Forty extracted teeth were instrumented using a step-back flare technique and obturated
with gutta-percha and either AH26 or Roth's 801 sealer. After 3 months the canals were
retreated by removing gutta-percha and sealer with hot instruments followed by chloroform
and files. As a final step, the teeth were instrumented using ultrasonics with either chloroform
or with NaOCl. Most teeth were well cleaned. No significant differences were found between
sealer groups or between the two irrigants as to the ability to remove gutta-percha/sealer.

Endodontic retreatment : ultrasonics and chloroform as the final step in reinstrumentation |
CiNii Research … Endodontic retreatment : ultrasonics and chloroform as the final step in
reinstrumentation …