Post preparation techniques and their effect on the apical seal.

It is accepted clinical procedure to extend post preparations to such a depth that 3 mm to 5 mm of gutta-percha remains at the apex of the tooth. Clinicians use numerous techniques to achieve this goal. This investigation quantitatively analyzed the effect of the method of gutta-percha removal on the apical seal and evaluated apical leakage in teeth with different levels of remaining gutta-percha. The methods evaluated included the GPX instrument, heated pluggers, and Gates-Glidden drills. Groups of 25 extracted teeth were prepared with each of the three methods leaving 3 mm or 5 mm of gutta-percha remaining apically. Spectrophotometry (optical density) was used to assess apical leakage. Significantly less leakage was observed with the heated plugger technique at the 3 mm and 5 mm levels when compared to the 3 mm and 5 mm levels in both the GPX and Gates-Glidden groups.