Title |
Antibacterial effects of N-acetylcysteine against endodontic pathogens |
Author |
Ji-Hoi Moon1,2, Young-Suk Choi1,3, Hyeon-Woo Lee2, Jung Sun Heo1,2, Seok Woo Chang4, and Jin-Yong Lee1,2* |
Address |
1Department of Maxillofacial Biomedical Engineering, School of Dentistry, Kyung Hee University, Seoul 02447, Republic of Korea, 2Institute of Oral Biology, Kyung Hee University, Seoul 02447, Republic of Korea, 3Department of Dental Hygiene, Shinsung University, Chungnam 31801, Republic of Korea, 4Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul 02447, Republic of Korea |
Bibliography |
Journal of Microbiology, 54(4),322-329, 2016,
|
DOI |
10.1007/s12275-016-5534-9
|
Key Words |
N-acetylcysteine, endodontic pathogens, multispecies biofilm, antibacterial, biofilm disruption |
Abstract |
The success of endodontic treatment depends on the eradication
of microorganisms from the root canal system and
the prevention of reinfection. The purpose of this investigation
was to evaluate the antibacterial and antibiofilm efficacy
of N-acetylcysteine (NAC), an antioxidant mucolytic
agent, as an intracanal medicament against selected endodontic
pathogens. Minimum inhibitory concentrations (MICs)
of NAC for Actinomyces naeslundii, Lactobacillus salivarius,
Streptococcus mutans, and Enterococcus faecalis were determined
using the broth microdilution method. NAC showed
antibacterial activity, with MIC values of 0.78–1.56 mg/ml.
The effect of NAC on biofilm formation of each bacterium
and a multispecies culture consisting of the four bacterial species
was assessed by crystal violet staining. NAC significantly
inhibited biofilm formation by all the monospecies and multispecies
bacteria at minimum concentrations of 0.78–3.13
mg/ml. The efficacy of NAC for biofilm disruption was evaluated
by scanning electron microscopy and ATP-bioluminescence
quantification using mature multispecies biofilms.
Preformed mature multispecies biofilms on saliva-coated hydroxyapatite
disks were disrupted within 10 min by treatment
with NAC at concentrations of 25 mg/ml or higher.
After 24 h of treatment, the viability of mature biofilms was
reduced by > 99% compared with the control. Moreover, the
biofilm disrupting activity of NAC was significantly higher
than that of saturated calcium hydroxide or 2% chlorhexidine
solution. Within the limitations of this in vitro study, we
conclude that NAC has excellent antibacterial and antibiofilm
efficacy against endodontic pathogens and may be used as an
alternative intracanal medicament in root canal therapies. |