Light activated disinfection: an alternative endodontic disinfection strategy

Abstract

Background: An improved light activated disinfection technique utilizing a specific photosensitizer formulation, liquid optical-conduit, oxygen-carrier and light energy of appropriate wavelength has been introduced recently. This study tested the efficacy of this improved light activated disinfection on ex vivo biofilms of Enterococcus faecalis at two different stages of maturation. Methods: Eighty-five tooth sections were prepared and endodontic biofilm of E. faecalis were grown within the root canal. In stage 1, conventional light activated disinfection (LAD), chemical disinfectant (sodium hypochlorite) and improved LAD were tested on four-day-old (immature) biofilms. In stage 2, conventional LAD, improved LAD and chemomechanical disinfection (alone and in combination with improved LAD) were tested on four-week-old (mature) biofilms. Results: Sodium hypochlorite and improved LAD showed the ability to significantly inactivate bacteria in four-day-old biofilms when compared to the control and LAD (p < 0.05). Inactivation of bacteria from deeper dentine was higher in improved LAD than sodium hypochlorite. In four-week-old biofilms, a combination of chemomechanical disinfection and improved LAD produced significant bacterial killing compared to either chemomechanical disinfection or improved LAD alone. Conclusions: This study highlighted the potential of improved LAD to kill bacteria within dentinal tubules. In combination with chemomechanical preparation, the improved LAD significantly inactivated four-week-old biofilm bacteria.

Effectiveness of high-power diode laser associated to chemical auxiliary substance on decontamination of root canal system infected with Enterococcus faecalis – an in vitro study

“…Groups G3(NaOCl+DL) and G4(CHX+DL) showed lower counting of the number of colony-forming units than all other groups, although with no statistically significant difference when compared to G1(NaOCl) and G2(CHX) where the root canals were not irradiated. Similar results were found in previous studies 6,[20][21][22] which referred that diode laser helped to reduce the number of bacteria in deep layers of infected root canal system, when associated to conventional chemo-mechanical preparation. This can be explained by the broad antimicrobial spectrum of sodium hypochlorite and chlorhexidine, demonstrated by previous studies 23,24 , as well as to the protein denaturation and photothermal action provided by high-power diode laser over the bacterial cell 25 .…”

In vitro Antibacterial Activity of Zingiber officinale and Orthosiphon stamineus on Enterococcus faecalis

“…This damage was similar to the SEM findings in this study, where changes such as pitted cell surface and disintegrated cells were seen on E. faecalis following exposure to the studied herbs. According to Lim et al (2009), hydroethanolic ginger extract exhibits potent antibacterial activity against Gram-positive and Gram-negative bacteria. In the past, essential oils had been demonstrated to be as effective as antimicrobial agents to use in oral care (Tufekci et al, 2008).…”

The Antibacterial Effect of Additional Photodynamic Therapy in Failed Endodontically Treated Teeth: A Pilot Study

“…35 MB was used according to several previous studies. 42,43,47 Regarding root canal disinfection, most of recent studies did not confirm a significant improvement for PDT as a substitute for current disinfection methods. Hence, in the present study it was used as an adjunct to the routine procedures.…”