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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 |
|---|---|---|---|
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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Outcome NR · Adults (> 18 years) with peri-implantitis, receiving active treatment Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | Planned comparison; no studies met the inclusion criteria. The review found only one study of peri-implant disease (peri-implant mucositis, active treatment) and no studies including people with peri-implantitis… | NR | No studies |
Levamisole vs Antioxidant (Antoxid) 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 -1.00 [-7.18, 5.18] | 1 study · 30 participants | Very low |
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 |
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 Change in bleeding on probing (BOP) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 4.98 [-2.51, 12.46] | 3 studies · 127 participants | Very low |
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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -70.82 [-94.39, -47.25] | 2 studies · 500 participants | Moderate |
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 |
Facemask after Alt-RAMEC vs Facemask started simultaneously with Alt-RAMEC 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 0.40 [-0.42, 1.22] | 1 study · 30 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 |
Intralesional steroid injections vs Alternative medicinal treatments 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 [-2.16, 0.89] | 4 studies · 128 participants | Low |
Single preoperative dose of systemic antibiotics (clindamycin 600 mg), total chemo-mechanical debridement and root filling vs Matched placebo, total chemo-mechanical debridement and root filling Pain at 48 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | Median pain at 48 hours 1 (range 0 to 9) in the antibiotic group versus 2 (range 0 to 10) in the control group. P = 0.242 (Mann-Whitney U). | 1 study · 72 participants | Ungraded |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or 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) · More than 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -1.41 [-5.74, 2.92] | 1 study · 90 participants | Low |
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 |
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 Change in gingival recession (REC) · Adults (> 18 years) with recurrent periodontitis, receiving supportive (maintenance) periodontal care · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD -0.20 [-0.48, 0.08] | 1 study · 24 participants | Very low |
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 |
Facemask after Alt-RAMEC vs Facemask started simultaneously with 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 0.51 [-0.69, 1.71] | 1 study · 30 participants | Ungraded |
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 |
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 Percussion pain at 72 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 72 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.05 [-0.55, 0.65] | 1 study · 41 participants | Ungraded |
Occlusal splint vs Pharmacological therapy Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term, Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.95 [-6.87, 0.97] | 1 study · 40 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 |
Surgically-anchored orthodontic treatment (miniplates) vs Untreated control (no treatment) 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 5.20 [4.48, 5.92] | 1 study · 30 participants | Low |
Breastfeeding promotion and support (e.g. individually tailored home-based peer counselling on the importance of breastfeeding, with advice and support for healthy breastfeeding) vs Standard care dmfs index score · For interventions, pregnant and lactating women; for outcomes, children up to 6 years of age 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 |
Spirulina 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) Interventions for managing oral submucous fibrosis (2024) · Cochrane | Patil 2015b (spirulina vs topical aloe vera gel): reported important outcomes but data not in a usable format; excluded from meta-analysis. | 1 study | Ungraded |
Occlusal splint vs Acupuncture Self-reported joint pain when chewing · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 5 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 or no treatment Secondary prevention of caries · Children and adults (with or without carious lesions) · Permanent dentition (root) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | No studies measured this outcome for root surfaces | 0 studies | No studies |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Nano-silver fluoride (NSF; with or without green tea extract) Caries arrestment at the surface level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 12 to 18 months, SDF vs NSF The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024) | OR 0.52 [0.43, 0.63] | 1 study · 1853 participants | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Full pulpotomy, immature teeth Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.844 [0.748, 0.921] | 7 studies | Ungraded |
Cranberry extract / juice and proanthocyanidin (flavonoid) fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride) pH drop / acidogenicity buffering · Streptococcus mutans (in vitro cultures and biofilms) Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | Cranberry PAC buffered acidogenesis: final pH 5.6 vs 5.2 control (Koo), lactic acid reduced 44% (Philip 2019) and 46% at 500 ug/mL (Philip 2019 EJOS), final pH 4.7-4.9 vs 3.7 control (Duarte), and disrupted glycolytic… | 5 studies | Ungraded |
Silver diamine fluoride (SDF) vs Placebo or no treatment Secondary prevention of caries · Children and adults (with or without carious lesions) · 24 months, Permanent dentition (coronal) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | Peto OR 44.22 [33.12, 59.04] | 1 study · 663 participants | Very low |
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 Pocket closure · Adults (> 18 years) with a clinical diagnosis of periodontitis, receiving active (non-surgical anti-infective) treatment · 6 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | No studies measured this outcome at 6 months (SoF row labeled 'Change in pocket depth from baseline to 6 months after initial treatment'). | NR | No studies |
Silver diamine fluoride (SDF) vs Fluoride varnish Dental pain or sensitivity · Children and adults (with or without carious lesions) · 12 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | OR 0.36 [0.10, 1.34] | 1 study · 62 participants | Very low |
Intervention NR Correlation between teledentistry and clinical caries assessment · Studies reporting Spearman correlation (Almosa 2014, Daniel 2017, Zotti 2022) Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024) | Spearman correlation coefficient 0.76 to 0.99 (Almosa 0.76; Zotti 0.816; Daniel 0.99) | 3 studies | 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 0.89 [0.52, 1.52] | 2 studies · 258 participants | Very low |
High intake of sweets vs Lower/less intake of sweets Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.71 [1.968, 3.451] | 5 studies | Ungraded |