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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. Words match anywhere in the field.
581 questions in 23 reviews · Implants and prosthodontics
current versionsNo studies 87 · 15%Ungraded 388 · 66.8%Very low 88 · 15.1%Low 10 · 1.7%Moderate 8 · 1.4%High 0 · 0%
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 |
|---|---|---|---|
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Crown complications · Adults (18 years or older) needing a single crown in the molar or premolar region · 60 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 1.44 [0.59, 3.52] | 1 study · 158 participants | Very low |
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Crown complications · Adults (18 years or older) needing a single crown in the molar or premolar region · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 4.31 [0.49, 37.57] | 1 study · 194 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Aesthetic evaluation (patient satisfaction VAS) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.03 [-7.65, 7.59] | 1 study · 18 participants | Very low |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Bridge complications · Adults (18 years or older) needing an implant-supported fixed dental prosthesis in the posterior region · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.02 [0.00, 0.30] | 1 study · 18 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Marginal bone level (first bone to implant contact, FBIC) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 12 months, Mesial to crown Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.03 [-0.42, 0.36] | 1 study · 18 participants | Ungraded |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Implant probing pocket depth (PPD) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown on… · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.22 [-0.60, 0.16] | 2 studies · 47 participants | Ungraded |
Metal-free FDPs (lithium disilicate) vs Metal-ceramic FDPs Bridge complications · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 72 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.07 [0.01, 0.75] | 1 study · 22 participants | Very low |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Bridge failure · Adults (18 years or older) needing an implant-supported fixed dental prosthesis in the posterior region · 12, 36, 60 and 120 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No FDP failures were reported in either group at 12, 36, 60 or 120 months (18 participants; 17 at 120 months). | 1 study · 18 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Aesthetic evaluation (pink and white aesthetic score, PES and WES total) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.77 [-3.00, 1.46] | 1 study · 18 participants | Very low |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Aesthetic evaluation · Adults (18 years or older) needing an implant-supported fixed dental prosthesis in the posterior region Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No data were presented with regard to aesthetics. | 0 studies | No studies |
Metal-free tooth-supported FDPs (pressed veneering ceramic) vs Metal-free tooth-supported FDPs (layered veneering ceramic) Bridge failure · Adults (18 years or older) needing a three-unit tooth-supported fixed dental prosthesis · 12 and 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | At 12 months 40 participants were available and at 36 months 36 participants were available. No FDP failures were reported in either group at either time. | 1 study · 40 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Marginal bone level (first bone to implant contact, FBIC) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 24 months, Distal to crown Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.18 [-0.89, 0.53] | 1 study · 18 participants | Ungraded |
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Aesthetic evaluation · Adults (18 years or older) needing a single crown in the molar or premolar region Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No data were presented with regard to aesthetics. | 0 studies | No studies |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Marginal bone level change (MBLC) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown on… · 12 months, Mesial Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.39 [-0.43, -0.35] | 2 studies · 47 participants | Ungraded |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Bridge complications · Adults (18 years or older) needing an implant-supported fixed dental prosthesis in the posterior region · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.04 [0.00, 0.48] | 1 study · 18 participants | Very low |
Metal-free FDPs (lithium disilicate) vs Metal-ceramic FDPs Bridge failure · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 72 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 6.86 [0.66, 71.72] | 1 study · 22 participants | Very low |
Metal-free FDPs (lithium disilicate) vs Metal-ceramic FDPs Bridge failure · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 9.00 [0.96, 84.50] | 1 study · 37 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Implant crown failure · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 12 and 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | At 12 and 24 months 18 participants were available. No failure was reported for the test or control groups at either 12 or 24 months. | 1 study · 18 participants | Very low |
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Crown failure · Adults (18 years or older) needing a single crown in the molar or premolar region · 60 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 17.52 [5.07, 60.54] | 1 study · 158 participants | Very low |
Metal-free FDPs (zirconia ceramic) vs Metal-ceramic FDPs Bridge complications · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 1.94 [0.38, 9.88] | 1 study · 34 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Marginal bone level (first bone to implant contact, FBIC) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 12 months, Distal to crown Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD 0.09 [-0.28, 0.46] | 1 study · 18 participants | Ungraded |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Bridge complications · Adults (18 years or older) needing an implant-supported fixed dental prosthesis in the posterior region · 120 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.02 [0.00, 0.48] | 1 study · 17 participants | Very low |
Metal-free FDPs (lithium disilicate) vs Metal-ceramic FDPs Periodontal/peri-implant status and occlusal wear (secondary outcomes) · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No data were presented for any of the pre-specified secondary outcomes. | 0 studies | No studies |
Metal-free FDPs (zirconia ceramic) vs Metal-ceramic FDPs Aesthetic evaluation (patient aesthetic satisfaction changes) · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 15.40 [0.78, 304.61] | 1 study · 34 participants | Very low |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Cantilevered bridge complications · Adults (18 years or older) needing replacement of one premolar or incisor with a cantilevered fixed dental prosthesis · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 2.00 [0.15, 26.73] | 1 study · 19 participants | Very low |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Complications · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown on… · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | At 12 months no complications were reported in either group. | 2 studies · 47 participants | Very low |
Metal-free tooth-supported FDPs (pressed veneering ceramic) vs Metal-free tooth-supported FDPs (layered veneering ceramic) Bridge complications · Adults (18 years or older) needing a three-unit tooth-supported fixed dental prosthesis · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 2.80 [0.66, 11.92] | 1 study · 36 participants | Very low |
Metal-free implant-supported single crowns (zirconia veneered with feldspathic ceramic) vs Metal-ceramic implant-supported single crowns Implant crown complications · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 6.33 [0.26, 152.86] | 1 study · 18 participants | Very low |
Metal-free single crowns (full-contour zirconia) vs Cast gold (conventional metal) single crowns Periodontal/peri-implant status and occlusal wear (secondary outcomes) · Adults (18 years or older) needing a single crown in the molar or premolar region Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No data were presented for any of the pre-specified secondary outcomes. | 0 studies | No studies |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Aesthetic evaluation (Implant Crown Aesthetic Index, ICAI) · Adults (18 years or older) with one missing tooth in the aesthetic zone needing an implant-supported single crown on… · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | Primary outcome aesthetic evaluation data were reported as the frequency of distribution of the Implant Crown Aesthetic Index (ICAI); no comparative summary estimate was presented. | 2 studies · 47 participants | Very low |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Aesthetic evaluation (patient VAS) · Adults (18 years or older) needing replacement of one premolar or incisor with a cantilevered fixed dental prosthesis · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.34 [-0.85, 0.17] | 1 study · 19 participants | Very low |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Patient satisfaction · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… · 5 months after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Patient satisfaction was reported by one trial (Felice 2011); no usable pooled data. | 1 study | Ungraded |
Astra TiO2-blast titanium implants vs ITI SLA titanium implants Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 5 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | No failures; risk ratio not estimable (Akoglu 2011) | 1 study | Ungraded |
IMZ TPS titanium cylinders vs ITI TPS solid titanium screws Implant failure · 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 | RR 3.00 [0.13, 69.52] | 1 study · 40 participants | Ungraded |
Branemark Mark II turned titanium screws vs ITI TPS solid titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 3 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 0.05 [0.05, 5.20] | 1 study · 56 participants | Ungraded |
Bone substitute (anorganic bovine bone / Bio-Oss) vs A different bone substitute Implant failure · Patients undergoing two-stage maxillary sinus augmentation · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 1.00 [0.05, 18.30] | 1 study · 11 participants | Ungraded |
Maxillary sinus lift (augmentation) with long implants vs Short implants (5 to 8.5 mm) without sinus augmentation Treatment costs · Patients with missing teeth and an atrophic posterior maxilla, with residual bone height between 4 and 9 mm below the… Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Treatment costs: no trials reported this outcome (extrapolated by the review authors). Additional costs were associated with the long-implant + augmentation group (extra surgery, biomaterial, barrier, hospitalisation… | 0 studies | No studies |
Resorbable barrier (membrane) to seal the lateral window vs No membrane to seal the lateral window Implant 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 | OR 2.63 [0.75, 9.14] | 1 study · 104 participants | Ungraded |
ITI SLA titanium screws vs Southern blasted/etched titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 10 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | No failures at 10 years; risk ratio not estimable (Payne 2003, Table 4) | 1 study · 24 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Economic factors · 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 | Economic factors were not reported in any of the studies comparing two types of surgical anchorage | 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) Complications (sinus membrane perforation) · 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 0.82 [0.24, 2.84] | 1 study · 40 participants | Ungraded |
Early loading of mini-screw implant vs Delayed loading of 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 1.00 [0.83, 1.20] | 2 studies · 36 participants | Ungraded |
Bone substitute (anorganic bovine bone / Bio-Oss) vs A different bone substitute Augmentation procedure failure · Patients undergoing two-stage maxillary sinus augmentation · 1 year after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Augmentation procedure failure 0/11 versus 0/11; none. | 1 study · 11 participants | Ungraded |
NobelActive external connection implants vs NobelActive internal connection 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 0.30 [-0.17, 0.77] | 1 study · 97 participants | Ungraded |
IMZ TPS titanium cylinders vs ITI TPS hollow titanium screws Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 10 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 2.90 [0.12, 68.50] | 1 study · 59 participants | Ungraded |
Osteotomes with mallet (Summers' technique) vs Rotary instruments (Cosci technique) Implant failure · Patients undergoing crestal maxillary sinus lift · 3 years after loading Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | Checchi 2010 (N = 12): no implant failures in either group. | 1 study · 12 participants | Ungraded |
Branemark turned titanium screws vs IMZ TPS titanium cylinders Implant failure · Adults with missing teeth who received osseointegrated root-formed dental implants, functionally loaded and followed… · 1 to 10 years Interventions for replacing missing teeth: different types of dental implants (2014) · Cochrane | RR 1.00 [0.07, 15.26] | 1 study · 60 participants | Ungraded |
NobelReplace Select Tapered implants vs NobelReplace Groovy 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 3.00 [0.13, 70.92] | 1 study · 62 participants | Ungraded |
Autogenous bone graft (two-stage lateral sinus lift) vs Bone substitute (anorganic bovine bone / Bio-Oss) Complications · Patients with an atrophic posterior maxilla requiring maxillary sinus augmentation · up to 1 year Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus (2014) · Cochrane | OR 2.11 [0.18, 25.35] | 1 study · 40 participants | Ungraded |
Dual mini-screw implant vs Single mini-screw implant Number of visits · 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 | No studies reported on the number of visits for the comparison of two types of surgical anchorage | 0 studies | No studies |