D3346 is the CDT code for endodontic retreatment of a previously treated anterior tooth. It applies when a prior root canal on an incisor or canine has failed and requires removal of the existing filling material, re-instrumentation, and re-obturation of the canal system. This is a distinct procedure from initial root canal therapy and requires separate clinical justification.
Last updated June 2026 ยท Reviewed by the PracticeAlpha billing team
Get help with D3346 claims →Radiographic evidence of persistent or new periapical lesion on a previously root-canal-treated anterior tooth. The lesion indicates that the initial treatment did not fully eliminate infection.
Tooth with a prior root canal remains symptomatic (pain, swelling, sinus tract) despite completed endodontic treatment. Clinical and radiographic evaluation supports retreatment rather than extraction or apicoectomy.
Radiograph shows the existing root canal fill is short, voids are present, or canal anatomy was missed during the original treatment. Retreatment is indicated to address the technical deficiency before it leads to further failure.
The most common coding error for retreatment cases. If a tooth has prior root canal therapy and you perform retreatment, the correct code is D3346, not D3310. Billing D3310 for a previously treated tooth misrepresents the procedure. Payers cross-check claim history. If records show prior RCT on that tooth and you bill D3310, expect a denial or audit request.
Retreatment requires clinical justification that the prior root canal failed. The pre-operative radiograph must show the existing root canal fill, and ideally periapical pathology or evidence of inadequate obturation. Clinical notes must document the signs and symptoms of failure. A note that says "patient needs retreatment" without clinical evidence will not support the claim.
Many plans require pre-auth for endodontic retreatment specifically. Retreatment is reviewed more closely than initial RCT because payers want to assess whether the procedure is appropriate versus extraction. Submit pre-auth with the radiograph showing prior RCT and the clinical narrative before starting treatment. Failure to obtain pre-auth is one of the top denial reasons for D3346.
Some dental plans impose waiting periods after initial root canal therapy before retreatment will be covered. Others exclude retreatment entirely, covering extraction and implant instead. Always verify the patient's specific plan benefits before scheduling. If retreatment is excluded, document the discussion with the patient so they can make an informed decision.
Must show the existing root canal fill on the anterior tooth, and ideally periapical pathology (widening of the PDL space, periapical lesion, or bone loss). This is the primary piece of evidence supporting retreatment over initial RCT.
Document specific signs and symptoms: persistent pain, swelling, sinus tract, sensitivity to percussion, or radiographic evidence of new or persistent periapical pathology. Be specific about what has changed or failed since the initial treatment.
Many payers require a written explanation of why retreatment is the appropriate treatment choice rather than extraction. Address restorability, strategic value of the tooth, and patient preference where relevant.
Records from the original root canal help document the history and support the retreatment decision. If the prior treatment was performed at another office, request those records or note in the chart that they were unavailable.
Confirming completed obturation after retreatment. The post-op x-ray documents the quality of the retreatment and is often required by payers to finalize reimbursement on major endodontic procedures.
Document the pre-auth number in the patient record and include it on the claim. If the plan required pre-auth and you did not obtain it, expect a denial. If the plan does not require pre-auth, note that you verified it does not.
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Get a free AR analysisD3346 is the CDT code for endodontic retreatment of a previously treated anterior tooth. It covers removal of existing root canal filling material, re-instrumentation, and re-obturation of the canal system on an anterior tooth (incisors and canines) when the original root canal therapy has failed.
D3310 is initial root canal therapy on an anterior tooth with no prior endodontic treatment. D3346 is retreatment of an anterior tooth that already had a root canal. If the tooth has prior RCT, use D3346. Billing D3310 for a retreatment case is a coding error that triggers denials and audit exposure.
D3346 is endodontic retreatment for anterior teeth (incisors and canines). D3348 is endodontic retreatment for molar teeth. Premolar retreatment uses D3347. The tooth type determines the code. Always confirm the tooth number before selecting the retreatment code.
Common reasons include billing D3310 instead of D3346 for a retreatment case, insufficient documentation of endodontic failure, missing pre-authorization, plan-specific exclusions for retreatment, and frequency limitations. A written narrative explaining clinical justification significantly reduces denial rates.
Many dental plans require pre-authorization for endodontic retreatment. Submit pre-auth with the pre-operative radiograph showing prior RCT and a narrative documenting the clinical basis for retreatment. Check the patient's specific plan before scheduling treatment.
Required documentation includes a pre-operative periapical radiograph showing the existing root canal fill and any periapical pathology, clinical notes documenting signs of endodontic failure, a narrative justifying retreatment over extraction, and a post-operative radiograph confirming completed obturation. Prior treatment records should be included or their absence noted.
Search all CDT codes in our dental coding guide.