D4346 Dental Code: Scaling for Moderate to Severe Gingivitis

The short version

D4346 is the CDT code for a full-mouth scaling performed on a patient with widespread gum inflammation but no periodontitis. It covers removing plaque, calculus, and stain above and below the gumline when a patient has generalized moderate or severe gingivitis and no bone loss. Offices that don't use it bill those visits as D1110, and that undercharges every one of them.

• Bill D4346 when the evaluation finds moderate or severe gingival inflammation on 30% or more of the teeth and the radiographs show no bone loss.
• It follows an evaluation (D0120, D0150, or D0180), same day is fine. It's billed once per treatment episode, and never on the same date as a prophy, SRP, or debridement.
• The neighbors: healthy gums are D1110, bone loss is D4341/D4342, and gingivitis in between is D4346.
• Plans pay D4346 as a periodontal service, commonly around 80%, not a 100% preventive benefit. The patient usually owes something, so tell them before the visit.
• Billing these visits as D1110 costs real money: $13.50 per visit on Michigan's Medicaid schedule, about 23% of the fee.
• The claim gets paid with three things: a written gingivitis diagnosis, a perio chart from the last 12 months with bleeding points marked, and radiographs showing no bone loss.

The sections below walk through each of these with the payer documents cited, and the sidebar jumps to any of them.

What is D4346?

D4346 documents a therapeutic, full-mouth scaling for a patient who was just diagnosed with generalized moderate or severe gingivitis. The gums are swollen and bleed on probing, and probing may find deeper readings from swollen tissue (pseudo-pockets), but the CDT descriptor limits the code to inflammation "in the absence of periodontitis." The patient has no attachment loss and no bone loss. The ADA added the code in 2017 because there was no way to bill gum treatment for a patient who was past a healthy cleaning but not yet a perio patient. The descriptor is unchanged through CDT 2026, per the ADA's Code Maintenance Committee reports.

Billers know the appointment this code was made for: the recall patient whose schedule says "prophy" and whose chart shows bleeding at nearly every probe site.

When do you bill D4346?

Bill D4346 when the evaluation finds moderate or severe gingival inflammation on 30% or more of the patient's teeth and the radiographs show no bone loss. The ADA's Guide to Reporting D4346 spells out each piece of that:

• Generalized means 30% or more of teeth involved. The ADA guide points to the AAP's definition of generalized disease (30% or more of teeth affected at one or more sites) and extends it to gingivitis.
• Moderate or severe comes from the gingival index. Moderate inflammation shows redness, swelling, and bleeding on probing. Severe shows marked redness and swelling with a tendency to bleed spontaneously.
• No periodontitis. Pseudo-pockets are expected. Attachment loss or radiographic bone loss disqualifies the code and points to D4341 or D4342 instead.
• An evaluation comes first. D4346 follows a D0120, D0150, or D0180, and the ADA confirms the evaluation and the scaling can happen on the same date of service.
• The diagnosis drives the code, not the effort. A long, difficult prophy on a patient without generalized inflammation is still D1110. The ADA guide says this directly about so-called hard prophies.

D4346 vs D1110, D4341, and D4910

These four codes get confused because they all involve scaling. The gum condition and the bone decide which one applies.

The Medicaid rates in the table are from Michigan's dental fee schedule (January 2024), a public floor you can check any code against.

The miscode that costs the most is billing D1110 for a patient with generalized gingivitis. On the Michigan schedule that's a $13.50 difference per visit, about 23% of the fee, and commercial contracted fees show the same spread. The reverse mistake gets the claim denied instead: billing D4346 when the radiographs show bone loss. Cigna's clinical guidelines, for example, reserve D4341/D4342 for quadrants with 4 mm+ pockets plus bone loss, and a payer that sees bone loss on your films expects the SRP codes, not D4346.

One more neighbor worth naming: D4355, full-mouth debridement. D4355 happens before the evaluation, when heavy deposits block the exam. D4346 happens after the evaluation and diagnosis. Delta Dental's clinical criteria allow D4355 once per lifetime. So if heavy deposits blocked the exam, bill the debridement, bring the patient back, and make the gingivitis diagnosis at the follow-up evaluation.

What does insurance actually do with D4346?

Plans commonly treat D4346 as a periodontal service instead of a preventive one, and that changes the patient's share. HealthPartners' published policy states it plainly: D4346 is "benefitted as a periodontal service rather than a preventive procedure," billed once per treatment episode no matter how many visits it takes, and limited to once every two years on their plans. Other carriers set their own limits, so a pre-determination is worth the week it takes on any plan you haven't billed this code to before.

Here's what that benefit class does to the money on a typical PPO claim, where the $160 office fee goes:

• Your office fee for D4346 is $160
• The PPO contracted fee is $120, so you'll write off $40 when you post the payment
• The plan covers D4346 as a periodontal service at 80%, so insurance pays $96
• The patient owes $24

Now bill that same visit as D1110 instead: contracted fee $90, covered at 100% as preventive, insurance pays $90, the patient owes nothing, and the office collected $30 less for the same chair time. Multiply by every bleeding-gums recall patient on the hygiene schedule and the undercoding habit has a real annual cost. There's a front-desk side to the same math: a patient who's used to free cleanings needs to hear about the $24 before the appointment, not on the statement. If the write-off posting part of this is fuzzy, here's how to post a dental insurance adjustment step by step.

Attachment rules are per-payer. HealthPartners wants a diagnosis statement, full-mouth probing with bleeding sites, and current radiographs with the claim. Delta Dental's clinical criteria, on the other hand, list D4346 among the codes that don't require submitted perio charting. Don't read that as permission to skip the charting. The ADA's guide says the patient record should hold charting and radiographs from within the last year, and when Delta does ask for charting, it accepts nothing older than 12 months.

On fees: Medicaid schedules are the only numbers a guide can print with a hard citation, and Michigan pays $71.25 for D4346. The ADA's guide says a dentist might set the D4346 fee between the office's D1110 and D4341 fees, and that each office decides its own number. Before you set yours, look at those two fees on your own schedule and check the claims-based ranges for your zip code on FAIR Health Consumer.

Why does D4346 get denied?

The denials are predictable. Five reasons cover almost all of them:

• The perio chart shows localized inflammation, not generalized. Under 30% of teeth involved reads as a D1110 to the payer.
• The radiographs show bone loss, so the payer expects D4341/D4342 instead.
• D4346 was billed on the same date as a prophy, SRP, or debridement, which the descriptor forbids.
• The plan already paid a D4346 inside its frequency limit (HealthPartners allows one every two years).
• The chart has probing depths but no bleeding sites, so the claim can't show the inflammation is generalized.

What documentation gets D4346 paid?

The documentation that gets it paid, in order:

1. A written diagnosis in the chart notes: generalized moderate or severe gingivitis, no periodontitis.
2. A full-mouth perio chart dated within 12 months, with probing depths and bleeding points marked. Bleeding should show throughout the mouth, not on a few teeth.
3. Current radiographs that show no bone loss. HealthPartners accepts bitewings.
4. Intraoral photos of the inflammation. Both the ADA and HealthPartners call photos helpful support.
5. The evaluation code (D0120, D0150, or D0180) on the same or a prior date.

If a clean claim still comes back denied, the appeal narrative states the diagnosis, the percentage of teeth with bleeding on probing, and the absence of radiographic bone loss, and attaches the chart and films. Here's how to appeal a dental insurance claim denial with the full letter structure, and it's worth the effort, because most denied dental claims are never appealed at all.

Common questions about D4346

How soon after D4346 can the patient have a regular cleaning?

There's no set waiting period. The ADA's D4346 guide leaves the interval to the dentist: once the tissue heals, the patient goes back on a normal preventive schedule with D1110. The plan's prophy frequency limits still apply to those later cleanings, so check the patient's benefits before you book the follow-up.

Does D4346 have to be finished in one visit?

Usually it is, but it doesn't have to be. The ADA guide allows the scaling to run over more than one visit for patient comfort, and the date of completion becomes the date of service. You bill the code once per treatment episode either way. HealthPartners' policy states the same rule: one charge regardless of the number of visits.

Can you bill D4346 for a patient with implants?

No. The descriptor covers plaque, calculus, and stain on natural tooth surfaces. Scaling an implant with mucositis is D6081, and the ADA guide notes D6081 and D4346 can't be billed on the same date of service. For a patient with both natural teeth and an inflamed implant, plan the visits accordingly.

How much does D4346 cost?

Fees vary by region and by contract. Michigan Medicaid pays $71.25 for D4346 (January 2024 schedule), which works as a public floor. Commercial office fees commonly sit between the office's own D1110 and D4341 fees, and FAIR Health Consumer shows claims-based ranges for your zip code.

Find the money you're already earning

This afternoon, pull the perio charts from last month's hygiene schedule and count the patients with generalized bleeding on probing who went out the door as a D1110. Each one is a visit the office undercoded, and each future one is fixable at the front desk with a diagnosis note and the right code. Checking every hygiene claim against the charting is exactly the kind of repetitive work that never gets staffed, which is why Autumn does it as part of the billing it runs for your office.

Sources

• ADA, Guide to Reporting D4346
• ADA, D4346 webinar page (code introduced 2017)
• ADA, March 2026 Code Maintenance Committee final report
• HealthPartners, dental policy: Code D4346
• Delta Dental, clinical criteria and utilization management (effective January 1, 2025)
• Cigna, dental clinical coverage determination guidelines, DHMO 2026
• Michigan MDHHS, Medicaid dental fee schedule
• FAIR Health Consumer, dental cost lookup

CDT codes and nomenclature are copyright © American Dental Association. This guide explains the code in plain language; the current CDT manual is the authoritative source.