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Objective This study aimed to evaluate the effect of artificial accelerated aging (AAA) on color stability, surface roughness, and microhardness of three laminate veneer (LV) materials. Materials and Methods Specimens of ceramic LV (CLV‐IPS E.max Press), hand‐layered composite LV (hand‐layered laminate veneer [HLV]‐Tetric N‐Ceram), and prefabricated composite LV (prefabricated laminate veneer [PLV]‐Componeer Coltene) were prepared as discs (n = 10). CIE L*, a*, and b* color coordinates, the Vickers microhardness, and surface roughness were measured 24 hours after preparation and reevaluated after aging for 300 hours in an ultraviolet (UV)‐AAA system (Ci35 Weather‐Ometer). Color difference (CIEDE2000 [ΔE00]) was calculated. Data were statistically analyzed with the Shapiro‐Wilk test and the Kruskall‐Wallis test followed by the Mann‐Whitney U tests (α = .05). Results All of the LV groups showed significant differences in ΔE00 after AAA (P < .001). Comparing the color changes of the HLVs with the PLVs, no significant difference could be found (P = .705). There was a statistically significant difference in the means of changes in microhardness among the LVs materials (P < .001). The changes in surface roughness results showed a significant difference after AAA in all the LVs (P < .001). Conclusions Within the limitations of this in vitro study, the color stability, the microhardness, and surface roughness of tested LVs were influenced by AAA. Clinical significance The prefabricated composite LV system does not replace the individualized ceramic LV technique, but rather offers an alternative to hand‐layered LVs, which is delicate and time‐consuming technique.

Chipping of the veneering porcelain is often reported in the literature. Intraoral repair of chipped veneering porcelain provides an option when the restoration cannot be removed and replaced. This in vitro study investigated the bond strength of two porcelain repair methods to the zirconia ceramic after different aging conditions. A total of 120 (Vita InCeram YZ) samples were divided into two main groups according to the different repair methods (n = 60). The first method was using a porcelain repair kit (Bisco), and the second method was repairing with a universal adhesive (Single Bond Universal Adhesive) and a composite resin (Z100). Each group was divided into two subgroups (n = 30) according to surface modification (with or without airborne particle abrasion). Each group was then divided into three subgroups (n = 10) depending on aging conditions. Shear bond strength tests were performed to measure the adhesion strength between composite and zirconia surfaces. Statistical analysis was performed with 3‐way ANOVA, followed by Tukey HSD test (α = 0.05). Surface conditioning by airborne particle abrasion affected the strength values in the repair kit group compared with conventionally repaired group. Conventionally repaired group showed statistically significant higher bond strength values than repair kit group.

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