When my parents needed to watch DD many years ago, now granted this was at our house, the clinic we go to sent us a specific form to fill out, the form was also "valid" at the hospital for emergencies too.
So, I would recommend calling your pedi, and see if they have a form that would help to facilitate treatment if it is needed.
Please remember, while a hospital will treat someone in an emergency, i.e. an accident without a release, somethings do need to be treated that aren't emergencies, i.e. pink eye, ear infections etc.
Now - I would have never thought to include dental (and orthodontic) providers to. I'll file that one away in case DH and I are both out of town again.