Effect of aging on the translucency of lithium disilicate and zirconia reinforced lithium silicate ceramics: An study.

BACKGROUND

Translucency of dental ceramics have great impact on the esthetic and success of dental restorations. The goal of the study is to investigate the effect of the aging process on the translucency of zirconia-reinforced lithium silicate ceramic material, and lithium disilicate ceramic material made using CAD/CAM and press processes.

METHODS

Thirty disc-shaped specimens with 0.5 mm thickness and 10 mm diameter were fabricated of IPS e.max Press (n = 10), IPS e.max CAD (n = 10), and VITA Suprinity (n = 10) (Vita). All ceramic specimens were fabricated with shade that corresponded to A2 with high translucency (HT) and subjected to measurement of relative translucency parameter (RTP) with a spectrophotometer machine prior to and following thermocycling. The results were analyzed using the one-way ANOVA and Bonferroni methods. To identify any statistically significant change in translucency after thermocycling, paired t-tests were utilized.

RESULTS

The mean ΔRTP after aging was 3.23 ± 0.36, 0.60 ± 0.34, 3.05 ± 0.90 for IPS e.max CAD, IPS e.max Press, and Suprinity respectively. The mean RTP values in IPS e.max CAD and Suprinity decreased significantly after aging (p˂0.05). However, there was no statistically significant difference between the RTP values of the IPS e.max Press before and after aging (p > 0.05).

CONCLUSION

Prior to aging, there was no difference between the three materials in terms of the translucency parameter. However, the translucency of CAD/CAM lithium disilicate and zirconia reinforced lithium silicate was negatively influenced by aging.