The comparison of penetration depth of two different photosensitizers in root canals with and without smear layer: An in vitro study

• ICG can penetrate in deeper regions of the root canal wall.
• The creation of new methods in root canal disinfection in order to improve the success rate of our treatment is necessary.
• The usage of EDTA improved the mean of lateral penetration depth of ICG.

BackgroundThe main objective of this study is to evaluate the penetration depth of suggested photosensitizers in the lateral wall of the human root canal.Materials & methodsForty extracted single-rooted human teeth with straight canals that extracted for periodontal reasons were collected and stored in the sterile saline until employment in the experiment. Teeth were decoronated to a standard 12 mm root segment using diamond disc. After instrumentation of specimens, the external root surface was sealed with two layers of nail polish to avoid environmental contamination. The apical foramen was subsequently closed with composite material. Teeth were divided randomly in two major groups consist of indocyanine green solution (ICG) and tolonium chloride solution (TCH) with and without EDTA in their subgroups. Specimens in all groups grooved longitudinally with a diamond disc and split in two halves with a stainless steel chisel. The measurements were done by the stereo microscope under 20× magnification in three zones of each specimen and the penetration depth of dye was measured.ResultsThe results of this study showed that the mean of lateral penetration depth of ICG (224.04 μm) was significantly (P < 0.05) higher than TCH (70.15 μm). Regarding to the influence of EDTA, in ICG group without consideration to the different regions, the usage of EDTA improved the mean of lateral penetration depth of ICG, but this improvement was not statistically significant (P > 0.05).ConclusionFurther to the findings of this study, it could be assumed that ICG could penetrate in deeper regions of the root canal wall.