Biomedical Engineering - Essay Example

Before the body part is replaced, compatibility of the biomaterial and the living tissue is of great consideration (Ratner 2004). Biocompatibility is the acceptance of the synthetic biomaterial by the immediate and surrounding tissues and by the body generally (Paul & Kelvin 2009). Appropriate host response is shown by lack of blood clotting, normal heating and resistance to bacterial colonization. It is essential therefore to study the biomaterial composition and also the way in which they react with the environment in which they are put which is the surrounding tissue (Pruitt 2011).

Hence, biomaterial selection involves the logical sequence of analysis of the problem, consideration of the requirement and consideration of the biomaterial properties. Biomaterials that match the properties of the bone and teeth These biomaterials have their physical characteristics that are needed to match the properties of the teeth or bone being replaced with (Ratner 2004). The mechanical properties of these biomaterials involve tensile testing that provides data on the characterization of the biomaterial. . Good heat conductors hence have high conductivity.

Coefficient of thermal expansion or thermal expansion coefficient It is by definition the fractional increase in length of a body for each degree (in centigrade) rise in temperature. ?=?L/Lo oC-1 ?T Where ?L is the change in length Lo is the original length of the biomaterial ?T is the change in temperature The values of ? are very small like for amalgam biomaterial, the value of ?=0.0000025 oC-1P.P.M Table showing the thermal conductivity coefficient of different biomaterials in parts per million (P.P.M) The original length of the tooth and the length attained when there is temperature change are calculated in order to determine the length of the biomaterial to be used in teeth filling.

Expensile structures ensure that the biomaterial conforms to the irregular bony defects (Paul & Kelvin 2009). This also helps prevent the undesired movement of the fibroblast into the graft site and these yields in optimizing the quality of the replaced bones. Coefficient of thermal expansion is widely considered in filling materials such as for the teeth with cavities. The above table shows different thermal conductivity values of different conductors used as biomaterials. Thermal diffusivity (D) Thermal diffusivity is defined by the equation; D=K Cp?

Where, K is the thermal conductivity Cp is the heat capacity ? is the density A low value of thermal diffusivity is preferred however there are occasions when the high diffusivity level are preferred to the low ones like if the base material to be used is denture. It is necessary since it retains a good response to both cold and hot stimuli in the mouth (Ratner 2004). Physical properties Physical structures and stability of the