Dimensional stability of acrylic denture base material after poly vinyl pyrrolidone addition

Abstract

Problem Denture base dimensional changes were found with commercial theremocured acrylic resins. The dimensional stability of acrylic resin denture base is the main necessity effects the retention and stability of the denture. This study was conducted to measure the dimensional accuracy of experimental prepared material in comparison with control material before and after thermo cycling cured by water bath and microwave. In this stady the total (40) specimens of heat cure acrylic resin lower denture base were cured by water bath and microwave after addition poly vinyl pyrrolidone (PVP). (Experimental). Preparation of modified heat cured denture base acrylic resin was carried out by preparing of (PMMA) (80%) and poly vinyl pyrrolidone (PVP) (20%) and the liquid part composed of methyl methacrylate (MMA) monomer. Evaluation was made by measuring dimensional stability and accuracy. Distances were measured between (3) points marked on denture bases "AB, AC and BC" before and after thermo cycling for both control and experimental groups. The result of this study showed that there was no significant differences (p>0.05) between control and experimental groups at three point "AB, AC and BC" before and after thremocycling. Dimensional stability and accuracy was not influenced by addition of PVP to acrylic denture base resin before and after thermo cycling in both heat and microwave treatment.