Use of pre-heated resin for luting of indirect prosthesis: an in vitro study

Composite resins (CRs) are among the most widely used dental materials nowadays. This is due to their physical-chemical and mechanical characteristics similar to dental tissues and can be applied in many procedures. Aiming to improve the use of these composites for luting of indirect prosthesis, several researchers have demonstrated the performance of composite resins when heated, in comparison with conventional resin cements, used as control. Therefore, the aim of this study was to carry out an in vitro study with 10 different types of commercial composite resins compared to a resin cement. The physical-chemical and mechanical properties of the pre-heated resins were evaluated and the control was evaluated at room temperature. The methodology used was based on the analysis of the following parameters: flexural strength, modulus of elasticity and water contact angle. Data were analyzed by ANOVA and Tukey test (α=5%). The preheating had no significant effect on the flexural strength of the 10 tested composite resins (p<0.05). However, preheating increased the modulus of elasticity for Z100 (3M ESPE) e Palfique LX5 (Tokuyama dental) groups while the other composite resins presented similar results in comparison to the resin cement control group (CG) (p<0.05). Regarding the water contact angle, all the composite resins presented results statistically equal to the CG. Therefore, pre-heated composite resins seem to present a favorable performance when considered for indirect cementation.