In vitro evaluation of four methods of sealer placement.

Sealer is required during root canal obturation, although no studies have shown which method of sealer placement provides the best coverage. This study evaluated and compared four methods of sealer placement: file, lentulo spiral, ultrasonic files, and master gutta-percha cone. Forty mandibular incisors were prepared by a step-back technique. AH26 (0.04 ml) was applied to the placement device, the sealer was placed in the canal, and the canal was obturated with lateral condensation of gutta-percha. The specimens were cleared and evaluated for the presence of the sealer in the apical, middle, and coronal thirds of the canal. The results showed no statistically significant differences among the four groups. The greatest variation in sealer coverage was found in the apical level. Sealer coverage in the coronal and middle thirds was nearly identical regardless of sealer placement technique.