IADR Abstract Archives
Volumetric polymerization shrinkage, microhardness and depth of cure of bulk-fill composites.
Objectives: To compare the volumetric polymerization shrinkage (VS), Vickers hardness (HV) and depth of cure (DOC) profiles of three bulk fill composites with a conventional composite.
Methods: Three bulk fill composites; Tetrin N CeramBulk Fill (TBF), SonicFill (SF), Beautifil Bulk Restorative (BBR) and a conventional composite Tetric N Ceram (TNC) were compared. The volumetric polymerization shrinkage of the composites was measured using a video imaging device (AcuVol, BiscoInc; n:10). For HV and DOC, three specimens of each composite were prepared using teflon molds with 5mm in diameter and 8mm in depth and polymerized according to the manufacturer’s instructions (Demi Ultra). All specimens were stored at 37oC for 24 hours in distilled water before the measurements. HV was evaluated for each specimen as a function of depth of material at 0.1mm intervals (Buehler). DOC was calculated as the 80% hardness drop-off. One way ANOVA, Pearson Correlation and Kruskal Wallis tests were performed for the statistical analyses (p<0.05).
Results: There were statistically significant differences between the composites for the tested parameters (p<0.005). BBR showed the lowest VS (1.68±0.17) while TNC resulted in the highest (2.49±0.27) among the other composites (p<0.01). The maximum HV ranged from 60.87 to 114.37 N/mm2. SF exhibited the highest, whereas TNC showed the lowest HV (p<0.01). BBR showed the highest DOC corresponding to 80% of max HV. There were no statistically significant correlations between HV and VS values (p>0.05).
Conclusions: Bulk-fill composites presented lower volumetric polymerization shrinkage, higher Vickers hardness and depth of cure than the conventional composite.
Methods: Three bulk fill composites; Tetrin N CeramBulk Fill (TBF), SonicFill (SF), Beautifil Bulk Restorative (BBR) and a conventional composite Tetric N Ceram (TNC) were compared. The volumetric polymerization shrinkage of the composites was measured using a video imaging device (AcuVol, BiscoInc; n:10). For HV and DOC, three specimens of each composite were prepared using teflon molds with 5mm in diameter and 8mm in depth and polymerized according to the manufacturer’s instructions (Demi Ultra). All specimens were stored at 37oC for 24 hours in distilled water before the measurements. HV was evaluated for each specimen as a function of depth of material at 0.1mm intervals (Buehler). DOC was calculated as the 80% hardness drop-off. One way ANOVA, Pearson Correlation and Kruskal Wallis tests were performed for the statistical analyses (p<0.05).
Results: There were statistically significant differences between the composites for the tested parameters (p<0.005). BBR showed the lowest VS (1.68±0.17) while TNC resulted in the highest (2.49±0.27) among the other composites (p<0.01). The maximum HV ranged from 60.87 to 114.37 N/mm2. SF exhibited the highest, whereas TNC showed the lowest HV (p<0.01). BBR showed the highest DOC corresponding to 80% of max HV. There were no statistically significant correlations between HV and VS values (p>0.05).
Conclusions: Bulk-fill composites presented lower volumetric polymerization shrinkage, higher Vickers hardness and depth of cure than the conventional composite.