Analysis of the physical, mechanical and morphological properties of polyethylene terephthalate polymer in the manufacture of dentistry prosthetic components

Some polymers have intrinsic characteristics that make them potential materials for application in prosthetic components. To evaluate the physical, mechanical and morphological properties of polyethylene terephthalate (PET) and to compare them with polyethylene, before and after thermocycling (5-55 & DEG;C, for 10.000 cycles), for possible use in the manufacture of prosthetic components. For each material, specimens were obtained to determine the hardness, surface roughness and compressive strength analysis. Three specimens of each material were used for morphological analysis by scanning electron microscopy (SEM). Some statistically significant differences in surface roughness and on compressive strength were found among the different materials (P < 0.001). PET was more susceptible to thermocycling so that all the evaluated properties presented a significant alteration, while only the compressive strength of the polyethylene was altered (P = 0.033). The thermocycling altered the surface morphology of the materials. The FTIR did not indicate changes in vibration modes, macromolecular structural changes and significant changes in crystallinity. DSC analysis showed a 10% increase in PET crystallinity and a reduction for polyethylene. X-RAY analysis has shown that polyethylene has a more crystalline structure showing sharper peaks in curves, before and after thermocycling. PET has characteristics that are good as polyethylene even with the effect of thermocycling; therefore, it has been demonstrating good properties for the preparation of dental prosthetic components, added to its low cost and favorable biocompatibility for use in the oral cavity.