tongue numbness

Two weeks ago I had a temporary crown put on a lower right molar.  The Dentist had to give me several injections because I could feel the drill on the remaining filling. (Very Painful)  My tongue is still very numb as though I just had a shopt of novacane.  This is very annoying.  I have called the Dentist office three times already and they just keep sayingit will go away.  I wonder?....  I had a wisdom tooth pulled over twenty years ago and still have numbness in my tongue from that also. What do you think?  Is there anything that can make this go away?