Evaluation of the Adaptation and Fracture Resistance of Three CAD–CAM Resin Ceramics: An In vitro Study

Abstract

Aim:The internal fit and resistance to fracture of resin ceramics are to be evaluated compared to that of lithium disilicate as the control group. Materials and methods: Four groups of 20 crowns each (GC Cerasmart, Vita Enamic, Coltène Brilliant Crios, and e.max CAD) were cemented on identical metal dies. Marginal gaps were measured before cementation and load to fracture was applied after cementation, half of each group was thermodynamically aged (3,000 cycles of 5° to 55° immersion followed by 200,000 cycles of 100 N load), finally the crowns were loaded until fracture in a universal testing machine. Statistical package for social sciences (SPSS) package 23 was used for statistical work. Results: Marginal gaps ranged between 68.5 ± 23.8 µm and 87 ± 29.1 µm while occlusal gaps ranged from 220.7 ± 33.3 µm to 275.5 ± 46.5 µm and were not significantly different between groups. Fracture loads ranged from 633.8 ± 127.3 N to 1596.4 ± 497.7 N with lithium disilicate glass ceramics (LDGCs) and Enamic having higher values than resin nano-ceramics (RNCs). The fracture resistance was more related to material than aging and gap value. Conclusion: The margin adaptation of resin ceramics was comparable to lithium disilicate with no significant difference. Lithium disilicate showed a higher resistance than resin ceramics and there was a higher resistance to fracture for polymer-infiltrated ceramic-network (PICN) than RNCs. Clinical significance: Resin ceramics can have marginal adaptation and fracture resistance within clinical acceptance; therefore, they can be a good chair-side solution achieved in a single appointment session.

Marginal adaptation and fracture resistance of milled and 3D-printed CAD/CAM hybrid dental crown materials with various occlusal thicknesses

“…Conversely, a study by Azarbal et al [10], in 2017, reported that VE crowns fabricated using the CEREC milling system showed marginal adaptation superior to that of lithium disilicate crowns [10]. In this study, all the hybrid material crowns produced MG values within the clinically acceptable range [9] similar to previous studies [25,26].…”

Comparative evaluation of fracture resistance of different CAD/CAM fabricated endocrowns - in vitro study

“…A study conducted by Altieret al (17) reported that lithium disilicate (IPS e.max CAD) posterior endocrowns exhibited higher fracture strength compared to resin nanocomposite materials such as Solidex and Grandia when subjected to axial load. Similarly, Naffah et al (19) proved that lithium disilicate and Enamic restorations had higher fracture resistance when they compared to Brilliant Crios and Cerasmart restorations.…”