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Tissue Engineering: A New Era of
Regenerative Medicine
The lack of tissue and organs available for transplantation, as well as the pro¬blems associated with their transplantation such as donor site morbidity, immune rejection, and pathogen transfer, led to the emergence of the discipline of tis¬sue engineering. The ultimate goal of tissue engineering as a treatment concept is to replace and even recover the anatomic structures and functions of the damaged, injured, or missing tissue and organs .
Tissue engineering is an advanced stage of biomaterials science as well. The big improvement of tissue engineering from traditional biomateri¬als science is that tissue engineering is the combination of both artificial compo¬nents ( i.e. biomaterials) and biological components ( i.e. cells, tissues, and biomolecules) to create analogues of normal tissue and organs. In contrast, tra¬ditional biomaterial science uses only artificial constructs to replace part of the normal functions of tissue and organs, rather than their anatomical structures. Therefore, tissue engineering requires various components including:
- regenera¬tion-component cells.
- carriers or support scaffolds.
- growth factors.
-dy¬namic forces.
Tissue engineering as a discipline is very young and still in the early de-velopmental stage. As such, there are lots of unknown mechanisms left to be investigated in this field. For instance, before attempting to grow any fully functional normal tissue in vitro or ex vivo:
- the precise mechanisms of normal tissue formation must be well understood.
-the appropriate physical, mechanical, chemical, and biological cues in normal tissue formation are cur¬rently far from understood.
-So do the knowledge on the environmental cues in engineering the functional tissue.
Surprisingly, after only approximately four decades of growth, the field of tissue engineering is no longer limited to the ac¬ademic laboratory but is rapidly growing in industry as well. For example, tis¬sue-engineered skin is already available on market shelves in many countries in¬cluding the United States and the United Kingdom; tissue-engineered cartilage, temporary liver-assistance devices, and tissue-engineered pancreas are all in clinical trials. Up to now, investigators have attempted to grow bone, liver, arteries, bladder, pancreas, nerves, cartilage, heart valves, corneas, and various other soft tissues.
1-General Aspects of Biomaterials Used for Tissue Engineering:
Biomaterials are artificial materials utilized to repair, assist, or replace dama¬ged or missing tissue or organs. Like any other industrial material, biomaterials can be classified into four different categories: metals, ceramics, polymers, and composites. In order for any material to be considered a biomaterial, it must satisfy certain physical, mechanical, and chemical behavior requirements and also be biocompatible. For example, the material must be strong enough to bear physiological loads, be resistant to undesired degradation or corrosion, not be carcinogenic, immunogenic, antileukotactic, or mutagenic, and so on. Many factors, such as implant size, shape, material composition, surface wettability, roughness, and charge influence implant biocompatibility .
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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