# Caries prevalence

## - Caries Prevalence: DMFT and DMFS -

**DMFT and DMFS **describe the amount - the prevalence - of dental caries in an individual. DMFT and DMFS are means to numerically express the caries prevalence and are obtained by calculating the number of

- Decayed (D)
- Missing (M)
- Filled (F)

teeth (T) or surfaces (S).

It is thus used to get an estimation illustrating how much the dentition until the day of examination has become affected by dental caries. It is either calculated for 28 (permanent) teeth, excluding 18, 28, 38 and 48 (the "wisdom" teeth) or for 32 teeth (The Third edition of "Oral Health Surveys - Basic methods", Geneva 1987, recommends 32 teeth). Thus:

- How many teeth have caries lesions (incipient caries not included)?
- How many teeth have been extracted?
- How many teeth have fillings or crowns?

The sum of the three figures forms the DMFT-value. For example: DMFT of 4-3-9=16 means that 4 teeth are decayed, 3 teeth are missing and 9 teeth have fillings. It also means that 12 teeth are intact.

Note: If a tooth has both a caries lesion and a filling it is calculated as D only. A DMFT of 28 (or 32, if "wisdom" teeth included) is maximum, meaning that all teeth are affected.

A more detailed index is DMF calculated **per tooth surface, DMFS**. Molars and premolars are considered having 5 surfaces, front teeth 4 surfaces. Again, a surface with both caries and filling is scored as D. Maximum value for DMFS comes to 128 for 28 teeth.

For the **primary dention**, consisting of maximum 20 teeth, the corresponding designations are "deft" or "defs", where "e" indicates "extracted tooth".

In Tables presenting caries data for **adults**, the following designations are used:

DMFT: Mean number of decayed, missing or filled teeth |

**%DMFT:** |
Percentage of population affected with dental caries |
**MT: ** |
Mean number of missing teeth |

**%D: ** |
Percentage with untreated decayed teeth |
**MNT: ** |
Mean number of teeth |

**DT:** |
Mean number of decayed teeth |
**%Ed: ** |
Percentage edentulous |

Online Calculation of DMFT/dmft and SIC Index