Abstract
To explore the feasibility of a new relining material, polymerization characteristics such as peak temperature, setting time, residual monomer, and postpolymerization were examined in ethyl methacrylate (EMA) resins composed of EMA and 4 kinds of EMA/methyl methacrylate (MMA) copolymers with high and low molecular weights and initiated by benzoyl peroxide/N, N-dimethyl-p-toluidine system and compared with those of MMA/PMMA resins. Peak temperature (53.8-71.0°C) and residual monomer (2.56-3.52% after 1h and 1.57-2.31% after 24h) of the EMA resins were significantly lower than those of the MMA resins (88.9-93.4°C and 4.61-5.85% after 1h and 4.09-4.84% after 24h, respectively). The composition of the copolymers had a significant effect on peak temperature and setting time but no significant effect on residual monomer and postpolymerization. The molecular weight of the copolymers affected peak temperature, setting time and residual monomer significantly. This study suggested that EMA resins are worthy of further evaluation as a relining material.
