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.
While most people tend to associate orthodontics with children, adults are also prime candidates for treatment. Approximately 25% of all orthodontic patients are adults. Advances in technology and the introduction of more indiscriminate, clear braces make the benefits of orthodontics a must for any adult.