Young’s Modulus

Young’s Modulus

Write a short note on Young’s modulus.
Or
Write a brief note on the modulus of elasticity.
Or
Write a short note on the modulus of elasticity.
Answer:

It is also referred to as ‘elastic modulus’ or ‘Young’s modulus’.

• It represents the relative stiffness or rigidity of the material within the elastic range.
• Young’s modulus is the ratio of stress to strain. Since stress is proportional to strain, the stress-to-strain ratio would be constant.
  • Modulus of elasticity or Young’s modulus strain
  • E = Stress/Strain = s/e
• It therefore follows that the less the strain for a given stress, the greater will be the stiffness, for example, If a wire is difficult to bend, considerable stress must be placed before a notable strain or deformation results.
• Such a material would possess a comparatively high modulus of elasticity.
• The unit of Young’s modulus is psi (pounds per square inch).

Clinical Application of Young’s Modulus of Elasticity:

An example of a clinical situation can be given with an illustration of the impression materials.

• Impression material should have a low modulus of elasticity to enable it to be removed from the undercut areas in the mouth.
• But at the same time, the modulus should not be so low that the material cannot withstand tearing.
• In restorative materials, generally, the modulus has to be high, i.e. the materials have to be stiff enough to withstand the forces of mastication.
• A material with a lower modulus is used to restore class V lesions since the material has to possess better flexural strength to withstand the flexural stresses acting in the cervical area.