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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.
10,375 questions in 429 reviews · Oral Health
current versionsNo studies 1,344 · 13%Ungraded 6,832 · 65.9%Very low 1,228 · 11.8%Low 613 · 5.9%Moderate 290 · 2.8%High 68 · 0.7%
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 |
|---|---|---|---|
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 identified | 0 studies | No studies |
Crestal incision vs Vestibular incision Implant failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 3.0 [0.15, 59.89] | 1 study · 10 participants | Ungraded |
Montelukast (leukotriene receptor antagonist; 10 mg daily for 1 month then alternate days for the second month) vs Placebo 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 -3.90 [-4.55, -3.25] | 1 study · 40 participants | Ungraded |
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 studies | No studies |
Nanocrystalline hydroxyapatite (Ostim) vs Bovine-derived xenograft (Bio-Oss) plus resorbable barrier Recurrence of peri-implantitis · People with at least one dental implant affected by peri-implantitis · 4 years Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | RR 2.0 [0.21, 18.98] | 1 study · 22 participants | Ungraded |
Implant surface smoothening added to systemic antibiotics + resective surgery + local antibiotics vs No implant surface smoothening (same surgical protocol) Complications and side effects · People with at least one dental implant affected by peri-implantitis · 2 years Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | No complications occurred in any of the groups. | 1 study · 17 participants | Ungraded |
Aloe vera gel vs Placebo Pain (>=50% improvement in symptoms) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | RR 6.16 [2.35, 16.13] | 1 study · 45 participants | Ungraded |
Glucosamine sulfate (oral) vs Ibuprofen (oral) Brief Pain Inventory (BPI) - pain interference, change from baseline · 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 | MD -6.74 [-14.70, 1.22] | 1 study · 45 participants | Ungraded |
Levamisole (150 mg per day) vs Placebo Decrease in number of ulcers · 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 | RR 7.88 [0.51, 121.96] | 1 study | Ungraded |
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 studies | No studies |
Pentoxifylline (400 mg three times daily for 60 days) vs Placebo Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 60 days (plus 60-day follow-up) Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | Patients receiving pentoxifylline reported more adverse events than those in the placebo group but this was not statistically significant (69% reported adverse effects: dizziness, headaches, stomach upset, increased… | 1 study · 26 participants | Ungraded |
Diclofenac sodium (oral NSAID) vs Occlusal splint therapy Morphological changes of the TMJs (assessed by CT) · 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 study reports morphological changes assessed by CT for the entire sample without distinction of group, so extraction was not possible. | 1 study | Ungraded |
30 minutes of one-to-one instruction by a dental hygienist covering the relationship between sugar consumption and dental health, plus oral hygiene, fluoride and regular dental visits (a multi-intervention) vs No instruction Mean sugar consumption (self-reported, 1 to 5 scale; higher score = more positive behaviour) · Adults newly registered at a group dental practice in a suburban Dutch village, the Netherlands · 6 to 12 months One‐to‐one dietary interventions undertaken in a dental setting to change dietary behaviour (2012) · Cochrane | Table 3, mean (SD) sugar consumption (1-5 scale): instruction group 3.41 (1.50) at baseline to 3.58 (1.07) at follow-up (significant versus baseline); control 2.89 (0.99) to 2.88 (1.27). The review judges the results… | 1 study | Ungraded |
Colchicine (0.5 mg per day for 3 months) vs Prednisolone (5 mg per day for 3 months) Number of aphthous ulcers at completion · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 3 months Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | MD -0.13 [-0.50, 0.24] | 1 study · 34 participants | Ungraded |
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 extracted | 0 studies | No 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 studies | No 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 extracted | 0 studies | No studies |
Diclofenac sodium (oral NSAID) vs Occlusal splint therapy Pain (on movement and on palpation of the affected TMJ) · Adults (>18 years) with temporomandibular joint osteoarthritis (TMJ OA) diagnosed by RDC/TMD or compatible criteria · 1 week and 3 months Interventions for managing temporomandibular joint osteoarthritis (2012) · Cochrane | Data for pain on movement or pain on palpation of the affected TMJ (both at 1 week and 3 months) could not be extracted, as they are described as percentages of an unclear total number. Narratively, diclofenac sodium… | 1 study | Ungraded |
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 Dental caries increment: DMFS increment after 2 years · Children aged 11 to 12 years with at least one active initial caries lesion, screened in a town in Finland · 2 years One‐to‐one dietary interventions undertaken in a dental setting to change dietary behaviour (2012) · Cochrane | Mean (95% CI) DMFS increment after 2 years: intervention 1.86 (1.50 to 2.21) versus control 2.44 (2.12 to 2.77); significant difference favouring the intervention (P<0.05, comparing intervention and control). No… | 1 study · 497 participants | Ungraded |
Colchicine (0.5 mg per day for 3 months) vs Prednisolone (5 mg per day for 3 months) Adverse effects · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 3 months Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | Colchicine was associated with statistically significantly more adverse effects than prednisolone (nine participants reporting adverse effects on colchicine versus two on prednisolone). | 1 study · 34 participants | Ungraded |
Tetracycline suspension (250 mg, held in mouth 2 minutes then swallowed, four times daily for 5 days) vs Placebo Adverse effects · 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 | Adverse event rates were comparable between groups. | 1 study | Ungraded |
Ciclosporin rinse vs Placebo (vehicle) Pain reduction (participant-reported symptoms) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | We were unable to extract data on participant-reported symptoms for Eisen 1990 because there was no breakdown of data for the ELP subgroup. | 1 study · 8 participants | Ungraded |
Chlorhexidine 0.2% 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 | Positive bacterial cultures at end of first appointment: 65% of samples (chlorhexidine 0.2%) vs 89% (normal saline); no further data reported. | 1 study | Ungraded |
Colchicine (0.5 mg per day for 3 months) vs Prednisolone (5 mg per day for 3 months) Recurrence during treatment period · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 3 months Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | RR 1.30 [0.98, 1.71] | 1 study · 34 participants | Ungraded |
Topical clobetasol propionate 0.025% vs Topical clobetasol propionate 0.05% Partial response (partial or complete response) · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | RR 1.18 [0.82, 1.70] | 1 study · 35 participants | Ungraded |
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 Using xylitol products more than 3 times per day · 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 | RR 1.32 [1.04, 1.68] | 1 study · 497 participants | Ungraded |
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 extracted | 0 studies | No 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 studies | No studies |
Subepithelial connective tissue graft (palate) at implant placement vs No augmentation Aesthetics (pink aesthetic score, PES) evaluated by dentist · Partially edentulous patients receiving posterior mandibular implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | MD -2.87 [-3.67, -2.07] | 1 study · 20 participants | Ungraded |
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 extracted | 0 studies | No studies |
Sodium hypochlorite 5% (also 2.5%) vs Sodium hypochlorite 1% 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 | RR 0.22 [0.051, 0.91] | 1 study · 111 participants | Ungraded |
Topical tacrolimus 0.1% ointment vs Topical clobetasol propionate 0.05% ointment Reduction in target/mean lesion size · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | MD 0.00 [-1.09, 1.10] | 1 study · 29 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) Alveolar bone loss · Partially edentulous patients (mandible) receiving FDPs; split-mouth, 10-year · 10 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | No significant differences in alveolar bone loss: 0.6 to 0.7 mm for implant-supported versus 0.5 mm for tooth/implant FDPs (narrative) | 1 study · 23 participants | Ungraded |
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 studies | No studies |
Tilting-type RDP (minor connector design) vs Functional and sanitary RDP designs Patient satisfaction · Partially edentulous patients with a distal-extension RDP (minor connector); cross-over Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | The tilting-type RDP significantly outscored the functional and sanitary designs for patient satisfaction; within-patient SDs not given, data narrative only | 1 study · 25 participants | Ungraded |
RDP with lingual plate major connector vs RDP with sublingual bar major connector Abutment tooth mobility (Periotest) at 30 months · Partially edentulous patients treated with a mandibular RDP (major connector) · 30 months Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | MD -1.99 [-3.36, -0.62] | 1 study · 36 participants | Ungraded |
Fluocinonide in adhesive base vs Placebo Side-effects reported · People with erosive oral lichen planus Interventions for erosive lichen planus affecting mucosal sites (2012) · Cochrane | Table 3 (Side-effects). Voute 1993: no side-effects during the study and follow-up period. | 1 study · 27 participants | Ungraded |
One-to-one advice on sugar restriction: detailed information on the sugar content of foods, with instruction to refrain from sugar-containing foods between meals and to reduce sugar in main meals (6-week sugar restriction) vs No advice on sugar restriction Total sugar intake frequency (mean number of intakes per day) · Adults with frequent sugar intake harbouring Streptococcus mutans and Streptococcus sobrinus in saliva (14 dental… · Follow-up at 3, 6 and 12 weeks One‐to‐one dietary interventions undertaken in a dental setting to change dietary behaviour (2012) · Cochrane | Table 5, total mean (SD) intakes/day: intervention 9.5 (1.9) baseline, 1.6 (1.4) at 3 weeks, 1.8 (1.5) at 6 weeks, 7.8 (3.5) at 12 weeks; control 7.2 (2.6), 7.1 (3.7), 6.5 (4.2), 6.7 (2.2). Significant reduction versus… | 1 study · 20 participants | Ungraded |
Levamisole 50 mg three times per day for days 1 and 2 vs Levamisole 50 mg three times per day for day 1 and placebo for day 2 (lower dose) Overall effectiveness (all parameters) · Participants with a previous or current history of recurrent aphthous stomatitis (RAS), diagnosed on history and… · 16 weeks Systemic interventions for recurrent aphthous stomatitis (mouth ulcers) (2012) · Cochrane | A trial at high risk of bias (Zissis 1983) compared two different dose regimens of levamisole (treatment 2 days per week for 16 weeks; a third group received placebo). There was inconsistency in the presentation of the… | 1 study | Ungraded |
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 extracted | 0 studies | No 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 studies | No 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 participants | Ungraded |
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 extracted | 0 studies | No 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 study | Ungraded |
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 participants | Ungraded |
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 extracted | 0 studies | No 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 extracted | 0 studies | No 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 participants | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |