D2140Amalgam, One Surface, Primary or Permanent

What This Code Covers

D2140 covers the placement of a single-surface amalgam (silver) filling on a primary or permanent tooth. The filling restores one surface of the tooth that has been damaged by decay. This code includes all steps of the procedure: cavity preparation, placement of any needed liners or bases, condensation of amalgam, and carving and polishing of the restoration.

Billing Guide

Bill this code when:

• Decay is limited to one surface of the tooth and amalgam is the material placed
• The tooth is either a primary (baby) tooth or a permanent tooth
• The filling replaces only one surface (occlusal, mesial, distal, buccal, or lingual)
• Amalgam is chosen over composite as the restorative material

Do not bill this code when:

• The filling spans two or more surfaces of the tooth. Use D2150 for two surfaces or D2160 for three surfaces
• Composite (tooth-colored) material is used instead of amalgam. Use D2391 for posterior or D2330 for anterior
• The restoration is a preventive resin filling with no caries into dentin. Consider D1352 instead
• The filling is placed on a temporary basis only. Use D2940 for a sedative or temporary filling

Insurance and Denial Prevention

Key Payer Rules:

• Amalgam fillings are classified as basic restorative and typically covered at 70-80% after deductible
• Most plans have no waiting period for basic restorative, though some newer plans impose 6 months
• Frequency limits are rare for fillings but some plans restrict the number of restorations per tooth within a time period
• Amalgam is generally the least expensive filling option, so alternative benefit downgrades do not apply

Common Denials and How to Respond:

• Missing tooth number or surface -> Resubmit with correct tooth number and surface designation clearly marked on the claim form
• Duplicate claim for the same tooth and surface -> Submit documentation showing the original filling failed or a new area of decay developed, along with updated radiographs
• Service performed within a plan exclusion period -> Verify the patient's effective date and waiting period. Appeal with documentation if the plan terms were met
• Radiograph does not support the need for a filling -> Submit a narrative explaining clinical findings such as explorer stick, visual discoloration, or other diagnostic indicators not visible on film