Ivory

Ivory is a hard, white, opaque substance that is the bulk of the teeth and tusks of animals such as the elephant, hippopotamus, walrus, mammoth, etc. Prior to the introduction of plastics, it was used for billiard balls, piano keys, buttons and ornamental items. The word "ivory" was traditionally applied to the tusks of elephants. Plastics have been viewed by piano purists as an inferior ivory substitute on piano keys, although other recently developed materials more closely resemble the feel of real ivory.

Teeth and tusks

Teeth and tusks have the same origins. Teeth are specialized structures adapted for food mastication. Tusks, which are extremely large teeth projecting beyond the lips, have evolved from teeth and give certain species an evolutionary advantage. The teeth of most mammals consists of a root and the tusk proper.

Related Topics:
Teeth - Tusk - Mastication

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Teeth and tusks have the same physical structures: pulp cavity, dentine, cementum and enamel. The innermost area is the pulp cavity. The pulp cavity is an empty space within the tooth that conforms to the shape of the pulp.

Related Topics:
Pulp - Cavity - Dentine - Cementum - Enamel

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Odontoblasts line the pulp cavity and are responsible for the production of dentine. Dentine, which is the main component of carved ivory objects, forms a layer of consistent thickness around the pulp cavity and comprises the bulk of the tooth and tusk. Dentine is a mineralized connective tissue with an organic matrix of collagenous proteins. The inorganic component of dentine consists of dahllite. Dentine contains a microscopic structure called dentinal tubules which are micro-canals that radiate outward through the dentine from the pulp cavity to the exterior cementum border. These canals have different configurations in different ivories and their diameter ranges between 0.8 and 2.2 micrometres. Their length is dictated by the radius of the tusk. The three dimensional configuration of the dentinal tubules is under genetic control and is therefore a characteristic unique to the order.

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Tooth and tusk ivory can be carved into an almost infinite variety of shapes and objects. A small example of carved ivory objects are small statuary, netsukes, jewelry, flatware handles, furniture inlays, and piano keys. Additionally, warthog tusks, and teeth from sperm whales, orcas and hippos can also be scrimshawed or superficially carved, thus retaining their morphologically recognizable shapes.

Related Topics:
Netsuke - Warthog - Sperm whale - Orca

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