I had some dental work done last year and half of my face drooped for about a month afterwards - as in stereotypical image of a stroke.
I do have to have a LOT of anaesthetic for dental work as my nerves are connected between teeth, so they can numb my front tooth for example, and can feel the pain still 3 teeth back - something to do with nerve channels?
While the drooping slowly came right, that side is still less sensitive and I occasionally bite it and my lip on that side is a bit 'softer' looking.
Def call dentist though so they know what is going on with you, although likely not much they can do