1 If X is a topological (or metric) space and M is a metric space, then the set of all bounded continuous functions from X to M forms a metric space if we define the metric as above: d (f, g) = sup x in X d (f (x), g (x)) for any bounded continuous functions f and g.
Invisalign is orthodontic appliance, so since orthodontic treatment is allowed as an FSA expense, Invisalign is covered. Different companies have different rules concerning amounts set aside and the timing of how funds are used for orthodontics.
The American Academy Of Orthodontists (AAO) recommends that most children should have an orthodontic assessment by age 7. With studies have shown that braces are more frequently applied to children at a later date (11-13) than the younger prepubescent (8-10) bracket.