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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.
149 questions in 24 reviews · cluster CL0141
current versionsNo studies 32 · 21.5%Ungraded 89 · 59.7%Very low 19 · 12.8%Low 5 · 3.4%Moderate 2 · 1.3%High 2 · 1.3%
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 |
|---|---|---|---|
Herbal mouthwash vs Placebo Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PI was significantly reduced compared to placebo [56]; VPI was significantly reduced compared to placebo [41]; PI was insignificantly reduced compared to placebo [19]. | 3 studies | Low |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Placebo mouthwash Pocket probing depth (PD) · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · <=3 months (short-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PD was significantly reduced except mid-lingual site compared to placebo [32]. The changes of PD were significantly higher compared to placebo [56]. | 2 studies | Low |
Cetylpyridinium chloride (CPC) mouthwash vs Blank control (no mouthwash; before-after comparison) Plaque-related index · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · <=3 months (short-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | BBPI was significantly reduced compared to blank control [47]. PI was significantly reduced compared to blank control [50]. The amount of dental plaque was significantly reduced compared to baseline [38]. | 3 studies | Very low |
Fluoride mouthwash vs Blank control Plaque-related index · Orthodontic patients · ≥ 12 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PI was similar to blank control [37]; API was slightly reduced compared to blank control and significant at 6 and 9 months [59]. | 2 studies | Very low |
Fluoride mouthwash (e.g., NaF / amine fluoride) vs Blank control (no mouthwash; before-after comparison) Cariogenic bacteria (Lactobacilli colony count) · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · >=12 months (long-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of LB was similar to blank control according to two studies [37, 59]. | 2 studies | Very low |
Fluoride mouthwash vs Blank control Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | TI was significantly reduced compared to baseline [34]; PI was significantly reduced compared to baseline but similar to blank control [46]. | 2 studies | Very low |
Herbal mouthwash vs Blank control Plaque-related index · Orthodontic patients · ≤ 3 months The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | PI was significantly reduced compared to baseline [39; 48; 54; 58]; BBPI was significantly reduced compared to blank control [47]; TI and dental plaque amount were significantly reduced compared to baseline [45; 38]. | 8 studies | Very low |
Chlorhexidine (CHX) mouthwash (adjunct to mechanical cleaning) vs Blank control (no mouthwash; before-after comparison) Total bacteria (colony count) · Orthodontic patients (any age) undergoing orthodontic treatment (mostly fixed appliances) · <=3 months (short-term) The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic… (2023) | Colony count of total bacteria were significantly reduced compared to placebos according to two studies [34, 43]. | 2 studies | Very low |
Essential oil mouthwash C (Listerine) vs Coloured and flavoured 5% hydroalcohol mouthwash Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · operator level; aerobic culture (cross-over; graph-only, not analysed) Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | One study (Fine 1993a) compared essential oil mouthwash C (Listerine) with coloured and flavoured 5% hydroalcohol mouthwash in a cross-over design for reduction in contamination by particles >5 um at operator level… | 1 study | Ungraded |
Any preprocedural mouth rinse vs Placebo, no rinsing or control Incidence of infection of dental healthcare providers · Dental patients undergoing aerosol-generating procedures (AGPs) Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | Primary outcome. Not measured by any of the 17 included studies (SoF tables state 'Not reported'); remained a total evidence gap from the protocol. | 0 studies | No studies |
Essential oil/herbal mouthwash vs Water Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · patient level (pharynx; not analysed) Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | Bay 1993 compared essential oil mouthwash C (Listerine) with distilled water and reported combined CFUs at different levels using Andersen's air sampler; level 2 (pharynx) was considered patient level and was not… | 1 study | Ungraded |
Any preprocedural mouth rinse vs Placebo, no rinsing or control Change of microbiota in the patient's mouth · Dental patients undergoing aerosol-generating procedures (AGPs) Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | No included study reported change of oral microbiota. | 0 studies | No studies |
Essential oil/herbal mouthwash vs Water Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · operator level Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | At operator level, because of high heterogeneity (I2 = 98%), the results were not meta-analysed (3 studies; Gupta 2014, Nayak 2020, Shetty 2013). No pooled estimate or GRADE rating. | 3 studies | Ungraded |
Essential oil/herbal mouthwash vs Water Reduction in level of contamination by particles >5 um (droplets) at <2 m from patient's oral cavity · Dental patients undergoing aerosol-generating procedures (AGPs) and the dental healthcare providers treating them · assistant level Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | At assistant level, because of high heterogeneity (I2 = 99%), the results were not meta-analysed (3 studies; Gupta 2014, Nayak 2020, Shetty 2013). No pooled estimate or GRADE rating. | 3 studies | Ungraded |
Herbal mouthrinse vs Chlorhexidine 0.2% mouthrinse Presence of dry socket · 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 | RR 0.50 [0.05, 5.17] | 1 study · 50 participants | Ungraded |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to healthcare workers, with or without the same intervention given to the patients with COVID-19 vs No treatment or saline or water Anosmia (or disturbance in sense of smell) · Healthcare workers (HCWs) treating patients with suspected or confirmed COVID-19 infection · Minimum 2 weeks Use of antimicrobial mouthwashes (gargling) and nasal sprays by healthcare workers to protect them when… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Incidence of VAP · Critically ill patients (adults and children) receiving mechanical ventilation in ICU · Follow-up: mean 1 month Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | RR 0.67 [0.47, 0.97] | 13 studies · 1206 participants | Moderate |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to healthcare workers, with or without the same intervention given to the patients with COVID-19 vs No treatment or saline or water Viral content of aerosol · Healthcare workers (HCWs) treating patients with suspected or confirmed COVID-19 infection Use of antimicrobial mouthwashes (gargling) and nasal sprays by healthcare workers to protect them when… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Caregivers' preferences for oral hygiene care · Critically ill patients (adults and children) receiving mechanical ventilation in ICU Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | The outcome of caregivers' preferences was not reported by any study in this comparison. | 0 studies | No studies |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Mortality · Critically ill patients (adults and children) receiving mechanical ventilation in ICU · Follow-up: mean 1 month Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | RR 1.03 [0.80, 1.33] | 9 studies · 944 participants | Moderate |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water COVID-19 viral content of aerosol (when present) · Patients with suspected or confirmed COVID-19 infection Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Dexamethasone mouthwash plus nystatin vs Photodynamic therapy Clinical resolution · People with symptomatic, biopsy-confirmed oral lichen planus (OLP); not concurrently receiving other OLP treatment Interventions for treating oral lichen planus: corticosteroid therapies (2020) · Cochrane | Bakhtiari 2017 (dexamethasone mouthwash + nystatin vs photodynamic therapy): clinical resolution reported (Analysis 4.6); no clear difference (low to very low certainty collectively) | 1 study | Ungraded |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to the patient or HCW before and/or after an AGP vs No treatment or saline or water Change in COVID-19 viral load at site(s) of irrigation · Patients without suspected or confirmed COVID-19 infection undergoing aerosol-generating procedures (AGPs), and the… Antimicrobial mouthwashes (gargling) and nasal sprays to protect healthcare workers when undertaking… (2020) · Cochrane | No data available (no included studies) | NR | No studies |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to the patient or HCW before and/or after an AGP vs No treatment or saline or water Anosmia (or disturbance in sense of smell) · Patients without suspected or confirmed COVID-19 infection undergoing aerosol-generating procedures (AGPs), and the… · Assessed at a minimum of 2 weeks Antimicrobial mouthwashes (gargling) and nasal sprays to protect healthcare workers when undertaking… (2020) · Cochrane | No data available (no included studies) | NR | No studies |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to the patient or HCW before and/or after an AGP vs No treatment or saline or water Incidence of symptomatic or test-positive COVID-19 infection in HCWs or patients · Patients without suspected or confirmed COVID-19 infection undergoing aerosol-generating procedures (AGPs), and the… · Assessed at a minimum of 2 weeks Antimicrobial mouthwashes (gargling) and nasal sprays to protect healthcare workers when undertaking… (2020) · Cochrane | No data available (no included studies) | NR | No studies |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to healthcare workers, with or without the same intervention given to the patients with COVID-19 vs No treatment or saline or water Changes in microbiome in oral cavity, nasal cavity, oro- or nasopharynx · Healthcare workers (HCWs) treating patients with suspected or confirmed COVID-19 infection Use of antimicrobial mouthwashes (gargling) and nasal sprays by healthcare workers to protect them when… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water Incidence of symptomatic or test-positive COVID-19 infection in healthcare workers · Patients with suspected or confirmed COVID-19 infection · Minimum 2 weeks Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to healthcare workers, with or without the same intervention given to the patients with COVID-19 vs No treatment or saline or water Incidence of symptomatic or test-positive COVID-19 infection in HCWs · Healthcare workers (HCWs) treating patients with suspected or confirmed COVID-19 infection · Minimum 2 weeks Use of antimicrobial mouthwashes (gargling) and nasal sprays by healthcare workers to protect them when… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water Anosmia (or disturbance in sense of smell) · Patients with suspected or confirmed COVID-19 infection · Minimum 2 weeks Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Duration of mechanical ventilation · Critically ill patients (adults and children) receiving mechanical ventilation in ICU · Follow-up: mean 1 month Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | MD -1.10 [-3.20, 1.00] | 4 studies · 594 participants | Very low |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Duration of ICU stay · Critically ill patients (adults and children) receiving mechanical ventilation in ICU · Follow-up: mean 1 month Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | MD -0.89 [-3.59, 1.82] | 5 studies · 627 participants | Low |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water Change in COVID-19 viral load in patients · Patients with suspected or confirmed COVID-19 infection Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water RECOVERY trial outcomes (mortality; hospitalisation status; use of ventilation; use of renal dialysis or haemofiltration) · Patients with suspected or confirmed COVID-19 infection · Minimum 2 weeks Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Chlorhexidine (mouthrinse or gel), as part of oral hygiene care vs Placebo or usual care Duration of systemic antibiotic use · Critically ill patients (adults and children) receiving mechanical ventilation in ICU Oral hygiene care for critically ill patients to prevent ventilator‐associated pneumonia (2020) · Cochrane | MD 0.65 [-0.58, 1.88] | 1 study · 146 participants | Ungraded |
Antimicrobial mouthwash and/or nasal spray (alone or in combination), any concentration, frequency or dosage vs No treatment, saline, or water Changes in microbiome in oral cavity, nasal cavity, oro- or nasopharynx · Patients with suspected or confirmed COVID-19 infection Antimicrobial mouthwashes (gargling) and nasal sprays administered to patients with suspected or confirmed… (2020) · Cochrane | No data available (no included studies) | 0 studies | No studies |
Any antimicrobial mouthwash and/or nasal spray (alone or in combination), at any concentration, delivered to the patient or HCW before and/or after an AGP vs No treatment or saline or water COVID-19 viral content of aerosol · Patients without suspected or confirmed COVID-19 infection undergoing aerosol-generating procedures (AGPs), and the… Antimicrobial mouthwashes (gargling) and nasal sprays to protect healthcare workers when undertaking… (2020) · Cochrane | No data available (no included studies) | NR | No studies |
0.1% chlorine dioxide mouthwash vs Placebo mouthwash Dentist-reported organoleptic test (OLT) score (scale 0 to 5) · 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 | MD -0.61 [-0.73, -0.49] | 1 study · 47 participants | Low |
Green tea mouthwash vs Placebo mouthwash Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 28 days Interventions for managing halitosis (2019) · Cochrane | MD -57.39 [-184.63, 69.85] | 1 study · 60 participants | Ungraded |
Lemongrass oil mouthwash vs Placebo mouthwash Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 8 days Interventions for managing halitosis (2019) · Cochrane | MD -26.66 [-43.39, -9.93] | 1 study · 20 participants | Ungraded |
Toothbrushing + 0.075% cetylpyridinium chloride mouthwash vs Toothbrushing Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 3 weeks Interventions for managing halitosis (2019) · Cochrane | MD -8.04 [-15.87, -0.21] | 1 study · 70 participants | Ungraded |
Chlorine dioxide mouthrinse (with tongue scraping) vs Chlorhexidine mouthwash (with tongue scraping) VSC: third component · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 1 week Interventions for managing halitosis (2019) · Cochrane | MD 22.8 [-33.18, 78.78] | 1 study · 22 participants | Ungraded |
Salvadora persica (miswak) mouthrinse vs Chlorhexidine mouthrinse Post-intervention mean plaque score · Medically healthy individuals (adults and children, 6-60 years) · Post-intervention, Did not refrain from mechanical plaque control The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… (2019) | MD 0.17 [-0.08, 0.42] | 11 studies · 594 participants | Ungraded |
Chlorine dioxide mouthrinse (with tongue scraping) vs Chlorhexidine mouthwash (with tongue scraping) VSC: methyl mercaptan · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 1 week Interventions for managing halitosis (2019) · Cochrane | MD 7.63 [-1.7, 16.96] | 1 study · 22 participants | Ungraded |
Salvadora persica (miswak) mouthrinse vs Chlorhexidine mouthrinse Post-intervention mean plaque score · Medically healthy individuals (adults and children, 6-60 years) · Post-intervention, Duration of mouthwash use: >=3 weeks The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… (2019) | MD 0.24 [-0.11, 0.60] | 7 studies · 420 participants | Ungraded |
Essential oil mouthwash vs Placebo mouthwash Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 2 weeks Interventions for managing halitosis (2019) · Cochrane | MD -5.13 [-32.94, 22.68] | 1 study · 45 participants | Ungraded |
Cetylpyridinium chloride mouthwash vs Placebo mouthwash Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 2 weeks Interventions for managing halitosis (2019) · Cochrane | MD -20.04 [-37.71, -2.37] | 1 study · 47 participants | Ungraded |
Chlorine dioxide + zinc mouthwash vs Placebo mouthwash Dentist-reported organoleptic test (OLT) score (scale 0 to 5) · 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 | MD -0.17 [-0.59, 0.25] | 1 study · 41 participants | Very low |
Benzethonium chloride mouthwash vs Placebo mouthwash VSC: methyl mercaptan · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 9 days Interventions for managing halitosis (2019) · Cochrane | MD 7.2 [-24.92, 39.32] | 1 study · 20 participants | Ungraded |
Salvadora persica (miswak) mouthrinse vs Chlorhexidine mouthrinse Post-intervention mean plaque score · Medically healthy individuals (adults and children, 6-60 years) · Post-intervention The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… (2019) | MD 0.19 [0.01, 0.37] | 18 studies · 902 participants | Ungraded |
Halita mouthwash (chlorhexidine 0.05% + cetylpyridinium chloride 0.05% + zinc lactate 0.14%) vs Placebo mouthwash Volatile sulphur compounds (VSC), halimeter · Adolescents and adults aged over 16 years with clinical or self-assessed halitosis of oral origin; excluding induced… · 2 weeks Interventions for managing halitosis (2019) · Cochrane | MD -188.0 [-308.29, -67.71] | 1 study · 40 participants | Ungraded |