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Enamel tufts are hypomineralized ribbon-like structures that run longitudinally to the tooth axis and extend from the dentinoenamel junction (DEJ) one fifth to a third into the enamel. They are called ‘‘tufts’’ due to their wavy look within the enamel microstructure. Biomechanically, enamel tufts are ‘‘closed cracks’’ or defects which, in their manner of propagating, act to prevent enamel fractures. This aspect of them is being studied to see how to make more fracture-resistant materials. However, they can also form without stress during enamel development. Enamel tufts are most common in the enamel of molars of animals that crush hard food objects, such as nuts (crushed by apes) and shellfish (crushed by sea otters). ==Microstructure== Each tuft consists of several unconnected leaves that start near the dentinoenamel junction. These defects as they pass through the enamel rods to the surface become progressively more fragmented and fibrillar. Scanning electron micrography finds that there are two kinds: one that is continuous with the enamel-dentine membrane at the dentinoenamel junction and that is acid-resistant, and another that is made up of empty spaces between the prisms and hard walls covered with organic matter. Enamel tufts are particularly common on low-crowned, blunt-cusped molars used in crushing; these are called "bunodonts". 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「enamel tufts」の詳細全文を読む スポンサード リンク
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