Strain-induced optical changes in demineralized bone

Michael R. Hardisty, Daniel F. Kienle, Tonya L. Kuhl, Susan M Stover, David P Fyhrie

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Bone "stress-whitens," becoming visibly white during mechanical loading, immediately prior to failure. Stress-whitening is known to make materials tougher by dissipating mechanical energy. A greater understanding of stress-whitening, both an optical and mechanical phenomenon, may help explain age-related increases in fracture risk that occur without changes in bone mineralization. In this work, we directly measure the optical properties of demineralized bone as a function of deformation and immersing fluid (with different hydrogen-bonding potentials, water, and ethanol). The change in refractive index of demineralized bone was linear: with deformation and not applied force. Changes in refractive index were likely due to pushing low-refractive-index fluid out of specimens and secondarily due to changes in the refractive index of the collagenous phase. Results were consistent with stress-whitening of demineralized bone previously observed. In ethanol, the refractive index values were lower and less sensitive to deformation compared with deionized water, corroborating the sensitivity to fluid hydration. Differences in refractive index were consistent with structural changes in the collagenous phase such as densification that may also occur under mechanical loading. Understanding bone quality, particularly stress-whitening investigated here, may lead to new therapeutic targets and noninvasive methods to assess bone quality.

Original languageEnglish (US)
Article number035001
JournalJournal of Biomedical Optics
Volume19
Issue number3
DOIs
StatePublished - 2014

Fingerprint

bones
Bone
Refractive index
refractivity
Fluids
fluids
Ethanol
ethyl alcohol
pushing
Deionized water
densification
Densification
Hydration
water
hydration
Hydrogen bonds
Optical properties
optical properties
Water
sensitivity

Keywords

  • biomechanics
  • bone
  • collagen fibril
  • Hansen's hydrogen bonding potential
  • refractive index
  • stress whitening
  • surface force apparatus
  • tissues

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biomaterials
  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics

Cite this

Strain-induced optical changes in demineralized bone. / Hardisty, Michael R.; Kienle, Daniel F.; Kuhl, Tonya L.; Stover, Susan M; Fyhrie, David P.

In: Journal of Biomedical Optics, Vol. 19, No. 3, 035001, 2014.

Research output: Contribution to journalArticle

Hardisty, Michael R. ; Kienle, Daniel F. ; Kuhl, Tonya L. ; Stover, Susan M ; Fyhrie, David P. / Strain-induced optical changes in demineralized bone. In: Journal of Biomedical Optics. 2014 ; Vol. 19, No. 3.
@article{fab00cb7ba9847eeaecd4d5d8204cfea,
title = "Strain-induced optical changes in demineralized bone",
abstract = "Bone {"}stress-whitens,{"} becoming visibly white during mechanical loading, immediately prior to failure. Stress-whitening is known to make materials tougher by dissipating mechanical energy. A greater understanding of stress-whitening, both an optical and mechanical phenomenon, may help explain age-related increases in fracture risk that occur without changes in bone mineralization. In this work, we directly measure the optical properties of demineralized bone as a function of deformation and immersing fluid (with different hydrogen-bonding potentials, water, and ethanol). The change in refractive index of demineralized bone was linear: with deformation and not applied force. Changes in refractive index were likely due to pushing low-refractive-index fluid out of specimens and secondarily due to changes in the refractive index of the collagenous phase. Results were consistent with stress-whitening of demineralized bone previously observed. In ethanol, the refractive index values were lower and less sensitive to deformation compared with deionized water, corroborating the sensitivity to fluid hydration. Differences in refractive index were consistent with structural changes in the collagenous phase such as densification that may also occur under mechanical loading. Understanding bone quality, particularly stress-whitening investigated here, may lead to new therapeutic targets and noninvasive methods to assess bone quality.",
keywords = "biomechanics, bone, collagen fibril, Hansen's hydrogen bonding potential, refractive index, stress whitening, surface force apparatus, tissues",
author = "Hardisty, {Michael R.} and Kienle, {Daniel F.} and Kuhl, {Tonya L.} and Stover, {Susan M} and Fyhrie, {David P}",
year = "2014",
doi = "10.1117/1.JBO.19.3.035001",
language = "English (US)",
volume = "19",
journal = "Journal of Biomedical Optics",
issn = "1083-3668",
publisher = "SPIE",
number = "3",

}

TY - JOUR

T1 - Strain-induced optical changes in demineralized bone

AU - Hardisty, Michael R.

AU - Kienle, Daniel F.

AU - Kuhl, Tonya L.

AU - Stover, Susan M

AU - Fyhrie, David P

PY - 2014

Y1 - 2014

N2 - Bone "stress-whitens," becoming visibly white during mechanical loading, immediately prior to failure. Stress-whitening is known to make materials tougher by dissipating mechanical energy. A greater understanding of stress-whitening, both an optical and mechanical phenomenon, may help explain age-related increases in fracture risk that occur without changes in bone mineralization. In this work, we directly measure the optical properties of demineralized bone as a function of deformation and immersing fluid (with different hydrogen-bonding potentials, water, and ethanol). The change in refractive index of demineralized bone was linear: with deformation and not applied force. Changes in refractive index were likely due to pushing low-refractive-index fluid out of specimens and secondarily due to changes in the refractive index of the collagenous phase. Results were consistent with stress-whitening of demineralized bone previously observed. In ethanol, the refractive index values were lower and less sensitive to deformation compared with deionized water, corroborating the sensitivity to fluid hydration. Differences in refractive index were consistent with structural changes in the collagenous phase such as densification that may also occur under mechanical loading. Understanding bone quality, particularly stress-whitening investigated here, may lead to new therapeutic targets and noninvasive methods to assess bone quality.

AB - Bone "stress-whitens," becoming visibly white during mechanical loading, immediately prior to failure. Stress-whitening is known to make materials tougher by dissipating mechanical energy. A greater understanding of stress-whitening, both an optical and mechanical phenomenon, may help explain age-related increases in fracture risk that occur without changes in bone mineralization. In this work, we directly measure the optical properties of demineralized bone as a function of deformation and immersing fluid (with different hydrogen-bonding potentials, water, and ethanol). The change in refractive index of demineralized bone was linear: with deformation and not applied force. Changes in refractive index were likely due to pushing low-refractive-index fluid out of specimens and secondarily due to changes in the refractive index of the collagenous phase. Results were consistent with stress-whitening of demineralized bone previously observed. In ethanol, the refractive index values were lower and less sensitive to deformation compared with deionized water, corroborating the sensitivity to fluid hydration. Differences in refractive index were consistent with structural changes in the collagenous phase such as densification that may also occur under mechanical loading. Understanding bone quality, particularly stress-whitening investigated here, may lead to new therapeutic targets and noninvasive methods to assess bone quality.

KW - biomechanics

KW - bone

KW - collagen fibril

KW - Hansen's hydrogen bonding potential

KW - refractive index

KW - stress whitening

KW - surface force apparatus

KW - tissues

UR - http://www.scopus.com/inward/record.url?scp=84896331328&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84896331328&partnerID=8YFLogxK

U2 - 10.1117/1.JBO.19.3.035001

DO - 10.1117/1.JBO.19.3.035001

M3 - Article

VL - 19

JO - Journal of Biomedical Optics

JF - Journal of Biomedical Optics

SN - 1083-3668

IS - 3

M1 - 035001

ER -