C

Tetracycline, citric acid and EDTA are well-documented root-conditioning agents used to remove the smear layer and expose collagen on dentin surfaces before or after placing materials such as MTA [Minocha et al., 2012, PMID 23162325]. Polyacrylic acid, on the other hand, is employed mainly as a dentin conditioner to improve bonding of glass-ionomer cements, not for root surface conditioning [Tyas, 1994, PMID 7945049].