Setting Reaction of Dental Resin-Modified Glass Ionomer Restoratives as a Function of Curing Depth and Postirradiation Time. (3rd August 2015)

• Record Type: Journal Article
• Authors: Kim, Young Kyung; Kim, Kyo-Han; Kwon, Tae-Yub
• Other Names: Zhang Qingrui Academic Editor.
• Is Part Of: Journal of spectroscopy. Volume 2015(2015)
• Publication Date: 2015-08-03
• Subjects: Spectrum analysis -- Periodicals; 543.505
• DOI: 10.1155/2015/462687
• Languages: English
• ISSNs: 2314-4920

Abstract

Abstract : Specular reflectance Fourier transform infrared (SR-FTIR) spectroscopy was used to study the setting reaction of dental resin-modified glass ionomer (RMGI) restoratives as a function of curing depth and postirradiation time. Two light-cure and one tri-cure RMGI materials were selected and used according to the manufacturers' instructions. Samples were prepared by filling the mixed materials into custom-made molds and then light-irradiating using a dental curing light. The degree of conversion and the extent of acid-base reaction of the materials at different depths (0, 1, 2, and 4 mm) and postirradiation times (10 min, 1 day, and 7 days) were determined using SR-FTIR spectroscopy in conjunction with the Kramers-Kronig (K-K) transformation. The setting reaction was also investigated using microhardness measurements. The results showed that the depth of cure increased over time by the continuous acid-base reaction rather than photopolymerization or chemical polymerization. Microhardness tests seemed less suitable for studying the setting reaction as a function of postirradiation time, probably due to softening from the humidity. Analysis using specular reflectance in conjunction with the K-K algorithm was an easy and effective method for monitoring the setting reaction of dental RMGI materials.