Cysts of oral region, not elsewhere classified (K09) ICD-10-CM
The K09 code range covers cysts of oral region, not elsewhere classified with 5 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Includes
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
- lesions showing histological features both of aneurysmal cyst and of another fibro-osseous lesion
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
Codes in the K09 Range 5 codes · 4 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the K09 range.
Dentigerous Cyst
Most common follicular odontogenic cyst. Occurs in relation to a partially erupted or unerupted tooth with at least the crown of the tooth to which the cyst is attached protruding into the cystic cavity. May give rise to an ameloblastoma and, in rare instances, undergo malignant transformation.
About the K09 Code Range
Cysts in the mouth area that are not classified elsewhere appear in the group for diseases of the mouth and salivary glands.
The subdivisions separate developmental odontogenic (tooth-related) cysts in K09.0 from developmental nonodontogenic cysts in K09.1. K09.8 identifies other oral-region cysts, while K09.9 identifies an oral-region cyst without a specified type.
Questions About This Page
How many billable codes are in the K09 range?
Of the 5 codes in this range, 4 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the K09 range classify?
The range classifies cysts of oral region, not elsewhere classified. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
