Background: Post-treatment apical periodontitis are persistent infections in tissues surrounding
teeth roots, which are the consequence of an endodontic treatment failure. These secondary
diseases are mainly caused by etiological pathogens from endodontic origin, especially Enterococcus
feacalis and Candida albicans. Currently, post-treatment apical periodontitis become a
serious problem for dentists where researches are accented particularly for the development of new
antiseptics (known as irrigation solutions).
Objective: To propose an alternative irrigation solution based on Cinnamomum cassia essential oil
diluted in ethanol.
Method: C. cassia essential oil, chemically analyzed by GC/MS, and prepared in 20% ethanol, was
evaluated for antimicrobial activity and total eradication of E. faecalis and C. albicans biofilms. The
most used irrigation solutions by dentists, namely chlorhexidine digluconate and sodium hypochlorite,
were also evaluated for comparison. Obtained data were analyzed statistically using two-way
analysis of variance (ANOVA) followed by Bonferroni's test.
Results: The obtained results revealed that C. cassia essential oil, consisting mainly of 75% cinnamaldehyde,
has shown a strong antimicrobial activity against the studied microbial species whatever
their grouping in biofilms or planktonic. In an irrigation assay carried out in vitro, 1.25% C.
cassia essential oil has eradicated all E. faecalis and C. albicans viable cells protected in biofilms
after 30 seconds of exposure only, while 2% chlorhexidine digluconate and 2.5% sodium hypochlorite
requires one and five minutes for the total elimination of studied pathogens, respectively.
Conclusion: essential oils prepared in ethanol, in general, are interesting antiseptics which can be
used as alternative irrigation solutions for endodontic treatments. C. cassia essential oil is a good
example because of its strong antimicrobial activity against biofilms of etiological pathogens responsible
for post-treatment apical periodontitis.