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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)

15,213 questions in 2,394 reviews

current versions
No studies 15,213 · 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
Sodium hypochlorite 5.25% vs Normal saline
Mean change in health-related quality of life or participant-expressed satisfaction with the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 5.25% vs Sodium hypochlorite 5.25% with hydrogen peroxide 3%
Change in periapical radiolucency (radiography or CBCT), up to 1 year after treatment · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 1% with chlorhexidine 2% final rinse vs Sodium hypochlorite 1% with normal saline final rinse
Proportion of participants with moderate to severe pain 72 hours to 14 days after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Chlorhexidine 0.2% vs Normal saline
Adverse effects · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Chlorhexidine 0.2% vs Normal saline
Change in periapical radiolucency (radiography or CBCT), up to 1 year after treatment · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Any topical or systemic intervention (topical/systemic steroids, ciclosporin, tacrolimus, retinoids, anti-malarials, biologics, phototherapy, surgery) vs Placebo, no treatment, another active intervention, or a different dose of the same intervention
Reduction in severity of flares · People of any age with erosive lichen planus affecting the oral, anogenital, and/or oesophageal regions
Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane
No studies reported this outcome.0 studiesNo studies
Topical thalidomide vs Another topical agent or placebo
Adverse effects of long‐term use of available topical agents · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
HAART regimen + topical treatment vs HAART regimen alone
Pain relief · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
Chlorhexidine 0.2% vs Normal saline
Proportion of participants with moderate to severe pain up to 6 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Arthrocentesis
Outcome NR · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria
Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane
No study evaluated arthrocentesis for TMJ OA, which should be explored in future trials (Research recommendations Table 1).0 studiesNo studies
Thalidomide (immunomodulator) vs Placebo or no treatment
Outcome NR · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and…
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
Authors' conclusions: 'this review did not find trials involving several of other systemic interventions used for RAS, for example thalidomide in the absence of any systemic condition, despite its limitations on…0 studiesNo studies
Sodium hypochlorite 5.25% vs Sodium hypochlorite 5.25% with hydrogen peroxide 3%
Proportion of participants or samples with positive bacterial growth culture, up to 72 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 5.25% with hydrogen peroxide 3% vs Normal saline
Change in periapical radiolucency (radiography or CBCT), up to 1 year after treatment · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 1.3% with MTAD final rinse vs Sodium hypochlorite 1.3% with normal saline final rinse
Proportion of participants with moderate to severe pain 72 hours to 14 days after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Iontophoretically applied corticosteroids
Outcome NR · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria
Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane
The review noted the noticeable absence of evidence for iontophoretically applied corticosteroids; no eligible RCT evaluated it (Discussion).0 studiesNo studies
Technique to increase peri-implant keratinised/attached mucosa vs No increase of keratinised/attached mucosa
Outcome NR · Patients receiving dental implants
Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane
No trial: whether the peri-implant keratinised/attached mucosa has to be increased (objective 3a) - no trial identified0 studiesNo studies
HAART regimen + topical treatment vs HAART regimen alone
Incidence and recurrence after healing of ulcers · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
Sodium hypochlorite 5.25% with EDTA 17% vs Sodium hypochlorite 1.3% with MTAD
Proportion of participants or samples with positive bacterial growth culture, up to 72 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
One suturing technique/material vs A different suturing technique/material
Outcome NR · Patients receiving dental implants
Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane
No trial: which suturing techniques/materials are most effective (objective 4) - no trial identified0 studiesNo studies
Sodium hypochlorite 5.25% with hydrogen peroxide 3% vs Normal saline
Proportion of participants or samples with positive bacterial growth culture, up to 72 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 1% with chlorhexidine 2% final rinse vs Sodium hypochlorite 1% with normal saline final rinse
Proportion of participants with moderate to severe pain up to 6 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
One soft tissue correction/augmentation technique vs A different soft tissue correction/augmentation technique
Outcome NR · Patients receiving dental implants
Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane
No trial: which soft tissue correction/augmentation technique is most effective (objective 2b) - no trial identified0 studiesNo studies
Hydrocortisone (systemic corticosteroid) vs Placebo or no treatment
Outcome NR · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and…
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
Table 1: 'Studies of these corticosteroids were not found or included in the review but are included here for completeness.' No trial of hydrocortisone for RAS was identified.0 studiesNo studies
Physiotherapy modalities (physiotherapy, short-wave diathermy, ultrasound)
Outcome NR · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria
Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane
The review noted the noticeable absence of evidence for physiotherapy, short-wave diathermy and ultrasound; no eligible RCT evaluated these (Discussion).0 studiesNo studies
Sodium hypochlorite 5% (also 2.5%) vs Sodium hypochlorite 1%
Mean change in health-related quality of life or participant-expressed satisfaction with the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Antiseptic mouthwash (e.g. chlorhexidine) vs Another topical agent or placebo
Adverse effects of long‐term use of available topical agents · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
Sodium hypochlorite (NaOCl), 2.5% to 5.25% vs Chlorhexidine, 0.2% to 2% (solution or gel)
Adverse effects · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 5.25% vs Normal saline
Adverse effects · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Topical thalidomide vs Another topical agent or placebo
Healing of ulceration · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
Chlorhexidine 0.2% vs Normal saline
Mean change in health-related quality of life or participant-expressed satisfaction with the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Open TMJ surgery (arthroplasty / total joint replacement)
Outcome NR · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria
Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane
No study evaluated open surgery for TMJ OA, which should be explored in future trials (Research recommendations Table 1; Discussion).0 studiesNo studies
Sodium hypochlorite (NaOCl), 2.5% to 5.25% vs Chlorhexidine, 0.2% to 2% (solution or gel)
Proportion of participants with moderate to severe pain 72 hours to 14 days after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Topical thalidomide vs Another topical agent or placebo
Duration to heal oral ulcerations after initiation of treatment · HIV‐infected adults (> 13 years of age, per CDC) with one or more painful intraoral aphthous ulcers
Topical treatments for HIV‐related oral ulcers (2012) · Cochrane
No studies were included in this review. A total of 233 abstracts were retrieved; 25 were selected as potentially eligible but all were excluded (10 reported systemic rather than topical treatment; 3 non‐RCTs; 6…0 studiesNo studies
Sodium hypochlorite 5.25% vs Normal saline
Proportion of participants with new or worsening signs/symptoms of inflammation requiring a revisit, up to 14 days after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 1% with chlorhexidine 2% final rinse vs Sodium hypochlorite 1% with normal saline final rinse
Mean change in health-related quality of life or participant-expressed satisfaction with the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 5% vs Sodium hypochlorite 5% with proteolytic enzyme
Mean change in health-related quality of life or participant-expressed satisfaction with the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite (NaOCl), 2.5% to 5.25% vs Chlorhexidine, 0.2% to 2% (solution or gel)
Change in periapical radiolucency (radiography or CBCT), up to 1 year after treatment · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 5% (also 2.5%) vs Sodium hypochlorite 1%
Proportion of participants with moderate to severe pain up to 6 hours after the procedure · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Sodium hypochlorite 1.3% with MTAD final rinse vs Sodium hypochlorite 1.3% with normal saline final rinse
Change in periapical radiolucency (radiography or CBCT), up to 1 year after treatment · Patients aged 14 to 78 years with mature permanent teeth (fully formed roots), single or multi-rooted, with pulpal or…
Irrigants for non‐surgical root canal treatment in mature permanent teeth (2012) · Cochrane
no estimate extracted0 studiesNo studies
Secondary alveolar bone grafting performed at one timing (e.g. early secondary grafting) vs Secondary alveolar bone grafting performed at a different / optimal timing (e.g. late secondary grafting)
Outcome NR · Patients greater than 5 years of age with unilateral or bilateral cleft lip and/or palate involving the alveolar…
Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate (2011) · Cochrane
Furthermore, no RCTs were found to study the optimal timing ... with secondary bone grafting surgery. This systematic review has not been able to report all the objectives described in the protocol.0 studiesNo studies
Maternal advice and support (feeding techniques/breastfeeding positions) vs Usual care (no additional advice/support)
Outcome NR · Infants up to 6 months (from term) born with cleft lip, cleft palate or cleft lip and palate (Pierre Robin sequence or…
Feeding interventions for growth and development in infants with cleft lip, cleft palate or cleft lip and… (2011) · Cochrane
No trials were identified that examined the effect of additional maternal support or advice during breastfeeding (or bottle-feeding); no studies evaluated the effectiveness of this intervention (plain-language summary…0 studiesNo studies
Secondary alveolar bone grafting with a given sequence of orthodontic treatment (e.g. orthodontics before grafting) vs Secondary alveolar bone grafting with a different sequence of orthodontic treatment (e.g. orthodontics after grafting)
Outcome NR · Patients greater than 5 years of age with unilateral or bilateral cleft lip and/or palate involving the alveolar…
Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate (2011) · Cochrane
No RCTs were found to study ... the sequence of orthodontic treatment with secondary bone grafting surgery.0 studiesNo studies
Fluoride supplements (tablets, drops, lozenges or chewing gums) vs Topical fluoride (fluoride rinse, varnish or toothpaste)
Fluorosis (adverse effect; % of children with fluorotic teeth) · Children and adolescents (aged 16 years or less at baseline)
Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing dental caries in children (2011) · Cochrane
Summary of findings 2 lists fluorosis (% of children with fluorotic teeth) as 'See comment / Not estimable / Not estimated'; no included study reported fluorosis for the fluoride supplements versus topical fluoride…NRNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Economic and resource cost of flossing · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not reported. No included study measured the economic or resource cost of flossing; the review notes it may be important to measure in future trials.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Interproximal caries · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). See comment: No included study assessed caries as an outcome.0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Clinical attachment loss · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not estimable (0 studies). SoF comment reads (verbatim) 'No included study assessed calculus as an outcome' (apparent copy-paste typo in the clinical attachment loss row; no study assessed clinical attachment loss).0 studiesNo studies
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Bad breath (halitosis) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
Not reported. No included study measured halitosis; the review notes it may be important to measure in future trials.0 studiesNo studies
Intervention NR
Process of care · health professionals
Teaching critical appraisal skills in healthcare settings (2011) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Patient‐related outcomes · health professionals
Teaching critical appraisal skills in healthcare settings (2011) · Cochrane
no estimate extractedNRNo studies
Summary of findings: oral steroids plus antibiotic vs control plus antibiotic
OME resolution at long‐term · Children with otitis media with effusion
Oral or topical nasal steroids for hearing loss associated with otitis media with effusion in children (2011) · Cochrane
no estimate extractedNRNo studies