Temperature changes under demineralized dentin during polymerization of three resin-based restorative materials using QTH and LED units.
10.5395/rde.2014.39.3.155
- Author:
Sayed Mostafa MOUSAVINASAB
1
;
Maryam KHOROUSHI
;
Mohammadreza MOHARRERI
;
Mohammad ATAI
Author Information
1. Torabinejad Dental Research Center and Department of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
- Publication Type:In Vitro ; Original Article
- Keywords:
Degree of conversion;
Demineralization;
Dentin;
Light-curing unit;
Light polymerization;
Temperature rise
- MeSH:
Dental Pulp Cavity;
Dentin*;
Humans;
Molar;
Polymerization*;
Polymers*;
Quartz;
Spectroscopy, Fourier Transform Infrared;
Tooth;
Tungsten
- From:Restorative Dentistry & Endodontics
2014;39(3):155-163
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVES: Light-curing of resin-based materials (RBMs) increases the pulp chamber temperature, with detrimental effects on the vital pulp. This in vitro study compared the temperature rise under demineralized human tooth dentin during light-curing and the degrees of conversion (DCs) of three different RBMs using quartz tungsten halogen (QTH) and light-emitting diode (LED) units (LCUs). MATERIALS AND METHODS: Demineralized and non-demineralized dentin disks were prepared from 120 extracted human mandibular molars. The temperature rise under the dentin disks (n = 12) during the light-curing of three RBMs, i.e. an Ormocer-based composite resin (Ceram. X, Dentsply DeTrey), a low-shrinkage silorane-based composite (Filtek P90, 3M ESPE), and a giomer (Beautifil II, Shofu GmbH), was measured with a K-type thermocouple wire. The DCs of the materials were investigated using Fourier transform infrared spectroscopy. RESULTS: The temperature rise under the demineralized dentin disks was higher than that under the non-demineralized dentin disks during the polymerization of all restorative materials (p < 0.05). Filtek P90 induced higher temperature rise during polymerization than Ceram.X and Beautifil II under demineralized dentin (p < 0.05). The temperature rise under demineralized dentin during Filtek P90 polymerization exceeded the threshold value (5.5degrees C), with no significant differences between the DCs of the test materials (p > 0.05). CONCLUSIONS: Although there were no significant differences in the DCs, the temperature rise under demineralized dentin disks for the silorane-based composite was higher than that for dimethacrylate-based restorative materials, particularly with QTH LCU.
