Effect of tropical outdoor weathering on the surface roughness and mechanical properties of maxillofacial silicones
| Autor: | Minhaz Ul Islam Nizami, Mohammad Khursheed Alam, Adam Husein, Nafij Bin Jamayet, Yanti Johari, Ahmed Mushfiqur Rahman |
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| Rok vydání: | 2022 |
| Předmět: |
Dental Implants
Universal testing machine Materials science Maxillofacial Prosthesis Surface Properties Ultraviolet Rays Vulcanization Weathering 030206 dentistry law.invention 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Silicone chemistry law Materials Testing Ultimate tensile strength Silicone Elastomers Surface roughness Profilometer Oral Surgery Elongation Composite material Weather |
| Zdroj: | The Journal of Prosthetic Dentistry. 127:937-942 |
| ISSN: | 0022-3913 |
| Popis: | Statement of problem The climate of tropical Southeast Asia includes high humidity and ultraviolet radiation that reduce the lifespan of silicone prostheses by inducing changes in their mechanical properties and color stability. Studies on the surface roughness (SR) and mechanical properties of different silicone elastomers (SEs) subjected to the natural tropical weather of Southeast Asia are lacking. Purpose The purpose of this in vitro study was to evaluate the SR, tensile strength (TS), and percentage elongation (% E) of different SEs subjected to outdoor weathering in the Malaysian climate. Material and methods Type-II dumbbell-shaped specimens (N-120) (nonweathered=15, weathered=15) were made from 3 room-temperature vulcanized (A-2000, A-2006, and A-103) and 1 heat-temperature vulcanized (M-511) silicone (Factor II). For 6 months, weathered specimens were subjected to outdoor weathering inside a custom exposure rack. Simultaneously, the nonweathered specimens were kept in a dehumidifier. Subsequently, the SR was measured with a profilometer; TS and % E were measured by using a universal testing machine. Two-way ANOVA was used to compare the means of the tested properties of the nonweathered and weathered specimens, and pairwise comparison was carried out between the silicones (α=.05). Results After outdoor weathering, the SR, TS, and % E were adversely affected by weathering in the Malaysian environment. Among the silicone materials, A-2000 showed the least TS changes (2.51 MPa), while A-2006 demonstrated significant changes in percentage elongation after outdoor weathering (266.5%). M-511 exhibited the highest mean value (2.50 μm) for SR changes. In addition, A-103 SE showed statistically significant differences in most pairwise comparisons for all 3 dependent variables. Conclusions Based on the evaluation of mechanical properties, A-103 can be suggested as a suitable silicone for maxillofacial prostheses fabricated for tropical climates. However, A-2000 can be a suitable alternative, although significant changes to surface roughness were detected after outdoor weathering. |
| Databáze: | OpenAIRE |
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