A novel technique for malar eminence evaluation using 3-dimensional computed tomography.

Abstract

Objective: To describe a novel method to locate the malar eminence using 3-dimensional computed tomography (3D-CT), and a new axis system for evaluation of malar eminence symmetry.

Methods: A retrospective case series was carried out in 42 disease-free white adult patients. The 3D-CT reconstructions of the face were obtained, and the soft-tissue maxillozygion was used to locate the malar eminence. Other skeletal and soft-tissue landmarks (frontozygomatic suture, zygion, and orbitale) were evaluated. A patient-oriented axis system was constructed using 3 sagittal midline landmarks (nasion, subspinale, and basion). Coordinates were obtained for each landmark, and symmetry was evaluated.

Results: Twenty-one men and 21 women with mean ages of 41.1 and 41.3 years, respectively, were included. The malar eminence was easily localized using the 3D-CT technique for soft-tissue maxillozygion identification. Clinical asymmetry at the level of the soft-tissue maxillozygion was 40.5% (95% CI, 25.0%-56.0%). Other landmarks showed a prevalence of clinical asymmetry ranging from 24.0% to 50.0%.

Conclusions: The malar eminence can be easily and precisely located using the 3D-CT soft-tissue maxillozygion landmark. A reliable patient-oriented axis system can be defined using nasion, subspinale, and basion. The prevalence of malar eminence asymmetry in our study was 40.5%.