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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.
420 questions in 100 reviews · cluster CL0279
current versionsNo studies 131 · 31.2%Ungraded 222 · 52.9%Very low 47 · 11.2%Low 16 · 3.8%Moderate 4 · 1%High 0 · 0%
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.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Brushed less than once per day vs Brushed once or more per day 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 0.62 [0.53, 0.74] | 2 studies · 1693 participants | Low |
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment Adverse effects · 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 | Adverse effects (any): 0 in placebo vs 2 minor (flatulence and bloating); 90 (1); no GRADE rating given. | 1 study · 90 participants | Ungraded |
Facemask with rapid maxillary expansion (RME) vs Pushing Splints Adverse effects · 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 | Galeotti 2021: occasional skin irritation on the chin and three appliance breakages (one facemask, two Pushing Splints). | 1 study · 42 participants | Ungraded |
Vasodilators (isoxsuprine, xanthinol nicotinate) vs Placebo or no active treatment Adverse effects · 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 | Adverse effects (any): 0 placebo vs 14 minor (transient flushing and upper trunk warmness); 85 (2); no GRADE rating. | 2 studies · 85 participants | Ungraded |
Bone-anchored intermaxillary traction (BAIMT) vs Removable mandibular retractor (RMR) Adverse effects / patient-reported (pain, self-confidence) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · During treatment Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | Majanni 2016: BAIMT associated with higher pain early in treatment than RMR (P<0.001); RMR negatively impacted self-confidence more than BAIMT at all time points (P<0.001). | 1 study · 38 participants | Ungraded |
Brushed less than twice per day vs Brushed twice or more per day 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 0.88 [0.71, 1.08] | 3 studies · 2037 participants | Very low |
Abdominal dermal fat graft vs Nasolabial flap Adverse effects · 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 | Kania 2022 reported 3/30 serious adverse effects (graft failure) requiring prolonged hospital stay in the abdominal dermal fat graft group; no GRADE rating. | 1 study · 30 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 Adverse effects · 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 | 1 participant reported diarrhoea (placebo group); 1 participant reported fatigue and reduced energy postoperatively (antibiotic group). 61 participants (2 studies). | 2 studies · 61 participants | Very low |
Facemask vs Untreated control (no treatment) Adverse effects (temporomandibular joint signs and symptoms) · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment / follow-up Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane | Mandall 2010: no statistical analysis of TMJ signs/symptoms due to low prevalence; at 6-year follow-up reported no adverse effects from facemask. | 1 study · 69 participants | Ungraded |
Intralesional dexamethasone injections vs Placebo injections Adverse effects · 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 | Adverse effects (any): no adverse effects reported; 25 (1); no GRADE rating. | 1 study · 25 participants | 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 Adverse effects · 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 | No adverse effects reported in the placebo group; 1 participant reported dizziness in the intervention group. 72 participants (1 study). | 1 study · 72 participants | Low |
Brushed less than twice per day vs Brushed twice or more per day 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 1.63 [0.81, 3.28] | 2 studies · 258 participants | Very low |
Part-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Adverse effects on oral health: Gingival Index (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | MD -0.34 [-0.66, -0.02] | 1 study · 59 participants | Very low |
Surgery vs Radiotherapy alone Adverse events associated with treatment · Adults with oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: grade 2+ treatment-related events similar (31/34 radiotherapy vs 33/34 surgery; RR 0.94, 0.83 to 1.06); more hearing loss/neutropenia/constipation/tinnitus with radiotherapy, more oral bleeding/trismus… | 1 study · 68 participants | Very low |
Hawley removable retainer vs Clear plastic removable retainer Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Elective neck dissection (at time of primary tumour resection) vs Therapeutic (delayed) neck dissection Adverse events associated with treatment · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | RR 1.31 [1.11, 1.54] | 2 studies · 746 participants | Moderate |
Biodentine vs Mineral trioxide aggregate (MTA) Tooth discoloration · Patients with carious pulp exposure in permanent teeth undergoing DPC or pulpotomy · ≥6 months follow-up Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious… (2023) | Tooth discoloration was recorded in 4 trials; the 3 Biodentine-vs-MTA trials consistently showed more discoloration with MTA (Awawdeh 2018: 27/35 MTA vs 0/34 BD; Parinyaprom 2018: 11/31 MTA vs 0/29 BD; Uesrichai 2019:… | 3 studies | Ungraded |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Harms and side effects: orthodontically-induced inflammatory root resorption (OIIRR), mm · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | MD 0.09 [-0.35, 0.53] | 1 study · 50 participants | Low |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 1 RCT at 6 months found no difference (very low-certainty) | 0 studies | No studies |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Harms: serious adverse effects · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | No serious adverse effects were reported across five studies that assessed harms (Katchooi 2018; Lombardo 2018; Pavlin 2015; Reiss 2020; Taha 2020). | 5 studies | Ungraded |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Adverse effects on oral health: Gingival Index (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | MD 0.00 [-0.16, 0.16] | 2 studies · 107 participants | Low |
Sentinel node biopsy (neck dissection only if biopsy positive) vs Elective neck dissection Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: no adverse events were reported (Garrel 2020). | 1 study · 279 participants | Very low |
Elective radical (comprehensive) neck dissection vs Elective selective neck dissection Adverse events associated with treatment · Adults with oral cavity cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events (BHNCSG 1998): flap necrosis, wound infection, fistula, vascular rupture, haematoma, seroma, chyle fistula; no complications in 45/76 modified radical ND and 54/72 supraomohyoid ND; 2 vs 1 postoperative… | 1 study · 148 participants | Low |
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy) Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: not reported for any participants (Iyer 2015). | 0 studies | No studies |
Superselective neck dissection vs Selective neck dissection Adverse events associated with treatment · Adults with oral cavity cancer (tongue or floor of mouth) and clinically negative neck nodes Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: no adverse events reported; 72 participants (2 RCTs). | 2 studies · 72 participants | Very low |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 2 RCTs at 6 months found no difference (low-certainty) | 0 studies | No studies |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Harms: non-serious adverse effects (headache, discomfort, loosening of temporary anchorage devices) · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | RR 0.96 [0.32, 2.85] | 1 study · 45 participants | Ungraded |
Supraomohyoid neck dissection vs Modified radical neck dissection Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: significant difference in complication rates, lower for supraomohyoid (SOND 13.0% vs MRND 21.9%, P=0.040). UW-QOL at 1 year: supraomohyoid superior in pain relief (78.8% vs 75.2%, P=0.013) and shoulder… | 1 study · 332 participants | Very low |
Full-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Adverse effects on oral health: gingival bleeding (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | RR 0.53 [0.31, 0.88] | 1 study · 84 participants | Very low |
Surgery plus radiotherapy vs Radiotherapy alone Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: severe acute effects in both groups (subcutaneous fibrosis, telangiectasia, moderate-to-severe oedema, xerostomia, trismus, dysphagia); subcutaneous fibrosis more prevalent with surgery + radiotherapy… | 1 study · 35 participants | Very low |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Adverse effects on oral health: Gingival Index (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 1 RCT at 6 months: higher gingival inflammation with fibre-reinforced composite (MD 0.59, 95% CI 0.13 to 1.05; very low-certainty) | 0 studies | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Harms and side effects arising during treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Harms and side effects | Not reported. None of the included studies assessed harms arising during the LED intervention. | NR | No studies |
PET-CT following chemoradiotherapy (neck dissection only if no/incomplete response) vs Planned neck dissection before or after chemoradiotherapy Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer with nodal disease (stage N2 or N3) Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: 22 surgical complications in the PET-CT group vs 83 in the planned-surgery group (Mehanna 2017). | 1 study · 564 participants | Very low |
Full-time clear plastic (removable) retainer vs Any type of fixed (bonded) retainer Adverse effects on oral health: caries (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | RD 0.00 [-0.05, 0.05] | 1 study · 84 participants | Very low |
Scaling and root planing (SRP) plus antibiotics (amoxicillin and metronidazole) vs Supragingival scaling (plus placebo) Adverse events due to periodontal therapy · People with periodontitis and metabolic syndrome (no CVD; primary prevention) · 12 months Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis (2022) · Cochrane | Peto OR 0.14 [0.00, 6.90] | 1 study · 165 participants | Very low |
Dental extraction protocol with plasma rich in growth factors (PRGF) inserted into the postextraction alveolus vs Standard dental extraction protocol without PRGF Rate of complications and side effects of the intervention · People with cancer treated with intravenous bisphosphonates undergoing dental extractions (at risk of MRONJ) · 24 to 60 months Interventions for managing medication‐related osteonecrosis of the jaw (2022) · Cochrane | No intraoperative complications were observed in either of the groups. | 1 study · 176 participants | Ungraded |
Hypnosis vs Relaxation Adverse events · People aged 12 years and over with painful TMD lasting 3 months or longer Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane | Abrahamsen 2011: one participant who received hypnosis was admitted to a psychiatric hospital during the intervention; per study authors this was unrelated to the study treatment. | 1 study | Ungraded |
Flowable resin composite vs Fluoride-releasing resin-based sealant Adverse events · Children who were regular dental attenders with caries-free first or second primary molars (public health service… Sealants for preventing dental caries in primary teeth (2022) · Cochrane | No studies reported this outcome. | 0 studies | No studies |
Delicate surgery and wound closure by primary intention vs Non-traumatic tooth avulsion and wound closure by secondary intention Rate of complications and side effects of the intervention · People treated with oral bisphosphonates undergoing dental extractions (at risk of MRONJ) Interventions for managing medication‐related osteonecrosis of the jaw (2022) · Cochrane | No intraoperative complications were observed in either of the two groups. | 1 study · 700 participants | Ungraded |
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo Mortality or serious adverse events requiring hospitalisation · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive… Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane | Mortality or serious adverse events requiring hospitalisation | No data reported | 248 (1 study) | - | - | 0 studies | No studies |
Relaxation vs Occlusal (oral) appliance Adverse events · People aged 12 years and over with painful TMD lasting 3 months or longer · Adolescents (12-19 years) Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane | Wahlund 2015: reported no adverse treatment effects from treatment with an occlusal appliance or with relaxation therapy. | 1 study | Ungraded |
Professional oral care vs Usual oral care Adverse effects of interventions · Residents of nursing homes and other long-term care facilities Oral care measures for preventing nursing home‐acquired pneumonia (2022) · Cochrane | Measured in only 1 study (834 participants), which reported no serious events and 64 non-serious events, the most common of which were oral cavity disturbances (not defined) and dental staining. | 1 study · 834 participants | Ungraded |
Periodontal treatment: scaling and root planing (SRP) plus advice vs Community care: advice only Adverse events due to periodontal therapy · People with cardiovascular disease and chronic periodontitis · 6 to 25 months Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis (2022) · Cochrane | Adverse events: because of variable follow-up (6 to 25 months) and almost 90% loss to follow-up by one year, results were not considered useful for analysis; uncertain whether adverse events are more likely with either… | 1 study · 303 participants | Ungraded |
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo Adverse effects of antibiotics · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive… Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane | Adverse effects of antibiotics | No data reported | 248 (1 study) | - | - | 0 studies | No studies |
Traditional screening (referral card given if the inspecting dentist judges the child needs to see a dentist) vs No screening Adverse events · School children (aged 4 to 15 years), primary and secondary schools in the UK and India School dental screening programmes for oral health (2022) · Cochrane | Adverse events: Not reported (Summary of findings 1). | 0 studies | No studies |
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care Adverse effects of treatment · People with diabetes mellitus (type 1 or type 2, mostly type 2) and periodontitis, at least 16 years of age · 3-4 months Treatment of periodontitis for glycaemic control in people with diabetes mellitus (2022) · Cochrane | SoF comment: insufficient evidence to determine whether SRP for glycaemic control is associated with any harms; most studies did not evaluate adverse effects. Where reported (e.g. D'Aiuto 2018) serious adverse events… | NR | Ungraded |
Platelet rich plasma vs Placebo or no treatment Adverse events · Adults (>18 years) having permanent tooth extraction (predominantly mandibular third molars) · Follow-up: median 7 days Local interventions for the management of alveolar osteitis (dry socket) (2022) · Cochrane | No adverse events were reported in these two trials. | 2 studies | Ungraded |
Intensive periodontal treatment (subgingival SRP with or without other periodontal treatment) vs Supra-gingival scaling Adverse events (participants with adverse events or withdrawals due to adverse events) · Adults (any age/sex) with chronic periodontitis (>=5 teeth remaining; PPD >4 mm), with or without hypertension Effect of periodontal treatments on blood pressure (2021) · Cochrane | SoF 2 (Adverse effects): 3 studies reported no adverse effects. 328 (3 studies); Moderate. | 3 studies · 328 participants | Moderate |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Any other adverse effects, such as gingival disease and demineralisation · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | The studies did not report adverse events. | 0 studies | No studies |