The influence of hydrostatic pressure on tissue engineered bone development

• Novel model of the bone mineralisation response to an applied hydrostatic pressure.
• Three candidate constitutive forms of the pressure dependent response developed.
• A qualitative comparison to experimental observations is made.
• Qualitative agreement with experimental data for one response developed.
• Illustration of the importance of the cell “memory” and cell “recovery time”.

The hydrostatic pressure stimulation of an appropriately cell-seeded porous scaffold within a bioreactor is a promising method for engineering bone tissue external to the body. We propose a mathematical model, and employ a suite of candidate constitutive laws, to qualitatively describe the effect of applied hydrostatic pressure on the quantity of minerals deposited in such an experimental setup. By comparing data from numerical simulations with experimental observations under a number of stimulation protocols, we suggest that the response of bone cells to an applied pressure requires consideration of two components; (i) a component describing the cell memory of the applied stimulation, and (ii) a recovery component, capturing the time cells require to recover from high rates of mineralisation.