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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 |
|---|---|---|---|
Vitamin D supplementation vs Placebo or control Preterm delivery · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.77 [0.35, 1.66] | 2 studies · 529 participants | Ungraded |
Powered toothbrush (any mode of 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 -0.43 [-0.60, -0.25] | 44 studies · 3345 participants | Moderate |
Dual mini-screw implant vs Single mini-screw implant Duration of space closure · 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 | MD -2.19 [-6.35, 1.97] | 1 study · 25 participants | Ungraded |
NobelActive internal connection implants vs NobelReplace 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 0.30 [-0.17, 0.77] | 1 study · 97 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Birth weight · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 130.9 [75.1, 186.7] | 4 studies · 5541 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures: vertebral or deformity · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.90 [0.42, 1.92] | 5 studies · 9138 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Mechanosensory perception (load in grams to elicit sensation; Semmes Weinstein monofilaments) · 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 | MD 1.07 [0.17, 1.97] | 2 studies · 26 participants | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Parental 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 | No study reported parental satisfaction | 0 studies | No studies |
Psychological / counselling interventions (counselling, acupuncture, cognitive behavioural therapy, relaxation therapy, behaviour modification, electromyographic biofeedback, hypnosis, re-education) vs Another intervention, or no intervention Outcome NR · 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 evaluated ... psychological interventions.' No eligible RCT of psychological / counselling interventions (CBT, relaxation, behaviour modification, biofeedback, hypnosis, re-education, acupuncture). | 0 studies | No studies |
Infiltration injection local anaesthetic vs No treatment or placebo 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 | None of the studies reported on patient or child satisfaction | 0 studies | No studies |
Hand mallet (osteotomes) vs Electric mallet Implant failure · Patients undergoing one-stage crestal maxillary sinus lift without bone grafts (baseline residual bone height about… · before loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 1.00 [0.06, 16.56] | 1 study · 80 participants | Ungraded |
Topical local anaesthetic (spray or dental swab) vs Placebo or 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 | Elhakim 1993 reported prolonged postoperative bleeding in the no-treatment group; Andrzejowski 2002 reported no difference in bleeding (nurse-assessed 'mild' in both groups) | 2 studies · 160 participants | Very low |
Vitamin D supplementation vs Control Bone mineral density in forearm · 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 |
Rebamipide (systemic; 300 mg daily) vs Placebo Global aphthae count and pain score · 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 | Matsuda 2003 (rebamipide 300 mg daily vs placebo, 35 patients; high risk of reporting bias; concomitant treatments): authors stated that rebamipide improved the global evaluation aphthae count and global evaluation… | 1 study · 35 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Ovarian cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.83 [0.63, 1.09] | 10 studies · 2489 participants | Ungraded |
Etanercept (systemic; 25 mg subcutaneously twice weekly for 4 weeks) vs Placebo (subcutaneous) Mean number of 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 | Melikoglu 2005 (etanercept 25 mg s.c. twice weekly for 4 weeks vs placebo, 40 male patients; high risk of reporting bias): authors reported a statistically significant difference in mean number of oral ulcers with… | 1 study · 40 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Stroke · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.61 [0.50, 0.75] | 7 studies · 39095 participants | Ungraded |
Topical interventions (sucralfate, interferon-alpha, cyclosporin A) vs Placebo Episode frequency 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 (topical interventions vs placebo), grouped comment spanning all four listed outcomes (verbatim): "5 placebo-controlled trials evaluated topical interventions (sucralfate suspension (2 trials), interferon-alpha (2… | NR | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Signs and symptoms of respiratory disease (mouth breathing, nasal airway resistance) · 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 |
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 Prosthesis 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 0.47 [0.04, 5.69] | 1 study · 40 participants | Ungraded |
Infiltration injection local anaesthetic vs No treatment or placebo 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 | Because of substantial clinical and methodological heterogeneity in the studies, we were unable to determine an estimate of effect | 2 studies · 174 participants | Very low |
Vitamin D supplementation vs Placebo or control Fasting glucose · Adults with diabetes · Diabetes patients with abnormal glucose tolerance Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -0.3 [-0.9, 0.3] | NR | Ungraded |
Topical interventions (sucralfate, interferon-alpha, cyclosporin A) vs Placebo 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 | SoF (topical interventions vs placebo), grouped comment spanning all four listed outcomes (verbatim): "5 placebo-controlled trials evaluated topical interventions (sucralfate suspension (2 trials), interferon-alpha (2… | NR | Ungraded |
Powered toothbrush, unknown/other 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 | Unknown/other action vs manual, gingivitis at 1 to 3 months: 3 trials; totals not selected (data presented in forest plots but not pooled). | 3 studies | Ungraded |
Higher circulating 1,25(OH)2D concentration vs Lower circulating 1,25(OH)2D concentration Breast cancer · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.99 [0.68, 1.44] | 3 studies · 3627 participants | Ungraded |
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) Perioperative or postoperative pain or discomfort · 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 |
Sinus lift with bone graft (granular Bio-Oss) vs Sinus lift without bone graft (Inion resorbable rigid barrier maintaining space / no bone) Prosthesis 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 0.63 [0.10, 4.22] | 1 study · 44 participants | Ungraded |
Turned (smoother) implant surfaces vs Roughened implant surfaces Peri-implantitis · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 3 years, turned vs roughened surfaces Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.80 [0.67, 0.96] | 4 studies · 144 participants | Low |
One active intervention (surgical, medical, or psychological) vs A different active intervention (direct head-to-head comparison) Outcome NR · 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 | Discussion: 'There is also a lack of trials directly comparing these methods ...'. No eligible RCT directly comparing different active interventions. | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Breast cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.55 [0.42, 0.71] | 21 studies · 26317 participants | Ungraded |
Interferon-alpha 1000 IU lozenges (topical) vs Interferon-alpha 2000 IU lozenges (topical) Total ulcer burden · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · Interferon-alpha dose comparison Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | Kilic 2009 (interferon-alpha 1000 IU vs 2000 IU lozenges, 84 patients): the data presented did not allow analysis; authors reported no statistically significant difference in total ulcer burden between the two doses. | 1 study · 84 participants | Ungraded |
NobelReplace Select Tapered implants vs NobelReplace Groovy 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 0.29 [-0.06, 0.64] | 1 study · 62 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Colon cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.78 [0.56, 1.07] | 10 studies · 4578 participants | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Residual overjet at the end of treatment · 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 | No studies reported on residual overjet at the end of treatment | 0 studies | No studies |
Vitamin D supplementation vs Placebo or control Total cholesterol · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 1.52 [-1.42, 4.46] | 11 studies | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Parathyroid hormone · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -196.05 [-298.43, -93.66] | 6 studies | Ungraded |
Rotary instruments to open the lateral sinus window vs Piezosurgery to open the lateral sinus window Augmentation procedure failure · Patients undergoing lateral-window maxillary sinus lift · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Rickert 2013 (N = 36): no augmentation procedure failures. | 1 study · 36 participants | Ungraded |
Repelling-magnet splints vs Bite-blocks Side effects / adverse effects (unilateral crossbite; transverse problems) · 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 | "After 4 months the open bite was observed to close in the magnet group, but in four out of these ten patients, transverse problems were observed (unilateral crossbite) which led to the interruption of the treatment… | 1 study · 10 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hip fracture · Adults (general population) · Hospital-based controls Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | log ratio of geometric mean -0.26 [-0.33, -0.23] | 8 studies · 2201 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of requiring dialysis · Adults with chronic kidney disease not requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.76 [0.36, 1.62] | 4 studies · 245 participants | Ungraded |
Thalidomide (systemic; 100 mg or 300 mg daily) vs Placebo 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;… · Males only Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | Hamuryudan 1998: significant adverse effects including severe sedation, polyneuropathy, loss of libido, and weight gain; a greater number of adverse events was seen for the higher (300 mg) dose; 4 patients withdrew due… | 1 study · 101 participants | Ungraded |
Repair of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) vs Replacement of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) Further restoration required (repair, restoration, placement of crown/inlay, root filling) · Adults (16 years or over) with one or more defective resin composite 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: resin composite (2014) · Cochrane | No randomised controlled trials were found | 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) Success or failure of restoration (as defined by the USPHS criteria) · 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 |
One-stage augmentation (implants placed simultaneously) vs Two-stage augmentation (delayed implant placement) Implant failure · Patients requiring maxillary sinus augmentation · 1 year after loading (before loading) Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 3.48 [0.34, 35.61] | 1 study · 58 participants | Ungraded |
NobelActive external connection implants vs NobelReplace 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 0.00 [-0.41, 0.41] | 1 study · 88 participants | Ungraded |
Powered toothbrush (any mode of action) vs Manual toothbrush Adverse events (soft tissue trauma) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… Powered versus manual toothbrushing for oral health (2014) · Cochrane | SoF 'Adverse events' row (narrative): There was no apparent relationship between the use of powered toothbrushes and soft tissue trauma. In part this finding was due to the very small number of adverse events reported… | 40 studies | Ungraded |
Surgical anchorage (mini-screw or mid-palatal implant) vs Conventional anchorage (headgear, transpalatal/palatal arch, etc.) Patient perception: discomfort · 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 2 studies (Chesterfield 2007, 47 patients; Feldmann 2007, 113 patients) on a VAS 0-100; discomfort most severe the evening after surgery (Nobel-Biocare onplant median 33, IQR 0-96) and after… | 2 studies · 160 participants | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Lip or cheek biting, numbness or allergy · 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 lip or cheek biting | 0 studies | No studies |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Position of the incisors (upper incisor inclination) · Children and adolescents (over 80% aged 16 years or younger at treatment start) with anterior open bite (lack of… · End of treatment (about 2 years) Orthodontic and orthopaedic treatment for anterior open bite in children (2014) · Cochrane | The angulation of the upper incisors with the palatal plane (1/ANSPNS) decreased on average 0.3 (SD 4.6) degrees in the control group, whereas in the treated group the mean retrusion was 4 (SD 4.6) degrees, P < 0.01.… | 1 study | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Colorectal cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.70 [0.58, 0.84] | 10 studies · 6712 participants | Ungraded |