Why Am I Being Charged for X-Rays? Dental X-Ray Billing Codes Explained

You've been going to the same dentist for years. You went in for your twice-a-year cleaning. You didn't ask for X-rays. But your bill has an X-ray charge on it — and your insurance only covered part of it.

What happened?

Here's a breakdown of the most common dental X-ray billing codes, how insurance handles each one, and how to determine whether you were charged correctly.

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The Most Common Dental X-Ray Codes

D0120 vs. D0150 — The Exam (Not an X-Ray, But Related)

Before we get into X-rays: you'll almost always see an exam code alongside any X-ray charges.

• D0120 — Periodic oral evaluation (your regular check-up with an established patient)
• D0150 — Comprehensive oral evaluation (used for new patients or after a significant period away)

These are diagnostic codes, not X-ray codes — but insurance often bundles them together when applying frequency limitations. Some plans won't pay for both an exam and certain X-rays on the same date.

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D0272 — Bitewing X-Rays (2 images)

D0274 — Bitewing X-Rays (4 images)

Bitewings are the small X-rays that show the back teeth from the side — the kind where they put that little card in your mouth and ask you to bite down. They show the surfaces between teeth and early cavity detection between molars.

D0274 (4 bitewings) is the most common code for an adult. It covers both sides of the upper and lower back teeth.

Insurance frequency limit: Most plans cover bitewings once every 12 months (some plans allow it every 6 months). If you had bitewings taken within the lookback window — even at a different dentist — the new claim may be denied or paid at a reduced rate.

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D0210 — Full-Mouth Series (FMX)

A full-mouth series is a comprehensive set of X-rays — usually 18–21 individual images — that shows every tooth from root to crown. It's used for a thorough diagnostic picture, often at a new patient exam or when significant dental issues are being worked up.

This is an expensive code. D0210 can run $150–$250+ in the dentist's fee schedule.

Insurance frequency limit: Most plans cover a full-mouth series every 3–5 years only. If you had one done recently, the next one may not be covered until the lookback window resets. This is one of the most common sources of surprise X-ray bills.

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D0330 — Panoramic Radiographic Image (Panorex)

The panoramic X-ray is the one where you stand in front of a machine that rotates around your head. It produces a single wide-angle image showing all the teeth, jawbones, and surrounding structures in one picture.

Used for: new patient intake, wisdom tooth evaluation, implant planning, orthodontic workup.

Insurance coverage: Usually covered once every 3–5 years, similar to the full-mouth series. Some plans only cover one or the other — not both D0210 and D0330 in the same year.

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D0220 — Periapical X-Ray (Single Tooth)

A periapical (PA) X-ray shows one specific tooth from crown to root tip. It's used when a dentist wants to look at a specific area of concern — an abscess, a fracture, post-treatment healing.

Insurance coverage: Generally covered as needed for clinical purposes, though plans may limit the number per year. You'll see D0220 on bills when a problem tooth is being investigated.

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Why Did I Get X-Rays I Didn't Ask For?

Most dentists have established X-ray schedules based on clinical guidelines. For a low-risk adult patient, the American Dental Association generally recommends bitewing X-rays every 12–24 months and a full-mouth series every 3–5 years.

Your dentist decides when to take X-rays based on your clinical status — not just when your insurance will pay for them. If they judged that it was clinically appropriate to take X-rays at your visit, they'll typically do so regardless of your insurance coverage.

The problem: Patients often aren't told upfront that their insurance won't cover the X-rays at that frequency — and they end up paying out of pocket.

What you can do: Before any X-rays are taken, ask the front desk: "Will my insurance cover these? When were the last X-rays billed to my plan?" Most billing software can check this in seconds.

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Bundling Issues: When Insurance Won't Pay for Separate Codes

Some dental insurance plans consider certain X-rays to be "included" in other procedures and won't pay for them separately. Common examples:

• Some plans bundle D0274 bitewings into a comprehensive exam (D0150) and won't pay both separately on the same date
• Some plans consider D0210 (FMX) and D0330 (panorex) to be equivalent and will only pay for one in a given year

If your EOB shows an X-ray code as denied with the reason "inclusive of another procedure" or "paid as part of exam," this is what happened.

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When to Question an X-Ray Charge

It's reasonable to ask your dental office:

• What clinical reason prompted these X-rays? (You have a right to know)
• When were the last X-rays taken? Is this within my plan's frequency limit?
• Did you check my insurance eligibility before taking them?

If X-rays were taken sooner than your plan's frequency limit allows, and you weren't warned that insurance wouldn't cover them, it's worth asking whether the office will write off the balance. Not every office will — but it's a reasonable conversation, especially with a long-term patient.

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Confused by the X-Ray Charges on Your Bill?

Diagnostic billing can be one of the more opaque parts of a dental bill — especially when X-rays show up unexpectedly. If you're trying to figure out whether you were billed correctly for D0274, D0210, D0330, or any other diagnostic code, MyBillRX can help. Upload your bill at mybillrx.com and get a plain-English breakdown of what each charge means and whether your insurance handled it correctly.