Different Poisson

1
(No Transcript)
2

• Different Poissons ratios
• Shear stress at interface-bonding problems

3

• Less stress concentration when placed centrally

4
Load-Transfer

• Affected by bonding characteristics at interface
• Frictional/adhesive characteristics
• Orientation of interface relative to loading
  direction
• Surface microstructure/texture

5

• True only when bonded surface is perpendicular to
  loading direction

6

• Bonded case, both compressive and shear at
  interface, shear gt compressive for small angles
• Press-fit, get a tensile hoop stress in bone to
  prevent expansion, and maintain
  equilibrium-abnormal loading

7

• Rigidity of stem affects
• Bone stresses (may cause resorption)
• Interface stresses (may cause loosening)
• Non-cemented stems tend to be canal filling and
  thicker---hence.(more stiff, more stress
  shielding)
• Bone stiffness-VERY IMPORTANT

8
(No Transcript)
9
SENIOR DESIGN??