produce toxicity, and slightly more than 2 ml may be a potentially lethal dose (PLD).
In this 10-kg child the STD (safely tolerated dose) would be 10 mg of F, the PLD 50
mg, and the CLD (certain lethal dose) 320-640 mg of F.
Toothpaste containing 1000 p.p.m. F will contain 1 mg of F in a gram or 1 inch (25
mm) of paste. Toothpaste tubes vary from 25 g to 140 g. Even if the larger tube was
completely swallowed the amount of F (140 mg of F) would still be less than the CLD
for the 10-kg child, but would exceed the PLD. A container of 120 tablets, each of 1
mg, would contain 120 mg of fluoride. Again, this would be within the CLD but
exceed the PLD. All containers with fluoride tablets should have childproof tops and
be kept out of reach of young children.
Acidulated phosphate-fluoride (APF) gels and foams are contraindicated in preschool
children.
290H
Fig. 7.5 Site-specific application of
fluoride varnish.7.6.2 Chlorhexidine gels
Clinical research in very young children is limited, but there is substantial agreement
that daily professional applications of chlorhexidine followed by applications every
few months can be significant in controlling caries. This probably results from
chlorhexidine's ability to reduce the levels of mutans streptococci in both saliva and
plaque.
7.6.3 Fissure sealants
Although not used routinely in the primary dentition, fissure sealants may be of value
on primary molars (especially second primary molars) where one or more primary
molars has already developed occlusal caries.
7.6.4 Toothbrushing
Plaque removal with a soft, small-headed toothbrush in combination with a suitable
fluoride toothpaste should start as soon as the child's first tooth erupts. Preschool
children need help from their parents if effective oral hygiene is to be maintained, so
parental involvement in oral hygiene instruction is essential. Some toddlers can be
resistant to parental (and professional!) attempts to brush their teeth. Parents should
be encouraged to persevere through such difficulties, ensuring that their child's teeth
are thoroughly cleaned at least once daily. Standing or kneeling behind the child in
front of the sink or mirror is often the easiest way to effectively brush a young