Periodontal Codes Explained: D4341, D4342, D4346, D4910

Periodontal Codes Explained: D4341, D4342, D4346 and D4910

Periodontal claims are where good clinical care and payer rules most often disagree. The same hygiene appointment can be billed as a prophylaxis, gingival inflammation scaling, scaling and root planing, debridement, or periodontal maintenance, and each has its own documentation expectations, frequency limits, and denial patterns. Choosing the right code is half the job. The other half is reading what the payer actually did with it once the EOB comes back.

What is the difference between D1110, D4346, D4341, D4342, D4355 and D4910?

These six codes describe different clinical situations, not different intensities of the same cleaning. The code has to match what the chart shows: the patient's periodontal status, whether there is bone or attachment loss, how many teeth are involved, and whether active periodontal therapy already happened. The official descriptors live in the ADA's CDT manual. The summaries below are plain-language billing guidance, and if you need a refresher on how CDT codes work in general, start with Zentist's guide to dental billing and coding basics.

When should you bill D4346 instead of D1110?

Bill D4346 when the evaluation shows generalized moderate or severe gingival inflammation but no bone or attachment loss. The ADA created the code in 2017 to fill the gap between prophylaxis and scaling and root planing, and its Guide to Reporting D4346 is clear that a "hard prophy" defined only by time in the chair does not qualify. The guide also notes that D4346 is not reported on the same date as a prophylaxis, scaling and root planing, or debridement.

The chart should document the evaluation, the extent of inflammation and bleeding, probing results, and the absence of bone loss. Coverage is where D4346 gets complicated: some plans pay it, some don't cover it, and some pay it at a prophylaxis level and leave the difference as a write-off or patient balance. That last outcome is easy to miss when EOBs are posted by hand. Remit AI reads each EOB and ERA, and its Autoposting tool posts the allowed amount and adjustment exactly as the payer processed them, so a quiet downgrade shows up as a downgrade instead of disappearing into the ledger.

How do you choose between D4341 and D4342?

The choice comes down to tooth count per quadrant. Both are scaling and root planing codes for patients with periodontitis, meaning bone and attachment loss, which is what separates them from D4346, as the California Dental Association explains. Use D4341 when four or more teeth in a quadrant need the procedure and D4342 when one to three do. A full mouth often mixes both, such as two quadrants of D4341 and two of D4342.

Scaling and root planing claims carry the heaviest documentation load in this group. Payers commonly expect full-mouth periodontal charting, radiographs that show bone loss, a periodontal diagnosis, and a clear tooth count per quadrant, and many limit how often each quadrant can be treated. The usual denials follow from those expectations: missing charting or radiographs, probing depths without supporting bone loss, frequency limits, or a D4341 recoded to D4342 when the tooth count doesn't support four teeth.

When is D4355 the right code?

D4355 is right only when heavy deposits keep the dentist from completing a comprehensive periodontal evaluation, and the evaluation happens on a later visit. According to ADA News, it can be reported on the same date as a periodic or comprehensive oral evaluation but not with a comprehensive periodontal evaluation (D0180), and it can't be reported at a second visit once the evaluation was already completed.

The chart should explain why the evaluation couldn't be done and record the plan to complete it. Many plans cover D4355 sparingly or not at all, so it is denied most often when it is used as a "heavy cleaning" label, billed after the evaluation, or paired with an excluded same-day service.

What does a D4910 claim need to get paid?

D4910 needs proof that the patient completed active periodontal therapy, such as scaling and root planing, before maintenance began. Payers look for that history, so if the original therapy was done at another practice or under a different plan, include the dates and records with the claim. Current charting and the maintenance interval the dentist set should be in the note as well.

D4910 is also one of the codes most often paid at a lower level. Some plans count periodontal maintenance against the same frequency as routine cleanings or pay it at the D1110 rate, which means the practice sees a downgrade, not a denial. Frequency is a recurring problem across dental claims: in a Zentist analysis of a large multi-location DSO, frequency limits accounted for 8.2% of all denials, as covered in the top 5 dental claim denial reasons. Remit AI's eligibility checks surface frequency limits before the visit, so the team can set the patient's expectations before the claim ever goes out.

How does Remit AI help with periodontal denials and downgrades?

Remit AI turns periodontal EOBs into clear next steps instead of a stack of adjustment codes, and periodontal claims need that more than most. In an industry survey of dental billing teams reported by DentistryIQ, D4341 ranked first among the codes that most often require supporting documentation, and it was among the claims payers most often rejected on first submission.

Zentist's own claims data shows where those denials land. In an analysis of denials at a large multi-location DSO, covered in Zentist's top 5 dental claim denial reasons, non-covered charges made up 35.24% of all denials and frequency limits made up 8.20%. Those are the two walls periodontal claims hit most, because coverage for codes like D4346 and D4355 varies by plan and D4910 is tightly frequency-limited. Across all procedures, Zentist's 2026 Dental Claims Denial Benchmark Report, built on 22.4 million procedure-level service lines, found that more than 80% of denials come from preventable administrative errors, which is exactly the kind of error missing perio charting or a skipped frequency check creates.

Remit AI collects EOBs and ERAs from 725+ payers with no portal logins, and Autoposting posts each payment, adjustment, and downgrade into the practice management system. Denials are translated into plain-English reasons with a recommended action, so the team can tell at a glance whether a D4341 needs charting attached for an appeal, a D4910 hit a frequency limit and belongs on the patient's balance, or a D4346 was paid at a prophylaxis level as the plan allows. Remit AI then reconciles each payment against the bank deposit. For claims rejected before adjudication, Caviar's agentic claims review uses an AI agent to diagnose and resubmit rejections, including those missing documentation, and flags anything that still needs a person.

What do real periodontal billing scenarios look like?

A patient with generalized moderate inflammation, heavy bleeding, and no bone loss on radiographs fits D4346, not D1110 or scaling and root planing. Attach the charting and a short narrative so the payer can see why the visit was more than a routine cleaning.

A patient with bone loss in all four quadrants, but only two teeth affected in the lower left, is billed as D4341 for the three quadrants with four or more teeth and D4342 for the lower left, with full-mouth charting and radiographs attached.

A patient returning three months after completing scaling and root planing is billed D4910, with the prior therapy dates in the record. If the EOB pays it at the D1110 level, that usually reflects the plan's benefit rules rather than a coding error, and the difference should be posted as the plan processed it.

See how Remit AI handles periodontal EOBs

Remit AI automates EOB collection, payment posting through Autoposting, reconciliation, and denial management for 5,000+ dental practices, so downgrades and denials on periodontal claims get caught and worked instead of written off. See how Remit AI works.