Oda DF, et al. - Investigators examined the data to delineate the ability of carbopol gel in the maintenance of intensity of a LED curing light (blueLED) along the length of prepared root canals in bovine teeth, and also to estimate the antimicrobial capability of curcumin photoactivated by a LED curing light in the presence of carbopol gel. Using Enterococcus faecalis (ATCC 4083) at 10⁹ cells mL⁻¹, they induced biofilms for 21 days on the blocks. They observed no improvement in the intensity of LED light transmission along the root canal with carbopol gel in an experiment. But, in another experiment, they noticed a decline in bacterial viability as per following sequence: positive control < only LED curing light < only curcumin < curcumin + LED curing light = standard PDT. Overall, they did not record a favorable outcome with carbopol gel use in transmission of LED light along the root canal. Less bacterial killing was also concluded when used in endodontic PDT.