Fracture resistance of prepared premolars restored with bonded new lab composite and all‐ceramic inlay/onlay restorations: Laboratory study

• Published in: Journal of esthetic and restorative dentistry 2018-05, Vol.30 (3), p.229-239
• Main Authors: Wafaie, Ramy Ahmed, Ibrahim Ali, Ashraf, Mahmoud, Salah Hasab
• Format: Article
• Language: English
• Subjects: all ceramic; Ceramics; Composite materials; Dental caries; Dental restorative materials; Dentistry; fracture resistance; inlay/onlay restorations; lab composite; Lithium; Maxilla; Premolars; Statistical analysis; Studies; Teeth; Yttrium; Zirconia
• ISSN: 1496-4155; 1708-8240
• DOI: 10.1111/jerd.12364

Objectives To assess the influence of new light curing lab composite, lithium‐disilicate glass‐ceramic and yttrium‐stabilized zirconia‐based ceramic on the fracture resistance of maxillary premolars with class II inlay and onlay preparations. Methods Seventy sound maxillary premolars were divided randomly into seven main groups. The first group was left intact (control group). The remaining six groups were prepared with inlay and onlay cavities and restored with lab composite (SR Nexco), lithium‐disilicate glass‐ceramic (IPS e.max Press) and yttrium‐stabilized zirconia‐based ceramic (ICE Zirkon). The restorations were cemented with luting resin composite (Variolink N). All specimens were thermocycled 5000 cycles between 5°C ± 2°C and 55°C ± 2°C and were then cyclic loaded for 500 000 cycles. The specimens were subjected to a compressive load in a universal testing machine using a metal sphere until fracture occurred. The results were analyzed by 2‐way ANOVA and Tukey HSD post hoc tests. The level of significance was set at P  .05). However, statistically significant differences were found among the means of control group and the groups restored with lab composite inlays, lab composite onlays, pressable glass ceramic inlays and pressable glass ceramic onlays (P