Claims · Updated 2026-09-08 · 5 min read

What amalgam code is a posterior composite downgraded to?

The four posterior composite codes, the amalgam codes they are paid as, which teeth are in scope, and the carriers that exclude premolars or a single surface.

A downgraded posterior composite is paid at the amalgam code with the same surface count: D2391 (one surface) as D2140, D2392 (two) as D2150, D2393 (three) as D2160, D2394 (four or more) as D2161. All four pairs are in scope on posterior teeth, permanent and primary — posterior composite codes are valid on baby teeth. Anterior composites (D2330–D2335) have no downgrade target at all, because composite is the standard restoration on visible teeth. What varies between carriers is not the pair but the tooth scope: molars only, all posterior teeth, posterior except a named surface, or nothing at all.

The pairs

These pairs are the default applied when a plan says an alternate benefit applies without naming a target; individual carriers publish their own lists, and United Concordia's and Aetna's differ.

What we measured

A line is one procedure on one claim; these are paid explanation-of-benefits lines on D2391–D2394, pooled across the practices Kaylie serves, measured on 8 September 2026. The Ameritas, Humana, Aetna, Principal and Anthem rows are built on fewer than 200 lines each — directional, not precise. Humana stated none of its 13 downgrades, on a carrier we see comparatively little of.

What the carriers' own policies say — and who is excluded

Molars only. UnitedHealthcare's federal brochure flags all four codes with "Alternate benefitting for molars only" (UnitedHealthcare Dental FEDVIP Official Plan Brochure 2025). MetLife's provider manual scopes its clause to "a composite restoration… submitted on a molar tooth" (MetLife Preferred Dentist Program (PDP) Resource Manual, undated), and Ameritas's product document to "a composite on a molar tooth" (Ameritas Life Insurance Corp — AM 668 (8-25) Product Document, 2025). Physicians Mutual says the same thing from the other side: "D2140 — D2394… Porcelain and resin benefits are considered for anterior and bicuspid teeth only" (Physicians Mutual Dental — Over 400 Covered Procedures, undated).

Bicuspids and molars. United Concordia gives the tooth numbers, the only carrier document that does: "when Resin-based composite, posterior (D2391-D2394) is reported, payment will be made for a comparable Amalgam restoration (D2140-D2161) on bicuspids and molars (teeth 1-5, 12-21, 28-32)" (United Concordia Dental PPO Clinical Policy, 2026).

All posterior teeth. Aetna: "An alternate benefit of an amalgam will be provided on posterior teeth" on D2391 and repeated across D2392–D2394 (Aetna Dental FEDVIP 2026 Brochure, OPM). Humana uses the same words on the same four codes (2026 Humana Dental FEDVIP Brochure, OPM 02AP-10).

Excluded surfaces and excluded teeth. Delta Dental of Illinois exempts one surface of one tooth type: "When a resin filling is placed on a molar or pre-molar (except on the facial surface of a pre-molar), the level of benefits will be limited to that of an amalgam filling" (Delta Dental of Illinois Individual Platinum Dental Plan Booklet, undated). Delta Dental of New Jersey exempts the first premolars: "Benefits will be paid for composite restorations only when placed in front teeth and first premolars. Benefits for posterior teeth other than first premolars will be based on amalgam restorations" (Delta Dental of New Jersey Individual Enhanced Family PPO Plan III (ACA), undated). Delta Dental of Massachusetts downgrades only multi-surface work: "synthetic (white) fillings are limited to single surface restorations for posterior teeth. Multi-surface synthetic restorations on posterior teeth… will be treated as an alternate benefit and an amalgam allowance will be allowed" (Delta Dental Individual and Family EPO Subscriber Certificate, undated).

Primary teeth are in scope. MassHealth writes it into state regulation: "The MassHealth agency does not pay more for a composite restoration on a posterior (primary or permanent) tooth than it would for an amalgam restoration." (MassHealth 130 CMR 420.000, Dental Services Regulation, transmittal DEN-111, undated.)

Why it depends on the plan group

Every sentence above describes a provision a plan may carry, not one it must. Blue Cross Blue Shield of Texas puts the distinction in one exchange: "Are composite resin fillings covered on all teeth? Yes. Composite resin fillings are a covered benefit on all teeth; however, alternate benefit provisions may apply." (DNoA (BCBSTX) — Commonly Asked Questions: Clinical Coverage & Billing Policy, December 2024.) "Covered" and "not downgraded" are different answers to different questions. Measured across 3,790 employer groups in August 2026, whether a plan downgrades posterior composites is settled within the group 97.7% of the time against 77.0% at carrier level; the tooth-scope answer, across 2,748 groups, 97.4% against 77.6%.

What to do

• Bill the code you performed. The substitution is the payer's to make; billing D2150 for a composite you placed is a misrepresentation.
• Compare the allowed amount to your contracted fee for the code you billed to catch the downgrades that arrive with no remark.
• Record the tooth scope with the group number — "molars only", "all posterior", "multi-surface only" — because it changes the estimate on a premolar.
• Quote the patient the difference between the composite allowance and the amalgam allowance, before treatment.
• Check your practice management system's default substitutions for D2391–D2394, which ship switched on in some systems and apply to every plan.

Numbers last refreshed September 2026.

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