On the fracture of human dentin: Is it stress- orstrain-controlled?
Despite substantial clinical interest in the fractureresistance of human dentin, there is little mechanistic information inarchival literature that can be usefully used to model such fracture. Infact, although the fracture event indent in, akin to other mineralizedtissues like bone, is widely believed to be locally strain-controlled,there has never been any scientific proof to support this belief. Thepresent study seeks to address this issue through the use of a novel setof in vitro experiments in Hanks' balanced salt solution involving adouble-notched bend test geometry, which is designed to discern whetherthe critical failure events involved in the onset of fracture are locallystress- or strain-controlled. Such experiments are further used tocharacterize the notion of "plasticity" in dentin and the interaction ofcracks with the salient microstructural features. It is observed thatfracture in dentin is indeed locally strain-controlled and that thepresence of dentinal tubules does not substantially affect this processof crack initiation and growth. The results presented are believed to becritical steps in the development ofa micromechanical model for thefracture of human dentin that takes into consideration the influence ofboth the microstructure and the local failure mode.
- Research Organization:
- Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of Basic EnergySciences; National Institutes of Health. National Institute of Dental andCraniofacial Research Grant P01DE09859
- DOE Contract Number:
- AC02-05CH11231
- OSTI ID:
- 890659
- Report Number(s):
- LBNL--51378; BnR: KC0201020
- Journal Information:
- Journal of Biomed Materials Research, Journal Name: Journal of Biomed Materials Research Journal Issue: 67A Vol. 67A
- Country of Publication:
- United States
- Language:
- English
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