Effectiveness of chitosan-propolis nanoparticle against Enterococcus faecalis biofilms in the root canal

Abstract

Background The successful outcome of endodontic treatment depends on controlling the intra-radicular microbial biofilm by effective instrumentation and disinfection using various irrigants and intracanal medicaments. Instrumentation alone cannot effectively debride the root canals specially due to the complex morphology of the root canal system. A number of antibiotics and surfactants are being widely used in the treatment of biofilms however, the current trend is towards identification of natural products in disinfection. The aim of the study was to determine the antibacterial effect of chitosan-propolis nanoparticle (CPN) as an intracanal medicament against Enterococcus faecalis biofilm in root canal. Methods 240 extracted human teeth were sectioned to obtain 6 mm of the middle third of the root. The root canal was enlarged to an internal diameter of 0.9 mm. The specimens were inoculated with E. faecalis for 21 days. Following this, specimens were randomly divided into eight groups (n = 30) according to the intracanal medicament placed: group I: saline, group II: chitosan, group III: propolis100 µg/ml (P100), group IV: propolis 250 µg/ml (P250), group V: chitosan-propolis nanoparticle 100 µg/ml (CPN100), group VI: chitosan-propolis nanoparticle 250 µg/ml (CPN250), group VII: calcium hydroxide(CH) and group VIII: 2% chlorhexidine (CHX) gel. Dentine shavings were collected at 200 and 400 μm depths, and total numbers of CFUs were determined at the end of day one, three and seven. The non-parametric Kruskal Wallis and Mann–Whitney tests were used to compare the differences in reduction of CFUs between all groups and probability values of p < 0.05 were set as the reference for statistically significant results. The scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM) were also performed after exposure to CPNs. The effectiveness of CPNs were also evaluated against E. faecalis isolated obtained from patients having failed root canal treatment. Results The treatments of chitosan, P100, P250, CPN100, CPN250, CH and 2% CHX reduced the CFUs significantly compared to saline (p < .05). On day one and three, at 200 and 400-μm, CPN250 showed significant reduction of CFUs compared to all other groups (p < .05), while CPN100 was significantly better than other groups (p < .05) except CPN250 and 2% CHX. On day seven, at 200-μm CPN250 showed significant reduction of CFUs compared to all other groups (p < .05) except CPN100 and CHX, while at 400 μm CPN250 showed similar effectiveness as CPN100, CH and 2% CHX. SEM images showed root canal dentin treated with CPN250 had less coverage with E. faecalis bacteria similarly, CLSM images also showed higher percentage of dead E. faecalis bacteria with CPN250 than to CPN100. Conclusion CPN250 was the most effective in reducing E. faecalis colonies on day one, three at both depths and at day seven CPN250 was equally effective as CPN100 and 2% CHX.

Efficacy of chitosan paste as intracanal medication against Enterococcus faecalis and Candida albicans biofilm compared with calcium hydroxide in an in vitro root canal infection model

“…Chitosan is positively charged and binds the negatively charged microbial cell membrane, while PG can help intracanal medication to penetrate deeper in dentinal tubules and it also has germicidal activity [ 20 , 39 , 40 ]. Similarly, chitosan-propolis nanoparticles was shown to be effective at eliminating E. faecalis biofilm after 7 days of medication [ 18 ]. Thus, chitosan is a promising alternative option for intracanal medication, either alone or in combination with other active ingredients, especially in infection where E. faecalis and/or C. albicans infection may play important roles.…”

“…In particular, it has been demonstrated that 1700 kDa and 2100 kDa chitosan are effective against E. faecalis, but they require a long contact time (over 1 h) [ 17 ]. Thus, we propose that these chitosan derivatives are promising to be developed into intracanal medication [ 17 , 18 ].…”

A clinical perspective of chitosan nanoparticles for infectious disease management

“…However, some of them are being investigated at the preclinical level. Chitosan–propolis nanoparticles were estimated against E. faecalis procured from patients who suffered from failed root canal treatment [ 104 ]. A preclinical analysis of bupivacaine-loaded CNPs revealed the enhanced anesthetic outcome of the payload following infraorbital nerve blockade [ 102 ].…”

Nanoparticles in Endodontics Disinfection: State of the Art

“…Chitosan is a deacetylated derivative of chitin and its structure is similar to the components of the extracellular matrix, being able to reinforce collagen constructions [ 13 ]. Chitosan is a versatile compound in terms of its forms and functions, as demonstrated by its excellent antibacterial, antiviral and antifungal properties, which has aroused great interest in biomedicine [ 120 ]. This polymer can be loaded with different active compounds such as chlorhexidine (CHX), which has produced great results in the elimination of bacteria and biofilms in specific oral diseases [ 121 ].…”