ICD-9-CM diagnosis code (retired)
524.21 — Malocclusion, Angle's class I
ICD-9-CM was replaced by ICD-10 on October 1, 2015. These are the ICD-10-CM equivalents from the CMS General Equivalence Mappings.
About ICD-9-CM 524.21
524.21 is an ICD-9-CM diagnosis code for malocclusion, Angle's class I. ICD-9-CM was retired for U.S. claims on October 1, 2015, when ICD-10-CM took over.
The CMS General Equivalence Mappings translate it to one ICD-10-CM code, M26.211 (Malocclusion, Angle's class I). The match is exact.
ICD-10-CM equivalents
- M26.211Malocclusion, Angle's class Iexact match
Common questions about 524.21
What is the ICD-10 code for ICD-9 524.21?
- The GEMs map 524.21 to ICD-10-CM M26.211.
GEMs are a translation aid, not a substitute for coding from the record. The 2027 ICD-10 code set has changed since the last GEMs release in 2018. Page updated September 29, 2026.