Cochrane · intervention · CD003453

Orthodontic treatment for crowded teeth in children

Turner, S, Harrison, JE, Sharif, FNJ, et al. · Cochrane Database of Systematic Reviews · 2021 · Cochrane Library

Oral HealthOrthodontics2 versionsAMSTAR 2: not assessed
Full textEvery question was extracted from the full review (methods and results), not only its Summary of Findings table.
Questions
44
current version
GRADE rated
15
No studies
0
Included studies
24
as reported
No studies 0 · 0%Ungraded 29 · 65.9%Very low 15 · 34.1%Low 0 · 0%Moderate 0 · 0%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

ElementPlanned (methods)Found (results)
PopulationChildren (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth; studies with cleft lip/palate or other craniofacial syndromes excluded; studies with <80% of participants aged 16 or under excluded1512 participants randomised, 1314 analysed; mean age 7.6 to 15.3 years; 15 studies reported gender (male 23.3% to 58.8%)
InterventionFixed appliances and auxiliaries; removable appliances and auxiliaries; extractions (any intervention or combination, at any time during treatment)Fixed appliances and auxiliaries (n=20); Removable appliances and auxiliaries (n=2); Extractions (n=2)
ComparisonNo treatment, delayed treatment, placebo, or another active interventionNo active treatment (n=17); Minor interceptive procedures (n=1); Conventional brackets (n=5); Nickel-titanium archwires (n=3); Fixed appliances only (n=3); Passive self-ligating brackets (n=2); Multistranded stainless steel archwires (n=2); Stainless steel archwires (n=2)
OutcomesPrimary: Amount of crowding (mm or any index of malocclusion). Secondary: Size of the upper jaw (arch length); Size of the lower jaw (arch length); Upper incisors to maxilla; Lower incisors to mandible; Lower molars to mandible; Time to alignment; Time for ligation; Self-esteem; Participant satisfaction; Jaw joint problems. Other: Harms (health of the gums; damage to the teeth; pain including use of analgesia)Amount of crowding (n=24); Arch length (n=7); Time to alignment (n=8); Ligation time (n=1); Upper incisors to maxilla (n=3); Lower incisors to mandible (n=6); Lower molars to mandible (n=2); Harms (n=6)
Study designsRandomised controlled trials (RCTs) of orthodontic treatments to prevent or correct crowded teeth, comparing one intervention to placebo, no intervention or another crowding methodRandomised controlled trials (n=24)
TimingClinically important outcomes recorded at the most common endpoints reported for all ages19 different time points recorded across studies, from pre-treatment to 13-year follow-up

Search date: 2021-01. Databases: Cochrane Oral Health's Trials Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE Ovid; Embase Ovid

Questions and results

Show all 2 versions

Lower lip bumper vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
4 questions
OutcomeEffectEvidenceStatus / GRADE
Lower incisors to mandible at 6 months
6 months
MD 3.14 [1.73, 4.55]1 study · 34 participantsUngraded
Amount of crowding (change in mandibular incisor crowding) at 6 months
6 months
MD -4.39 [-5.07, -3.71]
-4.39 [-5.07, -3.71] mm
1 study · 34 participantsVery low
Downgraded: risk of bias, imprecision
Size of the lower jaw (mandibular arch length) at 6 months
6 months
MD 3.34 [2.71, 3.97]1 study · 34 participantsUngraded
Lower molars to mandible at 6 months
6 months
MD -0.91 [-1.58, -0.24]1 study · 34 participantsUngraded

Cervical pull headgear vs Minor interceptive procedures (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
4 questions
OutcomeEffectEvidenceStatus / GRADE
Size of the jaws (maxillary and mandibular arch length)
2 to 8 years
MD 1.98 [1.80, 2.16]1 study · 64 participantsUngraded
Amount of crowding (lower incisor crowding) at 2 years
2 years
MD 0.33 [-0.60, 1.26]
0.33 [-0.60, 1.26] mm
1 study · 64 participantsVery low
Downgraded: risk of bias, imprecision
Upper incisors to maxilla at 2 years
2 years
MD 4.5 [1.36, 7.64]1 study · 64 participantsUngraded
Lower incisors to mandible at 2 years
2 years
MD 1.4 [-0.42, 3.22]1 study · 64 participantsUngraded

Lower lingual arch vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
4 questions
OutcomeEffectEvidenceStatus / GRADE
Size of the lower jaw (mandibular arch length) at 1 year
1 year
MD 2.61 [1.83, 3.39]1 study · 30 participantsUngraded
Amount of crowding
1 year
SoF1: Amount of crowding - Not measured. The single study (Rebellato 1997) did not report the amount of crowding for this comparison.1 studyUngraded
Lower incisors to mandible at 1 year
1 year
MD 3.01 [1.71, 4.31]1 study · 30 participantsUngraded
Lower molars to mandible at 1 year
1 year
MD -1.11 [-1.51, -0.71]1 study · 30 participantsUngraded

Self-ligating brackets vs Conventional brackets

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
5 questions
OutcomeEffectEvidenceStatus / GRADE
Lower incisors to mandible (inclination, degrees)
post-treatment
MD 1.29 [-1.77, 4.35]1 study · 33 participantsUngraded
Time to alignment (days)
alignment
MD 89.64 [-45.89, 225.17]2 studies · 148 participantsUngraded
Amount of crowding (lower incisor crowding) at 10 weeks
10 weeks
MD -0.40 [-0.93, 0.13]
-0.40 [-0.93, 0.13] mm
1 study · 60 participantsVery low
Downgraded: risk of bias, imprecision
Time for ligation (seconds, to ligate six brackets)
during treatment
MD -78.8 [-81.86, -75.74]1 study · 60 participantsUngraded
Harms (discomfort, periodontal/gingival health, root resorption)
up to 9 months
No evidence of differences between self-ligating and conventional brackets for discomfort (Atik 2014, Miles 2010), plaque/gingival index and probing depth (Atik 2014), or maxillary incisor root resorption (Aras 2018).…3 studiesUngraded

Active self-ligating brackets vs Passive self-ligating brackets

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
2 questions
OutcomeEffectEvidenceStatus / GRADE
Time to alignment (days)
alignment
MD -13.11 [-28.76, 2.53]2 studies · 144 participantsUngraded
Amount of crowding (upper anterior crowding)
baseline
Only baseline upper anterior crowding reported (Pandis 2010a, n=70); evidence of baseline imbalance between groups (P=0.04); no post-treatment between-group crowding estimate reported.1 studyUngraded

Copper nickel-titanium archwire vs Nickel-titanium archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
3 questions
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (Little's Irregularity Index) at 12 weeks
12 weeks
MD 0.49 [0.35, 0.63]
0.49 [0.35, 0.63] mm
1 study · 66 participantsVery low
Downgraded: risk of bias, imprecision
Harms (discomfort)
after archwire change
No difference in overall discomfort levels between copper NiTi and NiTi archwire sequences (Ong 2011, 7-point Likert). Narrative; no pooled estimate.1 studyUngraded
Time to alignment (days)
alignment
MD -2.63 [-14.50, 9.24]2 studies · 191 participantsUngraded

Coaxial nickel-titanium archwire vs Nickel-titanium archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
1 question
OutcomeEffectEvidenceStatus / GRADE
Amount of tooth movement / reduction in crowding at 12 weeks
12 weeks
MD 6.77 [5.55, 7.99]
6.77 [5.55, 7.99] mm
1 study · 24 participantsVery low
Downgraded: risk of bias, imprecision

Nitinol archwire vs Titinol archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
1 question
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (change) up to 37 weeks
up to 37 weeks
MD -0.28 [-0.89, 0.33]
-0.28 [-0.89, 0.33] mm
1 study · 40 participantsVery low
Downgraded: risk of bias, imprecision

Nickel-titanium archwire vs Multistranded stainless steel archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
2 questions
OutcomeEffectEvidenceStatus / GRADE
Harms (pain)
first days
No difference in overall pain, but more pain with nickel-titanium at 12 hours and day 1 (morning, afternoon, bedtime) vs multistranded stainless steel (Sandhu 2013). Narrative; no pooled estimate.1 studyUngraded
Amount of crowding (change in mandibular crowding) at 8 weeks
8 weeks
MD 1.60 [-22.16, 25.36]
1.60 [-22.16, 25.36] mm
1 study · 25 participantsVery low
Downgraded: risk of bias, imprecision

Nickel-titanium archwire vs Stainless steel archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
1 question
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (change in mandibular crowding) at 8 weeks
8 weeks
MD -16.80 [-42.79, 9.19]
-16.80 [-42.79, 9.19] mm
1 study · 24 participantsVery low
Downgraded: risk of bias, imprecision

Multistranded stainless steel archwire vs Stainless steel archwire

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
1 question
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (change in mandibular crowding) at 8 weeks
8 weeks
MD -18.40 [-47.12, 10.32]
-18.40 [-47.12, 10.32] mm
1 study · 23 participantsVery low
Downgraded: risk of bias, imprecision

Lacebacks with fixed appliances vs Fixed appliances only (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
2 questions
OutcomeEffectEvidenceStatus / GRADE
Size of the lower jaw (arch length)
6 months
MD 0.83 [-6.41, 8.07]1 study · 62 participantsUngraded
Amount of crowding (change) at 6 months
6 months
MD -0.33 [-5.90, 5.24]
-0.33 [-5.90, 5.24] mm
1 study · 62 participantsVery low
Downgraded: risk of bias, imprecision

Vibrational appliance with fixed appliances vs Fixed appliances only / no vibrational appliance (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
4 questions
OutcomeEffectEvidenceStatus / GRADE
Harms (discomfort, pain intensity, analgesia use)
first week
No clear difference in discomfort/pain intensity or analgesia consumption between vibrational appliance and control (Miles 2012, Miles 2016, Woodhouse 2015; 100 mm VAS). Narrative; no pooled estimate.2 studiesUngraded
Amount of crowding (change in mandibular crowding) at 10 to 30 weeks
10 to 30 weeks
MD 0.24 [-0.81, 1.30]
0.24 [-0.81, 1.30] mm
2 studies · 119 participantsVery low
Downgraded: risk of bias, imprecision
Time to alignment (days)
alignment
MD -3.70 [-26.29, 18.89]2 studiesUngraded
Harms (orthodontically-induced inflammatory root resorption)
end of alignment
Using a vibrational appliance did not affect amount of root resorption vs control (Woodhouse 2015; 72 participants analysed). Narrative; no pooled estimate.1 study · 72 participantsUngraded

Schwarz appliance vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
4 questions
OutcomeEffectEvidenceStatus / GRADE
Upper incisors to maxilla (inclination, degrees) at 9 months
9 months
MD 0.33 [-2.26, 2.92]1 study · 28 participantsUngraded
Size of the lower jaw (mandibular arch length, change) at 9 months
9 months
MD 0.11 [-0.46, 0.68]1 study · 28 participantsUngraded
Amount of crowding (lower arch crowding, change) at 9 months
9 months (after 6 months treatment)
MD -2.14 [-2.79, -1.49]
-2.14 [-2.79, -1.49] mm
1 study · 28 participantsVery low
Downgraded: risk of bias, imprecision
Lower incisors to mandible (position, mm) at 9 months
9 months
MD 0.39 [0.11, 0.67]1 study · 28 participantsUngraded

Eruption guidance appliance vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
1 question
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (number of children with crowding, mandible) after 1 year
1 year
OR 0.19 [0.05, 0.68]
14 out of 22 children (control) vs 6 out of 24 children (experimental)
1 study · 46 participantsVery low
Downgraded: risk of bias, imprecision

Extraction of lower deciduous canines vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
3 questions
OutcomeEffectEvidenceStatus / GRADE
Lower incisors to mandible (inclination, degrees) at 1 year
1 year
MD 0.08 [-0.55, 0.71]1 study · 83 participantsUngraded
Amount of crowding (lower incisor crowding, change) at 1-2 years
1 to 2 years
MD -4.76 [-6.24, -3.28]
-4.76 [-6.24, -3.28] mm
1 study · 83 participantsVery low
Downgraded: risk of bias, imprecision
Size of the lower jaw (arch length, change) at 1 year
1 year
MD -2.73 [-3.69, -1.77]1 study · 83 participantsUngraded

Extraction of third molars (wisdom teeth) vs No active treatment (control)

Population: Children or adolescents (aged 16 years old or under) receiving orthodontic treatment to prevent or correct crowded teeth
2 questions
OutcomeEffectEvidenceStatus / GRADE
Amount of crowding (Little's Irregularity Index, change) at 5 years
5 years
MD -0.30 [-1.30, 0.70]
-0.30 [-1.30, 0.70] mm
1 study · 77 participantsVery low
Downgraded: risk of bias, imprecision
Size of the lower jaw (arch length, change)
5 years
MD 1.03 [0.56, 1.50]1 study · 77 participantsUngraded