Objectives: Optical properties of facial prosthetic elastomers undergo significant changes mainly due to aging. The resulting changes in their appearance are the main reasons of facial prosthesis' replacement.
Purpose: The purpose of this study was to evaluate changes in the translucency parameter (TP) and color (ΔE*) of polydimethylsiloxane (PDMS) maxillofacial elastomers after exposure to 3 different aging conditions (time passage, accelerated "outdoor" aging, and accelerated "indoor" aging).
Materials and Methods: The PDMS prosthetic elastomers tested in this study were low- (LTV) and high-temperature vulcanized (Episil and Mollomed, respectively) in various shades. Color changes (ΔE*) and translucency parameter (TP) were determined in the CIE L*a*b* system using a tristimulus colorimeter. Data were subjected to 2-way analysis of variance followed by Tukey post hoc test. In addition, TP values were analyzed by paired t tests. The significance level of α = 0.05 was set for all tests.
Results: Translucency parameter values for most samples were significantly changed after aging, and ΔE* values were characterized as unacceptable. Both aging procedure and material type affected the changes that occurred. Moreover, dark-shaded samples of both silicone materials revealed significant changes in TP values before and after aging. ΔE* was not significantly different among the same material samples but had significant differences between the 2 materials (Episil and Mollomed). Time passage did not significantly affect TP values contrary to the other 2 accelerated aging procedures. Between outdoor and indoor aging, no significant differences were detected.
Conclusions: Accelerated outdoor and indoor aging caused significant changes in ΔE* and TP values. Significant changes were also detected between material types.
From the *Department of Prosthodontics, Division of Removable Prosthodontics, Dental School, University of Athens; and †Department of Chemical Engineering, National Technical University of Athens, Zografou Campus, Athens, Greece.
Received September 28, 2010.
Accepted for publication January 12, 2011.
Address correspondence and reprint requests to Panagiota N. Eleni, PhD, Zografou Campus, 15780 Athens, Greece; E-mail: firstname.lastname@example.org
The authors report no conflicts of interest.