Does resin cement choice influence the fracture strength of bonded lithium disilicate veneers? An ex vivo study

AIM: The aim of this study was to evaluate and compare the fracture strength of ceramic veneers bonded to natural teeth using different light-cure resin cements. SETTINGS AND DESIGN: An ex vivo study. MATERIALS AND METHODS: Thirty extracted human maxillary anterior teeth were collected and prepared to receive lithium disilicate ceramic veneers, which were allocated into two groups based on the type of resin cement employed for bonding to natural teeth. The specimens were randomly divided into two groups. One group was bonded with Variolink NLC (Ivoclar), whereas the other was bonded with RelyX cement (3M ESPE). Fracture strength was evaluated using a universal testing machine (UTM), with the maximum load required to induce fracture recorded. The tests were conducted under a controlled crosshead speed of 1 mm/min using the UTM, and the maximum load required to cause fracture was recorded for each specimen. STATISTICAL ANALYSIS USED: The Shapiro-Wilk and Kolmogorov-Smirnov tests were employed to assess the data's normality. The variables between the groups were compared using the independent t-test. If P < 0.05, all results were deemed statistically significant. RESULTS: The mean fracture strength of lithium disilicate veneers differed significantly between the two groups. The mean fracture resistance for RelyX was 0.237 ± 0.083 kN, whereas Variolink demonstrated a higher mean of 0.363 ± 0.109 kN. CONCLUSION: Within the limitation of the study, it was concluded that veneers bonded with Variolink NLC cement exhibited higher fracture strength compared to those bonded with RelyX veneer cement.