Chitosan is a carbohydrate polymer derived from chitin with a reported antimicrobial effect against bacteria. The present study aimed to investigate the biofilm inhibitory effect of methacrylated chitosan covalently incorporated into the polymethylmethacrylate polymeric network of a denture base resin.


Methacrylated chitosan was synthesized by reacting low molecular weight (LMW) chitosan with methacryloyl chloride under acidic conditions and characterized by proton nuclear magnetic resonance spectroscopy. The modified chitosan powder (20 wt%) was mixed with benzoyl peroxide (Major Prodotti Dentari S.p.A) prior to addition of methyl methacrylate (Major Prodotti Dentari S.p.A), and homogenous sample disks were prepared. The biofilm inhibitory effect was investigated using Streptococcus mutans UA159, grown in BHI for 24 hours before quantification of the biofilm was performed using resazurin (1% solution). The effect of the modified material was compared to that of denture base disks containing LMW chitosan and no chitosan (control).


The degree of methacrylation of chitosan was 16% as confirmed by 1H NMR spectroscopy. Biofilm studies showed that denture base material containing methacrylated chitosan (20 wt%) reduced biofilm formation of S. mutans 2-fold compared to LMW chitosan and 2,5-fold compared to the control.


Denture base resin incorporated with methacrylated chitosan reduced biofilm formation of S. mutans. Future studies will investigate the anti-biofilm effect against Candida albicans and the impact on the mechanical effects of the modified biomaterial.

Poster presentation at IADR General Session in Soul, Republic of Korea, June 24, 2016.

Ida Sofia Stenhagen (Presenter), NIOM
Håkon Valen, NIOM
Inger Sofie Dragland, NIOM
Hilde Kopperud, NIOM