An Investigation into the Fracture Behavior of a Particulate-filled bis-GMA Resin

Abstract

Dental composites are being increasingly used to restore occlusal surfaces ofposterior teeth. If these restorations are not to fracture in service, an understanding of their fracture behavior is essential. The fracture parameter used is the stress-intensity factor at crack instability (Kic). This has been calculated by means of the double-torsion test in a mechanical testing machine.The fracture behavior of the composite was studied by varying: the amount offiller (7%, 15%, 26%, and 41% by volume); the surface treatment of the filler (coated or uncoated); the environment (air and water); and the cross-head rate (0.05, 0.5, 5, and 50 mm/min).Fracture was found to occur in either a continuous (stable) or stickslip (unstable) manner. The stick-slip behavior was due to blunting of the crack tip, which was controlled by the yield behavior. When there was no significant blunting, continuous crack growth occurred. An unique relationship was found to exist between the yield stress and the stress-intensity factor for all conditions of testing.

Surface and bulk properties of dental resin- composites after solvent storage

“…Ethanol has been approved by the U.S food and drug administration (FDA,1976) as a clinically relevant food simulator [38]. MEK has been approved as a food additive by the FDA and it is naturally found in meat, yogurt, fruits and vegetables [38,39].…”

Zirconia nanoparticles prepared by laser vaporization as fillers for dental adhesives

“…The same occurs if the crack deviates from its original plane as it encounters a second phase structure. Local plastic deformation around the particle has also been demonstrated to increase the fracture toughness of epoxy- [27] and bis-GMA-based [28] composites.…”

Assessment of decontamination methods as pretreatment of silanization of composite glass fillers

“…Rather soon after their introduction in the 1960s, their application in posterior teeth was explored. [1][2][3] However, especially in medium-to-large stress-bearing areas, restorative composites should still today be applied with care because of their relatively weak wear and fatigue resistance. [4][5][6][7][8][9][10][11][12] The life expectancy of posterior composite restorations depends, among other factors, to a large extent upon the effects of occlusion and articulation: they generate wear, marginal breakdown, and cyclic loading.…”