Summary & Overview
CDT D2140: Amalgam, One Surface, Primary or Permanent
CDT code D2140 denotes a single-surface amalgam restoration for primary or permanent teeth, a common restorative dental procedure used to repair decay or minor tooth damage. Nationally, this code matters because it captures a routine restorative service that influences utilization patterns, coverage policies, and adjudication practices across dental and medical payers. It is also a benchmark for comparing alternative restorative materials and clinical approaches.
Key payers in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, and UnitedHealthcare. Readers will find coverage and billing context for these major commercial payers, including typical sites of service and clinical indications that justify the procedure. The overview covers how D2140 fits within restorative coding, relationships to adjacent restorative codes, and common diagnostic reasons for use.
This publication provides practical insights into coding specificity, common clinical contexts for use, and payer coverage considerations relevant to dental practices, billing teams, and policy analysts. It highlights where more detailed policy or documentation guidance may be needed and notes when input data is missing. Data not available in the input is identified where applicable.
Billing Code Overview
CDT code D2140 represents amalgam restoration of one surface on a primary or permanent tooth. This dental procedure involves placing a silver amalgam filling to restore tooth structure lost to decay or minor fracture.
Service Type: Dentistry
Typical Site of Service: Dental Office (POS 11)
Clinical & Coding Specifications
Clinical Context
A pediatric or adult patient presents to a dental office (POS 11) with a single-surface carious lesion on a primary or permanent molar identified on clinical exam and confirmed with bitewing radiographs. The patient reports localized sensitivity to thermal stimuli and chewing but no signs of irreversible pulpal involvement or acute infection. The dentist administers local anesthesia as appropriate, isolates the tooth with cotton rolls or a rubber dam, removes carious tooth structure, prepares a conservative cavity for an amalgam restoration, places and contours a single-surface amalgam, and evaluates occlusion and finishing. Typical workflow includes charting the diagnosis (for example, caries), documenting informed consent, performing the operative procedure, recording materials used (amalgam), and scheduling follow-up as needed.
Coding Specifications
-
CDT code
D2140: Amalgam - one surface, primary or permanent. -
Common Modifiers:
-
52- Reduced Services: Used when the service provided is less than described byD2140(for example, procedure started but not completed to full scope). -
76- Repeat Procedure by Same Dentist: Used when the identical procedureD2140is repeated by the same dentist on the same date of service due to documented failure or need for replacement. -
Provider Taxonomies and Specialties:
-
1223G0001X— General Practice Dentist -
1223D0001X— Dental Public Health -
1223P0221X— Pediatric Dentist
Related Codes
-
D2150— Amalgam - two surfaces, primary or permanent- Relationship: Used when the restorative need extends to two surfaces instead of one; may be selected instead of
D2140when lesion size or extension requires a two-surface amalgam.
- Relationship: Used when the restorative need extends to two surfaces instead of one; may be selected instead of
-
D2160— Amalgam - three surfaces, primary or permanent- Relationship: Represents a larger multi-surface restoration; used as an alternative to
D2140when greater tooth structure is involved.
- Relationship: Represents a larger multi-surface restoration; used as an alternative to
-
D2330— Resin-based composite - one surface, anterior- Relationship: Anterior one-surface composite is an alternative restorative material for anterior teeth; not a direct substitute for posterior amalgam
D2140but relevant when tooth location and material preference differ.
- Relationship: Anterior one-surface composite is an alternative restorative material for anterior teeth; not a direct substitute for posterior amalgam
-
D2391— Resin-based composite - one surface, posterior- Relationship: A posterior one-surface composite is a material-based alternative to
D2140; may be used in similar clinical scenarios depending on clinical judgment and patient factors.
- Relationship: A posterior one-surface composite is a material-based alternative to
-
D2940— Protective restoration- Relationship: Temporary or protective restorations may be used prior to definitive
D2140placement or when definitive restoration is deferred; can be used earlier in the treatment sequence.
- Relationship: Temporary or protective restorations may be used prior to definitive
Related Diagnoses
-
K02.3— Arrested dental caries- Clinical relevance: Represents carious lesions that have halted progression; may still require restoration if structure is compromised or for occlusal form, making
D2140appropriate if a one-surface amalgam is placed.
- Clinical relevance: Represents carious lesions that have halted progression; may still require restoration if structure is compromised or for occlusal form, making
-
K02.9— Dental caries, unspecified- Clinical relevance: General documentation of caries where tooth-specific details warrant restoration with a one-surface amalgam
D2140.
- Clinical relevance: General documentation of caries where tooth-specific details warrant restoration with a one-surface amalgam
-
K03.81— Cracked tooth- Clinical relevance: A cracked tooth with a one-surface defect may be restored with a one-surface amalgam when clinically indicated.
-
K08.8— Other specified disorders of teeth and supporting structures- Clinical relevance: Miscellaneous tooth disorders that result in a defect or structural compromise treatable with a single-surface amalgam restoration.
-
K04.7— Periapical abscess without sinus- Clinical relevance: Represents pulpal/periapical pathology; if resolved or when restoration of a one-surface defect is part of overall care,
D2140may be used after appropriate endodontic or infection management.
- Clinical relevance: Represents pulpal/periapical pathology; if resolved or when restoration of a one-surface defect is part of overall care,
-
K05.6— Periodontal disease, unspecified- Clinical relevance: Periodontal disease may contribute to tooth structure loss or root exposure requiring restorative intervention;
D2140applies when a single-surface amalgam is indicated.
- Clinical relevance: Periodontal disease may contribute to tooth structure loss or root exposure requiring restorative intervention;
National Reimbursement Benchmarks
National mean rates for CDT code D2140 show Medicare at $0.00 compared with BUCA (average commercial) at $60.26 mean. This highlights a large gap between Medicare and average commercial benchmarks nationally for this code.
Rate dispersion measured as the difference between the 75th and 25th percentiles varies across payers: UnitedHealthcare has a wide spread (102.80 - 81.00 = 21.80), Blue Cross Blue Shield is also wide (96.33 - 67.00 = 29.33), while Aetna is relatively tight (44.00 - 37.50 = 6.50) and Cigna Health is moderate (48.00 - 39.00 = 9.00). The table and chart below present the full breakdown.
Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.