For Referring Dentists

Refer a patient with a failed root canal

The "failed RCT" referral spans three different downstream treatment paths — non-surgical retreatment, microsurgical apicoectomy, or extraction with site preservation. This guide is the decision framework, success-rate evidence, and report-back protocol we use to triage which one the patient actually needs.

Medically reviewed by Dr. Jason Kung, DDS, MS · Specialist Endodontist · UCLA DDS · OHSU MS · May 23, 2026

Submit a referral Call (669) 234-2354

When to refer

Persistent or new apical radiolucency on a tooth treated more than 12 months ago, with or without symptoms.
Sinus tract or recurrent swelling traceable to a previously root-canal-treated tooth.
Symptomatic pain on biting, percussion, or palpation on a previously treated tooth that the patient describes as "never fully right."
Coronal leakage from a failed restoration, with re-contamination of the canal system suspected.
Apparent missed canal on a 2D periapical, particularly on a maxillary first molar where MB2 anatomy was not addressed.
Post and core in place but apical pathology persists — decision needed between disassembly retreatment vs. apicoectomy.

Decision framework — which path the patient needs

Non-surgical retreatment first when feasible

When the failure is plausibly due to coronal leakage, missed anatomy, or inadequate disinfection, and the restoration can be safely disassembled, non-surgical retreatment under the microscope is the first choice. Reported success rates for orthograde retreatment cluster around 77–85% in modern microscope-based studies (Sabeti et al., J Endod 2024 systematic review).

Endodontic microsurgery when retreatment is blocked or has already failed

Indicated when a tall cast post, screw-retained restoration, or extensive coronal restoration makes orthograde access prohibitively risky, or when prior retreatment has been performed and failed. Modern microsurgical apicoectomy with bioceramic root-end filling has published success rates around 91–94% (Setzer et al., 2010 meta-analysis).

Extraction with site preservation when prognosis is unfavorable

When CBCT or surgical exploration confirms a vertical root fracture, severe perforation, or extensive resorptive defect, we recommend extraction and refer the patient back to you for implant planning. We do not recommend treatment we cannot stand behind.

What you get back

Diagnostic CBCT review with the specific failure mechanism identified: missed canal, coronal leakage, periapical infection, fracture, perforation, or extra-canal anatomy.
Treatment recommendation aligned with AAE Treatment Options for the Compromised Tooth (2014): non-surgical retreatment, microsurgical apicoectomy, or extraction with site preservation.
Same-day written report and annotated CBCT slices to your office; direct phone call within 24 hours when the recommendation affects restorative planning.
When extraction is recommended, prognosis is communicated to the patient using the same favorable/questionable/unfavorable framework so the conversation continues seamlessly in your office.

Ready to refer?

Online referral form Call (669) 234-2354