Anti microbial activity of dimercaptosuccinic acid (DMSA): a new chelating agent.

Successful outcome of endodontic treatment depends on elimination of bacteria and their products present in the root canal. It has been reported that after careful chemicomechanical preparation, smear layer is formed on the walls of canal, which contains bacteria and their products. Chelating agents, when used during chemicomechanical preparation, remove the smear layer. DMSA--a new chelating agent, when used in root canals, removes the smear layer more than EDTA when used as irrigant in root canals. This study was conducted to determine whether DMSA has anti microbial activity and compare it with EDTA. The results show that EDTA (10% & 15%) had marked anti microbial activity, both on culture plates and in broth. DMSA (10% & 15%) did not show anti microbial activity on culture plates while in broth it had marked activity.