D3346 Dental Code: Anterior Root Canal Retreatment

What D3346 covers

D3346 reports nonsurgical retreatment of a permanent anterior tooth, an incisor or canine. Carriers typically validate it against teeth 6 through 11 and 22 through 27. The tooth had a completed root canal that failed, and the dentist reopens it through the crown, removes the existing filling material, re-cleans and reshapes the canals, and refills them.

Three things are included in the code and are not separate lines:

• Removing the old fill and anything on top of it. Reaching the canal usually means removing a post, pins, and the existing obturation. HDS’s endodontic guidelines state those component procedures are not separately billable to the patient, and carriers commonly treat them the same way.
• Every visit. Anterior retreatments often run two appointments with an interim medicament. The code reports the whole course once, on the date the canals are obturated.
• Intraoperative films. Working-length images are part of the procedure, and HDS says interim working films should not be submitted for payment. Diagnostic radiographs taken to evaluate the tooth bill on their own date of service. Send the final post-op periapical as the claim’s attachment, but expect most carriers to treat it as part of the procedure rather than a separately payable film.

The final restoration is not included. An anterior tooth coming out of retreatment may need only a composite in the access, or a buildup (D2950) and a crown if it was already heavily restored. Those bill on their own dates.

Retreatment or initial therapy: what the film has to show

Tooth type sets which retreatment code you use; treatment history, read off the pre-op radiograph, sets whether you are in the retreatment family at all. Obturation material in the canal means D3346. Empty canals mean a first root canal, D3310.

The trap on anterior teeth is the middle case. A traumatized incisor is often opened elsewhere years earlier, medicated, temporized, and never finished. It has an access opening and a temporary but no fill, so there is no previous root canal to retreat. Completing it now is D3310, even if the patient says they already had a root canal on it.

An anterior tooth treated years ago with apexification (D3351 through D3353) on an immature root did receive a completed root canal filling, so redoing it is retreatment. Carriers holding the apexification history sometimes ask for the narrative anyway, so send it with the claim.

Which code: the family around D3346

Retreatment splits by tooth position the same way initial therapy does:

• D3346 anterior, incisors and canines.
• D3347 premolar.
• D3348 molar.

The initial-therapy equivalents are D3310, D3320, and D3330. Position drives the code, not canal count or difficulty: a mandibular incisor with two canals and a calcified apex is still D3346. Label all six codes in your PMS pick list by position and by history; a list that reads “root canal anterior” twice invites the wrong pick. The root canal dental codes guide compares the retreatment windows carriers publish.

Two neighboring procedures are confused with anterior retreatment more often than with the molar version, because anterior roots are the easiest to reach surgically:

• D3410, apicoectomy on an anterior tooth. A surgical root-end procedure through the gum and bone, where D3346 is nonsurgical, through the crown. A case can involve both at separate visits, as separate codes. Retrograde filling material placed during the surgery is D3430, per root, and is not part of the apicoectomy code.
• D3331, treatment of root canal obstruction by nonsurgical access. Reports opening a pathway through a canal blocked by a separated file, a broken post, or heavy calcification, as the alternative to surgery. If the canal was retreated and refilled, the procedure is D3346. D3331 is for the case where establishing the pathway is the procedure.

When to bill D3346

1. Confirm the tooth position. Incisor or canine. Premolars are D3347 and molars D3348, however the case behaved clinically.
2. Confirm existing fill on the pre-op film. No obturation material, no retreatment code.
3. Find the date of the original root canal and who did it. This decides whether the claim pays at all. Pull it from the ledger if your office treated the tooth, and ask the patient if another practice did.
4. Check the plan’s elapsed-time rule before submitting. Ask how long it has been since the original root canal, and whether the plan treats a same-office redo differently from a different-office one. If the original is inside the window, decide up front whether the claim goes out, gets predetermined, or gets adjusted off.
5. Bill on the obturation date. One line, one date of service, not one per visit and not on the access appointment.
6. Bill the restoration separately. Buildup and crown, if needed, go on their own dates.

Coverage and how carriers treat it

Most plans cover retreatment at the same tier as initial endodontics. Timing and provider decide the claim.

The elapsed-time window. Twenty-four months after the original root canal is the common number. A Delta Dental PPO plan document published for one employer group states the retreatment benefit as once per tooth after 24 months from the initial treatment. Some plans run longer, so verify against the contract.

Who performed the original treatment. HDS treats a retreatment by the same dentist or office within 24 months as part of the original procedure, so the practice cannot bill the patient for it. HDS also denies benefits when a different dentist does the retreatment inside the same 24 months, with exceptional circumstances reviewed case by case. Other carriers pay a different-office retreatment inside the window because the second practice was never paid for the first treatment. Two published carrier rules give opposite answers, so verify the plan.

Lifetime limits. Plans commonly cap both initial therapy and retreatment at once per tooth per lifetime. A DeltaCare USA copayment schedule published for State of Maryland employees lists D3346 that way, at an enrollee copay of $198 against $108 for initial anterior therapy under D3310. The lifetime cap is why a retreatment miscoded as D3310 tends to deny as a duplicate rather than underpay.

Prognosis review. Some plans read anterior retreatment on a tooth with a fracture, a perforation, or heavy resorption as not restorable. Predetermination is worth it on borderline teeth, especially where the alternative is extraction and an implant.

Documentation that supports the claim

Retreatment claims need more attachments than initial therapy. HDS lists the first three items below as submission requirements on D3346 through D3348, and most carriers want the same set:

• Pre-op periapical showing the existing canal filling, plus what failed: an apical radiolucency, a short or voided fill, a missed canal, a post space, coronal leakage.
• Post-op periapical showing the completed retreatment. Label both films as pre-op and post-op.
• A narrative giving the diagnosis and why the first treatment failed. A pulpal and apical diagnosis in standard terms carries more weight than a description of symptoms.
• The date of the original root canal and the treating office. State plainly when another practice did the original; on plans with a same-office bundling rule, that is what takes the case out of it.

Attach the films to the claim itself, not just the patient chart. Many systems store images at the patient level, and the clearinghouse needs them linked to the claim.

In the chart, record the material removed and any post or separated instrument taken out, the canals located and retreated including any the first treatment missed, working lengths, the obturation material, and the planned final restoration.

For how the tooth number, the date of service, and the remarks field are filled in on the claim itself, see the ADA dental claim form guide.