“Mechanical & Functional Design While Critical Are Not Central To Biocompatibility”
“Biomaterials”, are those materials that are used in biomedical devices. They are either natural or synthetic, i.e. metals, polymers, hydrogels, ceramics, glasses, so on. They are mainly made of multiple compounds that can interact and adopt a biological system of the human body environment.
If biomaterials are to be used in implant devices or medical devices, it should possess certain mechanical and functional properties according to their place to be used. Good dimensional tolerance, corrosion resistance, good fatigue resistance, comparable strength, high wear resistance, so no are certain properties of biomaterials.
Every biomaterial has its own mechanical properties suitable for different body parts replacement. Example-alumina, bioglass, hydroxyapatite, zriconial (ceramic biomaterial), cobalt-chromium alloy, titanium and titanium alloys, stainless steels(metal), Polyvinylchloride(PVC), Polyethylene(PE), Polypropylene(PP), Polytetrafluoroethylene(PTFE), Polymethylmethacrylate(PMMA), Trimethylcarbonate, TMC NAD- Lactide(Polymer), Medical-grade silicon(short term implantable and long term implantable), etc. They all have their own specific mechanical properties that make it suitable for specific medical devices. Some have high/low elastic properties, stress and strain bearing properties, some are highly porous and some are not, and some have high/low value of permeability as need of mechanical properties, biomaterials are selected and surfaces are controlled and characterized.
Mechanical properties are essential for durability and its functional use. But only having all mechanical properties and functional design, it cannot be used as material for medical implant devices. It can show an adverse effect on human health or the functioning of the body. To avoid, “Biocompatibility” of that materials should be determined. It is important to ensure that the device’s material will not cause an unwanted biological reaction and does not produce a toxic or immunological response when exposed to the body fluid and body chemistry. Surface properties (smoothness, roughness, (water-loving) hydrophilicity, (water repealing) hydrophobicity, surface chemistry) have a major role to make biomaterials to be more biocompatible. The biological response to any implanted biomaterials is highly dependent upon materials' surface properties.
Biocompatibility is the term to describe the appropriate biological requirement of a biomaterial or biomaterials used in medical devices and medical implants. The materials surface not only bio-inert but also interact with and even respond to the biological environment where materials are implanted. It is a key concept in the understanding host response to biomaterials. A common definition of biocompatibility is “the ability of materials to perform with appropriate host response in a specific application.” It is most important for developing implants devices and improving the performance of those medical implant devices.
As a minimum requirement, biomaterials shouldn’t induce any unwanted response, like toxic reactions in the tissue where the material is implanted. The human body reads the surface structure of biomaterials and responds. Human tissues adopt implanted devices if and only if the surface properties of materials are body’s environment friendly. Biocompatibility is contextual. For sample biomaterial may be compatible in bone but not in blood and vice-versa. Considering an example of pacemaker placement, the design should not result in adverse coagulation and should be good fatigue resistance to work continuously as mimicking natural organ(heart). The pacemaker should not further cause infection in the body. Furthermore, Materials used during joint replacement should have a high level of hardness with a very low coefficient of friction. This will allow the joint parts to move properly. Also, materials should be durable to last against wear and tear and they should not show any adverse effect.
Biocompatible of a device depends upon material location in the human body duration of exposure and combination of materials. Example-titanium and its alloy are used for joint replacement, silicone rubbers are used as artificial skin & breast implant, polymethylmethacrylate (PMMA) used as bone cement, aluminum oxides are used in hip implants, silver as pacemaker wire, carbon as heart valve coating, cellulose as drug delivery and so on. are some biocompatible materials used in different parts of the body having different mechanical and functional design.
As a concluding note, mechanical property and the functional property are the critical properties of biomaterial as it describes the shape and designs its elasticity, stress & strain, tension and compression, share, porosity, permeability as only knowing about mechanical and functional design. We cannot determine whether the material is capable of an implant or not. Biocompatibility is also one of the major properties to be determined. And biocompatibility of materials is determined by the surface properties of biomaterials. Hence it concludes that mechanical and functional design being critical is not central to biocompatibility.
Comments
Post a Comment