IADR Abstract Archives
Effect of Curing/Storage Conditions on Biaxial-Flexural-Strength of Resin Cement
Objectives: This study examined the effect of specimen storage conditions on the biaxial-flexural-strength (BFS) of resin cement with or without light irradiation.
Methods: A commercially available dual-cured resin cement (Panavia V5, Kuraray Noritake Dental) was examined. Disc specimens were fabricated using vinyl chloride mold (15-mm diameter, 1-mm thickness) and light cured for 27s each at the top and bottom surface by a curing lamp [light-cured group, L(+)]. The specimens without light irradiation [self-cured group, L(-)] were prepared in the darkroom. All specimens were stored at 37±2°C and 95±5％ relative humidity in the container. One hour after the start of cement mixing, specimens were removed from the mold. The specimens were stored in either dry conditions with silica gel (Dry), deionized water at 37±2°C (Water), or Soxhlet extractor using deionized water at 90±5°C (Heated-water) up to 24 hours after start of cement mixing (n=10 each). The BFSs of specimens after storage were determined using the universal testing machine (3366, Instron) at a crosshead speed of 1.0mm/min at room temperature. The results were analyzed using Two-way ANOVA/Sheffé's test (α=0.05).
Results: Measured BFSs are shown in Fig. ANOVA indicated that there were significant effects of specimen storage conditions and light irradiation on BFS (p<0.05). For L(+), Dry specimens had the greatest BFS among all storage conditions (p<0.05). For L(-), there were no significant differences in BFS among the storage conditions (p>0.05). The BFSs of L(-) specimens were lower than those L(+) specimens in Dry (p<0.05). No significant differences in BFS were found between L(+) and L(-) specimens for Water and Heated-water groups (p>0.05).
Conclusions: Although the BFS of light-cured group reduced under the conditions with water, those of self-cured group were less affected by the storage conditions under the present experimental conditions.
Methods: A commercially available dual-cured resin cement (Panavia V5, Kuraray Noritake Dental) was examined. Disc specimens were fabricated using vinyl chloride mold (15-mm diameter, 1-mm thickness) and light cured for 27s each at the top and bottom surface by a curing lamp [light-cured group, L(+)]. The specimens without light irradiation [self-cured group, L(-)] were prepared in the darkroom. All specimens were stored at 37±2°C and 95±5％ relative humidity in the container. One hour after the start of cement mixing, specimens were removed from the mold. The specimens were stored in either dry conditions with silica gel (Dry), deionized water at 37±2°C (Water), or Soxhlet extractor using deionized water at 90±5°C (Heated-water) up to 24 hours after start of cement mixing (n=10 each). The BFSs of specimens after storage were determined using the universal testing machine (3366, Instron) at a crosshead speed of 1.0mm/min at room temperature. The results were analyzed using Two-way ANOVA/Sheffé's test (α=0.05).
Results: Measured BFSs are shown in Fig. ANOVA indicated that there were significant effects of specimen storage conditions and light irradiation on BFS (p<0.05). For L(+), Dry specimens had the greatest BFS among all storage conditions (p<0.05). For L(-), there were no significant differences in BFS among the storage conditions (p>0.05). The BFSs of L(-) specimens were lower than those L(+) specimens in Dry (p<0.05). No significant differences in BFS were found between L(+) and L(-) specimens for Water and Heated-water groups (p>0.05).
Conclusions: Although the BFS of light-cured group reduced under the conditions with water, those of self-cured group were less affected by the storage conditions under the present experimental conditions.
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