MECHANICAL AND TRIBOLOGICAL PROPERTIES OF DENTURE BASE

The present work illustrates the researches carried out to develop the mechanical and tribological properties of the denture base made of polymethyl methacrylate (PMMA). Because the denture base is subjected to the attrition with food and teeth, electrostatic charge (ESC) is generated. Based on that, the electric field induced by ESC is dangerous to the health of human beings. Experiments investigated the mechanical properties such as compressive strength, hardness, toughness and yield modulus. In addition to that tribological properties like friction coefficient and wear are reviewed. Several attempts are discussed dealing with reducing ESC generated during attrition at dry and wet sliding conditions. It was revealed that filling the denture base made of PMMA by nanoparticles such as TiO2, Al2O3, CuO, Fe2O3, SiO2, ZnO, chitosan nanoparticle, hydroxyapatite, glass, carbon, HDPE fibers and Silane-SiO2 nanocomposite reduced fractures of denture base and developed the mechanical properties. Besides, filling PMMA by Lavandula angustifolia (true lavender) is suggested to reduce dental plaque and oral bacteria. Voltage generated as result of the friction of the denture base can be reduced by filling PMMA by silver nanoparticles or reinforcing by carbon fibers. In addition to that, annealed PMMA denture base improves the mechanical properties due to the enhancement of the crystallization.