Abstract
Polymer materials for denture bases, with thermal or light polymerization are relatively fragile, being considered brittle materials from the Fracture Mechanics concepts point of view. This paper presents a comparative study on determination of fracture toughness for 2 types of resins used in complete dentures technology: heat-curing resin (Meliodent), and light-curing resin (Eclipse). The tests were performed on a static loading machine, model Zwick/Roell of 5kN. The results obtained by 2 methods differ no more than 10-15%. Both methods showed that Eclipse has a better resistance to fracture than Meliodent. Keywords: acrylic resins, complete dentures, fracture toughness