Figure 3: Case  2: (a1) upper part of the palatal canal over calcification managed by ultrasonic instrument before CBCT scanning (red arrow). (a2) Calcification of palatal canal (red arrow). (a3) Canal under calcification (red arrow). (b1)–(b3) Determination of depth in buccolingual direction and BLIA. (c1)–(c3) Determination of depth in mesiodistal direction and MDIA. (d) Radiograph before operation. (e) Affirmation of working length. (f) Canals after filling and temporary restoration.