Ask a dental team which code covers periodontal charting, and most will answer D0180. The 2026 revision to the D0180 descriptor now spells out “full mouth probing and periodontal charting” as part of the code. Useful wording, but it has hardened the idea that D0180 is “the perio charting code.” It isn’t: There is no code for periodontal charting.
Charting is a diagnostic component
Periodontal charting is not a billable procedure. You perform it, you document it, and you report an evaluation. In SOAP (subjective, objective, assessment, and plan) clinical note terms, the charting is the objective: the measured findings that support a diagnosis and a treatment plan. The O is the clinical data behind the diagnosis.
That is why the coding committee has never given charting its own code. The revised D0180 code reads as a comprehensive periodontal evaluation that includes full-mouth probing and charting. The charting lives inside the exam codes.
The 3 evaluation codes
Estela Vargas, CRDH.
Three clinical evaluation codes come up most in a periodontal context. Reading each descriptor is what keeps the coding clean.
- D0120 periodic oral evaluation -- established patient. The CDT 2026 descriptor states: “An evaluation performed on a patient of record to determine any changes in the patient's dental and medical health status since a previous comprehensive or periodic evaluation. This includes an oral cancer evaluation, periodontal screening where indicated, and may require interpretation of information acquired through additional diagnostic procedures. The findings are discussed with the patient. Report additional diagnostic procedures separately.”
D0150 comprehensive oral evaluation -- new or established patient. The CDT 2026 descriptor states: “Used by a general dentist and/or a specialist when evaluating a patient comprehensively. This applies to new patients; established patients who have had a significant change in health conditions or other unusual circumstances, by report, or established patients who have been absent from active treatment for three or more years. It is a thorough evaluation and recording of the extraoral and intraoral hard and soft tissues. It may require interpretation of information acquired through additional diagnostic procedures. Additional diagnostic procedures should be reported separately. This includes evaluation of oral cancer, the evaluation and recording of the patient’s dental and medical history, and a general health assessment. It may include evaluation and recording of dental caries, missing or unerupted teeth, restorations, existing prostheses, occlusal relationships, periodontal conditions (including periodontal screening and/or charting), hard and soft tissue anomalies, etc.”
- D0180, comprehensive periodontal evaluation -- new or established patient. The CDT 2026 descriptor says: “A comprehensive evaluation of periodontal conditions, including full mouth probing and periodontal charting. Indicated for patients exhibiting signs or symptoms of periodontal disease, systemic medical conditions, or patients with social risk factors. It includes an evaluation of current dental conditions.”
Report the code for the visit you actually delivered -- not two of them for one appointment, and not the highest-value one -- the one you did.
The trap: Billing D0180 when it was a D0120
The mistake I see is that rarely practices bill D0120 and D0180 together. More often, it is reaching for D0180 on a routine recall that is due for annual periodontal charting that was really a D0120. It pays more and requires more time, so it feels justified, but it is still upcoding, even when no one intends it.
D0180 is appropriate for an existing patient who presents with signs or symptoms of periodontal disease, systemic medical conditions, or social risk factors. It also applies when a returning patient’s history itself is a risk factor: The CDT 2026 Coding Companion uses D0180 in worked scenarios involving prolonged absence from active treatment, including a two-year hiatus with worsening findings and a recall visit for a patient who has been away for over a decade.
The ADA recommends annual periodontal charting and evaluation for any patient with a history of periodontitis, and the American Academy of Periodontology has established the comprehensive periodontal evaluation as part of the standard of care for periodontal therapy. Probing a returning patient is expected. It does not upgrade the code.
The provider makes the final call on the code and the diagnosis, and that is where it belongs. None of this overrides clinical judgment. It means knowing what each code describes before you choose.
A case that trips everyone
A patient of record comes in for a routine recall. On her updated medical history, she reports a new diagnosis of type 2 diabetes. That is the subjective, the S in the SOAP note. The hygienist probes, finds new bleeding and deeper pockets than the last visit, and the dentist completes a full-mouth periodontal evaluation.
Is it a D0120 because she is established? No. The new risk factor and the new findings move it to D0180, even though her last charting was under a year ago. The updated medical history is what reclassifies the visit.
And it is not only diabetes. The risk factors worth keeping front and center include a new or rising HbA1c, newly started or resumed smoking or vaping, a medication that is altering the gingiva, pregnancy and other hormonal shifts, and immunosuppression, including patients in cancer treatment. Any one of them can change the evaluation code for a returning patient.
Documentation that holds up
If the charting is your objective record, it must be complete enough to defend the code: six-point pocket depth readings per tooth, recession, clinical attachment loss, bleeding on probing, suppuration, furcation, mobility, mucogingival junction measurements, plaque and calculus assessments, and gingival inflammation assessment.
The diagnosis is written into the record, alongside the staging and grading. And the charting is dated and repeated over time so progression or stability is visible in the record.
So, what do you report?
How do you code for perio charting? You don’t. You code the evaluation the charting was part of. Match it to the patient in front of you: D0120 for the established recall, D0150 for the comprehensive exam, D0180 for the periodontal patient. Document the charting and the diagnosis the code requires, report the one you performed, and it holds up to anyone who reviews it.
Editor's note: References available upon request.
Estela Vargas, CRDH, is the founder and CEO of Remote Sourcing, a dental insurance billing and revenue recovery service. She is a graduate of Miami Dade College's dental hygiene program. Vargas' extensive background in the clinical arena of dentistry is coupled with her experience as a practice administrator and business executive.
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