icdas-chart

Icdas Decision Tree

Diagnostic Flowchart

To determine the appropriate ICDAS code, begin by observing the tooth surface while wet.

Caries Assessment Process¹

1. Is caries visible when the tooth is wet?
   • Yes: Evaluate for cavitation or shadows.
     • Is there a cavity with exposed dentin?
       • Yes: Determine the extent of the involvement.
         • More than half of the tooth involved?
           • Yes: Code 6
           • No: Code 5
       • No: Check for underlying shadows.
         • Is there an undermining shadow?
           • Yes: Code 4
         • No: Check for micro-cavitation.
           • Is there micro-cavitation?
             • Yes: Code 3
             • No: Determine the location of the lesion.
               • Lesion confined to the base of the fissure?
                 • Yes: Code 1
                 • No: Code 2
   • No: Dry the surface and re-examine.
     • Is there any opacity or discoloration after drying?
       • Yes: Code 1
       • No: Code 0

Treatment By International Caries Detection And Assessment System Icdas Classification

Classification and Clinical Definitions

• Code 0: Sound Tooth Structure

  • Definition: No evidence of caries. Ignore developmental defects (enamel hyperplasia, fluorosis) or surface stains.
  • Histology: No enamel demineralization or narrow zone of opacity.
  • Charting: No lesion charted.

• Code 1: Early Stage Decay (Initial)

  • Definition: No color change visible when wet. After 5 seconds of air drying, carious opacity or discoloration is visible, limited to the pit and fissure.
  • Histology: Enamel demineralization limited to the outer 50% of the enamel layer.
  • Charting: Incipient lesion.

• Code 2: Early Stage Decay (Distinct)

  • Definition: Carious opacity (white spot lesion) and/or brown carious discoloration visible when wet; wider than the natural fissure/fossa.
  • Histology: Demineralization involving between 50% of the enamel and the outer 1/3 of the dentin.

• Code 3: Established Decay (Microcavitation)

  • Definition: Microcavitation due to caries with no visible dentin or underlying shadow.
  • Histology: Demineralization involving the middle 1/3 of dentin; clinically microcavitated.
  • Charting: Primary or secondary caries.

• Code 4: Established Decay (Shadow)

  • Definition: Dentin decay shows through the enamel with or without localized enamel breakdown.
  • Histology: Demineralization involving the middle 1/3 of the dentin.

• Code 5: Severe Decay (Cavitated)

  • Definition: Clinical cavitation involving less than 1/2 of the tooth surface.
  • Histology: Demineralization involving the inner 1/3 of dentin, potentially reaching the pulp.

Icdas Treatment Guidelines²

• Code 6: Severe Decay (Extensive)
  • Definition: Clinical cavitation involving more than 1/2 of the tooth surface.
  • Histology: Demineralization involving the inner 1/3 of dentin, potentially reaching the pulp.

Treatment Recommendations by Caries Risk Assessment (CRA)

• Low Risk

  • Codes 0-1: Sealant optional.
  • Code 2: Caries biopsy unless caries is arrested.
  • Code 3: Minimally invasive restoration.
  • Code 4: Restore with resin composite or amalgam.
  • Codes 5-6: Test pulp vitality; use vital pulp therapy techniques. Restore with composite or amalgam.

• Moderate/High Risk

  • Code 0: Sealant recommended (no preparation).
  • Code 1: Sealant recommended (no preparation).
  • Code 2: Caries biopsy (Bur 1/4).
  • Code 3: Preparation with Bur 1/4 or 1.
  • Code 4: Preparation with Bur 330.

CDT Coding Guidelines

• D1351: Sealant (Codes 0, 1).
• D1352: Preventive Resin Restoration (PRR) for Code 2 if decay stops in enamel.
• D2330: Resin Composite (Code 2 if in dentin; Codes 3, 4).
• D2140: Amalgam (Code 4).
• D3110 / D3120: Direct (DPC) or Indirect (IPC) Pulp Capping (Codes 5, 6). Restoration code depends on the number of surfaces involved.

Footnotes

1. Original PDF page 1: icdas-chart, p.1 ↩

2. Original PDF page 2: icdas-chart, p.2 ↩