D4240 is the CDT code for a gingival flap procedure including root planing on four or more contiguous teeth per quadrant. The surgeon reflects the gingival tissue, cleans and planes the root surfaces under direct vision, and closes the flap. It is billed per quadrant and requires documented prior non-surgical treatment.
Last updated June 2026 · Reviewed by the PracticeAlpha billing team
Get help with D4240 claims →Non-surgical scaling and root planing has been completed and re-evaluated. Pockets remain deep enough that adequate root debridement cannot be achieved without reflecting tissue. Open access allows direct vision and instrumentation of root surfaces.
Heavy subgingival deposits extending to the base of deep pockets that cannot be fully removed by closed scaling. Flap reflection provides direct access to root anatomy, furcations, and calculus that are not reachable with blind instrumentation.
Furcation involvement, root concavities, or anatomical features that make thorough root planing impossible without tissue reflection. The flap procedure allows complete debridement and closure of the surgical site.
Do NOT use D4240 for: Non-surgical scaling without a flap (use D4341 or D4342). Procedures involving one to three teeth in a quadrant (use D4241). Any procedure where bone is surgically reshaped or removed (use D4260 osseous surgery). Procedures where the primary intent is biopsy or lesion removal.
Most plans treat D4240 as a surgical follow-up to non-surgical treatment. If there is no record of prior D4341 or D4342 in the patient's history, the surgical claim is denied. Include dates, quadrants, and the re-evaluation appointment that showed insufficient resolution.
A narrative stating "patient has periodontal disease" is not enough. Payers expect periodontal charting with specific pocket depths recorded at six points per tooth for every tooth in the treated quadrant. Charts from multiple timepoints showing persistent or progressing pockets strengthen the claim significantly.
Many plans require a waiting period between non-surgical scaling and surgical intervention, commonly six to twelve weeks, to allow for re-evaluation. Submitting D4240 before that interval has passed will result in a denial. Document the SRP date, the re-evaluation date, and the persistent findings that indicate surgery is now needed.
Periapical radiographs showing bone levels are a standard requirement for surgical perio claims. Films more than 12 to 18 months old may not satisfy the payer. Submit current radiographs that demonstrate alveolar bone loss consistent with the clinical findings and the quadrant being treated.
Six-point pocket depths, bleeding on probing, recession, furcation classification, and mobility for all teeth in the treated quadrant. Include charts from the initial diagnosis, from just before the prior SRP, and from the re-evaluation showing that pockets persist.
Recent films covering the quadrant being treated. Radiographs should demonstrate bone levels and confirm alveolar bone loss. Submit images dated within the past 12 to 18 months at minimum. Include in the claim or pre-authorization package.
Dates and quadrants of prior D4341 or D4342, along with clinical notes from the re-evaluation appointment. The re-evaluation notes must show that the patient was compliant and that pockets did not adequately resolve, establishing medical necessity for the surgical step.
Detailed notes describing the flap design, findings on reflection (calculus deposits, root anatomy, bone morphology), root planing performed, and closure technique. Notes should confirm that the procedure involved four or more contiguous teeth in the quadrant.
Many plans require prior authorization before approving periodontal surgical codes. Submit the pre-auth with charts, x-rays, and SRP history. Record the authorization number and include it on the claim. Missing auth when it was required is a routine reason for denial.
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Learn about our billing servicesD4240 is the CDT code for a gingival flap procedure including root planing on four or more contiguous teeth per quadrant. The surgeon reflects the gingival tissue, debrides and planes the root surfaces under direct vision, and closes the flap. It is billed per quadrant.
D4341 is non-surgical, performed without a flap. D4240 involves surgically opening the tissue for direct access to root surfaces. D4240 is used after D4341 has been completed and re-evaluated and pockets have not adequately resolved. Most plans require documented prior SRP before approving D4240.
The most common reasons are lack of prior SRP records, insufficient periodontal charting, submitting the claim too soon after non-surgical treatment, and missing or outdated radiographs. Including a complete treatment sequence with charting and re-evaluation notes prevents most denials.
A full periodontal chart with six-point pocket depths; current periapical radiographs; prior SRP records with dates and quadrants; re-evaluation notes showing persistent disease; surgical procedure notes confirming the flap, root planing, and closure on four or more contiguous teeth per quadrant.
D4240 involves reflecting a flap and root planing without reshaping bone. D4260 includes the same flap elevation plus surgical recontouring or resection of the alveolar bone. If bone surgery is performed, D4260 is the correct code. D4240 should not be billed when osseous surgery is also done in the same quadrant.
No. These should not be billed for the same quadrant on the same date. D4341 is the non-surgical step performed first. D4240 is the surgical follow-up performed at a later appointment after re-evaluation. Billing both for the same quadrant on the same day is a coding error and will be denied.
Search all 206 CDT codes in our dental coding guide.