It is very difficult to comment with out seeing the case But still ideall it is always better that the bite is raised before going for the crowns . That way they will last longer and aesthetically also good results can be given. But if your dentist is confident that by adjusting te position of crowns he can give them then you can think about that. In my pinion for best results bite should be raised before going for the crown.If you want to know more about the smile make over you can visit the folowing link on our website.....http://www.identalhub.com/articlecategory-cosmetic-dentistry-85.aspx