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.
Downloads
References
Stolf DP, Zani IM, Soares CR, Volpato CAM, Stoeterau, RL. Textura da superfície de gessos especiais e reforçados. PCL Rev Ibero-am Prot Clin Laboratorial. 2004; 6:297-305.
Fan PL, Powers JM, Reid BC. Surface me- chanical properties of stone, resin and metal dies. J Am Dent Assoc. 1981; 103:408-11.
Anusavice KJ. Dental impression materials: reactor response. Adv Dent Res. 1988; 2:65-70.
Dias SC; Panzeri H. Comportamento tênsil de modelos odontológicos. 17ª. Reunião anual da sociedade brasileira de pesquisa odontológica
– SBPqO. 2000; Águas de Lindóia (SP), A- 114: 74.
Vilar WD. Química e tecnologia dos poliuretanos. 2ªed. Rio de Janeiro: Vilar Consultoria. 1999. p.11-7.
Conover WJ. Practical nonparametric statistics. New York: John Wiley & Sons. 1980.
Alsadi S, Combe EC, Cheng YS. Properties of gypsum with the addition of gum arabic and calcium hydroxide. J Prosthet Dent. 1996; 76:530-34.
Toreskog S, Phillips RW, Schnell RS. Properties of die materials: a comparative study. J Prosthet Dent. 1966; 16:119-31.
Ghahremannezhad HH, Mohamed SE, Stewart GP, Weinberg R. Effects of cyanocrylates on die stone. J Prosthet Dent. 1983; 49:639-46.
Skinner EW, Gordon CC. Some experiments on the surface hardness of dental stones. J Prosthet Dent. 1956; 6:94-100.
Cassimaty EM, Walton TR. Effect of three variables on the accuracy and variability of electroplated copper dies. Int J Prosthodont. 1996; 9:547-54.
Dias SC. O uso da resina epóxica carregada com zirconita para obtenção de modelos, a partir de moldes com elastômeros. [dissertação]. Ribeirão Preto: Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, 2000.
Vermilyea SG, Huget EF, Wiskoski J. Evaluation of resin die materials. J Prosthet Dent. 1979; 43:304-7.
Moser JB et al. Properties and characteristics of a resin die material. J Prosthet Dent. 1975; 34:297-313.
Dias SC. Resina epóxica carregada com diatomita para confecção de modelos odontológicos [tese]. Ribeirão Preto: Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, 2003.
Santos Júnior GC, Bastos LGC, Rubo JH. Avaliação das propriedades mecânicas do gesso tipo IV submetido a métodos de desinfecção: parte I - resistência à compressão e à tração diametral. Rev Fac Odontol Bauru. 2001; 9:87- 92.
Zaniquelli O. Formulação e caracterização de misturas de resina epóxica mais material de carga para uso como material para modelos. [dissertação]. Ribeirão Preto: Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, 1991.
Almeida, EES et al. Análise comparativa da alteração dimensional de materiais para obtenção de troquéis. PCL: Rev Bras Prót Clín Labor. 2002; 4:407-12.