The Effect of Three Coating Materials on the Candidal Growth, on the Surface and Color of A heat–Cure Acrylic Resin Denture Base

Abstract

Aims:To evaluate the effect of three coating materials: Acrylic resin coating "monopoly", olive oil and grape seeds oil on the Candida albicans growth, and on color of a heat -cured acrylic resin denture base. Materials and methods: Three coating materials underwent pores method to find out their antifungal effect. The effect of coating materials on the acrylic denture base surface was determined via Sensitivity test in which twenty discs of acrylic resin 6mm diameter and 2mm thickness were prepared and divided into four groups: control (uncoated), monopoly, olive, and grape oil coated groups. These discs were added to Sabouraud Dextrose agar surface and incubated for 24 hours at 37 o C and the diameter of growth inhibition zones were measured. Then the Turbidity test was taken place, in which 60 acrylic specimens (1cm x 1cm x 2mm) were prepared and immersed in 60 test tubes that were divided into four groups, each group (15 specimens) was subdivided into three groups of incubation: 7, 20, and 30 days incubation period, each test tube contained 4 ml Brain Heart Infusion Broth, 0.1 ml of 24 hours Candida albicans, and its corresponding acrylic specimen, turbidity (yeast growth) was measured by a spectrophotometer at 530 nm wave length. For color change measurement test, 20 acrylic resin specimens (45 x 10 x 2.5 mm) were prepared and distributed into four studied groups. The absorbed light was measured by spectrophotometer and termed optical density at 345 nm. Results: All coating materials were fungicidal in pores method. Statistical analysis of sensitivity test showed that Candida albicans was susceptible at highest extent to monopoly coated denture base followed by the oils coated groups. In turbidity test, monopoly specimens showed antifungal activity in all periods of incubation, but the effect decreased gradually, olive and grape oil coated specimens exhibited their highest antifungal activity after 30 days incubation. Color change measurements showed that monopoly coated group had the highest optical density, while the olive and grape groups showed a decrease in the optical density when compared to uncoated group. Conclusions: Use of coating materials on the acrylic denture base surface was beneficial, especially monopoly in terms of antifungal activity against Candida albicans followed by natural oils (olive and grape oils). However, coating materials showed a significant change in the color of acrylic denture base.