Presentation Blocks: 03-23-2018 - Friday - 11:00 AM - 12:15 PM

Title: Evaluation of Antibiotics on Immature and Mature Endodontic Bacterial Biofilm


Ji Yoo Lee (Presenter)
Indiana University

Ghaeth Yassen, Indiana University
Richard Gregory, Indiana University


Objectives: Studies have demonstrated the inhibitory effect of Double Antibiotic Paste (DAP) against biofilm formation by Enterococcus faecalis and Porphyromonas gingivalis. The purpose of this research was to investigate the inhibitory effect of DAP against biofilm formation induced by immature and mature species collected from patients with necrotic pulps.

Methods: The immature and mature species were collected using paper points from pediatric and adult patients, respectively, with root canal infections and cultured in brain heart infusion broth supplemented with yeast extract, vitamin K, and hemin (BHIY). The specific types of bacterial species that possibly make up each immature and mature species have not been fully determined, however, there was a higher number of E. faecalis in the immature preparation. Different concentrations of DAP (containing ciprofloxacin and metronidazole) in BHIY were added (0-20 mg/mL) with immature or mature bacteria and were cultured for 72 h in 96-well microtiter plates. Negative controls were prepared with the same bacterial species without DAP treatment. After incubation, a crystal violet assay was used to examine the amount of biofilm formation. Data were analyzed using two-way ANOVA.

Results: Compared to the negative controls, DAP significantly reduced (p<0.05) the biofilm formed by mature species at all tested concentrations, except at 20 mg/mL. Inhibitory effects of DAP against biofilm formation induced by immature species, however, showed no significant reduction.

Conclusions: Our preliminary results provide insight into endodontic regeneration, which is associated with root canal infections that can be eliminated using different chemical treatments including DAP. Treatment with DAP attenuated the formation of biofilm induced by mature bacterial species.


Poster Session

11:00 am–12:15 pm Mar 23 (US - Eastern)

CC, Hall B/C