Dentists are strange people who derive an unusual pleasure from causing other people serious pain. They will all have strange regional accents which will make them incomprehensible to any human being not from Birmingham. This dialect barrier will be accentuated by the fact that many dentists wear "safety masks", supposed to stop the transmission of germs, but which many people rumour to hide the fact that the dentist in question is salivating hideously (or that they have filthy teeth).