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Rapid Mix Preparation of Bioinspired Nanoscale Hydroxyapatite for Biomedical Applications
Published on: February 23, 2017
Carbonate substituted hydroxyapatite: resorption by osteoclasts modifies the osteoblastic response
Gavin Spence1, Nelesh Patel, Roger Brooks
1Orthopaedic Research Unit, University of Cambridge, United Kingdom. gmspence59@yahoo.co.uk
Journal of Biomedical Materials Research. Part A
|May 23, 2008
Summary
Carbonate substitution in hydroxyapatite (HA) enhances osteoclast resorption, indirectly improving osteoblast responses. This suggests carbonate substitution may improve bone healing by altering bioceramic surfaces.
Area of Science:
- Biomaterials Science
- Cell Biology
- Orthopedic Research
Background:
- Carbonate substitution in hydroxyapatite (HA) is known to improve osteoconduction, but the underlying mechanisms remain unclear.
- Osteoconduction is crucial for bone regeneration, influencing how bone cells interact with and grow on implantable materials.
Purpose of the Study:
- To investigate the mechanism by which carbonate substitution in hydroxyapatite (CHA) influences osteoblast responses.
- To determine if osteoclast activity on CHA surfaces affects subsequent osteoblast proliferation and collagen synthesis.
Main Methods:
- Dense HA and CHA discs were cultured with human CD14+ cells and osteoclast-inducing factors (M-CSF, sRANKL) for 21 days.
- Osteoclast resorption of the ceramic surfaces was allowed, and some surfaces retained the conditioned proteinaceous layer.
- Human osteoblasts (HOBs) were seeded onto resorbed and unresorbed surfaces to measure proliferation and collagen synthesis.
Main Results:
- Osteoblast proliferation was significantly increased on surfaces previously resorbed by osteoclasts, provided the conditioned layer was intact.
- Collagen synthesis by osteoblasts was also enhanced on resorbed surfaces compared to unresorbed surfaces.
- This enhancement was observed on both HA and CHA, but occurred at an earlier time point on CHA.
Conclusions:
- Osteoclasts can modify synthetic bioceramic surfaces, altering subsequent osteoblast behavior.
- Carbonate substitution in HA may enhance osteoconduction indirectly by promoting enhanced bioresorption and surface conditioning.
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