Cysts of oral region, not elsewhere classified (K09)
The ICD-10 code K09 covers various types of cysts in the oral region that are not classified elsewhere, including specific developmental and other oral cysts. These codes are used to document and classify cysts found in and around the mouth, aiding accurate diagnosis and treatment planning.
The section includes K09.0 for developmental odontogenic cysts, which are cysts originating from tooth-forming tissues. These are also known by terms like odontogenic cyst, dentigerous cyst, eruption cyst of the jaw, and odontogenic keratocyst, helping medical coders identify precise conditions. The code K09.1 captures developmental nonodontogenic cysts such as naso-palatine duct cysts and palatal cysts of newborns, which arise from developmental tissues unrelated to tooth structures. K09.8 is assigned for other less common or unspecified cysts like gingival cysts of adults, lymphoepithelial cysts, and epidermoid cysts of the oral soft tissue. When the cyst type is not identified, K09.9 is used for unspecified oral cysts, sometimes simply referred to as oral cysts. These codes help healthcare providers and coders classify oral cysts accurately based on their origin and characteristics, ensuring proper documentation in medical records.
Instructional Notations
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.
Clinical Terms
The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.
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.
