RESUMO
The discovery of natural biocomponents from plants with antibacterial activity on endodontic microbiota may lead to new therapies. This study evaluated the antibacterial activity of a phytotherapeutic agent prepared from an ethyl acetate fraction (AcOEt) extracted from Arctium lappa. This agent was compared with calcium hydroxide as an intracanal dressing. Twenty-seven maxillary canines were instrumented, sterilized and inoculated with a mixed bacterial suspension of Pseudomonas aeruginosa, Escherichia coli, Lactobacillus acidophilus, Streptococcus mutans and Candida albicans. The teeth were divided into three groups and their canals filled with: group 1, calcium hydroxide and propylene glycol; group 2, a paste containing AcOEt fraction of A. lappa and propylene glycol; group 3, propylene glycol (control). At 7, 14 and 30 days, three teeth from each group were opened and a paper point was placed in the root canal for 5 min. The paper points were transferred to Petri dishes with Brain Heart Infusion (BHI). The bacterial growth was classified. Mild bacterial growth was found in group 1 at all time intervals; in group 2 there was severe growth at 7 days, but no growth at 14 and 30 days. The phytotherapeutic agent extracted from an AcOEt fraction of A. lappa inhibited the growth of all the microorganisms in this study.
