Advances in Human Biology (Jan 2014)
To Evaluate the Effect of Steel Strengtheners on Fracture Resistance of Heat Cured Methyl Methacrylic Resin - An in Vitro Study
Abstract
Aim : The acrylic resin material is an indispensable material in removable prosthodontics. There has been continuous search to reduce processing time and enhance physical properties such as strength deformation. Fracture of acrylic resin is an unresolved problem in removable prosthodontics. Numerous attempts have been made to determine its causes. The present study was done to compare the fracture resistance of acrylic resin denture base reinforced with steel strengtheners. Materials and Methods : To measure the fracture resistance of heat cure acrylic resin, a total of ,, specimens were prepared and divided into , categories: Group,: No strengtheners, Group ,: Thin gauge strengtheners and Group ,: Thick gauge (,., mm X , mm). All the samples prepared were of specific dimensions i.e. ,, mm in length, ,, mm in width and , mm in thickness as a means for standardization. The flexural strength of the samples was recorded using a universal testing machine and the data obtained was statistically analysed. The statistical analysis was done by calculating the average and standard deviation for each parameter used in the study. To find out the significant difference between different concentrations and different time intervals unpaired ′t′ test was performed. Here ′p′ and′t′ value is used to evaluate the fracture resistance. Results: Acrylic samples with steel strengtheners fared better when compared to those without steel strengtheners. Thick gauge strengtheners were found to be more resistant to fracture. The difference was statistically significant. Conclusion: The incorporation of thick steel strengtheners few millimetres apart and perpendicular to anticipated line of fracture will produce significant resistance to flexure and reduce the likelihood of fracture of the acrylic resin denture base.