Evaluation of apical seal in endodontically filled teeth using different root canal preparation techniques

الملخص EN

Background : The main objectives of endodontic treatment are to remove the contents and irregularities from the root canal, and to shape the canal to facilitate placement of the obturating materials.

Aims of the study were to evaluate the effect of different instrumentation techniques on spreader penetration depth, and to evaluate the effect of the spreader penetration depth on the apical seal using stainless-steel and nickel-titanium finger spreaders.

Methods and Materials : Eighty extracted human teeth, with single and curved canals, were prepared by step-back, stepback with Gates-Glidden burs, crown-down pressureless and standardized-taper root canal preparation techniques.

All teeth were obturated with gutta percha and sealer using stainless-steel and nickel-titanium finger spreaders for lateral condensation, the depth of spreader penetration was measured.

The apical 3-4 mm of all teeth was submerged in Pelikan ink for 48 hours then splitted longitudinally for linear measurement of dye penetration through the apical foramen.

Results : Step-back with Gates-Glidden technique scored the least differences in spreader penetration depths and dye penetration, when compared with step-back technique, crown-down pressureless technique, and standardized-taper technique.

Standardized-taper technique showed statistically greater differences concerning spreader penetration depth and apical microleakage.

No significant differences were found between step-back and crown-down pressureless techniques.

Highly significant differences were evident when nickel-titanium and stainless-steel spreaders were compared in the stepback technique, step-back with Gates-Glidden technique, and standardized-taper technique, and there was a significant difference when they were compared in crown-down pressureless technique.

Conclusions : Regarding the differences between spreader penetration depths and apical leakage, step-back technique with Gates-Glidden burs scored the best results when it was compared to the other groups.

The quality of the apical seal was related directly to the method of canal preparation.

Step-back with Gates-Glidden technique, which permitted deeper penetration of the spreader, resulted in a seal closer to the prepared length.

Nickel-titanium spreader penetrated deeper and provided better apical seal than stainless-steel spreader.