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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.
10,375 questions in 429 reviews · Oral Health
current versionsNo studies 1,344 · 13%Ungraded 6,832 · 65.9%Very low 1,228 · 11.8%Low 613 · 5.9%Moderate 290 · 2.8%High 68 · 0.7%
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 |
|---|---|---|---|
Chlorhexidine oral product (one formulation/concentration) vs Another chlorhexidine formulation, concentration or application frequency 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 | no estimate extracted | 0 studies | No studies |
Chlorhexidine gel (0.12%) vs No treatment Adverse events · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… · 24 months, primary dentition Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | Both studies reported there were no adverse events. | 2 studies | Ungraded |
Orthodontic appliances (palatal crib) vs No treatment Sucking cessation (long term) · Children with a non-nutritive sucking habit (digit or pacifier) · Long term (12 months or more) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | RR 5.81 [1.49, 22.66] | 1 study · 37 participants | Ungraded |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs Control (no treatment or standard/usual oral care, e.g. saline rinse) Oral mucositis (severe) · All patients with cancer who are receiving treatment · High-dose melphalan-based treatment prior to HSCT (haematological cancers) Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | RR 0.38 [0.20, 0.72] | 5 studies · 270 participants | Moderate |
Higher water fluoride concentration (fluoridated water; natural or artificial) vs Lower water fluoride concentration (concurrent control) Dental fluorosis of aesthetic concern (Dean's Index, TFI, TSIF) · Populations of all ages (mostly children) exposed to drinking water with differing fluoride concentrations · Cross-sectional Water fluoridation for the prevention of dental caries (2015) · Cochrane | OR 2.90 [2.05, 4.10] | 40 studies · 59630 participants | Low |
Repositioning of ankylosed teeth after osteotomy followed or not by distraction osteogenesis, or after luxation vs Conventional orthodontic treatment or follow-up with no specific treatment for ankylosis Outcome NR · Any patient with ankylosis and displacement of permanent front teeth diagnosed by clinical and radiographic… Interventions for treating traumatised ankylosed permanent front teeth (2015) · Cochrane | no estimate extracted | 0 studies | No studies |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs High-dose leucovorin rinse Oral mucositis (severe) · Patients with osteosarcoma (bone cancer) receiving high-dose methotrexate, vincristine and leucovorin Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Oral mucositis (severe). Not estimable - no participants had developed severe oral mucositis by the fourth day after chemotherapy when the data were reported (Zhang 2011, Analysis 4.3, subgroup 3.2); 81 participants in… | 1 study · 81 participants | Ungraded |
Xylitol sucking tablets (1 g/day) vs No treatment Number of infants with a caries increment · Infants/young children (primary teeth; baseline about 1 to 3 years) · 18 months (24-month follow-up) Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | RR 0.72 [0.35, 1.45] | 1 study · 118 participants | Ungraded |
Parasympathomimetic drugs (choline esters, cholinesterase inhibitors) vs No treatment Outcome NR · Patients with radiation-induced salivary gland dysfunction Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (2015) · Cochrane | no estimate extracted | 0 studies | No studies |
Palatal arch vs Palatal crib (alternative orthodontic appliance) Sucking cessation (short term) · Children with a non-nutritive sucking habit (digit or pacifier) · Short term (less than 12 months) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | RR 0.13 [0.03, 0.59] | 1 study · 22 participants | Very low |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Cost · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
Tyrosine kinase inhibitor (erlotinib, gefitinib or lapatinib) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Adverse effects · People with squamous cell carcinoma of the oral cavity or oropharynx · 40 to 60 months, Gastrointestinal complaints (lapatinib, all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 15.53 [2.18, 110.55] | 1 study · 67 participants | Ungraded |
Tyrosine kinase inhibitor (erlotinib, gefitinib or lapatinib) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Adverse effects · People with squamous cell carcinoma of the oral cavity or oropharynx · 40 to 60 months, Skin toxicity (erlotinib, all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 6.57 [3.60, 12.00] | 1 study · 191 participants | Ungraded |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Cost · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Adverse effects · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months, Skin toxicity/acneiform rash (cetuximab, all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 6.56 [5.35, 8.03] | 2 studies · 1311 participants | Ungraded |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs Control (no treatment or standard/usual oral care, e.g. saline rinse) Number of days of treatment with opioid analgesics · All patients with cancer who are receiving treatment · Fluorouracil (5FU) treatment for solid cancers Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | No studies in the 5FU subgroup assessed the number of days of treatment with opioid analgesics. | 0 studies | No studies |
Fixed-appliance orthodontic treatment incorporating surgically assisted orthodontics (adjunctive surgical procedure: corticotomy, micro-osteoperforation or interseptal bone reduction) to increase the rate of tooth movement vs Conventional treatment: fixed-appliance orthodontic treatment without surgical assistance Duration of orthodontic treatment, number of visits during active treatment (scheduled and unscheduled) and duration of visits · Individuals of any age receiving orthodontic treatment with fixed appliances (braces) (people requiring orthodontic… Surgical adjunctive procedures for accelerating orthodontic treatment (2015) · Cochrane | SoF row: Illustrative comparative risks '‐' / '‐'; no relative effect; Comments: 'Not reported'. Results: 'Our prespecified primary outcome (the duration of orthodontic treatment, number of visits during active… | 0 studies | No studies |
Non-specific immunotherapy (recombinant interleukin-2 or BCG cell wall preparation) plus standard therapy vs Standard therapy alone Disease-free survival · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months, Recombinant interleukin-2 + surgery (De Stefani 2002) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | HR 0.66 [0.43, 1.02] | 1 study · 201 participants | Very low |
Xylitol lozenges (5 g/day) vs Control lozenges (sucralose-sweetened placebo, no xylitol) Caries increment (DFS) · Adults · 33 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | PF 0.08 [-0.03, 0.20] | 1 study · 669 participants | Low |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Progression-free survival · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months, Monoclonal antibody + chemoradiotherapy vs chemoradiotherapy alone Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | HR 1.08 [0.89, 1.32] | 1 study · 891 participants | Ungraded |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs Control (no treatment or standard/usual oral care, e.g. saline rinse) Quality of life · All patients with cancer who are receiving treatment · High-dose melphalan-based treatment prior to HSCT (haematological cancers) Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Summary of findings 2 (melphalan/HSCT): Quality of life - '1 study assessed this outcome but the data are currently unavailable as the study report and analysis have not yet been completed' (Toro 2013; measured with… | 1 study | Ungraded |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Caries in permanent teeth (change in DMFT) · People of all ages in a community setting; the included caries studies were all in children aged 3 to 16 years · Follow-up 8 to 11 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD -1.16 [-1.61, -0.72] | 10 studies · 78764 participants | Low |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Adverse events: gingival bleeding · Children with decayed primary molar teeth · Short term (up to 12 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 1.69 [0.61, 4.66] | 2 studies · 226 participants | Ungraded |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Satisfaction with treatment · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Satisfaction with treatment: listed in the Summary of findings table with no data; the studies did not measure this outcome. | 0 studies | No studies |
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment Unacceptability of treatment (dropouts/exclusions during the trial) · Children and adolescents aged 16 years or younger · During trial Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 1.03 [0.89, 1.19] | 19 studies | Ungraded |
Endodontic therapy (surgical or non-surgical) performed with the aid of one or more magnification devices (surgical microscope, endoscope or magnifying loupes) vs The same endodontic therapy performed without magnification devices (without visual enhancers) Quality of root-end filling (retrograde/surgical treatment) · Patients of any age who received endodontic therapy and were followed up for at least 1 year after treatment Magnification devices for endodontic therapy (2015) · Cochrane | No included study assessed this outcome; the review notes that such secondary outcomes were only sporadically reported and were never statistically assessed. | NR | No studies |
Pacifier withdrawal vs No treatment Outcome NR · Children with a non-nutritive sucking habit (digit or pacifier) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | There were no studies that looked at barrier techniques or pacifier withdrawal. | 0 studies | No studies |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs Control (no treatment or standard/usual oral care, e.g. saline rinse) Adverse events · All patients with cancer who are receiving treatment · High-dose melphalan-based treatment prior to HSCT (haematological cancers) Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Adverse events reported narratively: one study did not report adverse events (Askarifar 2015); another reported no serious adverse events (Toro 2013); the remaining two reported low rates of shooting pain from the… | 3 studies | Ungraded |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Patient satisfaction and quality of life (any validated instrument) · People with a permanent tooth that has undergone endodontic (root canal) treatment Single crowns versus conventional fillings for the restoration of root‐filled teeth (2015) · Cochrane | This outcome was not reported nor measured by the study. The abstract confirms no evidence was available for any secondary outcome. | NR | No studies |
Oral cryotherapy (ice chips, ice-cold water, ice cubes or crushed ice held in the mouth during cancer treatment) vs Low-dose leucovorin rinse Oral mucositis (severe) · Patients with osteosarcoma (bone cancer) receiving high-dose methotrexate, vincristine and leucovorin Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Oral mucositis (severe). Not estimable - no participants had developed severe oral mucositis by the fourth day after chemotherapy when the data were reported (Zhang 2011, Analysis 4.3, subgroup 3.1); 118 participants… | 1 study · 118 participants | Ungraded |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Pain · Children with decayed primary molar teeth · Long term (12 months to 24 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 0.15 [0.04, 0.67] | 2 studies · 312 participants | Moderate |
Fluoridated milk vs Non-fluoridated milk Adverse effects: dental fluorosis · General population, irrespective of age or level of risk for dental caries Fluoridated milk for preventing dental caries (2015) · Cochrane | No evidence found. (Correspondence with the author (Maslak 2004) confirmed that no adverse effects were reported.) | 0 studies | No studies |
Glass ionomer sealant (with fluoride gel plus dentifrice) vs Fluoride gel plus fluoride toothpaste/dentifrice (non-invasive control) Caries (lesion) progression (radiographic) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 12 to 36 months (radiographic follow-up), Glass ionomer sealant Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.13 [0.01, 2.52] | 1 study | Ungraded |
Endodontic therapy performed with one type of magnification device (surgical microscope, endoscope or magnifying loupes) vs Endodontic therapy performed with a different type of magnification device Quality of root-end filling (retrograde/surgical treatment) · Patients of any age who received endodontic therapy and were followed up for at least 1 year after treatment Magnification devices for endodontic therapy (2015) · Cochrane | No included study assessed this outcome; the review notes that such secondary outcomes were only sporadically reported and were never statistically assessed. | NR | No studies |
Xylitol syrup (high dose, 8 g/day) vs Control (low-dose xylitol, 2.67 g/day) syrup Adverse effects (loose stools, diarrhoea) · Infants (primary teeth; baseline about 9 to 15 months) · 12 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | Adverse effects were not reported in a usable format, but the reported rates of loose stools and diarrhoea were very similar between groups. There were no serious adverse effects during the study. Milgrom 2009. | 1 study · 94 participants | Ungraded |
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water Change in proportion of caries-free children (deciduous or permanent teeth) · 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 the proportion of caries-free children. | 0 studies | No studies |
Preformed crown (any material; conventional technique or Hall Technique) vs No treatment Outcome NR · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Crown versus no treatment was a planned comparison (Comparison 2: crown versus no crown or filling). No study evaluated crown versus no treatment; the only study in this comparison (Santamaria 2014) used active… | 0 studies | No studies |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Pain · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Pain: No evidence available (Summary of findings 2). | 0 studies | No studies |
Oral cryotherapy for 30 minutes vs Oral cryotherapy for 60 minutes Oral mucositis (moderate to severe) · Adults with solid cancers receiving fluorouracil (5FU) and leucovorin Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | RR 0.68 [0.36, 1.30] | 1 study · 178 participants | Very low |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Time to restoration failure/retreatment · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
Non-specific immunotherapy (recombinant interleukin-2 or BCG cell wall preparation) plus standard therapy vs Standard therapy alone Adverse effects · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months, Nausea/vomiting (rIL-2, grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 3.40 [0.15, 77.34] | 1 study · 30 participants | Ungraded |
Chlorhexidine varnish vs Placebo or no treatment Adverse events (e.g. ulcers, tooth staining) · 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 | One study reported no adverse events for ulcers or tooth staining. One study stated "side-effects due to the CHX treatment were not noted". | 2 studies | Ungraded |
Tyrosine kinase inhibitor (erlotinib, gefitinib or lapatinib) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Progression-free survival · People with squamous cell carcinoma of the oral cavity or oropharynx · 40 to 60 months Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | HR 0.80 [0.51, 1.28] | 2 studies · 271 participants | Very low |
Xylitol candy (7.5 g/day) vs Control (sorbitol) candy Adverse effects · Children (mixed dentition; baseline about 8 years) · 36 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | The authors reported that there were no adverse effects for either group. Honkala 2014. | 1 study · 252 participants | Ungraded |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Participant satisfaction · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | No included studies addressed participant satisfaction (review-wide gap). | 0 studies | No studies |
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment Mucosal irritation / oral soft-tissue allergic reaction · Children and adolescents aged 16 years or younger Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | None of the studies reported this outcome. | 0 studies | No studies |
Orthodontic appliances (palatal arch/palatal crib) vs No treatment Sucking cessation (short term) · Children with a non-nutritive sucking habit (digit or pacifier) · Short term (less than 12 months) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | RR 6.53 [1.67, 25.53] | 2 studies · 70 participants | Low |
Pilocarpine hydrochloride (parasympathomimetic) vs Placebo Other oral symptoms (oral discomfort, dysphonia) · Patients with radiation-induced salivary gland dysfunction Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (2015) · Cochrane | Both studies assessed oral discomfort and dysphonia (Johnson 1993; LeVeque 1993); pilocarpine reported to improve associated symptoms of salivary gland dysfunction (oral discomfort, dysphonia). No pooled data. | 2 studies · 278 participants | Ungraded |
Orthodontic appliances (palatal crib) vs No treatment Occlusion (net change in overjet, short term) · Children with a non-nutritive sucking habit (digit or pacifier) · Short term (3 months) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | Table 1 (reduction in malocclusion), Villa 1997 (n=24), palatal crib vs no treatment: net change in overjet (mm) - no treatment 0.02; palatal crib -0.2; no statistically significant net change in overjet between… | 1 study · 24 participants | Ungraded |
Xylitol candy (7.5 g/day) vs Control (sorbitol) candy Caries increment (dmfs, primary and permanent teeth combined) · Children (mixed dentition; baseline about 8 years) · 36 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | One study (252 children) compared xylitol (7.5 g/day) candy with control (sorbitol) candy over 36 months. The data could not be used in analysis because the authors combined primary/deciduous and permanent teeth and… | 1 study · 252 participants | Ungraded |