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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 |
|---|---|---|---|
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs Educational intervention (oral hygiene education/instruction) Plaque score · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) · 5 weeks (2 weeks post-intervention) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Stewart 1991: while the educational intervention group and the cognitive behavioural intervention group both showed significant differences compared to the control group in plaque scores, the cognitive behavioural… | 1 study · 50 participants | Ungraded |
Antifungal drugs not absorbed from GI tract vs Placebo or no treatment Systemic fungal infection · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.1 [0.01, 1.75] | 2 studies · 71 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs Educational intervention (oral hygiene education/instruction) Self-reported flossing · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) · 5 weeks (2 weeks post-intervention) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Stewart 1991: there were no differences between the educational intervention group and the cognitive behavioural (psychological) intervention group for self reported flossing; improvements in flossing could not be… | 1 study · 50 participants | Ungraded |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Toxicity (adverse events probably due to drug) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 1.18 [0.84, 1.67] | 3 studies · 871 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs No (active) intervention (usual/standard dental care or no-treatment control) Self-reported tooth brushing · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Self assessed brushing was assessed in two studies (Little 1997; Stewart 1991); both found the intervention groups reported improved brushing. Little 1997: Analysis of Covariance found significant differences favouring… | 2 studies | Ungraded |
Ketoconazole vs Itraconazole Oral candidiasis (present) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | 1 study (Caselli 1990); no evidence of a difference; not estimable/not pooled | 1 study | Ungraded |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Oral candidiasis (present) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.47 [0.29, 0.78] | 7 studies · 1153 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs Educational intervention (oral hygiene education/instruction) Dental knowledge · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Stewart 1996: there was no difference in change in dental knowledge at post-intervention between the educational and psychological groups (both improved significantly relative to control). | 1 study · 78 participants | Ungraded |
Antifungal drugs absorbed from GI tract vs Antifungal drugs not absorbed from GI tract Toxicity (adverse events probably due to drug) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.88 [0.33, 2.3] | 6 studies · 2018 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs Educational intervention (oral hygiene education/instruction) Self-efficacy beliefs (flossing) · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Stewart 1996: the psychological intervention group demonstrated significantly higher change in self efficacy scores for flossing at post-intervention compared to the educational group (there was no difference in the… | 1 study · 78 participants | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Sites failing to gain 2 mm attachment (proportion) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | RR 0.54 [0.31, 0.96] | 6 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Aesthetics (patient's opinion) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Tongue scraping (mechanical tongue cleaning) vs Placebo or no intervention (nothing) Outcome NR · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | No eligible randomized controlled trials comparing tongue scraping with placebo or no intervention were identified. | 0 studies | No studies |
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium) Tactile sensitivity (method a, ordinal scale) · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane | MD -0.65 [-1.07, -0.23] | 1 study | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Change in gingival recession · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 0.26 [0.08, 0.43] | 9 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Treatment / surgical procedure time · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 23.9 | 1 study | Ungraded |
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium) Thermal sensitivity · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane | MD -1.10 [-1.64, -0.55] | 1 study | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Change in clinical attachment level (attachment gain) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 1.22 [0.80, 1.64] | 16 studies | Ungraded |
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium) Subjective assessment of sensitivity · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane | SMD -0.67 [-1.44, 0.10] | 3 studies · 206 participants | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Hard tissue probing at surgical re-entry (bone gain) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 1.39 [1.08, 1.71] | 3 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Cost/benefit (treatment time plus estimated material costs) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery) Hard tissue probing at surgical re-entry (bone gain) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 3.37 [3.14, 3.61] | 1 study | Ungraded |
Tongue scraper or tongue cleaner (One Drop Only tongue cleaner; Tongue-Putzer scraper; polystyrene scraper) vs Toothbrush (used to clean the tongue) Volatile sulfur compound (VSC) levels measured by portable sulfide monitor · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Immediately to 35 min post-intervention (Seemann 2001); 1 week (Pedrazzi 2004) Tongue scraping for treating halitosis (2006) · Cochrane | No summary of findings table or GRADE assessment (pre-GRADE review); narrative synthesis, data not pooled. Seemann 2001: peak VSC reduction 42% with the tongue cleaner, 40% with the tongue scraper and 33% with the… | 2 studies · 40 participants | Ungraded |
Tongue scraper or tongue cleaner (One Drop Only tongue cleaner; Tongue-Putzer scraper; polystyrene scraper) vs Toothbrush (used to clean the tongue) Adverse effects (tongue trauma, nausea) and acceptability · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · 1 week (Pedrazzi 2004) Tongue scraping for treating halitosis (2006) · Cochrane | Pedrazzi 2004: six of ten (60%) participants complained of nausea and one participant of tongue trauma, only with the toothbrush; all participants were receptive to the tongue scraper. Seemann 2001: no adverse effects… | 2 studies | Ungraded |
Tongue scraper or tongue cleaner (One Drop Only tongue cleaner; Tongue-Putzer scraper; polystyrene scraper) vs Toothbrush (used to clean the tongue) Self-expressed (perceived) or organoleptic (human nose) assessment of halitosis · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | Neither of the two included trials provided any self expressed (perceived) or organoleptic (human nose) assessments of halitosis (the review's primary outcomes); no data. | 0 studies | No studies |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Radiographic bone change · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | Radiographic data was contained in two studies. Mayfield 1998 showed 0.6 mm gain in bone from the base of the defect in both test and control groups; Ratka-Kruger 2000 reported descriptively that only minute changes in… | 2 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Tooth loss · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No tooth loss was reported in any study although these data are incomplete where patient follow-up was not complete (no events; no estimable effect). | 17 studies | Ungraded |
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery) Change in clinical attachment level (attachment gain) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 1.25 [0.89, 1.61] | 2 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Change in probing depth (probing depth reduction) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 1.21 [0.53, 1.88] | 11 studies | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Disease recurrence (% sites with >=2 mm loss of probing attachment from 12 months after treatment) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium) Air blast sensitivity · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane | SMD -1.25 [-1.65, -0.85] | 6 studies · 392 participants | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Ease of maintenance (% of sites with <4 mm probing depth) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Potassium containing toothpaste (5% potassium nitrate) vs Control toothpaste (without potassium) Tactile sensitivity (method b, continuous probe) · Healthy human adults (18 years or more) with dentine hypersensitivity from exposed root surfaces · 6 to 8 weeks Potassium containing toothpastes for dentine hypersensitivity (2006) · Cochrane | SMD 1.19 [0.79, 1.59] | 5 studies · 356 participants | Ungraded |
Tongue scraping (mechanical tongue cleaning) vs Mouthwash or other chemical intervention Outcome NR · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | No randomized controlled trials comparing mechanical tongue cleaning with mouthwashes were identified; the review notes "the somewhat unexpected lack of randomized controlled trials comparing the effectiveness of… | 0 studies | No studies |
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery) Change in probing depth (probing depth reduction) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD 1.24 [0.89, 1.59] | 2 studies | Ungraded |
Guided tissue regeneration (GTR) combined with bone substitutes/graft vs Open flap debridement (access flap surgery) Change in gingival recession · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… · >=12 months Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | MD -0.33 [-0.43, -0.23] | 1 study | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Patient well-being / quality of life · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | Cortellini 2001: 36% of GTR patients reported the procedure interfered with daily activity for an average of 2.7 days versus 32% of controls for an average of 2.4 days; no significant difference for postoperative pain… | 1 study | Ungraded |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Post-operative complications / adverse effects (including pain, infection) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | Adverse effects were generally minor. Healing was generally uneventful for both test and control groups. Exposure of the GTR barrier membrane was widely reported, ranging from 20% of sites (non-resorbable… | 16 studies | Ungraded |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Number of denture adjustments required · Edentulous adult patients requiring complete dentures · 3 weeks per denture set (cross-over) Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | No statistically significant difference was found between the two occlusal patterns with regard to the number of adjustments required. | 1 study · 30 participants | Ungraded |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived comfort · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived masticatory/chewing efficiency · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived satisfaction (denture preference) · Edentulous adult patients requiring complete dentures · 3 weeks per denture set (cross-over) Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | OR 10 [2.04, 48.96] | 1 study · 30 participants | Ungraded |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived masticatory/chewing function · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Stabilisation splint (SS) vs Minimal/no treatment Pain (severity/palpation; PSS, PPI, VAS) · Patients with pain dysfunction syndrome (PDS) of all degrees of severity · 3 months or less Stabilisation splint therapy for temporomandibular pain dysfunction syndrome (2004) · Cochrane | MD -3.20 [-4.81, -1.59] | 4 studies | Ungraded |
Fluoride toothpaste vs Fluoride mouthrinse Unacceptability of treatment (drop-outs) · Children or adolescents aged 16 or less at the start of the study One topical fluoride (toothpastes, or mouthrinses, or gels, or varnishes) versus another for preventing… (2004) · Cochrane | RR 0.89 [0.78, 1.00] | 5 studies | Ungraded |
Fluoride toothpaste vs Fluoride mouthrinse Proportion of children developing new caries (permanent) · Children or adolescents aged 16 or less at the start of the study One topical fluoride (toothpastes, or mouthrinses, or gels, or varnishes) versus another for preventing… (2004) · Cochrane | RR 0.90 [0.60, 1.37] | 1 study | Ungraded |
Fluoride mouthrinse combined with fluoride toothpaste vs Fluoride mouthrinse alone Caries increment in permanent teeth: D(M)FS (prevented fraction) · Children or adolescents aged 16 years or less · Nearest to 3 years Combinations of topical fluoride (toothpastes, mouthrinses, gels, varnishes) versus single topical fluoride… (2004) · Cochrane | PF 0.05 [-0.05, 0.15] | 4 studies · 1678 participants | Ungraded |
Stabilisation splint (SS) vs Jaw exercises TMJ clicking · Patients with pain dysfunction syndrome (PDS) of all degrees of severity · up to 6 months Stabilisation splint therapy for temporomandibular pain dysfunction syndrome (2004) · Cochrane | SS vs jaw exercises (Magnusson 1999): TMJ clicking at 3 months and greater than 3 months; no statistically significant between-group difference. Forest-plot data presented, totals not pooled. | 1 study | Ungraded |
Stabilisation splint (SS) vs Visual feedback Movement (lateral mandibular movement) · Patients with pain dysfunction syndrome (PDS) of all degrees of severity · 3 months or less Stabilisation splint therapy for temporomandibular pain dysfunction syndrome (2004) · Cochrane | SS vs visual feedback (Monteiro 1988): both SS and visual feedback groups showed a significant decrease in lateral mandibular movement scores (P<0.01); data were unavailable for analysis. | 1 study | Ungraded |
Fluoride mouthrinse combined with fluoride toothpaste vs Fluoride mouthrinse alone Unacceptability of treatment (drop-outs / leaving study early) · Children or adolescents aged 16 years or less Combinations of topical fluoride (toothpastes, mouthrinses, gels, varnishes) versus single topical fluoride… (2004) · Cochrane | RR 0.88 [0.67, 1.17] | 3 studies · 1697 participants | Ungraded |