Endodontics
D3300-D3399

D3348Retreatment of Previous Root Canal Therapy - Molar

2026 Billing Guide ยท Last reviewed

Retreatment of a previously root canal-treated molar by removing the old filling material and re-cleaning and re-filling the canals.

What This Code Covers

D3348 covers the retreatment of a previously root canal-treated molar tooth. Molar retreatment is the most complex endodontic retreatment procedure due to the multiple canals (typically 3-4) and complex anatomy. The procedure involves removing all existing root canal filling material, locating any missed canals, re-cleaning and reshaping all canals, and placing new obturation material. The final restoration is billed separately.

Billing Guide

Bill this code when:

  • A molar that previously had root canal therapy requires retreatment
  • All existing filling material is removed from the molar canals
  • The canals are re-instrumented, disinfected, and re-obturated
  • The tooth has clinical or radiographic evidence of root canal failure

Do not bill this code when:

  • The tooth is anterior. Use D3346
  • The tooth is a premolar (bicuspid). Use D3347
  • This is the initial root canal, not a retreatment. Use D3330 for molar
  • Surgical retreatment (apicoectomy) is performed. Use D3410-D3427

Insurance and Denial Prevention

Key Payer Rules:

  • D3348 carries the highest retreatment fee due to molar complexity (3-4 canals)
  • Most payers cover molar retreatment when failure is documented radiographically
  • Some plans have a time limit (e.g., no retreatment within 2 years of original treatment)
  • A new crown may also be needed and should be billed separately if replaced

Common Denials and How to Respond:

  • Extraction recommended instead - Document the clinical and financial rationale for saving the tooth versus extraction and replacement with an implant or bridge.
  • Too soon after original treatment - Appeal with clinical evidence showing treatment failure regardless of timing. Periapical radiolucency, persistent symptoms, or new infection justify retreatment.
  • Missing pre-operative radiograph - Submit the radiograph showing the existing root canal fill with associated periapical pathology or symptoms documentation.

Claim Submission Checklist

0/6 complete
Tooth number
Pre-operative radiograph showing existing root canal fill and periapical pathology
Documentation of the original root canal (date, provider if known)
Clinical notes explaining the reason for retreatment
Post-operative radiograph showing new obturation in all canals
Associated restoration code billed separately

Frequently Asked Questions

Molar retreatment success rates are generally favorable when performed by an experienced provider. However, the decision depends on the tooth's restorability, the reason for failure, remaining tooth structure, and cost comparison with extraction and replacement. The provider and patient should discuss both options.

D3330 is the initial (first-time) root canal on a molar. D3348 is the retreatment of a molar that already has a root canal. Retreatment is more complex because existing filling material and possible obstructions must be removed before the canals can be re-treated.

If the existing crown must be removed and cannot be reused, a new crown can be billed. However, the crown frequency limitation applies. Some payers will cover the new crown; others may deny it if the previous crown was placed recently. Document why the existing crown could not be reused.

Keep This Handy

Save this D3348 reference for quick access during billing.

Codes commonly billed alongside or often confused with this procedure.