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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.
75,239 questions in 5,342 reviews
current versionsNo 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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
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 studies | No studies |
Er:YAG laser debridement vs Manual debridement plus chlorhexidine irrigation/gel Change in probing pocket depth (PPD) · People with at least one dental implant affected by peri-implantitis · 6 months Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | No statistically significant differences for change in PPD. | 1 study · 20 participants | Ungraded |
Nanocrystalline hydroxyapatite (Ostim) vs Bovine-derived xenograft (Bio-Oss) plus resorbable barrier Change in gingival recession (REC) · People with at least one dental implant affected by peri-implantitis · 4 years Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | MD -0.10 [-0.51, 0.31] | 1 study · 22 participants | Ungraded |
Subepithelial connective tissue graft (palate) at implant placement vs No augmentation Soft tissue thickness change · Partially edentulous patients receiving posterior mandibular implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | MD -1.35 [-1.78, -0.92] | 1 study · 20 participants | Ungraded |
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 studies | No studies |
Tooth/implant FDP with rigid connectors vs Tooth/implant FDP with non-rigid connectors Natural tooth intrusion · Patients with tooth/implant-supported FDPs; split-mouth · 5 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | Intrusion occurred in 44% of FDPs with rigid connectors and 66% with non-rigid connectors (average 0.18 mm and 0.28 mm respectively) | 1 study · 42 participants | Ungraded |
Fixed partial denture supported by root-formed implants and remaining teeth (tooth/implant-supported) vs Fixed partial denture supported only by root-formed implants (implant-supported) Prosthesis success (10 years) · Partially edentulous patients (mandible) receiving FDPs; split-mouth, 10-year · 10 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 10-year success 85% (17/20) tooth/implant-supported versus 80% (16/20) implant-supported FDPs; not statistically significant; data not available in paired form | 1 study · 23 participants | Ungraded |
Air-abrasive / Vector system debridement vs Manual debridement (carbon fibre curettes) Radiographic marginal bone level · People with at least one dental implant affected by peri-implantitis · 6 months Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | No statistically significant difference for marginal bone levels; data not usable. | 1 study · 11 participants | Ungraded |
Fixed dental prosthesis (cantilever FDP) vs Removable dental prosthesis (RDP) Caries incidence (2 years) · Patients with a shortened dental arch (missing posterior teeth) · 2 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | RR 0.43 [0.21, 0.87] | 1 study · 50 participants | Ungraded |
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 extracted | 0 studies | No 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 studies | No studies |
Clobetasol-17-propionate 0.025% lipid-loaded microspheres vs Conventional 0.025% clobetasol lipophilic ointment in hydrophilic phase Physician Global Assessment (Thongprasom score) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | MD 0.00 [-0.61, 0.61] | 1 study · 45 participants | Ungraded |
Adjunctive local antibiotic (8.5% doxycycline hyclate, Atridox) added to manual debridement vs Manual debridement with chlorhexidine (no antibiotic) Complications and side effects · People with at least one dental implant affected by peri-implantitis · 4 months (18 weeks) Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | No complications occurred in any of the groups. | 1 study · 28 participants | Ungraded |
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 studies | No studies |
1% pimecrolimus cream vs Placebo (vehicle cream) Pain reduction (VAS) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | MD -3.30 [-20.22, 13.62] | 2 studies · 32 participants | Ungraded |
Dietary counselling tailored to a Stage of Change (Transtheoretical Model) to increase fruit and vegetable intake (two counselling sessions) vs Usual care Fruit consumption behaviour: proportion in the Action Stage of Change (versus Pre-Action) · Edentulous patients aged 45 to 80 years attending dental-student teaching clinics for replacement dentures, Newcastle… · 6 weeks after receiving replacement dentures (about 10 weeks after baseline) One‐to‐one dietary interventions undertaken in a dental setting to change dietary behaviour (2012) · Cochrane | At follow-up 75% (22) of the intervention group versus 29% (8) of the control were in the Action Stage of Change for fruit consumption (P<0.001); baseline 20% (6) versus 8% (2). Significant difference between groups.… | 1 study · 58 participants | Ungraded |
Erbium:YAG laser (implant exposure) vs Flap elevation at implant exposure Biological complications · Patients undergoing implant exposure (second-stage surgery) Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 3.0 [0.14, 65.90] | 1 study · 20 participants | Ungraded |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: sagittal changes of B-point (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD -0.22 [-0.58, 0.14] | 1 study · 30 participants | Ungraded |
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 extracted | 0 studies | No studies |
Zirconia abutment vs Titanium abutment Abutment/crown fracture and marginal bone level (3 years) · Patients with single-tooth implant crowns; split-mouth, 3-year · 3 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | No fractures of any abutments or crowns; non-significant differences in mean marginal bone levels, which ranged from 1.6 to 2.1 mm (narrative) | 1 study · 22 participants | Ungraded |
Topical ciclosporin 1.5% gel vs Topical clobetasol propionate 0.025% gel Pain (>=50% improvement in symptoms) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | RR 0.47 [0.17, 1.32] | 1 study · 40 participants | Ungraded |
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 extracted | 0 studies | No 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 extracted | 0 studies | No studies |
Individually designed, patient-centred preventive programme: dietary counselling (snacking timing, regular meals, fermentable carbohydrates) plus toothbrushing counselling, delivered by trained dental hygienists (a multi-intervention) vs Basic prevention offered as standard in public dental clinics Drinking sports drinks no more than once per week · Children aged 11 to 12 years with at least one active initial caries lesion, screened in a town in Finland · 2 to 4 years One‐to‐one dietary interventions undertaken in a dental setting to change dietary behaviour (2012) · Cochrane | Table 2: 87% (218) versus 86% (212) at follow-up (baseline 81% versus 87%). No significant change. | 1 study · 497 participants | Ungraded |
Fixed dental prosthesis (cantilever FDP) vs Removable dental prosthesis (RDP) Patient satisfaction with prosthesis · Patients with a shortened dental arch (missing posterior teeth) Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | RR 1.22 [0.99, 1.51] | 1 study · 54 participants | Ungraded |
Clofazimine (100 mg daily for 30 days, then 100 mg every other 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 | Clofazimine was associated with an increase in cutaneous adverse effects (skin pigmentation and drying) (Fisher's exact test P=0.015), but these were reported to be easily controlled. | 1 study · 43 participants | Ungraded |
LongoVital (herbal component alone) vs Placebo Number of days of ulcers (monthly average) · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 4 to 6 months Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | MD -0.80 [-3.30, 1.70] | 1 study · 50 participants | Ungraded |
Radix tripterygium hypoglaucum tablet (THT) vs Tripterygium glucosides tablet (TGT) Side-effects reported · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | Table 3 (Side-effects). Lin 2005: TGT - menstrual disturbance (6) and leucopenia (1). Tripterygium glucosides are known to be cytotoxic and unsuitable for individuals of child-bearing age. | 1 study · 94 participants | Ungraded |
Er:YAG laser vs Air-abrasive device (Perio-Flow) Radiographic marginal bone level change · People with at least one dental implant affected by peri-implantitis · 6 months Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | After 6 months no statistically significant difference for peri-implant marginal bone levels. | 1 study · 42 participants | Ungraded |
Flapless implant placement vs Conventional flap elevation Implant failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 1.70 [0.32, 8.94] | 2 studies · 96 participants | Ungraded |
Zirconia framework FDP vs Metal framework FDP Survival / framework fracture (3 years) · Patients receiving FDPs; parallel group, 3-year · 3 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 100% survival and no framework fractures in either group after 3 years; no significant differences between groups with respect to porcelain fractures and mean survival time (narrative) | 1 study | Ungraded |
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 studies | No studies |
Crestal incision vs Vestibular incision Biological complications · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | Biological complications: Odds Ratio (M-H, Fixed, 95% CI), Subtotals only (no pooled estimate reported); 1 study (Heydenrijk 2000); 4 crestal vs 1 vestibular had hyperplastic tissue over the healing abutment | 1 study | Ungraded |
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 identified | 0 studies | No studies |
Intraoral vertical ramus osteotomy (IVRO) vs Sagittal split ramus osteotomy (SSRO) Stability of correction: sagittal changes of pogonion (1 week to 1 year) · Adults (16 years of age or older) with an Angle Class III malocclusion (prominent lower front teeth); people with… · 1 week to 1 year post-surgery Treatments for adults with prominent lower front teeth (2012) · Cochrane | MD -0.24 [-0.67, 0.19] | 1 study · 30 participants | Ungraded |
Ciclosporin rinse vs Placebo (vehicle) Side-effects reported · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | Table 3 (Side-effects). Eisen 1990: no adverse side-effects; transient burning sensation of mucosal surfaces during swishing of medication reported in all participants. | 1 study · 8 participants | Ungraded |
Alternative alloy FDP (e.g., Ceramalloy II / base-metal / palladium-silver) vs High-gold content control alloy FDP (Olympia) Laboratory cost per unit · Patients receiving crowns and FDPs; split-mouth, 10-year · 10 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | Gold costs significantly higher: USD 89 per unit for gold compared to USD 53 for palladium-silver alloy and USD 37 for base-metal alloy | 1 study | Ungraded |
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 studies | No studies |
Subantimicrobial dose doxycycline (20 mg twice daily for 90 days) vs Placebo Number of new lesions per day · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 90 days Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | MD -0.19 [-0.35, -0.03] | 1 study · 50 participants | Ungraded |
Tetracycline suspension (250 mg, held in mouth 2 minutes then swallowed, four times daily for 5 days) vs Placebo Adjusted maximum ulcer size and adjusted maximum pain · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 5 days per outbreak Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | A statistically significant difference was shown, in favour of tetracycline, for adjusted maximum ulcer size (P=0.034) and adjusted maximum pain (P=0.017). | 1 study | Ungraded |
Daily multivitamin vs Placebo Duration of episodes · 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 | MD -0.33 [-2.06, 1.40] | 1 study | Ungraded |
LongoVital (herbal component alone) vs Placebo Number of ulcer-free days and number of new ulcers · 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 | Kolseth 2005 (high risk of bias): 40 patients randomised to the herbal component of LongoVital alone or placebo; data presented as medians with 95% CIs, unsuitable for further analysis; no statistically significant… | 1 study · 40 participants | Ungraded |
Tooth/implant FDP with rigid connectors vs Tooth/implant FDP with non-rigid connectors Non-scheduled maintenance visits · Patients with tooth/implant-supported FDPs; split-mouth · 5 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 70 non-scheduled maintenance visits to treat problems with rigid connectors compared to 110 visits for non-rigid connectors; unclear if this difference was considered significant | 1 study · 42 participants | Ungraded |
Vitamin B12 (sublingual, 1000 mcg daily for 6 months) vs Placebo Frequency of outbreaks per month · 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 | MD -8.74 [-16.62, -0.86] | 1 study · 58 participants | Ungraded |
0.1% triamcinolone acetonide in orabase vs Ciclosporin solution Side-effects reported · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | Table 3 (Side-effects). Yoke 2006: no significant adverse events; transient burning sensation upon initial application with both treatments. | 1 study · 15 participants | Ungraded |
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 extracted | 0 studies | No studies |
Flapless implant placement vs Conventional flap elevation Prosthetic failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 1.0 [0.14, 7.10] | 1 study | Ungraded |
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 identified | 0 studies | No studies |
Perilla cooking oil vs Soybean cooking oil Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 8 months Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | No adverse events were reported. | 1 study · 33 participants | Ungraded |
Ciclosporin rinse vs Placebo (vehicle) Physician Global Assessment (severity of disease) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | MD -1.40 [-1.86, -0.94] | 1 study · 8 participants | Ungraded |