Despite the availability of free health dental service in Sri Lanka, the prevalence and
severity of dental caries among 6year old school children stand at a very high level
according to the results of national oral health survey in 1983/84, 94/95 and 2002/2003.
Professional fluoride varnish application has become popular as variety of studies has found
that it is an efficient method in reducing dental caries. The simplicity of its application
makes it very suitable and practical for use in dental clinics and outreach dental services,
especially in young children.
Aim of this study is to evaluate the cost effectiveness of 6 monthly application of sodium
fluoride varnish in prevention of dental caries in permanent incisors and molars in children
between 6 and 7 years in a suburban setting in Sri Lanka. This will be a double-blind,
randomized controlled trial. A sample of school children (6-7 years) will be randomized into
varnish and control groups. All the children will receive routine caries preventive measures
of oral hygiene instructions, dietary advice and professional cleaning. Children in varnish
group will receive fluoride varnish professionally applied after prophylaxis every 6 months.
Clinical examinations of all children will be performed at the beginning of the study and 1
year and 2 years later. All the caries at the dentinal level of both groups will be
stabilized with temporary restorations at the beginning. During this period, each school will
be visited four times at 6-month interval for recruitment, dental examinations, and fluoride
varnish applications. Recruited children will be randomly assigned to either a treatment (5%
NaF varnish) or a control group. Caries examinations will be conducted using the
International Caries Detection and Assessment System (ICDAS). The cost for the dental team's
school visits; cost involved in the treatment of dental caries throughout the course of the
study in both groups will be evaluated and compared at the end of the study. The sample size
is calculated as 160 each arm to detect 5% caries change with 80% power. Analysis The effect
of intervention will be measured by number of caries prevented. New caries in the usual care
and intervention group will be calculated after the completion of the study. The costs for
intervention will be estimated. The costs will be estimated for the dental material, time for
human resources and indirect costs.