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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.
75,239 questions in 5,342 reviews
current versionsNo studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%
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 |
|---|---|---|---|
ACP light-cure adhesive vs Control Transbond XT adhesive Enamel demineralization score · Patients undergoing fixed orthodontic treatment · 1 month after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | At T1, the control group had an average demineralization score of 3.39 (±1.29), whereas the ACP group had a notably lower average score of 2.58 (±1.11) (p-value of 0.000). | 1 study · 26 participants | Ungraded |
Physiotherapy (tongue-spatula jaw exercises) vs No active treatment Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD 0.50 [-7.72, 8.72] | 1 study · 24 participants | Very low |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Atraumatic restorative treatment / glass ionomer cement (ART/GIC) Caries arrestment at the individual (patient) level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 3 weeks to 12 months, SDF vs ART(GIC) The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 18.03 [7.34, 44.28] | 1 study · 234 participants | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Periodontal disease prevalence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Periodontal disease affected all ages, was more pronounced in older groups, and ranged from 23% to 99%, generally higher than dental caries; bleeding gum/gingivitis contributed the largest component. | 9 studies | Ungraded |
Superelastic NiTi arch wire vs Multistrand stainless steel arch wire Root resorption · 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 | Root resorption: not reported | 0 studies | No studies |
Poor habit of tooth cleaning vs Good tooth-cleaning habit Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 3.90 [2.761, 5.045] | NR | Ungraded |
Child has a disability (special needs) vs Parents/caregivers of children without disabilities Parental concern / caregiver stress indices (parental perception and parenting stress about the child's oral health) · Parents/caregivers of children with disabilities (special needs; autism spectrum disorder or unspecified disability)… · Cross-sectional Disabilities and Disparities in Oral Health-Related Quality of Life: A Systematic Review and Meta-Analysis… (2024) | SMD 0.43 [0.23, 0.63] | 3 studies · 472 participants | Ungraded |
Thermoelastic copper NiTi (CuNiTi) arch wire vs Conventional NiTi arch wire 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 | MD 0.00 [-0.51, 0.51] | 1 study · 86 participants | Ungraded |
Dental caries (DT not equal to 0) vs No dental caries Periodontitis (prevalence) · Adults · Adjusted OR Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.57 [1.32, 1.86] | 3 studies | Ungraded |
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: USA Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.85 [1.38, 2.49] | 1 study | Ungraded |
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by CDC 2000 growth charts) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 1.18 [0.71, 1.95] | 3 studies · 1377 participants | Very low |
High-intensity sweeteners other than stevia (aspartame, sucralose, saccharin) in food products vs Any comparator (dietary sugar, no treatment, or other sweetener) Effects of non-stevia high-intensity sweeteners (aspartame, sucralose, saccharin) on cariogenic bacteria in dental plaque or saliva · Generally healthy individuals across all age groups Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | No studies on high-intensity sweeteners such as sucralose, saccharin, or aspartame were found; the review located no eligible trials of these sweeteners on cariogenic bacteria. | 0 studies | No studies |
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination Inter-examiner reliability · Children and adults with primary or permanent dentition · Overall Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | no estimate extracted | 13 studies | Ungraded |
Age 8-10 years vs Age >10 years Spontaneous space closure · Children and adolescents with maxillary permanent first molar extraction · Follow-up to complete eruption of the permanent second molar, Maxilla Spontaneous space closure after extraction of permanent first molars in children and adolescents: a… (2024) | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded |
Intervention NR Dental caries (early childhood caries) · Narrative single study (Matee 1994): nocturnal breast-feeding Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 17.8 [6.3, 50.3] | 1 study | 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 dmfs index score · 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 | dmfs was listed in the SoF table but not assessed (not reported for this comparison). | 0 studies | No studies |
Nocturnal breastfeeding vs No nocturnal breastfeeding Dental caries (ECC) · Preschool children under 6 years of age · First dental examination before age 6 years, Cohort studies; sensitivity analysis excluding study 39 Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 3.05 [2.40, 3.87] | 2 studies | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Severity of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 2 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Xylitol chewing gum vs No treatment (no gum / no intervention) Change in Mutans streptococci (MS) count in saliva · Generally healthy individuals across all age groups (infants to elderly) · Post-consumption endpoint (varied durations across trials), Xylitol chewing gum vs no intervention/no gum (3 studies) Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024) | SMD -1.47 [-1.94, -0.99] | 3 studies · 136 participants | Ungraded |
Nocturnal breastfeeding vs No nocturnal breastfeeding Dental caries (early childhood caries) · Preschool children (<6 years) · Cohort studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | RR 2.35 [1.42, 3.89] | 3 studies · 1590 participants | Ungraded |
Minimally invasive caries removal (MIT): selective removal to soft dentin, self-limiting chemomechanical removal, or partial/incomplete caries removal vs Conventional caries removal (CT): selective removal to firm dentin, stepwise excavation, or complete caries removal Pulp exposure rate · Patients with deep carious lesions in permanent (mainly posterior) teeth · 1 to 5 years (follow-up varied by study) Comparative Meta-Analysis of Minimally Invasive and Conventional Approaches for Caries Removal in Permanent… (2024) | Mean pulp-exposure percentage (unweighted study-level mean, 4 studies) MIT 1.2% vs CT 8.1% (Wilcoxon = 0.0, p = 0.068; not statistically significant) | 4 studies · 791 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: systematic random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 30 [15, 44] | 2 studies · 554 participants | Ungraded |
Facemask (RME) or modified facemask vs Other non-surgical orthodontic treatments (mini maxillary protractor, Pushing Splints, modified tandem, Reverse Forsus, reverse Twin Block, reverse chin cup, tongue appliance, Frankel III) Perceived need for surgery in adulthood · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | SoF3: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
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 Mother microbiological presence (high-level mutans streptococci / lactobacilli) · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.53 [0.28, 1.03] | 1 study · 50 participants | Ungraded |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Region: Asian countries Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.70 [1.25, 2.32] | 6 studies | Ungraded |
Silver diamine fluoride (SDF) vs Placebo, control, and/or other interventions Caries arrestment at the surface level · Children and adults without systemic diseases affecting dental health · 12 months to 18 months The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 1.03 [0.47, 2.27] | 3 studies · 5394 participants | Moderate |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 4 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard) Intra-examiner reliability · 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 intra-examiner reliability; narrative synthesis) Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | Intra-examiner reliability (kappa) reported in 6 studies, ranging from 0.52 to 1.00. No pooled estimate. | 6 studies | Ungraded |
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition Caries presence in primary teeth · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… · Children assessed at 4 yrs Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.62 [0.27, 1.39] | 1 study · 96 participants | Very low |
Slum setting vs Non-slum urban setting Dental service utilization · Adults in LMIC urban and slum settings Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | no estimate extracted | 10 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Non-standard periodontitis definition Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.38 [1.07, 1.79] | 2 studies | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Patient satisfaction · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | No studies reported data for this outcome. | NR | No studies |
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR) Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 1-year follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | MD 0.70 [0.25, 1.15] | 1 study · 38 participants | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study location: America/Canada/Brazil RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.11 [0.70, 1.76] | 5 studies | Ungraded |
Postoperative systemic antibiotics (phenoxymethylpenicillin/penicillin VK, 7-day course), partial or total chemo-mechanical debridement and analgesics vs Matched placebo, partial or total chemo-mechanical debridement and analgesics Number of ibuprofen tablets required · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 1.58 [-4.55, 7.71] | 1 study · 41 participants | Ungraded |
Orthodontic removable traction appliance (ORTA) vs Untreated control (no treatment) 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 5.96 [4.71, 7.21] | 1 study · 40 participants | Ungraded |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after subgingival instrumentation (SI) vs Subgingival instrumentation (SI) alone (hand or power-driven, or both), or SI plus placebo/sham aPDT Any adverse effect related to aPDT · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Risk with control: 23 studies reported that no adverse effects of aPDT were observed. Number of participants (studies): 639 (24 studies). Certainty: Moderate. (24 studies reported adverse effects, with all studies… | 24 studies · 639 participants | Moderate |
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo Mother microbiological presence · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | Narrative (Dasanayake 1993; Dasanayake 2002): significant reductions in MS and other bacteria immediately post-treatment; chlorhexidine varnish significantly reduced maternal S. mutans over ~12 months. | 2 studies | Ungraded |
Facemask (with frame internal fixation) vs Frankel III functional appliance 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 0.06 [-0.26, 0.38] | 1 study · 34 participants | Ungraded |
Occlusal splint vs Acupuncture Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 5.54 [-8.06, 19.13] | 2 studies · 67 participants | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (10 weeks), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.13 [0.02, 0.94] | 1 study · 60 participants | Very low |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), PCR-RFLP genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.49 [0.97, 2.27] | NR | Ungraded |
Intralesional steroid injection plus adjunctive treatment vs Intralesional steroid injection alone 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 -0.03 [-2.48, 2.43] | 2 studies · 148 participants | Low |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Quality of life · Adults (> 18 years) with peri-implant mucositis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Only one study reported evidence for adjunctive aPDT in people with peri-implant disease (Al Rifaiy 2022). Data were only available for two outcomes (PPD and BOP), both reported only at three months. No studies… | NR | No studies |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Incidence of new ICLs (mean number of new lesions per subject) · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During fixed orthodontic treatment (development of new lesions), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | MEAN 2.29 [1.12, 3.46] | 5 studies · 208 participants | Very low |
Topical curcumin gel vs Topical aloe vera gel 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 -0.64 [-3.91, 2.63] | 1 study · 60 participants | Very low |
One-step adhesive bonding system (GC Ortho Connect) vs Conventional three-step bonding system (3M Transbond XT) White spot lesion incidence, area, and depth · Patients undergoing fixed orthodontic treatment · 2 and 4 months after treatment start Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Group 3 (GC Ortho Connect) showed a significantly higher incidence than both groups (p < 0.001). Group 3 (GC Ortho Connect) also had larger lesion areas and deeper lesions compared to other groups (p < 0.001). | 1 study · 75 participants | Ungraded |
Package of oral health education/promotion including oral hygiene advice for pregnant women, mothers, infants and young children, plus dietary and feeding practice advice for infants and young children vs Standard care Caries presence in top front four teeth · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 3 yrs, Higher-protein diet trial Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane | RR 0.68 [0.42, 1.10] | 1 study · 226 participants | Very low |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Prevalence of ICLs (mean number of lesions per subject) · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment (cross-sectional/at debonding), Overall (random-effects model) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | MEAN 2.24 [1.79, 2.70] | 6 studies · 484 participants | Very 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, Dental examination: Clinical and radiographic examinations Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 2.21 [2.09, 2.34] | 1 study | Ungraded |