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6C Fluorosis Index

Description | Specific Indicators | Corresponding Mandatory Objectives | Corresponding National Indicators | Data Sources |  Alternative Data Sources | ICD Codes | Analysis Check List | Method of Calculation |  Basic Categories | Indicator Comments | Cross-References to Other Sections | References  


  • The percentage of the children at school entry who have dental fluorosis



Dental, teeth, child, decay, cavities, caries, DIS, oral health, fluorosis, fluoride, Mandatory


Specific Indicators

  • Percentage with fluorosis


Corresponding Mandatory Objectives

  • None


Corresponding National Indicators

  • None


Data Sources (see Resources: Data Sources)

Numerator & Denominator: Ontario Dental Indices Survey (Dental Health Data)
Original source:
Public Health Unit
Distributed by: Public Health Unit
Suggested citation (see
Data Citation Notes):
Dental Indices Survey [years], [Public Health Unit], Extracted: [date]


Survey Questions

  • None


Analysis Check List

  • Determine what sampling methodology was used within a health unit before making comparisons of the DIS over time or with other health units.

  • Fluorosis is defined as having a score of 1 or more on the Fluorosis Index, 1= Parchment white colour on less than 1/3 of enamel surface, 2= Parchment white colour on 1/3 but less than 2/3 of enamel surface, 3= Parchment white colour on 2/3 or more of the enamel surface, 4=Staining and/or pitting in conjunction with 1, 2 or 3. A score of 0 indicates no fluorosis.1

Method of Calculation 


total number of children at school entry who have fluorosis

* 100

total number of kindergarten children surveyed


Basic Categories

  • Geographic areas: public health unit.


Indicator Comments

  • Dental fluorosis is the mottling and/or loss of enamel on teeth due to overexposure to fluoride during tooth development.2

  • Boards of health monitor fluoride levels for their local Municipal or Regional water supply(s) on a monthly basis according to the MOHLTC’s protocol on Monitoring the Fluoridation of Local, Municipal or Regional Water Supply. If the reported monthly average level of fluoride is below 0.8 ppm (mg/L) or above the Maximum Allowable Concentration (MAC), the board of health shall contact the Ministry of Environment for an explanation; and institute a contingency water monitoring plan.3

  • Fluorosis appears bilaterally in pairs of teeth that develop at the same time. Both teeth of a pair must be affected in the same manner to be fluorosis. Those conducting the DIS are asked to score the worst bilateral pair of homologous teeth that can be seen.1

  • Although public health units are required by Mandatory Health Programs and Services Guidelines to conduct the DIS for all school entrants, many do not have sufficient resources and instead sample only some of the children. Each public health unit uses a different methodology depending upon local resources. As a result, the DIS is not comparable across health units. Comparisons within a health unit over time may be appropriate as long as the sampling methodology has remained consistent.

  • Because the DIS is conducted for children at school entry (Junior Kindergarten and Senior Kindergarten) throughout the school year from September to June, children can range in age from 3 to 6 years.

  • The Mandatory Health Programs and Services Guidelines have the objective “to reduce the prevalence of dental diseases in children and youth”. This indicator is one measure of this objective, along with other dental indicators. However, information about youth is not available. Generally, information is available only for children on school entry in most health units.

  • Oral disorders can have a significant impact on general health and well-being:
    - Dental decay is caused by bacterial infection. It is one of the most common disorders of childhood. It can cause pain, poor sleep and poor eating habits in children. Dental decay can be a contributing factor in “failure to thrive” whereby children have low weight and height for their age.4
    - Periodontal disease, a chronic infection caused by bacteria that accumulate in plaque, has been linked to various diverse health problems including pre-term low birth weight babies, heart disease, stroke, pneumonia, and chronic respiratory disease.4
    - Poor oral health can lead to poor nutrition and decreased quality of life due to pain, and chewing and speech problems.4

  • There is a strong link between oral health and income. Low-income children and new immigrants are most likely to have poor oral health.4

  • The percent of children aged 5 with fluorosis for Ontario in 1993 was 10.2%.5

Cross-References to Other Sections


  1. Ontario Ministry of Health. Dental Indices Software Program Manual. December 9, 1997.

  2. Bennett S. Results from the 1993-94 Ontario Dental Health Indices Survey. PHERO 1996:355-358.

  3. Ministry of Health, Monitoring the Fluoridation of Local, Municipal or Regional Water Supply Protocol, Child Health Program. January 1, 1998.

  4. Locker D, Matear D. Oral disorders systemic health, well-being and the quality of life: A summary of recent research evidence. 

  5. Dr. Sandra Bennett, Public Health Division, Ontario Ministry of Health and Long-Term Care.

Date of Last Revision: November 10, 2004

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