Peroxide bleaches: effect on tensile strength of composite resins.
Research concerning bleaching agents on the mechanical properties of composite resin restorative materials has produced conflicting reports. Representative brands of composite resin restorative materials were studied, including microfil, hybrid, and posterior types. The bleaching agents selected were 30% hydrogen peroxide and two commercial brands of 10% carbamide peroxide. Ten specimens of each material, prepared according to American National Standards Institute/American Dental Association specification No. 27 for diametral tensile testing, were stored in bleaching agents for 1 hour and 168 hours at 37 degrees C. An equal number of specimens stored in deionized water with identical conditions were designated controls. Qualitative examination of bleached specimens revealed a marked change in color, especially the microfilled composite resins. There was no significant difference in tensile strength between controls and exposed samples at either time except for the diminished strength of microfilled composite resins in 30% hydrogen peroxide for one week (p < 0.01).
Cullen
D R
DR
Division of Oral Diagnosis, Loyola University School of Dentistry, Maywood, Ill.
Nelson
J A
JA
Sandrik
J L
JL
D000077463:Carbamide Peroxide; D003116:Color; D003188:Composite Resins / Q000737:chemistry*; D004338:Drug Combinations; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry*; D008422:Materials Testing; D010545:Peroxides / Q000737:chemistry*; D013718:Tensile Strength; D014073:Tooth Bleaching / Q000379:methods; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry
D003188:Composite Resins; D004338:Drug Combinations; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea; D006861:Hydrogen Peroxide