I fear the dentist mainly because of risking to get any form of hepatitis, mainly B or C . A friend's mother died from hep c and they presumed it was from the dentist and another person i know recently found out she has hep B and she only had her teeth fixed some months ago.
The problem is : it takes months for either virus to turn into the disease and in that time you "could have gotten it from anywhere" so some dentists or even doctors could skip a bit on the sterilzation methods because you can't prove it was from them.
I go to the dentist but not as much as i'd like to honestly, because of this fear.