ISSN:
1365-2842
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
summary The purpose of this study was to evaluate the polymerization shrinkage of three orthodontic adhesive resins when polymerized with a high-energy plasma arc light (1340 mW cm−2) and a conventional halogen light (500 mW cm−2), and to correlate the polymerization shrinkage with the degree of conversion. To equalize the total light energy delivered to the adhesive resin, irradiation time was varied between 3 or 6 s for a plasma arc-curing unit, and 8 or 16 s for a halogen light-curing unit. The polymerization shrinkage of adhesive resins during the light-curing process was measured using a computer-controlled mercury dilatometer and the degree of conversion was measured using Fourier transform infrared spectroscopy. A plasma arccuring unit produced significantly lower polymerization shrinkage than a halogen light-curing unit when the equivalent total light energy was irradiated to the orthodontic adhesive resins (P 〈 0·05). The magnitude of polymerization shrinkage was significantly different depending on the kind of adhesive resins (P 〈 0·05), but there was no significant correlation between the filler fraction and the polymerization shrinkage (r2 = 0·039). There was strong correlation (r2 = 0·787) between the polymerization shrinkage and the degree of conversion with a halogen light-curing unit, but poor correlation (r2 = 0·377) was observed with a plasma arc-curing unit.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2842.2004.01301.x
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