Aim: To examine the influence of water fluoridation, and socio-economic deprivation on tooth decay in the permanent dentition of 12 year old children.
Setting: The North of England, fluoridated Newcastle and non-fluoridated Liverpool. A total of 6,638 children were examined.
Outcome measures: Multiple Regression analysis of fluoride status, mean electoral ward DMFT in 1992/93 and ward Townsend Scores from the 1991 census.
Results: Social deprivation and tooth decay were significantly correlated in areas with and without water fluoridation. Multiple linear regression showed a statistically significant interaction between ward Townsend score, mean DMFT and water fluoridation, showing that the more deprived the area the greater the reduction in tooth decay. At a Townsend score of zero (the English average) there was a predicted 37% reduction in decay in 12-year-olds in fluoridated wards.
Conclusions: Tooth decay is strongly associated with social deprivation. The findings confirm that the implementation of water fluoridation has markedly reduced tooth decay in 12-year-old children and that socio-economic dental health inequalities are reduced.