Current Research

Age-related effect of remodeling on the toughness of bone

Hypothesis: Age-dependent changes in the collagen matrix are related to changes in the bone remodeling process, and such changes weaken the collagen network, and consequently cause decreased bone toughness.

Aim 1     To determine age-related changes in the mechanical integrity of secondary osteons and interstitial bone.

Aim 2      To determine age-related changes in the collagen matrix in secondary osteons and interstitial bone.

Aim 3      To determine if age-related decreases in collagen integrity are correlated with decreased bone   toughness (as a tissue) in aging.

KENS-5 News story regarding this research.

In situ determination of bone quality using nanotechnology

Hypothesis: the capacity of bone tissues in dissipating post-yield energy till failure is reflected by the removal energy consumed during a scratch test.

Aim 1:    To develop a mechanistic model of scratch on bone that is capable of assessing the post-yield energy dissipation or toughness of the tissue at micro/nano length scales;

Aim 2:    To validate the scratch approach by comparing the scratch results with those obtained from micro mechanical tests of osteon and interstitial bone tissues.

Numerical simulation of microdamage progression in bone

Hypothesis: microdamage formation (microcrack or diffuse damage) in bone is dependent on the ultrastructural and material properties of collagen fibrils and mineral matrix in the tissue.

Aim 1:  To develop a probabilistic failure model of mineral-collagen fibril composite to predict the mechanisms of damage formation in bone (i.e., either microcrack or diffuse damage) as a function of ultrastructural and material properties of mineral and collagen constituents

Aim 2:  To verify the probabilistic failure model using bone samples from several mice models

PTH treatments vs. extracellular matrix formation

Hypothesis: Intermittent PTH increases the activity of hemichannels formed by connexin 43 (Cx43), which in turn promotes bone formation.


Aim 1:  Determine the Activity of Hemichannels and Quality of the Bone Formed With and Without Intermittent PTH Treatment.


Aim 2:  Determine the Effects of Dosage and Duration of Intermittent PTH Treatment on Hemichannel Activities and Quality of the Bone.

Water distribution in bone and its contribution to bone mechanical behavior

Hypothesis: The interactions of water with the collagen and mineral phases each have a unique influence on mechanical behavior.

Aim1       To determine forms of water distribution in bone using a low field NMR approach.

Aim 2      To determine correlations of the distinct forms of water molecules with the mechanical behavior of bone at multiple length scales (from nano to macro).

Aim 3      To determine age-related changes in water distribution in bone and  its effects on the quality of bone at multiple length scales (from nano to macro).