Are the lines running down the root of a fossilized shark tooth natural to the tooth?

Kainantu

On the very outside of a tooth is a very hard substance called enamel. Enamel is the hardest substance in the human body, harder even than bone. It gains its hardness from tightly packed rows of calcium and phosphorus crystals within a protein matrix structure Inside this is another solid substance called dentine. Dentine is slightly softer than enamel, with a structure more like bone. It is elastic and compressible in contrast to the brittle nature of enamel. Dentine is sensitive. It contains tiny tubules throughout its structure that connect with the central nerve of the tooth within the pulp. Dentine is a ‘live’ tissue. Furthur inside is a soft substance called pulp. This is composed of blood vessels and nerve tissue which decay when a tooth is removed. If there are “tubules”, in other words tiny tubes in the dentine then my guess is that this is what you are looking for , and are thus natural. http://www.mydr.com.au/default.asp?article=3728 Aug 28 04, 3:56 AM