After childhood, I have been OK with dentists until recently. I have developed Sudden Onset Adult Asthma and at the same time my throat (already sensitive after years of teaching) has become highly irritable to almost anything (including saliva) touching it in the wrong place. Lately a form of instant reaction has developed in which my whole throat clamps shut if anything it objects to - a bit of dust etc. hits it. Best they can come up with is an allergic reaction - but I can't breathe.
So, now I am very worried about the dentist. I broke a tooth many years ago, but it finally had to be extracted last year. Not nice - but trying to get an impression to make a replacement was far worse and I am now terrified t.b.h..