Water sorption and solubility of denture base resins– An evaluation

Statement of problems : Water sorption and solubility are important properties of acrylic resins. Denture base acrylic resins have low solubility. This solubility results from the leaching out of un-reacted monomer and water soluble additives into the oral fluids. The solubility of denture base acrylic resins can cause oral soft tissue reactions. In addition, water absorbed into this material acts as a plasticizer and changes the mechanical properties such as hardness, transverse strength,fatigue limit as well as color and dimensional stability. Purpose:The aim of this study was to compare the water sorption and solubility of four different brands of heat cure denture base acrylic resins (Stellon, Acrylin-H, Trevalon and Trevalon-HI). Materials and Methods: An experimental in vitro design was adapted. Four groups were prepared according to different brands of acrylic resin: Group A- Acrylin “H”, Group B- Trevalon, Group C- DetreyStellon and Group D- Trevalon “HI”. An eight circular discs specimen (diameter 50±0.01mm and thickness 0.5±0.01mm) that is two for each group were prepared. Discs were finished on the edge and equally from the both the molded surfaces to fabricate the discs of specific dimensions. The tests were conducted mainly in accordance with the American Dental Association Specification no. 12 / ISO: 1567-1981 (ISO: 6887-1986) for denture base acrylic resin. Intergroup differences were assessed using student “t” test.