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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 |
|---|---|---|---|
Oral cancer patients (cases) vs Healthy controls Alveolar bone loss (ABL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, ABL (alveolar bone loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.18 [-2.34, 2.69] | 2 studies | Ungraded |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Primary caries prevention · Children and adults (with or without carious lesions) · 18 months, Permanent dentition (coronal) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 1.76 [0.74, 4.20] | 1 study · 242 participants | Very low |
Overweight/obesity (combined) vs Normal weight (eutrophic) Dental caries prevalence (any DMFT), dichotomous · Brazilian children/adolescents in permanent dentition (BMI classified by WHO 2007 Z-score) Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and… (2024) | OR 0.93 [0.78, 1.12] | 2 studies | Low |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Root caries · Adults · Root caries Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 2.10 [1.03, 4.29] | 4 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Use of toothbrush and toothpaste for mouth cleaning · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum/disadvantaged/rural vs non-slum/urban Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Eleven studies addressed practices; toothbrush and toothpaste were the commonest cleaning method but their use was lower among slum/disadvantaged/rural groups than non-slum/urban groups (e.g., Osuh 78% slum vs 94%… | 11 studies | Ungraded |
Intervention NR Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF during sleep Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | AOR 6.5 | 1 study | 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: Asia-Oceania A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.87 [2.84, 4.91] | 30 studies | Ungraded |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Permanent dentition Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.36 [0.89, 2.08] | NR | 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 Mother microbiological presence (mutans streptococci colonisation level, CFU/mL) · 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 | MD 0.50 [0.15, 0.85] | 1 study · 126 participants | Ungraded |
Prenatal vitamin D deficiency measured at 6 to 38 gestational weeks vs Normal or sufficient prenatal vitamin D level Dental caries · Children aged 2 to 8 years · Maternal gestational weeks 6 to 38, Vitamin D measurement at 6 to 38 gestational weeks Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.32 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: simple random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 42 [35, 49] | 4 studies · 1421 participants | Ungraded |
Full pulpotomy vs Partial pulpotomy Overall success (composite of clinical and radiographic success) · Mature permanent teeth with symptomatic irreversible pulpitis and carious pulp exposure · >=12 months Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | OR 2.16 [0.92, 5.07] | 3 studies | Ungraded |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Primary caries prevention · Children and adults (with or without carious lesions) · Primary dentition Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data in this dentition type | 0 studies | No studies |
Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars Midline deviation of the mandibular arch · 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 11.6 [1.9, 70.3] | 1 study | 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 defs index score (categories) · 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 | Thorild 2003 defs score categories (very low-certainty): 1-3 defs RR 0.48 (95% CI 0.15 to 1.54); 3-4 defs RR 0.85 (95% CI 0.18 to 3.98); >=5 defs RR 0.28 (95% CI 0.01 to 6.78); 96 participants. | 1 study · 96 participants | Very low |
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) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | Ungraded |
Mineral trioxide aggregate (MTA) vs Calcium hydroxide (CH) Overall success (composite of clinical and radiographic success) · Permanent teeth with carious pulp exposure · >=12 months, Partial pulpotomy Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | OR 2.81 [1.38, 5.74] | NR | 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, Overall (all 12 studies pooled) Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.774 [1.554, 2.026] | 12 studies · 90405 participants | Ungraded |
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control) Gingival index · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 3.07 months, Overall (all presentations pooled) Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD 0.04 [-0.18, 0.27] | 3 studies · 144 participants | Low |
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents Bacterial growth inhibition · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 5 studies | Ungraded |
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate) Association between patient age and number of ICLs · Patients (permanent dentition) during or after fixed orthodontic treatment with fixed (multibracket) appliances · During or after fixed orthodontic treatment, By patient age (subgroup meta-analysis; no significant association) Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024) | No significant association found between patient age and the number of ICLs (meta-regression / subgroup analysis) | NR | Ungraded |
Absence of toothpaste use vs Toothpaste use Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 1.42 [-1.278, 4.109] | NR | Ungraded |
Reduction in previous year's academic score vs No reduction in academic score Reduction in previous year's academic score · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 5.51 [1.952, 9.066] | NR | Ungraded |
Second molar at Demirjian stage F-G at extraction vs Second molar at Demirjian stage D-E at extraction 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 0.68 [0.28, 1.66] | 4 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Partial pulpotomy, mature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.842 [0.745, 0.921] | 6 studies | Ungraded |
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC), Real-time quantitative PCR genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.52 [1.10, 2.10] | NR | Ungraded |
CO2 laser irradiation (0.4 to 5 W) vs Untreated control enamel Enamel surface / cross-sectional microhardness · Human / bovine enamel specimens under cariogenic challenge (in situ / ex vivo) Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | MD 49.55 [37.74, 61.37] | 3 studies · 64 participants | Ungraded |
Prenatal vitamin D deficiency (low maternal 25(OH)D during pregnancy) vs Adequate prenatal vitamin D (sufficient maternal 25(OH)D) Dental caries in children · Children aged 6 to 8 years whose mothers' prenatal vitamin D status was assessed · Prenatal exposure; dental caries at 6 to 8 years, Children's age subgroup: 6 to 8 years Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.07 [0.84, 1.30] | 1 study | Ungraded |
T allele vs C allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (T vs C), PCR-RFLP genotyping Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.79 [0.60, 1.04] | NR | Ungraded |
Intervention NR Future caries prediction · Children without previous caries history A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2024) | S. mutans and other acid-producing species did not predict future caries (null; no estimate) | 1 study | Ungraded |
Breastfeeding (exclusive or partial, any duration) vs No breastfeeding Dental caries (early childhood caries) · Preschool children (<6 years) · Case-control studies Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 1.04 [0.78, 1.38] | 5 studies · 1022 participants | Ungraded |
Gene sequencing (GS) applied to diagnose/manage oral conditions (predominantly 16S rRNA next-generation sequencing of the oral microbiome; also genome-wide/whole-genome sequencing) vs Negligible ('abysmal') effect of gene sequencing; no separate comparator arm (within-sample event contrast in the forest plots) Noticeable impact of gene sequencing on diagnosing/managing oral conditions · Human patients (any age) with oral-cavity related disorders (e.g. dental caries, periodontitis, gingivitis,… · Overall Gene sequencing applications to combat oral-cavity related disorders: a systematic review with meta-analysis. (2024) | RR 0.50 [0.46, 0.54] | 8 studies · 2211 participants | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study design: Case-control RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.40 [0.76, 2.59] | 4 studies | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study location: Africa RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 0.73 [0.27, 1.97] | 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) Overall diagnostic accuracy (agreement) · 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 accuracy; narrative synthesis) Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | Accuracy 92.9% to 97.6% | 5 studies | Ungraded |
Presence of oral Candida albicans vs Absence of oral Candida albicans Early childhood caries (ECC) · Children aged ≤6 years (early childhood) · Exposure and outcome assessed concurrently (observational); children aged ≤6 years, Overall (all 22 studies, random-effects) RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 4.42 [3.14, 6.24] | 22 studies · 3301 participants | Ungraded |
Breastfeeding for <24 months vs Breastfeeding for ≥24 months 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 0.59 [0.33, 1.05] | 4 studies · 2271 participants | 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 Child oral health behaviour · 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 | One trial (Shenoy 2022) reported changes in child oral health behaviours (other data): some benefit in favour of the intervention. | 1 study | Ungraded |
Presence of oral Candida albicans vs Absence of oral Candida albicans Early childhood caries (ECC) · Children aged ≤6 years (early childhood) · Exposure and outcome assessed concurrently (observational); children aged ≤6 years, Sample size: >=100 (Table 6; abstract text erroneously states '>=1000') RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 4.65 [2.57, 8.42] | 6 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 formation (reduction) · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | Cranberry extract/PAC reduced S. mutans biofilm formation: 51% at 500 ug/mL (Philip 2019), 95.2% at 50 mg/mL (Sumathi), 50-70% of preformed biofilm at 16.67-20.83 mg/dL (Singhal), 32%/29%/14% at 500/250/125 ug/mL… | 10 studies | Ungraded |
Silver diamine fluoride (SDF) vs Silver nitrate plus fluoride varnish Dental pain or sensitivity · Children and adults (with or without carious lesions) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies reported data for this outcome in this comparison | 0 studies | No studies |
Genome-wide common variants (additive dosage; present-study GWAS) vs Genome-wide significance threshold (P<5E-8) Periodontal disease - genome-wide-significant loci (present study) · Japanese adults (present-study cohort: 7,059 periodontal disease cases / 38,466 controls) · Lifelong (germline genotype), Present-study GWAS (Japanese) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | In the present Japanese GWAS, no loci reached genome-wide significance for periodontal disease; several loci reached the suggestive level (P<1E-5). Top-associated variant rs12624579 (SYNDIG1 intron). | 1 study · 45525 participants | Ungraded |
Started toothbrushing with fluoride toothpaste at or before 12 months (earlier start) vs Started after 12 months (later start) 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 0.83 [0.41, 1.67] | 1 study · 134 participants | Very low |
Grade level 1-4 (first cycle) vs Grade level 5 or above Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.46 [1.523, 3.397] | NR | Ungraded |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage G-H at extraction 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 2.75 [0.50, 15.10] | 3 studies | Ungraded |
Maternal smoking during pregnancy vs No maternal smoking during pregnancy Dental caries · Children · Overall Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.78 [1.55, 2.05] | 12 studies · 90405 participants | Ungraded |
Started toothbrushing with fluoride toothpaste before 4 years (earlier start) vs Started after 4 years (later start) 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 1.60 [0.77, 3.35] | 2 studies · 1484 participants | Very low |
Mouth-rinse probiotic vs No treatment or placebo (control) Salivary pH · Children and/or adolescents (<18 years) without background systemic disease · Probiotic presentation: mouth rinse (vs other presentations; p-interaction<0.01) Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024) | MD -0.40 [-0.54, -0.26] | NR | Ungraded |
High salivary S. mutans level vs Lower salivary S. mutans level Sites with attachment loss greater than 3 mm · Humans with salivary S. mutans measured · Overall Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 0.74 [0.35, 1.60] | 1 study | 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: European countries Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 0.81 [0.36, 1.81] | 3 studies | Ungraded |