In vitro sodium fluoride exposure decreases torsional and bending strengthand increases ductility of mouse femora

Citation
Mj. Silva et Sr. Ulrich, In vitro sodium fluoride exposure decreases torsional and bending strengthand increases ductility of mouse femora, J BIOMECHAN, 33(2), 2000, pp. 231-234
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
JOURNAL OF BIOMECHANICS
ISSN journal
0021-9290 → ACNP
Volume
33
Issue
2
Year of publication
2000
Pages
231 - 234
Database
ISI
SICI code
0021-9290(200002)33:2<231:IVSFED>2.0.ZU;2-T
Abstract
Fluoride exposure in vivo can reduce the material strength of bone, an effe ct that has been attributed to a change in mineral structure. An in vitro m odel of fluoride exposure offers the potential to study directly the effect s of fluoride on bone mineral. Previous investigators have reported that so aking bones in sodium fluoride in vitro reduces bone strength. However, lon g soaking times and the absence of physiological buffering ions from their treatment solutions may have caused mineral dissolution that contributed to the decrease in bone strength. Our objectives were to further characterize the effects of in vitro fluoride exposure on bone mechanical properties an d to determine if the changes reported in previous studies of bovine cortic al bone would be observed for whole rodent bones. We soaked 60 mouse femora in sodium fluoride solutions. with and without physiological buffering ion s, and evaluated their torsional and bending properties. Fluoride soaked bo nes had a 30-fold increase in fluoride content and a 23% increase in water content compared to controls. These changes were associated with average re ductions in ultimate load of 45%: reductions in rigidity of 70%, and increa ses in deformation to failure of 80%. The effect of fluoride was similar fo r bones treated in buffered and non-buffered solutions, and was observed in both torsion and bending. Our findings confirm those of previous studies a nd highlight the strong effect that in vitro fluoride exposure has on bone mechanical properties. The in vitro model of fluoride exposure offers a too l to further study the effects of ion substitution in bone. (C) 2000 Elsevi er Science Ltd. All rights reserved.