Archwire sequences as companies and practitioners use them.
Severe crowding
Sequential ligation: engage the centrals first and the rest passively; ligating every tooth at once gives only part of the effect.Watch out · 1Upper incisors from the front. Left: sequential ligation — the centrals are tied in first and the displaced laterals left passive, the wire resting by their brackets untied; ligating every tooth at once gives only part of the effect. Right: a piggyback .014 NiTi over a stiff steel base, tied into the one displaced tooth while the base holds the arch.
What changes
Sequential ligation: engage the centrals first and the rest passively; ligating every tooth at once gives only part of the effect.
A piggyback .014 NiTi over a stiff steel base for one displaced tooth.
Watch out
Expect roughly double the alignment time — about +20% per millimetre of irregularity.
Lacebacks from the first wire; reverse-curve bends from the .018 steel if the bite deepens.Watch out · 2
Deep bite
Lower reverse-curve NiTi (16×22 or 17×25) once the arch is level, or hand-bent reverse curve in the lower steel wire.Watch out · 3
Open bite
Get the arch form first, then vertical or box elastics on steel only.Watch out · 2
Class II
Conventional twin brackets: Class II elastics from the .016 steel, or only after the upper 19×25 steel. Damon: light Class II elastics from day one on the .014 CuNiTi.Watch out · 2
Class III
Class III elastics only after a .016 round steel is in (prevents incisor extrusion); camouflage retroclines the lower incisors on round .018 steel.Watch out · 1
Impacted or ectopic canine
Open the space first with a coil on .016/.018 steel; pull with a .012/.014 NiTi piggyback or an auxiliary over a rigid base of at least .018 steel.Watch out · 2
Reduced periodontium and adults
Lighter forces throughout: a .012 or .014 starter, elastics delayed to the second visit, intermittent light forces.Watch out · 1
Reference dated 2026-10-19.
Upper segment, front to the right, first premolar extracted. Top: lacebacks from the first wire, molar to canine. Middle: canine-first retraction keeps more anchorage — about 60:40, front teeth moving back to back teeth moving forward. Bottom: en-masse retraction of the front teeth is about 50:50 but avoids deepening the bite. Bars and arrows to that split.
What changes
Lacebacks from the first wire; reverse-curve bends from the .018 steel if the bite deepens.
Consolidate on 16×22 SS, close on 17×25 or 19×25 SS with a chain or NiTi coil, lower arch first.
Canine-first retraction keeps more anchorage — about 60:40, front teeth back : molars forward; en-masse is about 50:50 but avoids deepening the bite.
Watch out
Never close on NiTi.
Which steel wire to close on is contested — 16×22, 17×25 or 19×25; choose one and keep it.
Sources (3)
PractitionerL0276
TextbookB0208 p.570
TextbookB0050 p.97
Left, both arches unrolled: once the arch is level, a reverse curve in the LOWER wire only (its relaxed front lies gingival, so the incisors intrude); the upper wire carries none — an upper reverse curve flattens the smile arc. Right, from the side: the alternative, anterior bite turbos bonded on the palatal faces of the upper incisors, which reduced the overbite as much and about 1.7 months faster in the one head-to-head trial.
What changes
Lower reverse-curve NiTi (16×22 or 17×25) once the arch is level, or hand-bent reverse curve in the lower steel wire.
Anterior bite turbos open the bite as much and faster; mini-screw intrusion gives true intrusion.
Band or bond the second molars when running a reverse curve.
Watch out
No reverse curve on the upper arch — smile arc.
No reverse curve in high-angle faces — intrude instead.
Reverse-curve NiTi proclines lower incisors; a torque-free steel reverse curve does not.
Both arches unrolled, front to the right, the front teeth apart. Get the arch form first, then box elastics on steel only (struck inset: never on NiTi, where the light wire just bends). Prefer intruding the back teeth to extruding the front — posterior bite blocks or composite buildups on the lower molars (arrows: the molars intrude).
What changes
Get the arch form first, then vertical or box elastics on steel only.
Intrude the buccal segments rather than extrude the front: posterior bite blocks or composite buildups on the lower molars, overcorrect the vertical.
Mini-screw full-arch intrusion on 17×25 TMA with tip-back and constriction bends when the skeletal pattern demands it.
Watch out
Box elastics never on NiTi — only on 18×25 / 19×25 steel.
No trial guides the wire choice here.
Sources (3)
PractitionerL0287
TextbookB0032
CompanyDamon treatment protocol sheets
Both arches unrolled, front to the right, the upper arch ahead (Class II). The elastic runs from the upper canine down and back to the lower first molar: it pulls the upper front teeth back and the lower molar forward (arrows). Its vertical pull extrudes both ends and tips the occlusal plane (dashed, angle enlarged) — pair it with a reverse or accentuated curve or an anchor bend. Pre-torqued (+20°) wires keep upper incisor torque and limit lower proclination.
What changes
Conventional twin brackets: Class II elastics from the .016 steel, or only after the upper 19×25 steel. Damon: light Class II elastics from day one on the .014 CuNiTi.
Pre-torqued (+20°) wires counter the elastics' side effects: upper incisor torque kept, lower proclination limited.
Fixed functional (Forsus-type): minimum 17×25 SS in .018 or 19×25 SS in .022, usually ligated on 18×25, worn three to four months.
Watch out
Pair elastics with a reverse or accentuated curve or an anchor bend — they extrude and tip the occlusal plane.
Avoid Class II elastics in high-angle faces or with proclined lower incisors.
Sources (4)
PractitionerL0261
PractitionerL0284
PractitionerL0287
CompanyDamon treatment protocol sheets
The Class II figure reflected about the occlusal plane, point for point: a Class III elastic runs from the lower canine to the upper first molar, pulling the lower front teeth back and the upper molar forward, and its vertical pull extrudes both ends and tips the occlusal plane the other way (angle enlarged). Class III elastics only after a .016 round steel is in, which prevents incisor extrusion. Damon: the +20° pre-torqued wire goes in inverted for Class III.
What changes
Class III elastics only after a .016 round steel is in (prevents incisor extrusion); camouflage retroclines the lower incisors on round .018 steel.
Damon: the +20° pre-torqued wire goes in inverted for Class III. Another company keeps the lower arch at .020 or smaller.
Watch out
Watch lower anterior torque throughout.
Sources (4)
PractitionerL0311
TextbookB0050 p.97
CompanyDamon treatment protocol sheets
CompanyDentsply GAC In-Ovation clinical white paper
Upper segment, front to the right, the canine high. Open the space with a coil on steel, then pull the canine with a .012/.014 NiTi piggyback over a rigid base of at least .018 steel, which holds the neighbours level. Struck inset: never engage the high canine in the light continuous wire — it intrudes the neighbours (the roller-coaster). Drop back to NiTi once the canine is 80–90% erupted.
What changes
Open the space first with a coil on .016/.018 steel; pull with a .012/.014 NiTi piggyback or an auxiliary over a rigid base of at least .018 steel.
Drop back to NiTi once the canine is 80–90% erupted.
Watch out
Never engage the high canine in the light continuous wire — it intrudes the neighbours (roller-coaster).
Light, flexible NiTi base wires have devitalized lateral incisors.
Sources (4)
TextbookB0034
TextbookB0204
PractitionerL0302
PractitionerL0309
Left: reduced periodontium — the bone crest (shaded) lies far apical of the cement–enamel junction (dashed: a normal crest), so the same force loads less support. Right, to scale: lighter forces throughout — a .012 or .014 starter — and the working wire downgraded to 16×22 steel instead of 19×25 (struck): no heavy 19×25 on a tooth with bone loss.
What changes
Lighter forces throughout: a .012 or .014 starter, elastics delayed to the second visit, intermittent light forces.
Working wire downgraded to 16×22 SS instead of 19×25 — less friction, less load on the ligament.
