Objective To assess the effectiveness of fluoride foam combined with health education for the prevention of early childhood caries.Methods A total of 3 000 children who attended one of over 190 kindergartens in Nanshan District of Shenzhen in September 2013 were included in the study.These children were randomly divided into 3 groups

1 000 children in each group.Children in group 1 received fluoride foam combined with health education for caries prevention

those in group 2 received health education alone

while those in group 3 received no preventive measures.The caries status was checked and recorded periodically from 2013 to2015.Meanwhile

the prevalence rate of caries were calculated among kindergarten kids in Nanshan District of Shenzhen during 2013-2015.Results The prevalence rate of caries were 40.30%

44.04%

and 45.56%in2013

2014

and 2015

respectively

with a significant increasing trend year by year（P<0.05）.In 2013 and2014

the prevalence rate of caries were similar among the 3 groups（P>0.05）.In 2015

however

significant differences were noted（P<0.05）;the prevalence rate of caries in group 1 was lower than that in group 2 or group 3

and the rate in group 2 was lower than that in group 3.In group 1

the prevalence rate of caries remained similar from 2013 to 2015（P>0.05）;while that in group 2 and group 3 varied significantly with year（P<0.05）

with an increasing trend year by year.Conclusion The prevalence rate of caries among preschool children in Nanshan District of Shenzhen tends to increase year by year

and fluoride foam combined with health education is effective in preventing early childhood caries.