ABSTRACT
Human dentition exists on both maxillary (upper jaw) and mandibular (lower jaw) bones, which develops in two stages: primary dentition (deciduous, transitory, milk, lacteal, baby dentition) including 20 teeth and permanent dentition ( secondary, successional dentition) including 32 teeth. These teeth are denominated as: central incisor (di1), lateral incisor (di2), canine (dc), first molar (dm1), second molar (dm2) for primary (deciduous) dentition and central incisor (I1), lateral incisor (I2), canine (C), first premolar (P1), second premolar (P2), first molar (M1), second molar (M2), and third molar (M3) for permanent dentition.1,2 The primary dentition com prises two incisors, one canine and two molar teeth, whereas permanent dentition has two incisors, one canine and three molar teeth and additionally two premolar teeth in each quadrant. There are four quadrants, each covering five teeth for primary dentition and eight teeth for permanent dentition; these are placed in an imaginary plus sign that separates the right and left teeth with a vertical midsagittal line, and upper and lower teeth by the horizontal occlusal line. The incisor tooth that is closest to the midline is called the central incisor, the teeth distal to the central incisors are the lateral and canine incisors. Similarly, both premolar and molar teeth are labeled according to the midsagittal guideline. The clos est teeth to this plane are labeled and ordered first, the teeth distal to the first are labeled second and the furthest teeth to the midsagittal plane are labeled third molars.3
