INFLUENCE OF DIFFERENT METHODS OF PIGMENT INCORPORATION ON CHROMATIC STABILITY OF FACIAL ELASTOMER
Marcela Borgui Paulini, DDS, MSc, Daniela Micheline dos Santos, MS, PhD, Emily V. Freitas da Silva, Rodrigo Antonio de Medeiros, DDS, MSc, Murilo C. Bento Laurindo-Junior DDS, MSc, Adhara S. Nobrega, DDS, MSc, Aldiéris Alves Pesqueira, MS, PhD and Marcelo Coelho Goiato, MS, PhD*
Statement of the Problem: Color alteration, which generally occurs due to the degradation and pigmentation of the prosthesis, is one of the principal factors related to limitations of treatments with facial prostheses. Objective: Evaluate two incorporation methods of pigment mixtures and the influence on the color stability of MDX4-4210 elastomers, as well as qualitatively evaluate the dispersion of the pigment by means of a scanning electron micros-copy (SEM) associ-ated with an energy dispersive spectrometer (EDS). Materials and Methods: Twenty-two facial elastomer specimens were fabricated and distributed in two groups: conventional laboratory incorporation and mechanical incorporation. Twenty specimens were submitted to a chromatic stability reading (ΔE and L*, a*, and b* coordinates) and two speci-mens were submitted to the SEM/EDS. Tests were performed before and after the accelerated aging for 1008 hours. The color alteration (ΔE) data were submitted to Student’s t-test (α=.05). Data for the L*, a*, and b*coordinates were submitted to the two-way repeated measures variance analysis (ANO-VA) and the Tukey test (α=.05). The qualitative data from SEM and EDS were compared visually. Results: The results demonstrated that there was a decrease in the L* coordinate value in the conventional incorporation method after the accelerated aging (p=.002), while there was an increase in the mechanical method (p<.001). For the a* (p<.001) and b* (p<.001) coordinate values, a decrease of val-ues occurred for both methods of incorporation after aging. Conclusions: The incorporation methods of the pigment mixture with silicone interfered in the L*, a*, and b* coordinates. However, the chromatic stability (ΔE) of the material was similar for both incorporation methods.
Keywords: Maxillofacial Prosthesis, Silicone Elastomers, Coloration Prosthesis.
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