Comparative Evaluation of Efficacy of Gutta-Percha Removal in Root Canal Retreatment Using Manual and Rotary...

Effective removal of gutta-percha is critical for successful root canal retreatment. While manual and rotary instrumentation techniques are commonly employed, their comparative efficacy remains a topic of debate.

An in vitro study was conducted on 72 extracted single-rooted premolars, decoronated to 13 mm, and obturated with gutta-percha. Samples were divided into three groups (n = 24) and retreated using Hedstrom files, D-Race, or NeoEndo systems with Endosolv solvent. Residual gutta-percha, time to reach working length, and total removal time were evaluated.

Group II (D-Race) showed the least residual gutta-percha (10.8%) compared with Group I (H-files) with 15.2% and Group III (NeoEndo) with 12.0%. Time to reach working length was significantly lower in D-Race (45.2 sec) and NeoEndo (48.8 sec) than manual files (60.5 sec). Total removal time followed a similar trend: D-Race (150.0 sec) < NeoEndo (160.0 sec) < H-files (180.0 sec). ANOVA results were significant (P < 0.001) across all parameters. Effect sizes indicated large clinical differences between manual and rotary groups. Strong correlations were observed between residual gutta-percha and procedural times (r = 0.65-0.80).

Rotary retreatment instruments, particularly the D-Race system, demonstrated significantly superior cleaning efficacy and time efficiency compared with manual Hedstrom files. The NeoEndo system also performed better than manual methods.