Deterioration of mechanical properties of composite resins.
The deterioration of the mechanical properties of composite resins was examined. The bending strength and the stress relaxation rate for sixteen experimental composite resins with different filler shapes, particle sizes and filler contents immersed in distilled water for 0-60 days were measured. The bending strength of all of the composites decreased with the increase of the immersion time in water. The composites with a high filler content (65 vol%) showed a greater decreasing ratio of bending strength than those with low filler content (40 vol%). The stress relaxation rate also increased with and increase of immersion time. The phenomena may be caused by the hydrolytic degradation of the silane coupling agent (gamma-MPTMS).
Arikawa
H
H
Department of Dental Materials Science, Kagoshima University Dental School, Japan.
Kuwahata
H
H
Seki
H
H
Kanie
T
T
Fujii
K
K
Inoue
K
K
D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D004339:Drug Compounding; D006868:Hydrolysis; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D012821:Silanes / Q000737:chemistry*; D013046:Specific Gravity; D013314:Stress, Mechanical; D013997:Time Factors; D014867:Water / Q000737:chemistry
D003188:Composite Resins; D008689:Methacrylates; D011109:Polymethacrylic Acids; D012821:Silanes; D014867:Water; C020946:triethylene glycol dimethacrylate; C017492:methacryloxypropyltrimethoxysilane; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate