ICD-10 Code K09.1 – Developmental (nonodontogenic) cysts of oral region (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K09.1 – Developmental (nonodontogenic) cysts of oral region
What it is
K09.1 identifies developmental cysts in the oral region that are not related to tooth formation. Use it for congenital or developmental cystic lesions arising in oral tissues when documentation supports a nonodontogenic origin.
Clinical signs
These cysts are often found as a painless swelling, incidental radiographic lesion, or slowly enlarging oral mass. Clinical features vary; refer to documentation and pathology when available.
When to use this code
Use K09.1 when the provider documents a developmental, nonodontogenic cyst of the mouth, jaw, or oral region. It fits cases confirmed by imaging, examination, or surgical/pathology reports. If the record only says “oral cyst” without type, check documentation before coding.
Do not use for
Do not use this code for odontogenic cysts, periapical cysts, or inflammatory dental lesions. If the lesion is described as an abscess, tumor, or unspecified cyst without developmental origin, check documentation.
Coding tip
Code K09.1 only when the record clearly states nonodontogenic developmental origin; otherwise, query for specificity.