Effects of saliva and nasal secretion on some physical properties of four different resin materials.

OBJECTIVE Aim of this study was to evaluate possible effects of saliva and nasal secretion on some physical properties, such as sorption, solubility, surface hardness and colour change on four different resin-based materials over a certain time period. METHODS A total of 128 disc-shaped specimens with a diameter of 50 mm and thickness of 0.5 mm were tested to evaluate sorption and solubility (ISO-1567). The specimens were stored in different solutions prior to testing. Surface hardness measurements were performed by using a Vickers hardness testing machine. A total of 20 cylinder-shaped test specimens with a diameter of 13 mm and thickness of 1 mm were prepared to evaluate colour change (ΔE). Analysis of variance was used to determine significant differences among groups. Paired t and Tukey Post-Hoc tests were performed to investigate significant differences among subgroups at all time intervals (p<0.05). RESULTS It was found that while the percentage absorption value at T7 (7 days) of the A groups stored in artificial saliva+nasal secretion were the highest (0.057±0.119), the percentage absorption value at T15 (15 days) of the D groups stored in artificial nasal secretion were the lowest (0.013±0.09). Besides, it was found that the percentage solubility value at T30 (30 days) of VLC groups stored in artificial nasal secretion were the highest (0.016±0.003), and the percentage solubility value at T1(1 day) of the D groups stored in distilled water were the lowest (0.01±0.02). While the highest hardness value was of T0 (Dry) in group H (36.19±1.35), the lowest hardness value was of T0 in group D (9.83±2.48). When ΔE values analysed for each group, VLC group showed the highest values (23.78±5.05) (p<0.05), group D showed the lowest values (9.06±2.82) in time (between the T0 and T30). CONCLUSION The new polyamide resin was observed to show better physical properties when compared with other materials.