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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 maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Gestational diabetes · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.67 [0.53, 0.85] | 10 studies · 4112 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.01 [0.93, 1.09] | 10 studies · 25016 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Quality of life · 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 | Results: 'No studies reported on quality of life ...'. Not reported by the included laser trials. | 0 studies | No studies |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Reduction of snoring · 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 |
Autogenous bone graft (two-stage lateral sinus lift) vs Bone substitute (anorganic bovine bone / Bio-Oss) Implant failure · Patients with an atrophic posterior maxilla requiring maxillary sinus augmentation · abutment connection to 1 year Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 4.20 [0.81, 21.79] | 2 studies · 51 participants | Ungraded |
Repelling-magnet splints vs Bite-blocks Anterior open bite correction · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… · About 4 months (treatment interrupted early) Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | Could not be analysed statistically. After 4 months the open bite was observed to close in the magnet group, but in four out of these ten patients transverse problems (unilateral crossbite) were observed, which led to… | 1 study | Ungraded |
NobelActive external connection implants vs NobelActive internal connection 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 1.06 [0.25, 4.51] | 1 study · 113 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in forearm · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -0.70 [-1.70, 0.40] | 2 studies | Ungraded |
Powered toothbrush, rotation oscillation action vs Manual toothbrush Gingivitis score (1 to 3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Short term (1 to 3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.49 [-0.73, -0.26] | 21 studies · 1479 participants | Ungraded |
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration Prostate cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.99 [0.87, 1.14] | 7 studies · 3640 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Kidney cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 1.01 [0.65, 1.58] | 6 studies · 1480 participants | Ungraded |
Bone graft with platelet-rich plasma (PRP) vs Bone graft without PRP Implant failure · 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 | No statistically significant difference for implant failures. Per trial: Raghoebar 2005 1 failure in the PRP arm, OR 3.67 (0.12 to 113.73), P = 0.46; Torres 2009 (PRP only = 1, no-PRP only = 2), OR 0.50 (0.01 to… | 2 studies · 62 participants | Ungraded |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Fractures · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD (to OR) 0.31 [0.23, 0.42] | 28 studies · 2956 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in hip · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.70 [-0.10, 1.60] | 6 studies | Ungraded |
NobelActive internal connection implants vs Nobel Speedy Groovy external connection 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 -0.59 [-0.74, -0.44] | 1 study · 34 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) · Males Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.65 [0.35, 1.23] | 6 studies · 65 participants | Ungraded |
Bone substitute (anorganic bovine bone / Bio-Oss) vs A different bone substitute Prosthesis failure · Patients undergoing two-stage maxillary sinus augmentation · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Lindgren 2012 (split-mouth, 11 patients): prosthesis failures 0/11 versus 0/11; none. | 1 study · 11 participants | Ungraded |
Sinus lift with bone graft (granular Bio-Oss) vs Sinus lift without bone graft (Inion resorbable rigid barrier maintaining space / no bone) Augmentation procedure failure · Patients with an atrophic maxillary sinus requiring augmentation (1 to 5 mm residual bone height) · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 0.48 [0.04, 5.67] | 1 study · 44 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Number of visits · 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 | MD 7.01 [3.47, 10.55] | 1 study · 47 participants | Ungraded |
Powered toothbrush (any mode of action) vs Manual toothbrush Plaque score (1 to 3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Short term (1 to 3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.50 [-0.70, -0.31] | 40 studies · 2871 participants | Moderate |
Thalidomide (systemic; 100 mg or 300 mg daily) vs Placebo Number of (minor aphthous) oral ulcers · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · Males only Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | Hamuryudan 1998 (thalidomide 100 mg or 300 mg daily vs placebo, 101 male patients; high risk of reporting bias): a significant effect on mean numbers of minor oral ulcers was reported from week 4 in both thalidomide… | 1 study · 101 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Parathyroidectomy · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.82 [0.05, 12.47] | 2 studies · 233 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Low density lipoprotein · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 3.23 [0.55, 5.9] | 7 studies | Ungraded |
Vitamin D supplementation vs Placebo or control Cardiovascular disease · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.95 [0.86, 1.05] | 2 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Body mass index · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | Z score -0.15 [-0.19, -0.11] | 37 studies · 16525 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in lumbar spine · Children Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD 0.15 [-0.01, 0.31] | 5 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Sporadic colorectal adenoma · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.82 [0.69, 0.97] | 9 studies · 6268 participants | Ungraded |
Rotary instruments to open the lateral sinus window vs Piezosurgery to open the lateral sinus window Complications at augmented site · Patients undergoing lateral-window maxillary sinus lift · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 1.00 [0.27, 3.74] | 1 study · 36 participants | Ungraded |
Powered toothbrush, ultrasonic 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 | Ultrasonic vs manual, plaque at >3 months: one trial (Terezhalmy 1995a); no statistically significant difference; totals not selected (no pooled estimate presented in this version). | 1 study · 46 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Adverse events · 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 'Adverse events': This outcome was not reported in the included studies. | 0 studies | No studies |
Vitamin D supplementation vs Placebo or control Fractures: hip · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.15 [0.99, 1.33] | 9 studies · 24749 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Patient acceptability · Patients undergoing orthodontic treatment requiring surgical (mini-screw implant) anchorage Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | Acceptability was not reported in any of the studies comparing two types of surgical anchorage | 0 studies | No studies |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Pain · 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 'Pain': This outcome was not reported in the included studies. | 0 studies | No studies |
Powered toothbrush, rotation oscillation action vs Manual toothbrush Plaque score (1 to 3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Short term (1 to 3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.53 [-0.74, -0.31] | 20 studies · 1404 participants | Ungraded |
Cyclosporin A in orabase (topical, 70 mg/g) vs Placebo (orabase) Oral ulcers (number, size, healing time) · 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 | Ergun 1997 (cyclosporin A in orabase vs placebo orabase, 24 patients; high risk of reporting bias): no data were presented; authors reported no clinical improvement in the number, size, and healing time of ulcers for… | 1 study · 24 participants | Ungraded |
Powered toothbrush, counter oscillation action vs Manual toothbrush Gingivitis 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 -0.19 [-0.66, 0.29] | 2 studies · 69 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Alkaline phosphatase · Adults with chronic kidney disease not requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -21.81 [-40.39, 3.22] | 2 studies | Ungraded |
Vitamin D supplementation vs Placebo or control Birth length · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.97 [-0.41, 2.34] | 2 studies | Ungraded |
NobelActive internal 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 0.90 [0.25, 3.15] | 1 study · 106 participants | Ungraded |
Powered toothbrush, ionic 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 -0.50 [-0.74, -0.26] | 1 study · 64 participants | Ungraded |
One-stage augmentation (implants placed simultaneously) vs Two-stage augmentation (delayed implant placement) Prosthesis failure · Patients requiring maxillary sinus augmentation · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 0.35 [0.01, 6.83] | 1 study · 58 participants | Ungraded |
Powered toothbrush, rotation oscillation action vs Manual toothbrush Gingivitis 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 -0.35 [-0.50, -0.20] | 8 studies · 684 participants | Ungraded |
Astra cylindrical turned surface implants vs Astra cylindrical TiO2-blasted surface 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 | Primary pairwise data unusable (implant numbers per surface not disclosed); one turned implant failed early. Data used only for the turned-vs-roughened secondary analysis (Wennstrom 2004) | 1 study · 51 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Patient perception: pain · 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) on a VAS 0-100; the first evening after the intervention pain was significantly higher for surgical group A (P=0.002) and conventional group C (P=0.007) than surgical… | 1 study · 113 participants | Ungraded |
Depot corticosteroids (systemic; 40 mg methylprednisolone IM every 3 weeks for 27 weeks) vs Placebo (saline IM injection) Mean number of oral ulcers · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · End of treatment (week 27) Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD 0.00 [-0.47, 0.47] | 1 study · 85 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Systolic blood pressure · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -2.39 [-5.7, 0.9] | 3 studies | Ungraded |
Pre-drilling mini-screw implant vs Self-drilling mini-screw implant Patient perception: pain · Patients undergoing orthodontic treatment requiring surgical (mini-screw implant) anchorage Reinforcement of anchorage during orthodontic brace treatment with implants or other surgical methods (2014) · Cochrane | Self-reported pain on insertion (0-4 scale): pre-drilling mean 0.73 (SD 1.1; median 0.00, IQR 0-3) vs self-drilling mean 1.87 (SD 1.13; median 2.0, IQR 0-4); 1 study (Lehnen 2011), 30 participants | 1 study · 30 participants | Ungraded |
Interferon-alpha (systemic) vs Placebo (subcutaneous) Safety of the intervention including adverse effects · 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 | Alpsoy 2002: high rate of adverse events including alopecia, leukopenia, and diarrhoea; 18 of 23 patients in the treatment arm experienced mild flu-like symptoms. | 1 study · 50 participants | Ungraded |
Powered toothbrush, circular action vs Manual toothbrush Gingivitis score (1 to 3 months) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… · Short term (1 to 3 months) Powered versus manual toothbrushing for oral health (2014) · Cochrane | SMD -0.18 [-0.53, 0.17] | 2 studies · 128 participants | Ungraded |
Cyclosporin (systemic; 10 mg/kg/day for 16 weeks) vs Colchicine (systemic; 1 mg daily) Alleviation of oral aphthous ulcers · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · 16 weeks Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | RR 3.3 [1.85, 5.88] | 1 study · 92 participants | Ungraded |