THEY COME OUT TWICE A DAY

She takes them out only just twice a day 
There is no alternative and no other way 
Brushes them and cleans them up so white 
Does this routine both morning and night 

Fortunately I'm not around when all this takes place
I am out of the house at a rather brisk pace 
What may you ask am I referring to ?
For those seeking the answer here's another clue 

Without them she would find eating so much grief
I am referring of course to my wife's shiny false teeth
On reflection her false teeth don't really matter to me
I am sure I will be the same when I'm ninety three