Introduction: The aim was to evaluate the suitability of paper points or endodontic nickel-titanium files to sample microorganisms for in vivo investigation of endodontic microbiota by 16S ribosomal DNA (rDNA) sequencing.
Methods: Forty-five patients presenting clinical and radiological signs of apical periodontitis were recruited for sampling, giving their written informed consent. Glide paths were assessed using C-Pilot Files and K-Files under electronic root canal length control under aseptic conditions.