The effect of water storage and simulated cleansing on some properties of two newly developed denture base materials

Abstract

Heat-cured PMMA has been used to make denture bases about 80 years ago due to its having superior properties in comparison with other polymers. However, some properties need improvement, such as impact and fatigue strength and the long curing duration. Recently, new denture base materials have been developed and introduced to the market to overcome PMMA shortcomings. These new materials include the Eclipse resin system, a light-cured resin, and Weropress polymer, a pourable cold-cured resin, which can be polymerised in a relatively short time. No studies have been conducted measuring their properties for short and long term use. Therefore, these materials were tested and compared with heat- and cold-cured PMMA denture base materials, acting as positive and negative controls, respectively, to determine if they can be used as alternatives to conventional materials in long term use. The comparison was performed in terms of flexural properties, water sorption and solubility, surface properties (roughness and hardness), and colour stability. The comparison was made in three stages, at the baseline, after water storage for different time intervals, and after simulated cleaning with a liquid-based cleanser (Dentural), and a tablet-based cleanser (Poligrip). The findings showed that Eclipse was statistically superior to the positive control in all tested properties at baseline, after water storage, and after cleansing, except for roughness, although no statistically significant difference was found, while it was clinically superior in strength, hardness and colour stability. Weropress showed no statistically significant difference from that of the negative control, but did have very high colour stability, and it was not clinically lower than positive control except in strength. To conclude, in terms of the tested properties, Eclipse can be used as an alternative denture base material, while Weropress is recommended as a denture base material for cases with high aesthetic demands and low mechanical needs, or as a denture base material on a temporary basis.