Early and Severe Early Childhood Caries among 2- to 5-year-olds in the 2009 New Zealand National Oral Health Survey: Prevalence and Associated Factors

Background: Few national oral health surveys have included children under five years old; the first for New Zealand was the 2009 oral health survey. This survey included a clinical examination of 256 children aged two to five years old and an interview with each child’s primary caregiver which included information about both the child and the caregiver.

Methods: Using a confidentialised unit record file, supplied by Statistics New Zealand, the prevalence of early childhood caries (ECC: d3mft>0) and severe early childhood caries (S-ECC: using the age-specific criteria described in Drury et al 1999) were calculated and merged into the dataset containing responses to the interview questions. Analysis was carried out using svy commands (to account for the complex sample design) in Stata/IC version 13.

Results: For all 256 two- to five-year-olds the prevalence of ECC and S-ECC was 22.7% (SE 4.0) and 15.0% (SE 2.9) respectively; for three-year-olds alone: 18.3% (SE 6.5) had ECC and 7.7% (SE 3.6) S-ECC. Both ECC and S-ECC were more common among: Maori, Pacific and Asian children (than Europeans); children with high debris index scores; children whose caregiver had no secondary school qualifications or rated their own oral health as fair or poor; and children who lived in a house with a smoker. S-ECC alone was more common among children who: had non-fluoridated water; a caregiver who had had an extraction in the last 12 months or was unpartnered and living alone; or lived in an overcrowded house.

Conclusions: The 2009 oral health survey has provided baseline data to allow future comparisons and evaluation of interventions to control ECC. Given the high costs to children, their families and health services of dealing with the consequences of ECC and S-ECC in young children more frequent data collection and diagnostic standardisation are needed.