Improving some selected properties of dental polyacid-modified composite resins

Polyacid-modified composite resins (compomers) are restorative dental materials that exhibit certain features of traditional dental composites and glass-ionomer cements. The aim of this paper was to develop experimental compomers with enhanced properties, based on adhesive monomers vinyl phosphonic acid and pyromellitic dianhydride glycerol dimethacrylate, and to compare their properties to those of commercially available products.

Factorial experimental design was employed to optimize both chemical and physical properties. Properties such as biaxial flexural strength (BFS), wear resistance (WR), water uptake (WU), and adhesion using shear bond strength (SBS) as well as fluoride release (FR) were evaluated and compared with those of commercial products.

Results were subjected to one-way ANOVA (p<0.05); significant differences were observed in properties of materials such as WR, BFS and SBS but not in WU and FR compared to commercial products. Experimental materials exhibited significantly higher WR, BFS and SBS values than commercial materials. Properties of materials were affected by their respective storage media with time.

Based on the results of this study, higher amounts of vinyl phosphonic acid (VPA), pyromellitic dianhydride glycerol dimethacrylate (PMGDM) and reactive glasses render the material with enhanced fluoride release and adhesion with properties similar to glass-ionomers whereas their decrease gives properties similar to conventional dental composite resins with improved properties such as strength and wear resistance.