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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 |
|---|---|---|---|
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
Fluoridated milk vs Non-fluoridated milk Antibiotics due to dental infections · 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 |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Discomfort associated with the procedure · Children with decayed primary molar teeth · Immediately after treatment Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 1.67 [0.65, 4.25] | 1 study · 104 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 Adverse events · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 1 to 3 years Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | The four studies that measured adverse events reported no adverse events after micro-invasive treatment (no events in either arm) | 4 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 Tooth staining · 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 on staining of tooth surfaces (not even Gisselsson 1999, the only trial testing stannous fluoride). | 0 studies | No studies |
Chlorhexidine varnish (10% and 40%) vs Placebo or no treatment Caries increment in permanent dentition (DMFS; higher values indicate greater caries) · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… · 30 to 36 months, permanent dentition Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | MD 0.53 [-0.47, 1.53] | 2 studies · 690 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 Caries (lesion) progression (radiographic; most sensitive measure per study, DSR > pairwise > visual scoring) · 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) Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.24 [0.14, 0.41] | 7 studies · 365 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 Signs of acute toxicity during gel application (nausea, gagging, vomiting) · Children and adolescents aged 16 years or younger · During gel application Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RD 0.01 [-0.01, 0.02] | 2 studies · 490 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 Change in decayed, missing and filled (DMF/dmf) figures at surface, tooth and whole mouth level · 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 | No studies reported on caries measured as change in decayed, missing and filled (DMF/dmf) figures at surface, tooth or whole mouth level | 0 studies | No studies |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Periodontal health status · 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 | No data were reported nor measured by the study. The abstract confirms no evidence was available for any secondary outcome. | NR | 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 Proportion of children developing new caries · Children and adolescents aged 16 years or younger (permanent dentition) Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 0.82 [0.68, 0.99] | 1 study · 280 participants | Ungraded |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Non-catastrophic failure of the post · 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 | RR 1.96 [0.18, 21.01] | 1 study · 117 participants | Very low |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Incidence or recurrence of caries (assessed clinically or by radiographs) · 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 | No data were reported nor measured by the study. The abstract confirms no evidence was available for any secondary outcome. | NR | 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) | OR 0.43 [0.23, 0.80] | 2 studies · 620 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 Caries (lesion) progression measured by digital subtraction radiography (DSR) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 12 to 18 months (radiographic follow-up) Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.18 [0.06, 0.50] | 3 studies | 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 radiographic scoring · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 12 to 30 months (radiographic follow-up) Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.27 [0.17, 0.44] | 5 studies | Moderate |
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water Caries in deciduous teeth (dmft/dmfs) · 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 caries in deciduous teeth. No included study reported change in dmft following cessation. | 0 studies | No studies |
Higher water fluoride concentration (fluoridated water; natural or artificial) vs Lower water fluoride concentration (concurrent control) Dental fluorosis of any level (all severities) · 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 3.60 [2.86, 4.53] | 90 studies · 180530 participants | Low |
Chlorhexidine spray 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 |
Chlorhexidine toothpaste 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 |
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 · Long term (12 months to 48 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 0.18 [0.06, 0.56] | 3 studies · 346 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 Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.28 [0.19, 0.36] | 25 studies · 8479 participants | Moderate |
Xylitol sucking tablets (1 g/day) vs No treatment Caries increment (dmfs) · 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 | PF 0.53 [0.001, 1.04] | 1 study · 118 participants | Very low |
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water Caries in permanent teeth (DMFS) · People of all ages in a previously fluoridated community (Maupome 2001: children with generally low caries experience) · Follow-up 3 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | Insufficient evidence to determine the effect of the cessation of water fluoridation on caries. One study (Maupome 2001), at high risk of bias, over 3 years found no increase in caries in the fluoride-ended group… | 1 study · 9249 participants | Very low |
Resin sealant (with or without flossing advice) vs 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 sealant Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.33 [0.18, 0.59] | 2 studies | Ungraded |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Non-catastrophic failure of the restoration (requiring further treatment) · 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 | RR 0.33 [0.04, 3.05] | 1 study · 117 participants | Very low |
Down syndrome (trisomy 21) vs Individuals without Down syndrome (healthy controls: siblings, schoolchildren or others) Dental caries (presence vs absence; all teeth, deciduous and permanent) · 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) | OR 0.36 [0.22, 0.57] | 2 studies · 314 participants | Ungraded |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Satisfaction with treatment · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Satisfaction with treatment: No evidence available (Summary of findings 2). | 0 studies | No studies |
Xylitol lozenges (4.7 g/day) vs No treatment Number of children with a caries increment · 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 | RR 1.02 [0.83, 1.26] | 1 study · 200 participants | Ungraded |
Micro-invasive treatment (proximal sealing or resin infiltration) vs Conventional invasive treatment (restoration / drill and fill) Outcome NR · 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 | No studies compared micro-invasive treatments with invasive treatment (fillings) | 0 studies | No studies |
Chlorhexidine gel (0.12%) vs No treatment Presence of new caries in the primary teeth · 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 | RR 1.00 [0.36, 2.77] | 2 studies · 487 participants | Very low |