Explain the difference between a biomaterial and biological

Explain the difference between a biomaterial and biological materials. Also explain why bone may be classified a composite material. What is the difference between trabecular and cortical bone structures?

Solution

           Biomaterial is any substances other than drug, which can be a combination of synthetic and natural material, that can be used in treatment or replacement of any tissue organ or function of the body. For example contact lens, prosthetic implants, stents, artifical heart valve etc

           Biological material are natural material which is already present inside a living organism. For example many protein, cellulose, collagen, cells, chitin etc.

       Materials or biological tissues such as wood, dentin and bone are regarded as composite natural materials Bone is regarded as a natural composite material, which appears as it is in nature, rather than the artificial or man made composites. Composite materials are made up of two components, a matrix and reinforcement, that work together to produce enhanced strength. Bone has the right mix of two very different components: a very hard inorganic material called hydroxylapatite and a tough, fibrous organic material called collagen (the protein of leather). The bone makes up about 70% of the dry weight of bone, while collagen makes up most of the remaining 30%. If bones were made up entirely of hydroxylapatite, they would shatter under a load much like brittle materials. If they were made entirely of collagen, they would be flexible or rubbery. Instead, they have a perfect balance of both. Bone is a complex but ordered composite material having the function of resistance to mechanical forces and fractures. Mechanical properties of bone depend on the arrangement of collagen fibers which condition the deposition of mineral crystals and influences bone strength. By all these statements we can safely say that bone can be considered as a composite material.

              Cortical bone also known as compact bone is dense in structure, whereas trabecular bone also known ascancellous bone or spongy bone, is 50 to 90 percent porous. Cortical bone is heavy and hard because it must support the human body. whereas trabecular bone is light.

               Trabecular bone is located not only at the end of joints but is also found on the inside of bones. Inside this bone that red bone marrow is found, where arteries and veins run, and where the production of blood\'s cellular components take place.

             Cortical bone is solid, with the only pores being the holes or canals through which nerves and blood vessels run. These canals are surrounded by cells called osteocytes, and form rings called osteons, which are like thick tubes that made up compact bones. Nearly 80 percent of bone in the human body is compact bone.