Surface Hardness of Hybrid Ionomer with Different Curing Time (In Vitro Study)

Objective: The aim of this study was to evaluate the surface hardness of hybrid ionomer with different curing times (20, 30, 40, and 50 seconds). Methods : This was an experimental laboratory with posttest only group design. Twenty-four disk shape hybrid ionomer specimens with a diameter of 5 mm and 2 mm in thickness were prepared and polymerized with Quartz Tungsten Halogen (QTH) for 20, 30, 40, and 50 seconds as group 1, 2, 3, and 4 respectively. All samples were immersed in distilled water under 37°C temperature for 24 hours as initial treatment. Surface hardness test was done using Vickers Hardness Test with load 50 gf for 20 second. The Data was analyzed with one way ANOVA ( p ≤ 0.05). Results : Using one way anova test ( p ≤ 0.05) shows the mean and standard deviation of the group 1 is 25,900 ± 2,5659VHN; group 2 is 29,800 ± 1,1983 VHN; group 3 is 31,283 ± 0,5037 VHN; group 4 is 36, 183 ± 2,3430 VHN and the obtained value p = 0.000 ( p ≤ 0.05). The mean values and standard deviation were 25.900 ± 2.5659 VHN; 29.800 ± 1.1983 VHN; 31.283 ±0.5037 VHN; 6.183 ± 2.3430 VHN for group 1, 2, 3, and 4 respectively. Statistic analyzed showed a significant different among groups with p value =0.000 ( p < 0.05). Conclusion There are significant differences in surface hardness of hybrid ionomer with different curing time (20, 30,40, and 50 seconds). The longer curing time will increase the surface hardness of hybrid ionomer.