Comparison of denture acrylic resins cured by boiling water and microwave energy

Transverse strength, hardness, water sorption, loss of mass by leaching and porosity were measured in accordance with Australian Standards on acrylic denture base resins cured by boiling water and microwave energy. The level of residual monomer measured by extraction in acetone and the degree of cross‐linking by immersion in chloroform were also studied. Results indicated similar physical properties and identical microstructures in the resins cured by the two methods. Using a previously recommended microwave curing programme, porosity was observed in thick specimens with a cross‐section of 14 mm × 10 mm. However, the microwave programme can be optimized to prevent porosity without prolonging the curing time or sacrificing the physical properties of the resins by starting the curing process at low wattage.