Nanoceramics: Synthesis, Characterizations and Applications
149
4.5 Tissue Engineering Applications
4.5.1 Scaffold
Bone tissue engineering involves usage of scaffolds in the oral cavity and craniofacial
region and aims to restore alveolar bone after periodontal disease, peri-implantitis,
and reconstructive surgery after trauma, after cancer, etc. Tissue engineering provides
a suitable biochemical and physicochemical environment in which the osteoblasts
can attach to the scaffolds providing mechanical support and also optimize cells
osteogenic functions. With nanoceramics increased osteoblast adhesion and proliferation were observed on the material surface. Enhancement in their long-term function is also observed when their grain size is less than 100 nm [103, 84]. A good
scaffold should be able to degrade in vivo at a specific rate combined with a controlled
absorption rate that facilitates the formation of new bone in the space provided by
the two processes. Nanoscale scaffold materials are preferred as they are porous,
biodegradable and provide mechanical support during the process of bone repair
[104]. Scaffolds for bone repair can be developed using ceramic, metal, polymer
and composite materials. Nanoporous bioceramics have high mechanical strength,
enhanced bioactivity and resorbability and hence are being used effectively in tissue
engineering. Nanohydroxyapatite is now being clinically used on commercial scale.
Biopolymers can be used along with HAp, bioactive glass, chitosan, etc., to modify
the scaffolds properties such as porosity and growth factor delivering ability to have
greater functionality [105]. Chitin, chitosan-based scaffolds, and those reinforced
with nanoceramics such as hydroxyapatite (HAp), silicon dioxide (SiO 2 ), titanium
oxide (TiO 2 ), etc., are being extensively used in bone tissue engineering applications
[106]. Mesoporous silica nanocomposite scaffold loaded with BMP-7; enhanced
differentiation of bone marrow-derived mesenchymal cells (BMSC) from osteocytes
and initiated osteogenesis [107]. Three-dimensional (3D) periodic TiO 2 bio-ceramic
scaffolds have finer feature size. The scaffold favoured cell growth and attachment for
mouse osteoblastic cell line MC3T3-E1 indicating good biocompatibility of the scaffold. HAp scaffold with microporous structure and high interconnectivity is modified to have nanosheet, nanorod, or micro-nano-hybrids structure on the surface.
The scaffold promotes cell adhesion, proliferation and osteogenic differentiation of
adipose derived stem cells (ASCs) [108]. Nanoceramics such as HAp, β-tricalcium
phosphate, and bioactive glass were combined with gelatin or chitosan to prepare
composite scaffold material. The resultant scaffolds exhibited increased compressive
strength, high bioactivity, osteoblast adhesion and proliferation and hence stimulated
new bone regeneration [109]. Highly porous 3-D scaffolds of the Ag-bioactive glass
system of type 58.6SiO 2 —24.9CaO—7.2P 2 O 5 —4.2Al 2 O 3 —1.5Na 2 O—1.5K 2 O—
2.1Ag 2 O was found to have antibacterial property. The scaffold showed formation
of Hap after 2 weeks of in vitro bioactivity study in SBF and had anti-methicillinresistant Staphylococcus aureus (MRSA) effect on both direct and indirect exposure
[110].
149
4.5 Tissue Engineering Applications
4.5.1 Scaffold
Bone tissue engineering involves usage of scaffolds in the oral cavity and craniofacial
region and aims to restore alveolar bone after periodontal disease, peri-implantitis,
and reconstructive surgery after trauma, after cancer, etc. Tissue engineering provides
a suitable biochemical and physicochemical environment in which the osteoblasts
can attach to the scaffolds providing mechanical support and also optimize cells
osteogenic functions. With nanoceramics increased osteoblast adhesion and proliferation were observed on the material surface. Enhancement in their long-term function is also observed when their grain size is less than 100 nm [103, 84]. A good
scaffold should be able to degrade in vivo at a specific rate combined with a controlled
absorption rate that facilitates the formation of new bone in the space provided by
the two processes. Nanoscale scaffold materials are preferred as they are porous,
biodegradable and provide mechanical support during the process of bone repair
[104]. Scaffolds for bone repair can be developed using ceramic, metal, polymer
and composite materials. Nanoporous bioceramics have high mechanical strength,
enhanced bioactivity and resorbability and hence are being used effectively in tissue
engineering. Nanohydroxyapatite is now being clinically used on commercial scale.
Biopolymers can be used along with HAp, bioactive glass, chitosan, etc., to modify
the scaffolds properties such as porosity and growth factor delivering ability to have
greater functionality [105]. Chitin, chitosan-based scaffolds, and those reinforced
with nanoceramics such as hydroxyapatite (HAp), silicon dioxide (SiO 2 ), titanium
oxide (TiO 2 ), etc., are being extensively used in bone tissue engineering applications
[106]. Mesoporous silica nanocomposite scaffold loaded with BMP-7; enhanced
differentiation of bone marrow-derived mesenchymal cells (BMSC) from osteocytes
and initiated osteogenesis [107]. Three-dimensional (3D) periodic TiO 2 bio-ceramic
scaffolds have finer feature size. The scaffold favoured cell growth and attachment for
mouse osteoblastic cell line MC3T3-E1 indicating good biocompatibility of the scaffold. HAp scaffold with microporous structure and high interconnectivity is modified to have nanosheet, nanorod, or micro-nano-hybrids structure on the surface.
The scaffold promotes cell adhesion, proliferation and osteogenic differentiation of
adipose derived stem cells (ASCs) [108]. Nanoceramics such as HAp, β-tricalcium
phosphate, and bioactive glass were combined with gelatin or chitosan to prepare
composite scaffold material. The resultant scaffolds exhibited increased compressive
strength, high bioactivity, osteoblast adhesion and proliferation and hence stimulated
new bone regeneration [109]. Highly porous 3-D scaffolds of the Ag-bioactive glass
system of type 58.6SiO 2 —24.9CaO—7.2P 2 O 5 —4.2Al 2 O 3 —1.5Na 2 O—1.5K 2 O—
2.1Ag 2 O was found to have antibacterial property. The scaffold showed formation
of Hap after 2 weeks of in vitro bioactivity study in SBF and had anti-methicillinresistant Staphylococcus aureus (MRSA) effect on both direct and indirect exposure
[110].