<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">dentin</topic></authority><related type="narrower"><topic>ivory</topic></related><related type="other"><topic>dental enamel</topic></related><related type="broader"><topic>tooth components as material</topic></related><variant type="other"><topic>dentine</topic></variant> <note xml:lang="en"><![CDATA[ Material comprising the primary, bone-like structure of a tooth. Dentin is hard calcareous material, with less porosity and less organic matter than bone. It is generally covered with a protective enamel layer. Layers of dentin cover animal teeth (whale, hippopotamus, boar, etc.) and tusks (ivory, elephant, walrus, etc.).  ]]></note></mads>