Comparative Analysis for Selection of Resin Luting Cements Based on Filler Content: An in vitro Study

Context: Resin luting of all-ceramic restorations results in increased performance; however, the strengthening mechanism and the role of the mechanical properties of the resin are not fully understood. Objective: The aim of this study was to investigate the effect of filler content on the flexural properties of resin luting agents and thereby selecting an appropriate resin luting cement. Materials and methods: Three esthetic resin luting agents studied were Calibra (Dentsply); RelyX ARC and Panavia F. Ten beam-shaped specimen (L × W × H: 30 × 8 × 2 mm) were made for each of the material tests carried out. The specimens were stored in distilled water for 24 hours at 37oC. The specimens were then tested for flexural strength (MPa) and flexural modulus (GPa) using the three-point bending method on a universal material testing machine at a cross head speed of 0.5 mm/min. Data obtained were statistically analyzed using ANOVA followed by post-hoc - Tukey’s test with p < 0.05 for statistical significance. Results: Increase in mean strength related to an associated increase in the elastic modulus which in turn was related to the filler loading of the resin luting cements. Conclusion: Strength and performance of resin-cemented allceramic restoration can be enhanced by the use of a resin luting cement having increased filler content. Clinical implications: Resin-composite cements may be most suitable for adhesively bonded restorations, where margins are placed on supragingival enamel, and where ultimate strength and energy absorption are paramount. The selection criteria for a resin cement depends on its flexural strength. To a great extent, the flexural strength is dependent on the filler loading of the resin luting cement.