The effects of cyclic stress on dental polymethylmethacrylate. I. Thermal and environmental fluctuation.

Alternative resins to traditional denture base acrylic need to be assessed for both short- and long-term performance before their potential can be evaluated. Much dental materials testing is carried out on fresh material and a baseline of knowledge about the properties of aged material is incomplete. Studies have been carried out to examine the effects of thermal and environmental fluctuation on dental acrylic, with testing procedures reconsidered so as to resemble service conditions as closely as possible. Thermal cycling proved detrimental to the resin only when superimposed on intermittent partial drying out and resaturation.