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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 |
|---|---|---|---|
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration All cause mortality · Patients with chronic kidney disease Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.86 [0.81, 0.92] | 10 studies · 6853 participants | Ungraded |
Osteotomes with mallet (Summers' technique) vs Rotary instruments (Cosci technique) Prosthesis failure · Patients undergoing crestal maxillary sinus lift · 3 years after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Checchi 2010 (split-mouth, N = 12): no prosthetic failures in either group. | 1 study · 12 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Metabolic syndrome (prevalent) · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.49 [0.38, 0.64] | 8 studies · 31416 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Patient acceptability · Patients of any age undergoing orthodontic treatment with fixed appliances and requiring anchorage (adolescents to… Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | Reported narratively in 1 study (Feldmann 2007): limitations in daily life and jaw function were low to moderate throughout the trial with no differences between anchorage groups; impact on mood and appearance peaked… | 1 study · 113 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Performance measures: muscle strength · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD -0.19 [-0.35, -0.02] | 3 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Cognition · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.42 [0.34, 0.53] | 7 studies · 9004 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Pre-eclampsia · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.56 [0.39, 0.80] | 9 studies · 3230 participants | Ungraded |
Powered toothbrush (any mode of action) vs Manual toothbrush Calculus · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… Powered versus manual toothbrushing for oral health (2014) · Cochrane | Three trials reported on calculus: two no significant difference; one favoured the powered brush at six months (P<0.01). | 3 studies | Ungraded |
Colchicine (systemic; 0.5 mg weight-adjusted daily) vs Placebo Total number of oral ulcers · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · 24 months Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD 2.30 [-3.42, 8.02] | 1 study · 115 participants | Moderate |
Vitamin D supplementation vs Placebo or control Fractures: non-vertebral, non-hip · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.69 [0.21, 1.66] | 2 studies | Ungraded |
Southern regular implants vs Southern wide implants Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 year Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 3.25 [0.15, 72.36] | 1 study · 23 participants | Ungraded |
Sinus lift with bone graft (granular Bio-Oss) vs Sinus lift without bone graft (Inion resorbable rigid barrier maintaining space / no bone) Bone gain · Patients with an atrophic maxillary sinus requiring augmentation (1 to 5 mm residual bone height) · 18 months after augmentation Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | MD -0.10 [-0.47, 0.27] | 1 study · 39 participants | Ungraded |
Turned (smoother) implant surfaces vs Roughened implant surfaces Early implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · before prosthetic loading, turned vs roughened surfaces Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 2.79 [0.87, 8.90] | 7 studies · 404 participants | Low |
Systemic interventions (aciclovir, thalidomide, corticosteroids, rebamipide, etanercept, colchicine, interferon-alpha) vs Placebo Pain associated with oral ulcers · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | SoF 2 (systemic interventions vs placebo), grouped comment spanning all four listed outcomes (verbatim; the review's wording "topical" is a typo for systemic): "8 placebo-controlled trials evaluated topical… | NR | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Participant satisfaction · Children and young people aged 17 years or younger having dental treatment (including extractions) under general… Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane | The study did not report on patient or child satisfaction | 0 studies | No studies |
Astra TiO2-blasted titanium screws vs Branemark turned titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 5 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.25 [0.03, 2.12] | 1 study · 66 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Adverse events · Patients of any age undergoing orthodontic treatment with fixed appliances and requiring anchorage (adolescents to… Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | This outcome was unreported in all included studies | 0 studies | No studies |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Head circumference · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.05 [-0.24, 0.34] | 2 studies · 840 participants | Ungraded |
Bone graft with platelet-rich plasma (PRP) vs Bone graft without PRP Complications · Patients with insufficient bone below the maxillary sinus requiring dental implants · 2 years after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Raghoebar 2005: 1 complication in the non-PRP arm, OR 0.27 (0.01 to 8.46), P = 0.46; Torres 2009 (PRP only = 3, no-PRP only = 2), OR 1.49 (0.15 to 15.07), P = 1.00. No statistically significant difference. | 2 studies · 62 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Diastolic blood pressure · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -0.03 [-1.98, 1.92] | 3 studies | Ungraded |
One-stage crestal-approach sinus lift with autogenous bone and 8 mm implants vs Lateral-window sinus lift with 50% autogenous bone/50% Bio-Oss and implants at least 10 mm long Complications · Patients with 3 to 6 mm of residual bone height at the sinus floor · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 0.21 [0.02, 2.08] | 1 study · 40 participants | Ungraded |
Powered toothbrush, rotation oscillation action vs Manual toothbrush Plaque score (>3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Long term (>3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.66 [-1.28, -0.03] | 7 studies · 527 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Mean gestational age at delivery · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.17 [-0.16, 0.51] | 2 studies | Ungraded |
Removable appliance with palatal crib associated with high-pull chincup vs No treatment Alteration of hyperdivergent growth pattern · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… · End of treatment (12 months) Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | The angles (SN.GoGN, SN.PP, NS.Gn) and linear measures (AFA, AFP, AFAI) did not demonstrate significant alterations between groups; interventions did not produce significant changes in the skeletal maxillary or… | 1 study | Ungraded |
SPI Element sand-blasted acid-etched standard implants vs SPI Element SurfLink-modified implants Marginal bone level change · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 year Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | MD 0.27 [-0.01, 0.55] | 1 study · 42 participants | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Complications (at treated sites) · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… · median 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Peto OR 4.77 [1.79, 12.71] | 4 studies · 137 participants | Low |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Mesiodistal movement of the upper first permanent molar · Patients of any age undergoing orthodontic treatment with fixed appliances and requiring anchorage (adolescents to… · End of anchorage reinforcement / space closure Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | MD -1.68 [-2.27, -1.09] | 7 studies · 308 participants | Moderate |
ITI SLA titanium screws vs Southern blasted/etched titanium screws Marginal bone level change · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 10 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | MD -0.02 [-0.18, 0.14] | 1 study · 24 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Success or failure of the anchorage device · Patients of any age undergoing orthodontic treatment with fixed appliances and requiring anchorage (adolescents to… Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | Reported in 5 studies but not pooled due to variability in the definition of success and incomplete reporting. Success rates: mini-implants 71.43% (10/14) (Basha 2010); Orthosystem mid-palatal implant 91.30% (21/23) vs… | 5 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Pancreatic cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 2.13 [1.02, 4.47] | 6 studies · 2113 participants | Ungraded |
An intervention delivered at one time point vs The same intervention delivered at a different time point Outcome NR · Patients of any age in any setting requiring intervention for iatrogenic injury to the inferior alveolar or lingual… · < 3 months; ≤ 6 months; > 6 months Interventions for iatrogenic inferior alveolar and lingual nerve injury (2014) · Cochrane | Discussion / Methods: no trials addressed optimal timing; the planned timing subgroup analyses (< 3 months, ≤ 6 months, > 6 months) could not be undertaken. | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hip fracture · Adults (general population) · Population-based controls Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | log ratio of geometric mean -0.51 [-0.64, -0.38] | 9 studies · 1655 participants | Ungraded |
Removable appliance with palatal crib associated with high-pull chincup vs No treatment Expansion of the upper and lower jaw · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… · End of treatment (12 months) Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | Listed among the outcome measures evaluated by Almeida 2005. No separate width/expansion estimate is reported in the text; the review concluded the interventions produced no significant change in the skeletal maxillary… | 1 study | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Intraoperative or postoperative bleeding · Children and young people aged 17 years or younger having dental treatment (including extractions) under general… Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane | None of the studies reported on this outcome | 0 studies | No studies |
NobelActive external connection implants vs NobelReplace implants Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 3 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.67 [0.17, 2.67] | 1 study · 106 participants | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Physiological parameters (cardiac/respiratory events; type and volume of GA drug) · Children and young people aged 17 years or younger having dental treatment (including extractions) under general… Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane | None of the studies reported on this outcome | 0 studies | No studies |
Branemark Mark IV TiUnite titanium screws vs Southern regular titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 year Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.57 [0.20, 1.63] | 1 study · 38 participants | Ungraded |
ITI SLA titanium implants vs SwissPlus (Zimmer) cylindrical implants Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 5 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | No failures at 5 years; risk ratio not estimable (Akoglu 2011) | 1 study | Ungraded |
One-stage crestal-approach sinus lift with autogenous bone and 8 mm implants vs Lateral-window sinus lift with 50% autogenous bone/50% Bio-Oss and implants at least 10 mm long Implant failure · Patients with 3 to 6 mm of residual bone height at the sinus floor · 5 years after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 0.30 [0.03, 3.15] | 1 study · 40 participants | Ungraded |
Sucralfate suspension (topical) vs Placebo suspension Healing time · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · End of treatment (3 months) Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD -1.09 [-2.61, 0.43] | 1 study · 30 participants | Ungraded |
Topical local anaesthetic (spray or dental swab) vs Placebo or no treatment Postoperative pain or distress · Children and young people aged 17 years or younger having dental treatment (including extractions) under general… · Postoperatively, typically up to discharge (5 to 60 minutes) Intraoperative local anaesthesia for reduction of postoperative pain following general anaesthesia for… (2014) · Cochrane | Because of substantial clinical and methodological heterogeneity in the studies, we were unable to determine an estimate of effect | 4 studies · 343 participants | Very low |
Powered toothbrush, counter oscillation action vs Manual toothbrush Plaque score (>3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Long term (>3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | MD -0.27 [-0.48, -0.07] | 2 studies · 69 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Difficulty speaking · Patients of any age in any setting requiring intervention for iatrogenic injury to the inferior alveolar or lingual… Interventions for iatrogenic inferior alveolar and lingual nerve injury (2014) · Cochrane | SoF row 'Difficulty speaking': This outcome was not reported in the included studies. | 0 studies | No studies |
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) Patient satisfaction (measured by patient satisfaction or aesthetic scales) · Adults (16 years or over) with one or more defective amalgam restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: amalgam (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
Sucralfate suspension (topical) vs Placebo suspension Number of episodes · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · End of treatment Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD 1.40 [-0.15, 2.95] | 1 study · 35 participants | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Augmentation procedure failure · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | One bilateral augmentation failure occurred in one trial only (Felice 2011). | 1 study | Ungraded |
Sucralfate suspension (topical) vs Placebo suspension Pain (0-3 scale) · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · End of treatment (3 months) Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD -0.38 [-0.87, 0.11] | 1 study · 30 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Non-Hodgkin's lymphoma · Adults (general population) · Females Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.81 [0.39, 1.70] | 4 studies · 39 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hypertension · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.70 [0.58, 0.86] | 7 studies · 48633 participants | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Patient satisfaction · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | Outcome proposed in the review but not found in any included study. The review states: 'The other outcomes proposed in this review were not found: stability of anterior open bite correction; reduction of snoring; signs… | 0 studies | No studies |