Patient: 65 year-old female with Hashimoto’s Disease and managed hypercholesterolemia

Chief Complaint: swelling on gums

Dental History: The patient reported a past history of root canal treatment (not recent) and a new crown on the maxillary left second bicuspid (less than a year). She started to notice some swelling associated with the area 3 weeks before the endodontic consultation.

Significant Findings (Tooth #13): a fluctuant buccal mass was noted opposite the said tooth which yielded slight discomfort when palpated. A periapical radiograph revealed a large periapical radiolucency and previous root canal treatment. The less radiopaque column of material in the coronal half of the root suggested a bonded fiber post. Clinical tests demonstrated Class 1 mobility, moderate percussion sensitivity, and periodontal findings within normal limits.

Pulp and Periradicular Diagnosis: Previous root filling with a nonmetal post, Acute Periradicular Periodontitis (Tooth #13)

Treatment Prognosis: Good (Tooth #13)

Treatment Plan: Post removal and nonsurgical endodontic retreatment (Tooth #13)

Special Considerations of Performed Treatment: Surgical endodontic retreatment is a popular option for failing recurrent root canal disease when the nonsurgical approach presents as challenging. It is well established that surgical retreatment has a lower success rate if definitive internal debridement is not performed. I behooves the clinician to learn advanced dismantling skill sets with the aid of the microscope rather than pick the less successful yet convenient and easier surgical option.

In this case, the patient and referring dentist were concerned a new crown had been placed and that nonsurgical access and dismantling through the crown would compromise the new restoration and potentially render the tooth non-restorable.

The author has developed a “penetration and staging technique” of post removal (see PDL case submission dated January 1, 2014, “Post Removal Sequence Described”:

http://www.puredentallearning.com/case-studies/case-62-september-2012-post-removal-technique-raw-image-series/?topic=all-by-date

Most posts can be removed atraumatically with minimal additional root dentin removal. A crown will not dislodge which is properly designed and cemented on a minimally adequate circumferential ferrule (AAE guidelines at least 2mm ideal and 1mm minimally adequate).

The post was removed uneventfully, noting a missed second (buccal) canal which was the likely etiology of failure although it joined the treated lingual canal. If the more convenient surgical approach had been chosen, the missed canal would have been uncleaned with a large volume of remaining sepsis, likely to percolate through any additional root portals of exit (POE) probably leading to another treatment failure.
After complete cleaning and shaping, both root canal systems were filled with calcium hydroxide and the access temporarily sealed with Cavit (no spacer).

At the end of one month, the temporary was removed, and the apical half of the root canal preparation was filled with MTA (mineral trioxide aggregate) due to the large irregular apical opening. A DT Light Post was luted with Luxcore bonded with Photobond and a Filtek esthetic surface placed. The crown remained intact without loosening throughout treatment.

Recall: The patient was recalled 17 months after treatment without symptoms or clinical signs of disease. A recall periapical radiographed demonstrated the absence of any periapical radiolucency and suggested complete osseous regeneration. A 5 year recall was scheduled at which time a CBCT scan will be performed to validate osseous regeneration in three dimensions.

Key Learning Points:

1. Nonsurgical endodontic retreatment is more predictable than surgical retreatment especially if a canal had been missed.

2. Posts can be atraumatically removed without removing additional dentin or loosening a properly designed and cemented crown.

3. Radiographs should be taken before the replacement of any crown.