Surgical access through the cortical bone to the roots of maxillary premolar.

The apex is exposed by removing the overlying bone. Before the introduction of ultrasonic retrotips, an osteotomy was necessarily large to allow the use of large instruments and to reach the palatal or lingual canals. The drawing show the use of the round surgical bur.

Black background.

1654 x 2244 pixels

14 x 19 cm (300 dpi)

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