Cochrane · intervention · CD007859

Initial arch wires used in orthodontic treatment with fixed appliances

Liu, C, Wei, Z, Jian, F, et al. · Cochrane Database of Systematic Reviews · 2024 · Cochrane Library

Oral Health Orthodontics5 versionsAMSTAR 2: not assessed

Full textEvery question was extracted from the full review (methods and results), not only its Summary of Findings table.

Questions

34

current version

GRADE rated

12

No studies

16

Included studies

29

as reported

No studies 16 · 47.1%Ungraded 6 · 17.6%Very low 3 · 8.8%Low 7 · 20.6%Moderate 2 · 5.9%High 0 · 0%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Review question

Element	Planned (methods)	Found (results)
Population	Participants of any age with full-arch fixed orthodontic appliances on the upper arch, lower arch, or both. Excluded: concurrent palatal expansion or extraoral appliances, previous active orthodontic treatment, or relevant medical history.	1915 participants (2581 arches) from 29 RCTs; sample sizes 14 to 200 participants; 13 studies included children/adolescents and adults, 13 only children/adolescents, 2 only adults.
Intervention	Initial arch wire (one material, cross-sectional shape or size)	Materials evaluated: conventional and multistrand stainless steel; conventional, single-strand superelastic, coaxial/multistrand superelastic, ion-implanted superelastic, coated superelastic, thermoelastic (with and without copper) NiTi; and TiNbTaZr; in sizes 0.012 to 0.018 inch
Comparison	Initial arch wires (first arch wire inserted into the fixed appliance at the beginning of treatment; excludes later arch wires), compared in terms of: (1) material; (2) cross-sectional shape; (3) cross-sectional size	Comparators drawn from the same set of stainless steel and NiTi wire types and sizes
Outcomes	Primary outcomes: alignment rate (tooth movement over a period of time); incidence/prevalence and amount of root resorption. Secondary outcomes: time to next/working arch wire; time to alignment; pain (intensity on VAS or categorical scale, and duration; analgesic consumption)	Alignment rate (n=20); Root resorption (n=3); Time to next/working arch wire (n=2); Time to alignment (n=3); Pain intensity (n=13)
Study designs	Randomised controlled trials	Randomised controlled trials (n=29)
Timing	Not reported	3 days to 6 months

Search date: 2022-07-04. Databases: Cochrane Oral Health's Trials Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE Ovid; Embase Ovid; US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov; World Health Organization International Clinical Trials Registry Platform

Questions and results

Current version only

Superelastic NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Time to next/working arch wire same question in other reviews	No studies reported time to next/working arch wire	0 studies	No studies
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies
Time to alignment same question in other reviews	Cobb 1998 measured time to alignment but reported results only as graphs, with no numerical data	1 study	Ungraded
Pain day 1 7 to 14 days same question in other reviews	MD 2.68 [-1.38, 6.75] 2.68 [-1.38, 6.75] mm (VAS; superelastic higher)	2 studies · 127 participants	Low Downgraded: risk of bias, imprecision

Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 5 questions

Outcome	Effect	Evidence	Status / GRADE
Time to alignment same question in other reviews	Time to alignment: not reported	0 studies	No studies
Pain day 1 3 to 7 days same question in other reviews	MD 0.29 [-0.52, 1.10] 0.29 [-0.52, 1.10] mm (VAS; superelastic higher)	2 studies · 142 participants	Low Downgraded: risk of bias, imprecision
Time to next/working arch wire same question in other reviews	MD 0.40 [-0.10, 0.90]	1 study · 88 participants	Ungraded
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies
Alignment rate 5 to 10 weeks same question in other reviews	Conventional NiTi vs superelastic NiTi (O'Brien 1990; Ong 2011); not pooled due to clinical heterogeneity; little or no difference in alignment rate	2 studies · 124 participants	Low Downgraded: risk of bias, imprecision

Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 5 questions

Outcome	Effect	Evidence	Status / GRADE
Pain same question in other reviews	Pain: not reported	0 studies	No studies
Alignment rate 4 weeks same question in other reviews	MD 0.10 [-0.95, 1.15] 0.10 [-0.95, 1.15] mm/4 weeks (CuNiTi faster)	1 study · 66 participants	Very low Downgraded: risk of bias, imprecision
Time to next/working arch wire same question in other reviews	MD 0.00 [-0.51, 0.51]	1 study · 86 participants	Ungraded
Time to alignment (alignment rate ratio) 6 months same question in other reviews	HR 1.30 [0.68, 2.50]	1 study · 60 participants	Low Downgraded: imprecision
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies

Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 5 questions

Outcome	Effect	Evidence	Status / GRADE
Time to alignment same question in other reviews	Time to alignment: not reported	0 studies	No studies
Time to next/working arch wire same question in other reviews	No studies reported time to next/working arch wire	0 studies	No studies
Alignment rate 4 weeks same question in other reviews	MD -2.64 [-4.61, -0.67] -2.64 [-4.61, -0.67] mm/4 weeks	2 studies · 64 participants	Moderate Downgraded: imprecision
Pain same question in other reviews	Pain: not reported	0 studies	No studies
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies

Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 5 questions

Outcome	Effect	Evidence	Status / GRADE
Time to next/working arch wire same question in other reviews	MD 0.40 [-0.11, 0.91]	1 study · 86 participants	Ungraded
Time to alignment 16 weeks same question in other reviews	MD 0.5 [0.21, 0.79] 0.5 [0.21, 0.79] months	1 study · 32 participants	Low Downgraded: risk of bias, imprecision
Root resorption (reduction in root length) 16 weeks same question in other reviews	MD -0.05 [-0.14, 0.04] -0.05 [-0.14, 0.04] mm (root length reduction)	2 studies · 52 participants	Very low Downgraded: risk of bias, imprecision, inconsistency
Alignment rate 4 to 16 weeks same question in other reviews	MD -0.28 [-0.62, 0.06] -0.28 [-0.62, 0.06] mm/4 weeks	5 studies · 183 participants	Low Downgraded: risk of bias, imprecision
Pain day 1 7 days same question in other reviews	MD 6.96 [1.82, 12.10] 6.96 [1.82, 12.10] mm (VAS)	3 studies · 94 participants	Moderate Downgraded: imprecision

NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 5 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies
Pain 7 days same question in other reviews	Different sizes of NiTi wires (Alhaija 2021; Erdinc 2004); not pooled due to clinical heterogeneity; little or no difference at day 1. Erdinc 0.014 vs 0.016 inch higher pain at day 4 MD 5.00 (0.19 to 9.81) and day 6 MD…	2 studies · 149 participants	Low Downgraded: risk of bias, imprecision
Time to next/working arch wire same question in other reviews	No studies reported time to next/working arch wire	0 studies	No studies
Time to alignment same question in other reviews	Time to alignment: not reported	0 studies	No studies
Alignment rate same question in other reviews	Alignment rate: not reported	0 studies	No studies

Coated superelastic NiTi wire (BioCosmetic, Titanol, TP Aesthetic or Tooth Tone) vs A different coated superelastic NiTi wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 1 question

Outcome	Effect	Evidence	Status / GRADE
Alignment rate 8 weeks same question in other reviews	Four-arm study of different coated superelastic NiTi wires (Ulhaq 2017); reduction in LII over 8 weeks; no difference between the four groups (ANOVA P=0.627)	1 study	Ungraded

Superelastic NiTi arch wire vs Titanium-niobium-tantalum-zirconium (TiNbTaZr) arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 1 question

Outcome	Effect	Evidence	Status / GRADE
Alignment rate 8 to 12 weeks same question in other reviews	Superelastic NiTi (Sentalloy) vs TiNbTaZr (Gummetal) (Nordstrom 2018); LII change over 8 to 12 weeks; no clear difference (ANOVA P=0.6938)	1 study · 28 participants	Ungraded

Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi)

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB5 (current) · 3 questions

Outcome	Effect	Evidence	Status / GRADE
Alignment rate 6 weeks to 6 months same question in other reviews	Multistrand StSt versus other materials (conventional StSt, superelastic NiTi, thermoelastic NiTi); alignment rate not pooled due to clinical heterogeneity (Cobb 1998; Evans 1998; Quintao 2005; West 1995); results…	4 studies · 281 participants	Very low Downgraded: risk of bias, imprecision
Time to alignment same question in other reviews	Time to alignment: not reported	0 studies	No studies
Root resorption same question in other reviews	Root resorption: not reported	0 studies	No studies

Superelastic NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption	Root resorption: not measured	0 studies	No studies
Time to alignment	Time to alignment: not measured	0 studies	No studies
Pain day 1 14 to 15 days	MD 2.68 [-1.38, 6.75] 2.68 [-1.38, 6.75] mm (VAS)	2 studies · 127 participants	Moderate Downgraded: imprecision
Alignment rate between first molars 8 weeks	MD 7.5 [-11.27, 26.27] 7.5 [-11.27, 26.27] mm/8 weeks (faster)	1 study · 48 participants	Low Downgraded: imprecision

Thermoelastic (active martensitic/heat-activated) NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption	Root resorption: not measured	0 studies	No studies
Time to alignment	Time to alignment: not measured	0 studies	No studies
Pain	Pain: not measured	0 studies	No studies
Alignment rate between first molars 8 weeks	MD -8.78 [-27.79, 10.23] -8.78 [-27.79, 10.23] mm/8 weeks	1 study · 42 participants	Low Downgraded: imprecision

Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Time to alignment 16 weeks	MD 0.30 [-1.14, 1.74] 0.30 [-1.14, 1.74] weeks	1 study · 49 participants	Low Downgraded: imprecision
Alignment rate between canines about 5 weeks	MD 0.28 [-0.33, 0.89] 0.28 [-0.33, 0.89] mm	1 study · 40 participants	Very low Downgraded: risk of bias, imprecision
Pain day 1 7 days	MD -1.1 [-15.1, 12.9] -1.1 [-15.1, 12.9] mm (VAS)	1 study · 79 participants	Very low Downgraded: risk of bias, imprecision
Root resorption	Root resorption: not measured	0 studies	No studies

Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Time to alignment 16 weeks	MD -0.20 [-1.64, 1.24] -0.20 [-1.64, 1.24] weeks	1 study · 49 participants	Low Downgraded: imprecision
Pain	Pain: not measured	0 studies	No studies
Root resorption	Root resorption: not measured	0 studies	No studies
Alignment rate ratio (hazard ratio) 6 months	HR 1.3 [0.68, 2.50]	1 study · 60 participants	Low Downgraded: imprecision

Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Alignment rate between canines 12 weeks	MD -5.07 [-5.99, -4.16] -5.07 [-5.99, -4.16] mm/12 weeks (single-strand slower)	1 study · 24 participants	Moderate Downgraded: imprecision
Root resorption	Root resorption: not measured	0 studies	No studies
Pain	Pain: not measured	0 studies	No studies
Time to alignment	Time to alignment: not measured	0 studies	No studies

Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB4 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption	Root resorption: not measured	0 studies	No studies
Pain day 1 7 days	MD 7.0 [-12.56, 26.56] 7.0 [-12.56, 26.56] mm (VAS; superelastic higher)	1 study · 30 participants	Low Downgraded: imprecision
Time to alignment 16 weeks	MD 0.5 [-0.78, 1.78] 0.5 [-0.78, 1.78] weeks (superelastic longer)	1 study · 50 participants	Low Downgraded: imprecision
Alignment rate between first molars 8 weeks	MD 16.28 [-4.05, 36.61] 16.28 [-4.05, 36.61] mm/8 weeks (superelastic faster)	1 study · 46 participants	Low Downgraded: imprecision

Superelastic NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB3 · 3 questions

Outcome	Effect	Evidence	Status / GRADE
Tooth movement (alignment rate) 6 weeks to 6 months	Multistrand StSt vs NiTi (Cobb 1998; Jones 1992; West 1995); meta-analysis not possible; effect not estimated; trials reported different outcomes at different times with substantial clinical heterogeneity	3 studies · 174 participants	Low Downgraded: risk of bias, inconsistency
Pain intensity (VAS) day 1	Multistrand StSt vs superelastic NiTi (Jones 1992); pain VAS day 1 or day 7; meta-analysis not possible; effect not estimated	1 study · 42 participants	Very low Downgraded: risk of bias, imprecision
Root resorption	Root resorption: not reported by any included study	0 studies	No studies

Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB3 · 3 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption	Root resorption: not reported by any included study	0 studies	No studies
Pain intensity (VAS) day 1 7 days	Conventional NiTi vs superelastic NiTi (Fernandes 1998); pain VAS day 1; meta-analysis not possible (single study); effect not estimated	1 study · 79 participants	Very low Downgraded: risk of bias, imprecision
Tooth movement (alignment rate) 35 days	Conventional NiTi vs superelastic NiTi (O'Brien 1990); tooth movement over 35 days; meta-analysis not possible (single study); effect not estimated	1 study · 40 participants	Very low Downgraded: risk of bias, imprecision

Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB3 · 1 question

Outcome	Effect	Evidence	Status / GRADE
Alignment rate ratio (single-strand superelastic NiTi versus copper NiTi) 6 months	Conventional/copper NiTi comparison (Pandis 2009), grouped in this version under single-strand superelastic NiTi versus copper NiTi; alignment rate ratio not estimable in SoF	1 study · 60 participants	Very low Downgraded: risk of bias, imprecision

Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB3 · 2 questions

Outcome	Effect	Evidence	Status / GRADE
Alignment (mm per 12 weeks) 12 weeks	Single-strand superelastic NiTi vs coaxial superelastic NiTi (Sebastian 2012); alignment mm per 12 weeks; not estimable; coaxial superelastic NiTi induced greater tooth movement	1 study · 24 participants	Very low Downgraded: risk of bias, imprecision
Root resorption	Root resorption: not reported by any included study	0 studies	No studies

Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB3 · 1 question

Outcome	Effect	Evidence	Status / GRADE
Pain intensity (VAS) day 1 and day 7 (superelastic versus thermoelastic NiTi) 7 days	Superelastic NiTi vs thermoelastic NiTi (Cioffi 2012); pain VAS day 1 and day 7; not estimable	1 study · 30 participants	Very low Downgraded: risk of bias, imprecision

Superelastic NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB2 · 9 questions

Outcome	Effect	Evidence	Status / GRADE
Pain intensity (VAS) day 1	MD 5.30 [-7.74, 18.34] 23.7 mm (0.015 inch multistrand StSt) vs 29 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) day 5	MD 1.50 [-1.82, 4.82] 2.6 mm (0.015 inch multistrand StSt) vs 4.1 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) over 14 days	MD -0.40 [-3.36, 2.56] 6.1 mm (0.015 inch multistrand StSt) vs 5.7 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) day 2	MD -5.40 [-19.22, 8.42] 25 mm (0.015 inch multistrand StSt) vs 19.6 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) day 7	MD 0.70 [-0.57, 1.97] 0.5 mm (0.015 inch multistrand StSt) vs 1.2 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) day 4	MD 2.90 [-1.05, 6.85] 11.0 mm (0.015 inch multistrand StSt) vs 5.5 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Pain intensity (VAS) day 6	MD 1.70 [-1.26, 4.66] 1.2 mm (0.015 inch multistrand StSt) vs 2.9 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision
Alignment rate 6 weeks to 12 months	Cobb 1998: no statistically significant difference between three arch wires, reported as graphs only with no numerical data. West 1995: superelastic NiTi produced improved alignment in the mandibular labial segment…	2 studies · 185 participants	Ungraded
Pain intensity (VAS) day 3	MD -8.00 [-18.22, 2.22] 20.6 mm (0.015 inch multistrand StSt) vs 12.6 mm (0.014 inch superelastic NiTi)	1 study · 42 participants	Low Downgraded: risk of bias, imprecision

Thermoelastic (active martensitic/heat-activated) NiTi arch wire vs Multistrand stainless steel arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB2 · 1 question

Outcome	Effect	Evidence	Status / GRADE
Alignment rate 8 weeks	Evans 1998 (three-arm): no statistically significant difference between 0.0155 inch multistrand StSt vs 0.016x0.022 inch medium force active M-NiTi vs 0.016x0.022 inch graded force active M-NiTi.	1 study · 51 participants	Ungraded

Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB2 · 7 questions

Outcome	Effect	Evidence	Status / GRADE
Pain intensity (VAS) day 2	MD 1.20 [-9.63, 12.03] 36 mm (0.014 inch NiTi) vs 37.2 mm (0.014 inch superelastic NiTi)	1 study · 128 participants	Moderate Downgraded: risk of bias
Pain intensity (VAS) day 6	MD -0.50 [-5.39, 4.39] 8.8 mm (0.014 inch NiTi) vs 9.3 mm (0.014 inch superelastic NiTi)	1 study · 125 participants	Moderate Downgraded: risk of bias
Pain intensity (VAS) day 3	MD 4.00 [-4.91, 12.91] 24.8 mm (0.014 inch NiTi) vs 28.8 mm (0.014 inch superelastic NiTi)	1 study · 128 participants	Moderate Downgraded: risk of bias
Pain intensity (VAS) day 7	MD 0.40 [-3.81, 4.61] 6.7 mm (0.014 inch NiTi) vs 7.1 mm (0.014 inch superelastic NiTi)	1 study · 124 participants	Moderate Downgraded: risk of bias
Alignment rate (contact point movement) 35 days	MD 0.28 [-0.33, 0.89] 1.42 mm (0.016 inch NiTi) vs 1.7 mm (0.016 inch superelastic NiTi)	1 study · 40 participants	Moderate Downgraded: imprecision
Pain intensity (VAS) day 5	MD 1.30 [-4.32, 6.92] 11.4 mm (0.014 inch NiTi) vs 12.7 mm (0.014 inch superelastic NiTi)	1 study · 126 participants	Moderate Downgraded: risk of bias
Pain intensity (VAS) day 4	MD 1.60 [-5.68, 8.88] 16.7 mm (0.014 inch NiTi) vs 18.3 mm (0.014 inch superelastic NiTi)	1 study · 127 participants	Moderate Downgraded: risk of bias

Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire

Population: People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch)

CD007859.PUB2 · 1 question

Outcome	Effect	Evidence	Status / GRADE
Time to alignment (lower anterior arches) 6 months	HR 1.3 129.4 days (0.016 inch CuNiTi) vs 121.4 days (0.016 inch NiTi)	1 study · 60 participants	Moderate Downgraded: indirectness

Initial arch wire (a given material, cross-sectional shape or size) vs A different initial arch wire (different material, shape or size)

Population: Patients with upper and/or lower full arch fixed orthodontic appliances

CD007859 · 4 questions

Outcome	Effect	Evidence	Status / GRADE
Root resorption	no estimate extracted	0 studies	No studies
Time to next/working arch wire	no estimate extracted	0 studies	No studies
Pain intensity experienced by patients	no estimate extracted	0 studies	No studies
Alignment rate (speed of initial tooth alignment)	no estimate extracted	0 studies	No studies