Bonding of synthetic resin teeth to microwave or heat activated denture base resin

Bonding between acrylic resin teeth and a denture base material was investigated after microwave and hot water-bath curing. The specimens were tested according to the methods of the International Organisation for Standardisation (ISO 3336-1977 Dentistry-Synthetic Resin Teeth) using a universal testing machine. Superior bonding was found after hot water-bath curing. The generation of more porosities during microwave curing is the most likely explanation for the bond failures in this group. This finding is of clinical importance as the choice of curing method could influence the risk of loosening of acrylic teeth from the denture. No statistically significant difference in the fracture load between the two types of curing was found, which was expected as the load at fracture is not only related to the binding forces but also to factors such as the contact area and the fracture type.