| Field | Value |
|---|---|
| ID | OA-0188 |
| Type | component |
| Category | component |
| Fixed/removable | fixed (inserted into brackets) |
| Primary function | deliver continuous force for tooth movement |
| Uses TADs | no |
The archwire is the primary working element of fixed orthodontic therapy. It runs continuously through all bracket slots and molar tubes, and through its tendency to return to its pre-formed arch shape, it delivers the forces that move teeth into alignment. Treatment typically progresses through a wire sequence: light-force flexible NiTi rounds (e.g., 0.014" or 0.016" CuNiTi) for initial leveling and alignment → larger NiTi rects for torque expression → stainless steel rects (0.019×0.025" SS) for controlled space closure and finishing. Heat-activated NiTi wires deliver consistent light forces across a wide range of deflection.
high deflection; initial alignment
The archwire is the active engine of fixed orthodontic therapy. All tooth movement in a banded/bonded case is ultimately mediated by archwire force. Treatment is organized around a deliberate wire progression: clinicians start with light, flexible wires that can deflect around severely misaligned teeth without causing root resorption or patient discomfort, then move to stiffer wires as alignment improves and more precise force control is needed.
Stage 1 — Initial leveling and alignment: Round NiTi (0.014" or 0.016") or CuNiTi. Superelastic NiTi delivers light continuous forces across wide deflections; ideally suited for engaging crowded or rotated teeth. Heat-activated CuNiTi (Ormco Copper NiTi) activates at mouth temperature for consistent, patient-friendly force.
Stage 2 — Torque expression: Rectangular NiTi (0.016×0.022" or 0.017×0.025"). The rectangular cross-section engages bracket walls to express torque prescription while retaining the NiTi flexibility needed for residual alignment. The wire must fill enough of the bracket slot to transmit torque efficiently — a 0.016×0.022" wire in a 0.022" slot has measurable torque play.
Stage 3 — Space closure and finishing: Stainless steel rectangular (0.019×0.025" in a 0.022" slot). Stiff wire eliminates flex and allows precise detailing, controlled tipping and torque during space closure, and stable finishing mechanics. TMA (beta-titanium) is sometimes preferred at this stage for its intermediate stiffness and springback, particularly during torque correction.
Wire choice depends on slot size (0.018" vs 0.022" system), treatment stage, and patient tolerance. In self-ligating systems, the interaction between wire and slot is different — lower friction at initial stages allows smaller wires to slide freely, which affects sequencing. Clinicians prescribing custom arches (e.g., expanded coordination, tip-back bends) require stainless steel that can be bent and hold shape.
Rectangular NiTi should not be placed before adequate leveling — the torque expression in a severely rotated dentition can create undesirable tipping. Over-deflection of NiTi wires risks permanent deformation and inconsistent force delivery. Poking wire ends are a common patient complaint; distal ends should be cut flush with the molar tube.
No lab fabrication. Archwires are manufactured products; labs bend custom archwires only for specialty applications (e.g., utility arches, TPA wires, lingual archwires).
Appliances that incorporate this component. ★ = fabricated by Clear Fusion Lab.
high springback, light continuous force
0.017×0.025"); light force with 3D control
(0.019×0.025" SS); high stiffness for torque delivery and detailing
NiTi and SS; used in space closure or bite correction stages
temperature for consistent force delivery
Ormco](https://www.ormco.com/solutions/archwires/)
PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC3713252/)