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Search review questions

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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.

Limit to evidence status or GRADE (optional)

75,239 questions in 5,342 reviews

current versions
No studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%

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
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
Radix tripterygium hypoglaucum tablet (THT) vs Tripterygium glucosides tablet (TGT)
Physician Global Assessment (cure of erosive lesions, remarkably effective) · People with erosive oral lichen planus · Grade I (erosive and ulcerative lesions)
Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane
RR 0.55 [0.25, 1.20]1 study · 94 participantsUngraded
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
Extraction of the primary maxillary canine vs Untreated control (no treatment)
Change in the sagittal position of the upper first molars · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention
Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane
Change in the sagittal position of the upper first molars (Baccetti 2008 only): average sagittal displacement was 2.65 mm in the extraction-only group and 2.32 mm in the untreated control group (0.24 mm in the…1 studyUngraded
Prednisone (oral, commencing 25 mg with phased dose reduction over 2 months) vs Montelukast (leukotriene receptor antagonist)
Total number of new lesions over 2-month treatment period · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 2 months
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
MD -0.30 [-0.90, 0.30]1 study · 40 participantsUngraded
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
Extraction of the primary maxillary canine vs Untreated control (no treatment)
Prevalence of eruption/non-eruption of the palatally displaced permanent canine (successful eruption) · Children with palatally displaced maxillary canines (at least 80% aged 10 to 13 years); trials with craniofacial… · At least 6 months follow-up after the intervention
Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children (2012) · Cochrane
Narrative summary (data not poolable, not GRADE-rated). Leonardi 2004: successful eruption of the permanent canine 50% in the extraction-only group, which was not significantly greater than the success rate in…2 studies · 70 participantsUngraded
Colchicine (0.5 mg three times per day) vs Placebo
Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 6 months
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
There was a greater percentage of treatment interruptions in the colchicine group due to gastrointestinal adverse effects (Fisher's exact test P=0.009). The review noted potential evidence of harm at a dose of 1.5 mg…1 study · 43 participantsUngraded
Altered-cast technique RDP vs One-piece cast RDP
Patients with increased abutment tooth mobility · Partially edentulous patients treated with a distal-extension RDP
Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane
RR 1.81 [0.91, 3.58]1 study · 57 participantsUngraded
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
Camel thorn (plant distillate) vs Placebo
Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · up to 14 days
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
No evidence of drug side effects was observed.1 study · 93 participantsUngraded
LongoVital (herbal plus vitamin component) vs LongoVital (herbal component alone)
Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 4 months
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
Reported adverse events were minor and evenly distributed between the groups (Kolseth 2005).1 study · 40 participantsUngraded
Glucosamine sulfate (oral) vs Ibuprofen (oral)
Pain during function (proportion without significant improvement) · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria · 90 days
Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane
Six participants in the glucosamine group did not experience significant improvement in TMJ pain compared with seven in the ibuprofen group (Analysis 3.1); Fisher's exact test P = 0.73 (not significant, per the authors).1 study · 45 participantsUngraded
Titanium (Procera) abutment vs Gold-alloy (machined UCLA) abutment
Success / prosthetic complications (4 years) · Patients with single-tooth implant crowns; split-mouth, 4-year · 4 years
Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane
100% success, no prosthetic complications, and a similar loss of marginal bone (0.4 mm) in both groups (narrative)1 study · 20 participantsUngraded
Sodium hypochlorite 1.3% with MTAD final rinse vs Sodium hypochlorite 1.3% with normal saline final rinse
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
Vital bacterial counts decreased after the active intervention (MTAD) but live bacteria were present in all of the samples; no further usable data reported.1 studyUngraded
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
Topical clobetasol propionate 0.025% vs Topical clobetasol propionate 0.05%
Side-effects reported · People with erosive oral lichen planus
Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane
Table 3 (Side-effects). Carbone 2009: no side-effects.1 study · 35 participantsUngraded
Clobetasol-17-propionate 0.025% lipid-loaded microspheres vs Conventional 0.025% clobetasol lipophilic ointment in hydrophilic phase
Pain reduction (VAS 0-100) · People with erosive oral lichen planus
Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane
MD -18.30 [-28.57, -8.03]1 study · 45 participantsUngraded
Prednisone (oral, commencing 25 mg with phased dose reduction over 2 months) vs Montelukast (leukotriene receptor antagonist)
Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 2 months
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
The study reported more drug-related adverse effects for those treated with prednisone than montelukast.1 study · 40 participantsUngraded
Montelukast (leukotriene receptor antagonist; 10 mg daily for 1 month then alternate days for the second month) vs Placebo
Pain (visual analogue scale) · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 2 months
Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane
MD -1.15 [-1.46, -0.84]1 study · 40 participantsUngraded
RDP with I-bar clasps / mesial rests vs RDP with circumferential clasps / distal rests
Treatment success (5-year) · Partially edentulous patients treated with a removable dental prosthesis (RDP) · 5 years
Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane
HR 0.58 [0.25, 1.34]1 study · 134 participantsUngraded
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
Sodium hypochlorite 5.25% vs Sodium hypochlorite 5.25% with hydrogen peroxide 3%
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
RR 1.22 [0.4, 4.2]1 study · 167 participantsUngraded
LongoVital (herbal component alone) vs Placebo
Adverse effects · 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
Reported adverse events were minor and evenly distributed between the groups (Kolseth 2005). 'Very few and mostly harmless side-effects' were observed (Bratel 2005).2 studiesUngraded
Carboxymethylcellulose (CMC) spray vs Placebo (spray base without CMC / water)
Xerostomia (oral dryness) · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
Donatsky 1982 (crossover, n=15, Sjogren's syndrome): CMC spray had a similar effect on oral dryness to the spray base, but was more effective than water. Paired crossover data not presented; effect size not estimable.1 study · 15 participantsUngraded
Camomile vs Placebo
Oral mucositis (any severity) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.89 [0.62, 1.27]1 study · 164 participantsUngraded
Artificial bone graft: InFuse (collagen matrix) impregnated with rhBMP-2 vs Traditional iliac crest cancellous bone graft
Clinical assessment: alveolar ridge healing (0 to 3 grading scale) · Skeletally mature patients with unilateral cleft lip and palate and an alveolar cleft defect (>5 years; mean age 16.1…
Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate (2011) · Cochrane
MD 0.90 [0.64, 1.16]1 study · 21 participantsUngraded
Indigo wood root vs Saline (placebo)
Oral mucositis (moderate to severe) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.75 [0.5, 1.1]1 study · 20 participantsUngraded
ART sealant using high-viscosity glass ionomer (press-finger technique) vs None (single-arm survival proportion; no comparator)
Sealant retention (partially and fully retained) · Pits and fissures of permanent (posterior) teeth · 4 years, partially and fully retained high-viscosity glass-ionomer ART sealants in permanent dentitions, 4 years
Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis. (2011)
Proportion 0.68 [0.61, 0.75]1 studyUngraded
High-viscosity glass-ionomer ART sealants vs No comparator
Caries-free sealed pits and fissures · Permanent teeth with sealed pits and fissures · 6 years, permanent dentitions with high-viscosity glass-ionomer ART sealants, 6 years
Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis. (2011)
Caries-free percentage 85 [79, 91]1 studyUngraded
Sucralfate vs Placebo/usual care
Oral mucositis (any severity) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.98 [0.88, 1.1]3 studies · 222 participantsModerate
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
High-viscosity glass-ionomer ART restorations vs No comparator
Restoration survival · Permanent posterior teeth with single-surface cavities · 2 years, single-surface permanent posterior teeth, 2 years
Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis. (2011)
Survival percentage 93 [89, 95]13 studiesUngraded
Flossing plus toothbrushing (self-performed; manual or automated floss) vs Toothbrushing alone (with or without a negative-control/placebo rinse)
Plaque (Turesky-modified Quigley-Hein/other plaque indices; SMD) · Dentate adults aged 16 years or older (excluding orthodontic patients and those with severe periodontal disease) · 1 month (mean 29 days)
Flossing for the management of periodontal diseases and dental caries in adults (2011) · Cochrane
SMD -0.23 [-0.52, 0.06]5 studies · 416 participantsVery low
Intestinal trefoil factor vs Placebo
Oral mucositis (severe) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 1.52 [0.06, 36.39]1 study · 99 participantsUngraded
High-viscosity glass-ionomer ART restorations vs No comparator
Restoration survival · Permanent posterior teeth with multiple-surface cavities · 2 years, multiple-surface permanent posterior teeth, 2 years
Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis. (2011)
Survival percentage 41 [18, 67]1 studyUngraded
Reservoir biteguard device releasing a saliva substitute (with KY jelly + Saliva Orthana) vs Biteguard without reservoir (with KY jelly + Saliva Orthana)
Oral health (oral impacts on daily performances) · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
More in the reservoir group experienced relief of an oral impact and fewer a new impact (OIDP), but no difference in the total impact score between groups.1 study · 86 participantsUngraded
Breastfeeding (post cleft-lip surgery) vs Spoon-feeding
Weight (kg) · Infants up to 6 months (from term) born with cleft lip, cleft palate or cleft lip and palate (Pierre Robin sequence or… · 6 weeks post-surgery
Feeding interventions for growth and development in infants with cleft lip, cleft palate or cleft lip and… (2011) · Cochrane
MD 0.47 [0.20, 0.74]1 study · 40 participantsUngraded
Zinc sulphate vs Placebo
Oral mucositis (severe) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.05 [0, 0.75]1 study · 27 participantsUngraded
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
Saliva stimulant lozenge (sorbitol, Sorbee) vs Saliva substitute spray (MouthKote)
Patient preference · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
Stewart 1998: no statistically significant difference in patient preference between lozenge and spray (Analysis 2.3).1 study · 80 participantsUngraded
Dentirol chewing gum (xylitol) vs Profylin lozenge (xylitol/sorbitol + CMC)
Patient preference · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
Patients ranked gum and lozenge equal for preference.1 study · 18 participantsUngraded
Multiple-surface ART restoration using high-viscosity glass ionomer vs None (single-arm survival proportion; no comparator)
Restoration survival · Primary posterior teeth with multiple-surface cavities (children) · 2 years, multiple-surface primary posterior teeth, 2 years
Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis. (2011)
Proportion 0.62 [0.51, 0.73]6 studiesUngraded
Glutamine vs Placebo/usual care
Oral mucositis (any severity) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.78 [0.57, 1.08]5 studiesUngraded
Artificial bone graft: InFuse (collagen matrix) impregnated with rhBMP-2 vs Traditional iliac crest cancellous bone graft
Radiographic assessment: periapical film (0 to 3 grading scale) · Skeletally mature patients with unilateral cleft lip and palate and an alveolar cleft defect (>5 years; mean age 16.1… · 1 year
Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate (2011) · Cochrane
MD 0.60 [0.30, 0.90]1 study · 21 participantsUngraded
Polaprezinc vs Azulene
Oral mucositis (moderate to severe) · Patients with cancer receiving radiotherapy, chemotherapy or targeted therapies · Median 28 days
Interventions for preventing oral mucositis for patients with cancer receiving treatment (2011) · Cochrane
RR 0.43 [0.22, 0.84]1 study · 31 participantsUngraded
Dentirol chewing gum (xylitol) vs Profylin lozenge (xylitol/sorbitol + CMC)
Salivary flow (stimulated whole saliva) · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
No change in stimulated whole saliva.1 study · 18 participantsUngraded
Carboxymethylcellulose (CMC) spray vs Salinum linseed oil spray
Oral health (plaque and gingival indices) · Adults seeking treatment for the symptom of dry mouth (xerostomia) due to any cause (e.g. medication, Sjogren's…
Interventions for the management of dry mouth: topical therapies (2011) · Cochrane
Mean plaque and gingival indices were reduced during the Salinum (linseed) period; incomplete comparative data.1 study · 20 participantsUngraded
Fluoride supplements (tablets, drops, lozenges or chewing gums) vs No fluoride supplement (placebo or no treatment)
Caries increment on permanent tooth surfaces (D(M)FS) · Children and adolescents (aged 16 years or less at baseline) · 24-36 months
Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing dental caries in children (2011) · Cochrane
PF 0.24 [0.16, 0.33]3 studies · 1240 participantsModerate