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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.
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 |
|---|---|---|---|
Zinc supplements (zinc sulphate, zinc gluconate, zinc picolinate, zinc acetate, or polaprezinc) vs Placebo Taste acuity improvement - objective outcome (dichotomous data) · Patients with taste disturbances (dysgeusia/hypogeusia; idiopathic, zinc-deficient, or secondary to chronic renal… · Mean 3 months, Idiopathic/zinc-deficient taste disorder Interventions for managing taste disturbances (2017) · Cochrane | RR 1.42 [1.09, 1.84] | 2 studies · 292 participants | Very low |
Biperiden plus pilocarpine vs No treatment Dysphagia (WHO grade 3+) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · 12 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | RR 0.25 [0.03, 2.11] | 1 study · 60 participants | Ungraded |
Granulocyte-macrophage colony-stimulating factor (GM-CSF) vs Placebo or no treatment Oral mucositis (severe) · Adults with cancer receiving treatment · RT to head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.31 [0.01, 7.09] | 1 study · 29 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Implant crown complications · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 6.33 [0.26, 152.86] | 1 study · 18 participants | Very low |
Open surgical exposure vs Closed surgical exposure Aesthetics of the treated canine compared with the untreated contralateral canine · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · End of treatment Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | SoF (Aesthetics, reported in various manners at different time points): 'This outcome was measured in a variety of ways in the studies that cannot be pooled'; quality very low (⊕⊝⊝⊝). Results: Parkin 2012 -… | 2 studies | Very low |
Acupuncture vs Sham control (deactivated laser sham acupuncture) Adverse events · Patients with idiopathic dysgeusia and hypogeusia Interventions for managing taste disturbances (2017) · Cochrane | Results: The acupuncture trial (Brandt 2008) did not give any data on adverse events in either group. | 0 studies | No studies |
Fluoride supplementation (tablets, drops, lozenges or chewing gum) vs Placebo or no treatment Decayed or filled primary tooth surfaces at 5 years · Pregnant women (for preventing dental caries in the primary teeth of their children) · 5 years Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing… (2017) · Cochrane | MD -0.05 [-0.42, 0.32] | 1 study · 798 participants | Very low |
Keratinocyte growth factor (KGF; palifermin or repifermin), intravenous vs Placebo Oral mucositis (any severity) · Adults with cancer receiving treatment · Chemotherapy alone for mixed cancers Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.71 [0.60, 0.85] | 2 studies · 215 participants | Ungraded |
Amifostine vs No treatment/placebo Quality of life (Patient Benefit Questionnaire, 10-point scale) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · 12 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | MD 0.70 [0.20, 1.20] | 1 study · 180 participants | Very low |
Chlorhexidine mouthrinse (any concentration; 0.05% to 0.2%) used in conjunction with mechanical oral hygiene procedures vs Placebo/control mouthrinse, or no mouthrinse (mechanical oral hygiene alone); controls pooled (protocol's separate comparisons versus mechanical oral hygiene alone and versus placebo/control merged) Extrinsic tooth staining (various staining indices) · Children or adults with gingivitis or periodontitis capable of performing normal mechanical oral hygiene procedures… · 6 months Chlorhexidine mouthrinse as an adjunctive treatment for gingival health (2017) · Cochrane | SMD 1.54 [1.22, 1.86] | 4 studies · 323 participants | Ungraded |
Bonded molar tubes (attached with adhesive) vs Molar bands (cemented, e.g. with glass ionomer cement) First time failure at tooth level · Participants with full arch fixed orthodontic appliance(s) with molar tubes bonded to first or second permanent… Adhesives for bonded molar tubes during fixed brace treatment (2017) · Cochrane | HR 2.92 [1.80, 4.72] | 2 studies · 190 participants | Ungraded |
Biperiden plus pilocarpine vs No treatment Salivary flow rate (unstimulated) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · End of RT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | Insufficient evidence, from a single trial of 60 participants, to determine the effect on unstimulated salivary flow rate at the end of RT (Rode 1999; Analysis 2.1) | 1 study · 60 participants | Ungraded |
Epidermal growth factor (EGF), oral spray vs Placebo Normalcy of diet (total parenteral nutrition) · Adults with cancer receiving treatment · Chemoradiotherapy to the head and neck Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 1.03 [0.55, 1.94] | 1 study · 136 participants | Ungraded |
Chlorhexidine mouthrinse (any concentration; 0.05% to 0.2%) used in conjunction with mechanical oral hygiene procedures vs Placebo/control mouthrinse, or no mouthrinse (mechanical oral hygiene alone); controls pooled (protocol's separate comparisons versus mechanical oral hygiene alone and versus placebo/control merged) Dental plaque (various plaque indices) · Children or adults with gingivitis or periodontitis capable of performing normal mechanical oral hygiene procedures… · 4 to 6 weeks Chlorhexidine mouthrinse as an adjunctive treatment for gingival health (2017) · Cochrane | SMD -1.45 [-1.90, -1.00] | 12 studies · 950 participants | High |
Intestinal trefoil factor (ITF), oral spray vs Placebo Oral mucositis (severe) · Adults receiving chemotherapy alone for colorectal cancer Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 1.52 [0.06, 36.39] | 1 study · 99 participants | Ungraded |
Open surgical exposure vs Closed surgical exposure Gum health: clinical attachment level (CAL) · People with maxillary palatally displaced (impacted) canines, unilateral or bilateral (children/adolescents; mean ages… · 3 months post-debond Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth (2017) · Cochrane | MD -0.10 [-0.45, 0.25] | 1 study · 62 participants | Low |
Acupuncture vs Sham control (deactivated laser sham acupuncture) Taste acuity improvement · Patients with idiopathic dysgeusia and hypogeusia Interventions for managing taste disturbances (2017) · Cochrane | Results: There were no data on taste acuity improvement in the included acupuncture trial (Brandt 2008). | 0 studies | No studies |
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Periodontal/peri-implant status and occlusal wear (secondary outcomes) · Adults (18 years or older) needing a single crown in the molar or premolar region Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No data were presented for any of the pre-specified secondary outcomes. | 0 studies | No studies |
Bethanechol vs Artificial saliva Quality of life · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on either quality of life or other oral related symptoms were reported. | 0 studies | No studies |
Ibuprofen taken pre-emptively (about 1 hour before treatment) vs Ibuprofen taken post-treatment Adverse events · People undergoing orthodontic treatment (any age; 9 to 34 years in included studies) Pharmacological interventions for pain relief during orthodontic treatment (2017) · Cochrane | No studies in this comparison reported any adverse events. | 0 studies | No studies |
Keratinocyte growth factor (KGF; palifermin or repifermin), intravenous vs Placebo Oral mucositis (severe) · Adults with cancer receiving treatment · RT to head and neck with cisplatin/fluorouracil Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and… (2017) · Cochrane | RR 0.79 [0.69, 0.90] | 3 studies · 471 participants | High |
Selenium vs No intervention Salivary flow rate · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on salivary flow rates were reported. | 0 studies | No studies |
Ormocer-based sealant vs Low-viscosity glass ionomer sealant Dentine caries in permanent molars · Children and adolescents (general population, aged under 20 years) · 24 months Pit and fissure sealants for preventing dental decay in permanent teeth (2017) · Cochrane | Guler 2013 (N=50) compared ormocer-based sealant versus low-viscosity glass ionomer; not separately meta-analysed | 1 study · 50 participants | Ungraded |
Fluoride supplementation (tablets, drops, lozenges or chewing gum) vs Placebo or no treatment Decayed primary surfaces at 5 years · Pregnant women (for preventing dental caries in the primary teeth of their children) · 5 years Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing… (2017) · Cochrane | MD -0.06 [-0.17, 0.05] | 1 study · 798 participants | Ungraded |
Biperiden plus pilocarpine vs No treatment Xerostomia · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No xerostomia data related to the effectiveness of biperiden and pilocarpine were reported (Rode 1999). | 0 studies | No studies |
Antimicrobial lozenge vs Placebo Salivary flow rate · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | No data on salivary flow rates were reported. | 0 studies | No studies |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Aesthetic evaluation (Implant Crown Aesthetic Index, ICAI) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown on… · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | Primary outcome aesthetic evaluation data were reported as the frequency of distribution of the Implant Crown Aesthetic Index (ICAI); no comparative summary estimate was presented. | 2 studies · 47 participants | Very low |
Resorbable (bioresorbable) plates or screws for fixation vs Titanium plates or screws for fixation Satisfactory radiographic appearance (cephalometric radiographs) · Adults (>16 years old) undergoing orthognathic surgery · Up to 3 years postoperatively Resorbable versus titanium plates for orthognathic surgery (2017) · Cochrane | No data available for this outcome. | 0 studies | No studies |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Aesthetic evaluation (patient VAS) · Adults (18 years or older) needing replacement of one premolar or incisor with a cantilevered fixed dental prosthesis · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.34 [-0.85, 0.17] | 1 study · 19 participants | Very low |
ART using H-GIC vs Conventional treatment using amalgam Pain (primary dentition) · Children with dental caries in primary teeth · Single and multiple lesions Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 1.44 [0.45, 4.60] | 1 study | Ungraded |
Chlorhexidine mouthrinse (any concentration; 0.05% to 0.2%) used in conjunction with mechanical oral hygiene procedures vs Placebo/control mouthrinse, or no mouthrinse (mechanical oral hygiene alone); controls pooled (protocol's separate comparisons versus mechanical oral hygiene alone and versus placebo/control merged) Extrinsic tooth staining (various staining indices) · Children or adults with gingivitis or periodontitis capable of performing normal mechanical oral hygiene procedures… · 4 to 6 weeks Chlorhexidine mouthrinse as an adjunctive treatment for gingival health (2017) · Cochrane | SMD 1.07 [0.80, 1.34] | 8 studies · 415 participants | Moderate |
Amifostine (intravenous) vs Amifostine (subcutaneous) Xerostomia (grade >= 2, 0-4 scale) · Patients receiving radiotherapy on its own or in addition to chemotherapy to the head and neck region · Up to and including 3 months postRT Pharmacological interventions for preventing dry mouth and salivary gland dysfunction following radiotherapy (2017) · Cochrane | RR 1.03 [0.76, 1.40] | 1 study · 263 participants | Ungraded |
ART using resin-modified glass ionomer cement (RM-GIC) vs Conventional treatment using RM-GIC Restoration failure (permanent, mature dentition; root surfaces) · Older adults with root caries in permanent (mature) teeth (mean age 75 years) · 6 months, Root caries Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 2.71 [0.94, 7.81] | 1 study · 64 participants | Very low |
Oral health education (advice and training) vs Standard care (oral health advice not specifically emphasised beyond usual care) Service use: Emergency medical/dental treatment · People with serious mental illness (all included participants had schizophrenia); majority aged 18 to 65 years per… Oral health education (advice and training) for people with serious mental illness (2016) · Cochrane | No study reported useable data | 0 studies | No studies |
Dietary supplements (alpha lipoic acid +/- vitamins/lycopene/green tea; hypericum; Catuama; lycopene) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF5 Dietary supplements vs placebo. Symptom relief short-term: insufficient or contradictory evidence regarding benefit of any evaluated dietary supplement; 628 participants (12 RCTs); very low. Subgroups: ALA without… | 12 studies · 628 participants | Very low |
Educational intervention with information and practical components (theoretical oral health education plus practical skills training) for nursing staff and/or residents vs (Optimised) usual care Denture plaque · Nursing home residents (mean age 78.3 to 86.0 years; more than 66% women; 62.1% to 87.3% with dental prostheses) · 3 to 60 months Oral health educational interventions for nursing home staff and residents (2016) · Cochrane | SMD -0.60 [-1.25, 0.05] | 5 studies · 816 participants | Low |
Chemically cured glass ionomer cement vs Light-cured compomer (polyacid-modified composite resin) Taste preference (patient preference) · Patients with full arch fixed orthodontic appliances with bands attached to molars (patients with cleft lip/palate or… · Approximately 12 months (to end of treatment) Adhesives for fixed orthodontic bands (2016) · Cochrane | Williams 2005 (30 participants): a statistically significant difference in patient taste preference in favour of the glass ionomer over the light-cured composite resin (compomer). | 1 study · 30 participants | Ungraded |
Topical treatments (benzydamine hydrochloride oral rinse) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), benzydamine hydrochloride Interventions for treating burning mouth syndrome (2016) · Cochrane | SoF9 Topical treatments vs placebo. Symptom relief short-term: insufficient or contradictory evidence regarding benefit of any evaluated topical treatment; 150 participants (4 RCTs); very low. Subgroups: benzydamine (1… | 4 studies · 150 participants | Very low |
NSAIDs (ketorolac oral rinse; systemic celecoxib) vs Placebo or no treatment Clinical resolution (oral lesion not completely resolved) · People with a diagnosis of oral leukoplakia · 3 months Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | SoF 3, Clinical resolution (not completely resolved) at 3 months: '1 study evaluated systemic treatment and 1 evaluated topical treatment. Neither found benefit for NSAIDs.' No GRADE. Effects text: celecoxib… | 2 studies | Ungraded |
Adhesively bonded amalgam restorations in conventional preparations utilising deliberate retention (all bonding agents) vs Traditional non‐bonded amalgam restorations Marginal deterioration of the restoration and fracture of the remaining tooth tissue · Adults and adolescents with permanent posterior molar and premolar teeth suitable for Class I and II, but excluding… · Mean 24 months Adhesively bonded versus non‐bonded amalgam restorations for dental caries (2016) · Cochrane | Marginal deterioration of the restoration and fracture of the remaining tooth tissue - Follow‐up: mean 24 months | Study population | Relative effect (95% CI): Not estimable | Number of participants (studies): 31 (1… | 1 study · 31 participants | Low |
Mineral trioxide aggregate (MTA) root-end filling vs SuperEBA Healing - 1 year · People requiring retreatment of periapical lesions (failed root canal therapy) · 1 year Endodontic procedures for retreatment of periapical lesions (2016) · Cochrane | RR 0.97 [0.91, 1.04] | 1 study · 192 participants | Low |
Job-related or family-related stress and pessimistic attitude to life vs Lower stress and no pessimistic attitude Periodontal disease and serum IL-1β IL-6 and cortisol · Patients with aggressive or chronic periodontitis at a university periodontology department Social-Biological Interactions in Oral Disease: A 'Cells to Society' View. (2016) | no estimate extracted | 1 study · 80 participants | Ungraded |
Educational intervention with information and practical components (theoretical oral health education plus practical skills training) for nursing staff and/or residents vs (Optimised) usual care Caries/root caries · Nursing home residents (mean age 78.3 to 86.0 years; more than 66% women; 62.1% to 87.3% with dental prostheses) · 6 to 18 months Oral health educational interventions for nursing home staff and residents (2016) · Cochrane | SoF: Caries/root caries (follow-up 6 to 18 months). No meta-analysis. 178 participants (2 RCTs); low quality. Comment: 2 studies at unclear (Frenkel 2001) or high risk of bias (Mojon 1998) showed no apparent… | 2 studies · 178 participants | Low |
Vitamin A or retinoids (systemic or topical; incl. 13-cis-retinoic acid, acitretin) vs Placebo or no treatment Oral cancer development · People with a diagnosis of oral leukoplakia · 24 months (treatment lasted 12 months) Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 0.11 [0.01, 2.05] | 1 study · 85 participants | Very low |
Topical bleomycin vs Placebo or no treatment Oral cancer development · People with a diagnosis of oral leukoplakia · up to 7 years Interventions for treating oral leukoplakia to prevent oral cancer (2016) · Cochrane | RR 3.00 [0.32, 27.83] | 1 study · 20 participants | Very low |
Perioperative infraorbital nerve block vs Infiltration of the incision (peri-incisional infiltration) Duration of postoperative analgesia · Children up to 13 years of age, undergoing cleft lip repair surgery Infraorbital nerve block for postoperative pain following cleft lip repair in children (2016) · Cochrane | This outcome was not reported. | 0 studies | No studies |
Light-cured resin-modified glass ionomer cement vs Light-cured compomer (polyacid-modified composite resin) Band failure (band adhesive loosening) · Patients with full arch fixed orthodontic appliances with bands attached to molars (patients with cleft lip/palate or… · Approximately 12 months (to end of treatment) Adhesives for fixed orthodontic bands (2016) · Cochrane | Fricker 1997 was a three-arm split-mouth trial that included a light-cured resin-modified glass ionomer arm (compared with light-cured compomer and chemically cured glass ionomer). Failure rates were reported but not… | 1 study | Ungraded |
Adhesively bonded amalgam restorations in conventional preparations utilising deliberate retention (all bonding agents) vs Traditional non‐bonded amalgam restorations Survival of the restoration · Adults and adolescents with permanent posterior molar and premolar teeth suitable for Class I and II, but excluding… · Mean 24 months Adhesively bonded versus non‐bonded amalgam restorations for dental caries (2016) · Cochrane | Survival of the restoration - Follow‐up: mean 24 months | Illustrative comparative risks: Assumed risk (Control) See comment; Corresponding risk (Adhesive bonding) See comment | Relative effect (95% CI): Not estimable… | 1 study · 31 participants | Low |
Benzodiazepines (topical clonazepam) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months), topical clonazepam Interventions for treating burning mouth syndrome (2016) · Cochrane | MD -1.89 [-2.19, -1.59] | 2 studies · 111 participants | Very low |
Anticonvulsants (gabapentin 300 mg/day, +/- alpha lipoic acid) vs Placebo Relief of burning/discomfort (symptom relief; pain intensity) · People with primary burning mouth syndrome (BMS), that is, oral mucosal pain with no dental or medical cause for such… · short-term (up to 3 months) Interventions for treating burning mouth syndrome (2016) · Cochrane | RR 4.00 [2.09, 7.67] | 1 study · 100 participants | Very low |