D14

#14. The upper first premolar normally has two roots and two root canals. Occasionally only one root is present, but even then two canals are still often found. The root tips are very fine which may result in perforation even in a straight canal if a large apical open size is attempted. The roots are often equally long but 1 - 2 mm differences may occur. The root tips and apical canals may curve in the mesio-distal or bucco-palatal dimensions. Rarely, the upper first premolar has three roots and three root canals (= molarization) as with upper molars, although the roots are much finer and smaller.

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