The effect of autoclave polymerization on the tensile strength of various denture Base materials

Abstract

Objectives: The aim of this in vitro study was to evaluate the effect of autoclave polymerization method on the tensile strength of the polymethylmethacrylate (PMMA) acrylic denture base resins.Materials and Methods: Total of 60 specimens were fabricated from four different denture base materials such as three heat polymerized denture resins Meliodent, Paladent, and QC-20 and one microwave polymerized resin Acron MC. Specimens were divided into control (heat and microwave polymerization), short (130 °C 10 min) and long (130 °C 20 min) autoclave polymerization groups according to polymerization techniques (n=5). The tensile strength tests were performed. Data were analyzed by ANOVA followed by the Duncan test (α=0.01).Results: In control group, Acron-MC showed the highest tensile strength value, QC-20, Paladent and Meliodent were followed. Autoclave polymerization 20 minutes Acron MC group was significantly different from the other acrylic resins for the control and autoclave polymerization 10 minutes groups (p<0.01). Autoclave polymerized acrylic resin specimens showed higher tensile strength values than the control groups (p<0.01). There was no significant difference between the increasing time of autoclave polymerization methods 10 minutes and 20 minutes (p>0.01).Conclusion: Within the limitations of the study, autoclave polymerization method may provide a stronger alternative to conventional polymerization methods. Autoclave polymerization method provides high temperature that the activation ratio of cross-linking agents (glycoldimethacrylate) can be increased.