Effect of various beverage immersions on the color stability and degree of cure of two types of dental resin composite materials: An in vitro study

Abstract

Among the wide range of polymer matrices, polymethyl methacrylate (PMMA)-based matrices can be considered the most common polymer in dental applications. Significant parameters, such as conversion degree and change of color of two commercial brands, nano-filled composite resin, NovaPro (N), and micro-hybrid composite resin, VladMiVa (V), were investigated after curing and immersing the dental specimens in different drinks for one and seven days at 37°C. Raman spectroscopy was used to evaluate the degree of conversion (DC) by measuring the ratio of the absorption bands related to aromatic and methacrylate C=C stretching modes. These ratios were of the same value. CIE (Color Imaging Experiment) was used to investigate the color change of the filling resins. The N composite has a noticeable color change in coffee after 24 hours and almost the exact change after one week. Yogurt also significantly affects the color stability of the same composite just after one week of immersion. Cola dramatically affects the color of the same composite after one week of immersion. For the (V) composite, the effect of the drinks after immersion for 24 hours and after one week was within the acceptable limit and non-noticeable by the naked human eye, which means it has better color stability than the (N).