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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.

Limit to evidence status or GRADE (optional)

10,375 questions in 429 reviews · Oral Health

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 studyUngraded
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 participantsLow
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 participantsUngraded
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 studiesNo 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 studyUngraded
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 participantsLow
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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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."NRNo 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 studiesNo 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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 studiesNo 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 participantsLow
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 participantsUngraded
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 participantsUngraded
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 studyUngraded
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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesNo 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 participantsUngraded
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 participantsUngraded
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 participantsUngraded
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 studiesNo 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 studiesNo 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 participantsModerate
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 studiesNo studies
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both
Need for retreatment or replacement of fixation due to failure of the fixation · 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 studiesNo studies
Aciclovir (oral or intravenous) for treatment vs Placebo
Patient quality of life · Patients being treated for cancer with established oral HSV infection (bone marrow transplant recipients /…
Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane
For the treatment comparison (aciclovir versus placebo), no data were available for recurrence of lesions, amount of analgesia, days of stay in hospital, cost of oral care or patient quality of life.0 studiesNo studies
Brushing vs No treatment (immersion in distilled water)
Microbial counts (total aerobes, anaerobes, yeasts) · Complete denture (CD) wearers in a nursing home
Interventions for cleaning dentures in adults (2009) · Cochrane
Moore 1984 found that the seven tested methods were similar and resulted in a significant reduction in total aerobes and anaerobes compared with immersion in distilled water (paired t test, P < 0.05). Some chemical…1 study · 12 participantsUngraded
Vertical distraction osteogenesis vs Autogenous inlay bone graft (iliac crest)
Complications · 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
OR 7.50 [0.46, 122.70]1 study · 11 participantsUngraded
Prophylactic aciclovir (oral or intravenous) vs Placebo
Recurrence of 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
Recurrence of lesions was a planned secondary outcome; no included trial reported data for this outcome in the prophylactic aciclovir versus placebo comparison.0 studiesNo studies
Primary surgical intervention (curettage, peripheral osteotomy, or resection) vs Primary non-surgical intervention (intralesional corticosteroids, subcutaneous calcitonin, interferon alpha, or imatinib)
Adverse events · Patients with a pathological diagnosis of central giant cell granuloma (CGCG) of the jaws
Interventions for central giant cell granuloma (CGCG) of the jaws (2009) · Cochrane
no estimate extracted0 studiesNo studies
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD)
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
MD 1.08 [0.61, 1.55]9 studies · 371 participantsLow