Objective  To analyze the influence of three pigment incorporation methods on color change, dimensional stability, and detail reproduction of the MDX4–4210 and A-2186 silicones. Materials and Methods  The A-2186 and MDX4–4210 silicones were used for preparation of samples, with the incorporation of bronze, black and pink pigments, usingconventional, mechanical, and industrial incorporation methods. Samples were submitted to the initial readings of color ( n = 10; 22-mm diameter × 2-mm thickness), detail reproduction, and dimensional stability ( n = 10; 30-mm diameter × 3-mm thickness). Readings were also taken at the end of 252, 504 and 1,008 hours of aging cycles. Results  Quantitative data were evaluated by ANOVA and Tukey test, with a level of significance of 5%. The mechanical and industrial methods caused smaller color changes of all samples compared with the conventional method ( p < 0.05). In most cases, the mechanical and industrial methods caused less samples’ contraction than the conventional method after aging ( p < 0.05). The color change values increased progressively in each aging period for all samples ( p < 0.05). The contraction values increased progressively in each aging period for all samples ( p < 0.05). In the qualitative analysis of detail reproduction, all samples presented full reproduction of the three grooves, with accurate angles, initially and after the aging periods. Conclusions  The industrial and mechanical methods showed the best results for color and dimensional stability. Despite the statistical differences, all pigment incorporation methods generated acceptable dimensional and color changes of the MDX4-4210 and A-2186 silicones, regardless of the pigment and aging. In addition, the detail reproduction was satisfactory after aging periods in all cases of this study, showing the excellent quality of the A-2186 and MDX4–4210 silicones.

Some evidence suggests that the surface roughness of ocular prostheses can influence interactions with micro-organisms, with greater prejudicial consequences, such as the establishment of biofilms, which could lead to infections. Thus, it becomes extremely important to identify the micro-organisms present on the acrylic surfaces of ocular prostheses, as well as the microbiota of the anophthalmic cavity and contralateral eye of wearers of the same, so that subsequent control measures promote the homeostatic maintenance of the ocular region.

Objective. To evaluate the influence of different pigmentations and accelerated aging on the hardness and tear strength of the A-2186 and MDX4-4210 silicones. Materials and Methods. The samples A-2186 and MDX4-4210 were manufactured without and with pigmentations (black, bronze, and pink). For the Shore A hardness test, 80 samples of each silicone were fabricated, and for the tear strength test, 320 samples of each silicone were fabricated. Eight groups were created for each test (n = 10). These tests were performed before and after 252, 504, and 1008 hours of aging. Three-way repeated-measures analysis of variance and the Tukey test were performed (α = 0.05). Results. The A-2186 silicone showed higher hardness and tear strength when compared with the MDX4-4210 silicone p<0.05, except in the hardness of the A-2186 and MDX4-4210 groups without pigmentation after 1008 hours p>0.05. All hardness values were between 25 and 35 units, regardless of the silicone type, period, and pigmentation (or no pigmentation). In most situations, the hardness of silicones used increased after 252 hours p<0.05. The nonpigmented MDX4-4210 group and all A-2186 groups showed an increase in tear strength after 252 hours p<0.05. For the nonpigmented MDX4-4210 group, from 252 to 1008 hours, there was no change in tear strength p>0.05. All pigmented MDX4-4210 groups showed no change in tear strength from 0 (initial) to 1008 hours of aging p>0.05. In all A-2186 groups, from 252 to 504 hours, there was a reduction in tear strength p<0.05, and from 504 to 1008 hours, there was an increase in tear strength p<0.05, except in the bronze A-2186 group p>0.05. Conclusion. In most situations, the A-2186 silicone showed significantly higher values of hardness and tear strength than the MDX4-4210 silicone. All hardness values were considered clinically acceptable. Accelerated aging could increase, decrease, or not significantly change the hardness and tear strength of the silicones used. The results of hardness and tear strength suggest that MDX4-4210 was more influenced by the presence of pigmentation after aging.

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