2026 ICD-10-CM Diagnosis Code K02.61Dental caries on smooth surface limited to enamel

ICD-10-CM Codes›K00–K95›K00-K14›K02

ICD-10-CM K02.61
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K02.61 is a billable ICD-10-CM diagnosis code for dental caries on smooth surface limited to enamel. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 157 through 159. Coders also document this condition as caries of smooth surface of tooth. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Any dental condition including traumatic injury; Caries, periodontitis, and other preventable dental conditions; and Disorders of teeth and gingiva.

Code Identity

ICD-10-CM Code
K02.61
Billable Status
Yes — Valid for Submission
Code Describes
Dental caries on smooth surface limited to enamel
Short Description
Dental caries on smooth surface limited to enamel
Same as the full description in the CMS dataset.
Parent Code
K02.6
Dental caries on smooth surface

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK00-K14Diseases of oral cavity and salivary glands
CategoryK02Dental caries
This CodeK02.61Dental caries on smooth surface limited to enamel

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Caries of smooth surface of tooth
  • Dental caries on smooth surface limited to enamel
  • Primary dental caries, nonproximal smooth surface origin
  • Primary dental caries, proximal smooth surface origin

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • White spot lesions initial caries on smooth surface of tooth

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Caries
      • dental (dentino enamel junction) (early childhood) (of dentine) (pre-eruptive) (recurrent) (to the pulp)
        • coronal surface
          • smooth surface
            • limited to enamel
    • Caries
      • dental (dentino enamel junction) (early childhood) (of dentine) (pre-eruptive) (recurrent) (to the pulp)
        • smooth surface
          • limited to enamel
    • Caries
      • initial (tooth)
        • smooth surface
    • Lesion(s) (nontraumatic)
      • tooth, teeth
        • white spot
          • smooth surface
    • Lesion(s) (nontraumatic)
      • white spot (tooth)
        • smooth surface
    • White
      • spot lesions, teeth
        • smooth surface

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR DEN001
Any dental condition including traumatic injury
Default principal diagnosis: inpatient No · outpatient No
CCSR DEN003
Caries, periodontitis, and other preventable dental conditions
Default principal diagnosis: inpatient No · outpatient No
CCSR DIG002
Disorders of teeth and gingiva
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR DEN002
Nontraumatic dental conditions
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Tooth Decay

Tooth decay is damage to a tooth's surface, or enamel. It happens when bacteria in your mouth make acids that attack the enamel. Tooth decay can lead to cavities (dental caries), which are holes in your teeth. If tooth decay is not treated, it can cause pain, infection, and even tooth loss.

The full article covers:

  • What is tooth decay?
  • What causes tooth decay?
  • Who is at risk for tooth decay?
  • What are the symptoms of tooth decay and cavities?
  • How are tooth decay and cavities diagnosed?
  • What are the treatments for tooth decay and cavities?
  • Can tooth decay be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert K02.61 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
521.01 Dental caries - enamel
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
521.07 Dentl caries-smooth surf
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K02.61Overview

Is K02.61 (Dental caries on smooth surface) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report dental caries on smooth surface limited to enamel on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K02.61 group to?

When dental caries on smooth surface limited to enamel is the principal diagnosis on an inpatient stay, it groups to MS-DRG 157, 158, 159, with relative weights from 0.7085 to 1.7168 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K02.61?

Under the General Equivalence Mappings, dental caries on smooth surface limited to enamel converts to ICD-9-CM 521.01 (dental caries - enamel) and 521.07 (dentl caries-smooth surf). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.