Zygomatic arch reduction and malarplasty with multiple osteotomies: its geometric considerations.

BACKGROUND: The midfacial width is dominated by the lateral protruding degree of the zygomatic arch. The best way of narrowing the midface is to reduce the arch height and the arc length for patients with an overly curved lateral protruding zygomatic arch. The existing techniques for reduction malarplasty cannot change the degree of curvature of the zygomatic arch. We provide a new technique for efficient midfacial width reduction by multiple osteotomies at different sites on the zygomatic complex and bone resection at the most protruding middle part of the zygomatic arch. The amount of bone resection can be calculated with a simplified geometrical solution according to the desired reduction rate of the arch height.

METHODS: A digitalized CT image was used to estimate the arch height and the length of bone for removal from the zygomatic arch. A specific piece of bone was removed from the most protruding point of each zygomatic arch. Greenstick fractures were made at the anterior and posterior roots of the zygomatic arch. The open arches were rotated inwardly until both ends met.

RESULT: The arch heights of 1,020 sides of the zygomatic arch were reduced in a range from 3 to 11 mm. All the reduced zygomatic arches were reunited properly and healed solidly. The overall satisfaction rate was high.

CONCLUSION: This technique reduces the width of the midface by changing the degree of curvature of the zygomatic arch. The simplified geometrical calculation solutions are helpful in assuring the reunion of the zygomatic arch at a pre-designed lower arc height level after a calculated shortening of the arc length.

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