e. Prophylaxis Pastes With Fluoride. A thorough prophylaxis removes a very
thin layer of enamel from the teeth. This layer is generally very rich in fluoride and
otherwise more highly mineralized than the deeper layers. Some researchers suggest
that if a prophylaxis is not to be followed by a topical application of a concentrated
fluoride solution or gel, a fluoride-containing prophylaxis paste should be used in an
effort to replenish lost fluoride. However, other researchers feel that fluoride
prophylaxis pastes are ineffective when used without a topical solution.
Fluoride solutions are toxic to the human body if ingested in large quantities.
They cause nausea if swallowed in small amounts, particularly in small children. Close
supervision and care must be taken when using these solutions clinically or when
prescribing them for home use. Many commercial preparations of fluoride
mouthwashes are now available over the counter at most drug stores. Patients should
be cautioned to follow the manufacturer's directions exactly.
3-20. OCCLUSAL SEALANTS
Although fluoride will drastically reduce the overall prevalence of dental caries, it
is least effective on occlusal decay. This is the area in which the occlusal sealants are
a valuable adjunct. With this method, the outermost layer of enamel is made receptive
to bonding by acid decalcification. The orifices of the pits and fissures are physically
occluded with a resin material rendering them immune to caries as long as the resin is
retained. Retention seems to be greater for premolars than molars and for mandibular
rather than maxillary teeth. It would seem that the concern about possible progression
of carious lesions isolated underneath sealant materials is unfounded. As long as the
sealant is intact, there is a progressive decrease in the number of viable bacteria under
the restoration and thus the carious lesion may become inactive. Occlusal sealant
application should be part of the preventive dentistry program.