I recently had crowns replaced.  My dentist did a terrible job (colour,
shape..).  He agreed to replace them for me at no cost.  However, I
have lost all confidence in him as I do not find I was treated well
during this process.  He was very short with me throughout and did not
seem to care that they looked terrible. I don't even think that he put
on the crowns that I asked for.  Instead of having him fix them, I am
thinking of going to a CD and starting over.  My insurance has already
covered half of the cost of my crowns, but I have not yet payed the
other half.  Is it acceptable for me to not pay my dentist the other
half, or to ask for a refund of my insurance claim?  I do not want him
to be angry because he agreed to redo the work, but I cannot take the
chance that they will be a mess again.