Photoactivated disinfection (PAD) of dental root canal system - An ex-vivo study

Saudi J Biol Sci. 2016 Jan;23(1):122-7. doi: 10.1016/j.sjbs.2015.01.013. Epub 2015 Jan 27.

Abstract

Aim: To investigate the efficacy of photo activated disinfection (PAD) in reducing colony-forming unit (CFU) counts of Enterococcus faecalis (E. faecalis) in infected dental root canals. The study compared the efficacy of PAD with conventional endodontic treatment (CET) and also a combination of CET along with PAD.

Material and methods: 53 maxillary incisors were taken for the study. Teeth were divided into 3 groups, CET (Group I) (n = 11), PAD (Group II) (n = 21), and a combination of CET and PAD (Group III) which consisted of (n = 21) samples, Group II and Group III were further divided into 2 subgroups, Group IIa, IIb and Group IIIa, IIIb. Strains of E. faecalis were inoculated in all the root canals. CET group samples were treated by chemo-mechanical preparation (CMP) alone, PAD samples were treated with laser alone at 2 different exposure time (4 min and 2 min). In the combination treatment, samples were treated initially by CET and then by PAD for a time period of 4 min and 2 min. Contents of the root canal were aspirated, diluted and plated in Tryptone Soya Broth (TSB) and plates were incubated for 24 h to observe the bacterial regrowth.

Results: Showed PAD used along with CMP reduced the bacterial load of E. faecalis by 99.5% at 4 min and 98.89% at 2 min.

Conclusion: PAD may be an adjunctive procedure to kill residual bacteria in the dental root canal systems after standard endodontic root canal preparation.

Keywords: Chemo-mechanical preparation (CMP); Colony forming unit (CFU); Conventional endodontic treatment (CET); Photo activated disinfection (PAD); Photosensitiser (PS); Tryptone Soya Broth (TSB) agar medium.