Advertised Advantages of Lumineers
Lumineers are marketed as being both thinner and stronger than many other brands of porcelain veneers available on the market. The manufacturers use these selling points to state that Lumineers are the "no prep" veneer, meaning that the surfaces of the existing teeth do not have to be altered to place the Lumineers. With most other brands of veneers, a small portion of your natural teeth is shaved away, both to give the bonding agent a good surface to adhere to, and to make the veneers fit more naturally in your mouth. However, within the touted "strengths" lie Lumineers potential weaknesses.
The emphasis on "no prep" can imply that Lumineers are easy to place, and easy to get great results with. This is just not true. A dentist without the proper training in cosmetic dentistry should simply not place porcelain veneers of any kind, and many cosmetic dentists agree that the "no prep" veneers actually make it MORE difficult to get a beautiful, realistic result.
Additionally, many people who have had Lumineers placed without any preparation of their natural teeth complain that the Lumineers look and feel bulky. Lumineers also may create a small ridge right at the gumline. Over time, that ridge can attract plaque and stains, and cause irritation to the gums.
The most important point to take away from this discussion of Lumineers is that you should chose your cosmetic dentist with great care, and then let the dentist make a decision about what kind of veneers would work best for you.