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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 |
|---|---|---|---|
Oral cancer patients (cases) vs Healthy controls Clinical attachment loss (CAL) in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, CAL (clinical attachment loss) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 1.94 [0.22, 3.66] | 2 studies | Ungraded |
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 7 days · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 7 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | The median pain at 7 days in the control group was 0 (range 0 to 3); the median pain at 7 days in the intervention group was the same (median 0, range 0 to 1). P = 0.673 (Mann-Whitney U). | 1 study · 72 participants | Low |
Clearfil Protect Bond antibacterial fluoride-releasing primer vs Transbond XT conventional primer Bracket failure · Patients undergoing fixed orthodontic treatment · During orthodontic treatment Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | No statistically significant difference in bond failure rates was observed between quadrants bonded with Clearfil (CF) and those bonded with the conventional primer (p = 0.316). | 1 study · 35 participants | Ungraded |
Occlusal splint vs Another occlusal splint with a different mechanism of action Discomfort · 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 |
Intervention NR Dental caries (early childhood caries) · Narrative single study (Ganesh 2022): BF at beginning of sleep Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | AOR 6.7 | 1 study | Ungraded |
High-frequency sugar consumption (three or more times daily) vs Low sugar intake (fewer than three times daily) Dental caries experience (prevalence) · Nigerian individuals, including children and adults, with primary or permanent dentition · Overall (all dentitions pooled) A systematic review and meta-analysis of the association between sugar intake and dental caries in Nigeria. (2024) | OR 1.18 [0.87, 1.59] | 7 studies | Ungraded |
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) · GNI $20000-$39999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 30 [22, 38] | 11 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, Dental examination: Parent-reported dental caries Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.68 [1.35, 2.10] | 1 study | 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, Dental examination: Clinical oral examinations Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.82 [1.47, 2.26] | 2 studies | Ungraded |
Grape seed extract or grape seed flavonoid fractions vs No extract or vehicle control; other antimicrobial agents Bacterial adhesion · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 2 studies | Ungraded |
Prophylaxis (teeth cleaning) and CHX or iodine-NaF solution application in the dentition of women (mothers) vs Placebo Mother caries (dmfs increment) · 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 -0.21 [-2.22, 1.79] | 2 studies · 130 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 Endodontic flare-up · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 3 days Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | RR 0.27 [0.01, 4.90] | 1 study · 19 participants | Ungraded |
Low-power CO2 laser irradiation (LLLT, 0.5 to 2 W) vs Placebo / no laser (control) Incidence of new white spot lesions (WSLs) · High caries-risk patients: fixed-orthodontic-appliance patients and children with partially erupted permanent molars · 3 to 18 months follow-up Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | OR 0.21 [0.15, 0.30] | 3 studies · 182 participants | Ungraded |
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) · GNI <$5000 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 57 [47, 67] | 19 studies | Ungraded |
Intervention NR Overall success (composite of clinical and radiographic success) · Mixed root maturation (both mature and immature teeth) Efficacy of pulpotomy for permanent teeth with carious pulp exposure: A systematic review and meta-analysis… (2024) | Proportion 0.950 [0.859, 0.998] | 3 studies | Ungraded |
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi) Time to alignment · 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 | Time to alignment: not reported | 0 studies | No studies |
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination Specificity for dental caries diagnosis · 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 |
TiO2-modified composite (1 wt.%) vs Control composite in contralateral quadrant Enamel demineralization (DIAGNOdent score) · Patients undergoing fixed orthodontic treatment · 1 to 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Mean readings were significantly greater on the control side than on the experimental side (p < 0.001) at all time points except at baseline. | 1 study · 40 participants | Ungraded |
TT genotype vs TC+CC genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (TT vs TC+CC), Primary dentition 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 |
Adjunctive antimicrobial photodynamic therapy (aPDT) applied after submucosal instrumentation (SI) vs Submucosal instrumentation (SI) alone, or SI plus placebo/sham aPDT Change in bleeding on probing (BOP) · Adults (> 18 years) with peri-implant mucositis, receiving active treatment · 3 months (change from baseline) Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri‐implant diseases (2024) · Cochrane | MD 1.60 [0.27, 2.93] | 1 study · 38 participants | Ungraded |
CC+TT (homozygous) genotypes vs CT (heterozygous) genotype Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (CC+TT vs CT) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 0.83 [0.67, 1.04] | 3 studies · 1329 participants | Ungraded |
A allele vs G allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (A vs G) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.07 [0.70, 1.64] | 3 studies · 855 participants | Ungraded |
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration) Primary caries prevention · 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 | 0 studies | No studies |
Oxitard (antioxidant) vs Aloe vera gel Difficulty in swallowing (participant-reported proxy) · 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 | OR 0.17 [0.07, 0.44] | 1 study · 120 participants | 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) · Life expectancy: >80 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 1.34 | NR | Ungraded |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Participant satisfaction or quality of life · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -1.42 [-15.78, 12.94] | 2 studies · 73 participants | Ungraded |
Fluoride varnish applied before 4 years of age vs No fluoride varnish application 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 2.18 [1.46, 3.25] | 2 studies · 982 participants | Low |
Pentoxifylline vs Spirulina 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 -8.00 [-14.47, -1.53] | 1 study · 40 participants | Low |
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), Caucasian ethnicity Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.26 [0.88, 1.80] | NR | Ungraded |
Hydrocortisone plus hyaluronidase (intralesional) 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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -4.88 [-12.87, 3.11] | 1 study · 12 participants | Very low |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Moderate periodontitis Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.38 [1.15, 1.66] | 7 studies | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Mild periodontitis Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.65 [0.45, 6.05] | 1 study | Ungraded |
Occlusal splint vs No treatment or placebo (non-occlusal or transparent-foil placebo splint) Muscle pain at rest · People with temporomandibular disorders (TMD) · Short term (mean 2 months), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -11.63 [-29.37, 6.11] | 1 study · 37 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: Visual examination Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.85 [1.59, 2.16] | 4 studies | Ungraded |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.33 [-3.31, 2.65] | 1 study · 40 participants | Ungraded |
Multistrand stainless steel wire vs Wires of other materials (conventional stainless steel, superelastic NiTi, thermoelastic NiTi) 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 |
Occlusal splint vs Another occlusal splint with a different mechanism of action Muscle pain at rest · 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 |
Nd:YAG laser irradiation vs Untreated control enamel Enamel acid resistance (cross-sectional microhardness) · Human enamel in pits and fissures (in situ / ex vivo) Clinical and ex-vivo effect of LASERs on prevention of early-enamel caries: systematic review & meta-analyses. (2024) | Narrative only (not meta-analyzed). Correa-Afonso: Nd:YAG (and CO2) laser increased enamel acid resistance in pits and fissures; microhardness of the Nd:YAG group was higher than the control group. | 1 study | Ungraded |
High-dose vitamin D3 supplementation during pregnancy (2400 IU/day from pregnancy week 24 to 1 week postpartum, in addition to the recommended 400 IU/day) vs Low-dose (standard) vitamin D supplementation as recommended in national pregnancy guidelines 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 |
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 4 to 6 years whose mothers' prenatal vitamin D status was assessed · Prenatal exposure; dental caries at 4 to 6 years, Children's age subgroup: 4 to 6 years Association between prenatal vitamin D deficiency with dental caries in infants and children: a systematic… (2024) | OR 1.44 [1.32, 1.56] | 8 studies | Ungraded |
Intralesional triamcinolone vs Intralesional salvianolic acid B 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 -0.60 [-3.76, 2.56] | 1 study · 28 participants | Very low |
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents Antioxidant capacity · Streptococcus mutans cultures and biofilms Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024) | no estimate extracted | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Overall (all included studies) Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 35 [27, 43] | 7 studies · 3711 participants | Ungraded |
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration) 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 | 0 studies | No studies |
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Atraumatic restorative treatment / glass ionomer cement (ART/GIC) Caries arrestment at the tooth level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 6 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 1.22 [0.09, 16.34] | 2 studies · 273 participants | Ungraded |
Levamisole vs Antioxidant (Antoxid) Burning sensation (VAS 0-100) · 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 -9.10 [-16.23, -1.97] | 1 study · 30 participants | Very low |
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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -1.00 [-7.18, 5.18] | 1 study · 30 participants | Very low |
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 Swelling at 7 days · 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 0.02 [-0.28, 0.32] | 1 study · 41 participants | Very low |
Silver diamine fluoride (SDF) vs Atraumatic restorative treatment (ART) with glass ionomer cement (GIC) or glass ionomer material Aesthetics · Children and adults (with or without carious lesions) · 24 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | 1 study reported that 45% of parents were satisfied with appearance of their child's teeth; data not reported by study group. 1 study reported that 1 of 34 caregivers in SDF group were "annoyed with teeth appearance",… | 2 studies · 248 participants | Very low |
SDF (given at a particular frequency, concentration, or duration) vs SDF (given at a different frequency, concentration, or duration) Adverse effects · Children and adults (with or without carious lesions) · 24 to 30 months, Children Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | 1 study (203 children) reported that black or brown staining on treated lesions was commonly found in both groups, with little or no difference according to whether SDF treatment was given in 3 applications at… | 3 studies · 1121 participants | Very low |