Volume 11 (2024) | Issue 5
Volume 11 (2024) | Issue 5
Volume 11 (2024) | Issue 5
Volume 11 (2024) | Issue 5
Volume 11 (2024) | Issue 4
Aim: The purpose of the research was to evaluate the fracture resistance of conventional full coverage crowns and two different designs of overlay restorations with margins located 2 and 4 mm above the gingival level. Methodology: CAD/CAM lithium disilicate (IPS e.max CAD for CEREC/HT A1 C14, Ivoclar Vivadent) restorations (15 specimens/group) with 1.5 mm occlusal thickness and 1.0 mm chamfer were designed and fabricated with a chairside CAD/CAM system (CEREC, Dentsply Sirona). The restorations were prepared in three different designs: (1) full coverage crowns, (2) overlays with the margin located 2 mm above the gingiva, and (3) overlays with the margin located 4 mm above the gingiva. Restorations were cemented using conventional resin luting cement (Multilink, Ivoclar Vivadent) then finally loaded with a steel indenter until failure. Scanning electron microscopy observations of fractured surfaces were also conducted. Group results were analyzed with one-way analysis of variance, and the medians were evaluated independently with Kruskal-Wallis.