Clinical Anatomy of the Skull Related to Maxillary Osteotomy in Koreans

Kim, Hee Jin; Choi, Jin Ho; Hur, Kyung Seok; Park, Hyung Sik; Chung, In Hyuk

Abstract

Maxillary osteotomy is a commonly performed maxillary surgical procedure for the correction of dentofacial deformities. LeFort I osteotomy necessitate seperation of the skeleton of the middle third of the face from its posterior attachments to the cranium. With conventional techniques, an osteotome is placed between the maxilla and pterygoid plates and tapped medially and anteriorly to separate the pterygomaxillary junction. To separate the pterygomaxillary junction safely, knowledge on the anatomical structures of the pterygopalatine fossa area is very important to surgeons. So, to clarify the anatomical structures as it relates to the surgical approach of the pterygomaxillary junction area, Korean skulls (male 110 sides, female 44 sides) were used. The results were as follows. 1. In Korean skulls, the height of the pterygomaxillary junction was 16.4 +/-3.9 mm on the right side and 16.5 +/-3.8 mm on the left side in males. In females, height of that was 14.9 +/-2.0 mm on the right side and 15.7 +/-2.4 mm on the left side. The width of the pterygomaxillary junction was 12.3 +/-2.0 mm on the right side and 11.8 +/-1.5 mm on the left side in males. In female skulls, the width of that was 11.4 +/-1.6 mm and 11.1 +/-1.3mm on the right and left side, respectively. The distance from the pterygomaxillary junction to the orifice of the greater palatine foramen was 10.4 +/-1.8 mm(the right), 10.4 +/-1.7 mm(the left) in males and 9.4 +/-1.6 mm(the right), 9.6 +/-1.5 mm(the left) in females. 2. The shape and location of the greater palatine foramen as it relates to the position of the maxillary molar teeth were investigated. The shape of the all greater palatine foramina was oval shape in which had long diameter antero -posteriorly. The greater palatine foramen was located at the palatal position of the maxillary third molar was the most commonly observed. And the prevalence in which the greater palataine foramen was located at the palatal position of the maxillary second molar and was located at the palatal position between the maxillary second molar and the maxillary third molar were 5.6 % and 18.5 %, respectively. In two cases, the greater palatine foramen were located at the palatal position of the distal aspect of the maxillary third molar. The mean distance from the greater palatine foramen to the posterior end of the palatine bone was 3.7 +/-1.3 mm(the right), 3.9 +/-1.4 mm(the left) in males, and 3.4 +/-1.2 mm(the right), 3.3 +/-1.2 mm(the left) in females. 3. As a surgico -anatomical data, the location of the pterygomaxillary junction related to the nasal floor and maxillary alveolar arch was observed. The height from the level of the the nasal floor plane to the superior border of the pterygomaxillary junction was 11.6 +/-3.8 mm (the right), 11.0 +/-3.4 mm(the left) in males and 10.8 +/-2.2 mm(the right), 10.7 +/-2.4 mm(the left) in females. Measuring value of the depth from the sagittal plane passing the outermost maxillary alveolar arch to the outer region of the pterygomaxillary junction was 7.1 +/-1.9 mm in right side and 6.9 +/-1.6 mm in left side. Taken all together, with regard to the morphology of the pterygomaxillary junction, pterygomaxillary dysjunction would be safely done with pterygomaxillary osteotome which has a width of 15mm in Koreans. And for the sake of surgical safety, osteotomy should be angled inferiorly from the zygomaticomaxillary crest.