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P. Madiwale et al.
The materials used in tissue engineering as scaffolds form a crucial part of tissue
engineering. The materials to be used depend on the need of the scaffold and the part
of the body in which the scaffold is to be deployed [7].
Scaffold is a three dimensional material which act as supporting structure for tissue
regeneration. An accurate scaffold should have microstructures to enhance cellular
attachment, proliferation and differentiation and proper surface chemistry. The scaffold should have mechanical strength and biodegradability without producing any
undesirable by products [8].
The scaffold thus is a structure which acts as a skeleton for the growth of seeded
cell to attach, proliferate and differentiate. The scaffold is also known as a carrier for
cells, growth factors or other bio-molecular signals.
Cells of which the tissue or organ is to be regenerated are expanded in culture and
seeded onto a scaffold that will slowly degrade and resorb, as the tissue structures
grow in vitro and/or in vivo. It is of utmost importance to develop a scaffold as
to imitate exact properties of the desired human tissue and thus make available
environment for macroscopic process of tissue formation.
The functions of scaffolds in vitro or in vivo are to allow cell attachment, proliferation and differentiation; deliver and retain cells and growth factors. Scaffolds
permit diffusion of cell nutrients and oxygen to the tissue. They provide appropriate
mechanical and biological environment for tissue regeneration in appropriate manner [9]. Overall, bio-scaffold can be stated as a structure used to substitute an organ
either permanently or temporarily to restore functionality.
4 History
To restore the functionality of damaged organ and thus improve the quality of living,
the tissues engineering or scaffold engineering was introduced [10]. In seventeenth
century the use of artificial implants with the Romans had started. Romans used legs
made out of wood to replace damaged legs/limbs and used it to restore the functionality. Until 1962 the developments in the area of artificial implants were very slow.
Charnley replaced the damaged joints using low friction arthoplasty along with polytetraflouroethylene (PTFE). The advancement in artificial implants is very significant
in last six decades. Orthopaedic implants designed artificially are done using range
of materials like metallic, ceramic or polymers. Due to corrosion resistance stainless
steel (surgical grade) was widely used in orthopaedics and dentistry applications. In
later development Co–Cr and Ti alloys are used due to their biocompatibility and
bio inertness. The metallic implants can be replaced by ceramic but ceramic has its
own limitations in its use. The biocompatibility of the material and immune rejection
by the host cell are two measure concerns in the development of artificial implants.
This forced researchers to engineer and find suitable material which can be used as
regenerative medicine in growth of damaged tissues or organs. In 1980 with use of
autologuous (use of grafts from same species) skin grafts the research in the field of
implantable material got a head start [11]. The field of tissue engineering thereafter
P. Madiwale et al.
The materials used in tissue engineering as scaffolds form a crucial part of tissue
engineering. The materials to be used depend on the need of the scaffold and the part
of the body in which the scaffold is to be deployed [7].
Scaffold is a three dimensional material which act as supporting structure for tissue
regeneration. An accurate scaffold should have microstructures to enhance cellular
attachment, proliferation and differentiation and proper surface chemistry. The scaffold should have mechanical strength and biodegradability without producing any
undesirable by products [8].
The scaffold thus is a structure which acts as a skeleton for the growth of seeded
cell to attach, proliferate and differentiate. The scaffold is also known as a carrier for
cells, growth factors or other bio-molecular signals.
Cells of which the tissue or organ is to be regenerated are expanded in culture and
seeded onto a scaffold that will slowly degrade and resorb, as the tissue structures
grow in vitro and/or in vivo. It is of utmost importance to develop a scaffold as
to imitate exact properties of the desired human tissue and thus make available
environment for macroscopic process of tissue formation.
The functions of scaffolds in vitro or in vivo are to allow cell attachment, proliferation and differentiation; deliver and retain cells and growth factors. Scaffolds
permit diffusion of cell nutrients and oxygen to the tissue. They provide appropriate
mechanical and biological environment for tissue regeneration in appropriate manner [9]. Overall, bio-scaffold can be stated as a structure used to substitute an organ
either permanently or temporarily to restore functionality.
4 History
To restore the functionality of damaged organ and thus improve the quality of living,
the tissues engineering or scaffold engineering was introduced [10]. In seventeenth
century the use of artificial implants with the Romans had started. Romans used legs
made out of wood to replace damaged legs/limbs and used it to restore the functionality. Until 1962 the developments in the area of artificial implants were very slow.
Charnley replaced the damaged joints using low friction arthoplasty along with polytetraflouroethylene (PTFE). The advancement in artificial implants is very significant
in last six decades. Orthopaedic implants designed artificially are done using range
of materials like metallic, ceramic or polymers. Due to corrosion resistance stainless
steel (surgical grade) was widely used in orthopaedics and dentistry applications. In
later development Co–Cr and Ti alloys are used due to their biocompatibility and
bio inertness. The metallic implants can be replaced by ceramic but ceramic has its
own limitations in its use. The biocompatibility of the material and immune rejection
by the host cell are two measure concerns in the development of artificial implants.
This forced researchers to engineer and find suitable material which can be used as
regenerative medicine in growth of damaged tissues or organs. In 1980 with use of
autologuous (use of grafts from same species) skin grafts the research in the field of
implantable material got a head start [11]. The field of tissue engineering thereafter