Claims · Updated 2026-09-08 · 5 min read

Why weren't the x-rays taken during my root canal paid separately?

Working-length and final-fill films are part of the endodontic procedure at MetLife Aetna United Concordia Delta and Guardian. The patient is not billed.

The films taken during root canal treatment — the working-length shots and the final-fill check — are part of the endodontic procedure in every carrier document that addresses them, so they are denied when billed as separate periapicals (D0220/D0230) on the same date as the root canal. Aetna states that "D0230 is part of the endodontic therapy". United Concordia denies the working-length and final-fill images as integral. Delta calls them a component of the complete treatment procedure. The diagnostic film taken before treatment starts is a different thing and is generally payable. As of September 2026, MetLife bundled 188 of 2,909 additional-periapical lines (6.5%) as included in another procedure. Where the dentist is in network the bundled film is written off, not billed to the patient; an out-of-network dentist may charge for it separately.

What we measured

Every remittance line for those codes at that carrier, all dates, measured on 8 September 2026 across 37 practices and more than 170 payers. This counts every bundling denial on the periapical codes, not only the films taken during endodontic treatment — a film bundled into a complete series or into a crown is in the same total. We do not publish a separate rate for endodontic films.

What the carriers' own policies say

MetLife's Preferred Dentist Program (PDP) Resource Manual names the whole set of things that ride inside the root canal:

"Root Canal Therapy: The following procedure(s) can't be billed as a separate charge to a participant when performed in conjunction with root canal therapy on the same tooth: Intra-operative treatment radiographic images (D0220/D0230), Pulp Testing (D0460), Sedative filling (D2940), Pulpotomy (D3220), Canal Preparation (D3950), Palliative Treatment (D9110) … rubber dam (D3910)."

Aetna's Specialty Dental Office Guide (network bulletin, July 2017), which applies to all Aetna Dental plans, draws the line between the diagnostic film and the treatment film:

"To align with the ADA nomenclature for endodontic therapy, periapical radiographic images D0230 will be denied when performed in conjunction with endodontic therapy on the same date of service. D0230 is part of the endodontic therapy. Diagnostic evaluation and images are not part of the endodontic therapy."

The United Concordia Dental PPO Clinical Policy (last updated May 2026) uses the clinical names:

"Denied as INTEGRAL when reported as part of endodontic treatment ('working length' and 'final fill' x-rays) and not diagnostic purposes, which includes any periapical radiograph image (D0230) reported by the same Dentist, on the same date as a Pulpotomy (D3220-D3222), Endodontic therapy (D3230-D3333)…"

Delta Dental's national processing policies, in the DeltaUSA Dentist Handbook, January 2026, under D0230:

"Routine working and final treatment radiographic images taken for endodontic therapy by the same dentist/dental office are considered a component of the complete treatment procedure and separate fees are not billable to the patient on the same date of service."

Guardian's DentalGuard Preferred Network Dentist Manual, November 2020 is the one that spells out which film survives:

"The diagnostic and working radiographs taken at the time of root canal treatment, other than the initial periapical, are considered inclusive of the root canal procedure."

Guardian's Colorado state appendix also applies a 14-day window: a film taken within 14 days of the root canal is inclusive of it. Liberty's National Clinical Criteria Guidelines and Practice Parameters, 2026 generalises past endodontics: "radiographs taken during a restorative, endodontic, or surgical procedure are considered part of the procedure and are not reimbursed separately."

Why it depends on the plan

The rule itself barely varies — six carriers say the same thing in six vocabularies. What varies is where the boundary sits. Aetna and Guardian both protect the initial diagnostic film. United Concordia scopes its denial to films reported "as part of endodontic treatment … and not diagnostic purposes", which makes the claim narrative decide. The Colorado appendix's 14-day rule reaches back beyond the date of service, so a film taken at the emergency visit a week earlier can be absorbed into the root canal billed later.

United Concordia also treats a film taken for restorative work the same way — a periapical billed on the same date as an inlay, onlay, crown or bridge is denied as integral when it was part of the restorative treatment rather than diagnosis.

What to do

• Bill the pre-treatment diagnostic film on the visit where the diagnosis was made, and describe it as diagnostic. That is the film the documents protect.
• Do not bill working-length or final-fill films at all. They are inside the endodontic fee at every carrier that has published a rule.
• Where Guardian's Colorado state appendix governs, check whether a film billed in the two weeks before the root canal will be absorbed into it before you promise the patient a separate benefit.
• Post the denial as a write-off on a participating claim — MetLife, Delta and United Concordia all state the patient may not be charged. An out-of-network dentist has made no such agreement and may charge separately.
• If a film was genuinely taken for a different tooth or a different problem on the same day, note the tooth number and the reason on the claim at submission.

Numbers last refreshed September 2026.

All articles · Kaylie