Gap finder
Search review questions
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 25OHD concentration vs Lower circulating 25OHD concentration Aggressive prostate cancer · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.98 [0.84, 1.15] | 6 studies · 4524 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fasting glucose · Adults with diabetes · Diabetes patients with normal glucose tolerance Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.01 [-0.21, 0.23] | NR | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Treatment costs · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Treatment costs: no trials reported this outcome (extrapolated by the review authors). Additional costs were associated with the long-implant + augmentation group (extra surgery, biomaterial, barrier, hospitalisation… | 0 studies | No studies |
Systemic interventions (aciclovir, thalidomide, corticosteroids, rebamipide, etanercept, colchicine, interferon-alpha) 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 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 |
Resorbable barrier (membrane) to seal the lateral window vs No membrane to seal the lateral window Implant 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 | OR 2.63 [0.75, 9.14] | 1 study · 104 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) Presence of clinical symptoms (pain, swelling, diagnosis of pulpitis, abscess formation) · 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 |
ITI SLA titanium screws vs Southern blasted/etched titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 10 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | No failures at 10 years; risk ratio not estimable (Payne 2003, Table 4) | 1 study · 24 participants | Ungraded |
Sucralfate suspension (topical) vs Placebo suspension Mean duration 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 -1.00 [-5.69, 3.69] | 1 study · 35 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Economic factors · 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 | Economic factors were not reported in any of the studies comparing two types of surgical anchorage | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Type 2 diabetes · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.63 [0.56, 0.69] | 16 studies · 72204 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Patient-reported altered sensation (spontaneous or evoked: anaesthesia/paraesthesia/dysaesthesia/hyperalgesia/allodynia) · Patients of any age in any setting requiring intervention for iatrogenic injury to the inferior alveolar or lingual… · Lip Interventions for iatrogenic inferior alveolar and lingual nerve injury (2014) · Cochrane | MD 21.79 [5.29, 38.29] | 1 study · 13 participants | Very low |
One-stage lateral sinus lift with monocortical autogenous bone blocks (iliac crest) vs Two-stage lateral sinus lift with autogenous particulate bone (iliac crest) Complications (sinus membrane perforation) · Patients with 2 to 7 mm of residual alveolar bone height in the edentulous maxillary sinus floor · 3 years after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 0.82 [0.24, 2.84] | 1 study · 40 participants | Ungraded |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Somatosensory evoked potentials · 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 ... somatosensory evoked potentials ...'. Not reported by the included trials. | 0 studies | No studies |
Early loading of mini-screw implant vs Delayed loading of mini-screw implant Success of the anchorage device · 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 | RR 1.00 [0.83, 1.20] | 2 studies · 36 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of hypercalcaemia · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 3.80 [0.90, 16.12] | 5 studies · 382 participants | Ungraded |
Bone substitute (anorganic bovine bone / Bio-Oss) vs A different bone substitute Augmentation procedure 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 | Augmentation procedure failure 0/11 versus 0/11; none. | 1 study · 11 participants | Ungraded |
Interferon-alpha (topical lozenges, 1000 IU or 2000 IU) vs Placebo Total ulcer burden · 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 | Kilic 2009 (interferon-alpha lozenges 1000 IU or 2000 IU vs placebo, 84 patients; high risk of selective reporting): the data presented did not allow analysis; authors reported no statistically significant difference… | 1 study · 84 participants | Ungraded |
Interferon-alpha (topical lozenges) vs Placebo Quality of life · 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 | Kilic 2009 described the use of a quality of life assessment tool but did not report any quality of life data. | 1 study · 84 participants | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Reduction or treatment of obstructive sleep apnoea syndrome (OSAS) or upper airway resistance syndrome (UARS) · 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 |
NobelActive external connection implants vs NobelActive internal 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 0.30 [-0.17, 0.77] | 1 study · 97 participants | Ungraded |
IMZ TPS titanium cylinders vs ITI TPS hollow titanium screws Implant failure · 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 | RR 2.90 [0.12, 68.50] | 1 study · 59 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in femoral neck · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 1.10 [0.40, 1.90] | 8 studies | Ungraded |
Systemic interventions (aciclovir, thalidomide, corticosteroids, rebamipide, etanercept, colchicine, interferon-alpha) vs Placebo Episode duration 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 |
Removable appliance with palatal crib associated with high-pull chincup vs No treatment Mandibular ramus growth · 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 | Cephalometric data (SNA, Co-A, SNB, Ar-Go, Ar.GoMe, Co-Gn, ANB) were reported to be not significantly different between groups; effects were dento-alveolar rather than skeletal. No pooled estimate (Almeida 2005). | 1 study | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in lumbar spine · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.10 [-0.60, 0.70] | 7 studies | Ungraded |
Osteotomes with mallet (Summers' technique) vs Rotary instruments (Cosci technique) Implant 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 (N = 12): no implant failures in either group. | 1 study · 12 participants | Ungraded |
Branemark turned titanium screws vs IMZ TPS titanium cylinders Implant failure · 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 | RR 1.00 [0.07, 15.26] | 1 study · 60 participants | Ungraded |
NobelReplace Select Tapered implants vs NobelReplace Groovy 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 3.00 [0.13, 70.92] | 1 study · 62 participants | Ungraded |
Autogenous bone graft (two-stage lateral sinus lift) vs Bone substitute (anorganic bovine bone / Bio-Oss) Complications · Patients with an atrophic posterior maxilla requiring maxillary sinus augmentation · up to 1 year Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 2.11 [0.18, 25.35] | 1 study · 40 participants | Ungraded |
Triamcinolone acetonide 0.1% ointment (topical) vs Phenytoin syrup mouthwash (30 mg in 5 mL) Positive response (not defined) · People with Behcet's disease with a history of recurrent oral aphthous-type (RAS-type) ulcers diagnosed clinically;… · 7 days Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | RR 1.63 [1.13, 2.34] | 1 study · 60 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Sporadic colorectal adenoma recurrence · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.87 [0.57, 1.33] | 3 studies · 1366 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Number of visits · 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 | No studies reported on the number of visits for the comparison of two types of surgical anchorage | 0 studies | No studies |
Rotary instruments to open the lateral sinus window vs Piezosurgery to open the lateral sinus window Complications at donor 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 | Rickert 2013 (N = 36): no complications at donor site. | 1 study · 36 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Residual overjet at the end of treatment · 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 | No studies reported on residual overjet at the end of treatment for the comparison of two types of surgical anchorage | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Ischaemic heart disease · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | HR 0.72 [0.65, 0.81] | 19 studies · 82982 participants | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Patient preference · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… · 4 to 5 months after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Felice 2009a: all patients expressed no preference (biased by design). Esposito 2012: five months after loading, 15 patients preferred short implants whereas 5 described both procedures as equally acceptable. | 2 studies | Ungraded |
Cyclosporin (systemic; 10 mg/kg/day) vs Colchicine (systemic; 1 mg daily) 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 | Masuda 1989: multiple adverse events in the cyclosporin arm; 3 patients withdrew and 9 had a dose reduction as a result. | 1 study · 92 participants | Ungraded |
Powered toothbrush, ionic 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 | MD -0.01 [-0.04, 0.02] | 2 studies · 116 participants | Ungraded |
Intraligamental injection local anaesthetic vs No treatment Postoperative anxiety · 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 | Anand 2005 used the Venham Picture Scale but, owing to the split-mouth design, postoperative anxiety could not be compared between the LA and no-treatment sides | 1 study | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures: non-vertebral · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.79 [0.63, 0.99] | 5 studies · 7130 participants | Ungraded |
Infiltration injection LA and intraligamental injection LA (3-arm) vs No treatment Postoperative pain or distress · Children and young people aged 17 years or younger having dental treatment (including extractions) under general… · Up to 30 minutes postoperatively; parent-reported to first night 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 | 1 study · 54 participants | Very low |
Intraligamental injection local anaesthetic 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 | Anand 2005: no signs of postoperative soft tissue trauma, 21 children reported numbness on the LA (experimental) side; Sammons 2007: no adverse events reported | 2 studies | Ungraded |
Powered toothbrush, ionic 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 | MD -0.36 [-0.59, -0.13] | 1 study · 64 participants | Ungraded |
Powered toothbrush (any mode of action) vs Manual toothbrush Dependability/reliability (mechanical failure) · Individuals of any age with no reported disability that might affect toothbrushing (including people wearing… Powered versus manual toothbrushing for oral health (2014) · Cochrane | Two trials reported mechanical failure of powered toothbrushes (1 of 48; 4 of 20). | 2 studies | Ungraded |
ITI SLA standard (regular neck) implants vs ITI SLActive 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 5.00 [0.26, 98.00] | 1 study · 40 participants | Ungraded |
Resorbable barrier (membrane) to seal the lateral window vs No membrane to seal the lateral window Prosthesis 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 | OR 2.63 [0.75, 9.14] | 1 study · 104 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Small for gestational age · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.54 [0.44, 0.67] | 6 studies · 6851 participants | Ungraded |
Higher circulating 1,25(OH)2D concentration vs Lower circulating 1,25(OH)2D concentration Prostate cancer · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.99 [0.87, 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 Breast cancer · Adults (general population) · Premenopausal Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.01 [0.97, 1.06] | 6 studies · 2890 participants | Ungraded |
Ankylos Plus (Dentsply) implants vs Seven (Sweden & Martina) 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 0.03 [-0.29, 0.35] | 1 study · 48 participants | Ungraded |