ICD-10-CM 2027 diagnosis code
M26.220Open anterior occlusal relationship
M26.220 is a valid, billable ICD-10-CM code for open anterior occlusal relationship. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Looking up by condition? See ICD-10 code for Antero-occlusion.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About M26.220
M26.220 is the ICD-10-CM diagnosis code for open anterior occlusal relationship. It belongs to category M26 (dentofacial anomalies [including malocclusion]), block M26-M27 (dentofacial anomalies [including malocclusion] and other disorders of jaw) and chapter 13 (diseases of the musculoskeletal system and connective tissue). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within M26.22 (open occlusal relationship), M26.220 is specifically for open anterior occlusal relationship. Related codes cover posterior occlusal relationship (M26.221).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC, relative weight 5.6154), DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC, relative weight 4.381), DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC, relative weight 2.7307), DRG 157 (Dental and Oral Diseases with MCC, relative weight 1.809), DRG 158 (Dental and Oral Diseases with CC, relative weight 0.9366) and DRG 159 (Dental and Oral Diseases without CC/MCC, relative weight 0.6893), in Pre-MDC and MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth and Throat), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 524.24 (open anterior occlusal relationship).
Coding notes
- Anterior open bite
Notes that apply from higher levels
Instructions written at a parent level also apply to M26.220.
Broader instructions also apply from M26-M27 Dentofacial anomalies [including malocclusion] and other disorders of jaw and Chapter 13: Diseases of the musculoskeletal system and connective tissue.
Alphabetic index entries
3 entriesTerms in the official ICD-10-CM index that lead to M26.220.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC PRE · Pre-MDC
MDC 03 · Diseases and Disorders of the Ear, Nose, Mouth and Throat
ICD-9-CM equivalent
Converter →- 524.24Open anterior occlusal relationshipexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about M26.220
Is M26.220 billable?
- Yes. M26.220 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M26.220 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M26.220 as a principal diagnosis.
Is M26.220 a CC or MCC?
- No. M26.220 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does M26.220 group to?
- M26.220 is used in the MS-DRG v44.0 logic for MS-DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC), MS-DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC), MS-DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC), MS-DRG 157 (Dental and Oral Diseases with MCC), MS-DRG 158 (Dental and Oral Diseases with CC) and MS-DRG 159 (Dental and Oral Diseases without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for M26.220?
- The CMS General Equivalence Mappings map M26.220 to ICD-9-CM 524.24.