External Reference Nasal Pin for Orthognathic Maxillary Positioning: What Is the Proper Method of Placement?

The depth of penetration of an external reference nasal pin should be limited to a maximum of 10 to 12 mm from the STN. Initial skin penetration should begin immediately caudal to the STN, and the pin should be directed in a caudal direction to avoid inadvertent entrance into the ACF, as well as to facilitate a relatively safe penetration into the nasal cavity, if the maximum depth is excessive.