Fig. 1

Cases with anatomic root canal impediments (abrupt curvatures) in distal canals of lower molars.

Fig. 2

Iatrogenic impediment - ledged mesial canals of lower molar with significant ledge in mesiolingual canal (arrow).

Fig. 3

Gutta-percha and rotary file precurved in the same direction.

Fig. 4

Pre-operative radiograph tooth #47.

Fig. 5

Endo ice spray is of great help in making gutta-percha points stiffer.

Fig. 6

Post-operative radiograph demonstrating significant ledge in mesial canals.

Fig. 7

Cone-fit radiograph. Gutta-percha points stopping at the impediment level short of working length.

Fig. 8

Thermafil technique in regular cases. Excess gutta-percha at the tip of the carrier is removed to minimize the risk of overfilling. The tip of the plastic carrier should be visible.

Fig. 9

Modified thermafil technique. Gutta-percha at the tip of the carrier is not removed.

Fig. 10

Post-operative radiograph. Carriers stopped at the impediment level but gutta-percha and sealer were pushed 2-3mm ahead.

Fig. 11

Post-operative radiograph, different angulation.


Endodontics clinicians should be familiar with different obturation techniques and their modification in order to achieve predictable outcomes and successfully solve a variety of everyday cases.


  1. Roda RS, Gettleman BH: Nonsurgical retreatment. In: Hargreaves KM, Cohen S, editors. Cohen’s pathways of the pulp, ed 10. New York: Elsevier; 2011. 
  2. Cantatore G, Johnson B: The thermafil system. In: Castellucci A, editor. Endodontics, Vol. II. Florence: Tridente S.r.l; 2006.
  3. Buchanan LS: Managing severe canal curvatures and apical impediments: an endodontic case study, Dent Today; 2005.