When designing a custom zygomatic arch implant, the primary goal is usually not projection but controlled lateralization of the arch to create the desired increase in upper facial width while maintaining a natural skeletal contour.
Key Design Parameters
1. Amount of Width Increase
This is the most important variable.
Typical augmentation:
- 3–5 mm per side: subtle widening
- 5–8 mm per side: moderate widening
- 8–12 mm per side: significant widening
- >12 mm per side: aggressive widening, usually reserved for very narrow faces
Because width increases on both sides, a 7 mm implant per side creates approximately 14 mm of total bizygomatic width increase.
2. Location Along the Arch
The implant can emphasize:
Anterior arch
- Near the malar prominence
- Blends with cheek augmentation
- Creates more three-quarter-view definition
Middle arch
- Maximum widening effect
- Often the ideal location for skeletal expansion
Posterior arch
- Extends toward the root of the arch near the ear
- Produces a broader upper-face frame
- Must be designed carefully to avoid visibility in thin tissues
3. Shape Profile
A custom implant can be designed as:
Uniform width increase
Original arch —–
Implant effect =====
Result: consistent widening
Central flare
/\
—-/ \—-
Most projection occurs in the middle of the arch.
Posterior flare
—-\____/
Creates width farther back toward the temporal region.
4. Vertical Position
The implant can:
- Stay centered on the arch
- Add slight superior fullness
- Add slight inferior fullness
Most aesthetic designs remain centered to preserve natural anatomy.
5. Edge Transitions
One of the most important features of custom design.
The implant should:
- Feather gradually into native bone
- Avoid abrupt step-offs
- Extend sufficiently beyond the area of maximal augmentation
A well-designed implant is often almost invisible on CT except at the area of maximum projection.
Stand-Alone vs Combined Designs
Pure Arch Implant
Used when:
- Cheek projection is already adequate
- Face is narrow
- Goal is width only
Front view:
| |
/ \
/ \
After widening:
| |
/ \
/ \
Malar-Arch Implant
Most common custom design.
Advantages:
- Adds anterior cheek projection
- Adds lateral width
- Creates a continuous cheekbone contour
This avoids the appearance of having a prominent arch but a flat anterior cheek.
CT-Based Design Considerations
When designing from a 3D CT:
- Measure current bizygomatic width.
- Evaluate temporal hollowing.
- Determine cheek projection relative to orbital rim.
- Assess soft-tissue thickness over the arch.
- Simulate different lateralization values.
- Ensure the implant does not encroach on the temporalis muscle origin.
The best custom designs are usually judged from:
- Frontal view.
- Three-quarter view.
- Skeletal overlay measurements.
The actual implant often looks surprisingly small on the computer model; even a 5–7 mm lateral displacement of the arch can produce a noticeable increase in facial width.
Dr. Barry Eppley
Plastic Surgeon