Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals

Aim: To compare the efficacy of the XP-endo finisher file (XP) (FKG Dentaire, La Chaux de Fonds, Switzerland) to that of passive ultrasonic irrigation (PUI) and conventional syringe and needle irrigation (SNI) in the removal of calcium hydroxide paste from an artificial standardized groove in the apical third of root canals.

Methodology: The root canals of 68 mandibular incisors with single oval canals were prepared using Mtwo instruments (VDW GmbH, Munich, Germany) up to size 40, .04 taper. Each tooth was split longitudinally, and in one half of the root, a standardized groove was prepared in the apical part of the specimen. The grooves were filled with Ca(OH)₂ , and the root halves were reassembled. The roots were randomly divided into two control groups (n = 4) and three experimental groups (n = 20) according to the Ca(OH)₂ methods used: XP, PUI and SNI. The amount of remaining medicament was evaluated under X25 magnification using a 4-grade scoring system. Kappa values were calculated for intra- and interobserver agreement evaluation. The differences in the Ca(OH)₂ scores amongst the different groups were analysed using the Kruskal-Wallis test.

Results: None of the tested methods could completely clean the Ca(OH)₂ from the artificial standardized groove in the apical third of the root canals. XP and PUI removed significantly more Ca(OH)₂ than SNI (P < 0.001), with no significant differences between them (P = 0.238).

Conclusions: XP and PUI were more effective in removing Ca(OH)₂ from artificial standardized grooves in the apical third of root canals than SNI.