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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 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 |
|---|---|---|---|
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 studies | No 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 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, No-treatment-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.43 [0.29, 0.57] | 6 studies | Ungraded |
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 studies | No studies |
Breastfeeding vs Bottle feeding Presence of dental caries · Children with exclusively primary dentition (age ≤71 months) Breast and Bottle Feeding as Risk Factors for Dental Caries: A Systematic Review and Meta-Analysis. (2015) | Four studies showed that bottle fed children had more dental caries (p<0.05), while three studies found no such association (p>0.05); the review concluded that breastfeeding can protect against dental caries in early… | 7 studies | Ungraded |
Resin infiltration vs Fluoride varnish, sham/placebo, or flossing advice (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), Resin infiltration Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.19 [0.08, 0.46] | 2 studies | Ungraded |
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 studies | No studies |
Fluoridated milk vs Non-fluoridated milk Caries in primary 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 -1.14 [-1.86, -0.42] | 1 study · 166 participants | Low |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries 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 1.09 [0.42, 2.86] | 1 study · 92 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) Pain · 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): effect not estimable (Analysis 1.2.1; 64 teeth, 32 participants; one study, Hutcheson 2012). | 1 study · 64 participants | 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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Aggressive prostate cancer · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.98 [0.84, 1.15] | 6 studies · 4524 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fasting glucose · Adults with diabetes · Diabetes patients with normal glucose tolerance Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.01 [-0.21, 0.23] | NR | Ungraded |
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 found | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Type 2 diabetes · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.63 [0.56, 0.69] | 16 studies · 72204 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of hypercalcaemia · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 3.80 [0.90, 16.12] | 5 studies · 382 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in femoral neck · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 1.10 [0.40, 1.90] | 8 studies | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in lumbar spine · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.10 [-0.60, 0.70] | 7 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Sporadic colorectal adenoma recurrence · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.87 [0.57, 1.33] | 3 studies · 1366 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Ischaemic heart disease · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | HR 0.72 [0.65, 0.81] | 19 studies · 82982 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures: non-vertebral · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.79 [0.63, 0.99] | 5 studies · 7130 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Small for gestational age · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.54 [0.44, 0.67] | 6 studies · 6851 participants | Ungraded |
Higher circulating 1,25(OH)2D concentration vs Lower circulating 1,25(OH)2D concentration Prostate cancer · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.99 [0.87, 1.14] | 7 studies · 3640 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Breast cancer · Adults (general population) · Premenopausal Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.01 [0.97, 1.06] | 6 studies · 2890 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration All cause mortality · Patients with chronic kidney disease Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.86 [0.81, 0.92] | 10 studies · 6853 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Metabolic syndrome (prevalent) · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.49 [0.38, 0.64] | 8 studies · 31416 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Performance measures: muscle strength · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD -0.19 [-0.35, -0.02] | 3 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Cognition · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.42 [0.34, 0.53] | 7 studies · 9004 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Pre-eclampsia · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.56 [0.39, 0.80] | 9 studies · 3230 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures: non-vertebral, non-hip · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.69 [0.21, 1.66] | 2 studies | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Head circumference · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.05 [-0.24, 0.34] | 2 studies · 840 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Diastolic blood pressure · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -0.03 [-1.98, 1.92] | 3 studies | Ungraded |
Vitamin D supplementation vs Placebo or control Mean gestational age at delivery · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.17 [-0.16, 0.51] | 2 studies | Ungraded |