Cherif A. Mohsen , Raiesa M. Hashem And Abdullah M. Ali,

ABSTRACT

Objectives: The Aim Of This Study Was To Evaluate The Effect Of Accelerated Aging On The Color Stability Of Two Ceramic Materials (one Type Of Hybrid Ceramic And One Type Of Lithium-disilicate Glass Ceramic) Cemented With Different Resin Materials (one Type Of Resin Cement And One Type Of Resin Modified Glass Ionmer Cement)Methods: A Total Of Twenty Molars Were Divided Into Two Groups (n=10) According To Type Of Ceramic Material Cemented On Its Prepared Occlusal Surface: Group 1 For Hybrid Ceramic And Group 2 For Lithium Dislicate Ceramic Each Group Was Randomly Divided Into Two Subgroups (n=5) According To Type Of Cement Used: Subgroup 1 For Resin Cement And Subgroup 2 For Resin Modifiedglass Ionomer Cement. Both Subgroups Were Subjected To Accelerated Aging Process Using Thermocycling System And Color Were Measured Using Spectrophotometer Before Cementation, After Cementation And After Aging. Color Differences (?E) Were Calculated. For Parametric Data; Three-way (ANOVA) Was Used To Analyze The Data, Followed By Mann-Whitney Test, Kruskal- Wallis Test. The Significance Level Was Set At ? 0.05.

Results: The L* A* B* Values Of The Tested Materials Were Affected By Both Ceramic Materials And Cement Types After Aging. Samples Of Hybrid Ceramic Cemented With Resin Modifiedglass Ionmer Cement Were With The Most DE Value Of The Tested Samples. Samples Of Lithium Dislicate Cemented With Resin Cement Were With The LeastDE Value Of The Tested Samples.Conclusion: Variation In Used Cement Type Had More Effect On Color Stability Than Variation In Used Ceramic Type. Lithium Dislicate Ceramic Samples Cemented With Resin Cement Was The Most Color Stable After Thermocycling.