> ## Documentation Index
> Fetch the complete documentation index at: https://dso.getlemma.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Clinical & billing code sets overview

> The dental code-set map: CDT and its licensing, ICD-10-CM's situational role, tooth numbering on the ADA claim form, taxonomy and POS, and where CPT/HCPCS enter for medical crossover.

This page maps the code sets that appear on dental claims and the medical code sets a dental group encounters in crossover billing. Different organizations maintain them, some require licenses, and using the wrong set can cause denials.

**Licensing matters.** CDT is copyrighted and licensed by the ADA; CPT by the AMA. This page describes what each code set is and uses a small number of illustrative codes. It does not reproduce licensed code lists. If you are building software that embeds these codes, you need a commercial license from the maintainer.

## The code sets

| Code set            | Maintained by                       | Describes                                  | Where it appears                                                         | Licensed?      |
| ------------------- | ----------------------------------- | ------------------------------------------ | ------------------------------------------------------------------------ | -------------- |
| **CDT**             | American Dental Association         | Dental procedures                          | **837D `SV3` service lines**; your claims                                | **Yes, ADA**   |
| **ICD-10-CM**       | CDC/NCHS (US clinical modification) | Diagnoses                                  | 837D where the payer requires it; required on medical crossover claims   | No             |
| **Tooth numbering** | ADA (as used on the ADA claim form) | Which tooth, which surface, which quadrant | 837D tooth information; ADA claim form                                   | Not applicable |
| **CPT**             | American Medical Association        | Medical procedures and services            | 837P service lines; **crossover only**                                   | **Yes, AMA**   |
| **HCPCS Level II**  | CMS                                 | Supplies, appliances, DME                  | 837P; crossover, sleep appliances, DMEPOS                                | No             |
| **Taxonomy codes**  | NUCC                                | Provider type and specialty                | 837 `PRV`, NPPES, enrollment                                             | No             |
| **POS codes**       | CMS                                 | Where the service was delivered            | Medical claims' `CLM05`; payment-relevant in crossover                   | No             |
| **NDC**             | FDA                                 | Drug products                              | Rare in dental; some Medicaid programs require it for administered drugs | No             |

## CDT: the primary code set

Every service line on a dental claim carries a **CDT** code; "D" plus four digits, organized into twelve service categories from diagnostic (D0100–D0999) through adjunctive general services (D9000–D9999). CDT is the HIPAA-designated code set for dental services (45 C.F.R. § 162.1002), updated annually effective January 1, and copyrighted by the ADA; purchase of the CDT manual covers use in your own practice and PMS, while embedding the codes in a commercial product requires an ADA license.<sup>1</sup>

Structure, licensing, and the update cycle are covered in depth in [CDT & the 837D](/reference/edi/cdt-and-837d). This wiki describes the system and uses only illustrative codes instead of reproducing the licensed list.

## ICD-10-CM: situational, and growing

Diagnosis codes are **not the organizing principle of dental billing** the way they are in medical; a dental claim is adjudicated on the CDT code plus tooth-level anatomy and history. But ICD-10-CM shows up in three places:

* **Payer-by-payer requirements.** Some dental payers and many Medicaid dental programs require diagnosis codes on some or all claims. Your payer's companion guide governs; treat "does this payer want diagnoses?" as an enrollment-time question.
* **Medical crossover.** On an 837P for oral surgery, sleep appliances, or trauma, ICD-10-CM diagnoses affect adjudication and support medical necessity. See [Bill medical plans for dental work](/guides/billing/bill-medical-for-dental-work).
* **Clinical documentation.** Diagnosis-coded dental records support medical-necessity narratives and appeals even where the claim itself doesn't require the code.

ICD-10-CM updates annually on **October 1**, while CDT updates on January 1.

## Tooth numbering and anatomy detail

Dental claims carry anatomy fields that medical claims do not: tooth number, tooth surfaces, and oral cavity designation (quadrant or arch). On the ADA Dental Claim Form and the 837D, US practice uses the **Universal/National tooth designation system**; permanent teeth are numbered 1 through 32, primary teeth are lettered, and surfaces use letter codes.<sup>2</sup> The ADA's claim-form completion instructions are the primary reference for tooth, surface, and area-of-oral-cavity reporting. International records may use the two-digit ISO/FDI system, which does not appear on US claims.

Payers use this information to apply tooth-specific history, including crown replacement intervals, missing-tooth clauses, and prior restorations by surface. A missing tooth number or a surface count that does not match the procedure can cause a rejection or denial. See [837D file anatomy](/reference/edi/837d-anatomy).

## CPT and HCPCS: crossover only

A dental group generally uses CPT and HCPCS Level II when **billing medical plans** for work with a medical indication, such as oral surgery, pathology, trauma, sleep appliances, or a Medicare-covered service. Those claims use the 837P with CPT or HCPCS and ICD-10-CM, require the appropriate medical enrollment, and follow medical documentation rules. CPT is licensed by the AMA, so this wiki describes the system without reproducing the code set.

If your group bills no medical plans, you can run a large dental organization without ever touching CPT. If you do crossover billing, treat it as a separate competency: [Bill medical plans for dental work](/guides/billing/bill-medical-for-dental-work).

## The ADA Dental Claim Form

The **2024 ADA Dental Claim Form** is the paper counterpart to the 837D, much as the CMS-1500 corresponds to the 837P. It added fields for locum tenens (temporary substitute) dentist reporting, the date of last scaling and root planing, and the benefit plan Payer ID.<sup>2</sup> Even groups that submit electronically encounter the same field structure in payer portals and PMS screens.

## Taxonomy and POS

**Taxonomy codes** maintained by the NUCC identify provider type and specialty. The submitted taxonomy should match the payer enrollment record or the claim may be rejected or denied. See [Taxonomy codes](/reference/edi/taxonomy-codes).

**Place of service codes** (CMS) matter mainly on crossover claims, where facility and non-facility settings can change medical payment. See [Place of service codes](/reference/edi/place-of-service-codes).

## Annual update discipline

| Code set                               | Effective |
| -------------------------------------- | --------- |
| **CDT**                                | January 1 |
| **CPT and HCPCS Level II** (crossover) | January 1 |
| **ICD-10-CM**                          | October 1 |

The CDT 2026 cycle included 60 changes.<sup>1</sup> Before each January update, revise PMS code tables, fee schedules, scrubber edits, and any code lists in internal tools across every location. Claims must use the CDT version in effect **on the date of service**, not the submission date.

## Where each appears on a claim

| Field                          | Code set                               |
| ------------------------------ | -------------------------------------- |
| 837D `SV3` service line        | CDT (`AD` qualifier)                   |
| 837D tooth information (`TOO`) | Tooth number and surfaces              |
| 837D diagnosis segment         | ICD-10-CM, where the payer requires it |
| 837D `PRV`                     | Taxonomy                               |
| 837P `SV1` (crossover)         | CPT / HCPCS, with modifiers            |
| 837P `HI` (crossover)          | ICD-10-CM, required                    |
| 837P `CLM05` (crossover)       | Place of service                       |

## Sources

1. 45 C.F.R. § 162.1002(a)(4) ([eCFR](https://www.ecfr.gov/current/title-45/subtitle-A/subchapter-C/part-162/subpart-J/section-162.1002)); ADA News, [60 changes coming to CDT Code in 2026](https://adanews.ada.org/ada-news/2025/june/60-changes-coming-to-cdt-code-in-2026-1/); ADA, [licensing for commercial users](https://www.ada.org/publications/ada-store-products/licensing-for-commercial-users).
2. ADA, [Dental claim form](https://www.ada.org/publications/cdt/ada-dental-claim-form); [2024 completion instructions (PDF)](https://www.ada.org/-/media/project/ada-organization/ada/ada-org/files/publications/cdt/2024_completioninstructions_adaclaimform_2024.pdf); the authoritative reference for tooth numbering, surface, and oral-cavity reporting on US dental claims.