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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 |
|---|---|---|---|
Silver diamine fluoride (SDF) plus fluoride varnish vs Sealants plus fluoride varnish (with or without restorations) Adverse effects · Children and adults (with or without carious lesions) · Study period (24 months), Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Ruff 2022 reported that there were no adverse events during the study period; adverse events were not defined by the study authors. Assumed data available for 1398 participants. | 1 study · 1398 participants | Very low |
Male sex vs Female sex Spontaneous space closure · Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Mandible Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 1.38 [0.37, 5.14] | 2 studies | Ungraded |
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard) Specificity · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), Overall (studies reporting specificity; narrative synthesis) Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | Specificity ranged from 83% to 100% across studies (reported in 13 of 19 studies). No pooled estimate; meta-analysis not performed. | 13 studies | Ungraded |
Dietary advice on how to achieve a healthy diet for infants (tailored advice focused on a diet low in saturated fat and cholesterol intake) vs Standard care Mother plaque (sub- and supragingival calculus) · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.92 [0.62, 1.37] | 1 study · 133 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: North America A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.89 [1.62, 6.16] | 7 studies | Ungraded |
Silver diamine fluoride (SDF) vs Placebo or no treatment Primary caries prevention · Children and adults (with or without carious lesions) · 24 to 36 months, Permanent dentition (root) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | MD -0.79 [-1.40, -0.17] | 3 studies · 439 participants | Moderate |
Cdx-2(rs11568820) A allele / genotype vs G allele / reference genotype Dental caries · Children (<18 years) with vs without dental caries · Not meta-analyzed (single study) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | Cdx-2(rs11568820) was reported by only one study (Qin 2019; 303 caries, 245 caries-free) and was therefore not subjected to meta-analysis (Results 'Meta-analysis'; Table 6). | 1 study · 548 participants | Ungraded |
Fluoride toothpaste less than 1000 ppm (lower concentration) vs Fluoride toothpaste 1000 ppm or more (higher concentration) Fluorosis (percentage prevalence in permanent teeth) · Children exposed to topical fluoride when under 6 years old; fluorosis assessed in permanent teeth at 6 to 18 years · Fluorosis assessed when most permanent teeth of interest had erupted (6 to 18 years) Topical fluoride as a cause of dental fluorosis in children (2024) · Cochrane | OR 0.79 [0.62, 1.02] | 3 studies · 2037 participants | Very low |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.01 [0.83, 1.21] | 6 studies · 1986 participants | Ungraded |
Intervention NR Dental caries in children · Children's age subgroup: 2 to 4 years Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.20 [1.04, 1.36] | 4 studies | Ungraded |
Silver diamine fluoride (SDF) vs Restoration (restorative treatment) Caries arrest · Children and adults (with or without carious lesions) · 12 months, Primary dentition (coronal) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 0.03 [0.01, 0.10] | 1 study · 98 participants | Very low |
Overweight vs Normal weight (eutrophic) Dental caries experience (dmft), continuous · Brazilian children in primary dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | MD 0.31 [-0.10, 0.73] | 2 studies · 734 participants | Very low |
Occlusal splint vs Pharmacological therapy Muscle pain at rest · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Silver diamine fluoride (SDF) vs Placebo, control, and/or other interventions Caries arrestment at the individual level · Children and adults without systemic diseases affecting dental health · 3 weeks to 12 months The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 3.86 [0.34, 43.96] | 5 studies · 720 participants | Low |
Maternal smoking during pregnancy vs No maternal smoking during pregnancy Dental caries in children · Children of mothers assessed for smoking status during pregnancy (early childhood dental caries) · Exposure during pregnancy; caries assessed in early childhood, Study region: Asia Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.71 [1.40, 2.10] | 5 studies | Ungraded |
TT+TG genotypes vs GG genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TG vs GG) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.09 [0.76, 1.58] | 3 studies · 796 participants | Ungraded |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), Asian ethnicity Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.98 [0.65, 1.50] | NR | Ungraded |
Intervention NR Change in Lactobacillus spp. in dental plaque · Single study (Ly et al. 2008), xylitol or maltitol, not pooled Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | Narrative (no effect size) No significant change in Lactobacillus spp. after xylitol or maltitol consumption | 1 study | Ungraded |
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish Adverse effects · Children and adults (with or without carious lesions) · 6 months Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Parents were asked if any harm was noticed due to the use of SDF, but the results were not reported in the study report; we could not determine whether there were any associated harms with either treatment (Mendiratta… | 1 study | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.58 [-7.09, 5.93] | 1 study · 20 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints ANB (ANPog) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 1.40 [0.29, 2.51] | 1 study · 42 participants | Ungraded |
ACP light-cure adhesive vs Control Transbond XT adhesive Enamel demineralization score · Patients undergoing fixed orthodontic treatment · 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | At T2, the control group had an average score of 4.32 (±2.32), while the ACP group continued to exhibit a lower average score of 3.41 (±1.11) (p-value of 0.000). | 1 study · 26 participants | Ungraded |
Periodontitis vs No periodontitis High salivary P. gingivalis (over 10^4 CFU/ml) · Adults · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 3.38 [1.46, 7.83] | 2 studies | Ungraded |
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material Primary caries prevention · Children and adults (with or without carious lesions) · Primary and permanent dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported this outcome | 0 studies | No studies |
Second molar at Demirjian stage E at extraction vs Second molar at Demirjian stage F-H at extraction Spontaneous space closure · Children and adolescents after extraction of a maxillary permanent first molar (before eruption of the second molar) · Until eruption of the permanent second molar (median follow-up 4.0 years), Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR 4.78 [1.56, 14.66] | 3 studies · 252 participants | Low |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Depression · People with temporomandibular disorders (TMD) · Short term, Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.58 [-4.62, -0.54] | 1 study · 32 participants | Ungraded |
Er:YAG laser irradiation vs Untreated / high-speed-handpiece control enamel Enamel resistance to demineralization (microhardness / lesion depth) · Human enamel adjacent to restorations or in pits and fissures (in situ / ex vivo) Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | Narrative only (not meta-analyzed). Colucci: Er:YAG laser feasible for controlling caries progression adjacent to restorations but not able to prevent caries formation (optimum 2 Hz). Correa-Afonso: Er:YAG did not… | 2 studies | Ungraded |
Oral health education/promotion (oral hygiene advice plus diet and feeding practice advice) combined with clinical treatment for mother's dentition (basic restorative and preventive; 1 trial included CHX varnish application) vs Standard care dmft index score · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… · Children assessed at 18 months Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | The mean dmft index score was 0.52 (standard care) versus 0 (advice + treatment group); relative effect not estimable; 50 participants (1 study); very low-certainty evidence. | 1 study · 50 participants | Very low |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish Adverse effects · Children and adults (with or without carious lesions) · 18 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Gao 2019 noted that "arrested lesions were stained black" (reported with no associated data). No other adverse effects observed, and no reports from parents of systemic disease. | 1 study · 1070 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Facemask with alternating rapid maxillary expansion and constriction (Alt-RAMEC) Wits appraisal · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.38 [-1.37, 0.60] | 3 studies · 97 participants | Ungraded |
Prenatal vitamin D deficiency (PVDD) vs Normal or sufficient prenatal vitamin D level Dental caries prevalence · Children aged 2 to 8 years · Maternal pregnancy to child age 2 to 8 years, Children of mothers with sufficient prenatal vitamin D Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | Proportion 0.25 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · GNI $10000-$19999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.04 [2.39, 5.68] | 9 studies | Ungraded |
Oral cancer patients (cases) vs Healthy controls DMFT index in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, DMFT (decayed, missing, filled teeth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.65 [0.12, 1.18] | 2 studies | Ungraded |
Jaw opening exercises alone vs Ultrasound plus jaw opening exercises Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -3.70 [-11.53, 4.13] | 1 study · 20 participants | Very low |
Mandibular headgear vs Chin cup ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | Arun 1994 (n=60): ANB data not usable (no SDs; Mann-Whitney); no statistically significant difference between interventions (P>0.05). | 1 study · 60 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -7.56 [-14.50, -0.63] | 2 studies · 75 participants | Ungraded |
Occlusal splint vs Acupuncture Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.80 [-7.36, 8.96] | 1 study · 30 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Mature teeth, partial pulpotomy, irreversible pulpitis Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.808 [0.723, 0.881] | 5 studies | Ungraded |
Cranberry extract / juice and proanthocyanidin (flavonoid) fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride) Biofilm morphological changes · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | Cranberry treatment disrupted biofilm integrity with agglutination/cell degradation at higher concentrations (Singhal), reduced polymicrobial biomass 38% at 96 h (Philip 2019), produced defective accumulation and… | 4 studies | Ungraded |
Intervention NR Spontaneous space closure · Maxilla: M2 Demirjian A-D vs G-H Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 | 1 study | Ungraded |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), Mixed dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.80 [0.55, 1.15] | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 5.18 | NR | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Change in probing depth (PD/PPD) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD -0.10 [-0.57, 0.37] | 1 study · 38 participants | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (mean 3 months), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.17 [0.02, 1.26] | 1 study · 40 participants | Very low |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study location: Europe RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.48 [0.83, 2.63] | 5 studies | Ungraded |
Surgical miniplates with facemask vs Surgical miniplates with Class III elastics ANB · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.05 [-1.24, 1.14] | 1 study · 20 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Gini index: no inequality A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -30.92 [-31.57, -30.27] | 1 study · 400 participants | Moderate |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Time to next/working arch wire · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | No studies reported time to next/working arch wire | 0 studies | No studies |
Facemask vs Untreated control (no treatment) Self-esteem (Piers-Harris self-concept scale) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 6-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD -0.30 [-4.17, 3.57] | 1 study · 65 participants | Ungraded |