What is the whitest most natural looking emax crowns?

Determining the proper shade to pick for your new crown or veneers depends on how many teeth you are having work on and what your treatment goals are.
If you are having a single front tooth fixed, you are really limited on matching the porcelain to the teeth on either side. In this situation, I find it very helpful for my patients to meet with the ceramist who will be making the porcelain. Even though we take extensive high resolution digital pictures for shade matching, nothing gives the results of actually meeting with the lab in person.
If you are having more than a single tooth restored, than you have more freedom in choosing a different whiter shade. Usually, the more teeth you have restored, the less obvious a different shade would look. 
Color varies from person to person and in different lightening environments. Generally, If you have darker skin or for women who wear darker shades lipstick, color will look whiter than someone who has pale skin or wears natural color lipstick. So whats natural on you may look super white on someone else.
According to the 2 most used shade guides, B1 is the whitest natural shade on the Vita shade guide, where as 1M1 is the most natural on the Vita 3D guide.
If your having difficulty in selecting the perfect color between a couple of different options, I would always choose the lighter color.

Hi:The whitest emax crown is OM1.  However, how natural it looks it depends on skin tone, how many is being done.Best,Dr. Maddahi