ENDODONTIC RETREATMENT OF THERMAFIL VERSUS LATERALLY CONDENSED GUTTA-PERCHA

The Thermafil device is becoming a popular obturating material. Becaus e endodontic failures inevitably occur with all techniques, questions of retreatment of Thermafil-obturated teeth will also arise. The purpo se of this study was to compare retreatment of Thermafil and laterally condensed gutta-percha. Thirty-five mandibular incisors were prepared with a stepback flare technique and divided into two groups. One grou p (n = 20) was obturated using Thermafil, the other group (n = 15) was obturated with laterally condensed gutta-percha. The teeth were store d in a humidor for 3 months to allow sealer to set. Retreatment of bot h groups was accomplished using a combination of heat and chloroform s olvent. The time for retreatment was recorded. The teeth were split lo ngitudinally and the amount of gutta-percha remaining in the root cana l was measured and analyzed statistically. The results showed that in the coronal one-third of the canal, use of the Thermafil device result ed in significantly more remaining gutta-percha than use of laterally condensed gutta-percha. However, in the apical and middle one-third of the canal the difference in remaining gutta-percha between Thermafil and laterally condensed gutta-percha was not significant. The metal ca rrier was easily removed and the mean time for retreatment was 6.3 min for Thermafil compared with 5.7 min in the lateral condensation group .