Which of the following are synthetic substitutes for cancellous bone (AIIMS May 2009)
|A||Hydroxyapatite and tricalcium phosphate|
|B||Calcium sulphate and osteocalcin|
|C||Calcium hydroxide and potassium sulphate|
|D||Oyster calcium and magnesium phosphate|
Hydroxyapatite and tricalcium phosphate
a. Hydroxyapatite and tricalcium phosphate synthetic and naturally occuring materials are now useds as substitutes for cancellous bone grafts in certain circumstances.
b. These porous materials are invaded by blood vessels and osteogenic cells and are in theory eventually replaced by bone.
c. Their primary usefulness is in filling cancellous defects in areas where graft strength is not important