Evaluation of Gutta-Percha Removal by Orange Oil Solvent and Eucalyptus Solvents Using Protaper Universal and XP-Endo® Rise Retreatment Instrument (An Invitro Comparative Study)

Objective: This study evaluated the effectiveness of two rotary retreatment file systems with two gutta-percha solvents using Cone Beam Computed Tomography (CBCT) with Civil 3D 2020 metric software program during the root canal retreatment procedure. Methods: Forty extracted human permanent premolars had roots filled with guttapercha and were divided into four groups. The first two groups were retreated using the ProTaper universal rotary system with orange oil or eucalyptus solvent (A1, A2), while the other two groups were treated with Xp endo retreatment with the same solvents (B1, B2). A CBCT scan was taken before and after the root canal retreatment procedures to measure the amount of residual gutta-percha filling materials in the apical, middle, and coronal thirds. The amount of removed guttapercha was calculated by subtracting the before from the after measurements. The data was subjected to statistical analysis; P-values below 0.05 were considered statistically significant. Results: The amount of filling material removed at the coronal third was statistically nonsignificant between study groups (p= 0.544); in the middle third, there was a statistically significant difference between the groups (p= 0.043), and according to Tukey HSD, significance between A1 and B2 groups. Regarding the apical third there was a statistically significant difference between the groups (p= 0.017) and the significance was found between A1 and B1 groups. Conclusions: The ProTaper endo shaper rotary retreatment files are more efficient in removing root-filling materials than the Xp endo shaper. However, the type of solvent had no impact on the current study's results.