Evaluation of a solvent-softened gutta-percha obturation technique in curved canals

The purpose of this study was to compare the efficacy of three obturation techniques in curved canals. Twenty-four sets of three (triplets) morphologically similar molars having root curvatures of 45 to 90+ degrees were assembled. Following canal preparation, one sample from each group was obturated by either a halothane-dipped, a chloroform-dipped, or an untreated lateral condensation technique. Twenty triplets were cleared, evaluated, and graded for homogeneity of fill, canal wall adaptation, and replication of internal anatomy. Four triplets had windows prepared to expose the apical 6 mm of filling and were viewed with scanning electron microscopy. Kruskal-Wallis test of cleared teeth indicated a significant difference in favor of the solvent-softened techniques (p = 0.01). There was no difference between chloroform- and halothane-dipped groups (p = 0.03). Scanning electron microscope evaluations of halothane-dipped samples revealed more homogeneous fills with greater canal replication than untreated gutta-percha. In addition, halothane-treated samples had appreciably less surface porosity than chloroform. Lateral condensation of halothane-treated gutta-percha was judged to be a viable obturation technique.