Evaluating the final color of restorations with three CAD/CAM core materials (Cr-Co, Zirconia, Peek), veneered by two methods (indirect CAD/CAM composite, heat-pressed ceramics)

Abstract

Abstract Background This study aimed to evaluate the final color of restorations with three different core materials (Cr-Co, Zirconia, PEEK) veneered with heat-pressed ceramic or CAD/CAM composite. Methods Forty core disks (10 mm× 10mm× 0.5 mm) were milled from Zirconia and Cr-Co blocks and were veneered with either A2 shade CAD/CAM composite resin or heat-press ceramic. (n=10) Ten disks from PEEK blocks were only veneered with composite resins. A2 shade veneer material with 2mm thickness served as control for color evaluation. Color parameter were measured by spectrophotometer. Results The mean color differences of Cr-Co, Zirconia and PEEK samples veneered with composite were 2.91(±0.45), 3.24 (±0.33) and 2.75 (±0.35) and for Cr-Co and Zirconia in ceramic groups were 6.46(±0.32) and 1.97(±0.19) respectively. One-way ANOVA and Tukey's post hoc test showed a significant difference between the core groups veneered with ceramic (P value=0.000). The type of core material in the composite veneered samples, however, did not make a significant difference. (P value=0.186). All groups except for Cr-Co-ceramic showed clinically acceptable results (ΔΕ<3.7). Conclusion Type of core material presented significant effect on the final color of restorations when ceramic was used as a veneer material. Conversely, the final color of composite veneer restorations is not affected by the core type. CAD/CAM composites can provide adequate color coverage for different core materials without exceeding a minimum clinically acceptable thickness