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On the development of life prediction methodologies for the failure of human teeth

Description: Human dentin is known to be susceptible to failure under cyclic loading. Surprisingly, there are few reports that quantify the effect of such loading, considering the fact that a typical tooth experiences a million or so loading cycles annually. In the present study, a systematic investigation is described of the effects of prolonged cyclic loading on human dentin in a simulated physiological environment. In vitro stress-life (S/N) data are discussed in the context of possible mechanisms of fatigue damage and failure.
Date: September 18, 2002
Creator: Nalla, R.K.; Imbeni, V.; Kinney, J.H.; Marshall, S.J. & Ritchie, R.O.
Partner: UNT Libraries Government Documents Department

On the in vitro fracture toughness of human dentin

Description: The in vitro fracture toughness of human dention has been reported to be of the order of 3 MPa sqrt m. This result, however is based on a single study for a single orientation, and furthermore involves notched, rather than fatigue precracked, test samples.
Date: February 5, 2002
Creator: Imbeni, V.; Nalla, R.K.; Bosi, C.; Kinney, J.H. & Ritchie, R.O.
Partner: UNT Libraries Government Documents Department

On the mechanistic role of the dentin-enamel junction in preventing the fracture of human teeth

Description: The dentin-enamel junction (DEJ), which is the interface between the dentin and outer enamel coating in teeth, is known for its unique biomechanical properties that provide a crack-arrest barrier for flaws formed in the brittle enamel. In this work, we re-examine how cracks propagate in the proximity of the DEJ, and specifically quantify, using interfacial fracture mechanics, the fracture toughness of the DEJ region. Additionally, we show that the vital function of the DEJ, in preventing cracks formed in enamel from traversing the interface and causing catastrophic tooth fractures, is not necessarily associated with the crack-arrest capabilities of the DEJ itself, but rather with the development of crack-tip shielding, primarily from uncracked-ligament bridging, in the mantle dentin adjacent to the DEJ. Measurements of the toughness of the DEJ region give estimates of G{sub c} {approx} 115 J/m{sup 2}, i.e., {approx}5 to 10 times higher than enamel and {approx}75 percent of that of dentin.
Date: September 1, 2004
Creator: Imbeni, V.; Kruzic, J.J.; Marshall, G.W.; Marshall, S.J. & Ritchie, R.O.
Partner: UNT Libraries Government Documents Department