Abstract
STATEMENT OF PROBLEM
The degree of conversion may influence the ultimate mechanical and physical properties of provisional crown and fixed partial denture materials. The high levels of the unreacted residual monomer may cause deleterious effect on the properties.
PURPOSE
The purpose of this study was to measure the degree of conversion of bis-acrylic based provisional crown and fixed partial denture materials by using an infrared spectroscopic method.
MATERIAL AND METHODS
Chemically activated three bis-acrylic based provisional crown and fixed partial denture materials, LuxaTemp [DMG, Hamburg, Germany], fast set TemPhase [Kerr, Orange, CA, USA] and Protemp 3 Garant [3M-ESPE, St Paul, MN, USA], were investigated by Fourier transform infrared spectrometry (FTIR). The FTIR spectra of the materials tested were immediately obtained after mixing. The specimens were stored under dry conditions and at 23oC for 24 hours, and then the spectra of the materials were also obtained. The degree of conversion (%) was calculated from the spectrum of the absorbance between the aliphatic double bond at 1637 cm-1 and the aromatic double bond at 1608 cm-1 using the baseline method. The data were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05.
RESULTS
The mean value and standard deviation of the degree of conversion were 52.5 % ± 1.1 %, 50.3 % ± 0.8 %, and 42.3 % ± 4.9 % for LuxaTemp, Protemp 3 Garant and fast set TemPhase, respectively. There was no significant difference between LuxaTemp and Protemp 3 Garant, whereas there was a statistically difference between Protemp 3 Garant and fast set TemPhase, and LuxaTemp and fast set TemPhase (P < .05).
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