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Objective: To study the change in properties of heat-polymerized acrylic resin after using one denture cleanser., Methods: In the study, 20 disk-shaped (50.0 mm×0.5 mm) and 40 rectangular (34.0 mm×13.5 mm×1.3 mm) specimens prepared from heat-polymerized acrylic resin were randomly divided into four groups. The specimens were exposed to one of the three treatments as follows: Group 1 was without any treatment, Group 2 was exposed to air, Group 3 to distilled water, and Group 4 to Polident. The 4 exposures lasting 8 hours were conducted daily and repeated for 30 days. The color stability of heat-polymerized acrylic resin was determined by visual methods. The flexural strength and bonding strength of acrylic resin were measured using a universal testing machine. All the results were analyzed using ANOVA., Results: The flexural strength test of acrylic resin demonstrated significant differences between Group 4 and Group 1 (P<0.05), there were no significant differences among Group 1, Group 2 and Group 3. No significant differences were found in other properties of the test materials., Conclusion: Long-term use of polident could alter the physical and mechnical properties of heat-polymerized acrylic resin. It may be related to the accelerating aging of resins caused by certain chemicals in denture cleansers. Polident may have some adverse effects on denture materials for decreasing flexural strength of heat-polymerized acrylic resin after 30-day immersion.

Objective: Herein, the synthesis, component, microstructure and pharmacological and toxicology researches of the Synthetic Mercury Sulfide (S-HgS) a kind of common drug in Chinese, Mongolia, Tibetan medicine, and Indian medicine system were summarized. The similar cognition about mercury toxicity & pharmacological action from some Asian regions was analyzed, and it can supply some useful direction for the traditional Asian medicine system., Method: Recent literatures both domestic and abroad were summarized and analyzed., Result: S-HgS is the basis of Vermilion, Mongolia-Vermilion, Zuotai, and Ras-sindoor. Athough the processes of synthesis are very different, but the microstructure and pharmacological & toxicology of S-HgS is similar., Conclusion: S-HgS has a far-ranging application,and unique curative effect. New technology such as nanotechnology can be used for improving the advancement of traditional Asian medicine.