D4342 is the CDT code for periodontal scaling and root planing (SRP) on one to three teeth in a single quadrant — the same therapeutic deep cleaning as D4341, but for a limited number of qualifying teeth rather than a full quadrant.
Informational only — confirm the official CDT descriptor and your payers' rules independently. This is general guidance, not billing, coding, or clinical advice.
When to Use the D4342 Code
Report D4342 when scaling and root planing is performed on one to three teeth within a quadrant that show clinical signs of periodontitis — probing depths of 4 mm or greater, radiographic bone loss, bleeding on probing, and subgingival calculus. It is a definitive, non-surgical therapeutic procedure for localized periodontal involvement.
The key distinction is the tooth count: D4341 is reported when four or more teeth in the quadrant qualify, and D4342 when only one to three do. Do not substitute D4342 for a routine adult prophylaxis (D1110) or for full mouth debridement (D4355), which are different procedures. Surgical periodontal care, such as D4240, is also coded separately.
Documentation & Clinical Scenarios
Because D4342 is reported by quadrant and tooth count, the chart must clearly establish localized periodontal disease:
- Periodontal charting identifying the specific one to three teeth with pockets of 4 mm or greater.
- Recent radiographs showing localized bone loss.
- Bleeding-on-probing and calculus notes supporting medical necessity.
- A periodontal diagnosis and a narrative when the payer requests one.
The teeth treated must be documented by number so the limited scope is clear. A re-evaluation typically follows; once active therapy is complete, recall may shift to periodontal maintenance (D4910).
Insurance & Billing Tips
- Verify benefits first. Confirm SRP coverage, frequency limits, and the documentation the plan requires.
- Match the code to the count. Use D4342 only when one to three teeth in the quadrant qualify; billing D4341 for a localized case is a common error.
- Attach the evidence. Charting and radiographs for the specific teeth reduce denials and support the limited-scope claim.
- Watch down-coding. Payers may down-code SRP to a prophylaxis; documentation supports an appeal.
- Avoid mixing prophy and SRP loosely. Some plans scrutinize SRP performed on the same date or quadrant as a cleaning — confirm the plan's rules.
Example Case
A 47-year-old patient returns with localized deep pockets around teeth #2, #3, and #14. Charting shows 5 mm pockets with bleeding and bitewings reveal localized bone loss, while the rest of the mouth is healthy. The dentist performs scaling and root planing on these three teeth in the upper right quadrant and tooth #14 in the upper left. The upper right is reported as D4342 (three teeth), and the single tooth in the upper left as another D4342, each with charting and radiographs attached.
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Frequently Asked Questions
When do I use D4342 instead of D4341?
The deciding factor is how many teeth in the quadrant qualify for treatment. D4342 is for one to three teeth per quadrant; D4341 is for four or more. Both describe the same scaling and root planing procedure, so the choice is purely about the qualifying tooth count. Billing D4341 when only one to three teeth are involved is a frequent denial trigger, so confirm the count before coding each quadrant.
Is D4342 just a partial cleaning?
No. D4342 is a therapeutic procedure for diagnosed periodontitis on specific teeth, not a routine cleaning. A standard prophylaxis (D1110) is preventive and applies to a healthy mouth, while D4342 removes calculus and biofilm from root surfaces below the gumline on the affected teeth. A perio diagnosis with charting and radiographs supports the code.
How often is D4342 covered by insurance?
Coverage varies, but many plans apply a frequency limit per quadrant and require documented pockets, bone loss, and bleeding. Because D4342 is localized, some payers review the supporting charting closely to confirm the limited scope. Verify the plan's specific frequency and documentation rules before treatment.
Does D4342 need a pre-authorization?
A pre-treatment estimate is often recommended even for localized SRP, since payers review these claims. Submitting periodontal charting and radiographs for the specific teeth confirms the diagnosis and the limited scope, establishes remaining benefits, and reduces the chance of a denial or a down-code to a prophylaxis.
Confirm the current CDT descriptor and your specific payer policies before billing — browse the full dental code library or see our insurance verification feature.