Real-Time Attenuation Coefficient of Experimental Non-Filled Resin Composites

Abstract

Polymerization shrinkage of resin-based composites is the primary reason leading to the eventual failure of the set filling. The failure is usually preceded by several detrimental events, among which bacterial adhesion and colonization on the gap formed between the shrunk filling and adjacent cavity. The incorporation of bioactive glass (BG) to resin-composites (RBCs) is being extensively investigated as it offers “antimicrobial activity” through the release of ions (mainly Ca2+, PO43-) to neutralize acids produced by cariogenic bacteria, as well as encourage tooth remineralization. The extent of light attenuation fillers like BG causes will potentially impact the degree of conversion leading to impaired mechanical and biocompatible properties of RBCs. This will determine the suitability of the set resin to serve in the oral cavity. Using the physics of light and chemistry of RBCs, some authors predicted the degree of conversion and depth of cure of certain commercial RBCs through applying Beer-Lambert’s Law, and proved its applicability considering all matrix constituents. The present work aims at investigating the applicability of the law as a function of time on experimental non-filled resin composite, and consequently using a similar approach to calculate real-time attenuation coefficient of BG through optical density measurements. The hypothesis of the present paper is that Beer-Lambert’s Law is applicable to calculate real-time attenuation coefficient of experimental non-filled resin composites.