Purpose: It is not definite about how much knowledge, experience, and opinion the dental students have about denture cleansers. The purpose of this study was to investigate the interest and knowledge about denture cleansers of dental student in Japan, China, and Indonesia.
Materials and Methods: Forty-seven dental students from Japan (Hiroshima University), 38 dental students from China (Hebei Medical University and Wuhan University), and 29 dental students from Indonesia (Airlangga University) were surveyed in this study.
Results: The response rate was 92.1%. Significant differences were found among the three countries for all questions. For the question “Have you heard of denture cleanser?”, 100% of Japanese students answered “Yes”, whereas 40.5% of Chinese students and 13.8% of Indonesian students answered “No”. Japanese students recognized denture cleansers in TV commercials more often than Chinese and Indonesian students (Q8). For the question “Do you think the use of denture cleanser is more effective than a clinical intervention?”, about 75% of the subjects in Japan answered “Yes”; however, over 55% of subjects in China and Indonesia answered “No”.
Conclusion: The results suggest that there are differences in the awareness and knowledge about denture cleansers among the three countries of Japan, China and Indonesia. Chinese dental students had the least knowledge about denture cleansers compared with the other two countries.

Purpose: This study evaluated the adhesive strength between a thermoplastic poly(ethylene terephthalate) (PET) sheet and an auto-polymerized acrylic resin (Unifast III).
Materials and Methods: The shear bond strength of auto-polymerized acrylic resin to PET with or without surface treatment was measured. Four surface treatment agents, Unifast III Liquid, Resin Primer, Adhesive, and GP Solvent, were used.
Results: The shear bond strengths were 28.8 MPa for GP Solvent, 26.5 MPa for Resin Primer, 24.6 MPa for Adhesive, 24.4 MPa for the untreated control, and 23.4 for Unifast III Liquid. Significant differences were found between the control and GP Solvent, between Unifast III Liquid and GP Solvent, and between Adhesive and GP Solvent (p<0.05). SEM observation showed that the surfaces of the thermoplastic sheets had dissolved due to the application of Unifast III Liquid, Adhesive, and Resin Primer.
Conclusion: Specimens treated with GP Solvent, Resin Primer, and Adhesive exhibited higher bond strength value compared to the control specimens. GP Solvent had the highest adhesive strength. SEM observation indicated that the surface changes of the PET treated with Resin Primer were the most remarkable.