Figure 5.

A. The bone cortical is removed with a curette under manual pressure, exponsing the apical region; B. With a slow rotating, number 1/2 spherical bur and abundant irrigation near the limit between the medial and apical thirds, a transversal groove around 1.0 mm deep is prepared following the limit between the medial and apical third; C. The fracture should be produced with the double-bezel chisel; D. After the fracture is completed, the separation of the apical root segment becomes clearly visible.