Augmentation of the mandible using a bone graft, typically to build up deficient jaw volume for reconstructive purposes.
Verified May 8, 2026 · 5 sources ↓
- Medicare
- $3,968.03
- Total RVUs
- 118.8
- Global, days
- 90
- Region
- Other
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 5 cited references ↓
- Operative note must identify graft type (autograft, allograft, or synthetic) and harvest site if autogenous
- Clearly document the clinical indication — congenital deficiency, post-traumatic atrophy, post-resection reconstruction, or other reconstructive basis
- Distinguish procedure from CPT 21125 (prosthetic augmentation) and CPT 21215 (iliac graft) by specifying graft source and recipient site anatomy in the note
- Pre-operative imaging (panoramic radiograph, CT, or CBCT) documenting the mandibular deficiency and planned reconstruction
- Medical necessity narrative establishing functional impairment where payer requires reconstructive vs. cosmetic distinction
- If a separate donor-site procedure is performed, document that harvest in a distinct operative note section to support separate coding
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 5 cited references ↓
CPT 21127 covers surgical augmentation of the mandible using a bone graft — most commonly autogenous bone harvested from a donor site, though allograft material may also be used. The procedure addresses volumetric deficiency of the lower jaw caused by congenital anomaly, trauma sequelae, atrophy, or prior resection. It is distinct from CPT 21125 (mandibular body augmentation with prosthetic material) and CPT 21215 (iliac bone graft to the mandible), so operative documentation must clearly distinguish the graft source and recipient site anatomy.
The 090-day global period means all routine postoperative care — wound checks, suture removal, and minor complications — is bundled into the surgical payment through day 90. Unrelated E/M visits during that window require modifier 24. Staged or planned secondary procedures within the global require modifier 58; unplanned returns to the OR for a related complication use modifier 78.
This code is billed almost exclusively by oral and maxillofacial surgeons and dentists with surgical privileges. Medicare coverage is not automatic — payers scrutinize whether the indication is reconstructive (covered) versus cosmetic (not covered). CMS guidance under LCD L35090 governs the cosmetic-versus-reconstructive distinction, and documentation must establish functional impairment or clear reconstructive need to support medical necessity.
RVU & reimbursement
Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.
Source · CMS Physician Fee Schedule, RVU26A · January 2026
| Work RVU | 12.13 |
| Practice expense RVU | 105.28 |
| Malpractice RVU | 1.39 |
| Total RVU | 118.8 |
| Medicare national rate | $3,968.03 |
| Global period | 90 days |
Payment by site of service
Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.
Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026
| Setting | Medicare rate (national) |
|---|---|
Office (PFS non-facility) Procedure performed in physician's office | $3,968.03 |
HOPD (APC 5165) Hospital outpatient department | $6,048.05 |
ASC (PI P2) Ambulatory surgical center (freestanding) | $3,025.62 |
Common denial reasons
The recurring reasons claims for CPT 21127 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Cosmetic exclusion applied when documentation fails to establish functional impairment or reconstructive medical necessity
- Upcoding or miscoding when graft source is not clearly documented, causing confusion with CPT 21125 or 21215
- Missing or inadequate pre-operative imaging to support the extent of mandibular deficiency documented
- Global period conflicts when postoperative E/M visits are billed without modifier 24 for unrelated conditions
- Bundling denial when bone harvest (e.g., CPT 20900 series) is billed separately without documentation supporting a distinct procedure
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 5 cited references ↓
01How does CPT 21127 differ from CPT 21125 and CPT 21215?
02Can the bone harvest procedure be billed separately with 21127?
03Does Medicare routinely cover CPT 21127?
04What modifier applies if a complication requires a return to the OR during the 90-day global?
05Is modifier 22 appropriate for an unusually complex augmentation?
06Which site of service pays more — HOPD or ASC?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CMS Physician Fee Schedule 2026
- 02cms.govhttps://www.cms.gov/medicare-coverage-database/view/article.aspx?articleid=56658&ver=38&
- 03cms.govhttps://www.cms.gov/medicare-coverage-database/view/article.aspx?articleid=56587&ver=43&
- 04cms.govhttps://www.cms.gov/files/document/04-chapter4-ncci-medicare-policy-manual-2025finalcleanpdf.pdf
- 05cgsmedicare.comhttps://www.cgsmedicare.com/medicare_dynamic/j15/partb/ptpb/ptp.aspx
Mira AI Scribe
Mira's AI scribe captures graft type, harvest site, recipient site anatomy, and the reconstructive indication directly from surgeon dictation. It flags operative notes that lack explicit graft source documentation or omit the functional impairment rationale — the two most common triggers for cosmetic-exclusion denials and code-specificity audits on mandibular augmentation claims.
See how Mira captures CPT 21127 documentation