There is no CDT code hard reline entry in the code set, which is exactly why the search exists. The manual does not sort relines by material. It sorts them by three other things: which arch, whether the prosthesis is complete or partial, and whether the work was done at the chair or sent to a laboratory. A hard reline is reported with whichever of the eight reline codes matches those three facts. Soft liners sit in their own block.
One question becomes three, and getting any of the three wrong produces a line the plan reprices, bundles or rejects.
The eight reline codes, in one grid
Pick the row by what you are relining, the column by where the material was processed.
| Prosthesis and arch | Direct, at the chair | Indirect, at the lab |
|---|---|---|
| Complete denture, maxillary | D5730 | D5750 |
| Complete denture, mandibular | D5731 | D5751 |
| Partial denture, maxillary | D5740 | D5760 |
| Partial denture, mandibular | D5741 | D5761 |
Three things about this grid.
The wording on your fee schedule is older than the manual. Payer portals and practice management systems still print chairside and laboratory. Current CDT nomenclature reads direct and indirect. Same numbers, so do not hunt for a new code when the two disagree on the word.
Nothing in these eight codes says hard or soft. The code follows the arch and the technique, not the acrylic. A resilient soft liner is a separate procedure with its own code.
Arches are separate lines. A patient relined top and bottom in one visit is two lines, D5750 and D5751 for complete dentures in the lab, not one line at a quantity of two.
What does the dental code D5750 represent?
D5750 is the indirect reline of a complete maxillary denture. The denture is impressed, sent to the laboratory, and new base material is processed against the current shape of the ridge. The patient is without it for the turnaround, which is the part the front desk has to explain.
It carries a higher fee and a higher allowable than D5730, because laboratory processing is inside the fee. That gap is where the common error lives: the office relines at the chair, then bills the laboratory code because that is the one in the favorites list. The reverse quietly underbills a lab case.
Settle as a team which date of service you report when the impression and the insertion fall on different days, because a date landing a week inside an exclusion window turns a paid line into a denied one.
Reline, rebase, soft liner: three procedures, three code blocks
These get used interchangeably at the front desk. They are not interchangeable on a claim.
| Procedure | What actually changes | Codes |
|---|---|---|
| Reline | New material is added to the tissue surface of the existing base | D5730, D5731, D5740, D5741 direct; D5750, D5751, D5760, D5761 indirect |
| Rebase | The entire denture base is replaced, the existing teeth are retained | D5710 and D5711 complete, upper and lower; D5720 and D5721 partial, upper and lower |
| Soft liner | A resilient liner is placed in a complete or partial removable denture | Separate soft liner codes, including D5765 for the indirect version |
Nomenclature is abbreviated here. Confirm each against the current CDT manual before loading it into your fee schedule, because the ADA's Code Maintenance Committee revises entries annually and the D5000 series sees more revision than most.
A rebase is the bigger procedure and the bigger fee, so reporting one as a reline gives away the difference every time. Reporting a reline as a rebase invites a records request and burns a benefit the patient may need later. Our guide to the differences between CDT and CPT codes in dentistry explains why the block a code sits in changes how a claim is read.
What does the dental code D5422 represent?
D5422 is adjust partial denture, mandibular. The set runs D5410 and D5411 for adjusting a complete denture, upper and lower, and D5421 and D5422 for adjusting a partial.
It belongs here because the two get swapped in both directions. A sore spot relieved with a bur is an adjustment. New base material added to the intaglio surface is a reline. Billing a reline for a five minute adjustment is a coding problem with your name on it. Billing an adjustment for an hour of chairside relining is a revenue problem with nobody's name on it, which is why it survives longer.
Expect a bundling rule too: an adjustment on the same arch and date as a reline is commonly treated as part of the reline and denied as inclusive. That is a bundling denial, not a coverage denial, and the two carry different codes on the remittance. Our reference on CARC, RARC and CAGC codes maps which is which, and the patterns in why bone graft claims get denied repeat here.
What does the CDT code D5875 represent?
D5875 is modification of a removable prosthesis following implant surgery. The existing denture is relieved over cover screws or healing abutments so the patient can wear it without loading the fixtures. It is not a reline, and it is reported once per prosthesis, not once per implant.
It lands in reline searches because both happen to the same denture, weeks apart. The modification is the day of or just after surgery. The reline comes later, once tissue has settled, on its own date with its own code from the grid above. Two procedures, two dates, two lines.
What is dental code D0431?
D0431 is the adjunctive pre-diagnostic test that aids in detection of mucosal abnormalities including premalignant and malignant lesions, not to include cytology or biopsy procedures. It is not a reline code. It turns up in these searches because the reline visit is one of the few times the prosthesis is out and the tissue under it is visible, and long term denture wearers carry chronic irritation. D0431 is an adjunct to that examination, not a substitute. Coverage is limited on many plans and excluded on others, so it is a verification question, and the patient should hear the cost beforehand.
Frequency is what actually decides the claim
The code is the easy part. What denies a correctly coded reline is frequency, and that provision is chosen by the employer group rather than the carrier, so it varies plan to plan inside one carrier's book. Below are commonly quoted ranges: treat them as what to ask about, not what the plan says.
| Provision | Commonly quoted | What to ask, by arch |
|---|---|---|
| Reline frequency | Once per arch in a 24 to 36 month window | When was the last reline paid, and on which arch |
| Exclusion after delivery | No reline within about 6 months of the denture being delivered | What delivery date is on file for the prosthesis |
| Benefit category | Major services on most plans | Basic or major, and at what percentage |
| Waiting period | 6 to 12 months on major services | Is there one, and does prior coverage credit against it |
That second row catches the most practices, because the plan's stored delivery date is not always the one you would guess. It can come from a prior carrier, a prior office, or a denture the plan never paid for. Ask for the date the plan holds, not the date in your chart.
An immediate denture makes this sharper. Tissue remodels fast after extractions, so a reline in the first year is routine, and that is exactly the window where plans call it included in the denture fee. There, a predetermination beats an appeal, and the mechanics match our walkthrough of how to get a predetermination approved.
The arithmetic on a lower lab reline, with illustrative numbers.
| Line | Amount |
|---|---|
| Office fee, D5751 | 385 |
| Contracted allowable | 260 |
| Contractual write off, 385 minus 260 | 125 |
| Plan pays at 50 percent of 260 | 130 |
| Patient responsibility | 130 |
Run the same case inside the post-delivery exclusion and the plan pays nothing. What the patient owes then depends on your participating provider agreement and on state law, because some contracts hold you to the contracted rate on a non-covered service and some do not. Read your agreement, and confirm with your state insurance department, since non-covered service provisions are legislated state by state and keep changing as of this writing.
What to put on the claim
A bare reline line looks like small maintenance and gets adjudicated like it. Send context with it.
- The arch and the prosthesis, stated in the narrative even though the code names them.
- The delivery date of the denture or partial, and whether your office delivered it.
- Why the reline is needed now: ridge resorption, post-extraction remodeling, or a post-surgical change.
- The material, hard or soft, since no reline code carries that distinction.
- The laboratory invoice when the plan asks for it.
- Nothing bundled in. An adjustment, a repair or a tissue conditioning material each has its own code and date.
Where the prosthesis is part of rehabilitation after trauma or a tumor resection, part of the case may belong on a medical claim, and medical carriers expect different documentation. Our guides to cross coding and medical billing for TMJ treatment cover what they look for.
The reline is a small fee. It earns this much attention because four questions decide every removable prosthodontic claim you file: which arch, which technique, what the plan has on file, and what the last one consumed. Curo reads prosthodontic limits and stored history at verification and flags what will deny before the appointment is booked, the work on our denial management page.
If you change one thing here, make it the delivery date. Put a field for it in your denture chart notes, ask the plan for its version at every reline verification, and the six month denials stop being surprises.