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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.

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321 questions in 77 reviews · Dental caries

current versions
No studies 321 · 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
Preformed metal crown (fitted using the Hall Technique) vs Preformed metal crown (fitted using a conventional technique)
Outcome NR · Children with decayed primary molar teeth
Preformed crowns for decayed primary molar teeth (2015) · Cochrane
None of the included studies compared the effectiveness or safety of the Hall Technique versus the conventional technique of fitting a crown. No RCT evidence found.0 studiesNo studies
Chlorhexidine varnish vs Placebo or no treatment
Pain, quality of life, patient satisfaction or costs · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with…
Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane
No trials reported on pain, quality of life, patient satisfaction or costs.0 studiesNo studies
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment
Caries increment on primary (deciduous) whole teeth (d(m)ft), prevented fraction · Children with primary (deciduous) teeth (mostly preschool children aged under 6 years) · Nearest to 3 years
Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane
There were no data on d(m)ft available.0 studiesNo studies
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water
Disparities in caries across socioeconomic status (SES) · People of all ages in a previously fluoridated community (Maupome 2001: children with generally low caries experience)
Water fluoridation for the prevention of dental caries (2015) · Cochrane
No evidence to determine the effect of the cessation of water fluoridation on disparities in caries across SES.0 studiesNo studies
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water
Adverse effects · People of all ages in a previously fluoridated community (Maupome 2001: children with generally low caries experience)
Water fluoridation for the prevention of dental caries (2015) · Cochrane
No evidence to determine whether cessation of a water fluoridation programme is associated with any harms.0 studiesNo studies
Xylitol chewing gum vs No treatment or non-cariogenic control
Outcome NR · Children and adults · At least 1 year
Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane
It was surprising that there were no eligible randomised trials testing xylitol chewing gums against either no treatment or a non-cariogenic control.0 studiesNo studies
Chlorhexidine chewing gum vs Placebo or no intervention (including routine care)
Outcome NR · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with…
Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane
There were no trials on other products containing chlorhexidine such as sprays, toothpastes, chewing gums or mouthrinses.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)
Presence of clinical symptoms (pain, swelling, diagnosis of pulpitis, abscess formation) · 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
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Patient satisfaction (measured by patient satisfaction or aesthetic scales) · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 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)
Success or failure of restoration (as defined by the USPHS criteria) · 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
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)
Adverse events · 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
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Perioperative or postoperative pain or discomfort · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 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)
Further restoration required (repair, restoration, placement of crown/inlay, root filling) · 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
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Success or failure of restoration (as defined by the USPHS criteria) · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 studiesNo studies
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Extraction of tooth (due to decay) · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 studiesNo studies
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Adverse events · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 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)
Perioperative or postoperative pain or discomfort · 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
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)
Extraction of tooth (due to decay) · 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
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Presence of clinical symptoms (pain, swelling, diagnosis of pulpitis, abscess formation) · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 studiesNo studies
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam)
Further restoration required (repair, restoration, placement of crown/inlay, root filling) · Adults (16 years or over) with one or more defective amalgam 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: amalgam (2014) · Cochrane
No randomised controlled trials were found0 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
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
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
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
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
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
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
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
Primary school-based behavioural intervention (both oral hygiene and dietary components) vs No intervention or delayed intervention (non-intervention control; one trial's control received dental treatment plus an annual supervised toothbrushing session)
Behavioural outcomes (reported and/or other measures, e.g. data tracking toothbrushes and collecting food wrappers) · Children aged 4 to 12 years attending primary school
Primary school‐based behavioural interventions for preventing caries (2013) · Cochrane
No other behavioural outcomes (e.g. objective toothbrush tracking or food-wrapper collection) were measured by the four included studies.0 studiesNo studies
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing
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
Primary school-based behavioural intervention (both oral hygiene and dietary components) vs No intervention or delayed intervention (non-intervention control; one trial's control received dental treatment plus an annual supervised toothbrushing session)
Adverse events · Children aged 4 to 12 years attending primary school
Primary school‐based behavioural interventions for preventing caries (2013) · Cochrane
No study reported any adverse events.0 studiesNo studies
Interdental brushing plus toothbrushing vs Toothbrushing alone
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
Resin composite restorations (filling and bonding systems) containing antibacterial agents vs Composite restorations not containing antibacterial agents
Postoperative sensitivity, marginal adaptation, anatomic form and other clinical outcomes (USPHS restoration quality; includes tooth vitality and pulpitis) · 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
Interdental brushing plus toothbrushing vs Toothbrushing alone
Periodontitis (clinical attachment loss) · 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 periodontitis 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
Longevity of restorations (time to failure in months) · 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
Interdental brushing plus toothbrushing vs Flossing plus toothbrushing
Periodontitis (clinical attachment loss) · 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 clinical attachment loss, a measure of progression of periodontitis. (See comment)0 studiesNo studies
Fluoride supplements (tablets, drops, lozenges or chewing gums) vs Topical fluoride (fluoride rinse, varnish or toothpaste)
Fluorosis (adverse effect; % of children with fluorotic teeth) · Children and adolescents (aged 16 years or less at baseline)
Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing dental caries in children (2011) · Cochrane
Summary of findings 2 lists fluorosis (% of children with fluorotic teeth) as 'See comment / Not estimable / Not estimated'; no included study reported fluorosis for the fluoride supplements versus topical fluoride…NRNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Economic and resource cost of flossing · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not reported. No included study measured the economic or resource cost of flossing; the review notes it may be important to measure in future trials.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Interproximal caries · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). See comment: No included study assessed caries as an outcome.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Clinical attachment loss · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). SoF comment reads (verbatim) 'No included study assessed calculus as an outcome' (apparent copy-paste typo in the clinical attachment loss row; no study assessed clinical attachment loss).0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Bad breath (halitosis) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not reported. No included study measured halitosis; the review notes it may be important to measure in future trials.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Calculus · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). See comment: No included study assessed calculus as an outcome.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Quality of life · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). See comment: No included study assessed quality of life as an outcome.0 studiesNo studies
Intensity modulated radiotherapy (IMRT) vs Conventional or other radiotherapy
Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and…
Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane
Discussion: 'There are currently no trials of IMRT in this systematic review' (the PARSPORT trial was underway, expected 2013). No eligible trials of intensity modulated radiotherapy identified.0 studiesNo studies
Altered fractionation radiotherapy plus chemotherapy vs Chemoradiotherapy with standard (conventional) fractionation
Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and…
Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane
Discussion: 'there are no completed trials of altered fractionation plus chemotherapy versus chemoradiotherapy with standard fractionation.'0 studiesNo studies
Altered fractionation radiotherapy vs Chemoradiotherapy (concurrent, standard fractionation)
Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and…
Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane
Discussion: altered fractionation radiotherapy 'has not been directly compared to chemoradiotherapy'. No eligible head-to-head trials.0 studiesNo studies