The impact of sorption, buffering, and proteins on leaching of organic and inorganic substances from dental resin core material

Abstract

Dental core materials are resin-based polymers that act as support for overlying dental restorations. Interaction with aqueous media, such as saliva in the oral cavity or serum in the pulp chamber, can cause leaching of substances from core materials. These substances can potentially have serious effects to tissues. The purpose of this study was to delineate the factors that cause leaching and to quantitate both organic and inorganic substances that leach from core materials. Two core materials and one control material were stored in distilled water, artificial saliva, buffered artificial saliva, or artificial serum for 30 days at 37 degrees C. The materials were examined for changes in appearance and chemical composition, with a surface precipitate appearing on specimens stored in artificial saliva. The pH of the media was monitored and increased for all conditions. Organic eluants, triethyleneglycol dimethacrylate (TEGDMA), and camporquinone (CQ) were identified and measured in all media with high pressure liquid chromatography. Silicon, calcium, phosphate, and potassium were measured in the media using inductively coupled plasma optical emission spectroscopy. These results show that sorption, buffering, and the presence of proteins have an impact on the quantity of eluants that are leached from dental core materials.