The 1st intraop PA is taken when the depth is reached with a 2.2 mm pilot drill (Fig.1 (yellow dashed line: superior border of the Inferior Alveolar Canal)).  The 2nd purpose of the PA is to make sure that the osteotomy is establish in the mesial slope of the socket (red dashed line). 

Slow Gentle Osteotomy 第二磨牙即种 Last Next

Xin Wei, DDS, PhD, MS 1st edition 07/30/2019, last revision 04/18/2021