Evaluating the intensity of microwave emission power in processing heat cured silicone soft liner

A comparative laboratory study was done to evaluate the effect of different curing techniques using the conventional water bath heating method and microwave energy on the tensile strength and tensile bond strength of heat cured soft liner. The results obtained from this study indicated that the use of microwave intensity to 100% [2450 MHZ] while the time is constant [14 minutes] increased the mean values of both tensile strength and tensile bond strength of silicone soft liner and showed no significant difference when compared to the specimens cured using conventional method. Processing of heat cure silicone soft liner using microwave energy may replace conventional water bath heating method for saving time and reducing efforts

Comparison of resistance of two types of heat-curing resins to impact force

Accidental fracture of acrylic dental appliances is common during denture service. Recent efforts had been made to improve this deficiency by developing different polymers bases upon polymethyl methacrylate with the addition of rubber. In this study, specimens were prepared according to the British St and ard Specification No. 771 to evaluate the impact of strength of high impact type and conventional heat-cure polymethyl methacrylate in relation to two different curing techniques. The fracture surfaces of two specimens of each group were examined using scanning electron microscope in order to study their microstructure. The results obtained from this study demonstrated a significant increase in the impact strength of high impact type [group 2] than conventional heat-cure polymethyl methacrylate [group 1]. A high significant increase in impact strength was observed in group 4 of high impact type when cured for long time at constant temperature and this technique may reduce the accidental fracture of acrylic dental appliances