Evalutation of mechanical properties of a new polyurethane elastomer material and its adhesion to maxillofacial silicone elastomer

The maxillofacial prosthetic materials should have many mechanical and physical properties such as high tear and tensile strength, hardness similar to the tissues being replaced. Lining the facial prosthesis with polyurethane film, which has better mechanical and pyhsical properties, is recommended. However it is very difficult to have strong adhesion between polyurethane and facial silicone elastomer. The aim of this study is to evalutation of adhesion capability of a new polyurethane elastomers to silicone elastomers without using primer with T-peel strenght test and evalutation of mechanical properties of new polyurethane elastomer with using tensile and tear strength tests . For evaluating of adhesion capability of a new polyurethane elastomer to silicone elastomer, a total of 240 strip shape (7.5 x 0.5 x 0.6 cm3) test specimens have been prepared using different silicone (A-2000, A-2186, MDX4-4210/Silastic Type A), primer (A-335, A-330 G, A-304), and liner (polyurethane, new polyurethane elastomer) materials for T-peel strength test. Data were analyzed using three-way ANOVA and post-hoc with Tukey (? = 0.05). For evaluating of mechanical properties of liner materials (polyurethane and a new polyurethane elastomer) 30 specimens were prepared for tear test (n:15) and 30 specimens were prepared for tensile tests (n:15). Data were analyzed using T-test (? = 0.05). According to the three-way ANOVA results there were statistically significant differences (p < 0.0001) between different silicone, primer and liner groups. New polyurethane elastomer adhere to silicone elastomers without primers and polyurethane did not adhere to silicone elastomers without primers in all groups. According to the T-test analysis results there were no statistically significant differences for tear energy, tear and tensile strength for each materials. There were statistically significant differences (p < 0.0001) for percentage elongation and percentage of plastic deformation among the materials. For these reasons, new polyurethane elastomer may be preferred as an alternative lining material for maxillo-facial prosthesis