Can my veneers be filed at the top edges, and did the dentist take off too much too during prep? (photo)

Of course your veneers can be reshaped, but greater that 0.5 mm of shortening will depend on the size of the veneer relative to your underlying tooth structure.  This would need to be determined on x ray because reshaping them too much can compromise the integrity of the veneered tooth and predispose the veneer to cracking, chipping or coming off.  In the event that they cannot be reshaped, you can expect the dentist to recommend replacing them.In regards to your preps, they appear very short to me.  Almost as if they've actually been broken off.  The distal one (closest to the back of your mouth) is longer than the one in the front of it, but they are both pretty short and less than optimal in my opinion.  I can not say that this was your dentist's fault because I don't know the size and condition of the tooth prior to being prepped.  If her prepped in that short, he may have had a great reason to do so.Veneers are what I do, so follow me if you have more specific questions.Sarah Thompson, DMD

Yes, porcelain veneers can be adjusted and reshaped.  We do this all the time.  An experienced cosmetic dentist should be able to reshape your veneers where you think they are too long, too thick, or otherwise bigger than you want.  He will use a very fine diamond drill, followed by other polishing instruments to put back the smoothness and shine where he adjusted.