Objectives: The aim of this study was to investigate the flexural strength, film thickness, water sorption and solubility of experimental resin luting agents with different organic matrix components. Methods: Five monomer mixtures were obtained, with the following wt:wt ratio of Bis-GMA, TEGDMA and Bis-EMA, respectively: 50:50:0 (R1), 50:30:20 (R2), 50:0:50 (R3), 30:10:60 (R4) and 0:0:100 (R5). Camphorquinone (0.4wt%), N,N-dimethyl-p-toluidine (0.8wt%) and hydroquinone (0.2wt%) were dissolved in each mixture, which were also loaded with 60wt% of silanated glass fillers. Flexural strength was determined in a three-point bending test. Film thickness was measured by placing the materials between optically flat glass plates. Water sorption and solubility were assessed by weight alteration of samples after storage in distilled water, at 37șC, for 7 days. Data were separately submitted to ANOVA and Tukey's test (α=0.05). Results: In the flexural strength (MPa) analysis, no significant differences were detected for R1 (110±15), R2 (124±31), R3 (110±11), R4 (115±19) and R5 (126±33). Film thickness (μm) for R3 (66±15) was significantly higher (p<0.05) than R1 (36±9), R2 (40±11), R4 (42±5) and R5 (39±10). For water sorption (μg/mm³), R5 (.016±.00) presented significantly lower uptake than R1 (.049±.01) and R2 (.031±.01), but similar to R3 (.024±.01) and R4 (.020±.00). Solubility (μg/mm³) results were similar for R1 (.006±.00), R2 (.006±.00), R3 (.008±.00), R4 (.006±.00) and R5 (.009±.00). Conclusion: Materials presenting higher amounts of Bis-EMA showed significantly lower water uptake, while maintaining flexural strength and solubility properties similar to the other cements. However, the mixture containing a 50:50 ratio of Bis-GMA and Bis-EMA presented significantly higher film thickness.

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