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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 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Aggressive prostate cancer · Adults (general population) 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 |
Astra TiO2-blasted titanium screws vs Branemark turned titanium screws Marginal bone level change · 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 | MD -0.09 [-0.33, 0.15] | 1 study · 65 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Cardiovascular disease mortality · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.55 [0.36, 0.85] | 5 studies · 24387 participants | Ungraded |
MegaGen EZ Plus blasted standard implants vs MegaGen EZ Plus calcium-incorporated (Xpeed) 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 0.04 [-0.13, 0.21] | 1 study · 60 participants | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Implant failure · 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 0.44 [0.10, 1.99] | 4 studies · 137 participants | Moderate |
Aciclovir (systemic; 800 mg 5x/day for 1 week then 400 mg 2x/day for 11 weeks) vs Placebo Frequency of 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 | Davies 1988 (aciclovir vs placebo, 36 patients, cross-over; high risk of reporting bias; concomitant treatments): data were not presented in a usable format; authors reported no statistically significant difference in… | 1 study · 36 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Birth length · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.19 [-0.26, 0.65] | 2 studies · 840 participants | Ungraded |
Interferon-alpha (topical; hydrogel or lozenges) 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 weeks (duration of treatment) Interventions for managing oral ulcers in Behçet's disease (2014) · Cochrane | MD 1.50 [-10.43, 13.43] | 1 study · 61 participants | 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 Partial graft loss · 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 0.63 [0.09, 4.24] | 1 study · 40 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Subperiosteal erosions · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.41 [0.07, 2.38] | 3 studies · 120 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Mortality · 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 1.40 [0.38, 5.15] | 4 studies · 381 participants | Ungraded |
Infiltration injection local anaesthetic vs No treatment or placebo Lip or cheek biting · 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 | Coulthard 2006: lip/cheek biting 3/70 (LA) vs 1/69 (placebo), P=0.62; Townsend 2009: 4/11 vs 1/12, P=0.16; no statistically significant difference | 2 studies · 162 participants | Ungraded |
Topical local anaesthetic (spray or dental swab) vs Placebo or 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 |
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration Colorectal cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 1.01 [0.59, 1.73] | 4 studies | Ungraded |
Dual mini-screw implant vs Single 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 1.01 [0.84, 1.22] | 1 study · 25 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) Success or failure of restoration (as defined by the USPHS criteria) · 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 |
One-stage lateral sinus lift with monocortical autogenous bone blocks (iliac crest) vs Two-stage lateral sinus lift with autogenous particulate bone (iliac crest) Implant failure · 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 1.56 [0.42, 5.76] | 1 study · 40 participants | Ungraded |
Powered toothbrush, circular 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 -0.02 [-0.37, 0.33] | 2 studies · 128 participants | Ungraded |
Topical local anaesthetic (spray or dental swab) vs Placebo or no treatment Lip or cheek biting · 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 lip or cheek biting | 0 studies | No studies |
Powered toothbrush (any mode of action) vs Manual toothbrush Staining · 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 no difference in tooth staining between manual and powered brushes. | 3 studies | Ungraded |
Powered toothbrush, side-to-side 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 0.10 [-0.14, 0.34] | 3 studies · 272 participants | Ungraded |
Cyclosporin A in orabase (topical) vs Placebo (orabase) 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 | Ergun 1997: no adverse effects were seen. | 1 study · 24 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Cardiovascular disease (prevalent) · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.67 [0.55, 0.82] | 16 studies · 64722 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Small for gestational age · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.67 [0.40, 1.11] | 2 studies · 305 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Creatinine clearance · 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 -1.68 [-6.92, 3.56] | 4 studies | Ungraded |
Interferon-alpha (systemic; 6 x 10^6 IU subcutaneously 3x/week for 3 months) vs Placebo (subcutaneous) Duration and pain of oral ulceration · 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 (subcutaneous interferon-alpha 6 x 10^6 IU 3x/week for 3 months vs placebo, 50 patients; high risk of reporting bias): data were not presented in a usable format; authors reported a statistically… | 1 study · 50 participants | Ungraded |
Branemark Mark III turned titanium implants vs Branemark Mark III TiUnite oxidised 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 | No failures (Froberg 2006, Table 1); risk ratio not estimable | 1 study · 15 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of hyperphosphataemia · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.57 [0.97, 2.54] | 2 studies · 59 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Fractures · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.00 [0.06, 15.41] | 4 studies | 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) · Postmenopausal Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.99 [0.97, 1.01] | 9 studies · 8766 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) Adverse events · 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 |
Branemark Mark IV turned titanium implants vs Branemark Mark IV TiUnite oxidised 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 0.33 [0.82, 7.32] | 1 study · 20 participants | Ungraded |
Powered toothbrush, ultrasonic 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 -0.99 [-1.21, -0.76] | 5 studies · 354 participants | Ungraded |
Branemark Mark IV turned titanium implants vs Branemark Mark IV TiUnite oxidised implants Marginal bone level change · 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 | MD 0.11 [-0.38, 0.60] | 1 study · 20 participants | Ungraded |
ITI SLActive titanium grade 4 implants vs ITI SLActive titanium-13zirconium (Roxolid) 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 2.00 [0.18, 21.66] | 1 study · 178 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of hypercalcaemia · 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 3.04 [1.17, 7.90] | 7 studies · 612 participants | Ungraded |
Infiltration injection local anaesthetic vs No treatment or placebo 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 |
Powered toothbrush, side-to-side 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 -0.27 [-0.77, 0.23] | 7 studies · 570 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in forearm · Children Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD 0.04 [-0.36, 0.45] | 3 studies | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Failure to correct the anterior open bite (open bite not closed) · 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 | RR 0.02 [0.00, 0.38] | 1 study · 40 participants | Ungraded |
Powered toothbrush, unknown/other 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 | Unknown/other action vs manual, gingivitis at >3 months: 1 trial; totals not selected. | 1 study | Ungraded |
Frankel's function regulator-4 (FR-4) with lip-seal training vs No treatment Signs and symptoms of atypical swallowing and speech production disturbances · 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 |
Osteotomes with mallet (Summers' technique) vs Rotary instruments (Cosci technique) Patient preference · Patients undergoing crestal maxillary sinus lift · 5 months after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Five months after loading, 13 of 15 patients preferred the side treated with the Cosci (rotary) technique; binomial test P = 0.007 (significant). Basis for the review's low-quality-evidence statement that patients may… | 1 study · 15 participants | Ungraded |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Tuberculosis · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD (to OR) 0.29 [0.19, 0.46] | 7 studies · 534 participants | Ungraded |
Rotary instruments to open the lateral sinus window vs Piezosurgery to open the lateral sinus 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 | Rickert 2013 (split-mouth, N = 36): no prosthesis failures in either group. | 1 study · 36 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… · Chin Interventions for iatrogenic inferior alveolar and lingual nerve injury (2014) · Cochrane | MD 8.40 [3.67, 13.13] | 1 study · 13 participants | Very low |
Low-level laser therapy (photon-plus GaAlAs diode laser; 70 mW output, continuous 820 nm) vs Placebo (sham) laser therapy Difficulty eating · 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 eating': This outcome was not reported in the included studies. | 0 studies | No studies |
Powered toothbrush, counter 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 0.01 [-0.30, 0.31] | 4 studies · 172 participants | Ungraded |
Implantium microthreads at the coronal top vs Implantium microthreads 0.5 mm below the top 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 | No failures; risk ratio not estimable (Song 2009) | 1 study · 20 participants | Ungraded |
Intraligamental injection local anaesthetic 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 |