Anterior superior alveolar artery and horizontal maxillary osteotomy

The aim of this study was to elucidate the location of the anterior superior alveolar artery relating to horizontal maxillary osteotomy.Fourteen hemifaces of 7 Korean adult cadavers were studied. Three horizontal cuts were made at the level of the anterior nasal spine (ANS), halfway between ANS and distal end of nasal bone (DNB), and a lower quarter from ANS to DNB. The location of the canalis sinuosis (CS) was measured on a rectangular coordinate. The x axis was a horizontal (cross) line on the lower border of the piriform aperture. The z axis was at the lateral border of the piriform aperture vertical to the x axis, and the y axis was perpendicular (anterior and posterior) line at 0 point of x and z axes. Blocks including 3 levels were decalcified, cut in 10-μm thickness, and stained with hematoxylin and eosin. Specimens were observed under a light microscope.Canalis sinuosis was found in all 14 hemifaces and ran in a curvilinear course along the piriform aperture. At the ANS level on the z axis, CS was located at 0.8 (1.8) mm medial to the y axis and 2.0 (0.9) mm posterior to the x axis. At a lower quarter from ANS to DNB, CS was located 1.6 (0.9) mm lateral to the y axis and 1.60 (0.8) mm posterior to the x axis. At halfway from ANS to DNB, CS was located 2.6 (1.3) mm lateral to the y axis and 1.70 (0.5) mm posterior to the x axis. In all histology specimens, vessels and nerves were found in small bony canal near the anterior wall of the maxilla. Arteries are well identified by their thick smooth muscle layer.In performing the horizontal maxillary osteotomy, surgeons should be aware of the presence of CS, which contains the anterior superior alveolar artery within 2 to 3 mm along the piriform aperture.