M27.0 classifies developmental disorders of the jaws, encompassing conditions that arise from abnormal jaw development rather than acquired disease or trauma — including latent bone cysts, Stafne's cyst, torus mandibularis, and torus palatinus.
Verified May 8, 2026 · 5 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 5
- Region
- Other
Documentation tips
What should appear in the chart to support M27.0.
Source · Editorial brief grounded in 5 cited references ↓
- Identify the specific developmental condition by name — Stafne's cyst, torus mandibularis, torus palatinus, or latent bone cyst of jaw — rather than using generic terms like 'jaw cyst' or 'jaw lesion.'
- Document imaging findings (panoramic radiograph, CBCT) that confirm developmental rather than inflammatory or neoplastic etiology — Stafne's cyst has a characteristic location below the mandibular canal on panorex.
- Note the incidental vs. symptomatic nature of the finding; tori and Stafne's cysts are frequently asymptomatic and discovered on routine imaging — document clinical relevance if coding for an active treatment encounter.
- Confirm the condition is not a manifestation of unilateral condylar hyperplasia or hypoplasia, which must be coded to M27.8, not M27.0.
- If the patient has a concurrent dentofacial anomaly or malocclusion, code those separately from M26 — M27.0 does not cover malocclusion-related developmental changes.
Related CPT procedures
Procedure codes commonly billed with M27.0. Linking the right diagnosis to the right procedure is what establishes medical necessity.
Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis
Common coding pitfalls
The recurring mistakes coders make with M27.0 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Using M27.0 for any jaw cyst without confirming developmental origin — inflammatory, odontogenic, or post-endodontic cysts belong under M27.40, M27.49, or M27.5x respectively.
- Coding unilateral condylar hyperplasia or hypoplasia to M27.0 — the tabular explicitly excludes these; use M27.8.
- Routing hemifacial atrophy or hypertrophy to M27.0 — this maps to Q67.4, a congenital anomaly code, not M27.
- Applying M27.0 when documentation only says 'jaw disorder' without specifying a developmental etiology — unspecified disease of jaws defaults to M27.9.
Clinical context
Source · Editorial summary grounded in 5 cited references ↓
M27.0 is the correct code when a clinician documents a developmentally derived jaw abnormality — specifically latent bone cyst of jaw, Stafne's cyst (a developmental cortical defect of the posterior mandible), torus mandibularis (bony protuberance on the lingual surface of the mandible), or torus palatinus (bony prominence along the midline of the hard palate). These are structural variants or anomalies present from development, not inflammatory, neoplastic, or traumatic in origin.
Do not use M27.0 for acquired or inflammatory jaw cysts — those belong under M27.40 (unspecified cyst of jaw) or M27.49 (other cysts of jaw). Unilateral condylar hyperplasia or hypoplasia is explicitly excluded from M27 and maps instead to M27.8. Hemifacial atrophy or hypertrophy routes to Q67.4. When the jaw disorder involves malocclusion or dentofacial anomalies with alveolar changes, review the M26 block before landing on M27.0.
M27.0 falls under Chapter 13 (Diseases of the Musculoskeletal System and Connective Tissue) and is a single-level billable code with no laterality or 7th-character extension required. It maps to MS-DRG groupings for dental and oral diseases (157–159) and tracheostomy for face/mouth/neck diagnoses (011–013) in inpatient settings.
Inclusion & exclusion notes
Per the official ICD-10-CM Tabular List.
Source · CDC ICD-10-CM Official Tabular List · 2026
Includes
- Latent bone cyst of jaw
- Stafne's cyst
- Torus mandibularis
- Torus palatinus
Sibling codes
Other billable codes under M27 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 5 cited references ↓
01Does M27.0 require a laterality digit or 7th-character extension?
02What is a Stafne's cyst and why does it map to M27.0?
03Should torus mandibularis and torus palatinus always be coded to M27.0?
04How does M27.0 differ from M27.40 (unspecified cyst of jaw)?
05Is M27.0 ever appropriate on an orthopedic claim, or is this purely a dental/oral surgery code?
06What ICD-10-CM codes should be checked before finalizing M27.0?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
Mira AI Scribe
Mira AI Scribe captures the lesion type (Stafne's cyst, torus mandibularis, torus palatinus, or latent bone cyst), the imaging modality and key findings confirming developmental origin, anatomical location within the jaw, and whether the finding is incidental or symptomatic. This specificity prevents downcoding to the unspecified M27.9 and avoids an audit flag from misrouting inflammatory or endodontic cysts into the developmental category.
See how Mira captures M27.0 documentation