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What is Citric acid concentration in MTAD is: and explain in detail?
Composition

Tetracycline:

– It is bacteriostatic, broad spectrum antibiotic.
– It has low pH and acts as calcium chelator.
– It removes smear layer.
– It has property of substantivity. 
– It promotes healing.

Citric acid (4.25%): It is bactericidal in nature and removes smear layer.
Detergent (Tween 80): It decreases surface tension.