You must be happy with the color of crowns you are having. That is why the dentist will have a consult with you regarding the final color you desire. Once the color is selected you get exactly that color YOU selected. Now if for any reason you do not feel comfortable with final color, ask your dentist if they can be altered, which may be additional cost.In general,the final color depends on 3 main factors: 1-The preparation of the teeth by your dentist2-The porcelain material selected, and 3-The artistic ability of the master ceramist!Some crowns such as empress may show a lot more translucency, compared to zerconia crowns or lava, which they reflect light, and they look whiter and more opaque. Having said that the shaping of your teeth by your cosmetic dentist is vital, for the ceramist to block out enough room for the final color of porcelain. You need to ask your treating dentist if he can brighten them a bit more, which that should be ok, but it will require a lot of time by ceramist, and the dentist.Best of luck,Dr Mobasser