Can I Change for Veneers Having Already the Crowns?

While in theory a veneer COULD be placed over some crowns, the fee is the same as replacing the existing crowns.  Replacement would be best, especially since you are reporting pain.  It is possible that the nerve of one or more teeth is involved and should be addressed first, then new all porcelain crowns should be placed.  

When done right, all porcelain crowns CAN look fantastic and very natural.

Unfortunately, as you've already heard, you cannot replace a crown with a veneer. The lesson to be learned, however, is that not every dentist can do cosmetic dentistry. Also, remember: "You get what you pay for!". True cosmetic dentistry requires time, expertise, and the use of an excellent cosmetic laboratory, all of which cost precious dollars. If you do chose to have the crowns redone, shop around for quality, not price. Don't accept the final crowns until youy are very happy with the temporaries. Also insist on seeing the permanent crowns on your teeth with a "try-in paste" and make sure you LOVE them before allowing the final bonding or cementation.

Unfortunately once you have crowns you cannot go back to veneers, but All Porcelain Crowns can look as good as veneers if the are done well. Many of the cases that I do are combination cases with crowns next to veneers and you cannot tell which tooth was treated with a veneer or a crown.  What you have to realize is that the tooth structure underneath the crown or veneer will severely influence the final look of the crown or veneer.  If we are trying to make a significant color change for dark stained teeth the porcelain will need to be more opaque and not as transparent.  You may have a difficult case to treat.  Find a cosmetic dentist on AACD.com and get a second opinion.  Sorry for your trouble.

in cosmetic dentistry there are several solutions, depends on how much tooth surface we have, and also the brand of the porcelain, this will aloud us to work with the translucent material, making them look very natural,and more even, about the other teeth that do not have crowns ,they can be treated too with veneers or crowns, this is determined clinically.

Once you place a crown you can not go back and veneer same teeth. The tooth preparation of a crown entails removal of tooth stricture all around the tooth. Veneers are prepped only on a front portion of the tooth. So, once you have tooth reduction on a part of your tooth, you can not undo it .

All porcelain crown look can look  Awesome. So, if you are not happy with the result, you have to see whether the teeth were properly prepped, or the best porcelain material used. Is there a bite issue involved that has not been addressed. And a lab tech who can fabricate a nice looking crowns.

Good luck.