A novel acrylic copolymer for a poly(alkenoate) glass-ionomer cement.

The interest in the clinical use of polyalkenoate cements stems mainly from their behavior as bioactive adhesive materials with therapeutic action. Glass-ionomer cements set by an acid-base reaction between a degradable glass and a poly(alkenoic acid) and the therapeutic action is related to the release of fluoride ions which are present in the hardened cement that show a sustained release over years, responsible for caries inhibition in teeth. Conventional glass-ionomers, however, suffer from some disadvantages such as short working time, initial moisture sensitivity and prone to desiccation after setting and are generally brittle. In the present study, a poly(alkenoic acid) copolymer was synthesized based on acrylic acid and 2-hydroxyethylmethacrylate (HEMA) using azobisisobutyronitrile as the initiator and characterized. The acid-base reaction was carried out by reacting aqueous solutions of the new copolymer (40 and 60%) with a commercial aluminofluorosilicate glasses as used in conventional glass-ionomer cements. The results showed that the copolymer of HEMA and acrylic acid was a viable poly(alkenoic) acid for formation of glass-ionomer cements.