Effectiveness of halothane used with ultrasonic or hand instrumentation to remove gutta-percha from the root canal

This study compared halothane and chloroform used with hand or ultrasonic instrumentation to remove gutta-percha and sealer from root canals. Apically extruded debris, residual debris, time for filling removal, and amount of solvent used were determined. The differences in extruded apical debris and radiographically visible residual debris were not significant (p greater than 0.05). Ultrasonic instrumentation required significantly less time to remove the root canal filling than did hand instrumentation (p = 0.02). The only significant difference in the amount of solvent used occurred when the ultrasonic-chloroform group was compared with the hand instrumentation-chloroform group (p = 0.05). Halothane was found to be an acceptable alternative to chloroform for removing gutta-percha and sealer from the obturated root canal.