Darker Permanent Teeth?

Teeth are comprised of three basic layers. In the center is the pulp, which contains the live tissues of the tooth: the nerve and blood supply. The middle layer is dentin and the outer layer is enamel. Both dentin and enamel come in a range of shades including grays and yellows, but dentin is usually the darker of the two substances. Often, the tooth appears more yellow toward the gumline because the enamel is thinner there and less able to mask the dentinal color. Permanent tooth enamel is semi-translucent, so the dentinal color shows through in the body of the tooth. Sometimes, the edges of the teeth even look bluish because light is actually going right through the structure. However, in primary teeth, the pulp is very large and the dentin and enamel layers are thin. The enamel in primary teeth is also more opaque, due to a less organized crystalline structure. This does a better job masking color in the dentin. The opacity also allows more light to be reflected to the eye, making the tooth appear whiter.

- Ellen Standefer McOmie, D.M.D.