Surgical · Other

Surgical removal of a benign cyst or tumor from the maxilla (upper jaw) via an intraoral approach that requires cutting through bone (osteotomy) — used for locally aggressive or destructive lesions.

Verified May 8, 2026 · 6 sources ↓

Medicare: $906.83
Total RVUs: 27.15
Global, days: 90
Region: Other

Drawn from CMSAetnaGenhealthMdclarity

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 6 cited references ↓

Preoperative imaging (CT, CBCT, or panoramic radiograph) documenting lesion size, location, and cortical bone involvement
Operative note explicitly naming the intraoral osteotomy technique and confirming bone cutting was required for access or complete removal
Pathology report confirming benign histology (required for medical-benefit coverage and post-payment audit defense)
Medical necessity statement explaining why the lesion was locally aggressive or destructive and why simple enucleation was insufficient
Documentation of any anatomic structures at risk (sinus floor, tooth roots, inferior alveolar nerve analog) that influenced surgical complexity
Anesthesia type used — general anesthesia strengthens medical-necessity argument for facility-based billing

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 50 Bilateral procedure 51 Multiple procedures 52 Reduced services 58 Staged or related 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 21048 describes an open intraoral excision of a benign cyst or tumor of the maxilla that cannot be removed by simple enucleation alone. The intraoral osteotomy — cutting through maxillary bone to access and fully extirpate the lesion — is what distinguishes this code from less complex maxillary excision codes. Typical indications include locally aggressive lesions such as keratocystic odontogenic tumors, ameloblastomas, or large dentigerous cysts that have expanded or resorbed cortical bone.

This is a 90-day global procedure. All routine post-operative management, wound checks, and suture removal through postoperative day 90 are bundled. A separate E/M or surgical service during that window requires modifier 24 (unrelated E/M) or 79 (unrelated surgical procedure). An unplanned return to the OR for a complication directly related to the original surgery uses modifier 78.

Coverage under medical (not dental) benefits hinges on medical necessity documentation. Aetna's clinical policy bulletin explicitly lists 21048 as covered when selection criteria are met — but the operative note must distinguish the complexity requiring osteotomy from simpler cyst removal. Payers routinely request pre-authorization and imaging. The site-of-service differential between HOPD and ASC is substantial; see the Site of Service comparison table for current payment figures.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	14.34
Practice expense RVU	11.05
Malpractice RVU	1.76
Total RVU	27.15
Medicare national rate	$906.83
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	$906.83
HOPD (APC 5165) Hospital outpatient department	$6,048.05
ASC (PI R2) Ambulatory surgical center (freestanding)	$3,025.62

Common denial reasons

The recurring reasons claims for CPT 21048 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Claim routed to dental benefit instead of medical benefit — requires operative note and diagnosis codes establishing medical necessity to redirect
Operative note lacks explicit mention of osteotomy, making the procedure indistinguishable from a simpler cyst enucleation (21046)
Missing or pending pathology report at time of claim submission — payers require histologic confirmation of benign nature
Prior authorization not obtained; many commercial payers require pre-auth for intraoral maxillary bone surgery
Modifier absent when billing same-day related services within the 90-day global period, triggering bundling edits

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What separates CPT 21048 from 21046?

21046 covers simple enucleation or curettage of a maxillary cyst without bone cutting. 21048 requires an intraoral osteotomy — the bone must be cut to access or fully remove the lesion. If your operative note doesn't document the osteotomy, expect downcoding to 21046.

02Should 21048 bill under the patient's dental or medical benefit?

Medical benefit. The procedure involves surgical osteotomy of the maxilla, not a routine dental extraction or restoration. Aetna, among other payers, explicitly lists 21048 as covered under medical plans when selection criteria are met. Route the claim to medical and include ICD-10 diagnosis codes that reflect the benign jaw lesion, not a dental diagnosis.

03Is modifier 50 appropriate if bilateral maxillary cysts are excised in the same session?

Yes, if lesions on both the left and right maxilla each require a separate osteotomy. Append modifier 50 and document each lesion's location and the discrete osteotomy performed for each side. Some payers prefer LT/RT on separate line items — check payer-specific rules before submitting.

04How do you handle a planned staged procedure after 21048 within the 90-day global?

Use modifier 58 for a staged or related procedure that was planned at the time of the original surgery — for example, a bone graft or reconstructive procedure scheduled at the initial encounter. Modifier 58 reopens billing within the global period for that service.

05What diagnosis codes support medical necessity for 21048?

Common supporting ICD-10 codes include D16.4 (benign neoplasm of bones of skull and face), K09.0 (developmental odontogenic cysts), and K09.1 (developmental (non-odontogenic) cysts of oral region). The specific code must match the pathology report. Submitting a generic dental caries code will trigger dental-benefit routing and likely denial.

06Can the operating surgeon separately bill for moderate sedation if they also perform 21048?

No. Per NCCI policy, a physician who performs both the surgical procedure and anesthesia (including moderate sedation) cannot separately report sedation services for the same encounter. If an independent anesthesiologist provides general anesthesia, that provider bills anesthesia codes separately under their own NPI.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the intraoral osteotomy technique by name, the lesion's aggressive or destructive behavior documented in the operative dictation, anatomic extent of bone removal, and the specific maxillary site — left, right, or bilateral. That documentation prevents downcoding to 21046 (simple cyst removal without osteotomy) and supports medical-benefit routing over dental-benefit denial.

See how Mira captures CPT 21048 documentation