Biomaterial Database

Fracture toughness of human dentin. 1986

O M El Mowafy, and D C Watts

Plane strain fracture toughness (KIC) was determined for coronal dentin using compact tension test-pieces obtained from recently extracted permanent lower molar teeth. Specimens were prepared and tested such that the moving crack front was aligned parallel to the tubule orientation. The fracture toughness (KIC) was temperature-invariant in the range 0-60 degrees C, and the mean value obtained was 3.08 MN.(m)-1.5 (SD: 0.33). The critical strain energy release rate (GIC) of dentin was also calculated utilizing modulus data and was found to increase slightly with temperature, possibly as a consequence of significant temperature-dependence of the modulus: GIC = 2.31 (T degree C) + 653.2 (J .m-2) The fracture toughness of dentin is midway in the range (0.23 - 6.56) observed for cortical bone and is a factor of two greater than that exhibited by most current restorative materials.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D003799	Dental Stress Analysis	The description and measurement of the various factors that produce physical stress upon dental restorations, prostheses, or appliances, materials associated with them, or the natural oral structures.	Analyses, Dental Stress,Analysis, Dental Stress,Stress Analyses, Dental,Stress Analysis, Dental,Dental Stress Analyses
D003804	Dentin	The hard portion of the tooth surrounding the pulp, covered by enamel on the crown and cementum on the root, which is harder and denser than bone but softer than enamel, and is thus readily abraded when left unprotected. (From Jablonski, Dictionary of Dentistry, 1992)	Dentine,Dentines,Dentins
D004548	Elasticity	Resistance and recovery from distortion of shape.
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013314	Stress, Mechanical	A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.	Mechanical Stress,Mechanical Stresses,Stresses, Mechanical
D013500	Surface Tension	The force acting on the surface of a liquid, tending to minimize the area of the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Interfacial Force,Interfacial Tension,Surface Tensions,Tension, Surface,Tensions, Surface
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures
D013718	Tensile Strength	The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)	Strength, Tensile,Strengths, Tensile,Tensile Strengths
D014082	Tooth Fractures	Break or rupture of a tooth or tooth root.	Fracture, Tooth,Fractures, Tooth,Tooth Fracture