How long does the numbness last after a dental procedure?

Depends on how much they shot you up with. Typically, after 24 hours your mouth should relatively be back to normal. No more fuzzy tongue and 3ft long chin.

It depends on where the injection was and what procedure was performed. Most dentist say that you should not be feeling the effect of the local anesthetic after 6 hours. If you had wisdome ( third molars) removed you may experience it for sometime if the nerve was bruised or damaged from the extraction.