Evaluation of the mechanical behavior of odontological models in polyurethane resin
Abstract
The aim of the present study was to evaluate the mechanical behavior of a polyurethane resin Quartz-die (Zermack - Italy) used for dental modeling. The mechanical properties of the aforementioned material were compared to a type IV plaster Durone (Dentsply - Brazil). A metallic matrix was molded using condensation silicon Speedex (Coltène - Switzerland) and produced specimens of 12mm in height and 6mm in diameter. Eight specimens of each material were submitted to compression assays using the Universal EMIC DL 2000 machine with a load of 2000Kgf and at a speed of 0.05mm/min. The hexagonal specimens were also evaluated using the Sussen Wolpert type Testor HTl Durometer using a 12.7mm spherical penetrator, thus establishing values for Rockwell hardness. Data were analyzed using the non-parametric Kruskal- Wallis test with a significance level set at p<0.05. In accordance with the adopted parameters, it could be concluded that the polyurethane resin Quartz-die showed a lower compression resistance and a lower superficial hardness than did the Type IV plaster.
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References
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