Effectiveness of different gutta-percha techniques when filling experimental internal resorptive cavities

To determine the quality of root fillings in teeth with artificial internal resorptive cavities filled with Thermafil, JS Quick-Fill, Soft Core, System B and Microseal, and by cold lateral compaction (LC) technique.

Sixty maxillary incisor teeth were selected. After access cavity preparation and root canal instrumentation, the roots were sectioned horizontally and artificial internal resorption cavities were prepared on the canal walls. The tooth sections were cemented together and the root canals were filled using one of six different techniques: Thermafil, JS Quick-Fill, Soft Core, System B and Microseal, and by LC. The roots were then divided at the level of the previous section and each root surface was photographed. Image analysis program was used to calculate the percentage of sealer, gutta-percha and void in the internal resorptive cavities. All measurements were analysed statistically using One-way ANOVA and Newman-Keuls tests.

The Microseal technique filled 99% of the artificial resorptive area followed by LC (92%), SystemB (89%), Quick-Fill (88%), Thermafil (74%) and Soft-Core (73%). Warm gutta-percha compaction techniques filled the resorption areas with more gutta-percha than sealer (Microseal 68%, System B 62%) compared to the other techniques (LC 48%, Quick Fill 41%, Soft Core 34%, Thermafil 35%). In addition, core techniques left a considerable volume of voids in the resorptive areas (Quick-Fill 12%, Thermafil 26%, Soft Core 27%).

Warm gutta techniques filled artificial resorption cavities significantly better than the other gutta-percha techniques.