After veneer revision, front teeth are darker in certain lighting. Should I just have those 2 replaced? (photo)

Based on your photos, your veneers look really nice in bright light, but only slightly dimmer in dim light, as you've described.  The slightly darker appearance is likely due to the material that was used.  I understand that all of the veneers are likely the same material, but the two central incisors are a lot bigger and thicker than your other veneered teeth, so they are less likely to allow low levels of light to pass through.  If you want to correct this, you can consider having the two front veneers redone to match in shade.  Personally, I do not think people will notice much, but it's all about what makes you happy, so it should be exactly like you want it.Veneers are what I do, so follow me to ask more questions.Sarah Thompson, DMD

In a perfect world, dentists could recreate the teeth with enamel and dentin.  However, the best tools we have to work with are porcelain.  However, porcelain is not enamel and dentin, and thus under different lighting conditions may look different.  This concept is called metamerism, and there is a long explanation of it in the web reference below.One thing I see in the second photo, is that your lip hangs down more than normal over your front two teeth, and that, in itself, will make the teeth look darker.  Anything in a shadow (your teeth from your lip) will appear darker (darker, lower value).What might be the answer you are looking for (other than the lip shadow effect just mentioned) is to have the crowns and veneers replaced with a more opaque porcelain, which will appear lighter/whiter/higher value in darker lighting conditions. However, when doing that you lose some of the natural translucency that makes the teeth look more "real".  Thus, you may have to choose, whiter teeth or teeth that look more "real."

Dr Sherri Worth DDS on Veneers. They are a great restorative option. They are a fairly noninvasive and
conservative procedure that will last approximately 10 to 20 years.

There is a
possibility that the preps of the teeth themselves are darker on the two front
teeth and as a consequence they may show through the crowns in certain light,
especially if the crowns are all porcelain like EMAX or EMPRESS. If for example
you had root canal treatment on those two teeth, the preps of the actual teeth
under the crowns may have darkened over time, or you may have dark metallic
posts in those teeth. You may have to have new crowns with Zirconia veneered
with Porcelain.

If dark
tooth structure is not the issue, then the lab my have somehow made those two
crowns darker. You could try to have just those two replaced but that may make
matching the shade to the other crowns difficult. Although this can be done, it will be easier if the lab is available to match these crowns by being able to see your other front teeth in person. This can be done by the lab technician coming to your doctors office or by you visiting the lab that is doing the work.