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 |
|---|---|---|---|
Effervescent tablets vs No treatment 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 |
Prophylactic valaciclovir (lower dose) vs Prophylactic valaciclovir (higher dose) Adverse effects · 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 | One study reported adverse effects (Warkentin 2002). Twenty patients allocated to receive high dose valaciclovir reported adverse effects (42%); for the low dose group this number was 27 (52%). Adverse effects were… | 1 study · 100 participants | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers 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 |
Brushing vs Effervescent tablets Total anaerobes (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD 4.44 [3.36, 5.52] | 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 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 |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers Postoperative complications (infection) / adverse events · 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 0.12 [0.02, 0.85] | 3 studies | Ungraded |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both 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 |
Arthrocentesis and lavage vs Arthroscopy 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 distraction osteogenesis vs Autogenous onlay bone graft (mandibular ramus) 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 |
Primary surgical intervention (curettage, peripheral osteotomy, or resection) vs Primary non-surgical intervention (intralesional corticosteroids, subcutaneous calcitonin, interferon alpha, or imatinib) 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 |
Resin-modified glass ionomer (Vitremer) vs Amalgam Marginal integrity, wear, surface texture, staining and secondary caries (Ryge criteria) at 6-12 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6-12 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Marginal integrity, wear, surface texture, axial contour, staining and secondary caries (Ryge criteria) at 6 and 12 months: odds ratios not estimable - no events recorded, implying equal performance of the two materials. | 1 study · 60 participants | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) 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 |
Prophylactic aciclovir (oral or intravenous) vs Prophylactic valaciclovir (oral) Cost of oral care · 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 | Only one trial reported on the cost of prophylaxis for HSV (Liesveld 2002). The reported mean pharmacy costs for those randomised to receive aciclovir were $1080 compared to $320 for those initially randomised to… | 1 study · 30 participants | Ungraded |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both 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 |
Compomer (Dyract) vs Amalgam (Tytin) Marginal integrity (occlusal) failures 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 10.76 [0.55, 211.78] | 1 study · 48 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) 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 |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) Postoperative complications (infection) / adverse events · 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 | Complications and other adverse events: none occurred. | 1 study | Ungraded |
Vertical distraction osteogenesis vs Autogenous onlay bone graft (mandibular ramus) 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 |
Aciclovir (oral or intravenous) for treatment vs Placebo Adverse effects · 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 | Adverse effects were assessed in both studies. For intravenous aciclovir the most commonly reported adverse effect was a reaction at the injection site (8 (16%) aciclovir versus 3 (7%) placebo; all patients, n = 97);… | 2 studies | Ungraded |
Inlay autogenous bone graft (iliac crest) vs Inlay bone substitute (Bio-Oss block) 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 |
1-stage (non-submerged) implant placement vs 2-stage (submerged) implant placement 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 |
Effervescent tablets vs Association of brushing and effervescent tablets 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 |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers 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 |
Arthrocentesis and lavage vs Arthroscopy 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 |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) 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 -1.60 [-2.74, -0.46] | 1 study | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) 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 | Radiographic bone level: no trial evaluated this. | 0 studies | No studies |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers 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 GBR with autogenous bone (retromolar) vs Vertical GBR with bone substitute (Regenaform) 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 |
Aciclovir (oral or intravenous) for treatment vs Placebo Cost of oral care · 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 studies | No studies |
Dental fillings (restorations) vs No treatment 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 |
Autogenous bone block from the chin 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 |
Silicone surfactant cleanser vs Placebo / sham solution 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 |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) 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 |
Brushing vs Association of brushing and effervescent tablets Fusobacteria (colony forming units, log-transformed) · Maxillary complete denture (CD) wearers Interventions for cleaning dentures in adults (2009) · Cochrane | MD 2.86 [2.25, 3.47] | 1 study · 18 participants | Ungraded |
Buccal onlay iliac grafts fixed with titanium screws vs Buccal onlay iliac grafts fixed with resorbable screws (split-mouth) 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 |
Enamel matrix derivative (EMD; Emdogain) vs Various bone grafting (BG) procedures (animal-derived or synthetic bone / bioactive ceramic filler) 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 |
Bioresorbable plates or screws (or both) vs Titanium plates or screws (used as lag screws) or both 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 |
Prophylactic prostaglandin E (oral) vs Placebo 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 |
Enamel matrix derivative (EMD; Emdogain) vs Guided tissue regeneration (GTR) with barriers 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 differences (one trial). | 1 study | Ungraded |
Vertical distraction osteogenesis vs Vertical GBR with non-resorbable barriers + particulate autogenous bone 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 |
Primary surgical intervention (curettage, peripheral osteotomy, or resection) vs Primary non-surgical intervention (intralesional corticosteroids, subcutaneous calcitonin, interferon alpha, or imatinib) 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 |
Primary surgical intervention (curettage, peripheral osteotomy, or resection) vs Primary non-surgical intervention (intralesional corticosteroids, subcutaneous calcitonin, interferon alpha, or imatinib) 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 |
Arthrocentesis and lavage vs Arthroscopy 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 |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) Postoperative complications (infection) / adverse events · 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 particular adverse events or infection attributable to EMD in any trial; no differences in pain, edema, hematoma, wound dehiscence or root sensitivity (Tonetti 2002). | 9 studies | Ungraded |
Enamel matrix derivative (EMD; Emdogain) vs Placebo or control (same surgical or non-surgical intervention without EMD) 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 |
Resin-modified glass ionomer (Vitremer) vs Amalgam Replacement (failure) of Class II restoration at 12 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 12 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 0.64 [0.10, 4.15] | 1 study · 60 participants | Ungraded |
Brushing 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 5.64 [4.86, 6.42] | 1 study · 18 participants | Ungraded |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Gingival health 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 | OR 0.30 [0.01, 8.32] | 1 study · 22 participants | Ungraded |