Recent advances in endodontic irrigation: FESEM analysis

OBJECTIVES. The aim of this work is to evaluate the cleansing properties of four different root canal irrigants in extracted dental elements, using the scanning electron microscope (Field Emission Scanning Electron Microscope, FESEM). MATERIALS AND METHODS. Twenty single-rooted dental elements, extracted for periodontal reasons, were subjected to biomechanical bore and canal irrigation through four different tested solutions, namely: irrigant 1 sodium hypochlorite (NaOCl) at 5%; irrigant 2, cetrimide + chlorhexidine (Cetrexidin, Gaba Vebas, Rome, Italy); irrigant 3, ethylenediaminetetraacetic acid (EDTA); irrigant 4, doxycycline + citric acid + polypropylene glycol (Tetraclean, Ogna Laboratori Farmaceutici, Muggi', MB, Italy). All the samples, after proper dehydration and metallization, were observed through the FESEM (Supra™, Carl Zeiss Microscopy GmbH, Jena, DE) to evaluate the cleansing level achieved in the middle and apical thirds of the canal. RESULTS. The results of our study showed that the irrigant 2 had an excellent cleansing power in the middle third of the canal, although less effective in the apical third. The cleansing power of irrigants 1 and 3 proved to be good enough in the middle third of the canal, although lower than irrigant 2; modest was the cleansing power in the apical third, with special regard to smear-layer removal. Irrigant 4 didn't show any good cleansing capacity, neither in the middle third, nor in the apical third of the canal. CONCLUSIONS. The irrigation practice seems to play a key role in the success of the canal therapy. However, it is not recommendable to use one only irrigating solution in the course of an endodontic treatment. Consequently, using more irrigating solutions at the same time, each with a specific role in endodontic cleansing, seems to be the only viable way to achieve a successful treatment outcome.