Citric Acid in Endodontics: A Review

Naturally occurring in citrus fruits, citric acid is categorized as a weak organic acid, which may exist both as a monohydrate or in an anhydrous form. In biochemistry, this organic acid acts as an intermediate in an essential metabolic process in all aerobic organisms called the Krebs cycle. The literature on citric acid in the context of endodontics up to June 2020 was reviewed using PubMed and MEDLINE. This review aimed to address the antibacterial efficacy of citric acid on endodontic microbiota, its effectiveness on the smear layer, the effects of its toxicity on fracture resistance of dentin, as well as the effectiveness of this acid on the removal of intra-canal medicaments. This report also addressed citric acid-containing endodontic irrigants.