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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 |
|---|---|---|---|
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 (mean severity on WHO 0 to 4 scale) · All patients with cancer who are receiving treatment · Radiotherapy to the head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | MD -0.25 [-0.72, 0.22] | 1 study · 40 participants | Very low |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Direct and indirect costs to participants and health services · 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 direct and indirect costs to participants and health services (review-wide gap). | 0 studies | No studies |
Root canal medications and canal filling, splinting, extraction of teeth, or surgical removal of any relevant pathology vs Each other, placebo, or no treatment Outcome NR · Patients with single and multiple permanent teeth with evidence of any type of external root resorption irrespective… · Any follow-up period Interventions for the management of external root resorption (2015) · Cochrane | None of the studies fulfilled our inclusion criteria and therefore no data analysis was conducted. (Main results: no RCTs that met the inclusion criteria were identified; one ongoing study, NCT00423956, potentially… | 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 Caries increment on permanent whole teeth (D(M)FT), prevented fraction · Children and adolescents aged 16 years or younger (permanent dentition) · Nearest to 3 years, Placebo-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.18 [0.09, 0.27] | 4 studies | Ungraded |
Down syndrome (trisomy 21) vs Individuals without Down syndrome (healthy controls: siblings, schoolchildren or others) Dental caries experience (mean DMFT; permanent teeth) · Individuals of any age (no age limit; ages 1 to 84 years across studies) Association between Dental Caries and Down Syndrome: A Systematic Review and Meta-Analysis. (2015) | SMD -0.18 [-0.35, -0.02] | 6 studies · 718 participants | Ungraded |
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment Proportion of children not remaining caries-free · Children with primary (deciduous) teeth (mostly preschool children aged under 6 years) · Primary dentition Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 0.53 [0.26, 1.07] | 1 study · 145 participants | Ungraded |
Micro-invasive treatment (proximal sealing or resin infiltration): resin sealant, glass ionomer sealant, polyurethane/adhesive patch, or resin infiltration vs Non-invasive measures (e.g. fluoride varnish, flossing/oral hygiene advice), no treatment, or placebo Participant and operator perception · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | None of the studies reported on participant or operator perception | 0 studies | No studies |
Psychological intervention + orthodontic treatment (palatal crib or palatal arch) vs No treatment Adverse events · Children with a non-nutritive sucking habit (digit or pacifier) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | Table 3 (adverse outcomes after one month; Haryett 1967), combined psychological plus orthodontic treatment group: reported upset 4/22 (18%); speech difficulty 6/22 (27%); eating difficulty 6/22 (27%); developing… | 1 study | Ungraded |
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 Patient satisfaction (measured using validated questionnaires or scales) · Individuals of any age receiving orthodontic treatment with fixed appliances (braces) (people requiring orthodontic… Surgical adjunctive procedures for accelerating orthodontic treatment (2015) · Cochrane | Results: 'Our prespecified secondary outcomes of patient satisfaction, improvement in occlusion, and prolonged stability of treatment were not measured in the trials.' | 0 studies | No studies |
Adhesive/polyurethane sealant patch vs No treatment (both arms received flossing plus fluoride toothpaste) 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), Sealant patch Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 1.00 [0.14, 7.23] | 1 study | Ungraded |
Micro-invasive treatment (proximal sealing or resin infiltration): resin sealant, glass ionomer sealant, polyurethane/adhesive patch, or resin infiltration vs Non-invasive measures (e.g. fluoride varnish, flossing/oral hygiene advice), no treatment, or placebo Costs (direct treatment costs; indirect costs / time off school or work) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | None of the studies reported on costs for micro-invasive treatment or non-invasive control | 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 Caries increment on primary (deciduous) tooth surfaces (d(e/m)fs), 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 | PF 0.20 [0.01, 0.38] | 3 studies · 1254 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) Discomfort associated with the procedure · Children with decayed primary molar teeth · At time of dental appointment or within 24 hours Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 0.56 [0.36, 0.87] | 2 studies · 381 participants | Moderate |
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 permanent tooth surfaces (D(M)FS), prevented fraction · Children and adolescents aged 16 years or younger (permanent dentition) · Nearest to 3 years, No-treatment-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.38 [0.24, 0.52] | 10 studies · 2808 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 pain · All patients with cancer who are receiving treatment · Radiotherapy to the head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Oral pain was assessed in this subgroup but the study (Kakoei 2013) did not report details of the scale used, so the data could not be used (no usable estimate). | 1 study | Ungraded |
Fluoride toothpaste containing 10% xylitol vs Fluoride toothpaste (fluoride-only, no xylitol) Caries increment (DFS), prevented fraction at 2.5 to 3 years · Children with permanent teeth (schoolchildren) · 2.5 to 3 years Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | PF 0.13 [0.08, 0.18] | 2 studies · 4216 participants | Low |
Psychological intervention + palatal arch vs Psychological intervention + palatal crib 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 0.30 [0.13, 0.74] | 1 study · 22 participants | Ungraded |
Chlorhexidine mouthrinse 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 studies | No studies |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Overall survival · 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 | HR 0.82 [0.69, 0.97] | 3 studies · 1421 participants | Moderate |
Micro-invasive treatment (proximal sealing or resin infiltration): resin sealant, glass ionomer sealant, polyurethane/adhesive patch, or resin infiltration vs Non-invasive measures (e.g. fluoride varnish, flossing/oral hygiene advice), no treatment, or placebo Caries (lesion) progression measured by pairwise reading of radiographs · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 18 to 36 months (radiographic follow-up) Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.31 [0.18, 0.53] | 4 studies | Moderate |
Non-specific immunotherapy (recombinant interleukin-2 or BCG cell wall preparation) plus standard therapy vs Standard therapy alone Overall survival · People with squamous cell carcinoma of the oral cavity or oropharynx · 24 to 70 months, BCG cell wall preparation + surgery (Bier 1981) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | BCG-CWP + surgery versus surgery alone: 3-year overall survival 10/10 vs 9/10; too few participants to calculate a hazard ratio (Bier 1981, 24 participants). | 1 study · 24 participants | Ungraded |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Disparities in caries across socioeconomic status (SES) · People of all ages in a community setting; the included caries studies were all in children aged 3 to 16 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | There is insufficient information to determine whether initiation of a water fluoridation programme results in a change in disparities in caries levels across SES. Data from 3 observational studies (participants not… | 3 studies · 35399 participants | Low |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Catastrophic failure of the restored tooth or restoration leading directly to extraction · People with a permanent tooth that has undergone endodontic (root canal) treatment · 3 years Single crowns versus conventional fillings for the restoration of root‐filled teeth (2015) · Cochrane | SoF 'Catastrophic failure of restoration': assumed risk (conventional filling) 0, corresponding risk (single crown) 0; no events in either group so a relative effect was not estimable; 117 participants (1 study); GRADE… | 1 study · 117 participants | Very low |
Fluoridated milk vs Non-fluoridated milk Requirement for general anaesthesia due to dental procedures for caries · General population, irrespective of age or level of risk for dental caries Fluoridated milk for preventing dental caries (2015) · Cochrane | No evidence found. (No information was reported by the included study.) | 0 studies | No studies |
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 + radiotherapy vs radiotherapy alone Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | HR 0.70 [0.54, 0.91] | 1 study · 424 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 (any severity) · 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 0.59 [0.35, 1.01] | 5 studies · 270 participants | Low |
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, No-treatment-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 1.03 [0.73, 1.47] | 8 studies · 2628 participants | Ungraded |
Xylitol syrup (high dose, 8 g/day) vs Control (low-dose xylitol, 2.67 g/day) syrup Caries in primary teeth (mean number of decayed primary teeth) · Infants (primary teeth; baseline about 9 to 15 months) · 12 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | PF 0.58 [0.33, 0.83] | 1 study · 94 participants | Low |
Xylitol wipes (4.2 g/day) vs Control wipes (no xylitol) Number of infants with a caries increment (dmfs) · Infants (primary teeth) · 12 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | RR 0.14 [0.02, 1.07] | 1 study · 44 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) Major failure · Children with decayed primary molar teeth · Short term (less than 12 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Short term (less than 12 months): no failures in either group; effect not estimable (Analysis 1.1.1; 76 teeth, 38 participants; one study, Hutcheson 2012). | 1 study · 76 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 in hospital (duration of hospitalisation) · 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 | Summary of findings for the main comparison (5FU solid cancers): Duration of hospitalisation (days) - 'No studies assessed 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, Xerostomia (grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 1.36 [0.80, 2.31] | 2 studies · 1311 participants | 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) Removal of broken (fractured) instruments from the root canal · 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 |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Change in proportion of caries-free children (permanent teeth) · 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 12 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD 0.14 [0.05, 0.23] | 8 studies · 53538 participants | Low |
Resin sealant (one micro-invasive treatment) vs Resin infiltration (another micro-invasive treatment) Caries (lesion) progression (radiographic) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · up to 3 years Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | Only one study (Martignon 2012) directly compared resin sealant versus resin infiltration; the review could not determine which technique is more advantageous and reported no direct effect estimate for this comparison. | 1 study | 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 pain · 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 | MD -1.93 [-2.37, -1.49] | 1 study · 80 participants | Very low |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries 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 |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Major failure · Children with decayed primary molar teeth · 12 months Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 0.12 [0.01, 2.18] | 1 study · 92 participants | Very low |
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) Total time required to complete the clinical procedure · 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 procedure time; such outcomes were only sporadically reported and were never statistically assessed. | NR | No studies |
Fluoridated milk vs Non-fluoridated milk Dental pain due to decay · General population, irrespective of age or level of risk for dental caries Fluoridated milk for preventing dental caries (2015) · Cochrane | No evidence found. (No information was reported by the included study.) | 0 studies | No studies |
Aversive tasting substance applied to digit vs Psychological intervention (habit reversal) 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 0.18 [0.03, 1.24] | 1 study · 29 participants | Ungraded |
Tyrosine kinase inhibitor (erlotinib, gefitinib or lapatinib) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Overall 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 0.99 [0.62, 1.57] | 2 studies · 271 participants | Very low |
Pilocarpine hydrochloride (parasympathomimetic) vs Placebo Salivary flow rates · Patients with radiation-induced salivary gland dysfunction Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (2015) · Cochrane | Only two studies measured salivary flow rates (Johnson 1993; LeVeque 1993); no usable summary/pooled data reported. | 2 studies | Ungraded |
Chlorhexidine gel (0.12%) vs 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 | Neither of these trials reported on the other secondary outcomes such as measures of pain, quality of life, patient satisfaction or direct and indirect costs of interventions. | 0 studies | No studies |
Psychological intervention (habit reversal / positive reinforcement) vs Alternative psychological intervention (DRO / negative reinforcement) 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 | Christensen 1987 (20 participants) compared habit reversal (HR) with differential reinforcement of other behaviour (DRO): no statistically significant difference. Larsson 1972 (38 participants) compared positive with… | 2 studies · 58 participants | Ungraded |
Transplantation of other teeth after extraction of the ankylosed teeth 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 |
Xylitol lozenges (4.7 g/day) vs No treatment Caries increment (DMFS) · Children (permanent teeth; baseline 8 to 10 years) · 24 months (48-month follow-up) Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | PF -0.10 [-0.59, 0.39] | 1 study · 200 participants | Very low |
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, Mucositis (grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 1.22 [0.96, 1.56] | 2 studies · 286 participants | Ungraded |
Xylitol lozenges (5 g/day) vs Control lozenges (sucralose-sweetened placebo, no xylitol) Adverse effects (sores in the mouth, cramps, bloating, constipation, flatulence, loose stool or diarrhoea) · Adults · 33 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | Patterns of adverse effects (sores in the mouth, cramps, bloating, constipation, flatulence, and loose stool or diarrhoea) were similar for both groups. Bader 2013. | 1 study · 669 participants | Ungraded |
Xylitol tablets (200 to 600 mg/day) via slow-release pacifier/dummy vs Control (sorbitol) tablets Number of infants with a caries increment (dmfs) · Infants (primary teeth; from about 1 month of age) · 24 months (48-month follow-up) Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | RR 3.08 [0.69, 13.65] | 1 study · 62 participants | Very low |