ISSN:
0736-0266
Keywords:
Stem prosthesis loosening
;
Bone cement
;
Metal/cement interface
;
Precoating
;
Fracture mechanics
;
Life and Medical Sciences
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
To characterize the strength of the interface between stem-type metal implants and bone cements, a fracture mechanics parameter was used. This parameter, the critical strain energy release rate (Gc), was determined from “push-out” tests of cylindrical specimens. The specimens, formed using molds of bone, were maintained and tested at body temperature. The strength of interfaces formed with cancellous bone surrounding the cement mantle was significantly less than the strength of those formed in apposition to cortical bone. A marked degradation of strength was found with saline immersion for SS316LVM/cement interfaces formed with Zimmer regular, Simplex-P, and Zimmer LVC cements. After 60 days of immersion the interface Gc was only 10-20% of the value for bulk cement. Interfaces formed with thin-film polymethylmetharcrylate-precoated metals (SS316LVM, Co-Cr-Mo, and Ti-6A1-4V) yielded “dry” Gc values one order of magnitude greater than those measured with interfaces formed with uncoated metals. Moreover, the strength of precoated SS316LVM/cement interfaces formed with all three brands of cement did not change after saline immersion for 60 days.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jor.1100020201
Permalink
