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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.

Limit to evidence status or GRADE (optional)

164 questions in 26 reviews · Oral medicine and oral cancer

current versions
No studies 164 · 100%Ungraded 0 · 0%Very low 0 · 0%Low 0 · 0%Moderate 0 · 0%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.

QuestionEffectEvidenceStatus / GRADE
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Hospital admission (length of stay) · 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
The trials did not measure hospital admission.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Participant-reported resumption of normal eating, chewing and speech · 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
SoF: participant-reported resumption of normal eating, chewing and speech - outcome not reported by included studies.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Postoperative discomfort or pain · 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
The trials did not measure postoperative discomfort or pain.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Participant satisfaction · 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
The trials did not measure participant satisfaction.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Improvement in range of jaw movement · 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
The trials did not measure range of jaw movement.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Quality of life · 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
The trials did not measure quality of life.0 studiesNo studies
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Direct costs · 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
The trials did not measure costs.0 studiesNo studies
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy)
Disease-free survival · Adults with oral cavity or oropharyngeal cancer · oral cavity
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Disease-free survival: not reported (Iyer 2015).0 studiesNo studies
Surgery plus radiotherapy vs Radiotherapy alone
Locoregional recurrence · Adults with oral cavity or oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Locoregional recurrence: not reported.0 studiesNo studies
Surgery plus radiotherapy vs Radiotherapy alone
Disease-free survival · Adults with oral cavity or oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Disease-free survival: not reported.0 studiesNo studies
Elective radical (comprehensive) neck dissection vs Elective selective neck dissection
Locoregional recurrence · Adults with oral cavity cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Locoregional recurrence: not reported.0 studiesNo studies
Surgery vs Radiotherapy alone
Locoregional recurrence · Adults with oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Locoregional recurrence: not reported.0 studiesNo studies
Surgery plus radiotherapy vs Radiotherapy alone
Recurrence · Adults with oral cavity or oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Recurrence: not reported.0 studiesNo studies
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 studiesNo studies
Superselective neck dissection vs Selective neck dissection
Total mortality · 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
Total mortality: not reported.0 studiesNo studies
Supraomohyoid neck dissection vs Modified radical neck dissection
Disease-free survival · Adults with oral cavity or oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Disease-free survival: not reported (Guo 2014 reported disease-specific survival, not a review outcome).0 studiesNo studies
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy)
Recurrence · Adults with oral cavity or oropharyngeal cancer · oral cavity
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Recurrence: not reported for the oral cancer subgroup (Iyer 2015).0 studiesNo studies
Surgery vs Radiotherapy alone
Recurrence · Adults with oropharyngeal cancer
Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane
Recurrence: not reported.0 studiesNo studies
Superselective neck dissection vs Selective neck dissection
Recurrence · 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
Recurrence: outcome not reported in a usable way in either study.0 studiesNo studies
Oral cytology (e.g. OralCDx brush biopsy, CytID) vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
Oral cytology (e.g. brush biopsy) was added to the list of eligible index tests in this update; no eligible studies evaluated it (evidence gap).0 studiesNo studies
COE with blood/salivary (biomarker) analysis vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
There were no eligible studies evaluating blood or salivary sample analysis (which tests for the presence of biomarkers for OPMD and OSCC).0 studiesNo studies
Chemotherapy (any regimen; added to, or compared with, locoregional treatment) vs Locoregional treatment and/or an alternative chemotherapy regimen
Quality of life · People receiving curative-intent treatment for oral cavity and oropharyngeal (squamous cell) cancer
Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy (2021) · Cochrane
Quality of life was a planned (protocol) outcome but no included trial provided usable quality-of-life data; the protocol was modified to report only survival/response outcomes.0 studiesNo studies
Chemotherapy vs Placebo
Outcome NR · People receiving curative-intent treatment for oral cavity and oropharyngeal (squamous cell) cancer
Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy (2021) · Cochrane
Types of studies: it was anticipated that there would be no studies comparing chemotherapy with placebo (none were identified).0 studiesNo studies
COE with light-based detection (e.g. ViziLite Plus, Microlux/DL, VELscope, Identafi 3000) vs COE with vital rinsing (toluidine blue/tolonium chloride)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible studies; planned comparative analysis (COE with vital rinse vs COE with light-based detection) not populated in this version.0 studiesNo studies
Blood and saliva analysis (biomarker tests) vs Surgical or punch biopsy with histological assessment
Outcome NR · Adults (aged 16 years or over) presenting to primary or secondary care with clinically evident suspicious or innocuous…
Diagnostic tests for oral cancer and potentially malignant disorders in patients presenting with clinically… (2021) · Cochrane
No eligible studies assessed the diagnostic test accuracy of blood and saliva analysis; potentially eligible biomarker studies were excluded as case-control designs.0 studiesNo studies
COE with blood/salivary (biomarker) analysis vs COE with vital rinsing (toluidine blue/tolonium chloride)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible studies; planned comparative analysis (COE with vital rinse vs COE with blood/salivary analysis) not populated in this version.0 studiesNo studies
COE with blood/salivary (biomarker) analysis vs Conventional oral examination (COE) alone
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible studies; planned comparative analysis (COE vs COE with blood/salivary analysis) not populated in this version.0 studiesNo studies
COE with light-based detection (e.g. ViziLite Plus, Microlux/DL, VELscope, Identafi 3000) vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
There were no eligible studies evaluating light-based detection.0 studiesNo studies
COE with light-based detection (e.g. ViziLite Plus, Microlux/DL, VELscope, Identafi 3000) vs Conventional oral examination (COE) alone
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible studies; planned comparative analysis (COE vs COE with light-based detection) not populated in this version.0 studiesNo studies
COE with vital rinsing (toluidine blue/tolonium chloride) vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible study evaluated COE with vital rinse as a stand-alone screen against the reference standard in this version.0 studiesNo studies
COE with blood/salivary (biomarker) analysis vs COE with light-based detection (e.g. ViziLite Plus, Microlux/DL, VELscope, Identafi 3000)
Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance…
Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane
No eligible studies; planned comparative analysis (COE with light-based detection vs COE with blood/salivary analysis) not populated in this version.0 studiesNo studies
Topical triamcinolone acetonide vs Topical tacrolimus
Pain resolution · People with symptomatic, biopsy-confirmed oral lichen planus (OLP); not concurrently receiving other OLP treatment · 3-8 weeks
Interventions for treating oral lichen planus: corticosteroid therapies (2020) · Cochrane
Summary of findings 2: 'No data for this outcome' (triamcinolone vs tacrolimus, pain resolution)0 studiesNo studies
Mechanical tongue cleaning (tongue scraper) vs No tongue cleaning
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 2 weeks
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
Mechanical tongue cleaning (tongue scraper) vs No tongue cleaning
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 2 weeks
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score assessed with patient's perception: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
0.3% triclosan + PVM/MA + sodium fluoride toothpaste vs Sodium fluoride (control) toothpaste
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 1 week
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
Hinokitiol gel vs Placebo gel
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 4 weeks
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
Chlorhexidine + zinc acetate mouthwash vs Placebo mouthwash
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 3 months
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
0.6% eucalyptus chewing gum vs Placebo chewing gum
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 4 weeks
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
1000 mg champignon extract vs Placebo
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 2 weeks
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
Mechanical tongue cleaning (tongue scraper) vs No tongue cleaning
Quality of life · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced…
Interventions for managing halitosis (2019) · Cochrane
Quality of life was a prespecified secondary outcome. None of the 44 included studies in the review (across all comparisons) reported quality-of-life data (review-wide evidence gap).0 studiesNo studies
Hinokitiol gel vs Placebo gel
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 4 weeks
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
Chlorhexidine + zinc acetate mouthwash vs Placebo mouthwash
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 3 months
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
1000 mg champignon extract vs Placebo
Dentist-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 2 weeks
Interventions for managing halitosis (2019) · Cochrane
Dentist-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for dentist-reported OLT score.0 studiesNo studies
Toothbrushing + 0.075% cetylpyridinium chloride mouthwash vs Toothbrushing
Patient-reported OLT score · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 3 weeks
Interventions for managing halitosis (2019) · Cochrane
Patient-reported OLT score: listed in the Summary of findings table but no data reported. No data were reported for patient-reported OLT score.0 studiesNo studies
0.6% eucalyptus chewing gum vs Placebo chewing gum
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 4 weeks
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
Toothbrushing + 0.075% cetylpyridinium chloride mouthwash vs Toothbrushing
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 3 weeks
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
0.3% triclosan + PVM/MA + sodium fluoride toothpaste vs Sodium fluoride (control) toothpaste
Adverse events · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · mean 1 week
Interventions for managing halitosis (2019) · Cochrane
Adverse events: listed in the Summary of findings table but no data reported. No data were reported for adverse events.0 studiesNo studies
Polaprezinc vs Azulene oral rinse
Salivary flow rate · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region
Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane
No data on salivary flow rates were reported.0 studiesNo studies
Polaprezinc vs Azulene oral rinse
Side effects · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region
Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane
No data on adverse events were reported.0 studiesNo studies
Keratinocyte growth factor (KGF; palifermin or repifermin), intravenous vs Placebo
Number of days unable to take medicine orally · Adults with cancer receiving treatment
Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane
No studies reported this outcome (planned secondary outcome not measured by any study in the review)0 studiesNo studies