Abstract
On the basis of previous findings, the effectiveness of a tea drinking program for caries prevention was tested in the primary schools of two typical Japanese farm villages for five years. Caries lesions on the pit/fissure (CF) and approximal sites (CA) were detected with the point of a No. 1 sewing needle by clinical criteria. The average number of carious lesions in both villages decreased in the first program year and reduction rates were almost constant thereafter. The reduction rates averaged 22.1% in CF and 26.1% in CA.
The program was evaluated from three angles, accessibility, availability, and acceptability. The monetary accessibility was considered very good because the above reduction rates were attained by the expense of only 1.5 yen for a cup of Bancha tea. Yearly production of Bancha in Japan would cover about 4.5 times more children.
In order to assess the objective acceptability, a new scale called the epidemiological susceptibility of the caries risk (ESF and ESA) was derived from the caries experience (CF and CA) divided by the caries risk which was half the number of existing teeth (D) multiplied by the dentitional age of the permanent teeth (T) of a child. The reduction rate of the susceptibility of the caries risk averaged 19.5% in ESF and 21.3% in ESA respectively. No signs of the mottling such as discoloration and disfiguration of the teeth were found on the lower front teeth.
It was stressed that dental caries produced by multifactorial causes should not be prevented by use of a single agent, but accomplished by a combination of multiple anticaries agents in order to avoid overdosage.
