Gap finder
Search review questions
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 |
|---|---|---|---|
Chemical cured composite vs Conventional (chemical cured) glass ionomer cement Bracket (bond) failure · Patients with fixed orthodontic appliances attached to their teeth · To end of appliance treatment Adhesives for fixed orthodontic brackets (2018) · Cochrane | The one trial article for this adhesive comparison reported the results of paired t-tests comparing different sides of the mouth. No standard deviations were presented, so we were unable to reproduce the data. The… | 1 study · 60 participants | Ungraded |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance Final ANB · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.89 [-1.38, -0.4] | 3 studies · 419 participants | Ungraded |
Orthodontic treatment without extraction of permanent teeth (removable, fixed, or functional braces, or headgear) vs No treatment (or delayed treatment) Participant discomfort · Children (80% aged <= 16 years) with a Class II division 2 malocclusion (deep bite and retroclined upper front teeth) Orthodontic treatment for deep bite and retroclined upper front teeth in children (2018) · Cochrane | no estimate extracted | 0 studies | No studies |
Late treatment (one-phase) with removable functional appliance vs No treatment Incidence of incisal trauma · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | Incidence of incisal trauma: Not measured | NR | No studies |
Removable functional appliance vs Fixed functional appliance Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.74 [0.15, 1.33] | 2 studies · 154 participants | Low |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance Final overjet · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.21 [-0.1, 0.51] | 3 studies · 343 participants | Low |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance Incidence of incisal trauma · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | OR 0.72 [0.35, 1.49] | 2 studies · 281 participants | Ungraded |
Orthodontic treatment without extraction of permanent teeth (removable, fixed, or functional braces, or headgear) vs No treatment (or delayed treatment) Quality of life · Children (80% aged <= 16 years) with a Class II division 2 malocclusion (deep bite and retroclined upper front teeth) Orthodontic treatment for deep bite and retroclined upper front teeth in children (2018) · Cochrane | no estimate extracted | 0 studies | No studies |
Early treatment (two-phase) with headgear vs Early treatment (two-phase) with functional appliance PAR score · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.81 [-2.21, 0.58] | 2 studies · 224 participants | Ungraded |
Early treatment (two-phase) with headgear vs Late treatment (one-phase in adolescence) with headgear Final overjet · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.22 [-0.56, 0.12] | 2 studies · 238 participants | Low |
Chemical cured composite vs Compomer (polyacid-modified resin composite) Decalcification · Patients with fixed orthodontic appliances attached to their teeth · To end of appliance treatment Adhesives for fixed orthodontic brackets (2018) · Cochrane | However the paper reported that the compomer offered better protection against decalcification when compared by a sign test (P = 0.0075) (Millett 2000). No effect estimate or confidence interval was reported. | 1 study · 45 participants | Ungraded |
Twin Block functional appliance (conventional) vs Modified Twin Block appliances Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.23 [-0.67, 0.22] | 2 studies · 196 participants | Ungraded |
Late treatment (one-phase) with fixed functional appliance vs No treatment Incidence of incisal trauma · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | Incidence of incisal trauma: Not measured | NR | No studies |
Fixed functional appliance (FORSUS FRD) vs Intermaxillary elastics Final ANB · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.9 [-1.96, 0.16] | 1 study · 28 participants | Ungraded |
Fixed functional appliance (FORSUS FRD) vs Intermaxillary elastics Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.28 [-0.35, 0.91] | 1 study · 28 participants | Ungraded |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance Self concept · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -3.63 [-7.66, 0.4] | 1 study · 135 participants | Ungraded |
Early treatment (two-phase) with headgear vs Early treatment (two-phase) with functional appliance Final overjet · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.21 [-0.57, 0.15] | 2 studies · 225 participants | Ungraded |
Early treatment (two-phase) with headgear vs Late treatment (one-phase in adolescence) with headgear Incidence of incisal trauma · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | OR 0.76 [0.37, 1.54] | 2 studies · 285 participants | Ungraded |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance PAR score · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -10.52 [-12.32, -8.71] | 2 studies · 349 participants | Ungraded |
Early treatment (two-phase) with headgear vs Late treatment (one-phase in adolescence) with headgear Final overjet · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -1.07 [-1.63, -0.51] | 2 studies · 278 participants | Ungraded |
Removable functional appliance vs Fixed functional appliance Incidence of incisal trauma · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | Incidence of Incisal trauma: Not measured | NR | No studies |
Orthodontic treatment without extraction of permanent teeth (removable, fixed, or functional braces, or headgear) vs No treatment (or delayed treatment) Dento-occlusal results of treatment, measured with the PAR index · Children (80% aged <= 16 years) with a Class II division 2 malocclusion (deep bite and retroclined upper front teeth) Orthodontic treatment for deep bite and retroclined upper front teeth in children (2018) · Cochrane | No data are available as no RCTs or CCTs have been conducted. | 0 studies | No studies |
Activator functional appliance vs Fixed functional appliance (FORSUS FRD EZ) Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 2.19 [0.58, 3.8] | 1 study · 24 participants | Ungraded |
Early treatment (two-phase) with headgear vs Late treatment (one-phase in adolescence) with headgear Final ANB · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.72 [-1.18, -0.27] | 2 studies · 277 participants | Ungraded |
Late treatment (one-phase) with removable functional appliance vs No treatment Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -4.62 [-5.33, -3.92] | 3 studies · 122 participants | Low |
Twin Block functional appliance vs Other functional appliances (Bionator, Herbst, R-appliance, Dynamax, Bite-Jumping) Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.08 [-0.6, 0.76] | 4 studies · 259 participants | Low |
Early treatment (two-phase) with headgear vs Early treatment (two-phase) with functional appliance Final ANB · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.04 [-0.49, 0.41] | 2 studies · 271 participants | Ungraded |
Chemical cured composite vs Compomer (polyacid-modified resin composite) Bracket (bond) failure · Patients with fixed orthodontic appliances attached to their teeth · To end of appliance treatment Adhesives for fixed orthodontic brackets (2018) · Cochrane | OR 0.86 [0.24, 2.98] | 1 study · 45 participants | Ungraded |
FMA stepwise advancement (SWG) vs FMA single step advancement (SSG) Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.23 [-0.26, 0.72] | 1 study · 34 participants | Ungraded |
Early treatment (two-phase) with headgear vs Early treatment (two-phase) with functional appliance Final overjet · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of phase I (growth modification phase) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.75 [0.21, 1.29] | 2 studies · 271 participants | Ungraded |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance PAR score · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD 0.62 [-0.66, 1.91] | 3 studies · 360 participants | Ungraded |
Late treatment (one-phase) with fixed functional appliance vs No treatment Final overjet · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -5.46 [-6.63, -4.28] | 2 studies · 61 participants | Low |
FMA stepwise advancement (SWG) vs FMA single step advancement (SSG) Final ANB · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.69 [-1.19, -0.19] | 1 study · 34 participants | Ungraded |
Early treatment (two-phase: phase 1 in childhood, phase 2 in adolescence) with functional appliance vs Late treatment (one-phase in adolescence) with functional appliance Final ANB · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.02 [-0.47, 0.43] | 3 studies · 347 participants | Moderate |
Twin Block functional appliance vs Other functional appliances (Bionator, Herbst, R-appliance, Dynamax, Bite-Jumping) Incidence of incisal trauma · Adolescents (age 12 to 16 years) receiving orthodontic treatment to correct prominent upper front teeth (Class II… · End of orthodontic treatment Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | Incidence of incisal trauma: Not measured | NR | No studies |
Orthodontic treatment without extraction of permanent teeth vs Orthodontic treatment involving extraction of permanent teeth Number of visits to complete treatment · Children (80% aged <= 16 years) with a Class II division 2 malocclusion (deep bite and retroclined upper front teeth) Orthodontic treatment for deep bite and retroclined upper front teeth in children (2018) · Cochrane | no estimate extracted | 0 studies | No studies |
Early treatment (two-phase) with headgear vs Late treatment (one-phase in adolescence) with headgear Final ANB · Children (7 to 11 years) and adolescents (12 to 16 years) with prominent upper front teeth (Class II malocclusion) · End of orthodontic treatment (phase II) Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents (2018) · Cochrane | MD -0.27 [-0.8, 0.26] | 2 studies · 231 participants | Low |
Orthodontic treatment without extraction of permanent teeth vs Orthodontic treatment involving extraction of permanent teeth Participant discomfort · Children (80% aged <= 16 years) with a Class II division 2 malocclusion (deep bite and retroclined upper front teeth) Orthodontic treatment for deep bite and retroclined upper front teeth in children (2018) · Cochrane | no estimate extracted | 0 studies | No studies |
Ibuprofen taken pre-emptively (about 1 hour before treatment) vs Ibuprofen taken post-treatment Rescue analgesia · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | RR 0.8 [0.3, 1.9] | 2 studies · 41 participants | Ungraded |
Open surgical exposure vs Closed surgical exposure Gum health: midbuccal gingival recession (mm) · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · 3 months post-debond Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | MD -0.02 [-0.21, 0.16] | 2 studies · 105 participants | Ungraded |
Analgesic (any: NSAID, paracetamol, local anaesthetic or opioid) vs Control (placebo or no treatment) Pain intensity (VAS 0-100 mm) · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) · 2 hours Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | MD -11.66 [-16.15, -7.17] | 10 studies · 685 participants | Moderate |
Open surgical exposure vs Closed surgical exposure Gum health: periodontal probing depth · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · 3 months post-debond Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | MD -0.14 [-0.48, 0.20] | 1 study · 43 participants | Ungraded |
Bonded molar tubes (attached with adhesive) vs Molar bands (cemented, e.g. with glass ionomer cement) Adverse events (illness, allergy, bad taste, mucosal trauma) · Participants with full arch fixed orthodontic appliance(s) with molar tubes bonded to first or second permanent… Adhesives for bonded molar tubes during fixed brace treatment (2017) · Cochrane | No other adverse events identified | 2 studies | Ungraded |
Topical NSAID (ketoprofen lysinate mouthwash, 160 mg) vs Topical NSAID (benzidamine hydrochloride mouthwash, 22.5 mg) Time off school or work · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | The study did not report this outcome. | 0 studies | No studies |
Analgesic (any: NSAID, paracetamol, local anaesthetic or opioid) vs Control (placebo or no treatment) Quality of life or participant satisfaction · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | Reported narratively by 2 studies (Wang 2012: SF-36 and SAS - significant reduction in SF-36 bodily pain at 30 days vs baseline, no significant between-group differences; Minor 2009: STAI and PANAS - no significant… | 2 studies | Ungraded |
Ibuprofen taken pre-emptively (about 1 hour before treatment) vs Ibuprofen taken post-treatment Pain intensity (VAS 0-100 mm) · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) · 24 hours Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | MD -9.74 [-47.88, 28.40] | 2 studies · 69 participants | Very low |
Open surgical exposure vs Closed surgical exposure Complications or adverse effects · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · Perioperative to alignment Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | SoF (Complications, no GRADE rating given): 'One surgical failure was due to detachment of the gold chain (closed group). One study reported two complications following surgery, both in the closed group: a… | 1 study | Ungraded |
NSAID (systemic) vs Paracetamol Rescue analgesia · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | RR 1.5 [0.6, 3.6] | 1 study · 159 participants | Very low |
Topical NSAID (ketoprofen lysinate mouthwash, 160 mg) vs Topical NSAID (benzidamine hydrochloride mouthwash, 22.5 mg) Failure to complete orthodontic treatment due to pain · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | The study did not report this outcome. | 0 studies | No studies |
Open surgical exposure vs Closed surgical exposure Patient response: pain/soreness score (visual analogue scale 1 to 10) · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · Postoperative Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | MD 0.00 [-1.09, 1.09] | 1 study · 60 participants | Ungraded |