In fact the buccal plate is found to be lost when the tooth is extracted.  Osteotomy is initiated as palatal as possible apical, but the occlusion dictates the coronal end of the osteotomy should be buccal, leaving the buccal gap ~ 2 mm for bone graft.  The initial osteotomy (18 mm deep) appears to be close to the Incisive Foramen (Fig.3 blue dashed line).  The nasal floor appears to be intact when the drill is removed.  Subsequent osteotomy is adjusted so that the apical end of the osteotomy moves distal; when a 3.8x15 mm dummy implant is partially placed, there is clearance (Fig.4).

Proximity to Nasal Floor Last Next

Xin Wei, DDS, PhD, MS 1st edition 06/14/2018, last revision 06/14/2018