Temporary Veneers Are So Bulky and Wide?

The main role of the temporaries is "work out the kinks", both in the bite and the look.  If you don't like the temps, you likely won't like the finals.  But you might.

I would ask to see the waxup.  As stated earlier, the temps should be made from THAT design, and should not feel bulky.

My suggestion is that you do not proceed with the permanent veneers until you are happy with the size and shape of your temporaries.  The main reason for the wax-up is to allow us to give you temporaries that  should give you an idea of what your permanents will look like.  If you dislike them that much you need to have a conversation with your dentist and clearly communicate what you are unhappy with.  This is the time changes can be made.  It is worth the time and effort to get this corrected now before the permanents are placed.  In the end, I'm sure that your smile will be stunning!

As the other practitioners have stated previously the wax-up should be done first to give you a very good idea how the final product will look. The temp veneers should have a very similar shape to what the final restoration should be. Make sure the look you want esthetically and functionally is what you get. Do not allow the finished product to be cemented unless you are satisfied with the veneers.