D9946 Dental Code: Partial Arch Guard Billing Guide

What D9946 covers

D9946 reports a custom-fabricated hard occlusal guard that covers only part of an arch. The most familiar example is an anterior deprogrammer or NTI-style device, a small rigid appliance seated over the front teeth that keeps the back teeth from meeting. Partial posterior coverage falls here too. The code is about the span, not the tooth position.

Like the full-arch guard codes, it takes in the impression or scan, the lab fabrication, and the delivery and fit appointment. It is a protective, parafunctional-habit appliance, which matters because the code set draws hard lines around what it is not:

• It is not a sleep apnea or anti-snoring appliance. Those are the custom sleep appliance codes, D9947 for fabrication and placement, with D9948 and D9949 for adjustment and repair.
• It is not an appliance made to treat a diagnosed temporomandibular disorder. That is generally D7880, the occlusal orthotic device reported by report, and many plans route it through a separate TMD benefit or through medical entirely.
• It is not an athletic mouthguard, which is D9941.
• It is not reshaping the natural bite. That is an occlusal adjustment, D9951 or D9952.

That last distinction between a guard and a TMD orthotic is not cosmetic. UnitedHealthcare’s dental clinical policy on occlusal guards, effective January 1 2026, indicates guards for bruxism or clenching that is wearing or fracturing teeth and restorations, and for protecting natural teeth against opposing porcelain or ceramic. The same policy says they are not indicated for treating temporomandibular disorders, for headaches or other craniofacial pain, for orthodontic tooth movement, or for sports.

Hard or soft, full arch or partial arch

Three codes replaced the old by-report guard code, D9940, in the CDT 2019 update, and they split it along two axes at once.

Material	Full arch	Partial arch
Hard	D9944	D9946
Soft	D9945	no code

Two things fall out of that grid, and both cause real misbills.

A combination hard-and-soft guard is a hard guard. The ADA has published guidance on exactly this question: when an appliance has both hard and soft components, it is reported as a hard appliance. The reasoning is that the operative part of a guard is the occlusal surface, and the material meeting that surface is what determines the therapeutic effect. A soft liner makes a laminate guard more comfortable to wear without changing what it is. So a laminate full-arch guard is D9944 and a laminate partial-arch guard is D9946, and neither one is D9945.

There is no soft partial-arch code. The grid has an empty cell, and D9946 does not fill it. A material note on a claim does not convert a hard-appliance code into a soft one. If a soft partial appliance is genuinely what was delivered, it goes out on the unspecified adjunctive procedure code, D9999, with full documentation, and it is worth calling the carrier before you submit rather than after the denial.

Picking the code at the delivery appointment

The clinical decision is the dentist’s. The coding decision comes off the lab slip and the delivery note, in this order.

1. Is it a guard at all? Protecting teeth from grinding and clenching keeps you in the D9944 to D9946 range. Treating a diagnosed TMD is D7880. Treating sleep apnea is D9947. Sports is D9941.
2. Does the biting surface meet hard material? If yes, you are on a hard code even when the appliance also has a soft component. If the whole appliance is soft, you are on D9945 and the arch question is already settled, because soft only exists as full arch.
3. How much of the arch does it cover? Full arch is D9944. Anything short of it, including an anterior-only deprogrammer or NTI-type device, is D9946.
4. Which arch is it on? The code does not say maxillary or mandibular, but carriers ask. Arch identification is a stated claim requirement on published guard policies, and frequency limits are commonly written per arch, so the claim needs it even though the code does not carry it.
5. Is this a new appliance or work on an existing one? Repairing or relining an existing guard is D9942 and adjusting one is D9943. New for CDT 2026, D9936 reports cleaning and inspecting an existing guard, per appliance, though early carrier treatment of it is mostly non-covered or bundled into the original guard fee.

Coverage and how carriers treat partial-arch guards

Guard coverage is plan-dependent across the board, and D9946 sits at the weak end of it. The recurring patterns, all of which have to be verified against the specific contract rather than assumed:

Plans that exclude occlusal guards entirely. A significant share treat guards as cosmetic, non-essential, or as appliances for a parafunctional habit and exclude every code in the family.

Plans that cover guards but carve out partial arch specifically. This is the pattern to know for D9946, and it is written down. Utah’s PEHP 2026 CDT code guide lists partial-arch occlusal guards in its exclusions and marks D9946 not covered, while covering D9944 and D9945 at one per arch in a seven-year period. A biller reading “occlusal guards are covered” off an eligibility call will not see that carve-out.

Plans that require a documented bruxism diagnosis. Where guards are covered, medical necessity is usually gated on documentation rather than assumed. PEHP conditions its guard benefit on documented severe sleep bruxism and asks for a narrative describing clinical signs along with a summary of the radiographic findings that show the wear. The chart has to show damage, not just a complaint.

Frequency limits, and they are long. Three to five years is the interval most offices quote, but longer windows exist and PEHP’s seven-year-per-arch limit is a reminder not to guess. Repairs and adjustments are also frequently bundled into the original guard fee for a period after delivery. PEHP bundles them for the first six months and then allows one adjustment and one repair for the life of the appliance, which is the shape of the rule to look for even where the numbers differ.

The practical consequence is that a predetermination on D9946 specifically, not on “occlusal guards” generally, is the step that prevents the patient-billing complaint. Verify the code, get the answer in writing, and have the financial agreement signed before the impression.

Documentation that supports the claim

Build the claim around the two facts the code itself cannot carry, then the necessity:

• Arch identification. Maxillary or mandibular. It is a stated submission requirement on published guard policies and it is what frequency limits are counted against.
• The span. A line confirming the appliance covers only part of the arch, and which teeth. This is what separates the claim from a D9944 in an audit.
• The bruxism complaint and the clinical findings. Wear facets with tooth numbers, attrition, fractured restorations with no traumatic cause, patient-reported or partner-reported nighttime grinding. Plans that gate on medical necessity want damage described specifically, not a template sentence repeated across every guard claim.
• A summary of the radiographic findings. Some policies ask for it in the narrative and accept the description without the images attached. Say what the bitewings or the panoramic actually show.
• The delivery date. The date of service on a guard claim is the delivery appointment, not the impression. It also anchors the clock on any repair, reline, or adjustment billed later.

For the record itself, keep the material and the rationale for a partial-arch design. Anterior-only appliances carry a documented risk of unintended occlusal change when worn unsupervised, since uncovered posterior teeth can erupt over time, so the wear instructions and the follow-up schedule belong in the chart on their own merits. They are also what a records request wants to see.

What to get right in your PMS

The menus differ across Open Dental, Dentrix, Eaglesoft, Curve, and Carestream, but the setup that prevents these denials is the same:

1. Label the guard codes by material and span, not by the word guard. If D9944 and D9946 both read as “hard night guard” in a pick list, the partial-arch appliance will get billed as full arch. Put “full arch” and “partial arch” in the description text.
2. Make arch a required field on guard procedures. The code does not carry it and the carrier requires it. Systems that let a guard post without an arch will produce claims that pend for information.
3. Post on the delivery date. Not the impression date. Every downstream limitation runs from delivery.
4. Keep D9940 out of the fee schedule. The retired by-report guard code still resurfaces from old treatment-plan templates and rejects as a discontinued code. See D9940.
5. Carry D9942, D9943, and the new D9936 in the list. Repair and reline, adjustment, and cleaning and inspection each have their own code. Offices without them set up tend to fold the work into an unbilled visit or, worse, re-bill a whole new guard.
6. Write the non-covered posting rule down. Decide in advance how the office handles a D9946 that denies as excluded, and put it in the collections notes so the answer does not change with whoever is working the account.

For how the arch, tooth numbers, and remarks field are filled in on the claim itself, see the ADA dental claim form guide.