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Search review questions
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 |
|---|---|---|---|
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 |