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specialty

W-Arch

The W-Arch appliance, also called the Porter arch, is a stainless steel wire expander soldered to bands on the upper first molars. Made to your Rx and shipped in 10 business days or faster.

Expansion

W-Arch

You can order it as a fixed-removable that slides into sheaths on the first molar bands, so you can take it out to reactivate. With the right activation, it expands one side only. A quad helix adds four helical loops for flexibility, which the W-Arch leaves out.

Anchorage
Banded, upper first molars
Patient age
Mixed dentition
Correction
Dentoalveolar transverse
Compliance
None, activated chairside
3D printing
Available
Turnaround
10 business days or faster

When it’s the right call.

Use it when
Posterior crossbite in the mixed dentition
Unilateral expansion with the right activation
Cases where you want to remove and reactivate the wire
Slow expansion with no screw turns at home
Consider another appliance when
You want the flexibility of four helical loops See Upper Quad Helix
You need rapid skeletal expansion in a growing patient See Haas
You want a pin and tube driven by a coil spring See E-Arch

Options you can prescribe.

Fixed-removable

Slides into sheaths on the first molar bands.

Anchorage

Choose bands, ROC crowns, crowns or OnBRACE® (note OnBRACE® on the Rx). Also available 3D printed from your scan.

Still deciding which expander?

Suture maturity, tooth-borne or tissue-borne, banded or bonded, and whether the patient's parents can manage screw turns. Those narrow the choice quickly.

What every
W-Arch case needs.

Send these with the case and it goes straight onto the bench. If anything’s missing, we call you before we start.

Upper and lower digital scans, or stone models if you work on stone
The completed Rx sheet, with your design choices marked
Your requested return date, so we schedule the case back from it

Resources for the W-Arch

The Rx sheet, instructions for use and chairside guides, ready to download or share with your team.

More expanders.

View All Expanders
FAQ

Questions about the W-Arch.

Both are wire expanders on the upper first molars. The quad helix adds four helical loops for flexibility, and the W-Arch doesn't have them.

Yes. W-Arch and Porter arch are two names for the same appliance.

Yes. With the right activation, it gives unilateral expansion.

Yes, if you order it as a fixed-removable. It slides into sheaths on the first molar bands.

Haas, top view Distal Jet, top view MARPE 4 eyelet, front view

Send us your
next case.

Appliances that fit the first time and arrive on time.