Effects of disinfection with a vinegar-hydrogen peroxide mixture on the surface characteristics of denture acrylic resins

Objective This study aimed to investigate changes in the surface characteristics of two denture resins when disinfected with a vinegar-hydrogen peroxide (VHP) mixture. Materials and Methods Microwave-polymerized or 3D printed acrylic resin disks were immersed for 900 min (simulating 90 daily uses) in the following solutions ( N = 10): water; 0.5% sodium hypochlorite; hydrogen peroxide and water dilution (1:1 ratio); vinegar and water dilution (1:1 ratio); and VHP mixture. Surface roughness, Knoop microhardness, surface free energy, and scanning electron microscopic images were assessed before and after the immersions. Results were compared using the 2-way ANOVA for repeated measures and Tukey test, at 5% significance. Results Surface roughness and microhardness did not differ ( P > .05) among the solutions and times. Surface free energy and its dispersive component increased ( P < .05) for all solutions. All solutions, except for water and VHP mixture, degraded microtopography. Conclusions The VHP mixture was not deleterious to conventional and 3D-printed resin surfaces. Clinical relevance Conventional and 3D printed resin dentures can be disinfected with a VHP mixture in a 1:1 ratio because this mixture does not substantially affect the surface characteristics after 90 daily immersions. On the contrary, sodium hypochlorite, hydrogen peroxide, and vinegar solutions, even in low concentrations, should be used with caution for denture disinfection because they may alter the resin microtopography over time.