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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first. Each row links to its question's own page, which gathers every review that asked it, however worded; see the questions asked by more than one review.
3,358 questions in 190 reviews · cluster CL0289
current versionsNo studies 599 · 17.8%Ungraded 1,759 · 52.4%Very low 612 · 18.2%Low 269 · 8%Moderate 107 · 3.2%High 12 · 0.4%
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.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
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 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 |
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 |
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 |
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 |
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 |
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 |
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 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 |
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 |
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 |
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 |
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 |
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 studies | No studies |
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 participants | Ungraded |
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 studies | No studies |
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 participants | Low |
Total anaerobes (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD -5.5 [-6.55, -4.45] | 1 study · 18 participants | Ungraded |
Tooth loss · 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 | SoF (Emdogain vs GTR): Tooth loss - See comment; too few teeth lost to undertake analysis. 237 participants (5 studies). No GRADE rating given. | 5 studies · 237 participants | Ungraded |
Implant 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 5.74 [0.92, 35.82] | 2 studies · 98 participants | Ungraded |
Any chronic or lasting pain measured using any validated scale after 3 weeks · Participants over 18 years of age with fractures of the facial skeleton including the mandible, maxilla, zygoma… · After 3 weeks 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 |
Maximum bite force · 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 maximum bite force. | 0 studies | No studies |
Vertical bone gain · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · Up to 3 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.30 [-0.97, 1.57] | 1 study · 17 participants | Ungraded |
Complete remission · 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 extracted | 0 studies | No studies |
Tooth loss · 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 | SoF (Emdogain vs Control): Tooth loss - See comment / See comment; too few teeth lost to undertake analysis. 371 participants (9 studies). No GRADE rating given. | 9 studies · 371 participants | Ungraded |
Status of occlusion (e.g. Angle's classification, ANB, Wits analysis) · 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 |
Any denture cleansing method (mechanical or chemical) vs Another method, sham/placebo, or no treatment Outcome NR · Wearers of removable partial dentures (RPD), over the age of 18 Interventions for cleaning dentures in adults (2009) · Cochrane | No included study assessed removable partial denture (RPD) wearers; all six included trials assessed complete denture wearers (Discussion; Implications for research: 'No included study assessed removable partial… | 0 studies | No studies |
Radiolucencies on bitewing X-rays at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 4.53 [0.83, 24.65] | 1 study · 48 participants | Ungraded |
Complication at augmented + donor site · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · Up to 3 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 0.5 [0.07, 3.55] | 1 study · 17 participants | Ungraded |
Prosthesis failure · 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 1.0 [0.01, 82.26] | 1 study · 10 participants | Ungraded |
Complications (biological and biomechanical) · 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 0.13 [0.01, 2.25] | 1 study · 30 participants | Ungraded |
Fusobacteria (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD 0.04 [-0.33, 0.41] | 1 study · 18 participants | Ungraded |
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 -0.2 [-0.55, 0.20] | 6 studies · 304 participants | Low |
Maximum incisal (mouth) opening (MIO) · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… · 6 to 24 months (Fridrich); 12 months (Goudot) Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | MD -5.28 [-7.10, -3.46] | 2 studies · 81 participants | Ungraded |
Aesthetics · 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 | SoF (Emdogain vs GTR): Aesthetics - See comment; 0 [0]; No studies reported this. | 0 studies | No studies |
Vertical bone gain · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · Up to 1 year post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | MD 0.6 [0.21, 0.99] | 1 study · 5 participants | Ungraded |
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 |
Visual plaque score · Complete denture (CD) wearers · 2 days Interventions for cleaning dentures in adults (2009) · Cochrane | MD -1.02 [-1.13, -0.91] | 1 study | Ungraded |
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 | No statistically significant differences (one trial, Leknes 2009). | 1 study | Ungraded |
Implant/prosthesis failure and complications · Patients with resorbed maxillae (incl. atrophic sinuses) needing implants · 2 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | No statistically significant difference for any outcome; data not shown (Raghoebar 2006) | 1 study · 8 participants | Ungraded |
Tooth loss · 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 teeth were lost in either group. | 1 study | Ungraded |
Ultrasonic treatment or microwave disinfection device vs Another method, sham/placebo, or no treatment Outcome NR · Adults (over 18) wearing complete dentures (CD) or removable partial dentures (RPD) Interventions for cleaning dentures in adults (2009) · Cochrane | The effectiveness of ultrasonic or microwave devices as an intervention for routine use was not studied according to a randomised controlled trial design (Implications for research). | 0 studies | No studies |
Healing and union of fracture (versus mal-union and non-union) · 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 |
Viral isolates · Patients being treated for cancer (leukaemia) Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer (2009) · Cochrane | RR 1.87 [1.12, 3.14] | 1 study · 60 participants | Ungraded |
Complication at augmentation + donor site · Patients with vertically deficient posterior/anterior mandibular ridges needing implants · Up to 3 years post-loading Interventions for replacing missing teeth: horizontal and vertical bone augmentation techniques for dental… (2009) · Cochrane | OR 0.3 [0.04, 2.11] | 1 study · 21 participants | Ungraded |
Partial reduction · 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 extracted | 0 studies | No studies |
Recurrence · 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 extracted | 0 studies | No studies |
Improvement in pain (proportion of participants improved/healed) · Adults with temporomandibular joint disorders (internal derangement; anterior disc displacement with or without… · 1 year Arthrocentesis and lavage for treating temporomandibular joint disorders (2009) · Cochrane | RR 1.09 [0.87, 1.38] | 1 study · 62 participants | Ungraded |
PAL gain < 2 mm (dichotomous) · 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 | RR 0.53 [0.34, 0.82] | 6 studies | Ungraded |
Number of individuals with oral lesions (8 days after administration); time to healing of oral lesions · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) · 8 days after administration Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | RR 0.10 [0.02, 0.38] | 1 study · 72 participants | Ungraded |