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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.

Limit to evidence status or GRADE (optional)

15,213 questions in 2,394 reviews

current versions
No studies 15,213 · 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.

QuestionEffectEvidenceStatus / GRADE
Topical local anaesthetic (spray or dental swab) vs Placebo or no treatment
Postoperative anxiety · Children and young people aged 17 years or younger having dental treatment (including extractions) under general…
Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane
None of the studies reported on postoperative anxiety0 studiesNo studies
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy
Patient satisfaction · Patients of any age in any setting requiring intervention for iatrogenic injury to the inferior alveolar or lingual…
Interventions for iatrogenic inferior alveolar and lingual nerve injury (2014) · Cochrane
Results: no included study reported quality of life or patient satisfaction. In PUB2 patient satisfaction is merged with quality of life as 'quality of life/patient satisfaction'.0 studiesNo studies
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment
Side effects / tolerability · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of…
Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane
Outcome proposed in the review but not found in any included study. The review states: 'The other outcomes proposed in this review were not found: stability of anterior open bite correction; reduction of snoring; signs…0 studiesNo studies
Dual mini-screw implant vs Single mini-screw implant
Adverse effects · Patients undergoing orthodontic treatment requiring surgical (mini-screw implant) anchorage
Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane
Adverse effects were not reported in any of the studies comparing two types of surgical anchorage0 studiesNo studies
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.)
Economic factors · Patients of any age undergoing orthodontic treatment with fixed appliances and requiring anchorage (adolescents to…
Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane
No studies reported on economic evaluation0 studiesNo studies
Powered toothbrush (any mode of action) vs Manual toothbrush
Cost (relative cost of powered vs manual) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing…
Powered versus manual toothbrushing for oral health (2014) · Cochrane
None of the included trials reported on the relative costs of manual compared with powered toothbrushes.0 studiesNo studies
Repair of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) vs Replacement of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite)
Patient satisfaction (measured by patient satisfaction or aesthetic scales) · Adults (16 years or over) with one or more defective resin composite restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above)
Replacement versus repair of defective restorations in adults: resin composite (2014) · Cochrane
No randomised controlled trials were found0 studiesNo studies
Intraligamental injection local anaesthetic vs No treatment
Participant satisfaction · Children and young people aged 17 years or younger having dental treatment (including extractions) under general…
Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane
The studies did not report on patient or child satisfaction0 studiesNo studies
Zygomatic implants without bone grafts (as a complete alternative to any bone augmentation procedure) vs Conventional dental implants in augmented maxillae
Patient satisfaction (and, when possible, preference) · Participants with an atrophic maxilla who cannot be rehabilitated with conventional dental implants due to lack of… · At least 1 year in function
Interventions for replacing missing teeth: dental implants in zygomatic bone for the rehabilitation of the… (2013) · Cochrane
Results (Effects of interventions): we could not identify any eligible randomised controlled trials (RCTs).0 studiesNo studies
Self etching primers (one-step etchant and primer system) vs Conventional etchants (two-step etch and prime method using 37% phosphoric acid)
Cost of treatment · Children and adults with fixed orthodontic brackets bonded to incisors, canines and premolars
Enamel etching for bonding fixed orthodontic braces (2013) · Cochrane
Cost of treatment: No studies assessed this outcome.NRNo studies
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment)
Non-compliance rate of the intervention · 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
Non-compliance rate was not reported in the studies of this comparison.0 studiesNo studies
Self etching primers (one-step etchant and primer system) vs Conventional etchants (two-step etch and prime method using 37% phosphoric acid)
Damage to the teeth · Children and adults with fixed orthodontic brackets bonded to incisors, canines and premolars
Enamel etching for bonding fixed orthodontic braces (2013) · Cochrane
Damage to the teeth: No studies assessed this outcome.NRNo 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
Treatment time · 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 studiesNo 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
Cost-benefit consideration · 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 studiesNo 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
Patient discomfort · 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 studiesNo studies
Intraoral distalising appliance vs Another (different) intraoral distalising 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 studiesNo studies
Stepwise excavation (two-stage caries removal, re-entry after an interval) vs One stage complete caries removal
Progression of caries · Patients with carious teeth, affecting any tooth surface(s), in unrestored primary and permanent teeth
Operative caries management in adults and children (2013) · Cochrane
None of the eight included studies reported on the primary outcome of progression of caries.0 studiesNo 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
Stability of the correction · 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 studiesNo studies
Zygomatic implants with bone grafts (as a partial alternative to bone augmentation; some augmentation still required in the frontal maxilla) vs Conventional dental implants in augmented maxillae
Outcome NR · Patients with a severely atrophic maxilla for whom some bone augmentation is still required in the frontal portion of… · At least 1 year in function
Interventions for replacing missing teeth: dental implants in zygomatic bone for the rehabilitation of the… (2013) · Cochrane
Results (Effects of interventions): we could not identify any eligible randomised controlled trials (RCTs).0 studiesNo studies
Zygomatic implants without bone grafts (as a complete alternative to any bone augmentation procedure) vs Conventional dental implants in augmented maxillae
Complications · Participants with an atrophic maxilla who cannot be rehabilitated with conventional dental implants due to lack of… · At least 1 year in function
Interventions for replacing missing teeth: dental implants in zygomatic bone for the rehabilitation of the… (2013) · Cochrane
Results (Effects of interventions): we could not identify any eligible randomised controlled trials (RCTs).0 studiesNo studies
Triclosan/copolymer-containing fluoride toothpaste vs Fluoride toothpaste without triclosan
Participant-centred outcomes (quality of life; satisfaction with product) · Children and adults (aged 16 years or less = children, over 16 = adults) without periodontitis at baseline; in…
Triclosan/copolymer containing toothpastes for oral health (2013) · Cochrane
No studies reported any participant-centred outcomes.0 studiesNo studies
Interdental brushing plus toothbrushing vs Toothbrushing alone
Bad breath (halitosis) · Dentate adults aged 16 years and older
Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane
Not estimable. No included study assessed bad breath as an outcome. (See comment)0 studiesNo studies
Pre-radiotherapy extraction of healthy molar teeth vs Conservative treatment (leaving the teeth in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)
Overall survival · Patients diagnosed with head and neck cancer planned to undergo any type of radiotherapy (external beam, intensity…
Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications (2013) · Cochrane
no estimate extracted0 studiesNo studies
Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)
Trismus preventing further restorative treatment · Patients diagnosed with head and neck cancer planned to undergo any type of radiotherapy (external beam, intensity…
Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications (2013) · Cochrane
no estimate extracted0 studiesNo studies
Acupuncture vs Placebo (sham acupuncture)
Oral health assessment · Adults with dry mouth due to radiotherapy (head and neck cancer) or Sjogren's Syndrome
Interventions for the management of dry mouth: non‐pharmacological interventions (2013) · Cochrane
no estimate extracted0 studiesNo studies
Zygomatic implants without bone grafts (as a complete alternative to any bone augmentation procedure) vs Conventional dental implants in augmented maxillae
Prosthesis failure (prosthesis could not be placed or loss of prosthesis secondary to implant failure) · Participants with an atrophic maxilla who cannot be rehabilitated with conventional dental implants due to lack of… · At least 1 year in function
Interventions for replacing missing teeth: dental implants in zygomatic bone for the rehabilitation of the… (2013) · Cochrane
Summary of findings 'Zygomatic implants versus conventional implants'; Prosthesis failure: Assumed risk (conventional) Low risk population 10 per 1000, High risk population 100 per 1000; Corresponding risk (zygomatic)…0 studiesNo studies
Resin composite restorations (filling and bonding systems) containing antibacterial agents vs Composite restorations not containing antibacterial agents
Secondary caries · Adults and adolescents in any age group with restorations in the permanent dentition and children with restorations in…
Antibacterial agents in composite restorations for the prevention of dental caries (2013) · Cochrane
No studies were included in this review, as we were unable to find any trials directly comparing antibacterial containing composites to other active interventions or controls.0 studiesNo studies
Acupuncture vs Placebo (sham acupuncture)
Duration of effectiveness · Adults with dry mouth due to radiotherapy (head and neck cancer) or Sjogren's Syndrome
Interventions for the management of dry mouth: non‐pharmacological interventions (2013) · Cochrane
no estimate extracted0 studiesNo studies
Resin composite restorations (filling and bonding systems) containing antibacterial agents vs Composite restorations not containing antibacterial agents
Costs (direct costs of interventions) · Adults and adolescents in any age group with restorations in the permanent dentition and children with restorations in…
Antibacterial agents in composite restorations for the prevention of dental caries (2013) · Cochrane
No studies were included in this review, as we were unable to find any trials directly comparing antibacterial containing composites to other active interventions or controls.0 studiesNo studies
Electrostimulation (device) vs Placebo (sham/placebo device)
Oral health assessment · Adults with dry mouth due to Sjogren's Syndrome
Interventions for the management of dry mouth: non‐pharmacological interventions (2013) · Cochrane
no estimate extracted0 studiesNo studies
A permanent restorative material or technique (e.g. amalgam; glass ionomer (type I-IV); composite resin (macrofilled, microfilled, hybrid, nanofilled); resin-modified glass ionomer (compomer, giomer); cement/cermet; stainless steel or nickel-chrome crown; pre-fabricated resin/porcelain veneer facing; microabrasion) vs A different permanent restorative material or technique
Outcome NR · Children and adolescents under 18 years with amelogenesis imperfecta requiring restorative care of anterior teeth,…
Interventions for the restorative care of amelogenesis imperfecta in children and adolescents (2013) · Cochrane
Main results: No studies met the inclusion criteria for this review. Effects of interventions: No studies met the inclusion criteria.0 studiesNo studies
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment)
Duration of 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
Duration of treatment was not reported in the studies of the appliance-versus-untreated-control comparison ("Duration of treatment, non-compliance, number of attendances required to complete treatment and adverse…0 studiesNo studies
Pre-radiotherapy extraction of healthy molar teeth vs Conservative treatment (leaving the teeth in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)
Trismus preventing further restorative treatment · Patients diagnosed with head and neck cancer planned to undergo any type of radiotherapy (external beam, intensity…
Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications (2013) · Cochrane
no estimate extracted0 studiesNo studies
Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)
Development of post-radiotherapy dental complications (caries, fractured teeth, periapical infection, periodontal disease, osteoradionecrosis) · Patients diagnosed with head and neck cancer planned to undergo any type of radiotherapy (external beam, intensity…
Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications (2013) · Cochrane
no estimate extracted0 studiesNo studies
Open (surgical) reduction and fixation vs Closed (non-surgical) treatment
Outcome NR · Adults (16 to 68 years) with mandibular fractures excluding condylar involvement
Interventions for the management of mandibular fractures (2013) · Cochrane
"There were no studies comparing different types of closed interventions with one another or comparing open and closed interventions." "We found no studies that compared surgical with non-surgical treatments."0 studiesNo studies
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing
Interproximal caries · Dentate adults aged 16 years and older
Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane
Not estimable. No included study assessed caries as an outcome. (See comment)0 studiesNo studies
Visual screening (oral visual inspection) by trained health workers vs No screening
Harms of screening (false-positive/false-negative outcomes) · Apparently healthy adults aged 35 years or older (general population), living in 13 clusters in rural areas of… · 15-year follow-up
Screening programmes for the early detection and prevention of oral cancer (2013) · Cochrane
No harms were reported.0 studiesNo studies
Electrostimulation (device) vs Placebo (sham/placebo device)
Quality of life · Adults with dry mouth due to Sjogren's Syndrome
Interventions for the management of dry mouth: non‐pharmacological interventions (2013) · Cochrane
no estimate extracted0 studiesNo studies
Progressive loading vs Direct loading
Outcome NR · Patients who are having osseointegrated root-form dental implants · 1 year
Interventions for replacing missing teeth: different times for loading dental implants (2013) · Cochrane
Progressive loading (direct vs progressive): no trial could be included; we did not identify any trials which evaluated progressive loading of implants.0 studiesNo studies
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing
Bad breath (halitosis) · Dentate adults aged 16 years and older
Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane
Not estimable. No included study assessed bad breath as an outcome. (See comment)0 studiesNo studies
Resin composite restorations (filling and bonding systems) containing antibacterial agents vs Composite restorations not containing antibacterial agents
Patient's view and satisfaction with the treatment · Adults and adolescents in any age group with restorations in the permanent dentition and children with restorations in…
Antibacterial agents in composite restorations for the prevention of dental caries (2013) · Cochrane
No studies were included in this review, as we were unable to find any trials directly comparing antibacterial containing composites to other active interventions or controls.0 studiesNo studies
A permanent restorative material or technique (e.g. amalgam; glass ionomer (type I-IV); composite resin (macrofilled, microfilled, hybrid, nanofilled); resin-modified glass ionomer (compomer, giomer); cement/cermet; stainless steel or nickel-chrome crown; pre-fabricated resin/porcelain veneer facing; microabrasion) vs A different permanent restorative material or technique
Outcome NR · Children and adolescents under 18 years with amelogenesis imperfecta requiring restorative care of posterior teeth,…
Interventions for the restorative care of amelogenesis imperfecta in children and adolescents (2013) · Cochrane
Main results: No studies met the inclusion criteria for this review. Effects of interventions: No studies met the inclusion criteria.0 studiesNo studies
Interdental brushing plus toothbrushing vs Toothbrushing alone
Quality of life · Dentate adults aged 16 years and older
Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults (2013) · Cochrane
Not estimable. No included study assessed quality of life as an outcome. (See comment)0 studiesNo studies
Resin composite restorations (filling and bonding systems) containing antibacterial agents vs Composite restorations not containing antibacterial agents
Adverse effects · Adults and adolescents in any age group with restorations in the permanent dentition and children with restorations in…
Antibacterial agents in composite restorations for the prevention of dental caries (2013) · Cochrane
No studies were included in this review, as we were unable to find any trials directly comparing antibacterial containing composites to other active interventions or controls.0 studiesNo studies
Orthodontic distalising appliance (intraoral or extraoral) vs Untreated control (no treatment)
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 in the studies of this comparison (not reported by any included study across the review).0 studiesNo studies
Intraoral distalising appliance vs Headgear (extraoral appliance)
Non-compliance rate of the intervention · 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
Non-compliance rate not reported ("The remaining secondary outcomes and adverse effects were not reported by these studies").0 studiesNo 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
Quality of life · 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 studiesNo studies
Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)
Delay in start of radiation treatment · Patients diagnosed with head and neck cancer planned to undergo any type of radiotherapy (external beam, intensity…
Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications (2013) · Cochrane
no estimate extracted0 studiesNo studies
Intraoral distalising appliance vs Headgear (extraoral appliance)
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 by these studies.0 studiesNo studies
Visual screening (oral visual inspection) by trained health workers vs No screening
Quality of life · Apparently healthy adults aged 35 years or older (general population), living in 13 clusters in rural areas of… · 15-year follow-up
Screening programmes for the early detection and prevention of oral cancer (2013) · Cochrane
Data on quality of life were not reported.0 studiesNo studies