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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.
186 questions in 27 reviews · Orthodontics
current versionsNo studies 186 · 100%Ungraded 0 · 0%Very low 0 · 0%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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Superelastic NiTi arch wire vs Multistrand stainless steel arch wire Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
Facemask (RME) or modified facemask vs Other non-surgical orthodontic treatments (mini maxillary protractor, Pushing Splints, modified tandem, Reverse Forsus, reverse Twin Block, reverse chin cup, tongue appliance, Frankel III) Perceived need for surgery in adulthood · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | SoF3: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire Pain · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Pain: not reported | 0 studies | No studies |
Superelastic NiTi arch wire vs Conventional (stabilised) NiTi arch wire Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Time to alignment: not reported | 0 studies | No studies |
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | SoF5 (Facemask (Alt-RAMEC) vs facemask (RME)): Overjet - Not measured. | 0 studies | No studies |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
Surgically-anchored orthodontic treatment (miniplates) vs Untreated control (no treatment) Perceived need for surgery in adulthood · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | SoF2: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Time to alignment: not reported | 0 studies | No studies |
Superelastic NiTi arch wire vs Multistrand stainless steel arch wire Time to next/working arch wire · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | No studies reported time to next/working arch wire | 0 studies | No studies |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Time to next/working arch wire · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | No studies reported time to next/working arch wire | 0 studies | No studies |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Pain · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Pain: not reported | 0 studies | No studies |
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates) Perceived need for surgery in adulthood · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | SoF4: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Time to next/working arch wire · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | No studies reported time to next/working arch wire | 0 studies | No studies |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Time to alignment: not reported | 0 studies | No studies |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Alignment rate: not reported | 0 studies | No studies |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi) Time to alignment · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Time to alignment: not reported | 0 studies | No studies |
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi) Root resorption · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Root resorption: not reported | 0 studies | No studies |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Patient satisfaction · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Patient satisfaction: discomfort/pain (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No studies measured or reported this outcome | 0 studies | No studies |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Cost of treatment · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Cost of treatment was not investigated in any of the included studies. | NR | No studies |
Hawley removable retainer vs Clear plastic removable retainer Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Survival of retainers · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 1 RCT at 6 months found no difference (very low-certainty) | 0 studies | No studies |
Hawley removable retainer vs Clear plastic removable retainer Patient satisfaction: comfort (VAS, upper and lower arches) · People who had received fixed appliance orthodontic treatment · 12 months, upper and lower arches Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12 months; 1 RCT at 6 months: Hawley less comfortable (VAS MD -1.86, 95% CI -2.19 to -1.53; very low-certainty) | 0 studies | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Patient-reported need for analgesics · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Patient-reported need for analgesics | Not reported | NR | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Total number of orthodontic appliance adjustment visits during overall treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | No study reported on the influence of LLLT on the total number of orthodontic appliance adjustment visits to complete a course of treatment. | NR | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Duration of total overall orthodontic treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | No study reported on the influence of LLLT on the total overall orthodontic treatment duration. | NR | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Orthodontic tooth movement (OTM) during alignment stage · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Orthodontic tooth movement (OTM) during alignment stage | Not reported | NR | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Patient-reported need for analgesics · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Patient-reported need for analgesics | Not reported | NR | No studies |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 2 RCTs at 6 months found no difference (low-certainty) | 0 studies | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Total number of orthodontic appliance adjustment appointments during treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Total number of orthodontic appliance adjustment appointments required during treatment stage | Not reported | NR | No studies |
Full-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Patient satisfaction: discomfort/pain (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No studies measured or reported this outcome | 0 studies | No studies |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Survival: mean survival time (lower arch, months) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 2 RCTs at 24 months: earlier failures with fibre-reinforced composite (MD -1.48, 95% CI -1.88 to -1.08; very low-certainty) | 0 studies | No studies |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Adverse effects on oral health: Gingival Index (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 1 RCT at 6 months: higher gingival inflammation with fibre-reinforced composite (MD 0.59, 95% CI 0.13 to 1.05; very low-certainty) | 0 studies | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Harms and side effects arising during treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Harms and side effects | Not reported. None of the included studies assessed harms arising during the LED intervention. | NR | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Root resorption of the impacted canine or adjacent incisors and first premolars · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | The studies did not report adverse events. | 0 studies | No studies |
Any orthodontic (non-surgical) treatment to correct posterior crossbite or expand the top teeth vs No treatment or another orthodontic treatment Signs and symptoms of respiratory issues · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… Orthodontic treatment for posterior crossbites (2021) · Cochrane | no estimate extracted | 0 studies | No studies |
Extraction of the primary (baby) canine (single primary tooth extraction) vs No extraction (non-intervention control) Reported improvement in the position of the ectopic canine measured from radiographs · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | Improvement in the position of the ectopic canine was not extracted as a distinct outcome (alpha-angle was the trial's own outcome). | 0 studies | No studies |
Any orthodontic (non-surgical) treatment to correct posterior crossbite or expand the top teeth vs No treatment or another orthodontic treatment Quality of life · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… Orthodontic treatment for posterior crossbites (2021) · Cochrane | no estimate extracted | 0 studies | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Any other adverse effects, such as gingival disease and demineralisation · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | The studies did not report adverse events. | 0 studies | No studies |
Fixed tooth-borne expansion (Hyrax) vs Observation (no treatment) Canine expansion (inter-canine distance) · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… Orthodontic treatment for posterior crossbites (2021) · Cochrane | Not measured (SoF 3) | 0 studies | No studies |
Extraction of the primary (baby) canine (single primary tooth extraction) vs No extraction (non-intervention control) Time taken for the canine to erupt into the mouth · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | no estimate extracted | 0 studies | No studies |
Fixed tooth-borne expansion (Hyrax) vs Fixed tooth-tissue-borne expansion (Haas) Canine expansion (inter-canine distance) · Children and adults with a posterior crossbite, without a Class III skeletal relationship, cleft lip or palate (or… Orthodontic treatment for posterior crossbites (2021) · Cochrane | Not measured (SoF 5) | 0 studies | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Costs / cost-effectiveness · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | The studies did not report cost-effectiveness. | 0 studies | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Reported improvement in the position of the ectopic canine measured from radiographs · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | no estimate extracted | 0 studies | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Patient-reported outcome measures (PROMs), including quality of life and pain · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | no estimate extracted | 0 studies | No studies |