Micro-computed tomography evaluation of volumetric polymerization shrinkage and degree of conversion of composites cured by various light power outputs

作者：Atria Pablo J^*; Sampaio Camila S; Caceres Eduardo; Fernandez Jessica; Reis Andre F; Giannini Marcelo; Coelho Paulo G; Hirata Ronaldo

来源：Dental Materials Journal, 2018, 37(1): 33-39.

DOI：10.4012/dmj.2016-430

• Shrinkage
• Composite
• Polymerization
• Light-curing
• Computed-tomography

This study evaluated the influence of different light-curing modes on the volumetric polymerization shrinkage and degree of conversion of a composite resin at different locations using micro-computed tomography and Fourier transform infrared spectroscopy (FTIR). Specimens were divided into 4 groups based on the light-curing mode used (Bluephase 20i): 1 -High (1,200 mW/cm(2)); 2 -Low (650 mW/cm(2)); 3 -Soft-start (650-1,200 mW/cm(2)); and 4 -Turbo (2,000 mW/cm(2)). Degree of conversion was calculated by the measurement of the peak absorbance height of the uncured and cured materials at the specific wavenumbers, and was performed by FTIR 48 h after curing resin samples. Degree of conversion was analyzed using two-way ANOVA. No significant differences were observed independent of the region of the restoration investigated (p>0.05). Different curing modes did not influence volumetric shrinkage neither degree of conversion of class I composite resin restorations.

• 出版日期2018-2