276
12 Collagen
It also reduces the period over which the patient has to withstand the pain and discomfort from the wound hence improvement in the quality of health care (Hochstein
and Bhatia 2014).
For effective wound healing the form in which the collagen is applied to the
wound is also important. The physical environment should be one which provides
the right architecture that promotes the forming of new skin cells. Collagen wound
healing materials have been made in the form of sponges produced using collagen
obtained from scales of mrigal fish (Pal et al. 2016), dressings made from electrospun
fibers of collagen extracted from tilapia fish (Moura et al. 2014; Zhou et al. 2016).
When tested in rat models, these different forms of collagen-based wound healing
materials showed enhancement of wound healing processes such as proliferation of
keratinocytes, fibroblast migration and collagen deposition.
12.7.3 Bone Regeneration
Collagen forms the matrix within which the bone mineral, hydroxylapatite is dispersed. Damage to the bone often requires a membrane to hold the bone in place
during healing after which the material is removed. The membrane serves to guide
the direction of bone regrowth ensuring that the bone returns to its original shape
and form. The removal of the membrane often requires an additional surgical procedure which implies more healthcare cost and further discomfort for the patient.
Non-biodegradable bone guiding membranes are made of materials such as polytetrafluoroethylene (Fiorellini et al. 1998), and this has the right mechanical properties
to support the bone regeneration and is unreactive enough not to induce an undesirable immune response by the body. It will also not be degraded by the matrix
metalloproteinase enzymes (MMPs) which are responsible for bone protein degradation, these enzymes get rid of damaged old bone tissue and replace with the newly
regenerated tissue (Armstrong and Jude 2002). In collagen-based scaffolds used in
bone regeneration, the activity of these MMPs enzymes is inhibited by treating the
scaffold with a tetracycline which inhibits the activity of MMPs (Moses et al. 2008).
Scaffolds are used where starter cells as well as a structural guide are required to
aid tissue regeneration. Collagen-based scaffolds have been developed with the goal
to replicate the macro- and microstructure of the bone tissue. Using collagen and
hydroxyapatite composites for such scaffolds further better mimics the biological
tissue physically and chemically. Different forms of these collagen/hydroxyapatite
scaffolds have been presented for bone regeneration applications (Zhang et al. 2018;
Xia et al. 2013; Yunoki et al. 2006, 2007). However, there is limited understanding of the complex mineralization process and reproducing the intricately ordered
nanocrystalline structure of the collagen/mineral bone composite is not yet achievable. Further, development is still required in the area of tissue engineering to develop
tissue scaffolds which better mimic the tissue structure.
The area of bone regeneration has further advanced toward development of 3D
printed scaffolds (Govindharaj et al. 2019). The ability to 3D print tissue scaffolds
12 Collagen
It also reduces the period over which the patient has to withstand the pain and discomfort from the wound hence improvement in the quality of health care (Hochstein
and Bhatia 2014).
For effective wound healing the form in which the collagen is applied to the
wound is also important. The physical environment should be one which provides
the right architecture that promotes the forming of new skin cells. Collagen wound
healing materials have been made in the form of sponges produced using collagen
obtained from scales of mrigal fish (Pal et al. 2016), dressings made from electrospun
fibers of collagen extracted from tilapia fish (Moura et al. 2014; Zhou et al. 2016).
When tested in rat models, these different forms of collagen-based wound healing
materials showed enhancement of wound healing processes such as proliferation of
keratinocytes, fibroblast migration and collagen deposition.
12.7.3 Bone Regeneration
Collagen forms the matrix within which the bone mineral, hydroxylapatite is dispersed. Damage to the bone often requires a membrane to hold the bone in place
during healing after which the material is removed. The membrane serves to guide
the direction of bone regrowth ensuring that the bone returns to its original shape
and form. The removal of the membrane often requires an additional surgical procedure which implies more healthcare cost and further discomfort for the patient.
Non-biodegradable bone guiding membranes are made of materials such as polytetrafluoroethylene (Fiorellini et al. 1998), and this has the right mechanical properties
to support the bone regeneration and is unreactive enough not to induce an undesirable immune response by the body. It will also not be degraded by the matrix
metalloproteinase enzymes (MMPs) which are responsible for bone protein degradation, these enzymes get rid of damaged old bone tissue and replace with the newly
regenerated tissue (Armstrong and Jude 2002). In collagen-based scaffolds used in
bone regeneration, the activity of these MMPs enzymes is inhibited by treating the
scaffold with a tetracycline which inhibits the activity of MMPs (Moses et al. 2008).
Scaffolds are used where starter cells as well as a structural guide are required to
aid tissue regeneration. Collagen-based scaffolds have been developed with the goal
to replicate the macro- and microstructure of the bone tissue. Using collagen and
hydroxyapatite composites for such scaffolds further better mimics the biological
tissue physically and chemically. Different forms of these collagen/hydroxyapatite
scaffolds have been presented for bone regeneration applications (Zhang et al. 2018;
Xia et al. 2013; Yunoki et al. 2006, 2007). However, there is limited understanding of the complex mineralization process and reproducing the intricately ordered
nanocrystalline structure of the collagen/mineral bone composite is not yet achievable. Further, development is still required in the area of tissue engineering to develop
tissue scaffolds which better mimic the tissue structure.
The area of bone regeneration has further advanced toward development of 3D
printed scaffolds (Govindharaj et al. 2019). The ability to 3D print tissue scaffolds