ICD-10-CM 2027
ICD-10 code for apical cyst
From the official ICD-10-CM alphabetic index entry “Cyst (colloid) (mucous) (simple) (retention) › apical (tooth) (periodontal)”. Page updated September 29, 2026.
About coding apical cyst
The ICD-10-CM code for apical cyst is K04.8 (Radicular cyst).
Within K04 (diseases of pulp and periapical tissues), K04.8 is specifically for Radicular cyst. Related codes cover pulpitis (K04.0), necrosis of pulp (K04.1), pulp degeneration (K04.2), abnormal hard tissue formation in pulp (K04.3), acute apical periodontitis of pulpal origin (K04.4), chronic apical periodontitis (K04.5), periapical abscess with sinus (K04.6), periapical abscess without sinus (K04.7) and 1 more.
The conditions in its Excludes2 note aren't part of K04.8, but may be coded alongside it if the patient has both: lateral periodontal cyst (K09.0).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about apical cyst ICD-10 codes
What is the ICD-10 code for apical cyst?
- K04.8 — Radicular cyst.
Is K04.8 billable?
- Yes. K04.8 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K04.8 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K04.8 as a principal diagnosis.
Is K04.8 a CC or MCC?
- No. K04.8 is neither a CC nor an MCC under MS-DRG v44.0.