Anatomical analyses of mandibular structure using three-dimensional facial ct for effectiveness and prevention of complications in genioglossus advancement

Abstract

Genioglossus advancement (GA) is one of popular procedure for the treatment of obstructive sleep apnea (OSA). This procedure is usually performed with mandibular osteotomy and advancement of genial tubercle (GT). The purposes of this study were to measure and analyze the position and dimension of GT, mental foramen (MF) and accessory mental foramen (AMF). And to make a reference in designing a location of the osteotomy during GA. Two hundreds and ten patients were included who performed 3D facial CT and the genial tubercle and mental foramen were evaluated in the CT. Subjects were divided into 4 groups by genders and skeletal type. Seven variables were measured, including: (1) height of GT (GTH); (2) width of GT (GTW); (3) distance from apices of lower incisors to superior border of GT (Li-SGT); (4) distance from inferior border of GT to inferior border of mandible (IGT-IBM); (5) thickness of anterior mandible (MT); (6) distance from symphysis of mandible to MF (S-MF); and (7) distance from superior border of GT to inferior border of mandible (SGT- IBM). In addition, the presence of AMF was analyzed. All the parameters showed big personal differences. There was no differences in GTW and Li-SGT among groups ( p > .05). Class I male showed longer GTH, MT and SGT-IBM than class I female ( p < .05). IGT-IBM and S-MF were longer in class II male than in class I female ( p < .05). Li-SGT showed personal variation with less than 7 mm in 62 cases, 7–10 mm in 122 cases, and more than 10 mm in 26 cases. IGT-IBM also showed variation with less than 10 mm in 61 cases, more than 10 mm in 149 cases. AMF were observed in 14 patients. The osteotomy for effective GA without dental complication may not be possible in some patients because of short Li-SGT. AMF were observed in some patients. The variable position and dimensions of the GT, MF and AMF among patients suggest the need for 3D facial CT before attempting GA to treat OSA. These findings may be helpful for the surgeons to design the osteotomies in the anterior mandible for the treatment of OSA. Financial Disclosure Information: The authors have no funding or financial relationships to disclose. Conflicts of interest: The authors have no conflicts of interest to report.