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Poly(alkenoic acid)s based on copolymers of acrylic acid and itaconic acid were synthesized and further modifiedwith glutamic acid (Glu) and glycidyl methacrylate (GMA). The resultant polymers were characterized by means of protonnuclear magnetic resonance, gel permeation chromatography, and elemental analysis. Specimens of resin modified glassionomer cement (RMGIC) prepared from the cement-forming reactions between the synthesized polymers and a commerciallyreactive glass were fabricated and investigated for flexural strength using three-point bending test. The effects of differentamounts of Glu and GMA on the flexural strength were evaluated. The results showed significantly improved cement strengthdue to the incorporation of Glu into the copolymer with an optimal feed of Glu and GMA at 0.1-0.2 and 0.4 per mole ofcopolymer, respectively. The addition of 2-hydroxyethyl methacrylate (HEMA) to the RMGIC formulations tremendouslyincreased the cement strength. In this study, a formulation containing 20%-wt. of HEMA and 45%-wt. of polymer concentration gave the highest flexural strength with 62.7±3.4 MPa.

Glass ionomer cements (GICs), widely used as restorative materials in dentistry, are principally composed of fluoroaluminosilicateglass powder combined with a water-soluble polyacid. The investigation of new glass compositions and polyacid components are very important to improve the mechanical properties of these cements. The objective of this work was to prepare glass ionomers and polyacids for the use as GICs. The effects of spherical bodies, Al2O3:SiO2 ratios, replacing CaO by SrO, and ZrO2 adding in glass powder in combination with the variation of acidic copolymer concentration on the compressive strength were investigated and discussed.