Guide To Orthodontic Archwires

Force Levels (Approximate unloading plateau forces in grams)

Clinical Decision Algorithm (What wire to use when?)

• Visit 1 → 0.014 or 0.016 Heat-Activated Cu-NiTi 35°C (most common worldwide)
• Visit 2–3 → 0.016×0.022 or 0.018×0.025 Thermal NiTi
• Rectangular phase → 0.019×0.025 Cu-NiTi or TMA (if torque needed early)
• Space closure / major mechanics → 0.019×0.025 or 0.021×0.025 SS with loops or posted
• Finishing → 0.019×0.025 or 0.021×0.025 TMA or SS with individual bends

Pro Tips from Board-Certified Orthodontists

• 35°C Cu-NiTi is the single most-used initial wire globally (2025 surveys).
• Never skip from round NiTi straight to 0.019×0.025 SS → torque expression too early → gingival recession risk.
• TMA is the only wire that allows true third-order bends without breaking.
• In aligner cases, 0.019×0.025 SS or TMA “overlay” wires are commonly bonded to attachments for heavy mechanics.