What D5987 means

D5987 covers a commissure splint. "D" is dental, "59" places it in the maxillofacial prosthetics area, and "87" is this commissure splint. The 'commissure' is the corner of the mouth where the upper and lower lips meet. A 'commissure splint' is a device that splints (supports/holds) the mouth corner at a proper width — resisting the scar contraction that would shrink the opening. So D5987 is the device that keeps the mouth corners open to normal width.

So it's a mouth-corner stretcher/holder — stopping scars from shrinking the mouth opening.

Microstomia — an abnormally small mouth opening — is disabling: it hampers eating (small opening limits food/utensils), oral hygiene and dental care (limited access), speech and expression, and denture insertion — and it distorts appearance. A major cause is SCAR CONTRACTION at or near the mouth corners: burns — facial/perioral burns (thermal, chemical, electrical — electrical burns from mouthing cords are a classic pediatric cause) heal with scar that contracts, drawing the commissures inward and narrowing the mouth; trauma/surgery — lacerations or surgical wounds at the lip corners scar and contract similarly; and the relentless nature of scar — scar tissue CONTRACTS as it matures (over weeks to months), so without resistance the opening shrinks progressively — often worsening after the wound looks 'healed.' A commissure splint counters this: a custom device that engages the mouth corners and holds them apart at the target width, applying steady outward tension/support to resist and reverse the contraction. Designs vary (intraoral, extraoral, or combined; often adjustable to widen the opening progressively or maintain it). It's worn per protocol (often much of the day/night, especially early when contraction is strongest) over the months that scar remodels, then tapered as the scar matures and stabilizes. Timing is key: starting early (as the burn/wound heals) prevents severe microstomia far more easily than treating established contracture later. It's used in burn rehabilitation, trauma/reconstructive care, and sometimes after surgery. It's specialized maxillofacial work, often team-based (burn units, surgeons). Coverage is medical/reconstructive, by report. This code is in the maxillofacial prosthetics area. Documentation supports the claim.

When it's typically used

D5987 is reported for a commissure splint — a custom device holding the mouth corner(s) at a proper width to prevent or treat microstomia from scar contraction (burns, trauma, surgery at the lip corners). It applies steady outward support to resist/reverse contracture over the months scar remodels, preserving mouth opening for eating, hygiene, speech, and appearance. Often used in burn/reconstructive rehabilitation, ideally started early.

How much does D5987 cost?

A commissure splint's cost reflects a custom-fitted (often adjustable) device plus the fitting/monitoring its months-long use requires. Sample fee-schedule values (e.g., some state Medicaid programs) place it around the $125 level as the base allowance, varying by design/region. It's a medical/reconstructive benefit (burn/trauma rehabilitation), by report. Verify coverage with the relevant plan.

Is D5987 covered by insurance?

Coverage for a commissure splint is usually a medical/reconstructive benefit (preventing/treating microstomia after burns, trauma, or surgery), determined by report. Documentation of the injury/cause, the microstomia risk or measurement, and the splinting program supports the claim. It's often part of burn or reconstructive rehabilitation and coordinated with that team. Verifying coverage helps.

Why scars shrink the mouth

Contracting scar pulls the corners in, and understanding this clarifies the code.

Understanding scar contraction clarifies D5987. Microstomia from injury is a story of scar behaving as scar does: how scar forms — when skin/mucosa at or near the mouth corners is damaged (burn, laceration, surgery), the body heals it with scar tissue; scar contracts — maturing scar actively CONTRACTS (myofibroblasts pull the wound margins together); this is normal wound behavior, useful for closing wounds but harmful where it distorts anatomy; the commissure's vulnerability — the mouth corner is a mobile, delicate junction; contracting scar there pulls the corners inward and the opening narrows — sometimes dramatically; the deceptive timeline — contraction continues for weeks to MONTHS after the wound appears healed; a mouth that looked fine early can shrink progressively — families are often caught off guard as a child's or patient's mouth 'gets smaller' after a burn; and the electrical-burn classic — young children who bite/suck electrical cords can suffer commissure burns; as these heal, severe microstomia can develop — a well-known indication for commissure splinting.

Because scar contraction is relentless and prolonged, the counter-force must be sustained and timely — which is exactly what a commissure splint provides. So maturing scar at the mouth corners contracts and narrows the opening, often progressively. Understanding this helps patients see that microstomia from injury is a story of scar behaving as scar does — how scar forms (when skin/mucosa at or near the mouth corners is damaged/burn, laceration, surgery the body healing it with scar tissue), scar contracts (maturing scar actively CONTRACTING/myofibroblasts pulling the wound margins together, normal wound behavior useful for closing wounds but harmful where it distorts anatomy), the commissure's vulnerability (the mouth corner being a mobile delicate junction, contracting scar there pulling the corners inward and the opening narrowing, sometimes dramatically), the deceptive timeline (contraction continuing for weeks to MONTHS after the wound appears healed, a mouth that looked fine early able to shrink progressively, families often caught off guard as a child's or patient's mouth 'gets smaller' after a burn), and the electrical-burn classic (young children who bite/suck electrical cords able to suffer commissure burns, as these heal severe microstomia able to develop, a well-known indication for commissure splinting) — because scar contraction is relentless and prolonged the counter-force having to be sustained and timely (which is exactly what a commissure splint provides).

How the splint holds the opening

Steady outward support resists contracture, and understanding this clarifies the mechanism.

Understanding the mechanism clarifies D5987. A commissure splint works by opposing the scar's pull with steady mechanical support: the principle — hold the mouth corners apart at the target width so the contracting scar CAN'T draw them inward; sustained gentle tension over time both maintains the opening and can gradually stretch established contracture back toward normal; the designs — vary by case: intraoral components engaging the arches/dentition, extraoral components bearing against the mouth corners, or combined designs; many are ADJUSTABLE — allowing the width to be increased progressively (to regain opening) or maintained (to hold gains); the fit — custom-made from the patient's model to apply support at the commissures comfortably and effectively without damaging tissue; the wear schedule — typically worn a great deal of the time early on (when contraction is strongest — often day and night as tolerated), then tapered as scar matures; consistency is what defeats contraction; and progression/maintenance — the clinician adjusts the device over the months, widening or holding as the tissue responds, monitoring the commissure tissue for tolerance.

It's the same battle as other scar-contracture splinting (like burn splints elsewhere on the body): steady position against relentless contraction, sustained until the scar matures. So the splint applies sustained outward support that resists and can reverse the contracture. Understanding this helps patients see that a commissure splint works by opposing the scar's pull with steady mechanical support — the principle (holding the mouth corners apart at the target width so the contracting scar CAN'T draw them inward, sustained gentle tension over time both maintaining the opening and able to gradually stretch established contracture back toward normal), the designs (varying by case: intraoral components engaging the arches/dentition, extraoral components bearing against the mouth corners, or combined designs, many being ADJUSTABLE, allowing the width to be increased progressively/to regain opening or maintained/to hold gains), the fit (custom-made from the patient's model to apply support at the commissures comfortably and effectively without damaging tissue), the wear schedule (typically worn a great deal of the time early on/when contraction is strongest, often day and night as tolerated, then tapered as scar matures, consistency being what defeats contraction), and progression/maintenance (the clinician adjusting the device over the months, widening or holding as the tissue responds, monitoring the commissure tissue for tolerance) — it being the same battle as other scar-contracture splinting (like burn splints elsewhere on the body): steady position against relentless contraction, sustained until the scar matures.

Why early treatment matters most

Prevent contracture rather than fight it later, and understanding this clarifies the timing.

Understanding timing clarifies D5987. With commissure splinting, WHEN matters enormously: prevention beats reversal — it's far easier to HOLD a normal opening (preventing contraction from ever narrowing it) than to stretch back a mouth already shrunk by mature, established scar; starting the splint early — as the burn/wound heals and before contraction consolidates — often prevents significant microstomia altogether; the window — the strongest contraction happens over the first weeks-to-months of scar maturation; splinting through that window resists the pull when it's most aggressive; established contracture is harder — if severe microstomia has already set in with mature scar, treatment is longer and harder (progressive stretching over extended time, sometimes surgery/commissuroplasty to release scar, followed by splinting to hold the surgical result); prevention avoids that path; the burn-team habit — this is why burn and reconstructive teams incorporate commissure splinting into rehabilitation protocols early, alongside other anti-contracture measures; and adherence — because the payoff comes from sustained early wear, patient/family education and support are crucial (a child who won't wear the device, or a family who stops early thinking healing is 'done,' can lose ground fast).

The lesson mirrors trismus and vestibuloplasty care: get ahead of the tissue's tendency, don't chase it. So early, sustained splinting prevents microstomia far more easily than treating established contracture. Understanding this helps patients see that with commissure splinting WHEN matters enormously — prevention beats reversal (it being far easier to HOLD a normal opening/preventing contraction from ever narrowing it than to stretch back a mouth already shrunk by mature established scar, starting the splint early/as the burn/wound heals and before contraction consolidates often preventing significant microstomia altogether), the window (the strongest contraction happening over the first weeks-to-months of scar maturation, splinting through that window resisting the pull when it's most aggressive), established contracture is harder (if severe microstomia has already set in with mature scar treatment being longer and harder/progressive stretching over extended time, sometimes surgery/commissuroplasty to release scar followed by splinting to hold the surgical result, prevention avoiding that path), the burn-team habit (this being why burn and reconstructive teams incorporate commissure splinting into rehabilitation protocols early, alongside other anti-contracture measures), and adherence (because the payoff comes from sustained early wear patient/family education and support being crucial, a child who won't wear the device or a family who stops early thinking healing is 'done' able to lose ground fast) — the lesson mirroring trismus and vestibuloplasty care: get ahead of the tissue's tendency, don't chase it.

Where D5987 fits in the codes

D5987 is the mouth-opening splint among the maxillofacial codes, and understanding this clarifies the coding.

Understanding where D5987 sits clarifies the coding. D5987 is among the maxillofacial prosthetics codes (D5900s), among the rehabilitation/treatment-support devices — those that manage tissue behavior rather than replace structures: D5987 (commissure splint — this code: holds the mouth CORNERS open against scar contraction), D5988 (surgical splint — stabilizes/positions structures related to surgery), D5982 (surgical stent — supports grafts/healing sites), D5937 (trismus appliance — stretches a jaw with restricted opening). Note the D5937 contrast: trismus is restricted opening from JAW-muscle/fibrosis issues (opening the jaw wider); microstomia is a small mouth from LIP-CORNER scar (widening the mouth aperture) — related in spirit (fighting contracture/restriction) but different anatomy and device.

So D5987 is precisely: a commissure splint (the device holding the mouth corners at proper width against scar contraction — microstomia prevention/treatment). It's distinguished from the trismus appliance (D5937 — jaw opening vs mouth-corner width), the surgical splint (D5988 — surgical stabilization), and the restorative prostheses by its specific job. The provider codes D5987 for the commissure device. So D5987 is the microstomia/commissure splint in the maxillofacial codes. Understanding this helps patients see that D5987 is among the maxillofacial prosthetics codes (D5900s) among the rehabilitation/treatment-support devices (those that manage tissue behavior rather than replace structures) — D5987 (commissure splint, this code: holds the mouth CORNERS open against scar contraction), D5988 (surgical splint, stabilizes/positions structures related to surgery), D5982 (surgical stent, supports grafts/healing sites), D5937 (trismus appliance, stretches a jaw with restricted opening) — the D5937 contrast being notable (trismus being restricted opening from JAW-muscle/fibrosis issues/opening the jaw wider, microstomia being a small mouth from LIP-CORNER scar/widening the mouth aperture, related in spirit/fighting contracture-restriction but different anatomy and device) — so D5987 is precisely a commissure splint (the device holding the mouth corners at proper width against scar contraction, microstomia prevention/treatment), distinguished from the trismus appliance (D5937, jaw opening vs mouth-corner width), the surgical splint (D5988, surgical stabilization), and the restorative prostheses by its specific job, the provider coding D5987 for the commissure device.

Frequently asked questions

What is the D5987 dental code?

It's a commissure splint — a custom device that holds the corner(s) of the mouth open to a proper width, preventing or treating microstomia (an abnormally small mouth opening) caused by scar contraction — most often after burns, trauma, or surgery at the lip corners. It applies steady outward support to resist and reverse the shrinking as scars heal, preserving mouth function and appearance.

What causes the mouth to shrink?

Scar contraction. When the mouth corners are injured (burns — including electrical burns in children who bite cords — lacerations, or surgery), the wounds heal with scar, and maturing scar actively contracts over weeks to months. At the mobile mouth corner, that pull draws the opening inward and narrower — often progressively, even after the wound looks healed. The splint opposes that pull.

How does the splint work?

By holding the mouth corners apart at a target width so the contracting scar can't draw them in — steady, sustained support that both maintains the opening and can gradually stretch established contracture back toward normal. Designs vary (intraoral, extraoral, or combined), and many are adjustable to widen progressively or hold the gains. It's worn heavily early, then tapered as scar matures.

Why is starting early so important?

Because preventing contracture is far easier than reversing it. Starting the splint as the wound heals — before scar contraction narrows the mouth — often prevents significant microstomia entirely. Once severe microstomia sets in with mature scar, treatment is much longer and harder, sometimes requiring surgery to release the scar first. Burn teams build early splinting into rehabilitation for exactly this reason.

How is it different from a trismus appliance (D5937)?

Different problem and anatomy: a trismus appliance opens a jaw that can't open wide (from muscle/tissue fibrosis, often after radiation). A commissure splint widens a small mouth aperture caused by lip-corner scar. Both fight restriction, but one works on jaw opening and the other on the width of the mouth's opening at the corners.

Is it covered, and what does it cost?

It's usually a medical/reconstructive benefit (burn/trauma rehabilitation), by report — coordinated with the burn or reconstructive team. Sample fee schedules list a base allowance around $125, varying by design and region. Documentation of the injury and the microstomia risk or measurement supports the claim. Verify your specific coverage.

This page is an independent, plain-language explanation for general information only. It is not billing, coding, or clinical advice. For the official CDT descriptor and current-year wording, refer to the American Dental Association.