Caries prevalence of preschool children in Baja, Hungary, in 1975 and 1982: effect of a supervised monthly NaF mouthrinsing program.

The aim of the study was 1) to compare the caries prevalence of preschoolchildren in Baja with data from 1975 and 2) to evaluate the effect of 0.2% sodium-fluoride mouthrinsings practiced during the last 4 yr. In 20 kindergartens of Baja 1462 children between 3 and 6 yr of age were investigated. All the children were participants in an oral hygiene motivation program and fluoride rinsings, performed generally monthly, but at least 10 times in a year. The dental investigations of the primary teeth were carried out by the same team as in 1975. The frequency of caries-free children increased from 18.8% in 1975 to 24.8% in 1982. The dmft mean values decreased only in the 5- and 6-yr-old children.

Fluoride-resistant acid phosphatase (FRAP) activity of nociceptive nerve terminals in the dental pulp.

Nerve fibers in the dental pulp of the lower molar teeth of the rat exert fluoride resistant acid phosphatase (FRAP) activity. FRAP-positive axons establish a three-dimensional nerve plexus within the pulp; the individual axons are very fine (calibre less than 1 micrometer) and only their varicosities measure 1...2 micrometer in diameter. Electron microscopically, FRAP-positive amyelinate axons containing lysosomes are partly embedded in Schwann cells. Removal of the cervical superior ganglion does not induce any alteration of FRAP-positive axons, while destruction of the Gasserian ganglion results in Wallerian degeneration. No FRAP-positive nerve fibers were found in rat incisors. Since, in the rat, only molar teeth are equipped with nociceptive terminals while continuously growing incisors lack pain fibers, it is concluded that FRAP-positive varicose axons in the dental pulp represent nerve endings of trigeminal primary nociceptive neurons.