Fig. 1

The procedures for endodontic nonsurgical retreatment can be grouped into disassembly, access to missed ana­tomy, shaping and disinfection of the canal system, and obturation. While cleaning, shaping and disinfecting the root canal space in re­treatment can be similar to initial root canal therapy, location and treatment of missed anatomy, disassembly are complex procedures that require a specialized armamentarium and knowledge. The dental operating microscope allows clinicians to visualize the contents of canals and endodontic access preparations better than with loupes or the naked eye,and supports delicate retreatment procedures that cannot be accomplished by other means. 

Without the dental operating microscope and CBCT imaging, retreatment at the highest level is difficult — and sometimes impossible — to achieve.

Fig. 2

Post retrieval requires careful use of ultrasonic instruments to remove surrounding core material and disrupt the intracanal cement seal around the post. Care must be taken to avoid overheating the post because heat transmitted to the ligament during post removal may cause large areas of bone destruction and tooth loss. 

Intermittent application of the ultrasonic tip, along with copious air/water coolant spray, are necessary. There are numerous other instruments and techniques that can aid in the removal of a post, and the clinician should have training in, and access to, a wide selection to be able to retrieve posts in all situations

Stieglitz forceps is used to grip and unthread screw post in an anticlockwise direction.  Small, gentle, alternating rotations should be used along with adequate finger support buccally/labially and palatally to help detect any tooth movement.

Following post retrieval, removal of preexisting root filling materials is necessary. The technique varies depending on the materials found in the canals. Retreatment files from D-Perfect were used in this case.

After disassembly is complete, canals should be cleaned thoroughly and shaped for reception of new obturation materials. You can see clearly the deep split in the distal root after complete debridement and cleaning.

Fig. 3


The final step in retreatment is to thoroughly disinfect and three-dimensionally obturate the canal space.

Fig. 4

Academically: I Obtained my PhD degree in Endodontics from Faculty of Dentistry, Ain shams University, Egypt in 2021.

Clinically: My Master thesis has been focused on the ability of different types of posts to reinforce endodontically treated teeth (an in vitro study)
My PhD thesis has been focused on the evaluation of bacterial reduction and post operative

pain after cleaning and shaping of root canals with single file systems used in different kinematics. an in vivo study
Research activities: I have published many articles in Scopus index journals which included the Master and PhD articles.


  • Non-surgical root canal retreatment can be done perfectly before moving to the surgical approach.
  • Missed canals are considered one of the most causes of endodontic failure.
  • Three dimensional filling of the root Canals is necessary to obtain favorable outcomes.


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