2026 ICD-10-CM Diagnosis Code K04.90Unspecified diseases of pulp and periapical tissues
ICD-10-CM Codes›K00–K95›K00-K14›K04
- Billable — Valid for Submission
- Not Chronic
K04.90 is a billable ICD-10-CM diagnosis code for unspecified diseases of pulp and periapical tissues. 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 disorder of periapical tissues of tooth. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Any dental condition including traumatic injury, Disorders of teeth and gingiva, and Nontraumatic dental conditions.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Disorder of periapical tissues of tooth
- Disorder of pulp of tooth
- Maxillary sinusitis due to dental disorder
- Maxillary sinusitis due to endodontic disease
- Posteruptive color change of tooth
- Posteruptive tooth staining due to pulpal bleeding
- Pulp and periapical tissue disease
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Disease, diseased - See Also: Syndrome;
- periapical tissues NOS - K04.90
- pulp (dental) NOS - K04.90
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Disease, diseased
- periapical tissues NOS
- Disease, diseased
- pulp (dental) NOS
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Gum Disease
If you have gum disease, you're not alone. Many U.S. adults currently have some form of the disease. It ranges from simple gum inflammation, called gingivitis, to serious damage to the tissue and bone supporting the teeth. In the worst cases, you can lose teeth.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert K04.90 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K04.90Overview
Is K04.90 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified diseases of pulp and periapical tissues on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does K04.90 group to?
When unspecified diseases of pulp and periapical tissues 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 K04.90?
Under the General Equivalence Mappings, unspecified diseases of pulp and periapical tissues converts to ICD-9-CM 522.9 (pulp/periapical dis NEC). 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.
