Results : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
Mercury porosimetery revealed comparable (F = 0.057, P < 0.92) average pore diameter (85 ± 24 μm) for all the prepared scaffolds. Smallest pore diameter was 34 ± 2 μm and the largest pore diameter was 720 ± 13 μm. After filling the pores with hydroxyapatite, there was a significant (F = 16.1, P < 0.01) reduction in total porosity percent from 83 to 44 wt.% indicating that the nano-particles filled almost half of the available pores. There was also a significant reduction in average pore diameter from 85 ± 24 to 46 ± 29 μm. Amount of measured porosity was directly related to the measured bulk density of the scaffold structure. Agglomerates of hydroxyapatite particles were observed filling the porous structure (Fig. 1a, b).
EDX analysis of the enriched scaffolds revealed that Ca/P ratio was 1.67 indicating the presence of pure hydroxyapatite in the enriched scaffolds. XRD pattern revealed the characteristic peaks specific for the hexagonal HA crystal phase represented by (211), (112), and (300) peaks. Peaks of tetragonal yttrium zirconium oxide were detected for all specimens.
Histomorphometric analysis revealed that hydroxyapatite-enriched scaffolds had significantly (F = 14, P < 0.02) higher amount of new bone formation (33% ± 14) compared to the controls (21% ± 11). Amount of new bone formation was calculated as a percent of the total pore volume measured on each image. New bone growth started by lining pore cavity and propagated to gradually fill the entire pore volume (Fig. 2a). Bone ingrowth proceeded from the periphery of the scaffold and propagated towards its center (Fig. 2b). The surface under the guided tissue membrane was filled with unmineralized connective tissue. Regional areas of entrapped hydroxyapatite were observed inside the pore cavity of the enriched scaffolds (Fig. 2b). Entrapped islands of hydroxyapatite were surrounded by mineralized tissue. Lower amount of mineralized bone was observed for uncoated scaffolds (Fig. 3a, b).
Radiographic examination revealed clear margins separating newly inserted scaffolds from surrounding bone defect (Fig. 4a). After completion of healing time, the margins between the scaffold and bone defect became less demarcated due to deposition and ingrowth of new bone (Fig. 4b).
Serial posts:
- Background : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [1]
- Background : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [2]
- Methods : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [1]
- Methods : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [2]
- Methods : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [3]
- Results : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- Discussion : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [1]
- Discussion : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [2]
- Conclusions : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- References : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [1]
- References : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles [2]
- Acknowledgements : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- Author information : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- Rights and permissions : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- About this article : Osteogenesis ability of CAD/CAM porous zirconia scaffolds enriched with nano-hydroxyapatite particles
- Fig. 1. a SEM image, ×10,000, demonstrating internal porosity of the fabricated zirconia scaffolds. b SEM image, ×30,500, demonstrating agglomeration of nano-hydroxyapatite particles filling the porous structure : Osteogenesis ability of CAD/CAM porous zirconia sc
- Fig. 2. a Histological section demonstrating new bone growth (white arrow) in HA-enriched zirconia scaffold (black arrow). Unmineralized bone stained blue. Almost entire surface porosity was filled with new dense bone. b Histological section demonstrating bone growth in HA-enriched zirconia scaffold starting from the periphery of the surgical wound (white arrow). Islands of entrapped HA particles were surrounded by mineralized boney matrix (black arrow) which were identified using EDX : Osteogenesis ability of CAD/CAM porous zirconia sc
- Fig. 3. a Histological section demonstrating bone growth in control zirconia scaffold (white arrow). Mineralized bone formation (black arrow) was less dense compared to HA-enriched scaffolds. b Histological section showing different sizes of pores present in porous zirconia scaffolds (Control specimen). Mineralization started by lining pore walls (white arrow). Unmineralized bone stained blue : Osteogenesis ability of CAD/CAM porous zirconia sc
- Fig. 4. a Peri-apical X-ray of zirconia scaffold immediately placed in bone defect. Margins between scaffold and bone are clearly demarcated. b Peri-apical X-ray of zirconia scaffold after completion of healing time. Margins between bone defect and scaffold are less demarcated due to new bone growth : Osteogenesis ability of CAD/CAM porous zirconia sc