Exotherm behavior of the polymer-based provisional crown and fixed partial denture materials.
OBJECTIVE
The objective of this in vitro study was to evaluate the exothermic reaction during polymerization of the polymer-based provisional crown and fixed partial denture materials.


METHODS
Three dimethacrylate-based materials and one monomethacrylate-based material were selected. The specimens were pre-conditioned to 23 degrees C. Temperature changes of the materials during polymerization were recorded in a model test-cavity overlying a type K thermocouple. Peak temperature, time to reach peak temperature and total peak area were determined. The data were statistically analyzed using one-way ANOVA at a significance level of 0.05.


RESULTS
All materials exhibited exotherm release ranging from 5.1 to 12.7 degrees C. Trim gave a peak temperature that was not significantly lower (p > 0.05) than those of Protemp 3 Garant and Luxatemp, but fast set Temphase showed a significantly higher (p < 0.05) peak temperature than the other materials. All materials showed no significant differences (p > 0.05) in the total peak area. Trim showed the slowest exotherm reaction; its time to reach the peak temperature was ca. 10 min after mixing, while ca. 2 min for the other materials.


CONCLUSIONS
The dimethacrylate-based materials (except for fast set Temphase) exhibited no significant differences in peak temperature and total peak area from the monomethacrylate-based material with slower exotherm reaction. A reformulation of the dimethacrylate-based materials could be envisaged to generate a material with a slightly slower setting and a reduced peak temperature.
Kim
Sung-hun
SH
Department of Prosthetic Dentistry, Ewha Womans University, Seoul, Republic of Korea. ksh1250@ewha.ac.uk
Watts
David C
DC
D000180:Acrylic Resins / Q000737:chemistry; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D003794:Dental Restoration, Temporary; D003833:Denture, Partial, Temporary; D006358:Hot Temperature; D008689:Methacrylates / Q000737:chemistry*; D015394:Molecular Structure; D011109:Polymethacrylic Acids / Q000737:chemistry*; D018709:Statistics, Nonparametric; D044366:Transition Temperature
D000180:Acrylic Resins; D003188:Composite Resins; D008689:Methacrylates; D011109:Polymethacrylic Acids; C483029:Temphase; C098586:luxatemp; C091347:vinyl ethyl methacrylate; D017438:Bisphenol A-Glycidyl Methacrylate; C069714:Protemp