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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.
830 questions in 43 reviews · Orthodontics
current versionsNo studies 186 · 22.4%Ungraded 410 · 49.4%Very low 122 · 14.7%Low 79 · 9.5%Moderate 30 · 3.6%High 3 · 0.4%
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 |
|---|---|---|---|
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi) Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 6 weeks to 6 months Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | 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 |
Facemask with rapid maxillary expansion (RME) vs Reverse Twin Block with lip pads and rapid maxillary expander (RME) Wits appraisal · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -1.85 [-3.18, -0.52] | 1 study · 26 participants | Ungraded |
Intervention NR Fluoride ion release · nCaF2-containing orthodontic adhesive (Yi 2024 [35]); significant increase up to 56 days vs control Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | no estimate extracted | 1 study | Ungraded |
Facemask (RME) or modified facemask vs Surgically-anchored appliance (miniscrews or miniplates) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.35 [-0.78, 0.07] | 4 studies · 143 participants | Low |
Adhesive flash-free ceramic brackets vs Adhesive precoated ceramic brackets Enamel demineralization (QLF ΔF) · Patients undergoing fixed orthodontic treatment · Baseline to debonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | ΔF values (T0-debonding) were not statistically significantly different between the groups. | 1 study · 50 participants | Ungraded |
Clearfil Protect Bond vs Transbond XT conventional adhesive White spot lesion rate and volume · Patients undergoing fixed orthodontic treatment · 8 weeks after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | There was no significant difference among the WSL rates of the Clearfil, Opal Seal, and Transbond XT adhesives (p > 0.05). | 1 study · 15 participants | Ungraded |
Transbond XT with 1% chitosan and 1% TiO2 nanoparticles vs Transbond XT adhesive Enamel mineral content · Patients undergoing fixed orthodontic treatment · 1 day, 2 months, and 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | There were no significant differences in enamel mineral content between the experimental group and control group at all time points. | 1 study · 24 participants | Ungraded |
Experimental adhesive containing ammonium-based methacrylate monomer (MADQUAT) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control Enamel remineralization / carious lesion development · Human enamel specimens around orthodontic brackets (in vitro) · biofilm cariogenic challenge 5 days, Overall Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | A study using an orthodontic adhesive containing ammonium-based methacrylate showed significant remineralization power compared with control adhesives [37]. | 1 study | Ungraded |
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire Pain day 1 · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 7 days Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | MD 6.96 [1.82, 12.10] | 3 studies · 94 participants | Moderate |
Hybrid Hyrax (RME) with miniscrews and Class III elastics vs Conventional Hyrax (RME) with miniscrews and Class III elastics Wits appraisal · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.28 [-1.08, 1.64] | 1 study · 35 participants | Ungraded |
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 |
Facemask (with frame internal fixation) vs Frankel III functional appliance ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.11 [-1.29, 1.07] | 1 study · 34 participants | Ungraded |
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) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.96 [-0.12, 2.04] | 4 studies · 136 participants | Very low |
Indirect bonding using flowable composite adhesive (Opal Bond MV) vs Direct bonding (conventional, Transbond XT) White spot lesion formation (QLF: fluorescence loss, lesion area) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · Before and after treatment (T0 to T1) Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Atilla 2020 (1 single-blind parallel RCT, 51 patients): the direct-bonding group had significantly greater loss of fluorescence and demineralization and larger lesion areas than the indirect-bonding (flowable… | 1 study · 51 participants | Ungraded |
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 1-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 1.77 [1.58, 1.96] | 1 study · 38 participants | Ungraded |
Hybrid Hyrax (RME) with miniscrews and Class III elastics vs Conventional Hyrax (RME) with miniscrews and Class III elastics ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.55 [-0.40, 1.50] | 1 study · 35 participants | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Incidence of new ICLs (proportion of subjects developing new lesions) · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During fixed orthodontic treatment (development of new lesions), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | Proportion 0.48 [0.33, 0.63] | 7 studies · 533 participants | Very low |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (proportion of tooth surfaces affected) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | Proportion 0.22 [0.14, 0.33] | 6 studies · 11583 participants | Very low |
Reverse Forsus vs Untreated control (no treatment) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 5.54 [4.40, 6.68] | 1 study · 22 participants | Ungraded |
Chin cup (600 g force) vs Chin cup (300 g force) ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.10 [-0.31, 0.51] | 1 study · 40 participants | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (proportion of subjects affected) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | Proportion 0.57 [0.48, 0.65] | 13 studies · 1448 participants | Very low |
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 |
Facemask 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) · 6-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | OR 3.34 [1.21, 9.24] | 1 study · 65 participants | Low |
One-step self-adhesive resin without a separate primer (GC Ortho Connect) vs Conventional multi-step adhesive systems (three-step Transbond XT; self-etch primer Transbond Plus) White spot lesion development (QLF: mineral loss, lesion area/depth, new lesions) · Patients undergoing fixed orthodontic (fixed appliance) treatment (adolescents and adults, ages 12 to 35) · 2 and 4 months Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Horan 2023 (1 three-arm RCT, 75 patients): the one-step adhesive without primer (GC Ortho Connect) had a significantly higher WSL incidence and larger, deeper lesions than both the three-step and self-etch systems… | 1 study · 75 participants | Ungraded |
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 |
Clearfil Protect Bond antibacterial fluoride-releasing primer vs Transbond XT conventional primer Bracket failure · Patients undergoing fixed orthodontic treatment · During orthodontic treatment Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | No statistically significant difference in bond failure rates was observed between quadrants bonded with Clearfil (CF) and those bonded with the conventional primer (p = 0.316). | 1 study · 35 participants | Ungraded |
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 |
TiO2-modified composite (1 wt.%) vs Control composite in contralateral quadrant Enamel demineralization (DIAGNOdent score) · Patients undergoing fixed orthodontic treatment · 1 to 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Mean readings were significantly greater on the control side than on the experimental side (p < 0.001) at all time points except at baseline. | 1 study · 40 participants | Ungraded |
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 |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Plaque accumulation (Plaque Index) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · Range 1 to 18 months (maximum time-point per study), Study design: randomized controlled trials White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -1.79 [-3.63, 0.04] | 3 studies · 111 participants | Moderate |
Part-time clear plastic (removable) retainer vs Any type of 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 | MD -0.34 [-0.66, -0.02] | 1 study · 59 participants | Very low |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Patient satisfaction: aesthetics (VAS 0-10 cm, 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 | MD 1.49 [0.76, 2.22] | 1 study · 32 participants | Very low |
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 |
Chlorhexidine mouthwash vs Placebo Cariogenic bacteria (Mutans streptococci) · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of MS was significantly reduced compared to placebos according to three studies [34; 48; 52]; colony count of MS was slightly reduced compared to placebo in a short time in one study [40]. | 4 studies | Very low |
Malocclusion vs No malocclusion Impaired OHRQoL measured with CPQ 11-14 (quantitative synthesis / meta-analysis) · Adolescents aged 10-19 years Malocclusions and quality of life among adolescents: a systematic review and meta-analysis. (2023) | Rate/prevalence ratio (RR/PR) 1.15 [1.12, 1.18] | 4 studies · 3672 participants | Moderate |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Plaque accumulation (Plaque Index) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · 6 months, Follow-up: 6 months White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | SMD -2.04 [-3.37, -0.70] | 5 studies · 253 participants | Ungraded |
Chlorhexidine mouthwash vs Blank control Cariogenic bacteria (Mutans streptococci) · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of MS was significantly reduced compared to blank control according to one study [53]; one study reported a significant reduction compared to baseline [51]. | 2 studies | Very low |
Part-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Stability: Little's Irregularity 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 | MD 0.92 [0.23, 1.61] | 1 study · 56 participants | Very low |
Upper clear plastic retainer + lower fixed canine-to-canine retainer vs Upper clear plastic retainer + lower interproximal reduction (adjunctive), no lower retainer Stability: Little's Irregularity Index (lower arch) · People who had received fixed appliance orthodontic treatment · 2 years, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | MD -0.30 [-0.73, 0.13] | 1 study · 47 participants | Ungraded |
Herbal mouthwash vs Placebo Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PI was significantly reduced compared to placebo [56]; VPI was significantly reduced compared to placebo [41]; PI was insignificantly reduced compared to placebo [19]. | 3 studies | Low |
Fluoride mouthwash vs Blank control Cariogenic bacteria (Mutans streptococci) · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of MS was significantly reduced compared to baseline according to two studies [33; 34]. | 2 studies | Very low |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Placebo mouthwash Pocket probing depth (PD) · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · <=3 months (short-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PD was significantly reduced except mid-lingual site compared to placebo [32]. The changes of PD were significantly higher compared to placebo [56]. | 2 studies | Low |
Clear aligners (CA) vs Conventional fixed orthodontic appliances (CF) Incidence of white spot lesions (WSLs) · Orthodontic patients undergoing comprehensive treatment (late mixed or permanent dentition, no active caries) · End of orthodontic treatment (varying) White spot lesions, plaque accumulation and salivary caries-associated bacteria in clear aligners compared… (2023) | Not meta-analyzed (heterogeneous methods; tooth-based vs patient-based incidence). 4 studies assessed WSL incidence; 3 (Albhaisi 2020 [12]; Buschang 2019 [29]; Dallel 2020 [30]) reported a lower risk of developing WSLs… | 4 studies | Ungraded |
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 |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Patient perception of pain and discomfort (VAS 0 to 100 mm) · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment · First visit Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD -0.80 [-2.20, 0.62] | 1 study · 39 participants | Very low |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Change in angulation of teeth adjacent to the space (molar and canine tipping/rotation) · 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 | Siriphan 2019 (lateral cephalometric radiographs): rate of molar movement and tipping, and canine rotation and tipping were not significantly different between groups (P>0.05). | 1 study | Ungraded |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Rate of orthodontic tooth movement during space closure stage (maxillary arch), mm/month · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment · Space closure stage Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD 0.18 [0.10, 0.26] | 1 study · 45 participants | Very low |
Full-time wear of clear plastic (thermoplastic) removable retainer vs Part-time wear of clear plastic (thermoplastic) removable retainer Stability: Little's Irregularity Index · 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 estimate extracted | 3 studies | Ungraded |