Effect of different sealers on thermoplasticized Gutta-percha root canal obturations

The objective of this study was to test the hypothesis that the apical seal provided by thermoplasticized root canal obturations depends on the film thickness of the sealer used. The root canals of 120 maxillary cuspid teeth were instrumented and divided into six equal groups of 20 teeth. A thermoplasticized gutta-percha root canal obturator was used to make an impression of the lubricated canal and coated with a sealer cement before reseating. Five different sealer cements of known film thickness were studied. They were, in the decreasing order of film thickness, Roth's Type I Cement, Seal-apex, Lee Endofil, AH26, and Ketac-Cem. The control group that received no sealer was prepared as recommended by the manufacturer. The degree of microleakage was based on the depth of dye penetration from the apical end measured by two independent examiners. The data collected were analyzed by analysis of variance and Weibull distribution. Analysis of variance shows that the control group exhibited significantly higher dye penetration depth (p < 0.05) while there were no significant differences among the other five groups. Analysis by Weibull distribution function shows that Lee Endofil and AH26 exhibited a higher percentage of lower linear dye penetration values compared with other groups.