Authors: Vander Wall GL, Dowson J, Shipman C Jr.
Title: Antibacterial efficacy and cytotoxicity of three endodontic drugs.
Journal: Oral Surg Oral Med Oral Pathol
Date: Feb 1972
Citation: 32(2):230-241
Category: Irrigants and Medicaments
Evidence-based Ranking: 5
Purpose/Objectives: To determine whether clinical doses of the drugs are effective inhibitors of bacterial growth and to measure the toxicity of these drugs in a mammalian cell culture system. The drugs tested were formocresol (FC), camphorated parachlorophenol (CMP), and Cresatin (C).

Materials & Methods: 3 antibacterial studies were done concurrently. Study A tested the drugs for their antibacterial effectiveness against 3 microorganisms while in direct contact with them, study B tested the antibacterial effectiveness of the drugs when kept 4-6mm from the bacteria, and study C evaluated the drugs effectiveness through the tooth. 2 cytotoxicity studies were performed on human embryonic lung cells. Study A tested the drugs in direct contact with the cells, while study B was set up similarly to study C.

Results: Antibacterial study A – all three drugs produced some inhibition, FC was the most effective, C the least. The more FC used, the larger the inhibition. Study B – FC was the only drug to produce a zone of inhibition when not in direct contact. Study C – FC was the only drug which inhibited bacterial growth around the apices of the teeth. In the cytotoxicity study A – all three drugs produced cell death when in direct contact with the cells, and study B – C produced no zones of cell death in any experiments, CMP produced minimal zones of cell death, and FC produced more zones than CMP.

Author’s Conclusion: FC was the most effective antibacterial drug, and the only effective drugs when not used in direct contact with the bacteria. Although FC was the most toxic, clinical doses confined to the pulp chamber were relatively nontoxic to mammalian cells. CMP was effective only when in conctact, and it’s toxicity behaved similarly, though lesser than FC. Cresatin was not effective, nor toxic.

Validity of Conclusion: The results are valid.

Reviewer’s Comments: The paper supports the use of FC from an antibacterial standpoint, although ongoing research continues to evaluate FC’s potential toxicity and mutagenic potential.