every day.