Purpose: This study investigated the effect of adding diamond powder fillers from 5% to 20% by weight on thermal diffusivity of conventional heat polymerized acrylic resin. Materials and method: 63 samples of heat- polymerized acrylic resin were fabricated in present study. The samples were divided into three groups (n=7) coded TC, TS (TS5, TS10, TS15, TS20), TL (TL5, TL10, TL15, TL20). Group TC was the control group (i.e., non-reinforced conventional heat- polymerized acrylic resin samples). The samples of the groups TS and TL were reinforced with diamond powder fillers to achieve loadings of 5%, 10%, 15%, and 20% by weight. Cylindrical resin samples containing an embedded thermocouple were used to determine thermal diffusivity over a physiologic temperature range (00C- 700C). Results: The mean thermal diffusivity values of the heat- polymerized acrylic resin (in cm2 /sec) were 7.61, 8.94, 8.94, 9.11, 8.99, 8.70, 9.03, 8.77 and 10.34 for groups TC, TS5, TS10, TS15, TS20, TL5, TL10, TL15 and TL20 respectively. Thermal diffusivities of the reinforced acrylic groups were found to be significantly higher than the unmodified acrylic resin group. Thermal diffusivity of TL group was significantly higher than TS group. Conclusion: The thermal diffusivity of conventional heat- polymerized acrylic resin was increased by the addition of diamond powder fillers. Improving the heat transfer characteristics of the conventional heatpolymerized acrylic resin could lead to more patient satisfaction when used as a denture base material.

Thermal diffusivity; diamond powder fillers; PMMA; taste perception.