ICDAS & Epidemiology Notes (Comprehensive)

Relevance of Oral Epidemiology to Clinical Practice

• Goals & objective of epidemiology in dentistry: understand distribution and determinants of dental diseases.
• Why it matters to clinicians: guides prevention, diagnosis, and treatment strategies.
• Bridges population data/health information with individual patient care.

Community vs Private Practice Approaches

• Community approach: emphasis on prevention, policy development, and surveillance.
• Private practice approach: patient-centered care focusing on diagnosis and individual treatment.
• Both rely on epidemiologic data to inform decisions.

Types of Indices in Caries Epidemiology

• Prevalence: the percentage of a population affected at a point in time (snapshot).
• Incidence: new cases over a period of time.
• Utility: track trends and plan interventions.
• Example given: DMFT (often presented as a measure of caries experience, i.e., prevalence) and incidence-rate studies.
• Important note: DMFT can be used in both prevalence and incidence contexts depending on study design.

Ideal Index Characteristics

• Valid and reliable.
• Simple and acceptable to participants and clinicians.
• Sensitive and specific for the condition.
• Importance: standardizes caries data collection across populations and over time.

DMFT/dmft and DMFS/dmfs Indices

• DMFT/DMFS: measures caries experience in permanent teeth/surfaces.
• dmft/dmfs: measures caries experience in primary teeth/surfaces.
• Letters:
  • D = Decayed
  • M = Missing (due to caries)
  • F = Filled (restored)
  • For surfaces, superscripts S are used in DMFS/dmfs.

Caries Score Calculation Example

• Example: D = 2, M = 1, F = 3.
• DMFT = D + M + F = 2 + 1 + 3 = 6.
• Process: add all decayed, missing, and filled components to obtain the overall caries experience score.
• Utility: useful in surveys and patient care planning.

Caries Indices: DMFT, D1–D3, and Root Caries Index (RCI)

• DMFT/DMFS = Caries experience index (overall burden).
• D1–D3: Stages of caries progression from enamel (D1) to dentin (D3).
• RCI = (Root caries / exposed root surfaces) × 100.
  • Purpose: quantify root caries burden relative to exposed root surfaces.
  • Formula: $RCI = \frac{\text{root caries}}{\text{exposed root surfaces}} \times 100.$

Primary Aim of Caries Diagnosis

• Detect early lesions.
• Assess activity and risk.
• Guide prevention and treatment decisions.

What is ICDAS? (International Caries Detection and Assessment System)

• A standardized system to detect and assess caries.
• Ranks severity from 0 to 6.
• Used in both clinical practice and research settings.

ICDAS Coding System (0–6)

• Code 0: Sound tooth surface.
• Code 1–2: Early visual changes in enamel.
• Code 3–4: Localized enamel breakdown.
• Code 5–6: Cavitation into dentin.

Why Consider ICDAS in Treatment Planning

• Provides a logical technique for evaluating occlusal lesions and categorizing them.
• Establishes a common language to discuss lesions.
• Widely implemented globally.
• Categorizes fissure systems from best (Code 0) to worst (Code 6) with guidelines for treatment and prognosis.
• Increases clinician confidence in managing challenging lesions.

ICDAS Occlusal Caries Classification (Overview)

• ICDAS uses codes 0–6 to classify occlusal surfaces.
• For practical decision-making, codes are grouped into sound structure and three disease categories (as per ADA Caries Classification System, CCS).
• More information: www.icdas.org/education

ICDAS Classification: Code 0 (Zero)

• Histology: No enamel demineralization or only a narrow opacity band.
• Clinically: Sound tooth surface.
• Wet vs. Dry: No difference in appearance.
• Radiographically: No radiolucency.
• CCS: None
• ICDAS: 0
• Note: White opacity near grooves can be mistaken for normal hypoplasia; if no true demineralization is present, code remains 0.

ICDAS Classification: Code 1

• Histology: Demineralization limited to the outer 50% of the enamel.
• Clinically: First visual changes; opacity or discoloration.
• Radiographically: No radiolucency visible.
• Wet vs. Dry: Generally invisible when wet; visible after air-drying.
• CCS: Initial
• ICDAS: 1

ICDAS Classification: Code 2

• Histology: Demineralization involves inner 50% of enamel and outer 1/3 of dentin.
• Clinically: Distinct visual changes; opacity or discoloration wider than the pit/fissure.
• Radiographically: Possibly visible in dentin.
• Wet vs. Dry: More noticeable when wet or after drying.
• CCS: Moderate
• ICDAS: 2

ICDAS Classification: Code 3

• Histology: Demineralization involving the middle 1/3 of dentin; clinically microcavitated; dentin not visible in walls/base.
• Clinically: Localized enamel breakdown.
• Radiographically: Outer 1/3 of dentin may be involved.
• Wet vs. Dry: Visible as breakdown; microcavitation present.
• CCS: Advanced
• ICDAS: 3

ICDAS Classification: Code 4

• Histology: Demineralization involving the middle 1/3 of dentin with microcavitation.
• Clinically: Underlying shadow from dentin with or without enamel breakdown; dentin may be visible through enamel.
• Radiographically: Radiolucency extending to the middle 1/3 of dentin.
• Wet vs. Dry: Shadow more evident when wet.
• CCS: Advanced
• ICDAS: 4

ICDAS Classification: Code 5

• Histology: Demineralization involving inner 1/3 of dentin, potentially into the pulp.
• Clinically: Cavitation present; cavitation involves < 1/2 of tooth surface.
• Radiographically: Radiolucency extending to the middle 1/3 of dentin.
• Wet vs. Dry: Distinct dentin visibility; dentin visible through opaque/discolored enamel.
• CCS: Middle 1/3 of dentin (advanced disease)
• ICDAS: 5

ICDAS Classification: Code 6

• Histology: Demineralization involving inner 1/3 of dentin, potentially into the pulp.
• Clinically: Cavitation present; cavitation involves > 1/2 of tooth surface.
• Radiographically: Radiolucency in the inner 1/3 of dentin.
• Wet vs. Dry: Dentin clearly visible in walls/base.
• CCS: Inner 1/3 of dentin (extensive disease)
• ICDAS: 6

ICDAS Classification: Correlation with CCS and Practical Mapping

• Code 0: CCS None; ICDAS 0
• Code 1: CCS Initial; ICDAS 1
• Code 2: CCS Moderate; ICDAS 2
• Code 3: CCS Advanced; ICDAS 3
• Code 4: CCS Advanced; ICDAS 4
• Code 5: CCS Moderate/Advanced (depending on system); ICDAS 5
• Code 6: CCS Inner/Extensive (pulp-proximity considerations); ICDAS 6
• Note: The CCS naming helps translate ICDAS codes into treatment planning guidance.

Applying ICDAS in Clinical Scenarios

• Document and use in treatment planning.
• Assign the appropriate code (0–6).
• Assess lesion severity visually.

Modifying the Cariogenic Environment

• REDUCE SUGAR INTAKE.
• USE FLUORIDE REGULARLY.
• PROMOTE SALIVA FLOW.
• MAINTAIN ORAL HYGIENE.

Quick Knowledge Check & Practice Questions (Highlights)

• ICDAS Coding Quiz (example): A tooth shows localized enamel breakdown without visible dentin. What ICDAS code?
  • Answer: Code 3 (based on described criteria for localized enamel breakdown).
• DMFT Calculation Practice:
  • Example 1: D=2, M=1, F=3 → DMFT = $D + M + F = 2 + 1 + 3 = 6.$ (From the example on slide 7)
  • Example 2 (quiz): D=2, M=1, F=2 → DMFT = 5.
• Cariogenic Environment Question:
  • Which reduces cariogenic bacteria?
  • Correct choice: Daily fluoride use (B).

Quick Knowledge Check Answers (Summary from slides)

• ICDAS 4 indicates an underlying dentin shadow with or without enamel breakdown; radiographs may show extension to the middle 1/3 of dentin.
• DMFT for D=3, M=2, F=1 equals: $DMFT = 3 + 2 + 1 = 6.$
• Four steps to alter the cariogenic environment: 1) Reduce sugar intake, 2) Fluoride regularly, 3) Promote saliva flow, 4) Encourage home care.

References & Resources

• ICDAS Foundation: www.icdas.org
• WHO Oral Health Report: Global strategy and action plan on oral health 2023-2030; published 26 May 2024.
• Oral Epidemiology: A Textbook on Oral Health Conditions, Research Topics and Methods; Peres, Marco; 1st edition; Springer

Questions & Comments

• For further details or clarifications, refer to the ICDAS educational resources and the WHO report cited above.