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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.

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Aim and background: To describe the treatment of a 55-year-old edentulous female patient using computer-aided design and computer-aided manufacturing (CAD/CAM)milled cobalt chromium (Co-Cr) frameworks infixed complete dentures (FCDs) with a recently introduced possibility of angling the screw channels up to 20 degrees.Case report: Six months after implants placement, implant level impressions were taken from the mandibula and maxilla with individual trays using the open custom tray technique. The verification indexes for fixed complete dentures (FCDs) were fabricated with resin patterns. The master casts were scanned with an extraoral laser scanner and the frameworks were computerized and designed with reference to the verification indexes. The frameworks were fabricated from a Co-Cr alloy using the CAD/CAM-milled fabrication method and the tooth set-up was performed over each framework using prefabricated resin teeth. The FCDs were checked clinically and the prosthetic screws were tightened at the implant level without the interposition of an abutment.Results: Screw-retained FCDs have been successfully utilized to rehabilitate completely edentulous ridges. Conclusion:Connecting the superstructure to the implant using a screw, without the interposition of an abutment, may reduce inaccuracy in laboratory procedures and increase the aesthetic outcome.

SUMMARY Aim:The aim of this study was to evaluate the effect of different curing distances and ceramic materials on the microhardness of dual-cured resin cement. Materials and Methods:The dual-cured resin cement (NX3, Kerr) was polymerized between between lithium disilicate based pressed ceramic (IPS e.max Press (EP)), or three different CAD/CAM materials (Lava Ultimate (LU), e.max CAD (EC), Vita Suprinity (VS)) and a dentine surface with a LED light source from 0, 3 or 6 mm distances for 10 seconds (n=10). The Vickers microhardness (VH) values were recorded immediately after polymerization and after storage at dark in distilled water (24 h/37°C). Three indentations were made both on the top and the bottom surface of each specimen. ANOVA was used to analyse the data. Bonferroni test was used to perform multiple comparisons (p<0.05). Results: The resin cements under the LU specimens have significantly higher VH values compared to the other materials (p<0.05). The bottom surfaces have significantly lower hardness values for all ceramic materials (p<0.05). The VH value of 0 mm curing tip-ceramic distance was significantly higher than the groups of 3 and 6 mm distances (p<0.05). Microhardness values were significantly higher after 24 hours than immediate measurement (p<0.05). Conclusion: Ceramic material and the curing tip-ceramic distance are important factors to be considered for obtaining adequate polymerization.