I'm curious if anyone else has this problem? I went to the dentist today to have a crown, and after 4 shots I still wasn't numb enough for them to do the work. She started drilling and I could feel it, so she stopped and rescheduled. She ordered a "special" kind of numbing stuff to see if this will take affect. I have such a fear of the dentist because of this. Anyone else experience anything like this? She said this is rare, but there are others like me.