# A Biomechanical Approach for Bone Regeneration Inside Scaffolds Embedded with BMP-2

## Abstract

Scaffold-based strategies for Bone Tissue Engineering have been seen as a solution to repair bone in situations of large defect size and disease. Nevertheless, the factors that conduct to an optimal scaffold performance haven’t been fully determined yet in spite of the intense research work on this field. This work presents the development of a computational model to analyse concurrently the process of degradation and the cell/tissue invasion in an artificial bone substitute embedded with BMP-2. The computational procedure comprises a degradation model which takes in account the hydrolysis process and its enhancement by autocatalysis and a mechano-regulated bone tissue regeneration model based on cell differentiation and growth theories including the effect of BMP-2. It assumes the domain of study to be only a representative volume element of a periodic scaffold constituted by several volume elements with periodic properties. The effective elastic and permeability properties are computed using an asymptotic homogenization method. Results show that the inclusion of BMP-2 in the scaffold leads to an increase on bone formation velocity. At the end of the process the quantity of bone is not significantly different with and without BMP-2, but an early bone formation contributes to a better mechanical stability of the bone substitute.

## Keywords

Bone scaffolds Biodegradation Bone regeneration BMP-2 Tissue Engineering## Notes

### Acknowledgements

Authors would like to tank to Fundação para a Ciência e Tecnologia (Portugal) for the support through project PTDC/BBB-BMC/5655/2014 and LAETA project UID/EMS/50022/2019.

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