2026 ICD-10-CM Diagnosis Code K08.431Partial loss of teeth due to caries, class I

ICD-10-CM Codes›K00–K95›K00-K14›K08

ICD-10-CM K08.431
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K08.431 is a billable ICD-10-CM diagnosis code for partial loss of teeth due to caries, class I. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 11 through 13, 157 through 159. Coders also document this condition as partial edentulism class 1. 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
K08.431
Billable Status
Yes — Valid for Submission
Code Describes
Partial loss of teeth due to caries, class I
Short Description
Partial loss of teeth due to caries, class I
Same as the full description in the CMS dataset.
Parent Code
K08.43
Partial loss of teeth due to caries

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK00-K14Diseases of oral cavity and salivary glands
CategoryK08Other disorders of teeth and supporting structures
This CodeK08.431Partial loss of teeth due to caries, class I

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Partial edentulism class 1
  • Partial edentulism class 1 due to caries
  • Partial edentulism due to caries

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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 K08.431 to ICD-9-CMHistory

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

ICD-9-CM
525.51 Part edentulism,class I
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
525.13 Loss of teeth d/t caries
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 K08.431Overview

What is the ICD-10 code for partial loss of teeth due to caries, class I?

The ICD-10-CM code for partial loss of teeth due to caries, class I is K08.431 (sometimes written as K08431). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is K08.431 (Partial loss of teeth due to caries) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report partial loss of teeth due to caries, class I on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K08.431 group to?

When partial loss of teeth due to caries, class I is the principal diagnosis on an inpatient stay, it groups to MS-DRG 11, 12, 13, 157, 158, 159, with relative weights from 0.7085 to 5.4541 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K08.431?

Under the General Equivalence Mappings, partial loss of teeth due to caries, class I converts to ICD-9-CM 525.51 (part edentulism,class I) and 525.13 (loss of teeth d/t caries). The mapping is approximate, so confirm the match fits the documentation.