The short version
# D3330 Dental Code: Molar Endodontic Therapy
D3330 reports completed root canal therapy on a molar. The code covers treatment of the molar canal system, necessary visits, and intraoperative radiographs, but not the final coronal restoration. A claim can stall when the postoperative image misses an apex or the office bills before completion.
- Bill D3330 after endodontic therapy is completed on a molar.
- D3310 is for an anterior tooth and D3320 is for a premolar. Select from tooth class, not the number of canals found.
- The base therapy includes the appointments, clinical procedures, follow-up care, and intraoperative radiographs needed for completion.
- The final filling, core, or crown isn't included in D3330.
- Delta requires preoperative and postoperative periapical images that show the complete tooth for its D3330 claims.
- In a worked PPO claim, a $1,600 fee becomes a $1,150 allowable. The plan pays $920 at 80%, the patient owes $230, and the office adjusts $450.
What is D3330?
D3330 is primary endodontic therapy for a molar. It includes complete pulpectomy and treatment of the canal system through obturation. The AAE's guide places all necessary treatment appointments and working images inside the therapy code.
| Fact | D3330 |
|---|---|
| CDT category | Endodontics |
| Tooth class | Molar |
| Claim point | Completed therapy |
| Final coronal restoration | Excluded |
| Public fee references | Oregon Medicaid: $670.58; Washington Medicaid: $543.11 in 2025 |
When do you bill D3330?
Report D3330 when molar therapy is finished.
- Confirm the tooth number and molar status.
- Record canals located, working lengths, instrumentation, irrigation, and obturation.
- Take a postoperative image that includes the full roots and apices.
- Record the coronal seal and restoration plan.
D3330 vs D3310 and D3320
Completed primary therapy is sorted by the treated tooth.
| D3310 | D3320 | D3330 | |
|---|---|---|---|
| Tooth | Anterior | Premolar | Molar |
| Includes intraoperative images | Yes | Yes | Yes |
| Excludes final restoration | Yes | Yes | Yes |
| Oregon Medicaid example | $454.05 | $526.76 | $670.58 |
What does insurance actually do with D3330?
Delta's public submission guide asks for preoperative and postoperative periapical radiographs with completed D3310 through D3330 claims. It warns that an image that doesn't show the entire tooth can prevent benefit determination.
- Office fee: $1,600
- Contracted allowable: $1,150
- Contractual adjustment: $450
- Plan payment at 80%: $920
- Patient balance: $230
Why does D3330 get denied?
- The required preoperative and postoperative images aren't attached.
- The postoperative image doesn't show every root apex.
- The tooth isn't a molar.
- Treatment wasn't complete on the reported date.
- The plan doesn't have benefit left under the annual maximum.
What documentation gets D3330 paid?
- Don't omit the molar tooth number or endodontic diagnoses.
- Attach full-tooth preoperative and postoperative periapical images.
- List canals treated and obturation completion.
- Record the final-restoration plan.
- Verify prior root canal and retreatment history.
Common questions about D3330
Does D3330 include a core buildup?
No. D3330 reports completed molar endodontic treatment, not a core buildup. The D2950 guide explains when missing tooth structure supports that separate procedure. Document and report the buildup only when the dentist performs it and the remaining structure meets the requirements.
Are postoperative radiographs part of D3330?
The AAE says intraoperative imaging is included. Georgia Medicaid's manual also includes postoperative X-rays in its root-canal reimbursement. Keep those images with the endodontic record, but don't add a separate radiograph line when the applicable policy treats the view as part of therapy.
Can D3330 be billed at the first visit?
Only if the molar therapy is completed that day. Otherwise, document the treatment stage and report the completed services that actually occurred. File D3330 when the molar root canal procedure is finished, using the completion date supported by the clinical record.
Does canal count change D3330 to D3320?
No. Tooth class decides between molar and premolar therapy. D3330 applies to a molar even when its canal anatomy is unusual, while D3320 applies to a premolar. Record the tooth number and every canal treated, but don't choose between the codes by canal count.
Submit the complete molar record
Before filing, match the molar, completion note, and full-apex image.
Sources
- AAE, Endodontists' Guide to CDT 2026
- AAE, Endodontists' Guide to CDT 2024
- AAE, Guide to CDT endodontic therapy
- Delta Dental, endodontic X-ray submission guide
- Washington Medicaid, July 2025 dental fee schedule
- Oregon Medicaid, June 2025 fee schedule
- Georgia Medicaid, 2025 dental manual and fee material
- AAE, dental insurance FAQ
CDT codes and nomenclature are copyright © American Dental Association. This guide explains the code in plain language; the current CDT manual is the authoritative source.
