D4266 Dental Code: How to Bill Guided Tissue Regeneration on Natural Teeth

The D4266 dental code reports guided tissue regeneration (GTR) at a natural tooth using a resorbable barrier membrane. You bill it once per defect site, on its own claim line, with a tooth number. D4266 pays for the membrane and nothing else, so flap access, grafts, and biologics each need a separate line.

Money leaks at the edges of this code. Some offices report D4266 at an extraction socket or an implant, where a different code applies. Others fold the membrane into the graft line and never bill it. Payers answer with denials, downgrades, and sometimes recoupment months later.

This guide comes from the billing team at iDental Billing. It covers the code's exact scope, the look-alike GTR codes, site counting, current rules from Cigna, UnitedHealthcare, and Aetna, the documentation reviewers check, and how to appeal a denial.

D4266 at a Glance

What Is the D4266 Dental Code?

The D4266 dental code is the CDT code for guided tissue regeneration on a natural tooth with a resorbable barrier, reported per site. In its guide to reporting wound dressings, the ADA says the procedure "can be used for periodontal defects around natural teeth." It pays for placing the membrane only.

You'll see it written as 4266, ADA code D4266, or CDT D4266 on fee schedules and EOBs. All three mean the same line. A membrane keeps gum tissue from growing down into the bony defect while bone and periodontal ligament fill in. UnitedHealthcare's GTR policy names collagen and synthetic aliphatic polyesters as resorbable options.

D4266 sits in the Periodontics category, under surgical services. CDT codes carry no specialty restriction, so a general dentist can report it too. The ADA's 2026 graft guide says the related regenerative graft procedures may be reported by any dentist authorized by the state practice act. Our guide to CDT code categories shows how the sections fit together.

Is D4266 a Bone Graft?

No. D4266 is the barrier membrane, and the graft material under it is a separate procedure. At a natural tooth, the graft is D4263 for the first site in a quadrant and D4264 for each additional site. The ADA's 2026 graft material guide states that both graft codes exclude barrier membrane placement.

Those graft codes have a site limit, too. The same ADA guide says D4263 and D4264 are "not to be reported for an edentulous space or an extraction site." Once the tooth comes out, both the graft code and the membrane code change, and the comparison section below shows where each one goes.

What D4266 Doesn't Include, and What You Bill Separately

Read the full D4266 dental code descriptor and you'll find a list of exclusions: flap entry and closure, wound debridement, osseous contouring, bone replacement grafts, and biologic materials. If the surgeon performs any of those, each one goes on its own claim line with its own code.

A graft and a membrane at the same site means two lines, even when they go in a minute apart. If someone asks for the ADA code for membrane with bone graft, give them two: D4263 or D4264 for the graft, and D4266 for the barrier. Folding both into one line hands the payer a free membrane.

Plans differ on a flap and a membrane billed for the same tooth and date, so read the processing policy before you quote the patient. Load an office fee for every code in that table, too. A line that goes out at $0 can't pay more than $0, and the gap usually shows up only on the EOB.

If membrane lines keep going missing on your perio claims, our dental billing services team can review the fee schedule and code setup with you.

PRF or Enamel Matrix Derivative: D4265 or D7921?

Enamel matrix derivative goes on D4265. PRF and PRP go on D7921, collection and application of autologous blood concentrate product. UnitedHealthcare's Biologic Materials policy (DCP047.05, effective May 1, 2026) handles them as separate codes. It lists enamel matrix derivative and bioactive glass as biologics that may be indicated for regeneration.

That same UHC policy says autologous blood concentrate products "are not indicated," citing insufficient evidence. Report PRF on D7921 anyway when the surgeon uses it, and tell the patient up front that a UHC plan is likely to leave that line unpaid. Moving PRF to D4265 to get it paid misreports the procedure.

Which GTR Code Fits the Site? D4266 vs D4267, D6106, D7956, and D3432

CDT splits guided tissue regeneration into seven placement codes, and the D4266 dental code is only one of them. Two questions decide the code: where's the defect, and does the membrane resorb? The table follows the code set in the VA's DNT-0005 clinical decision template, effective July 1, 2026.

Source: VA DNT-0005 (July 1, 2026) and UnitedHealthcare DCP045.10 code lists. Removal of a non-resorbable barrier is D4286.

Check the GTR pick-list in your practice software. If it offers only D4266 and D4267, an assistant charting a socket or an implant membrane has nothing correct to choose. Add all seven placement codes to the surgical templates so the code follows the site.

D4266 vs D4267: Resorbable or Non-Resorbable

Barrier material is the only difference. D4266 covers a membrane the body breaks down on its own. D4267 covers a non-resorbable membrane, such as expanded polytetrafluoroethylene (e-PTFE), that a second procedure removes. Both codes are per site, and both are limited to natural teeth.

Payers split on the removal visit. Cigna's 2026 PPO guideline treats removal of a non-resorbable barrier (D4286) as part of the D4267 service, so it won't pay separately. Other plans may, so check before the second appointment. Peri-implant membranes never go on D4267; they belong on D6106 or D6107.

D4266 vs D7956: Extraction Sockets and Edentulous Ridges

Once the tooth is out, the site isn't a natural tooth anymore. A membrane over a fresh socket or an edentulous ridge is D7956 when it resorbs and D7957 when it doesn't. That's the ADA code for membrane after extraction, and it sits in the oral surgery section of CDT, far from D4266.

Cigna's PPO guideline spells out the D4266 side: GTR isn't allowable "when performed at the same site as a tooth removal or where there is no natural tooth present." Ridge preservation grafts follow the same split. D7953 covers the graft, and the ADA's 2026 graft guide says to report any membrane used with it separately.

A socket graft claim on tooth #19 looks like this (example only):

• D7210 surgical extraction, tooth #19
• D7953, bone replacement graft for ridge preservation, tooth #19
• D7956, resorbable membrane in an edentulous area, tooth #19

Already sent D4266 for a socket? Send a corrected claim with D7956 before the payer finds it, and keep the surgical note that supports the change. A paid D4266 at an extraction site is an easy target for post-payment review and recoupment, sometimes months after the payment posts.

D4266 vs D6106: Membranes at Implants

Implant membranes bill per implant: D6106 for resorbable and D6107 for non-resorbable. Grafts there use D6104 at the time of implant placement and D6103 for repair of a peri-implant defect. Per the ADA graft guide, the membrane is reported separately from both. D6103 and D6104 are graft codes, never membrane codes.

A mixed case still splits by site. Picture a membrane at implant #19 and another at a separate defect on natural tooth #18: that's D6106 for #19 and D4266 for #18. Cigna's guideline also bars GTR at the site of an existing implant or at the same site and date as implant placement.

D4266 vs D7922: Membrane or Hemostatic Dressing?

Collagen products blur this line. The ADA's wound dressing guide answers the question head-on: Gelfoam placed in an extraction site is a dressing reported with D7922, and D4266 "is used to report a completely different procedure."

Code by what the collagen is doing. Collagen shaped as a barrier over a periodontal defect at a natural tooth is D4266. A collagen plug packed into a socket to control bleeding or hold the clot is D7922, reported per site. If both go in, the ADA guide says to report each one.

Our dental extraction codes guide shows how D7922 pairs with each extraction code, including the surgical ones.

How to Count Sites and Code a Full Regenerative Surgery

Site counting decides how many D4266 dental code lines go out, and each line carries its own fee. Count too few and a membrane goes unpaid. Overcount, and you've billed a site the chart can't defend.

What "Per Site" Means for D4266

CDT defines a site as a single area, position, or locus. For bony defects, two contiguous teeth with adjacent but separate defects have two sites. A defect that communicates across the interproximal space between them counts as one site. D4266 has no "each additional site" code, so every site repeats D4266 on a new line.

Say the surgeon treats a 3-wall defect on the distal of #30 and a separate 2-wall defect on the distal of #31, each with its own membrane. That's two D4266 lines. If one defect runs across the contact between #30 and #31 and a single membrane covers it, you bill one line.

Worked Example: Osseous Surgery, Graft, Biologic, and Two Membranes

Example only. Mandibular right quadrant, osseous surgery from #28 to #31, regenerative work at separate defects on #30 and #31, and enamel matrix derivative at #30.

Not every payer will pay all six lines. Cigna's 2026 PPO guideline doesn't allow D4265 when other regrowth treatments happen at the same site on the same date, so line 4 is at risk on a Cigna PPO plan.

Cigna also says the patient isn't responsible for that line, which matters for your estimate.

Claim Fields for Each D4266 Line

Enter the tooth number in item 27 of the 2024 ADA claim form on every D4266 line. The ADA's Dental Claim Data Recommendation marks D4266 for tooth number and recommends against reporting an area of the oral cavity, so item 25 stays blank on these lines.

Diagnosis codes go in item 34a, with the qualifier "AB" in item 34 for ICD-10-CM. Chronic periodontitis falls under K05.31 (localized) and K05.32 (generalized), and each needs a sixth character for severity, such as K05.313 for localized severe disease. Point each procedure line to its diagnosis in item 29a.

Want a second set of eyes on how your recent GTR claims went out? Ask for a free billing review and we'll go through site counts, tooth numbers, and fee loading with you.

When Do Payers Consider GTR Medically Necessary?

Payers usually cover GTR at a natural tooth for two defect types: intrabony (vertical) defects and Class II furcations. UnitedHealthcare's GTR policy (DCP045.10, effective May 1, 2026) lists both. Its exclusion list runs longer, and it's the list a reviewer holds your D4266 dental code claim against. UHC says GTR isn't indicated for:

• Teeth with a poor or hopeless prognosis
• Uncontrolled metabolic, cardiovascular, or autoimmune conditions
• Medications that impair healing, including immunosuppressants, corticosteroids, anticoagulants, NSAIDs, and nicotine
• Patients who didn't comply with earlier therapy or who have poor oral hygiene
• Osseous defects with fewer than two walls, and crater defects
• Periapical lesions of endodontic origin

The VA's DNT-0005 criteria, effective July 1, 2026, name two more exclusions outright. They list current smoking or tobacco use and Grade III furcations as not clinically necessary. Before surgery, they also want documented maintenance compliance and systemic conditions under control.

Write the Tooth's Outlook (Prognosis) Into the Chart

UHC grades prognosis on the McGuire scale. Its policy calls a tooth hopeless when attachment can't support it and neither the clinician nor the patient can keep it clean enough to maintain. A poor grade fails too, since UHC excludes teeth with a poor or hopeless prognosis.

Ask the surgeon to record the grade and one line of reasoning in the pre-op note, such as "Prognosis fair; 2-wall defect, tooth maintainable." A note without a grade gives the reviewer nothing to approve.

D4266 Payer Rules in 2026: Cigna, UnitedHealthcare, and Aetna

Cigna, UnitedHealthcare, and Aetna each publish a GTR policy, and they don't ask for the same things. The table compares what each one says about the D4266 dental code in 2026. Policies change, so open the current version before you rely on it.

Cigna's PPO guide adds a rule that hits combined surgeries. Its D4265 policy (PERIO-08) doesn't allow biologics when other regrowth treatments happen at the same site on the same date. On a Cigna PPO claim with both on one tooth, plan for D4266 to pay and D4265 to deny. Cigna's DHMO plans use a separate guide.

Employer plans can also exclude periodontal surgery outright. Before you schedule, confirm D4266 coverage, frequency history, and whether the plan wants predetermination. If your front desk doesn't have time for code-level calls, our benefits verification runs $5 per check, or comes included with billing.

Medicaid Rules for D4266 Vary by State

Medicaid coverage for GTR depends on the state program and the managed care plan. Two published examples show the range:

• DentaQuest's Texas authorization catalog lists D4266 for ages 13 to 20, with review required and a narrative of medical necessity plus pre-op X-rays.
• AZ Blue's Medicaid dental prior authorization list, dated January 1, 2026, includes D4266.

Check your state's current provider manual and the plan's own authorization list before treatment, since the two don't always match.

Documentation That Gets D4266 Paid

Under UnitedHealthcare's claim review guideline DRG042.21, a D4266 dental code claim needs three attachments: a current dated pre-op radiograph, complete 6-point periodontal charting, and a narrative of necessity. Cigna's 5 mm and bone loss test and DentaQuest's Texas narrative-plus-X-ray rule point to the same packet, so build it once and send it every time.

Before surgery:

• Verify D4266 coverage, frequency history, and predetermination rules
• Take a current, dated periapical of the tooth
• Record 6-point probing depths for the tooth
• Chart the defect walls or the furcation class
• Write the prognosis grade with a one-line reason
• Confirm the site is a natural tooth, not a socket or an implant

On the claim:

• One line per site, each with a tooth number
• Membrane described as resorbable, with the product named
• Each graft, biologic, or blood concentrate on its own line
• Radiograph, charting, and narrative attached on first submission
• Date of service matching the surgical note

Attach everything to the first submission. A records request adds a full round trip before anyone at the payer looks at the clinical facts, and the claim ages the whole time.

D4266 Narrative Template

Fill the brackets from the chart and keep only facts a reviewer can check against the X-ray and charting.

Tooth #[ ] [mesial/distal/buccal]: [2-wall/3-wall] intrabony defect [or Class II furcation] with [ ] mm probing depth and vertical bone loss on the periapical dated [Month Day, Year]. Prognosis: [good/fair]; tooth is maintainable. [Scaling and root planing completed on (date), re-evaluated on (date), if applicable.] Guided tissue regeneration performed with a resorbable [collagen] membrane at this site. Bone replacement graft reported separately as D4263 [and biologic material (product) as D4265, if used]. No extraction, implant, or periradicular surgery at this site.

Edit the last two sentences to match the surgery. UHC's review guideline asks for the material name and application on D4265, so name the biologic product whenever that line is on the claim.

Why D4266 Gets Denied and How to Appeal

Denials on the D4266 dental code fall into a short list, and each one has a different fix. Read the reason code before you touch the claim. An appeal can't rescue a wrong code, and a corrected claim can't replace missing records.

For denials worth appealing, work in this order:

1. Match the EOB reason code to the payer's published D4266 policy.
2. Pull the dated periapical, the 6-point charting, and the surgical note, and confirm they match the date of service.
3. Write a one-page letter that answers the denial reason in the payer's own policy language.
4. File before the appeal deadline printed on the EOB or in the provider manual.
5. If the first level fails, ask whether the plan offers a dentist-to-dentist review and a second-level appeal. Medicaid managed care members can also request a state fair hearing.

If denied perio claims are piling up in your aging report, our AR follow-up team can work them for you.

What a Real D4266 Appeal Shows

MassHealth Appeal 2201575 is a public fair hearing decision on this exact code. A UnitedHealthcare Senior Care Options plan denied D4266 and D4263 on tooth #9 in January 2022, saying the X-rays didn't show a bone defect. The member lost the Level 1 appeal, and the hearing took place March 30, 2023.

After reviewing a provider letter and newer X-rays, UHC conceded that the records supported GTR. The hearing officer ordered a new approval for D4266. D4263 was dismissed as moot because the tooth had already been extracted, and the officer noted that code "is only appropriate for a natural tooth." The record closed May 22, 2023.

Three lessons carry over to any payer:

• The radiograph has to show the defect, since the original denial turned on images that didn't.
• A payer can't switch to a new denial reason at hearing without notice. The officer rejected UHC's late "no narrative" argument because the denial notice never raised it.
• An extraction changes the codes. Once #9 came out, the natural-tooth graft code no longer fit.

What Does D4266 Cost, and What Will Insurance Pay?

There's no national fee for D4266. The D4266 dental code cost a patient sees depends on the office fee, the plan's allowed amount for each site, and the patient's coinsurance, deductible, and remaining annual maximum.

Per-site billing multiplies all of it. Two sites mean two allowed amounts, two coinsurance shares, and twice the draw on the annual maximum. For an in-network estimate, use letters until you have the plan's numbers:

Per-site estimate (example letters only)

Plans don't all put periodontal surgery in the same benefit class, and the coinsurance follows the class. The real number comes from your contracted fee schedule, recent EOBs for D4266 from the same plan, and a predetermination. Medicaid pays the state fee schedule amount when the program covers D4266 at all.

Can D4266 Go to Medical Insurance?

Sometimes. Aetna's GTR bulletin calls the procedure dental-in-nature oral surgery and says such procedures "may be covered under either medical or dental plans." Whether a given medical plan pays depends on that plan's own terms, so check the medical policy before you count on it.

No CPT code matches GTR at a natural tooth one for one. If a medical plan accepts the ADA claim form, it still needs the K05.31 or K05.32 series diagnosis in item 34a with the "AB" qualifier, plus a narrative.

D4266 in CDT 2026 and CDT 2027

CDT 2026 took effect January 1, 2026, with 60 changes: 31 additions, 14 revisions, six deletions, and nine editorial changes. The VA's July 2026 template reprints the CDT 2026 descriptor with the same natural-teeth, resorbable, per-site wording.

For CDT 2027, the ADA approved 67 changes, made up of 28 additions, 33 revisions, and six editorial updates, effective January 1, 2027. The committee's March 2026 decisions report lists no action on the D4266 dental code or any other GTR code, and a requested D7953 revision was withdrawn by its submitter.

Code by date of service. A surgery on December 30, 2026, uses CDT 2026, and one on January 4, 2027, uses CDT 2027. Our breakdown of CDT 2027 changes covers the rest of the update.

D4266 FAQs

Short answers to common D4266 dental code questions from front desks and billers.

Is D4266 Covered by Insurance?

Usually, if the plan covers periodontal surgery and the chart shows a qualifying defect. Payers that publish GTR policies, including UnitedHealthcare and Cigna, accept dental code D4266 for intrabony defects or Class II furcations at a natural tooth. Cigna's PPO guideline wants pocket depths of 5 mm or more plus bone loss on X-rays.

Payment still runs through the plan's coinsurance, deductible, and annual maximum, and some employer plans exclude periodontal surgery. Verify the plan before scheduling, and request a predetermination when the fee is large enough that a surprise denial would strain the patient relationship.

Does D4266 Need Prior Authorization?

It depends on the plan and the program. Commercial dental plans set their own rules, so check whether the plan requires prior authorization for D4266 or only offers an optional predetermination. Some Medicaid programs require review before surgery, and their authorization lists spell out which codes need it.

DentaQuest's Texas catalog lists D4266 for ages 13 to 20 with review required, and AZ Blue's Medicaid prior authorization list dated January 1, 2026, includes D4266. Even when it's optional, a predetermination with charting, a dated periapical, and a narrative shows how the payer reads the case before the patient is in the chair.

Can D4266 and D4265 Be Billed on the Same Tooth?

Yes, when the surgeon used both. The codes report different things: D4266 is the barrier membrane, and D4265 is the biologic material, such as enamel matrix derivative, each reported per site. Put them on separate lines with the same tooth number, and name the biologic product in the narrative.

Payment is a separate question. Cigna's 2026 PPO guideline doesn't allow D4265 when another regrowth treatment happens at the same site on the same date, and it says the patient isn't responsible for that line. UnitedHealthcare wants the material name and how it was applied in the D4265 narrative. Set the patient estimate by each plan's rule.

Can a General Dentist Bill D4266?

Yes. CDT codes describe procedures and carry no specialty restriction. A general dentist who performs GTR within the state's scope of practice reports D4266 the same way a periodontist would. The ADA's 2026 graft guide says these regenerative graft procedures may be delivered and reported by any dentist or dental professional authorized by the state practice act.

Payers can still apply their own network and fee rules, and some plans pay specialists from a different fee schedule. Check the provider's network status before the first claim, and keep the same documentation standard a periodontist would use.

Can D4267 Be Used for Peri-Implant Defects?

No. D4267 is limited to natural teeth, the same as D4266. A non-resorbable membrane at an implant is D6107, and a resorbable one is D6106, both reported per implant. If a D4267 claim already went out for an implant, send a corrected claim with D6107 instead of appealing the denial.

Grafts that repair the peri-implant defect go on D6103, and the ADA graft guide says the membrane is reported separately from it. Cigna's PPO guideline also lists GTR at the site of an existing implant as not allowable under its natural-teeth policy, so check the plan's implant coverage before surgery.

Which Membrane Dental Code Applies at an Implant or Extraction Site?

Choose the membrane dental code by site. At an implant, report D6106 for a resorbable barrier or D6107 for a non-resorbable one, per implant. For an extraction socket or edentulous ridge, report D7956 or D7957, per site. A natural tooth takes D4266 or D4267, and with periradicular surgery it's D3432, which has no non-resorbable version.

That means the resorbable membrane dental code changes four ways: D4266, D6106, D7956, or D3432. The GTR code comparison table above lays them out side by side.

Before Your Next Regenerative Claim Goes Out

Run three checks on each D4266 dental code line before the claim leaves the office:

1. Is the site a natural tooth, and does each separate defect have its own line?
2. Does each graft, biologic, or blood concentrate have its own code and line?
3. Are the dated periapical, 6-point charting, and narrative attached?

If you'd rather hand these claims to a team that works dental claims full time, iDental Billing offers outsourced dental billing, including periodontal billing services for practices and DSOs. Billing pricing runs from 3.95% down to 2.95% of monthly collections based on volume, with nothing charged on unpaid or denied claims.

Sources

• American Dental Association, Guide to Reporting Wound Dressings (August 2021)
• American Dental Association, Guide to Graft Material Collection, 2026
• American Dental Association, Dental Claim Data Recommendation: Area of the Oral Cavity and Tooth Anatomy (January 1, 2025)
• American Dental Association, Final Report of March 2026 Code Maintenance Committee Decisions
• ADA News, 67 Changes Coming to CDT 2027 (April 14, 2026)
• ADA News, 60 Changes Coming to CDT Code in 2026 (June 5, 2025)
• U.S. Department of Veterans Affairs, CDI DNT-0005: Dental Barrier Membrane Guided Tissue Regeneration (July 1, 2026)
• UnitedHealthcare, Dental Barrier Membrane Guided Tissue Regeneration, DCP045.10 (May 1, 2026)
• UnitedHealthcare, National Standardized Dental Claim Review Guidelines, DRG042.21 (January 1, 2026)
• UnitedHealthcare, Biologic Materials, DCP047.05 (May 1, 2026)
• Cigna Healthcare, Dental Clinical Coverage Determination Guidelines, DPPO and Indemnity, 999493 (May 2026)
• Aetna, Dental Clinical Policy Bulletin DCPB002: Guided Tissue Regeneration
• Commonwealth of Massachusetts, Board of Hearings, Appeal 2201575
• DentaQuest, Texas Authorization Catalog
• AZ Blue, Medicaid Dental Prior Authorization Codes List (January 1, 2026)

CDT is a trademark of the American Dental Association, which holds the copyright to the CDT Code. Code titles in this guide are paraphrased except where quoted.