Morphology of the deciduous tusk (tush) of the African elephant (Loxodonta africana).

ABSTRACT

The tusk of the African elephant is preceded by a deciduous tooth generally known as the tush. Tushes from nine elephant fetuses and six calves younger than 1 year were exposed by dissection and described morphologically. All tushes consisted of a crown, root and pulpal cavity, the formation of which is completed soon after birth. They reached a maximum length of 5 cm, appeared not to erupt through the skin and were pushed aside and resorbed during enlargement of the distally located primordium of the tusk. Dental enamel, which covered the crown, could easily be removed and consisted of rods with an interwoven arrangement; the dentine-enamel junction was flat. Cellular cementum extended for variable distances over the crown and the dentine was tubular in nature. Although the tush apparently has no function, it provides the anlage and orientation for the development of its permanent successor.