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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.
75,239 questions in 5,342 reviews
current versionsNo studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%
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 |
|---|---|---|---|
Brushing vs Effervescent tablets Visual plaque score · American complete denture (CD) wearers · 12 weeks Interventions for cleaning dentures in adults (2009) · Cochrane | Tarbet 1984 compared brushing with two types of effervescent tablets. No standard deviations were reported and therefore no data were entered for this outcome. Brushing was associated with significantly lower plaque… | 1 study · 75 participants | Ungraded |
Inlay autogenous bone graft (iliac crest) vs Inlay bone substitute (Bio-Oss block) Major complications · Patients with atrophic posterior mandibles (5 to 7 mm above the mandibular canal) needing implants · Up to 1 year post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 2.00 [0.11, 37.83] | 1 study · 10 participants | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) Change in gingival recession (REC) · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | MD 0.02 [-0.3, 0.3] | 6 studies · 302 participants | Low |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) Change in marginal (radiographic) bone level · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | No statistically significant difference between EMD and control for radiographic bone gain (three trials; P effect = 0.27, I2 = 78%). | 3 studies | Ungraded |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Proximal contact at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Proximal contact at 6 months: odds ratio not estimable - no events recorded at the 6-month evaluation. | 1 study · 22 participants | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) Change in probing attachment level (PAL) · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | No statistically significant differences (one trial, Leknes 2009). | 1 study | Ungraded |
Enzyme cleanser vs Placebo / sham solution Microbial counts (hyphae and bacteria) · Institutionalised elderly wearing maxillary complete dentures (CD) · 12 weeks Interventions for cleaning dentures in adults (2009) · Cochrane | Lower hyphal and bacterial scores were also found for 'E' when compared with 'Plac' after 12 weeks. It was not possible to extract adequate data as the investigators did not provide standard deviations. | 1 study | Ungraded |
Arthrocentesis and lavage vs Arthroscopy Overall success (compound score combining pain and MIO) · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… · 6 to 24 months Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | RR 0.92 [0.56, 1.49] | 1 study · 19 participants | Ungraded |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both Adverse effects (insufficient fixation; re-operation/revision; plate exposure; superficial or deep wound infection; sinus tract; wound dehiscence; giant cell/foreign body or inflammatory reaction; post-traumatic dystrophy) · Participants over 18 years of age with fractures of the facial skeleton including the mandible, maxilla, zygoma… · Up to 3 years postoperatively Resorbable versus titanium plates for facial fractures (2009) · Cochrane | Planned adverse-effects outcome not assessed: none of the retrieved studies met the inclusion criteria, so no data were available for analysis. Verbatim (Effects of interventions): "Although 53 studies were retrieved… | 0 studies | No studies |
Prophylactic valaciclovir (lower dose) vs Prophylactic valaciclovir (higher dose) Viral isolates · Patients being treated for cancer (acute leukaemia; chemotherapy or stem-cell transplantation) Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane | Orlowski 2004: 182 throat swabs performed for patients receiving 500 mg of valaciclovir (n = 40) and 198 swabs for those receiving 1000 mg (n = 41); all of the cultures proved negative (1 trial, 81; not estimable). | 1 study · 81 participants | Ungraded |
Vertical distraction osteogenesis vs Autogenous onlay bone graft (mandibular ramus) 3-year post-loading bone level changes · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · 3 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.29 [-0.14, 0.72] | 1 study · 17 participants | Ungraded |
Prophylactic aciclovir (oral or intravenous) vs Prophylactic valaciclovir (oral) Presence/absence of HSV oral lesions · Patients being treated for cancer (predominantly haematological malignancies) Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane | RR 0.78 [0.26, 2.38] | 2 studies · 181 participants | Ungraded |
Enzyme cleanser vs Brushing Denture plaque coverage score · Wearers of maxillary and mandibular complete dentures (CD) Interventions for cleaning dentures in adults (2009) · Cochrane | Standard deviations were not reported for the relevant data so these were not included in the analysis. Reduction of plaque scores was associated with enzyme concentration (ANOVA, P < 0.001). Brushing alone and… | 1 study | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers Change in probing pocket depth (PPD) · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | MD -0.4 [-1.1, 0.2] | 6 studies · 304 participants | Low |
Autogenous bone block from the chin + resorbable barrier vs 100% Bio-Oss + resorbable barrier Prosthesis/implant failure (1 year) · Patients with horizontally resorbed maxillary sites needing single implants · Up to 1 year post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 0.19 [0.01, 4.07] | 1 study · 62 participants | Ungraded |
Any denture cleansing method (mechanical or chemical) vs Another method, sham/placebo, or no treatment Adverse effects · Adults (over 18) wearing complete dentures (CD) or removable partial dentures (RPD) Interventions for cleaning dentures in adults (2009) · Cochrane | Noticeable absence of reports about adverse effects; no included study assessed the extent of adverse effects (for example the aftertaste of sodium hypochlorite, or mechanical or chemical damage to denture materials)… | 0 studies | No studies |
Silicone surfactant cleanser vs Placebo / sham solution Visual plaque score · Complete denture (CD) wearers · 14 days Interventions for cleaning dentures in adults (2009) · Cochrane | MD -0.88 [-1.00, -0.76] | 1 study | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers Change in gingival recession (REC) · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | MD 0.41 [0.15, 0.66] | 5 studies · 206 participants | Low |
Vertical GBR with non-resorbable titanium-reinforced barriers vs Vertical GBR with resorbable barriers supported by osteosynthesis plates Complication at augmented site · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · About 4.5 months Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 1.46 [0.26, 8.05] | 1 study · 22 participants | Ungraded |
Association of brushing and effervescent tablets vs No treatment Fusobacteria (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD -3.75 [-4.16, -3.34] | 1 study · 18 participants | Ungraded |
Inlay/interposed bone graft (iliac or Bio-Oss block) + longer implants (vertical augmentation) vs Short implants (8 to 11 mm) without augmentation No improvement of facial appearance (3 weeks) · Patients with atrophic (resorbed) mandibles (anterior 6 to 12 mm; posterior 7 to 8 mm) needing implants · 3 weeks post-surgery Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 0.11 [0.03, 0.46] | 1 study · 40 participants | Ungraded |
Dental fillings (restorations) vs Dental extractions Outcome NR · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · Minimum 6 months follow-up Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | "No studies were found that compared restorations versus extractions or no treatment as an intervention in children with caries in the primary dentition." | NR | No studies |
Horizontal bone augmentation (any technique) vs No augmentation Outcome NR · Patients with horizontally resorbed maxillary sites needing single implants · At least to abutment connection (planned) Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | No trial evaluated whether horizontal bone augmentation is necessary (explicit gap) | 0 studies | No studies |
Arthrocentesis and lavage vs Arthroscopy Temporomandibular joint tenderness · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | To date, no randomised controlled trial in this area reported temporomandibular joint tenderness. | 0 studies | No studies |
Prophylactic aciclovir (oral or intravenous) vs Placebo Presence/absence of HSV oral lesions · Patients being treated for cancer (predominantly haematological malignancies) Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane | RR 0.16 [0.08, 0.31] | 9 studies · 398 participants | Ungraded |
Inlay/interposed bone graft (iliac or Bio-Oss block) + longer implants (vertical augmentation) vs Short implants (8 to 11 mm) without augmentation Prosthetic failure · Patients with atrophic (resorbed) mandibles (anterior 6 to 12 mm; posterior 7 to 8 mm) needing implants · Up to 2 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 3.20 [0.48, 21.25] | 2 studies · 98 participants | Ungraded |
Enzyme cleanser vs Placebo / sham solution Improvement on denture cleanliness (caregivers' opinion) · Institutionalised elderly wearing maxillary complete dentures (CD) · 12 weeks Interventions for cleaning dentures in adults (2009) · Cochrane | After 12 weeks using an enzyme denture cleanser ('E'), 8 of 18 caregivers perceived some improvement in CD cleanliness. After using a placebo solution ('Plac'), only 2 of 17 perceived some improvement (Analysis 1.1,… | 1 study · 35 participants | Ungraded |
Arthrocentesis and lavage vs Arthroscopy Quality of life · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | No data about quality of life were reported by the included trials. | 0 studies | No studies |
Ultrasound during vertical distraction osteogenesis vs Placebo (no ultrasound) during vertical distraction Distraction distance (bone gain, mm) · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · 2 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | Distraction distance 4.6 mm (ultrasound) vs 5.8 mm (placebo); difference 1.2 mm not statistically significant, in favour of placebo; data not shown (Schortinghuis 2008) | 1 study · 9 participants | Ungraded |
Arthrocentesis and lavage vs Arthroscopy Deviation of the mandible · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | To date, no randomised controlled trial in this area reported deviation of the mandible. | 0 studies | No studies |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Marginal integrity at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Marginal integrity at 6 months: odds ratio not estimable - no events recorded at the 6-month evaluation. | 1 study · 22 participants | Ungraded |
Effervescent tablets vs Association of brushing and effervescent tablets Total anaerobes (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD 1.20 [-0.08, 2.48] | 1 study · 18 participants | Ungraded |
Prophylactic aciclovir (oral or intravenous) vs Placebo Days stay in hospital · Patients being treated for cancer (predominantly haematological malignancies) Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane | For prevention or treatment, no trials reported on duration of hospital stay, amount of analgesia or patient quality of life. | 0 studies | No studies |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) Change in probing pocket depth (PPD) · Patients affected by chronic, aggressive, or early onset periodontitis, with intrabony defects having an intrabony… · 1 year (time-points 1, 5 and 10 years planned) Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects (2009) · Cochrane | MD 0.88 [0.44, 1.31] | 9 studies · 371 participants | Low |
Vertical distraction osteogenesis vs Autogenous inlay bone graft (iliac crest) Vertical bone gain · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · At least 1.5 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 3.25 [1.66, 4.84] | 1 study · 11 participants | Ungraded |
Vertical GBR with non-resorbable titanium-reinforced barriers vs Vertical GBR with resorbable barriers supported by osteosynthesis plates Augmentation procedure failure · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · About 4.5 months Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 2.22 [0.17, 28.86] | 1 study · 22 participants | Ungraded |
Enzyme cleanser vs Placebo / sham solution Denture plaque (biofilm) score · Institutionalised elderly wearing maxillary complete dentures (CD) · 5 weeks; 3 months Interventions for cleaning dentures in adults (2009) · Cochrane | Both interventions reduced biofilm scores after 2 weeks. However, plaque scores were significantly lower for 'E' after 5 weeks (P < 0.05) and 3 months (P < 0.01), as assessed by Chi2 test. It was not possible to… | 1 study | Ungraded |
Inlay/interposed bone graft (iliac or Bio-Oss block) + longer implants (vertical augmentation) vs Short implants (8 to 11 mm) without augmentation Major complications · Patients with atrophic (resorbed) mandibles (anterior 6 to 12 mm; posterior 7 to 8 mm) needing implants · Up to 2 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 4.97 [1.10, 22.40] | 2 studies · 100 participants | Ungraded |
1-stage (non-submerged) implant placement vs 2-stage (submerged) implant placement Patient preference including aesthetics (split-mouth studies only) · Any subject receiving osseointegrated dental implants · 6 to 12 months after loading Interventions for replacing missing teeth: 1- versus 2-stage implant placement (2009) · Cochrane | Planned outcome (patient preference including aesthetics, only in split-mouth studies); no included trial reported it. | 0 studies | No studies |
Vertical GBR with non-resorbable titanium-reinforced barriers vs Vertical GBR with resorbable barriers supported by osteosynthesis plates Perimplant bone loss (3 years) · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · 3 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.02 [-0.50, 0.54] | 1 study · 22 participants | Ungraded |
Arthrocentesis and lavage vs Arthroscopy Pain (VAS) · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… · 24 months Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | MD -1.00 [-2.12, 0.12] | 1 study · 62 participants | Ungraded |
Autogenous inlay bone graft (iliac crest) vs Autogenous onlay bone graft (iliac crest) Major complications · Patients with deficient posterior mandibles (4.5 to 10 mm above the mandibular canal) needing implants · Up to 1 year post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 1.07 [0.20, 5.77] | 1 study · 23 participants | Ungraded |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both Patient satisfaction (questionnaire) · Participants over 18 years of age with fractures of the facial skeleton including the mandible, maxilla, zygoma… · Up to 3 years postoperatively Resorbable versus titanium plates for facial fractures (2009) · Cochrane | Planned secondary outcome not assessed: none of the retrieved studies met the inclusion criteria, so no data were available for analysis. Verbatim (Effects of interventions): "Although 53 studies were retrieved in our… | 0 studies | No studies |
Vertical GBR with non-resorbable titanium-reinforced barriers vs Vertical GBR with resorbable barriers supported by osteosynthesis plates Vertical bone gain · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · About 4.5 months Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.32 [-0.79, 1.43] | 1 study · 22 participants | Ungraded |
Autogenous inlay bone graft (iliac crest) vs Autogenous onlay bone graft (iliac crest) Vertical bone gain · Patients with deficient posterior mandibles (4.5 to 10 mm above the mandibular canal) needing implants · Up to 1 year post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.97 [-0.07, 2.01] | 1 study · 23 participants | Ungraded |
1-stage (non-submerged) implant placement vs 2-stage (submerged) implant placement Radiographic marginal bone level changes · Any subject receiving osseointegrated dental implants · 6 to 12 months after loading Interventions for replacing missing teeth: 1- versus 2-stage implant placement (2009) · Cochrane | MD -0.10 [-0.40, 0.20] | 1 study · 29 participants | Ungraded |
Arthrocentesis and lavage vs Arthroscopy Muscular tenderness · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | To date, no randomised controlled trial in this area reported muscular tenderness. | 0 studies | No studies |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both Direct costs (plates, supporting equipment, hospital bed days, retreatment) · Participants over 18 years of age with fractures of the facial skeleton including the mandible, maxilla, zygoma… · Up to 3 years postoperatively Resorbable versus titanium plates for facial fractures (2009) · Cochrane | Planned cost outcome not assessed: none of the retrieved studies met the inclusion criteria, so no data were available for analysis. Verbatim (Effects of interventions): "Although 53 studies were retrieved in our… | 0 studies | No studies |
1-stage (non-submerged) implant placement vs 2-stage (submerged) implant placement Implant failure · Any subject receiving osseointegrated dental implants · 6 to 12 months after loading Interventions for replacing missing teeth: 1- versus 2-stage implant placement (2009) · Cochrane | RR 1.39 [0.59, 3.27] | 4 studies · 230 participants | Moderate |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both Analgesic medication used (type, dose, frequency) · Participants over 18 years of age with fractures of the facial skeleton including the mandible, maxilla, zygoma… · Up to 3 years postoperatively Resorbable versus titanium plates for facial fractures (2009) · Cochrane | Planned primary outcome not assessed: none of the retrieved studies met the inclusion criteria, so no data were available for analysis. Verbatim (Effects of interventions): "Although 53 studies were retrieved in our… | 0 studies | No studies |