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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.
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 |
|---|---|---|---|
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, Dysphagia (grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 0.93 [0.83, 1.04] | 3 studies · 1403 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 · 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 | MD -1.5 [-2.11, -0.89] | 2 studies · 85 participants | Low |
EGFR monoclonal antibody (cetuximab or nimotuzumab) plus standard therapy (radiotherapy or chemoradiotherapy) vs Standard therapy alone (radiotherapy or chemoradiotherapy) Quality of life · 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 | Only one study (Bonner 2006, 424 participants) comprehensively assessed quality of life using EORTC QLQ-C30 (v3.0) and QLQ-H&N35; no statistically significant difference between groups for global health status or any… | 1 study · 424 participants | Ungraded |
Psychological intervention (positive reinforcement) vs Alternative psychological intervention (negative reinforcement) 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 | Larsson 1972, comparing positive reinforcement with negative reinforcement, also provided long-term data. Again, no statistically significant between-group differences were shown (Analysis 6.2). | 1 study | Ungraded |
Preformed metal crown (stainless steel), conventional technique vs Aesthetic crown (stainless steel with composite/white veneer), conventional technique Adverse events: bone resorption · Children with decayed primary molar teeth · Six months and four years Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Bone resorption: one case at six months in a tooth treated with a veneer crown; no bone resorption at either the veneer crown or stainless steel sites at four-year follow-up (Analysis 3.2). | 1 study · 11 participants | Very low |
Psychological interventions vs No treatment Occlusion · Children with a non-nutritive sucking habit (digit or pacifier) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | Occlusion: Not reported. | 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, Placebo-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 1.05 [0.91, 1.22] | 11 studies · 6067 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 (moderate to severe) · All patients with cancer who are receiving treatment · Low-dose methotrexate for GVHD prophylaxis after allogeneic HSCT Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | RR 1.01 [0.85, 1.20] | 1 study · 122 participants | Very low |
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) Duration of interruptions to cancer treatment · 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 -8 [-9.26, -6.74] | 1 study · 80 participants | Very low |
Fixed prostheses cemented to prepared teeth after extraction or decoronation 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 |
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, Recombinant interleukin-2 + surgery (De Stefani 2002) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | HR 0.52 [0.31, 0.87] | 1 study · 201 participants | Very low |
Orthodontic appliances (palatal crib) vs No treatment Correction of posterior crossbite · Children with a non-nutritive sucking habit (digit or pacifier) Interventions for the cessation of non‐nutritive sucking habits in children (2015) · Cochrane | Correction of posterior crossbite was not measured in this study despite being a well recognised feature in the malocclusion of a child with a thumb-sucking habit. | 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) Oral mucositis (moderate to severe) · 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 | RR 0.52 [0.41, 0.65] | 5 studies · 444 participants | Moderate |
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 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) Interruptions to cancer treatment (incidence) · 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 | RR 0.44 [0.20, 0.95] | 1 study · 80 participants | Very low |
Implant-supported crowns after extraction or decoronation 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 |
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, all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 1.24 [0.90, 1.70] | 1 study · 30 participants | Ungraded |
Preformed metal crown (stainless steel), conventional technique vs Aesthetic crown (stainless steel with composite/white veneer), conventional technique Adverse events: gingival bleeding · Children with decayed primary molar teeth · Six months and four years Preformed crowns for decayed primary molar teeth (2015) · Cochrane | At six months, none (0/11) of the PMC sites had gingival bleeding, but all (11/11) veneer sites had bleeding, 10 of which bled on probing; statistically significant (McNemar's test, P < 0.001). At four years, one case… | 1 study · 11 participants | Very low |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Caries in deciduous 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 3 to 12 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD -1.81 [-2.31, -1.31] | 9 studies · 44268 participants | Low |
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 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 · Fluorouracil (5FU) treatment for solid cancers Interventions for preventing oral mucositis in patients with cancer receiving treatment: oral cryotherapy (2015) · Cochrane | Adverse events reported narratively (not meta-analysed): one study reported no adverse effects (Katranci 2012); the other four 5FU studies reported low rates of very minor adverse events (headache, chills,… | 5 studies · 444 participants | Ungraded |
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, Stomatitis (rIL-2, grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 1.71 [0.33, 8.83] | 1 study · 30 participants | Ungraded |
Orthodontic appliances (palatal crib) vs No treatment Occlusion (change in overbite, 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 | MD 4.10 [2.93, 5.27] | 1 study · 24 participants | Very low |
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 studies | No studies |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Caries in permanent teeth (change in DMFS) · Children aged about 12 to 16 years (Hardwick 1982), community setting · Follow-up (single study, Hardwick 1982) Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD -2.46 [-3.81, -1.11] | 1 study · 343 participants | Ungraded |
Chlorhexidine varnish (10%) vs Placebo or no treatment Elevated mutans streptococci levels (>=4 with caries screen; high vs low) · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… · 6 to 36 months, permanent dentition Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | RR 0.93 [0.80, 1.07] | 1 study · 496 participants | Very low |
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 Material deficiency (retention/adaptation loss; re-treatment) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 3 years Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | One study (Alkilzy 2011, sealant patch) reported material deficiency: 10% total and 23% partial loss of proximal sealants after three years; 53% maintained perfect margins and none had open margins. No studies reported… | 1 study | Ungraded |
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, Gastrointestinal complaints (BCG-CWP, all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 5.00 [0.27, 94.34] | 1 study · 24 participants | Ungraded |
Pilocarpine hydrochloride (parasympathomimetic) vs Artificial saliva (mucin-based) Adverse effects (side effects; treatment withdrawals) · Patients with radiation-induced salivary gland dysfunction Parasympathomimetic drugs for the treatment of salivary gland dysfunction due to radiotherapy (2015) · Cochrane | Davies 1994: main side effects with pilocarpine were nausea 20%, sweating 15%, lacrimation 10%. One participant definitely withdrew because of side effects; another may have. | 1 study · 20 participants | Ungraded |
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, Mucositis (grades >=3) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 1.20 [0.96, 1.51] | 4 studies · 1495 participants | 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 Improvement in occlusion (Peer Assessment Rating (PAR) or other validated scale) · 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 |
Chlorhexidine varnish (1%, 10% or 40%) vs Placebo or no treatment Caries increment in the primary teeth (d(m)fs/t) · 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 | Two trials with unit of analysis problem. Data imputations indicated no evidence to claim or refute a benefit | 2 studies · 471 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) Adverse events: gingival bleeding · Children with decayed primary molar teeth · Long term (12 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 1.74 [0.99, 3.06] | 2 studies · 195 participants | Low |
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 (deciduous teeth) · People of all ages in a community setting; the included caries studies were all in children aged 3 to 16 years · Follow-up 3 to 12 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD 0.15 [0.11, 0.19] | 10 studies · 39966 participants | Low |
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 (all grades) Interventions for the treatment of oral and oropharyngeal cancers: targeted therapy and immunotherapy (2015) · Cochrane | RR 0.97 [0.91, 1.04] | 3 studies · 1417 participants | Ungraded |
Fluoridated milk vs Non-fluoridated milk Caries in permanent teeth: DMFT (3 years) · General population, irrespective of age or level of risk for dental caries · 3 years Fluoridated milk for preventing dental caries (2015) · Cochrane | MD -0.13 [-0.24, -0.02] | 1 study · 166 participants | Low |
Xylitol wipes (4.2 g/day) vs Control wipes (no xylitol) Adverse effects · Infants (primary teeth) · 12 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. Zhan 2012. | 1 study · 44 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 and adolescents aged 16 years or younger (permanent dentition) · Permanent dentition Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 0.72 [0.46, 1.14] | 1 study · 280 participants | Ungraded |
Oral cryotherapy for 30 minutes vs Oral cryotherapy for 60 minutes Oral mucositis (any severity) · 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 0.89 [0.62, 1.29] | 1 study · 178 participants | Very low |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Patient satisfaction · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… · 5 months after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Patient satisfaction was reported by one trial (Felice 2011); no usable pooled data. | 1 study | Ungraded |
Astra TiO2-blast titanium implants vs ITI SLA titanium implants Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 5 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | No failures; risk ratio not estimable (Akoglu 2011) | 1 study | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Prostate cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 1.04 [0.98, 1.09] | 14 studies · 28988 participants | Ungraded |
IMZ TPS titanium cylinders vs ITI TPS solid titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 5 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 3.00 [0.13, 69.52] | 1 study · 40 participants | Ungraded |
Branemark Mark II turned titanium screws vs ITI TPS solid titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 3 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.05 [0.05, 5.20] | 1 study · 56 participants | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Mandibular ramus growth · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… · End of treatment (about 2 years) Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | The author reported no difference between groups in mandibular ramus growth (linear measure Ar-Go). No pooled estimate. | 1 study | Ungraded |
Powered toothbrush, side-to-side action vs Manual toothbrush Plaque score (>3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Long term (>3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD 0.02 [-0.21, 0.26] | 3 studies · 272 participants | Ungraded |
Bone substitute (anorganic bovine bone / Bio-Oss) vs A different bone substitute Implant failure · Patients undergoing two-stage maxillary sinus augmentation · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 1.00 [0.05, 18.30] | 1 study · 11 participants | Ungraded |
Powered toothbrush, ionic action vs Manual toothbrush Plaque score (1 to 3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Short term (1 to 3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.57 [-0.87, -0.27] | 3 studies · 186 participants | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Stability of anterior open bite correction (1 year after treatment) · 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 studies | No studies |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Alzheimer’s disease · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD (to OR) 0.08 [0.01, 0.63] | 7 studies · 1005 participants | Ungraded |