After 8 years of age, there is no further
risk of fluorosis (except for the third
molars) because the permanent tooth
enamel is fully mineralized. The vast
majority of enamel fluorosis is mild or
very mild and characterized by small
white striations or opaque areas
that are not readily noticeable to
the casual observer. Although this
type of fluorosis is of no clinical
consequence, enamel fluorosis has
been increasing in frequency over
the last 2 decades to a rate of
approximately 41% among adolescents
because fluoride sources are
more widely available in varied
forms.17 Moderate and severe forms
of enamel fluorosis are uncommon
in the United States but have both
an aesthetic concern and potentially
a structural concern, with pitting,
brittle incisal edges, and weakened
groove anatomy in the permanent
6-year molars.