Fig. 1

The patient’s chief complaint was a spontaneous pain aggravated by pressure on mastication, on the second upper right molar. Lateral and vertical percussion were positive on that tooth and negative on both the upper first and second premolar.

Upon radiographic examination, the distal and palatal canals presented short fillings with numerous voids and a broken file was detected in the mesial root. 

The diagnosis of an apical symptomatic periodontitis was established. The decision of a non surgical retreatment was taken.

After access cavity refinement using ultrasonic tips, Explora (Deppeler, La pièce 6, Swizerland) was used to explore the canals. 

3 canals were detected and the hardness of the filling material was assessed with explorer. The use of any solvent was discarded, since the old material was rather soft

The filling material was removed from the palatal and the disco-buccal with  XP-Endo Shaper without the use of any solvent

A direct access was established to the broken file in the mesio-buccal canal with a heat treated NiTi file in reciprocation, R-Motion 25 and the file was retrieved with an ultrasonic tip ET25

After the removal of the broken file, a ledge was discovered in the mesio-buccal canal. The ledge was pointed  precisely with the long Explora  (Deppeler) on the buccal wall of the canal and the orifice of the canal was also detected under magnification X10

According to the position of the ledge, a number 08 preserved C pilot file was introduced in the canal with a watch winding motion till the apical patent was secured. The working length was taken using an apex locator. 

The mesio-buccal canal was shaped with a single reciprocating file R-Motion 25

The disto-buccal and the palatal canals were shaped exactly with the same protocol 

Fig. 2

A working length X-ray showed the presence of material remnants in the mesial wall of the palatal canal

ExtEndo (Deppeler) was used to remove passively some of the remnants under magnification 

Activation of the irrigation solution was performed with the XP-Endo Finisher with 1000 RPM and 1 minute in each canal

Fig. 3

An X-ray showing the removal of the broken file and the cleanness of the walls after the retreatment procedure 

Fig. 4

The 3 canals were filled with warm vertical continuous technique for down pack and Prexo M (Deppeler) for manual compaction

The continuous wave technique was applied in all 3 canals  

Back pack was done with the injecting technique using the back fill wireless device 

Access cavity after the 3D obturation 

Fig. 5

Final X-ray after 3D filling of the entire Endodontic system 


During the retreatment procedure, regaining the anatomy and cleaning the entire endodontic system is necessary for a better long term prognosis of the tooth. This will suppose the removal of the entire filling material, the retrieval of any fractured instrument and the bypass of ledges. A long and sharp explorer such as Explora will give us the possibility to detect precisely the location of the ledge, and accordingly to bypass it first with small hand files and after with NiTi files. Finally, a warm vertical continuous technique will assure the longevity of the treatment.


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