[The effect of composition on the mechanical properties of composite resin]

The objective of this investigation was to determine whether the composition of composite resin affects the amount of residual monomers and the strength of resin. Six types of resin composition were designed and 30 composite resin specimens were made in glass mold of 6mm diameter and 3mm height. The residual monomer of each specimen was extracted by 10cc ethanol solution for 1, 2, and 3 days of experiment. UV/Vis spectrophotometer was used to estimate the amount of residual monomer of the specimen, and universal testing machine was used to test the diametral tensile strength of the composite resin. The results were as follow; 1. Composite resins of 1% benzoyl peroxide concentration released the higher level of residual monomers than the resin of 0.8% benzoyl peroxide concentration. 2. t-Butylaminoethylmethacrylate.HF of 17% concentration exhibited the greater level of residual monomer than the other resin monomers. 3. As the concentration of the trimethylolpropane trimethacrylate increased, the amount of Bis-GMA residual monomer increased. 4. Composite resin of 1% benzoyl peroxide concentration showed higher tensile strength than the resin of 0.8% benzoyl peroxide concentration. 5. As the concentration of trimethylolpropane trimethacrylate increased above 50%, the strength of the composite resin decreased.