Here's a tooth that had endodontic treatment over 10 years ago. While the clinician had difficulty finding all the canals, the tooth has been functional for quite some time. A large furcal defect raises suspicion of a root fracture or perforation.
DX: Prior RCT w/ Symptomatic Apical Periodontitis.
There are many who would consider this hopeless and recommend extraction.
Let us consider the cause of this treatment failure:
1. Missed Canals
2. Furcal Perforation or Root Fracture?
Can these issues be addressed to preserve the natural tooth?
In my consultation with the patient, I explain these issues and that endodontic re-treatment may be able to save the tooth (as long as the root is not fractured). I also explain the alternative option of extraction.
Finding missing canals is a simple solution.
A perforated root can be repaired with guarded prognosis.
A fractured root will require extraction.
I tell the patient the only way to know for sure is to open the tooth and investigate. Considering the nice crown on the tooth, the cost of attempting to save the tooth is minimal, compared to the cost of removing and replacing. In this case the patient elected re-treatment.
Upon access, 2 additional canals are located and instrumented. A furcal perforation is also identified. No root fractures are found.
Re-treatment is complete. Canals obturated with gutta percha and furcal perforation repaired with MTA. Glass ionomer base is placed over MTA.