P.289 Numerical study of the midface dislocation using flnite element method (FEM)

Abstract

Infraorbital blow-out fracture (IOBF) is an uncommon midfacial trauma, and impairs eyeball function and causes esthetic problems. The extraoral approach can lead to some complications such as scarring, ectropion, and entropion. The intraoral approach, such as a transantral approach, has advantages such as no visible scaring, it can be used to simultaneously treat a zygomaticomaxillary complex fracture (ZMCF), and the procedure is relatively easy.IOBFs were reduced from the maxillary sinus, and fixated internally using miniplates and screws with/without Medpor (Porex, Newnan, GA) via a transantral approach. We used this technique in 11 patients who had an inferior blow-out fracture. Patient's records and CT scans were reviewed.The mean age of the patients was 37 years (ranging between 15 years and 68 years). The mean follow-up period was 9.8 months, which ranged from 1 to 24 months. Before the operation, the patients had orbital symptoms: diplopia in 3 patients; enophthalmos in 4; and gaze limitation in 3. All the patients showed periorbital swelling and ecchymosis. After surgery, none of the patients had diplopia, gaze limitations, and enophthalmos. There were no orbital symptoms or sinus symptoms due to an infection or allergic reaction after surgery except in 1 patient. In 1 patient, maxillary sinusitis developed at 4 months after surgery which subsided with antibiotic therapy after plate removal.We think this technique offers an easy approach, and produces reliable, satisfactory results in IOBF.