A clinical case of a necrotic UR6 associated with periapical periodontitis

Curved and sclerosed canals can raise difficulties for the operator during root canal treatment resulting in iatrogenic errors. In this case challenging root canal anatomy in a maxillary molar (UR6) was successfully negotiated using a methodical approach and reciprocating nickel titanium instruments.

Clinical examination

A 56 year-old man was referred for root canal treatment of his UR6 after his general dentist had been unable to locate or negotiate sclerosed canals in the painful tooth.

Intraorally, there were no swelling, sinus tracts, visible cracks or increased periodontal pocketing. The tooth was restorable, but the existing amalgam restoration was defective. The tooth was non-vital to sensitivity testing with Endo-ice (Coltene).

Radiographic assessment using a paralleling periapical radiograph (Rinn, Dentsply Sirona) showed a large amalgam restoration distally, with poor marginal integrity. There was evidence of access cavity preparation and removal of dentine overlying the disto-buccal (DB) canal. The DB and palatal canals appeared patent but the mesio-buccal (MB) canals had not been located or negotiated and the MB root was significantly curved. There was evidence of periapical radiolucency.

There were no discernible signs of periodontal disease or gross caries.


A necrotic UR6 associated with periapical periodontitis.

Treatment options

Sensible treatment options for a necrotic UR6 associated with periapical periodontitis in this case include:

  • Non-surgical root canal treatment, followed by placement of a cusp-coverage restoration.
  • Extraction only or replacement with an implant or bridge.
  • Extraction and replacement with an implant should be feasible, but may require bone augmentation.

The natural tooth was eminently restorable and a good root filling complimented with a well-fitting crown could be expected to function as well as an implant supported crown, for significantly less cost and surgery time (Torabinejad et al, 2007; Hannahan and Eleazer, 2008; Pennington et al, 2009).

Treatment for necrotic…

Register to access the full article & more exclusive content

Sign up to receive free access to a range of premium articles, podcasts, webinars and enhanced CPD.

Register Login

Become a Dentistry Online member

Become a member
Add to calendar