A root canal retreatment involving a crown and a post removal alowed for this painful tooth to be preserved

      An endodontist case report. Microendodontics case study number: 505026

Twenty five years old patient presenting with an abscessed maxillary molar. Diagnosis: Persisting disease after root canal treatment. Etiology: untreated second mesio vestibular root canal (MB2).

Two appointments were required to preserve that tooth:


First appointment: Crown and post removals plus root canal filling retrieval, MB2 location and calcium hydroxide insertion as a medicament. 




Second appointment: Calcium hydroxide removal, irrigation, drying, final canal obturation gutta percha and Pulp Canal Sealer. Provisional filling material: Cavit.


Abutment is now symptom free and it is now all set for a casted post and permanent crown replacement.




A 6 months follow up dental Xray film shows an impressive  regeneration of periradicular tissues. Compared to its initial size, apical lesion on mesio vestibular root shrunk up to 80%. Tooth is asymptomatic and functional.



A complex root canal retreatment does not have to mean extraction and replacement by a dental implant. A research study by Farzaneh et al. on treatment outcome in endodontic found an orthograde root canal retreatment success rate of 93% . (Farzaneh M., Abitbol S., Friedman S. Treatment outcome in endodontics: The Toronto Study. Phases I and II: Orthograde retreatment. J Endod 2004; 30(9):627-633)


To save or not to save? that was the question. A seven years post endodontic treatment outcome follow up

Patient was told seven years ago to remove lower right premolar and replace this tooth by an implant supported crown. Lack of periradicular tissues implied a guided tissue regeneration wich, in turn implied a bone curetage close to the mental foramen. Estimated health risk: A possible permanent nerve paresthesia caused by a curetage or by an implant surgery close to the mental foramen on a patient with a narrow crestal mandibular bone. A possible failure of guided tissue regeneration wich in turn, would impair implant osseointegration (or simply make the implant surgery impossible). Clinical examination revealed a mobility level of 2 and a sinus tract. Our findings on radiographic appearance: a large but a localised bony defect and a tooth that needed a root canal retreatment. Our suggestion to the patient: To put aside the implant surgery and to invest in a root canal retreatment with a few Ca(OH)2 replacements. The patient had to be patient (and faithful) for a few months in order to monitor progressive periradicular tissue healing. Results: Per and post operative control X ray films show a progressive, then complete healing of periradicular bone tissue. In this case, root canal retreatment proved to be a safe predictable way of saving that tooth at half the cost of an agressive implant surgery. Now, 7 years later, the tooth has it’s own casted post, a PFM crown and it’s mobility level came back to zero. And above all, patient is now completely safe from any paresthesia risk.