MMA，EGDMAを主成分とする直接法用常温重合型硬質リライン材の硬化挙動と機械的性質に及ぼす成分および粉液比の影響

摘要

We evaluated the influence of composition and powder/liquid (P/L) ratio on the setting characteristics and mechanical properties of autopolymerized hard direct denture reline resins composed of methyl methacrylate (MMA, monomethacrylate) and ethylene glycol dimethacrylate [EGDMA, dimethacrylate (cross-linking agent)], with poly (ethyl methacrylate) used as the powder, and a mixture of MMA and EGDMA containing p-tolyldiethanolamine as the monomer. Setting times were determined using an oscillating rheometer and mechanical properties were based on ISO specifications. Setting time increased exponentially with an increase in the ratio of EGDMA to MMA and decrease in P/L ratio. Materials with a liquid component of approximately 75-85 wt% EGDMA and a higher P/L ratio showed higher ultimate flexural strength and flexural modulus. Our results suggest that setting characteristics are more influenced by the ratio of monomethacrylate and cross-linking agent, whereas mechanical properties are more influenced by P/L ratio.