Setting Reaction of Dental Resin-Modified Glass Ionomer Restoratives as a Function of Curing Depth and Postirradiation Time
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 accor...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Hindawi Limited
2015-01-01
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Series: | Journal of Spectroscopy |
Online Access: | http://dx.doi.org/10.1155/2015/462687 |
Summary: | 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. |
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ISSN: | 2314-4920 2314-4939 |