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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 |
|---|---|---|---|
Intervention NR Enamel surface properties (thinner, softer enamel) in exfoliated teeth · By race/ethnicity Social-Biological Interactions in Oral Disease: A 'Cells to Society' View. (2016) | Narrative (no effect size) Higher salivary cortisol reactivity associated with thinner, softer enamel surfaces | 1 study | Ungraded |
Adhesively bonded amalgam restorations in conventional preparations utilising deliberate retention (all bonding agents) vs Traditional non‐bonded amalgam restorations Post‐insertion sensitivity or pain assessed by a validated pain scale · Adults and adolescents with permanent posterior molar and premolar teeth suitable for Class I and II, but excluding… · Baseline and 24 months Adhesively bonded versus non‐bonded amalgam restorations for dental caries (2016) · Cochrane | Post‐insertion sensitivity or pain assessed by a validated pain scale - not measured | See comment | See comment | Not estimable | - | See comment | No study addressed this outcome | 1 study · 31 participants | Ungraded |
High-viscosity glass-ionomer cement (HVGIC) fissure sealant placed by press-finger technique vs Resin-based fissure sealant Development of carious lesions on sealed occlusal pits and fissures · Children with fully erupted permanent first molar teeth (mean age about 6 to 8 years) · 36 months Caries-Preventive Effect of High-Viscosity Glass Ionomer and Resin-Based Fissure Sealants on Permanent… (2016) | RR 0.90 [0.49, 1.67] | 3 studies · 600 evaluated sealed teeth participants | Ungraded |
Laser (Er:YAG, Er,Cr:YSGG, or Nd:YAG) vs Conventional mechanical caries removal (standard drill; handpiece with a bur) Need for anaesthesia · Children, adolescents and adults with caries in deciduous and permanent teeth (age 3.5 to 84 years) · during treatment, overall (children and adults) Lasers for caries removal in deciduous and permanent teeth (2016) · Cochrane | RR 0.37 [0.19, 0.72] | 4 studies · 320 participants | Ungraded |
Intervention NR Dental caries prevalence in permanent teeth (cavitated lesions) · Children aged 11-13 years in Latin America and the Caribbean · Studies with data collected after 2000 (21st century) Does the Decline in Caries Prevalence of Latin American and Caribbean Children Continue in the New Century?… (2016) | Prevalence 0.58 [0.54, 0.61] | 63 studies · 95188 participants | Ungraded |
Fluoride mouthrinse (any fluoride agent, concentration, volume, frequency or technique; swished and expectorated, not swallowed) vs Placebo or no treatment Proportion of children not remaining caries-free · Children or adolescents aged 16 years or younger at the start of the study · At least 1 year/school year Fluoride mouthrinses for preventing dental caries in children and adolescents (2016) · Cochrane | None of the trials reported data on the proportion of children not remaining caries-free. | 0 studies | No studies |
High-viscosity glass-ionomer cement (HVGIC) fissure sealant placed by press-finger technique vs Resin-based fissure sealant Development of carious lesions on sealed occlusal pits and fissures · Children with fully erupted permanent first molar teeth (mean age about 6 to 8 years) · 24 months Caries-Preventive Effect of High-Viscosity Glass Ionomer and Resin-Based Fissure Sealants on Permanent… (2016) | RR 1.36 [0.66, 2.78] | 4 studies · 1742 evaluated sealed teeth participants | Ungraded |
Low socioeconomic position and adverse behavioural factors vs Higher socioeconomic position and fewer adverse behaviours Systemic inflammation (C-reactive protein) and periodontal disease progression · General-population adults (German cohort) · 5-year follow-up Social-Biological Interactions in Oral Disease: A 'Cells to Society' View. (2016) | no estimate extracted | 1 study · 3300 participants | Ungraded |
Dementia vs Older people without dementia Missing teeth · Older people with dementia Oral health and orofacial pain in older people with dementia: a systematic review with focus on dental hard… (2016) | MEAN Without dementia 9.3 to 28.2; with dementia 10.2 to 27.3 (mean number of missing teeth) | 10 studies | Ungraded |
Laser (Er:YAG, Er,Cr:YSGG, or Nd:YAG) vs Conventional mechanical caries removal (standard drill; handpiece with a bur) Need for anaesthesia · Children, adolescents and adults with caries in deciduous and permanent teeth (age 3.5 to 84 years) · during treatment, children/adolescents Lasers for caries removal in deciduous and permanent teeth (2016) · Cochrane | RR 0.25 [0.10, 0.65] | 3 studies · 217 participants | Low |
Fluoride mouthrinse (any fluoride agent, concentration, volume, frequency or technique; swished and expectorated, not swallowed) vs Placebo or no treatment Tooth staining/discolouration (adverse effect) · Children or adolescents aged 16 years or younger at the start of the study · At least 1 year/school year Fluoride mouthrinses for preventing dental caries in children and adolescents (2016) · Cochrane | Study 1: "significant difference" in stain score (from the control) in the group using an amine fluoride mouthrinse; "non-significant difference" (from the control) in the group using sodium fluoride. In 2 trials where… | 3 studies | Very low |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Costs for the use of different treatment interventions · 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 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 Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.32 [0.19, 0.46] | 10 studies | Ungraded |
Chlorhexidine gel (0.12%) vs No treatment Mutans streptococci prevalence (presence/absence) · 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 1.26 [0.95, 1.66] | 2 studies · 490 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 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, Placebo-controlled trials Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | PF 0.21 [0.15, 0.28] | 15 studies · 5671 participants | Ungraded |
Xylitol lozenges (4.7 g/day) vs No treatment Adverse effects · 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 | There were no usable data presented for adverse effects. Lenkkeri 2012. | 1 study | Ungraded |
Fluoride toothpaste containing 10% xylitol vs Fluoride toothpaste (fluoride-only, no xylitol) Adverse effects · Children with permanent teeth (schoolchildren) · 2.5 to 3 years Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | Adverse effects: both studies reported that there were no adverse effects in either the xylitol or control group. | 2 studies · 4216 participants | Ungraded |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Dental caries in adults · Adults · Adults Water fluoridation for the prevention of dental caries (2015) · Cochrane | No studies that aimed to determine the effectiveness of water fluoridation for preventing caries in adults met the review's inclusion criteria. There are no data to determine the effect of water fluoridation on caries… | 0 studies | No studies |
Chlorhexidine oral product (one formulation/concentration) vs Another chlorhexidine formulation, concentration or application frequency Outcome NR · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | no estimate extracted | 0 studies | No studies |
Chlorhexidine gel (0.12%) vs No treatment Adverse events · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… · 24 months, primary dentition Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | Both studies reported there were no adverse events. | 2 studies | Ungraded |
Higher water fluoride concentration (fluoridated water; natural or artificial) vs Lower water fluoride concentration (concurrent control) Dental fluorosis of aesthetic concern (Dean's Index, TFI, TSIF) · Populations of all ages (mostly children) exposed to drinking water with differing fluoride concentrations · Cross-sectional Water fluoridation for the prevention of dental caries (2015) · Cochrane | OR 2.90 [2.05, 4.10] | 40 studies · 59630 participants | Low |
Xylitol sucking tablets (1 g/day) vs No treatment Number of infants with a caries increment · Infants/young children (primary teeth; baseline about 1 to 3 years) · 18 months (24-month follow-up) Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | RR 0.72 [0.35, 1.45] | 1 study · 118 participants | Ungraded |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Cost · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Cost · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
Xylitol lozenges (5 g/day) vs Control lozenges (sucralose-sweetened placebo, no xylitol) Caries increment (DFS) · Adults · 33 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | PF 0.08 [-0.03, 0.20] | 1 study · 669 participants | Low |
Initiation of water fluoridation (artificial or natural) vs Low/non-fluoridated water (0.4 ppm fluoride or less) Caries in permanent teeth (change in DMFT) · People of all ages in a community setting; the included caries studies were all in children aged 3 to 16 years · Follow-up 8 to 11 years Water fluoridation for the prevention of dental caries (2015) · Cochrane | MD -1.16 [-1.61, -0.72] | 10 studies · 78764 participants | Low |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Adverse events: gingival bleeding · Children with decayed primary molar teeth · Short term (up to 12 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 1.69 [0.61, 4.66] | 2 studies · 226 participants | Ungraded |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Satisfaction with treatment · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Satisfaction with treatment: listed in the Summary of findings table with no data; the studies did not measure this outcome. | 0 studies | No studies |
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment Unacceptability of treatment (dropouts/exclusions during the trial) · Children and adolescents aged 16 years or younger · During trial Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | RR 1.03 [0.89, 1.19] | 19 studies | Ungraded |
Single full-coverage metal-ceramic crown over composite core and post vs Direct adhesive composite restoration with post (conventional filling, no crown) Patient satisfaction and quality of life (any validated instrument) · People with a permanent tooth that has undergone endodontic (root canal) treatment Single crowns versus conventional fillings for the restoration of root‐filled teeth (2015) · Cochrane | This outcome was not reported nor measured by the study. The abstract confirms no evidence was available for any secondary outcome. | NR | No studies |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Pain · Children with decayed primary molar teeth · Long term (12 months to 24 months) Preformed crowns for decayed primary molar teeth (2015) · Cochrane | RR 0.15 [0.04, 0.67] | 2 studies · 312 participants | Moderate |
Fluoridated milk vs Non-fluoridated milk Adverse effects: dental fluorosis · General population, irrespective of age or level of risk for dental caries Fluoridated milk for preventing dental caries (2015) · Cochrane | No evidence found. (Correspondence with the author (Maslak 2004) confirmed that no adverse effects were reported.) | 0 studies | No studies |
Glass ionomer sealant (with fluoride gel plus dentifrice) vs Fluoride gel plus fluoride toothpaste/dentifrice (non-invasive control) Caries (lesion) progression (radiographic) · Dentate children and adults with non-cavitated proximal caries lesions extending into enamel or dentine (not pulp) in… · 12 to 36 months (radiographic follow-up), Glass ionomer sealant Micro‐invasive interventions for managing proximal dental decay in primary and permanent teeth (2015) · Cochrane | OR 0.13 [0.01, 2.52] | 1 study | Ungraded |
Xylitol syrup (high dose, 8 g/day) vs Control (low-dose xylitol, 2.67 g/day) syrup Adverse effects (loose stools, diarrhoea) · Infants (primary teeth; baseline about 9 to 15 months) · 12 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | Adverse effects were not reported in a usable format, but the reported rates of loose stools and diarrhoea were very similar between groups. There were no serious adverse effects during the study. Milgrom 2009. | 1 study · 94 participants | Ungraded |
Cessation of water fluoridation (fluoride removed from the water supply) vs Continued fluoridated water Change in proportion of caries-free children (deciduous or permanent teeth) · People of all ages in a previously fluoridated community (Maupome 2001: children with generally low caries experience) Water fluoridation for the prevention of dental caries (2015) · Cochrane | No evidence to determine the effect of the cessation of water fluoridation on the proportion of caries-free children. | 0 studies | No studies |
Preformed crown (any material; conventional technique or Hall Technique) vs No treatment Outcome NR · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Crown versus no treatment was a planned comparison (Comparison 2: crown versus no crown or filling). No study evaluated crown versus no treatment; the only study in this comparison (Santamaria 2014) used active… | 0 studies | No studies |
Preformed metal crown (fitted using the Hall Technique) vs Non-restorative caries treatment Pain · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | Pain: No evidence available (Summary of findings 2). | 0 studies | No studies |
Preformed crown (any material; conventional technique or Hall Technique) vs Filling (any material; with or without complete carious tissue excavation; with or without pulp treatment) Time to restoration failure/retreatment · Children with decayed primary molar teeth Preformed crowns for decayed primary molar teeth (2015) · Cochrane | The studies did not measure this outcome. | 0 studies | No studies |
Chlorhexidine varnish vs Placebo or no treatment Adverse events (e.g. ulcers, tooth staining) · Children and adolescents below 18 years at study start (included studies: children from birth to 15 years), with… Chlorhexidine treatment for the prevention of dental caries in children and adolescents (2015) · Cochrane | One study reported no adverse events for ulcers or tooth staining. One study stated "side-effects due to the CHX treatment were not noted". | 2 studies | Ungraded |
Xylitol candy (7.5 g/day) vs Control (sorbitol) candy Adverse effects · Children (mixed dentition; baseline about 8 years) · 36 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | The authors reported that there were no adverse effects for either group. Honkala 2014. | 1 study · 252 participants | Ungraded |
Fluoride gel (topically applied; operator- or self-applied; any fluoride agent/concentration; frequency at least once a year) vs Placebo or no treatment Mucosal irritation / oral soft-tissue allergic reaction · Children and adolescents aged 16 years or younger Fluoride gels for preventing dental caries in children and adolescents (2015) · Cochrane | None of the studies reported this outcome. | 0 studies | No studies |
Xylitol candy (7.5 g/day) vs Control (sorbitol) candy Caries increment (dmfs, primary and permanent teeth combined) · Children (mixed dentition; baseline about 8 years) · 36 months Xylitol‐containing products for preventing dental caries in children and adults (2015) · Cochrane | One study (252 children) compared xylitol (7.5 g/day) candy with control (sorbitol) candy over 36 months. The data could not be used in analysis because the authors combined primary/deciduous and permanent teeth and… | 1 study · 252 participants | Ungraded |
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 |
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 |