Objective: In order to prolong the clinical efficacy of triclosan, we developed two pharmaceutical formulations in which triclosan is embedded in a matrix which sustained the release of the drug.
Methods: Two sustained release varnish (SRV) were formulated, which differ in their polymeric matrix. A fast SRV composed of polymethacrylates matrix and a slow SRV composed of an ethyl cellulose matrix. The release rate was examined by UV adsorption of the triclosan in the release medium. The antibacterial efficacy of the SRVs containing triclosan were tested in planktonic, batch biofilm and Constant Depth Film Fermenter (CDFF) against Streptococcus mutans.
Results: Two formulations were developed. A fast SRV in which the triclosan was released after 8 hours. The release rate was similar to the degradation rate of the polymeric matrix. The release period extended over 10 days in the slow SRV. The release rate of the triclosan followed the Higuchi model of planar diffusion (r=0.99). The antibacterial efficacy of triclosan incorporated into the sustained release varnishes was not affected as tested in agar diffusion and broth assays. The SRV of triclosan had a marked influence on bacterial viability in a batch biofilm model and tested using a confocal laser scanning microscope (Live/Dead Kit). Simulating flow conditions, we have tested the antibacterial effect of the SRV of triclosan in a CDFF. The SRV has shown a very strong effect on viability of streptococcus mutans in biofilm constructed in the CDFF. The killing effect was recorded at biofilms of 20 microns depth.
Conclusions: Our results indicate that release of triclosan can be controlled according to pharmaceutical modifications of the drug delivery. The SRV of triclosan is capable of killing bacteria in planktonic and in biofilm conditions.