D9974 is the CDT code for whitening a root-canal-treated tooth from the inside by sealing a bleaching agent in its crown, reported per tooth.
- When to use: A tooth darkened after its pulp died and was treated, so the stain sits in internal dentin that external gel cannot reach.
- When not to use: External bleaching of one tooth is D9973, arch whitening is D9972 or D9975, and the root canal keeps its own code, such as D3310 on an anterior tooth.
- Billing note: Many plans sweep internal bleaching into the cosmetic exclusion, so verify D9974 by code and submit with the endo and trauma history.
What D9974 covers
D9974 reports whitening a non-vital, root-canal-treated tooth from the inside. The dentist reopens the access cavity in the crown, confirms or places a protective barrier over the root canal filling, seals a bleaching agent into the pulp chamber, and closes the tooth with a temporary. The agent works from inside the dentin (the walking bleach) and is exchanged or removed at follow-up visits until the shade is reached, after which the access is restored permanently.
The typical case is an anterior tooth that turned grey or brown after the pulp died and was treated. The stain is in the internal dentin, which tray gel and chairside arch whitening cannot reach. That is why this code exists separately from the external bleaching codes.
The unit is per tooth. The claim line carries the tooth number, and two darkened endo-treated teeth are two lines.
What it does not cover
- External bleaching of the same tooth. Agent on the outer enamel surface is D9973, even for a single discolored tooth. The axis is inside vs outside, not how many teeth.
- Cosmetic whitening of an arch. Chairside is D9972; dispensed trays are D9975.
- The endodontic treatment itself. The root canal that preceded the discoloration was billed on its own code (D3310 for an anterior tooth, D3320 or D3330 further back), by your office or another, and D9974 does not reopen that fee.
- The definitive restoration afterward. If the case finishes with more than closure of the access, such as a veneer (D2962) or a crown, that work is its own code and its own, often stronger, coverage conversation.
The coverage argument, and where it stops
Internal bleaching has the strongest coverage case among the whitening codes. The tooth has a documented history: trauma or decay killed the pulp, endodontic treatment followed, and discoloration is a known sequela. Framed that way, D9974 repairs damage, and some plans will consider it, occasionally under trauma provisions and occasionally as a covered adjunctive service.
Plan language is where the argument stops. A contract that excludes “bleaching, whitening, or lightening of teeth” by category usually does not carve out the internal variant, and no narrative rewrites an exclusion. Do not promise the patient coverage because the tooth “isn’t cosmetic.” Instead:
- Verify the plan and ask specifically whether D9974 falls under the cosmetic exclusion.
- If coverage is possible, submit with the full history: date of trauma if there was one, date of endodontic completion, and pre-treatment photos or shade documentation.
- If the exclusion is categorical, or the plan’s answer is anything short of confirmed coverage, collect at the time of service and give the patient a superbill for FSA/HSA purposes. Administrators split on whitening, and a documented medical cause helps the patient’s case with them too.
Documentation that carries the case
A D9974 claim or FSA superbill should let a stranger reconstruct the tooth’s history:
- Why the tooth is non-vital: trauma date and mechanism, or the caries and endo history, with the root canal completion date.
- Shade evidence: photos or shade-guide readings of the treated tooth against its neighbors, before and after.
- The barrier and material: what was placed over the root filling, what agent was sealed in, and the date of each exchange visit.
- The endpoint: final shade and how the access was permanently restored.
If the case later escalates to a veneer or crown because bleaching alone could not deliver the esthetics, the documented bleaching attempt supports the medical-necessity case on the restorative claim.
Sessions, retreatment, and relapse
Walking bleach is iterative: agent in, a week or two, evaluate, exchange, repeat, commonly across two to four visits. The code does not say per visit, and the safe default is one fee per tooth per course, with every visit charted.
Internal bleaching results can regress, and shade relapse years later raises the question of a second course, which is a new billing event. Whether any carrier will pay the code twice on the same tooth is plan-dependent; on a patient-pay basis it is simply a fee conversation.
What to get right in your PMS
- Tooth number on the line, every time. A line without the number pends.
- Show the endo history next to the bleaching entry. The root canal history is the claim’s best evidence and the first thing a reviewer asks for.
FAQs
- What is the dental code for internal bleaching?
- D9974, reported per tooth. It covers placing a bleaching agent inside the crown of a non-vital, root-canal-treated tooth, the walking bleach approach. External bleaching of a single tooth is D9973, and arch-level whitening is D9972 (in office) or D9975 (take-home trays).
- Can D9974 be billed on a vital tooth?
- No. The code is specific to a non-vital tooth. Opening the crown to place an internal agent presumes completed endodontic treatment with the canal sealed below. Discoloration on a vital tooth goes to external options: D9973 for one tooth, or the arch codes for a cosmetic case.
- Does insurance cover internal bleaching?
- Sometimes, and more plausibly than external whitening. When the discoloration followed documented trauma or endodontic treatment, some plans will treat D9974 as part of restoring the tooth rather than as elective cosmetics. Many plans still include it in the bleaching exclusion. Verify the specific plan, submit with the endo and trauma history, and collect from the patient if the exclusion is categorical.
- The bleaching took three visits to change agent. Do I bill D9974 three times?
- Usually no. The code is per tooth, not per visit, and most offices treat the multi-visit walking-bleach course as one fee per tooth. Whether a carrier recognizes repeat submissions on the same tooth is plan-dependent, and repeat lines within one course invite denial as duplicate. Chart every visit and post the fee once unless you have plan-specific guidance otherwise.
Related codes
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CDT codes are maintained by the American Dental Association. This page is an editorial billing guide, not the official ADA code descriptor. Verify current coverage policies with each carrier before submitting claims.