Photodynamic therapy (PDT) has been suggested as a potential adjunctive aid to disinfection of the root canal. In principle, it uses a nontoxic photosensitizer that is selectively absorbed in a target tissue and a low-intensity light source. Upon photo-induced activation of the photosensitizer, in the presence of oxygen, a series of reactions produce free radicals and singlet oxygen molecules leading to bacterial eradication. The aim of this review was to investigate the effect of PDT on bacteria load reduction during root canal disinfection.
Searches were conducted in PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) databases. References lists of identified articles were also searched. Randomised controlled trials, prospective clinical cohort, or crossover studies in the English language were considered. Quality assessment was conducted using the CONSORT and STROBE (Strengthening the Reporting of Observational studies in Epidemiology) statement criteria. The primary outcome was the effect of PDT on the microbial load (or number of microbial species
- Three articles met the inclusion criteria, One study was a crossover clinical study and 2 were uncontrolled clinical studies
- Because of the heterogeneity in clinical indications and PDT protocols among the included studies, a meta-analysis could not be performed
- All included studies showed a positive effect of PDT in the reduction of microbial load in root canal treatment ranging from 91.3%–100%
The authors concluded
Limited clinical information is currently available on the use of PDT in root canal disinfection. If supported by future clinical research, PDT may have efficacy for additional root canal disinfection, especially in the presence of multi–drug-resistant bacteria.
Comment
Only a small number of low quality studies were available on this topic and as the authors note only a surrogate outcome of bacterial load could be assessed rather than an improvement in clinical outcomes. The discussion sections highlights a number of adverse effects and the authors call for proper reporting of adverse events in future studies is welcomed., as is the need for well conducted randomised, controlled, clinical trials that will report clinical treatment outcomes.
Links
The Effect of Photodynamic Therapy in Root Canal Disinfection: A Systematic Review Vanessa Chrepa, Georgios A. Kotsakis, Tom C. Pagonis, Kenneth M. Hargreaves DOI: http://dx.doi.org/10.1016/j.joen.2014.03.005 Publication stage: In Press Corrected Proof Published online: May 1, 2014