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The Dental Odontogram uses the FDI (Fédération Dentaire Internationale) World Dental Federation notation system for tooth identification and surface mapping. This ensures anatomically-correct treatment placement.

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FDI notation system

The FDI system uses two-digit numbers to identify teeth:
  • First digit: Quadrant (1-4 for permanent, 5-8 for deciduous)
  • Second digit: Position within quadrant (1-8)

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Quadrant numbering

Permanent teeth:
  18 17 16 15 14 13 12 11 | 21 22 23 24 25 26 27 28
  ------------------------------------------------
  48 47 46 45 44 43 42 41 | 31 32 33 34 35 36 37 38

Quadrant 1: Upper right (11-18)
Quadrant 2: Upper left (21-28)
Quadrant 3: Lower left (31-38)
Quadrant 4: Lower right (41-48)

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Surface-aware treatment mapping

The application maps canvas click positions to anatomical tooth surfaces based on the tooth’s FDI number and quadrant location.

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Canvas positions

Each tooth on the canvas has 5 clickable regions:
  • Top: Upper surface
  • Bottom: Lower surface
  • Left: Left side
  • Right: Right side
  • Middle: Center

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Anatomical surfaces

Dental surfaces use standardized terminology:
  • Vestibular: Facing the lips/cheeks (facial)
  • Palatina: Facing the palate (upper)
  • Lingual: Facing the tongue (lower)
  • Mesial: Toward the midline
  • Distal: Away from the midline
  • Oclusal: Biting surface (molars/premolars)
  • Incisal: Cutting edge (incisors/canines)

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Surface mapping logic

The getCorrectSurfaceMapping() function maps canvas positions to anatomical surfaces based on FDI quadrant: 
// From dental-app.js
function getCorrectSurfaceMapping(fdi) {
  const toothInfo = getToothInfo(fdi)
  if (!toothInfo) {
    return {
      top: 'vestibular',
      bottom: 'palatina',
      left: 'mesial',
      right: 'distal',
      middle: 'oclusal',
    }
  }

  const quadrant = Math.floor(fdi / 10)
  const tipo = toothInfo.tipo

  // Upper arch (quadrants 1, 2, 5, 6)
  const isUpper = [1, 2, 5, 6].includes(quadrant)
  // Right side (quadrants 1, 4, 5, 8)
  const isRight = [1, 4, 5, 8].includes(quadrant)

  // Determine biting surface name based on tooth type
  const biting =
    tipo === 'Incisivo' || tipo === 'Canino' ? 'incisal' : 'oclusal'

  return {
    top: 'vestibular',
    bottom: isUpper ? 'palatina' : 'lingual',
    left: isRight ? 'mesial' : 'distal',
    right: isRight ? 'distal' : 'mesial',
    middle: biting,
  }
}

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Quadrant-specific mapping

Tooth 11-18
  • Top → Vestibular
  • Bottom → Palatina
  • Left → Mesial (toward midline)
  • Right → Distal (away from midline)
  • Middle → Oclusal/Incisal

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Tooth data structure

Tooth information is loaded from dientes_fdi_completo.json: 
{
  "fdi": 11,
  "tipo": "Incisivo",
  "nombre": "Incisivo Central Superior Derecho",
  "arco": "Superior",
  "lado": "Derecho",
  "cuadrante": 1,
  "caras": ["vestibular", "palatina", "mesial", "distal", "incisal"]
}

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Loading tooth data

// From dental-app.js
async function loadDentalData() {
  try {
    const response = await fetch('./dientes_fdi_completo.json')
    dentalData = await response.json()
    console.log('Dental data loaded successfully')
  } catch (error) {
    console.error('Error loading dental data:', error)
  }
}

function getToothInfo(fdi) {
  if (!dentalData || !dentalData.dientes) return null
  const fdiNumber = parseInt(fdi)
  return dentalData.dientes.find((tooth) => tooth.fdi === fdiNumber)
}

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Surface-specific treatments

Certain treatments can be applied to specific surfaces:
  • Caries: Can affect individual surfaces
  • Obturación (filling): Applied to specific surfaces
  • Incrustación: Surface-specific
  • Surco Profundo: Usually oclusal/incisal
  • Restauración: Surface-specific

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Grouping treatments by surface

// From dental-app.js (exportOdontogramData)
function groupTreatmentsBySurface(treatmentList) {
  const grouped = {}
  
  treatmentList.forEach((treatment) => {
    const treatmentName = getTreatmentName(treatment.name)
    const withSides = ['CARIES', 'CARIES_UNTREATABLE', 'REF', 'NVT', 'SIL', 'RES', 'AMF', 'COF', 'INC']
    
    if (!grouped[treatment.name]) {
      grouped[treatment.name] = {
        nombre: treatmentName,
        superficies: [],
        usa_superficies: withSides.includes(treatment.name)
      }
    }
    
    // Collect surface information
    if (withSides.includes(treatment.name) && treatment.pos && toothInfo) {
      const correctMapping = getCorrectSurfaceMapping(toothNum)
      const anatomical = correctMapping[fullCanvasPosition]
      
      if (anatomical && !grouped[treatment.name].superficies.includes(anatomical)) {
        grouped[treatment.name].superficies.push(anatomical)
      }
    }
  })
  
  return grouped
}
This produces output like: 
{
  "nombre": "Obturación",
  "superficies": ["vestibular", "mesial"],
  "usa_superficies": true
}

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Mesial/distal orientation

The key feature of FDI mapping is automatic mesial/distal correction. The system knows that mesial always points toward the midline, regardless of whether the tooth is on the left or right side.

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Example: Tooth 11 vs Tooth 21

Clicking the left side of the canvas:
  • Canvas position: left
  • Quadrant 1 mapping: left → mesial
  • Result: Mesial surface (correct - toward midline)
Without FDI-aware mapping, both would incorrectly show the same surface name.

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Clinical accuracy

The FDI mapping system ensures:

Anatomical correctness

Treatments are documented on the correct anatomical surface

Professional standards

Uses internationally-recognized FDI notation

Accurate records

Export data matches clinical documentation standards

Clear communication

Surface names are unambiguous for dental professionals

Geometry system

Technical details of position mapping

JSON export

How surface data appears in exports

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