In vitro fatigue behavior of restorative composites and glass ionomers.
OBJECTIVE
This in vitro study was conducted to investigate the fatigue behavior of several dental restoratives, including composites, glass ionomers and a resin-reinforced glass ionomer.


METHODS
Fatigue was imposed under a reverse stress-controlled regimen, following a staircase approach. Samples were stored and tested under both dry and wet conditions. The following parameters were measured and analyzed: Young's modulus, restrained fracture strength, and flexural fatigue limit.


RESULTS
As a general trend, all products showed a decrease in Young's modulus following water sorption. For all products except the resin-reinforced glass ionomer, the same trend was seen in the restrained fracture strength. This is, however, no longer valid for the flexural fatigue limit: the trend is steady-state for the glass ionomers, status quo for the resin-reinforced glass ionomer, and all composites tested show a decrease.


CONCLUSIONS
The diversity in structure of both composites and glass ionomers does not allow findings for one product to be extrapolated to other similar products.
Braem
M J
MJ
University of Antwerp - RUCA, Dental Propedeutics, Antwerp, Belgium.
Lambrechts
P
P
Gladys
S
S
Vanherle
G
G
D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D020770:Compomers; D003188:Composite Resins / Q000737:chemistry*; D003799:Dental Stress Analysis; D004548:Elasticity; D005899:Glass Ionomer Cements / Q000737:chemistry*; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D018583:Pliability; D019279:Resin Cements; D012117:Resins, Synthetic / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014867:Water / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
C084111:Charisma composite resin; D020770:Compomers; D003188:Composite Resins; C088486:Dyract; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D008689:Methacrylates; D019279:Resin Cements; D012117:Resins, Synthetic; D017640:Silicates; C084550:Vitremer; C083568:Z100 composite resin; D014867:Water; C065770:Herculite XR; C065771:P50 composite resin; C074741:Silux Plus; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; D015040:Zirconium