RESUMEN
Grapefruit extract, a natural non-toxic solution derived from the seeds and pulp of grapefruit, has been shown to have antibacterial action. It disrupts the bacterial cell membrane and liberates cytoplasmic contents suggesting its potential to be used as endodontic irrigant. The antibacterial effect of grapefruit extract against three common endodontic pathogenic microorganisms [E. faecalis, S. aureus, and C. albicans] has been investigated and compared to two common endodontic irrigants [NaOCl 5.25% and CHX 2%]. Self-made ethanolic extract [33% m/V] of commercially available grapefruit was prepared. Two in vitro antimicrobial sensitivity tests [standard dilution susceptibility test and agar assay] were used. Ninety samples were studied per test. They were divided into 3 groups [n=30] according to the irrigant solution. Every group was further subdivided into 3 subgroups [n=10] according to the type of bacteria tested. NaOCl 5.25% and CHX 2% proved to be effective at lower concentrations than grapefruit extract [p