the process of cutting teeth is ordinarily called teething or dentition. there are two dentitions, the fist produces the primary teeth, also known as the deciduous, temporary, or milk teeth, and the second produces the permanent teeth. there are twenty primary teeth: four incisors,two canines and four molars in each jaw. the incisors are the front cutting teeth, the two in the middle are called central incisors, and those on either side are called lateral incisors. outside these are the canine teeth which are sharp, pointed, and able to tear food. beyond the canines are the molars or grinding teeth. the arrangement of teeth is the same in the upper and lower jaws, and on the right and left sides.
the second permanent set of teeth contains thirty-two teeth. twenty of these gradually replace the primary dentition. the permanent dentition starts at about six or seven years or older. this dentition begins with the appearance of the fist permanent molars and afterwards other permanent teeth are cut, including the central and lateral the incisors, the fist and second premolar, the canines, and second molars. the premolar which replace milk molars have two cusps on the crown and are also known as the bicuspids. the third molar teeth, the wisdom teeth, may appear between the ages of seventeen and twenty-five or late, or not at all.
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