Frequent General Questions Regarding Dental Procedure Codes

When it comes to the Code on Dental Procedures and Nomenclature, better known as the CDT Code, most dentists have similar questions about this ADA intellectual property. The questions (and answers) below, compiled by the ADA Practice Institute, are often asked by ADA members who seek a general understanding of the CDT Code, and who are interested in how their own unique questions can be addressed.

ADA has also developed a comprehensive reference library with coding educational material for dentists. Here you will find videos, webinars and PDF guides that provide an in-depth look, as well as focused questions and answers, on specific services that are documented and reported with their own unique CDT Codes. These items are found on the ADA’s Coding Education web pages.

The ADA also publishes coding information in print and e-book form that is available for purchase through the ADA Store. These publications are:

1. Why is the CDT Code updated annually?

Annual updates enable the CDT Code to accommodate new and evolutionary changes to dental procedures, as well as increasingly robust patient record-keeping. As the named HIPAA national standard for documenting dental procedures the ADA is also obligated to maintain an annual review and maintenance process.

2. Who requests CDT Code additions, revisions or other changes?

You do — Dentists, as primary providers of dental care, are an important source of requests for additions and revisions. Requests also come from the ADA’s Council on Dental Benefit Programs, dental specialty organizations, third-party payers, and others in the dental community. The maintenance process is open to anyone who is interested in requesting a CDT Code change.
Information about requesting a change, and other aspects of the CDT Code maintenance process is available online at Request to Change to the Code | American Dental Association ( Please review the request form completion instructions and evaluation criteria before completing and submitting the required forms.

3. How do I know which CDT Code is appropriate to document the service I delivered?

A dentist’s clinical decisions determine what services (procedures) are delivered to a patient. The full CDT Code entry as published in the current CDT manual must be considered when determining which dental procedure code should be used to document services provided. A procedure code entry consists of the code and its nomenclature that are printed in boldface type; some procedure code entries also have their own unique descriptors, printed in regular typeface. Also, some code categories or subcategories have descriptors applicable to codes within that category.

A careful reading of the complete code entry should provide the information needed for a dentist to decide which code most accurately describes the procedure that was performed. Codes should not be chosen based on what will gain the most reimbursement.

4. Why is there no CDT Code for the procedure I am providing today?

There are times when, in the opinion of the dentist, no CDT Code entry accurately describes the service provided. This is when an "unspecified …procedure by report" code may be considered (e.g., D2999 unspecified restorative procedure, by report). All "by report" procedure codes must include documentation that explains the service provided. In addition, this is an opportunity for you to submit a CDT Code action request to fill the CDT Code gap you discovered.

5. Who do I call for more information about the CDT Code or claim submission?

CDT Coding assistance is available to all ADA members, plus any non-member who has purchased the current manual. Coding matters are forwarded to the Center for Dental Benefits, Coding and Quality staff, who are within the Practice Institute. Contact the ADA Member Service Center (MSC) at 800.621.8099 or via e-mail at

6. What other CDT Code information is online?

There are webinar recordings and guides to specific procedures and their CDT codes that may be viewed online or downloaded at no cost from the Coding Education web pages. Topics and codes covered include case management services, scaling in the presence of gingival inflammation, teledentistry events, and more.

7. Why don't third-party payers cover all CDT Code procedures?

The CDT Code is a taxonomy that enables codified documentation of services provided. A dental benefit plan reflects the purchaser’s decision on what services will be covered for the plan’s cost. A dental benefit plan’s coverage limitations and exclusions provisions identify those procedures reportable with a valid CDT code that may not be covered.

Covered procedures vary between dental benefit plans, even those offered by the same third-party payer, especially those that are considered cosmetic (e.g., tooth bleaching). This is why it is important to verify the patient’s available benefits, and potential patient out-of-pocket costs, when treatment planning.

8. Doesn't HIPAA require a third-party payer to cover every procedure code listed on a claim submission?

No, HIPAA's administrative simplification provisions are limited to standards for information exchange between the sender (e.g., a dentist/practitioner; provider) and the recipient (e.g., dental benefit plan / aka third-party payer). HIPAA says that information must be exchanged in a standard format and use specific code taxonomies, which includes the CDT Code. HIPAA's administrative simplification provisions do not determine what you do within your practice, or what a payer does in its individual claim adjudication policies.

9. Why isn't the CDT Code available at no cost to members?

The Code on Dental Procedures and Nomenclature is important and valuable ADA intellectual property, and it has significant maintenance costs. Volunteer leadership views non-dues revenue from CDT publication sales and licensing as a means to offset a portion of the maintenance cost.

10. Why do I need a CDT Manual when my practice management system vendor sends a procedure code update as part of my maintenance package?

The CDT Manual includes information that is often omitted in software updates – especially the complete nomenclatures and descriptors applicable to every CDT Code entry. Practice management systems routinely truncate this information which makes choosing the correct code more difficult.

11. What is the relationship between the CDT Code and SNODENT?

These code sets each have a different purpose. The CDT Code is the HIPAA standard for codified documentation and reporting of dental procedures. On the other hand, SNODENT (Systematized Nomenclature for Dentistry) is not a HIPAA standard and may not be reported on a dental claim, but does support a codified description of the patient's condition (e.g., diagnoses and findings) and other factors that may affect treatment. The CDT Code and SNODENT do overlap in one area – both are recognized by federal agencies as code taxonomies to be used on Electronic Health Records of dental patients.

12. What is the relationship between the CDT Code and ICD Codes?

Both the CDT Code and ICD Codes are HIPAA standards applicable to electronic dental claims. ICD (International Classification of Diseases – 10th Edition – Clinical Modification) is the only diagnosis code set that may be used on claims submitted to dental benefit plans when needed, as well as on claims for dental services submitted to medical benefit plans where diagnosis codes are always required. The CDT Code is maintained by the ADA Council on Dental Benefit Programs’ Code Maintenance Committee, and ICD Codes are maintained by agencies of the federal government.

Information and guidance on reporting ICD codes with CDT codes is included in the ADA publications Current Dental Terminology and CDT Companion: Training Guide for the Dental Team that are available at the ADA Store.

13. I've received an Explanation of Benefits that shows reimbursement either for fewer services, or for different procedure codes, than those reported on the claim. How can this happen? Isn't the third-party payer doing something wrong or illegal? It looks like the CDT Code is being misused.

An explanation of benefits that shows reimbursement for fewer services or for different procedure codes than reported on the claim raises eyebrows and prompts dentists to call the ADA and ask these questions. What may be perceived as a payer’s code misuse or illegal action is likely neither, but rather a result of the dental benefit plan’s coverage provisions, and provisions of a participating provider agreement in effect on the date of service.

Many patients and some dentists do not fully understand how dental benefit programs work, and that coverage limitations and exclusions may limit reimbursement for necessary care that is correctly reported with the appropriate CDT code(s). Such a misunderstanding is compounded when EOB language suggests that the dentist is at fault. Ensuring patients understand the limitations of their dental plan prior to treatment may help avoid problems and maintain a strong dentist-patient relationship.

Some dental claim adjudication practices are appropriate when based on plan design and should be clearly explained on the EOB to prevent misunderstandings. Other situations, where the EOB message suggests the dentist is in error, may pose problems. Each of these conditions is illustrated in the following examples:

  • Acceptable EOB Explanation: A claim for a “D4355 full mouth debridement…” and a two-surface restoration is adjudicated and only the D4355 is reimbursed. The EOB message states that the benefit plan has limitations and exclusions, one of which is that the plan does not cover any restorative procedure delivered on the same day as a D4355. In this example the payer has not paid for the procedure due to benefit plan design limitations – there is no suggestion that the dentist has done anything improper.
  • Unacceptable EOB Explanation: The dentist reports a D1110 on the claim because the patient is 13 years old with predominantly adult dentition, but the EOB lists D1120 with a message that this is the correct code for a patient under the age of 15. In this example the payer is wrong, as the message implies that the dentist reported the incorrect prophylaxis procedure code. Here the payer ignored the CDT Code’s descriptor where dentition, not age, is the criterion for reporting an adult versus child prophylaxis. What the payer should do when the benefit plan specifies an age-based benefit limitation, is accept the claim as submitted and note on the EOB that the claim has been adjudicated based on benefit plan design.

The second example illustrates why it is important that the dental office help the patient understand the clinical basis for treatment. In this case the type of prophylaxis is determined by the state of the patient’s dentition, not age, even though the patient’s benefit may be determined by age.

Note: Every dentist should be aware of the following guidance when preparing a claim and reviewing an EOB.

  • The Health Insurance Portability and Accountability Act (HIPAA) requires the procedure code reported on a claim be from the CDT Code version that is effective on the date of service.
  • Neither HIPAA nor ADA policy, or the CDT Code itself require that a third-party payer cover every listed dental procedure. Covered dental procedures are identified in the contract between the plan purchaser and the third-party payer.
  • Procedure code bundling is frowned upon by the ADA. However, dentists who have signed participating provider agreements with third-party payers may be bound to plan provisions that limit or exclude coverage for concurrent procedures.

14. The insurance company has denied a claim for procedure code D4212 (gingivectomy or gingivoplasty, to allow access for restorative procedure, per tooth), saying that it is always an integral part of the restorative procedure submitted on the claim. Doesn't this look like the company is violating its CDT license by redefining the codes?

A D4212 and a restorative procedure are separate and distinct clinical services. The insurance company may not redefine either one or both. If however, the dental benefit plan does not provide a benefit for D4212, the denial must state that there is no reimbursement due to benefit plan limitations and exclusions. The payer should not disallow this procedure based on bundling.

Accurate patient record-keeping requires that all services delivered to a patient be fully documented. An insurance company's adjudication policies are completely separate matters. If you experience this type of situation, please contact ADA.

15. What fee can I charge for procedures reported with CDT codes?

The Code on Dental Procedures and Nomenclature (CDT Code) provides dentists a means to consistently document services delivered to the patient. There is no fee information in the CDT Code.

Note: Every dentist should be aware of the following guidance regarding fees for services.

  • Neither the ADA nor the CDT Code establish fee schedules for the listed procedures.
  • A dentist individually determines her or his full fee for any procedure delivered and reported with a CDT code.
  • The dentist’s full fee for a service is reported on a claim
  • Third-party payer reimbursement is determined by provisions of the dental benefit plan or applicable participating provider contract.
  • The payer’s reimbursement amount may not be the same as the dentist’s full fee for the procedures listed on a claim.