Fig. 1

Pre-operative Radiographic examination revealed;

  • Large and broken old amalgam restoration
  • Radiographic sign of access over-preparation 
  • short root fills in all the three canals, with extremely short mesio-lingual Gutta percha.
Fig. 2

The first step was to remove the Old Amalgam restoration, after proper isolation of the tooth. Remnants of gutta percha and sealer in the pulp chamber in the was removed using medium powered ultrasonics with intermittent coolant under magnification.

Softening of the coronal portion of Gutta Percha in the MesioBuccal and the distal Root canals were also done using the medium powered ultrasound, followed immediately by the BULL (Y) File [25/.07] operated in EndoMASTER Bluetooth Motor, using ATR mode (450 rpm, 2.5 N.cm, 150/30 CW/CCW, when torque limit is exceeded).

 

Fig. 3

There was a block in the ML canal, therefore the short GP filling was removed using thin ultrasonic tip

 

To Manage the ledge in the ML canal, Inner Wall modification was performed using a thin and pre-curved ultrasonic tip, operated at low power, under high magnification… to remove debris, EDTA 17% was used every 10-15 seconds to improve visibility under the dental operating microscope.

Following the inner wall modification, direct access to the mesiolingual canal was achieved using a #10 D-File from perfect Endo. Working length determination was determined using The Endo Master Built-in Apex locator. Manual glide path was then created and secured until a super-loose #10 K in all canals.

Fig. 4

The Retreaty Sequence used in the case

The Root canal System was confirmed to be confluent. Irrigant activation was performed using Ultra-Dancer Activator. Using the Ultrasonic activation loosened some gutta percha remnants from the distal canal walls, which could be retrieved using a Hedström file. Ultrasonic activation continued in the final rinse protocol as well, activating both full strength NaOCl and EDTA 17% prior to obturation.

Obturation was performed using modified warm compaction using GP-Flow heat carrier and 

Subsequent back-filling.

Fig. 5

The Radiographic Workflow

Conclusions

When dealing with Anatomy, variability is the rule. This is the reason that the endodontic practitioner must be cautious not to create any alteration of the anatomy (such as ledges, or transportations), as it will affect the treatment outcome

The introduction of New files systems like ReTreaty, which is designed to address different parts of the root canals system in a minimally invasive, yet efficient manner, allowed the clinician to manage different retreatment cases cases with an excellent margin of safety and predictability

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