DMFT Index Calculator

Actual permanent DMFT inventory, one independently classified status per actual FDI tooth:0sound,1decayed,2missing due to caries,3filled without current decay. Qualification, cause attribution and actual examined dentition external; unknowns not imputed; not double count teeth or infer disease risk.

Description

DMFT counts decayed, missing due to caries and filled permanent teeth.

DMFT counts decayed, missing due to caries and filled permanent teeth.^{[1, 2]}

One independently assigned status per tooth prevents double counting and preserves unknown assessments. Use this tool to count independently coded tooth statuses and retain unknown tooth IDs.

When to use DMFT Index Calculator

Use this tool to count independently coded tooth statuses and retain unknown tooth IDs. Establish the qualified examination or measurement context, matching instrument/protocol edition, site order and units.

How to use DMFT Index Calculator and understand its results

Establish the qualified examination or measurement context, matching instrument/protocol edition, site order and units.
Enter independentlyIdentifiedFdiTeeth, independentlyCodedMutuallyExclusiveToothStatus, toothEvidenceKnownFlags, using the field meanings and rules below, then run the tool.
Read result.decayedCount, result.missingOrExtractionCount, result.filledCount, result.knownIndexTotal, result.unknownToothIds. Interpret each field using the units, signs and evidence rules below.
If input validation fails, correct the reported field and run again. Before applying a successful result, check the stated reference scope, units, assumptions and any retained unknown evidence.

Input field	Meaning	Value type	Requirement
independentlyIdentifiedFdiTeeth	Independently identified fdi teeth	list of string	Required
independentlyCodedMutuallyExclusiveToothStatus	Independently coded mutually exclusive tooth status	list of number	Required
toothEvidenceKnownFlags	Tooth evidence known flags; 1 means known and 0 means unknown; keep the same item order	list of number	Required

Supply nonempty unique exact FDI tooth strings from the permanent quadrants 1–4, with positions 1–8 and at most 32 teeth. Supply aligned integer status codes 0–3 and binary known flags. Validate every code, including unknown placeholders. Count known codes 1, 2 and 3 separately and add them for the known index total; retain unknown tooth IDs in caller order. Clinical cause attribution and mutually exclusive status assignment are independent inputs. An all-unknown record is allowed and returns zero known counts with its unknown IDs.

Status code	Meaning
0	0: sound
1	1: decayed
2	2: missing due to caries
3	3: filled without current decay

decayed=count(known and code=1); missingOrExtraction=count(known and code=2); filled=count(known and code=3); knownIndexTotal=decayed+missingOrExtraction+filled

Apply the field units and exact ordering, boundary and evidence rules above.

Output field	Meaning	Value type
result	Structured result containing the calculation or selected reference fields below	object
result.decayedCount	Known status-1 tooth count	number
result.missingOrExtractionCount	Known status-2 tooth count under the supplied dentition-specific convention	number
result.filledCount	Known status-3 tooth count	number
result.knownIndexTotal	Sum of known decayed, missing/extraction and filled tooth counts	number
result.unknownToothIds	Examined tooth IDs whose evidence is unknown	list of values

json

{
  "input": {
    "independentlyIdentifiedFdiTeeth": [
      "11",
      "12",
      "13"
    ],
    "independentlyCodedMutuallyExclusiveToothStatus": [
      1,
      2,
      3
    ],
    "toothEvidenceKnownFlags": [
      1,
      1,
      1
    ]
  },
  "output": {
    "result": {
      "decayedCount": 1,
      "missingOrExtractionCount": 1,
      "filledCount": 1,
      "knownIndexTotal": 3,
      "unknownToothIds": []
    }
  }
}

Limitations and assumptions

Interpretation depends on the independently assigned codes and instrument or dentition scope. Unknown evidence is retained rather than treated as a known zero. The calculation does not diagnose disease, assign clinical grades or determine treatment.

Every listed input requires an explicit value. Unexpected fields, incorrect value types, nonfinite numbers and sparse numeric arrays fail validation; tool-specific bounds and alignment rules apply as described above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful calculation that reports a false comparison or retains unknown evidence.

Alternative or Complementary methods

Use Enamel Hypoplasia Count Tool to examine a related aspect: Enamel hypoplasia counts require individually examined teeth and qualified findings.

Use DEF Index Calculator where its separate inputs and scope apply: The primary-tooth def inventory distinguishes decay, indicated extraction and filling.

References

DMFT Index Calculator — tool.io
Oral Health Surveys: Basic Methods, fifth edition — World Health Organization

Similar or alternative tools

Enamel Hypoplasia Count Tool
Enamel hypoplasia counts require individually examined teeth and qualified findings.
DEF Index Calculator
The primary-tooth def inventory distinguishes decay, indicated extraction and filling.