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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 |
|---|---|---|---|
nCaF2 primer vs Control Transbond primer Enamel demineralization (DIAGNOdent score) · Patients undergoing fixed orthodontic treatment · 1, 3, and 6 months after bonding Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024) | Statistically significant scores in favor of the nCaF2 primer at T1, T3, and T6 (p-value = 0.000). | 1 study · 31 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Proportion of ancient skulls with at least one non-carious cervical lesion (NCCL) · Ancient/prehistoric human skulls (excavated/archaeological skeletal remains) · Overall (all included studies) Investigation of the presence of Non-carious cervical lesions (NCCLs) in ancient adult skulls: analyzing… (2024) | Proportion 0.014 [0.001, 0.027] | 6 studies · 805 participants | Ungraded |
C allele vs T allele Dental caries · Children (<18 years) with vs without dental caries · Allelic model (C vs T) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.33 [1.03, 1.71] | 3 studies · 1329 participants | Ungraded |
Remineralizing orthodontic adhesives vs Control orthodontic adhesives Enamel remineralization or anti-demineralization · Human teeth with early enamel lesions surrounding orthodontic brackets · 5 days to 6 months Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024) | no estimate extracted | 24 studies | Ungraded |
Extraction of the permanent first molar vs None (single-group prevalence) Spontaneous space closure · Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent… · 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) | Prevalence 48.1 [34.5, 62.0] | 11 studies · 1095 participants | Ungraded |
Periodontitis vs No periodontitis (periodontal health or gingivitis) Dental caries (prevalence) · Adults · Age 30-64 years Association between periodontitis and dental caries: a systematic review and meta-analysis. (2024) | OR 1.67 [1.37, 2.03] | 3 studies | Ungraded |
Surgically-anchored orthodontic treatment (miniplates) vs Untreated control (no treatment) 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 | SoF2: Perceived need for surgery in adulthood - Not measured. | 0 studies | No studies |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Study quality (NOS): Low RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 0.95 [0.39, 2.33] | 6 studies | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children aged <6 years · Confounder adjustment: No RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 0.98 [0.66, 1.47] | 15 studies | Ungraded |
Higher mean patient age (per 1 year) vs Lower mean patient age (per 1-year decrement) 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 0.59 [0.20, >100.00] | 3 studies | Ungraded |
Occlusal splint vs Pharmacological therapy Frequency of joint noise · People with temporomandibular disorders (TMD) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | Listed in Summary of findings 6 as 'Not reported'; this outcome was not reported by any included study for this comparison. | 0 studies | No studies |
Spirulina vs Oxitard (antioxidant) 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 -2.60 [-3.82, -1.38] | 1 study · 50 participants | Low |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Aesthetics · 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 |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Depression · People with temporomandibular disorders (TMD) · Short term, Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -0.25 [-0.52, 0.02] | 1 study · 60 participants | Ungraded |
CC+CT genotypes vs TT genotype Dental caries · Children (<18 years) with vs without dental caries · Dominant model (CC+CT vs TT) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.87 [1.15, 3.04] | 3 studies · 1329 participants | Ungraded |
Orthodontic removable traction appliance (ORTA) vs Untreated control (no treatment) Overjet · 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 6.20 [5.52, 6.88] | 1 study · 40 participants | Ungraded |
Cesarean section delivery vs Vaginal delivery Early childhood caries (ECC) · Children with average age >3 years · Average age: >3 years RETRACTED: The association between mode of childbirth delivery and early childhood caries: A comprehensive… (2024) | OR 1.24 [0.89, 1.71] | 14 studies | Ungraded |
Superelastic NiTi arch wire vs Thermoelastic 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 0.40 [-0.11, 0.91] | 1 study · 86 participants | Ungraded |
Used a pea-sized amount of fluoride toothpaste or less vs Used more than a pea-sized amount 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 0.92 [0.66, 1.28] | 3 studies · 2037 participants | Very low |
Intervention NR Veillonella spp. association with caries (qualitative) A systematic review of Streptococcus Mutans and Veillonellae species interactions in dental caries… (2024) | Veillonella spp. associated with caries; no quantitative estimate reported | 1 study | 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 24 hours · Adults with symptomatic apical periodontitis (no signs of spreading infection or systemic involvement) · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | The median pain at 24 hours in the control group was 3 (range 0 to 10); the median pain at 24 hours in the intervention group was the same (median 3, range 0 to 8). P = 0.219 (Mann-Whitney U). | 1 study · 72 participants | Low |
Occlusal splint vs Acupuncture Muscle pain when chewing · People with temporomandibular disorders (TMD) · Short term (1 month), Myofascial pain TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 0.10 [-0.80, 1.00] | 1 study · 40 participants | Very low |
Second molar distally inclined at extraction vs Second molar upright 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 1.18 [0.43, 3.21] | 3 studies | Ungraded |
Serum 25(OH)D < 50 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 2.00 [1.76, 2.28] | 6 studies · 4807 participants | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental caries experience (mean DMFT) · 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) | Mean DMFT (usually reported at population level) ranged from 0.26 to 16.6 across studies; the Missing component was typically highest and the Filled component lowest, reflecting limited access to dental care. | 12 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, Sample size: <=1000 Maternal smoking during pregnancy and early childhood dental caries in children: a systematic review and… (2024) | OR 1.63 [1.11, 2.40] | 3 studies | Ungraded |
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight) Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Age: 7-15 years Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.25 [0.87, 1.81] | 7 studies | Ungraded |
Lycopene plus intralesional betamethasone vs Placebo Severity of oral/mucosal burning pain/sensation · 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 | Kumar 2007 reported burning sensation using a non-validated scale; not included in quantitative analysis. | 1 study | Ungraded |
Buccal fat pad graft vs Extended nasolabial flap 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 -7.25 [-14.19, -0.31] | 1 study · 8 participants | Very low |
Single-strand superelastic NiTi arch wire vs Coaxial superelastic NiTi arch wire 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 |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental trauma prevalence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Urban vs rural; slum vs non-slum Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Dental trauma was more prevalent in urban than rural settings and among disadvantaged groups; Osuh 2022 reported 32% (slum) vs 21% (non-slum); Tobin & Ajayi 2017 found 87.5% of trauma cases in urban vs rural areas… | NR | Ungraded |
Non-surgical orthodontic treatment (any: facemask, chin cup, tandem traction bow, mandibular headgear, ORTA, reverse Twin Block, Reverse Forsus) vs 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 4.75 [4.15, 5.35] | 4 studies · 155 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 Swelling at 24 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 24 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | SMD 0.27 [-0.23, 0.78] | 2 studies · 62 participants | Very low |
Intervention NR Dental caries (early childhood caries) · Narrative single study (Lima 2016): no nocturnal BF vs nocturnal BF at 16 months Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 0.51 [0.39, 0.65] | 1 study | 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) · 3 to 6 months Interventions for managing oral submucous fibrosis (2024) · Cochrane | MD -0.57 [-2.34, 1.19] | 3 studies · 98 participants | Low |
Silver diamine fluoride (SDF) vs Sealants or resin infiltration Primary caries prevention · 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 reported data in this dentition type | 0 studies | No studies |
Surgery plus Heister jaw opener vs Surgery plus wooden tongue depressors 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 [0.01, 1.19] | 1 study · 50 participants | Very low |
Occlusal splint vs Another occlusal splint with a different mechanism of action Frequency of joint noise · People with temporomandibular disorders (TMD) · Short term (3 months), Disc displacement with reduction (DDwR) Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | RR 0.80 [0.07, 9.18] | 1 study · 9 participants | Very low |
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 collection: saliva RETRACTED: Investigating the association between Candida albicans and early childhood dental caries: A… (2024) | OR 4.70 [2.44, 9.09] | 7 studies | 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 Pain at 48 hours · Adults with a symptomatic necrotic tooth or localised acute apical abscess (no signs of spreading infection or… · 48 hours Systemic antibiotics for symptomatic apical periodontitis and acute apical abscess in adults (2024) · Cochrane | MD 0.32 [-0.22, 0.86] | 2 studies · 61 participants | 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 probing pocket depth (PPD) · 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 | MD 0.52 [0.31, 0.74] | 15 studies · 452 participants | Very low |
Occlusal splint vs Physical therapy (ultrasound, exercise, sensorimotor training, laser, TENS, manual therapy) Severity of joint noise · People with temporomandibular disorders (TMD) · Long term (4 months), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD 5.92 [0.18, 11.66] | 1 study · 20 participants | Very low |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints 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 0.70 [-0.60, 2.00] | 1 study · 42 participants | Ungraded |
Silver diamine fluoride (SDF) vs Placebo or no treatment Caries arrest · Children and adults (with or without carious lesions) · 24 months, Permanent dentition (root) Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane | MD 0.24 [0.12, 0.36] | 1 study · 158 participants | Very low |
AA genotype vs AG+GG genotypes Dental caries · Children (<18 years) with vs without dental caries · Recessive model (AA vs AG+GG) Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024) | OR 1.09 [0.70, 1.71] | 3 studies · 855 participants | Ungraded |
NiTi arch wire of one cross-sectional size vs NiTi arch wire of a different cross-sectional size Pain · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 7 days Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane | Different sizes of NiTi wires (Alhaija 2021; Erdinc 2004); not pooled due to clinical heterogeneity; little or no difference at day 1. Erdinc 0.014 vs 0.016 inch higher pain at day 4 MD 5.00 (0.19 to 9.81) and day 6 MD… | 2 studies · 149 participants | Low |
Teledentistry diagnosis using DSLR or smartphone extra-oral photographs vs Visual or clinical examination Negative predictive value 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 | 10 studies | Ungraded |
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 |
Occlusal splint vs Behavioural therapy (counselling, CBT, relaxation, self-care management) Joint pain at rest · People with temporomandibular disorders (TMD) · Short term (1 month), Mixed TMD Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane | MD -2.59 [-4.21, -0.97] | 1 study · 39 participants | Very low |
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 |