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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.

Limit to evidence status or GRADE (optional)

10,375 questions in 429 reviews · Oral Health

current versions
No 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.

QuestionEffectEvidenceStatus / 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 participantsUngraded
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 participantsVery 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 participantsUngraded
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 studiesUngraded
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 reported0 studiesNo 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]NRUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesUngraded
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 studyUngraded
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 participantsVery 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 studiesNo 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 extracted13 studiesUngraded
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 studiesUngraded
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 studyUngraded
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 studiesNo 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 studiesUngraded
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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 studiesUngraded
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 participantsModerate
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 studiesNo 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 studiesUngraded
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 participantsVery 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 extracted10 studiesUngraded
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 studiesUngraded
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.NRNo 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 participantsUngraded
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 studiesUngraded
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 participantsUngraded
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 participantsUngraded
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 participantsModerate
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 studiesUngraded
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 participantsUngraded
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 participantsUngraded
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 participantsVery 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]NRUngraded
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 participantsLow
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…NRNo 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 participantsVery 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 participantsVery 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 participantsUngraded
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 participantsVery 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 participantsVery 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 studyUngraded