IADR Abstract Archives
Chitosan modified zinc oxide-eugenol cement increases antimicrobial activity
Objectives: Introduction: A coronal seal is essential to prevent contamination of the root canal system after endodontic treatment. Zinc oxide-eugenol (ZOE) restorative materials are used during stepwise excavation of deep caries and as a coronal seal to prevent access of bacteria to the root canal during and after endodontic treatment. The antibacterial effect of reinforced zinc oxide-eugenol is mediated by released eugenol, and varies depending on contact time and type of bacteria. Chitosan and chitosan oligomer, natural and non-toxic compound, have been reported to have an antimicrobial effect against bacteria. The aim of the study was to increase and prolong the antibacterial efficacy of ZOE materials by modification with chitosan.
Methods: Method: Low molecular weight chitosan (LMWC) and chitosan oligosaccharide (COS) powder (20 wt %) was mixed with ZOE powder (IRM, Dentsply) before eugenol was added. The material was tested fresh after setting and after immersion in water. Leakage of eugenol was measured weekly using GC-MS. Streptococcus mutans, Enterococcus faecalis and Staphylococcus epidermidis were used for biofilm experiments and direct contact test (DCT). The biofilm inhibitory effect was quantified using resazurin (10mg ml-1) on 6 hours biofilm. DCT was performed with bacteria (106) in contact with the material for 1 hour before serial dilution and plating on BHI agar. Live/dead staining confirmed dead cells on the material.
Results: Results: The amount of released eugenol was similar over a 4 week period for ZOE materials containing LMWC, COS and ZOE materials without additives. DCT and biofilm experiments showed that LMWC and COS increased the antibacterial effect of ZOE material against S. mutans and S. epidermidis. Only DCT showed antibacterial effect against E. faecalis.
Conclusions: Conclusion: LMWC and COS incorporated in ZOE materials increased the antibacterial and anti-biofilm effect against S. mutans and S. epidermidis, but did not reduce biofilm formation of E. faecalis.
Methods: Method: Low molecular weight chitosan (LMWC) and chitosan oligosaccharide (COS) powder (20 wt %) was mixed with ZOE powder (IRM, Dentsply) before eugenol was added. The material was tested fresh after setting and after immersion in water. Leakage of eugenol was measured weekly using GC-MS. Streptococcus mutans, Enterococcus faecalis and Staphylococcus epidermidis were used for biofilm experiments and direct contact test (DCT). The biofilm inhibitory effect was quantified using resazurin (10mg ml-1) on 6 hours biofilm. DCT was performed with bacteria (106) in contact with the material for 1 hour before serial dilution and plating on BHI agar. Live/dead staining confirmed dead cells on the material.
Results: Results: The amount of released eugenol was similar over a 4 week period for ZOE materials containing LMWC, COS and ZOE materials without additives. DCT and biofilm experiments showed that LMWC and COS increased the antibacterial effect of ZOE material against S. mutans and S. epidermidis. Only DCT showed antibacterial effect against E. faecalis.
Conclusions: Conclusion: LMWC and COS incorporated in ZOE materials increased the antibacterial and anti-biofilm effect against S. mutans and S. epidermidis, but did not reduce biofilm formation of E. faecalis.