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6C Early Childhood Tooth Decay

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 proportion of children at school entry (kindergarten) who have decayed, missing/extracted or filled teeth consistent with the pattern of ECTD to the total number of teeth examined among children.



Specific Indicators

  • Percent of kindergarten children with ECTD


Corresponding Mandatory Objectives

  • To reduce the prevalence of dental diseases in children and youth.


Corresponding National Indicators

  • None


Data Sources (see Resources: Data Sources)

Numerator & Denominator: Ontario Dental Indices Survey
Original source:
Ontario Dental Indices Survey, [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.

  • The WHO Modified Index used in the DIS ensures a code for each tooth1:

  • 00 = Sound

  • 01 = Sound with sealant

  • 02 = Decayed pit and fissure

  • 03 = Decayed smooth surface

  • 04 = Decayed both pit and fissure and smooth surface

  • 05 = Filled, with no other decay in filling or crown

  • 06 = Filled and decayed (this code is counted as “d” or “D” in all reports)

  • 07 = Missing due to caries

  • 08 = Absent or a primary tooth with a permanent successor present (congenitally/unerupted/exfoliated primary tooth/trauma). See notes in the Dental Indices Software Program Manual for more specific coding.

  • 09 = Sound abutment tooth or crowned due to trauma (a crown placed for reasons other than caries)

  • 10 = To be lost/extracted due to caries (i.e., more than two-thirds of the crown has been lost or abscessed but no visible sign of decay)

  • 99 = Missing value 

Method of Calculation 


number of school entry (kindergarten) children with ECTD

* 100

total number of kindergarten children examined


Basic Categories

  • Geographic areas: public health unit.


Indicator Comments

  • ECTD is a distinctive pattern of severe tooth decays seen in infants and toddlers.2

 Three Year Old Child with a healthy mouth 



Three year old children with early childhood tooth decay
Moderately severe                                                                      Very Severe


  • ECTD has many names including nursing caries, baby bottle tooth decay, nursing bottle syndrome, and infant feeding caries.

  • The most common cause of ECTD is improper nursing bottle habits, but it can also be caused by sweetened pacifiers and is sometimes seen in children who have been exclusively breastfed. ECTD is caused when a liquid, such as breastmilk, formula or juice, baths the teeth (except for the lower incisors which are covered by the tongue), allowing plaque bacteria to metabolize fermentable carbohydrate into acid. The acid attacks the teeth and causes caries.3 A habit prone to cause ECTD is allowing an infant to fall asleep with a bottle or while breastfeeding, thus causing the milk to pool around the teeth.

  • ECTD has the following distinctive features:3
    - Many teeth are involved;
    - Lesion development is very rapid;
    - Caries occurs on surfaces usually considered to be at low risk for decay;
    - The lower primary incisors are rarely affected;
    - The teeth are affected depending on their sequence of eruption, with the maxillary primary incisors most severely affected because they are often the first to erupt and thus subjected to the longest caries attack.

  • ECTD is not directly measured in the DIS but can be estimated using the deft/DMFT Index for specific teeth. “DMFT” refers to permanent teeth: D = Decayed, M = Missing due to caries (not from trauma, orthodontic extraction, congenitally missing, etc.), F = Filled, T = Teeth. “deft” refers to primary (baby) teeth: d = decayed, e = extracted due to caries, f = filled, t = teeth. Teeth missing for caries are not recorded because of the exfoliation process and not knowing whether such teeth were carious before they fell out.

  • ECTD is considered to be present if there are caries or restorations on two or more primary maxillary incisors or canines or if there is a total decayed, missing, filled primary teeth (dmft) score of 4 or greater.

  • The CINOT program covers treatment for ECTD. Although ECTD generally accounts for a small percentage of claims, they tend to be the most expensive.2

  • Risk of ECTD is higher in families with low income and education levels.2 Aboriginal children have been found to have a high prevalence of ECTD.4

  • 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 the other dental indicators. However, information about youth is not available. Generally, information is available only for children on school entry in most health units. 

  • The draft Mandatory Health Programs and Services Guidelines of January 2003 had the following objective: “an increased proportion of children will be free from Early Childhood Tooth Decay (ECTD)”. This indicator corresponds to this objective.

  • 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.
    - 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.5
    - Poor oral health can lead to poor nutrition and decreased quality of life due to pain, and chewing and speech problems.5

  • There is a strong link between oral health and income. Low-income children and new immigrants are most likely to have poor oral health.5

Cross-References to Other Sections


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

  2. Abbey PL. A case-control study to determine the risk factors, markers and determinants for the development of nursing caries in the four-year-old population of North York. Master’s thesis, 1998.

  3. Ripa LW. Nursing caries: A comprehensive review, September 1988. Prepared for the Oral Health Subcommittee of the Healthy Mothers, Healthy Babies Coalition.

  4. Peressini S, Leake JL, Mayhall JT, Maar M, Trudeau R. Prevalence of early childhood caries among First Nations children, District of Manitoulin, Ontario. Int J Paediatr Dent 2004;14(20):101-10.

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


Date of Last Revision: November 10, 2004

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