ele is "HE" not "SHE"!!!
In one of the sentences it said aparelho was braces, now it says device, how is that?
I think that it only means 'braces' like in dentistry, but they are usually fixed in a mouth and can't be put or placed on a table.
We have "non-fixed braces" [aparelho móvel]
Aparelho odontológico - braces
Can we say here " Ele põe o aparelho na mesa"? What is the difference between "colocar" and "pôr"?
Actually, they have the same meaning.