Three-dimensional analysis of facial asymmetry after zygomaticomaxillary complex fracture reduction: a retrospective analysis of 101 East Asian patients

Abstract

Background:The zygomaticomaxillary complex (ZMC) has a protruded, convex shape and plays a vital role in determining the contour by affecting the width of the middle face. This study aimed to evaluate the efficiency of ZMC fracture reduction and explore detailed directions for outcome improvement. Methods: We conducted a retrospective study of patients diagnosed with unilateral ZMC fracture who underwent ZMC reduction surgery at a single hospital between January 2015 and May 2020. The primary outcome variable was facial asymmetry using the difference in the bilateral malar eminence (ME) position measured by computed tomography scan. The 3-dimensional distance (IA, asymmetry index) and the distance in each dimension, Dx (anteroposterior distance), Dy (mediolateral distance), and Dz (superoinferior distance) were compared. Results: A total of 101 patients with ZMC fractures and 54 non-fracture patients were enrolled in the study. The mean age of the study sample was 43.49 years (control sample, 43.35 years), and the male-to-female ratio was 66.3:33.7 (control sample, 64.8:35.2). There were 53 and 48 patients with right and left ZMC fractures, respectively. The IA was not statistically different between the two groups. In terms of position in each dimension, only Dx was significantly different between the two groups. Conclusion:The results show that overall facial asymmetry was recovered after ZMC reduction, but in certain dimension significant difference in ME position has still remained. For further improvement, treatment should be performed to relieve malar depression in the anteroposterior dimension.

The divided zygoma: a meta-analysis of its prevalence with a review of the literature

“…This knowledge can be especially important in patients with facial trauma, particularly fractures of the buccal surface of the zygomatic bone shaft, as the zygomatic bone is the most prominent part of the facial skeleton [19,31]. After zygomaticomaxillary complex fracture all patients have performed the 3-dimentional analysis of the degree of recovery of malar asymmetry [3]. This 3D image is essential before reconstruction operation and the DZ could be seen in the frontal view, which could be misunderstanding.…”

Application of Computer-Aided Design and Individualized Templates for Bilateral Zygomaticomaxillary Complex Fractures

“…Some studies suggested that intraoral incisions and small local incisions can meet the surgical requirements. 32,33 However, bilateral ZMC fractures are usually accompanied by full-face fractures, which are often complicated with comminuted fractures. For the ZMC fracture with obvious displacement and comminuted fractures, the fracture site cannot be fully exposed at the small incision, and the fracture site can be maximally exposed at the coronal incision combined with other incisions, which is one of the foundations of accurate reduction.…”

“…Some studies suggested that intraoral incisions and small local incisions can meet the surgical requirements 32,33 . However, bilateral ZMC fractures are usually accompanied by full-face fractures, which are often complicated with comminuted fractures.…”

Proposal for a modified classification of isolated zygomatic arch fractures

“…The zygomatic arch is a cylindrical, thin, and long bridge-like structure that is structurally vulnerable to local trauma; fractures commonly result from both high- and low-velocity forces [ 2 ]. Zygomatic arch fractures often occur as part of zygomaticomaxillary complex fractures, which account for approximately 25% of all facial bone fractures, whereas isolated zygomatic arch fractures comprise 10% of all zygoma fractures and 5% of all facial fractures [ 3 – 5 ]. Zygomatic arch fractures cause esthetic problems due to the facial asymmetry resulting from lateral facial flattening and depression in the affected area and functional problems due to coronoid impingement [ 1 , 3 , 4 ].…”