Objectives: Post-gel polymerization shrinkage is the phase of the overall volumetric shrinkage of a resin composite during which significant stresses are exerted on the surrounding tooth structure. Aim of this study was to compare the post-gel polymerization shrinkage of FiltekTM Silorane with a volumetric polymerization shrinkage of <1% to conventional methacrylate-based composites.
Methods: Samples (approx. 45mg) of TPH3 (TPH3, Dentsply), Grandio (GRA, VOCO), FiltekTM P60 (P60, 3M ESPE), ELS (ELS, Saremco), Tetric EvoCeram (TEC, Ivoclar-Vivadent), QuiXfil (QXF, Dentsply), Premise (PRE, Kerr), and FiltekTM Silorane (SIL, 3M ESPE) were placed on a biaxial strain gauge (CEA-06-032WT-120, Vishay Measurement Systems) and photopolymerized for 40s with a 3M XL 3000 curing light (650mW/cm2). The induced shrinkage strain was monitored for 10min (n=3).
Results: The following table shows the absolute value of post-gel shrinkage strain after 10min in microstrain (µm/m). The standard deviations (SD) are given in parentheses. All data were analyzed by ANOVA and multiple comparisons using the Tukey test (p<0.05). Means with the same letters are statistically the same.
Material | TPH3 | GRA | P60 | ELS | TEC | QXF | PRE | SIL |
µstrain (SD) | 2739.5 (33.8)a | 2388.1 (131.2)b | 2159.7 (45.7)bcd | 2158.4 (58.5)bcd | 2054.7 (76.1)cde | 1951.3 (80.0)de | 1927.1 (94.3)e | 1111.7 (82.5)f |
Conclusion: Multiple statistically significant differences were found. FiltekTM Silorane had the lowest post-gel shrinkage strain of all investigated materials.