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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 |
|---|---|---|---|
Intraoral distalising appliance vs Headgear (extraoral appliance) Number of attendances required to complete treatment · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | Number of attendances required to complete treatment was not reported by these studies. | 0 studies | No studies |
Root canal medicaments vs No medicaments, placebo, or a different type of medicament Outcome NR · Patients (mainly children and young adults) with a history of dental trauma and a diagnosis of luxation (intrusion,… · Minimum 12 months follow-up Interventions for treating traumatised permanent front teeth: luxated (dislodged) teeth (2013) · Cochrane | Types of root canal medicaments: this was compared with no medicaments, placebo and different types of medicaments. Main results: No randomised or quasi-randomised controlled trials were found; no study was included in… | 0 studies | No studies |
Intraoral distalising appliance vs Another (different) intraoral distalising appliance Movement of upper incisor teeth (mm) · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | SoF table 3. Assumed risk "Not estimated"; Corresponding risk "Not estimated"; Relative effect "Meta-analysis not appropriate". Quality: very low. Comment: "No pooled estimate due to different types of appliances used… | 2 studies · 70 participants | Very low |
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment) Adverse effects (headgear injuries, gum health, tooth damage/decay, root resorption) · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | Adverse effects were not reported in the studies of this comparison; no included study across the review reported adverse effects, harm or injury. | 0 studies | No studies |
Intraoral distalising appliance vs Another (different) intraoral distalising appliance Change in overjet (mm) · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | SoF table 3. Assumed risk "Not estimated"; Corresponding risk "Not estimated"; Relative effect "Meta-analysis not appropriate". Quality: very low. Comment: "No pooled estimate due to different types of appliances used… | 2 studies · 70 participants | Very low |
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment) Movement of upper first molars (mm) · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | SoF table 1 (orthodontic appliance vs untreated control). Illustrative comparative risks: Assumed risk (untreated control) "Not estimated"; Corresponding risk (orthodontic appliance) "Not estimated"; Relative effect… | 2 studies · 74 participants | Low |
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment) Change in overjet (mm) · Children and adolescents (aged 16 years or less at the start of treatment) undergoing orthodontic treatment to… Orthodontic treatment for distalising upper first molars in children and adolescents (2013) · Cochrane | SoF table 1. Assumed risk "Not estimated"; Corresponding risk "Not estimated"; Relative effect "Meta-analysis not appropriate". Comment: "No pooled estimate due to different types of appliances (First Class and… | 2 studies · 74 participants | Low |
Fixation (splinting) vs No splint, or a different type or duration of splint Outcome NR · Patients (mainly children and young adults) with a history of dental trauma and a diagnosis of luxation (intrusion,… · Minimum 12 months follow-up Interventions for treating traumatised permanent front teeth: luxated (dislodged) teeth (2013) · Cochrane | Types and duration of fixation: the effect of using no splint or different types of splints and their duration. Main results: No randomised or quasi-randomised controlled trials were found; no study was included in… | 0 studies | No studies |
Any intervention to manage relapse: fixed options (labial braces, lingual braces, fixed lingual wire) or removable options (Hawley's retainer with spring elastomeric module, Bloore removable aligner, other Hawley's retainer modifications, Invisalign, Clearstep) vs Another such intervention or no active treatment; all interventions compared against each other in any combination Assessment of the alignment of the lower front teeth using any method or index · Participants who previously underwent orthodontic treatment, with subsequent crowding (relapse) of the lower front… Interventions for managing relapse of the lower front teeth after orthodontic treatment (2013) · Cochrane | No RCTs met the inclusion criteria for this review. After deduplication, the electronic searching identified 527 publications; after reviewing the titles and abstracts, none focused on interventions to correct the… | 0 studies | No studies |
Self etching primers (one-step etchant and primer system) vs Conventional etchants (two-step etch and prime method using 37% phosphoric acid) Decay (decalcification) associated with or around the etching field · Children and adults with fixed orthodontic brackets bonded to incisors, canines and premolars Enamel etching for bonding fixed orthodontic braces (2013) · Cochrane | Decay (decalcification) associated with or around the etching field: Only one study (Ghiz 2009) assessed this outcome but data were reported at the tooth level rather than at the participant level and therefore was not… | 1 study · 25 participants | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Time to eruption of the permanent canine · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Time to eruption of the permanent canine was reported by both trials. The paper reports there was 'no significant difference between the two interceptive approaches in the time required for canine eruption' (extraction… | 2 studies | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Patient satisfaction and pain experience during extraction of the primary canine · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Neither trial reported the outcome of pain, or patient satisfaction. | 0 studies | No studies |
Vertical ramus osteotomy (VRO) with osteosynthesis vs Vertical ramus osteotomy (VRO) without osteosynthesis Changes in condyle position: fossa-condyle relations for anterior (1 year post-operative) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD 0.00 [-0.38, 0.38] | 1 study · 53 participants | Ungraded |
Extraction of the primary maxillary canine plus cervical pull headgear vs Untreated control (no treatment) Prevalence of eruption/non-eruption of the palatally displaced permanent canine (successful eruption) · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Narrative (not pooled, not GRADE-rated). Leonardi 2004: successful eruption 80% with extraction plus cervical pull headgear, significantly higher than the untreated control group (Chi2 14.9; P<0.01). Baccetti 2008: the… | 2 studies · 81 participants | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Incidence or prevalence of root resorption of the impacted canine and/or incisors and cyst formation · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Root resorption of the impacted canine and/or incisors and cyst formation was not reported by either included trial. | 0 studies | No studies |
Vertical ramus osteotomy (VRO) with osteosynthesis vs Vertical ramus osteotomy (VRO) without osteosynthesis Changes in condyle position: fossa-condyle relations for posterior (1 year post-operative) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD -0.10 [-0.64, 0.44] | 1 study · 53 participants | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Improvement in the vertical position or angulation of the ectopic canine, measured from radiographs (inclination to midline, cusp-tip to occlusal line, medial crown position) · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Changes in the position of the displaced canine measured from radiographs, reported by both trials as medians (non-normal distribution): changes in the inclination of the canine to the midline, the distance of the… | 2 studies | Ungraded |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: vertical changes of pogonion (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD 0.41 [-0.15, 0.97] | 1 study · 30 participants | Ungraded |
Any orthodontic and/or surgical treatment for Angle Class III malocclusion vs No intervention or another treatment technique Correction of prominent lower front teeth / effectiveness of treatment (planned primary outcome) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… Treatments for adults with prominent lower front teeth (2012) · Cochrane | No included study measured the planned primary outcome. Discussion: 'The primary outcome proposed for this review was to evaluate the effectiveness of treatments for prognathism, but none of the studies conclusively… | NR | No studies |
Extraction of the primary maxillary canine plus cervical pull headgear vs Extraction of the primary maxillary canine alone Prevalence of eruption/non-eruption of the palatally displaced permanent canine (successful eruption) · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Narrative (not pooled, not GRADE-rated). Leonardi 2004: extraction plus headgear (80%) gave significantly higher eruption than extraction alone (50%) (Chi2 4.69; P<0.05). Baccetti 2008: extraction plus headgear was… | 2 studies · 79 participants | Ungraded |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: sagittal changes of B-point (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD -0.22 [-0.58, 0.14] | 1 study · 30 participants | Ungraded |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: sagittal changes of pogonion (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD -0.24 [-0.67, 0.19] | 1 study · 30 participants | Ungraded |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: vertical changes of B-point (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD 0.09 [-0.44, 0.62] | 1 study · 30 participants | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Change in the sagittal position of the upper first molars · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Change in the sagittal position of the upper first molars (Baccetti 2008 only): average sagittal displacement was 2.65 mm in the extraction-only group and 2.32 mm in the untreated control group (0.24 mm in the… | 1 study | Ungraded |
Extraction of the primary maxillary canine vs Untreated control (no treatment) Prevalence of eruption/non-eruption of the palatally displaced permanent canine (successful eruption) · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane | Narrative summary (data not poolable, not GRADE-rated). Leonardi 2004: successful eruption of the permanent canine 50% in the extraction-only group, which was not significantly greater than the success rate in… | 2 studies · 70 participants | Ungraded |
Orthodontic treatment with appliances inducing stable, permanent orthodontic tooth movement (splints worn 8 to 12 weeks and surgical interventions excluded) vs Control: no treatment, placebo, or reassurance Patient quality of life · Adults aged 18 years or older with clinically diagnosed TMD (exhibiting two or more of the listed signs and/or symptoms) · At least 6 months after the intervention Orthodontics for treating temporomandibular joint (TMJ) disorders (2010) · Cochrane | no estimate extracted | 0 studies | No studies |
Orthodontic treatment with appliances inducing stable, permanent orthodontic tooth movement (splints worn 8 to 12 weeks and surgical interventions excluded) vs Control: no treatment, placebo, or reassurance Adverse effects on oral health · Adults aged 18 years or older with clinically diagnosed TMD (exhibiting two or more of the listed signs and/or symptoms) · At least 6 months after the intervention Orthodontics for treating temporomandibular joint (TMJ) disorders (2010) · Cochrane | no estimate extracted | 0 studies | No studies |
Orthodontic treatment with appliances inducing stable, permanent orthodontic tooth movement (splints worn 8 to 12 weeks and surgical interventions excluded) vs Control: no treatment, placebo, or reassurance Limitation of movement · Adults aged 18 years or older with clinically diagnosed TMD (exhibiting two or more of the listed signs and/or symptoms) · At least 6 months after the intervention Orthodontics for treating temporomandibular joint (TMJ) disorders (2010) · Cochrane | no estimate extracted | 0 studies | No studies |
Orthodontic treatment with appliances inducing stable, permanent orthodontic tooth movement (splints worn 8 to 12 weeks and surgical interventions excluded) vs Control: no treatment, placebo, or reassurance Development of TMD (onset/incidence of signs and symptoms) · People without TMD at baseline undergoing orthodontic treatment (TMD clinically absent at baseline); no age… · Follow-up period extended into adulthood Orthodontics for treating temporomandibular joint (TMJ) disorders (2010) · Cochrane | no estimate extracted | 0 studies | No studies |
Orthodontic treatment with appliances inducing stable, permanent orthodontic tooth movement (splints worn 8 to 12 weeks and surgical interventions excluded) vs Control: no treatment, placebo, or reassurance Overall symptoms, pain and headache (relief from symptoms assessed by global measures) · Adults aged 18 years or older with clinically diagnosed TMD (exhibiting two or more of the listed signs and/or symptoms) · At least 6 months after the intervention Orthodontics for treating temporomandibular joint (TMJ) disorders (2010) · Cochrane | no estimate extracted | 0 studies | No studies |