The efficiency of adding nanoparticles to silicone protection has proven to prevent color degrada... more The efficiency of adding nanoparticles to silicone protection has proven to prevent color degradation. However, reports of other physical property changes in facial silicone are scarce. The purpose of this in vitro study was to evaluate the influence of adding nanoparticles on the hardness, tear strength, and permanent deformation of a facial silicone. Specimens were made for each test, with 140 for the hardness test, 140 for the permanent deformation test, but 280 for the rupture test. This higher number was due to the fact that the first 140 specimens were ruptured and unusable after the initial reading. ZnO, BaSO4, and TiO2 nanoparticles at concentrations of 1% and 2% of silicone were used, as well as specimens without nanoparticles that consisted of only oil paint and of only silicone. Outcomes were measured before and after 1008 hours of accelerated aging. Data were analyzed by nested analysis of variance (ANOVA) and Tukey honest significant differences test (α=.05). Results sh...
Objective The aim of the study is to evaluate the effect of extrinsic pigmentation on the dimensi... more Objective The aim of the study is to evaluate the effect of extrinsic pigmentation on the dimensional stability, hardness, detail reproduction, and color of a silicone after thermocycling. Materials and Methods Sixty samples of MDX4–4210 silicone (Dow Corning Corporation Medical Products) with intrinsic pink pigment (H-109-P, Factor II) and intrinsic opacifier (TiO) were fabricated. Two groups were created: Group 1—only intrinsic pigmentation (H-109P, Factor II + TiO) (Control); and Group 2—intrinsic (H-109P, Factor II + TiO) and extrinsic (Tan FE - 215, Factor II) pigmentation. The following tests were performed for each group: dimensional stability, Shore A hardness, detail reproduction, and color. Readings for the tests were taken before and after thermocycling (2,000 cycles). For dimensional stability and hardness, two-way analysis of variance (ANOVA) was used. One-way ANOVA was used for the color test. In case of significant statistical difference, the Tukey test was applied (p...
Objective The aim of this study is to evaluate the color alteration and shore A hardness of a med... more Objective The aim of this study is to evaluate the color alteration and shore A hardness of a medical silicone with extrinsic pigmentation, before and after accelerated aging. Materials and Methods Twenty samples (Silastic Q7–4735) were made with an intrinsic pigmentation. This intrinsic pigmentation was composed of a pink pigment (H-109-P, Factor II) and an opacifier (ZnO). All samples had standardized dimensions (45-mm diameter and 2-mm thickness). Half of the 20 samples manufactured subsequently received an extrinsic pigment (Tan FE–215, Factor II). Therefore, two groups were created (n = 10): Group 1, group with intrinsic pigmentation and without extrinsic pigmentation (control) and Group 2, group with intrinsic and extrinsic pigmentation. Samples were submitted to color and Shore A hardness tests, before and after 1,008 hours of aging. Statistical Analysis Color alteration data were submitted to Student’s t-test (α = 0.05). Shore A hardness data were submitted to two-way analys...
This review presents a classification system for maxillofacial prostheses, while explaining its t... more This review presents a classification system for maxillofacial prostheses, while explaining its types. It also aims to describe their origin and development, currently available materials, and techniques, predicts the future requirements, and subsequently discusses its avenues for improvement as a restorative modality. A literature search of the PubMed/Medline database was performed. Articles that discussed the history, types, materials, fabrication techniques, clinical implications, and future expectations related to maxillofacial prostheses and reconstruction were included. Fifty-nine articles were included in this review. Maxillofacial prostheses were classified as restorative or complementary with subclassifications based on the prostheses finality. The origin of maxillofacial prostheses is unclear; however, fabrication techniques and materials have undergone several changes throughout history. Currently, silicones and acrylic resins are the most commonly used materials to fabri...
Objectives: The aim of this study was to evaluate the influence of different polymerization metho... more Objectives: The aim of this study was to evaluate the influence of different polymerization methods of acrylic resin for ocular prostheses on the subcutaneous tissue inflammatory response of rats. Methods: Samples were prepared by: water bath (WB), microwave energy (MW), or autopolymerization (AP) (n=20/group). The inflammatory response (cell count and immunohistochemical analysis of IL-1β, IL-6, TNF-α, IL-17, and MIP-3α) was analyzed by the implantation of a sample from each group in the subcutaneous tissue of 20 Wistar rats, and evaluated after 7, 15, 30, and 60 days. Quantitative and qualitative data were submitted to ANOVA and Tukey test (p<0.05) and to visual comparison, respectively. Results: There was a moderate inflammatory infiltrate for MW and AP groups and a light infiltrate for the WB group after 7 days. The inflammatory infiltrate and the immunolabeling of tested targets decreased gradually during the 60 days. The AP group had the highest immunolabeling of TNF-α (7 d...
Objectives The aim of this study was to verify during facial expressions (“happy,” “sad,” “fearfu... more Objectives The aim of this study was to verify during facial expressions (“happy,” “sad,” “fearful,” “angry,” “surprised,” and “disgusted”) if: (1) there would be difference in the electromyography (EMG) of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles on the normal side (NS) compared with the affected side (AS) (without the use of an ocular prosthesis) in individuals with unilateral absence of the eyeball, and (2) the rehabilitation with a new ocular prosthesis would affect the EMG of the muscles studied on the AS in these individuals. Materials and Methods Thirteen individuals, without temporomandibular disorder, with good health, with unilateral absence of the eyeball (the eye must have been removed by evisceration or enucleation), and users or nonusers of an ocular prosthesis were included. EMG of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles was performed during rest and facial expressions (“happy,” “sad,” “fearful,” “an...
Objective To analyze the influence of three pigment incorporation methods on color change, dimens... more 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 efficiency of adding nanoparticles to silicone protection has proven to prevent color degrada... more The efficiency of adding nanoparticles to silicone protection has proven to prevent color degradation. However, reports of other physical property changes in facial silicone are scarce. The purpose of this in vitro study was to evaluate the influence of adding nanoparticles on the hardness, tear strength, and permanent deformation of a facial silicone. Specimens were made for each test, with 140 for the hardness test, 140 for the permanent deformation test, but 280 for the rupture test. This higher number was due to the fact that the first 140 specimens were ruptured and unusable after the initial reading. ZnO, BaSO4, and TiO2 nanoparticles at concentrations of 1% and 2% of silicone were used, as well as specimens without nanoparticles that consisted of only oil paint and of only silicone. Outcomes were measured before and after 1008 hours of accelerated aging. Data were analyzed by nested analysis of variance (ANOVA) and Tukey honest significant differences test (α=.05). Results sh...
Objective The aim of the study is to evaluate the effect of extrinsic pigmentation on the dimensi... more Objective The aim of the study is to evaluate the effect of extrinsic pigmentation on the dimensional stability, hardness, detail reproduction, and color of a silicone after thermocycling. Materials and Methods Sixty samples of MDX4–4210 silicone (Dow Corning Corporation Medical Products) with intrinsic pink pigment (H-109-P, Factor II) and intrinsic opacifier (TiO) were fabricated. Two groups were created: Group 1—only intrinsic pigmentation (H-109P, Factor II + TiO) (Control); and Group 2—intrinsic (H-109P, Factor II + TiO) and extrinsic (Tan FE - 215, Factor II) pigmentation. The following tests were performed for each group: dimensional stability, Shore A hardness, detail reproduction, and color. Readings for the tests were taken before and after thermocycling (2,000 cycles). For dimensional stability and hardness, two-way analysis of variance (ANOVA) was used. One-way ANOVA was used for the color test. In case of significant statistical difference, the Tukey test was applied (p...
Objective The aim of this study is to evaluate the color alteration and shore A hardness of a med... more Objective The aim of this study is to evaluate the color alteration and shore A hardness of a medical silicone with extrinsic pigmentation, before and after accelerated aging. Materials and Methods Twenty samples (Silastic Q7–4735) were made with an intrinsic pigmentation. This intrinsic pigmentation was composed of a pink pigment (H-109-P, Factor II) and an opacifier (ZnO). All samples had standardized dimensions (45-mm diameter and 2-mm thickness). Half of the 20 samples manufactured subsequently received an extrinsic pigment (Tan FE–215, Factor II). Therefore, two groups were created (n = 10): Group 1, group with intrinsic pigmentation and without extrinsic pigmentation (control) and Group 2, group with intrinsic and extrinsic pigmentation. Samples were submitted to color and Shore A hardness tests, before and after 1,008 hours of aging. Statistical Analysis Color alteration data were submitted to Student’s t-test (α = 0.05). Shore A hardness data were submitted to two-way analys...
This review presents a classification system for maxillofacial prostheses, while explaining its t... more This review presents a classification system for maxillofacial prostheses, while explaining its types. It also aims to describe their origin and development, currently available materials, and techniques, predicts the future requirements, and subsequently discusses its avenues for improvement as a restorative modality. A literature search of the PubMed/Medline database was performed. Articles that discussed the history, types, materials, fabrication techniques, clinical implications, and future expectations related to maxillofacial prostheses and reconstruction were included. Fifty-nine articles were included in this review. Maxillofacial prostheses were classified as restorative or complementary with subclassifications based on the prostheses finality. The origin of maxillofacial prostheses is unclear; however, fabrication techniques and materials have undergone several changes throughout history. Currently, silicones and acrylic resins are the most commonly used materials to fabri...
Objectives: The aim of this study was to evaluate the influence of different polymerization metho... more Objectives: The aim of this study was to evaluate the influence of different polymerization methods of acrylic resin for ocular prostheses on the subcutaneous tissue inflammatory response of rats. Methods: Samples were prepared by: water bath (WB), microwave energy (MW), or autopolymerization (AP) (n=20/group). The inflammatory response (cell count and immunohistochemical analysis of IL-1β, IL-6, TNF-α, IL-17, and MIP-3α) was analyzed by the implantation of a sample from each group in the subcutaneous tissue of 20 Wistar rats, and evaluated after 7, 15, 30, and 60 days. Quantitative and qualitative data were submitted to ANOVA and Tukey test (p<0.05) and to visual comparison, respectively. Results: There was a moderate inflammatory infiltrate for MW and AP groups and a light infiltrate for the WB group after 7 days. The inflammatory infiltrate and the immunolabeling of tested targets decreased gradually during the 60 days. The AP group had the highest immunolabeling of TNF-α (7 d...
Objectives The aim of this study was to verify during facial expressions (“happy,” “sad,” “fearfu... more Objectives The aim of this study was to verify during facial expressions (“happy,” “sad,” “fearful,” “angry,” “surprised,” and “disgusted”) if: (1) there would be difference in the electromyography (EMG) of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles on the normal side (NS) compared with the affected side (AS) (without the use of an ocular prosthesis) in individuals with unilateral absence of the eyeball, and (2) the rehabilitation with a new ocular prosthesis would affect the EMG of the muscles studied on the AS in these individuals. Materials and Methods Thirteen individuals, without temporomandibular disorder, with good health, with unilateral absence of the eyeball (the eye must have been removed by evisceration or enucleation), and users or nonusers of an ocular prosthesis were included. EMG of the occipitofrontalis, temporal, masseter, and sternocleidomastoid muscles was performed during rest and facial expressions (“happy,” “sad,” “fearful,” “an...
Objective To analyze the influence of three pigment incorporation methods on color change, dimens... more 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...
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