Cleaning Ability of Irrigants and Orange Oil Solvent Combination in the Removal of Root Canal Filling Materials

This study investigated the influence of different irrigants and the use of orange oil solvent in the removal of filling materials during root canal retreatment. Forty maxillary premolars were shaped using the ProTaper System up to file F3 (size 30, 0.09 taper) and filled by Tagger's hybrid technique using the AH Plus. Samples were randomly assigned to four groups (n=10) according to the irrigating protocol during endodontic retreatment with the ProTaper Universal Re-treatment System: G1, 2% chlorhexidine (CHX) gel; G2, 2% CHX gel with an orange oil solvent; G3, 5% sodium hypochlorite (NaOCl); and G4, 5% NaOCl with an orange oil solvent. Afterwards, the samples were longitu-dinally split into two halves, and the root wall images were prepared by scanning electron microscopy. Two pre-calibrated evaluators analyzed the images using a filling materials remnants score system. Data were statistically analyzed using the Kruskal-Wallis and Dunn's tests (pG1=G3. No statistical differences were found when the CHX and NaOCl were used (p>0.05). Groups in which a solvent was used showed a less effective cleaning ability (p