Periodontal dressing materials have been used for patients’ comfort, wound protection and fixation of teeth for 70 years. Recent1y light-cured type periodontal dressing material, main component of which is polyether polyol, was introduced and is easy to control the setting time and esthetic with translucent pink shade. But there are potential of toxicity and decreasing of physical properties resulting from incomplete light curing. There have been many studies on toxicity but a few on physical properties. Material used in this study was ??(Caulk, U.S.A.) and specimen of 1 ×1 ×10mm was light cured at both ends and center to be stored at 37℃, 100% relative humidity for 30min. The curing time was 10, 20, and 30sec. The physical properties such as tensile strength, elongation and elastic modulus were measured using universal testing machine(Instron 6022, U.K.) at the cross-head speed of 10mm/min. The data were analysed using ANOVA.
Results were as followers:
1. The tensile strength of 10 sec. group was significantly, lower than others(p<0.05).
2. There was no significant difference in elongation among all groups(p>0.05).
3. For elastic modulus at 1% elongation, 10 sec. group was significantly lower than others(p<0.05).
4. For elastic modulus at 5% elongation, each group was significantly different from others(p<0.05).
5. The elastic moduli at 5% elongation of 10 sec. group and 30 sec. group were significantly higher than those at 1% respectively.
It was concluded that 20 sec. light cure would be effective in clinical use considering that the tensile strength and elastic modulus of this group were higher than those of 10 sec.
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