ISSN:
0003-276X
Schlagwort(e):
Life and Medical Sciences
;
Cell & Developmental Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Medizin
Notizen:
The shearing strength of single human osteons has been investigated using a microtesting machine equipped with a microwave micrometer. The results Were related to the degree of calcification and the orientation of collagen fiber bundles in successive lamellae of the osteons. The following conclusions were made: (1) Osteons having a marked longitudinal spiral course of fiber bundles in successive lamellae are least able to support shearing stress. This suggests that in the other types of osteon the compactness of bone is strengthened by the lamellae having marked transversal spiral course of the fiber bundles. (2)Ultimate shearing strength and modulus of elasticity of osteons increase as calcification proceeds. (3) The shearing strength of single osteons is markedly lower than the tensile and compressive strength for samples of the same type. (4) In osteons loaded along their axis the range of elastic deformation is barely more than 1% of the length of the sample. (5) With the technical procedure used in this investigation the shearing of osteons appears to be preferentially related to the lamellar structure. In osteons loaded excentrically the portions which have slipped out have a rather irregular shape and in many cases one or two fractures occur. (6) The resistance to shearing of the cementing substance at the boundaries of the osteon may be greater than the resistance of the osteon itself.
Zusätzliches Material:
10 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/ar.1091720304
