Pre and Post-Water Fluoridation Survey Report released

Northland District Health Board's Pre and Post Fluoridation Monitoring Survey report was tabled today at the Far North District Council by The University of Otago's Professor of Dental Epidemiology and Public Health, Murray Thomson.  The results provide the Council with baseline and follow up epidemiology data at the two year point of the monitoring survey.

The survey, conducted by principal investigator Dr Sunitha Gowda, is a cross-sectional quantitative research survey involving consented 5- and 6- year olds and 12- and 13- year olds residing at Kaitaia, Kaikohe, Moerewa, Kawakawa and Dargaville.  The survey's aim is to assess the oral health status of these age groups in these towns.

Dr Gowda said, "The results released today, are for baseline and two year follow up epidemiology data on the levels of dental disease of children in Kaitaia, Kaikohe, Kawakawa, Moerewa and Dargaville".

The first data collection coincided with the introduction of water fluoridation in Kaitaia and Kaikohe in April 2007.  A second set of data was collected two years later during which time the towns of Kaitaia and Kaikohe reticulated water supply had remained fluoridated.  Comparisons could then be made between children who had been living in fluoridated and non-fluoridated areas during this period.  Kawakawa, Moerewa and Dargaville's water supplies remained unfluoridated during this period.

Oral Health Adviser to Northland DHB, Dr Neil Croucher says, "The strengths of the survey was that it followed a very robust methodology, gained full ethics approval and was carried out to international research standards."

Among the study's strengths was the comprehensiveness of the data collection (with caries data collected at surface level rather than at tooth level, as is the norm for caries data on New Zealand children), and that the examinations were conducted under consistent conditions in school dental clinics by calibrated dentists. Calibration testing proved that all four dentists involved with the survey were examining children's teeth accurately and consistently.

Weaknesses of the study identified were the less-than-ideal implementation of the community water fluoridation intervention, which meant that the fluoride levels generally remained below the optimal fluoride level of 0.7 to 1.0 ppm.  Another was the relatively low participation rate in Kawakawa/Moerewa during the 2009 data collection process.  This came about because of difficulties in obtaining written consent from parents and has probably affected the representativeness of the 2009 Kawakawa/Moerewa sample.

"Whilst there were some weaknesses identified in the study, they have not distracted from being able to conclude, that there were some beneficial oral health effects observed in the children who lived in areas that were fluoridated", said Dr Croucher.

Research shows that water fluoridation is safe and effective and is a proven public health measure that will reduce dental disease levels by up to 30%.  Oral health will improve in both adults and children, but young children and adolescents will enjoy the biggest benefits.

The report will be published in a reputable dental journal in 2010.  The wider research community and public will then be able to see the results and conclusions of this small but significant piece of survey work from the Far North of New Zealand.

The full report is available here: Far North Pre and Post Flurodation Report 598.17 Kb

For further information, please contact:

Fleur King
Public Relations Manager
Northland District Health Board 
Phone: (09) 430 4101 ext 3315
Mobile: 021 730 543

About Northland DHB Oral Health

Because Northland's children have one of the worst rates of dental decay in the country (nearly twice the national average), improving oral health is one of the top priorities for the Northland District Health Board.

Fluoridation is seen as the single most effective public health measure to prevent tooth decay and improve oral health over a lifetime, for both children and adults including our older people and so Northland DHB continues to advocate for the introduction of water fluoridation into Northland's reticulated water supplies.

Oral health teams are constantly promoting the importance of good oral health in communities which included those participating in the survey.  They promote such things as the importance of brushing teeth twice a day with adult strength fluoride toothpaste and encourage healthy eating and drinking regimes for the whole Whanau within the home.  All these activities help to reduce the chances of getting tooth decay.

Maori health providers also have specific programmes which focus on improving the health status of the entire Whanau, including adults.

Ends.