2. Materials and methods
2. 1. Preparation of methods
2. 2. Scaffolds characterization
2. 3. Osteoblasts isolation and culture
2. 4. In vitro osteoblasts culture studies
2. 5. In vivo implantation studies
2. 6. DNA analysis
2. 7. Alkaline phosphatase assay (ALP assay)
2. 8. Histological studies
2. 9. Statistical analysis
3. Results and discussion
1. This novel sintering method is composed of pressing the mixture PLA, CMP, and salt particles followed by heat treatment.
2. The scaffolds had a homogeneously interconnected porous structure without a skin layer, and they exhibited a narrower pore size distribution and higher mechanical strength in comparison with scaffolds by solvent casting.
3. The number of cells attached to and proliferated on the scaffolds at both in vitro and in vivo culture was in the order of:
PLA by novel sintering < PLA/CMP by solvent casting < PLA/CMP by novel sintering
4. The alkaline phosphatase activity of and calcium deposition in the scaffolds explanted from mice were enhanced significantly for the scaffolds by novel sintering compared to them by solvent casting.
5. Such a superior characteristic of the novel sintering method should have resulted from the fact that the CMP particles could contact directly with cells/tissues to stimulate the cell proliferation and osteogenic differentiation, while the CMP particles would be coated by polymers and hindered to interact with cells/tissues in the case of a solvent casting method.
6. As the new Pressand-Baking method does not use any solvents it offers another advantage to avoid problems associated with solvent residue.
Biomaterials 26 (2005) 6314–6322
A poly(lactic acid)/calcium metaphosphate composite for
bone tissue engineering