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CDT codes D1354, D1355, and the new D2991: Clearing up the confusion

Sept. 12, 2023
Are you confused about the differences between the CDT codes for caries arrest (D1354) and caries prevention (D1355)? The authors clarify these and introduce a new code (D2991) coming in 2024.

What is the difference between the caries arrest code (D1354) and the caries prevention code (D1355)? Which products are best used for what?

As dental hygienists, we are the experts at providing both preventive and therapeutic procedures, so these two procedure codes fall perfectly into our wheelhouse. We are responsible for the treatment and prevention of all oral diseases, including caries.

Basic review of CDT procedure coding

Remember that, per the American Dental Association’s CDT 2023 Current Dental Terminology (page v), “the presence of a CDT code does not mean that the procedure is endorsed by any entity or is considered a standard of care,” nor does it mean that it is “covered or reimbursed by a dental benefits plan.”1

HIPAA requires use of the most accurate procedure code and coding for all procedures in electronic health records.2 This can also serve as the most accurate documentation and potential coverage under a dental insurance policy. CDT codes are not insurance codes—there is no such thing as an insurance code. CDT codes are procedure codes, and dental professionals are obligated to use the most accurate procedure code available that closely matches their procedure. There are now approximately 800 CDT procedure codes from which to choose. Dental hygiene state practice acts vary, but there are anywhere from 50 to 100 procedures hygienists can provide.

According to the ADA Principles of Ethics and Code of Conduct, “A dentist who incorrectly describes on a third-party claim form a dental procedure in order to receive a greater payment or reimbursement … is engaged in making an unethical, false or misleading representation to such third party."3 Many dental and dental hygiene practice acts include this language in their statutes and/or rules and regulations. Failing to adhere to this principle could be grounds for disciplinary action.

From “The ‘Golden Rules’ of Procedure Coding” in the CDT 2023 Coding Companion: Training Guide for the Dental Team4:

  • “Code for what you do” is the fundamental rule to apply in all coding
  • After reading the full nomenclature and descriptor, select the code that matches the procedure delivered to the patient.
  • If there is no applicable code, document the service using an unspecified, by report code “999,” and include a clear and appropriate narrative.
  • The existence of a procedure code does not mean that the procedure is covered or reimbursed in a dental benefit plan.
  • Treatment planning is based on clinical need, not covered

As of today, per the CDT 2023 Current Dental Terminology, the procedure codes read as follows:

D1354: Application of caries-arresting medication application, per tooth. Conservative treatment of an active, nonsymptomatic carious lesion by topical application of a caries-arresting or inhibiting medicament and without mechanical removal of sound tooth structure.

D1355: Caries preventive medicament application, per tooth. For primary prevention or remineralization. Medicaments applied do not include topical fluorides.

You might also be interested in: When should you use the D4346 scaling procedure code?

CDT procedure code D1354

D1354 was approved for use by the ADA Code Maintenance Committee (CMC) in CDT 2016. The only revision of this code has been in adding “per tooth” to the nomenclature, which was effective in CDT 2018.

This procedure code was originally developed when silver diamine fluoride (SDF) came to the US market and there was no appropriate procedure code for a medicament used to treat active carious lesions. However, it is important to note that SDF is currently the “typical” medicament used. As other products that arrest carious lesions enter the market, this would be the proper procedure code to use.

CDT procedure code D1355

D1355 was approved for use beginning in CDT 2021. This code was created to fill a reporting gap. There was not a procedure code for products that would prevent caries outside of fluoride products.

Some of the materials used for arresting carious lesions can also be used for primary prevention on high-risk tooth surfaces in patients of all ages. In older adults, exposed root surfaces are at risk. Deep fissured and fixed ortho-banded teeth are at risk in patients of all ages.

The materials commonly used for D1355 are silver diamine fluoride, thymol-chlorhexidine varnishes, topical povidone iodine, and silver nitrate. The only exclusions listed in the manual are topical fluorides, which are full-mouth application using D1206 or D1208 with gels, varnishes, foams, and rinses. D1355 is used when there is the absence of a carious lesion. Most of the time it is associated with a caries risk assessment of moderate or high using either procedure code D0603 or D0604.

CDT procedure code D2991 (available in CDT 2024)

A new procedure code is coming based on a new type of medicament that will take caries prevention to a whole new level: D2991: application of hydroxyapatite regeneration medicament, per tooth. Preparation of tooth surfaces and topical application of a scaffold to guide hydroxyapatite regeneration.

When these products are applied, there is regeneration of the enamel on an incipient lesion—not just arrest of the lesion but regeneration. The first product on the market was Curodont Repair Fluoride Plus by vVardis; it is distributed through Young Specialties, Patterson, BenCo, and Schein. A newer addition is CrystLCare by Greenmark. It is our understanding that there are more products in development, which is good news for our patients!

Although use of this product could eliminate the need for restorations on teeth with incipient decay, the CMC included this procedure in the restorative category. We believe it would have been more appropriate for the preventive category. Time will tell if it should be reclassified, but in the meantime, hygienists and dentists have a new tool in their toolbox for treating carious lesions.

Editor's note: This article appeared in the September 2023 print edition of RDH magazine. Dental hygienists in North America are eligible for a complimentary print subscription. Sign up here.


1. CDT 2023 Current Dental Terminology. American Dental Association; 2022.
2. Health Insurance Portability and Accountability Act of 1996 (HIPAA). Centers for Disease Control and Prevention. Reviewed June 27, 2022.
3. Principles of Ethics and Code of Professional Conduct. American Dental Association. Updated March 2023.
4. The “golden rules” of procedure coding. In: CDT 2023 Coding Companion: Training Guide for the Dental Team. American Dental Association; 2022:16.

About the Author

Kathy S. Forbes, BS, RDH

Kathy S. Forbes, BS, RDH, has been a dental hygienist, educator, speaker, author, consultant, seminar, and study club leader for more than 40 years. She holds a license with the ADA for Current Dental Terminology, which allows her to provide the most up-to-date understanding of current procedure codes. Kathy currently serves as a director for the Dental Codeology Consortium, reviewing and developing procedure codes relevant to dental hygiene practice that are presented to the Code Maintenance Committee of the American Dental Association in March each year. 

About the Author

Connie Simmons, MA, BSDH, RDH

Connie Simmons, MA, BSDH, RDH, earned her BSDH from The Ohio State University and her MA in aging studies from Wichita State University. She’s worked in clinical hygiene for almost 35 years and has other roles in clinical training, sales, speaking, and writing. Her knowledge of dental insurance and coding grew while working with an insurance carrier, and she’s now part of the Dental Codeology Consortium and an associate productivity coach with Inspired Hygiene. She’s also an expert in the clinical use of silver diamine fluoride. Reach her at [email protected].

Updated August 10, 2023