Author : ABDUL-LATIF RASHID, AMAL
Effect of The Elevated Temperature on the Tensile Strength of Cold Cured Acrylic Denture Base in Comparison to Heat Cure Acrylic
journal of kerbala university,
Volume 7, Issue 1, Pages 126-133
Acrylic denture base materials were possessing adequate mechanical strength to with stand the load of mastication. The strength properties of cold cured is lower than that of the heat cured. Studies were done to increase the strength of cold acrylic resin. The purpose of this study was to evaluate the tensile strength of cold cured when polymerized by elevated temperature and compare to those polymerized by conventional methods also to compare it with heat cured acrylic polymerized by the same methods.
Sixty specimens, thirty from cold cured acrylic and thirty from heat cured acrylic were prepared, flasking and packing procedure were done according to manufacturer direction and divided according to polymerization as follow:20 specimens(10 from cold cured and 10from heat cured acrylic)were polymerized by ivomat curing device containing water under air pressure 30 Pascal for 15 minutes at37˚C. 20 specimens (10 from cold cured and 10from heat cured acrylic) were polymerized by microwave oven; the power level was set at 50% to get 500 watts output for 3 minute and 20 specimens (10 from cold cured and 10from heat cured acrylic)were polymerized by water bath (fast cycle).All specimens were tested for tensile strength.
Result showed that the cold cured acrylic have high value of tensile strength when processed by elevated temperature (by water bath and microwave) in comparison to those processed by conventional methods (Ivomate)with highly significant differences P<0.01, There was no significant differences P=0.11 between cold cured acrylic groups that polymerized by water bath and heat acrylic groups that polymerized by microwave. Heat cured acrylic that polymerized by water bath show the maximum value for tensile strength followed by heat cured acrylic that polymerized by microwave, then by cold cured acrylic groups that polymerized by water bath ,while the least group for the tensile strength recorded by heat cured acrylic that polymerized by Ivomate. Also show there was significant and highly significant differences between all groups (cold and heat cured acrylic) processed by three methods (Ivomate, water bath, microwave).