The 46 did not respond to electric pulp or cold thermal vitality testing, the 44 and 45 responded positively to vitality testing.
What did the radiograph reveal about the 46?
- A well defined periapical radiolucency associated with the distal root.
- An additional (disto-lingual) canal.
- Moderately curved mesial root canals.
- One of the distal canals (disto-buccal) had a moderate curve in the apical-third.
- The other distal canal may be curved in the bucco-lingual direction.
Diagnosis and treatment planning
What is the diagnosis?
A diagnosis of chronic periapical periodontitis associated with an infected necrotic root canal system was reached for the 46.
The potential treatment options that should be discussed with the patient are:
- Root canal treatment (and a new post-endodontic cuspal coverage restoration if the caries or fracture lines were detected once the existing crown had been accessed).
- Leave alone.
Ideally, this tooth should be root treated so that it can be retained as a healthy functional tooth. Access to the tooth for treatment is adequate, and the radiograph reveals that the root canals appear to be patent, suggesting that the root canal treatment should be relatively straight forward to carry out. Extraction would also eliminate the patient’s symptoms, however, she would also lose an essential tooth, and the resulting unopposed maxillary first molar tooth would become non-functional and may over-erupt.
Although the patient could leave the tooth alone (i.e. have no treatment), this is not advisable as her existing symptoms will continue as will her occasional ‘flare ups’. In addition, she may eventually suffer from an acute apical abscess which, in severe cases, may result in pyrexia, malaise and even obstruction of her airway.
What was the most likely cause of this endodontic problem?
The cumulative effect of caries and cycles of subsequent restorative treatment most probably resulted in root canal system becoming necrotic and subsequently infected with bacteria.
Endodontic treatment was carried out in a single visit under local anaesthetic and rubber dam. The crown was accessed, no signs of microleakage, caries or fracture lines were detected. The root canals were mechanically prepared with hand stainless steel hand files and rotary nickel-titanium rotary files. Sodium hypochlorite was used as an irrigant and was regularly replenished as the active free chlorine ions (and therefore the antimicrobial effect) of the irrigant become depleted with time. The irrigant was also agitated with a size 20 ISO gutta point to ensure that the fresh irrigant circulated into the inaccessible parts of the root canal system. A working length radiograph was taken to confirm the zero readings obtained with an apex locator.