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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 |
|---|---|---|---|
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Number of intaglio adjustments · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture · 1 year Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 1.43 [0.61, 3.34] | 1 study · 72 participants | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step elastomer (silicone, polysulfide, or polyether) conventional method Participant-reported quality of the denture (general satisfaction, VAS) · Completely edentulous people · 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | MD 0 [-8.23, 8.23] | 1 study · 105 participants | Very low |
Ball (stud) attachment system vs Bar attachment system Patient satisfaction / quality of life (validated measure) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | Only Walton 2002 assessed patient satisfaction but reported narrative results and failed to provide any usable numbers. Quality of life as assessed by a validated measure was not recorded in any of the trials. | 1 study | Ungraded |
Ball (stud) attachment system vs Telescopic attachment system Cost (treatment time and/or material costs) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | no estimate extracted | NR | No studies |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Operator-assessed gingival health of abutment · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture · 1 year, right abutment Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 1.05 [0.56, 1.98] | 1 study | Very low |
Alginate (two stage-two step final/wash impression) vs Silicone elastomer (two stage-two step) Participant-reported quality of the denture (comfort, stability, chewing efficiency) · Completely edentulous people · 2 weeks Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | The study reported that there was no difference between groups for comfort, but that more participants reported better stability and chewing efficiency with silicone. Data were not amenable to analysis. | 1 study | Ungraded |
Ball (stud) attachment system vs Telescopic attachment system Prosthodontic maintenance: patrix replaced (short term) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Short term (1 to 3 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | RR 6.00 [0.86, 41.96] | 1 study · 22 participants | Very low |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Participant-reported oral health-related quality of life · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Not measured | 0 studies | No studies |
Single-stage alginate impression (simplified method) vs Two stage-two step zinc-oxide eugenol (ZoE) traditional method Participant-reported oral health-related quality of life (OHIP-EDENT) · Completely edentulous people · 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | MD 0.5 [-2.67, 3.67] | 1 study · 39 participants | Very low |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Abutment mobility · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture · 1 year, left abutment Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 1.16 [0.40, 3.37] | 1 study | Very low |
Ball (stud) attachment system vs Telescopic attachment system Prosthodontic maintenance: matrix activated (short term) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Short term (1 to 3 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | RR 11.00 [0.68, 177.72] | 1 study · 22 participants | Very low |
Alginate (two stage-two step final/wash impression) vs Silicone elastomer (two stage-two step) Participant-reported oral health-related quality of life (OHIP-EDENT; lower score = better) · Completely edentulous people · 2 weeks Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | MD 7.20 [2.71, 11.69] | 1 study · 144 participants | Low |
Tooth-supported removable partial denture: same impression material, different final-impression technique vs The same material with an alternative final-impression technique Outcome NR · Partially edentulous people requiring a removable partial denture Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | We did not find any trials for this comparison. | 0 studies | No studies |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Abutment mobility · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture · 1 year, right abutment Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 2.90 [0.87, 9.61] | 1 study | Very low |
Ball (stud) attachment system vs Bar attachment system Prosthodontic maintenance (general categorization) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Short term (1 to 3 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | Recorded by Kappel 2016 and Walton 2002; they did not provide usable data for inclusion in the review. | 2 studies | Ungraded |
Wax (fluid wax), two stage-two step selective pressure final impression vs Polysulfide rubber (elastomer) Number of border adjustments and sore spots after insertion of denture · Completely edentulous people · 1 year Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 0.81 [0.38, 1.70] | 1 study · 27 participants | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step elastomer (silicone, polysulfide, or polyether) conventional method Mandibular denture satisfaction · Completely edentulous people · 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | SMD 0.21 [-0.11, 0.52] | 2 studies · 155 participants | Very low |
Ball (stud) attachment system vs Telescopic attachment system Patient satisfaction / quality of life (validated measure) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | Cepa 2017 assessed patient satisfaction but did not use validated measures and we could not use the data. Quality of life as assessed by a validated measure was not recorded. | 1 study | Ungraded |
Tooth-supported removable partial denture: different impression material, same final-impression technique vs The same technique with an alternative final-impression material Outcome NR · Partially edentulous people requiring a removable partial denture Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | We did not find any trials for this comparison. | 0 studies | No studies |
Single-stage alginate impression (simplified method) vs Two stage-two step elastomer (silicone, polysulfide, or polyether) conventional method Maxillary denture satisfaction · Completely edentulous people · 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | SMD -0.02 [-0.34, 0.29] | 2 studies · 155 participants | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step elastomer (silicone, polysulfide, or polyether) conventional method Participant-reported oral health-related quality of life (OHIP-EDENT) · Completely edentulous people · 1 month Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | MD 0.05 [-2.37, 2.47] | 2 studies · 98 participants | Very low |
Ball (stud) attachment system vs Magnetic attachment system Patient satisfaction / quality of life (validated measure) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | Two trials (Cune 2010; Naert 1999) reported patient satisfaction. However, we could not use any data from these studies. Quality of life as assessed by a validated measure was not recorded in any of the trials. | 2 studies | Ungraded |
Ball (stud) attachment system vs Magnetic attachment system Prosthodontic maintenance (general categorization) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | Recorded by Cristache 2014, Cune 2010 and Naert 1999; they did not provide usable data for inclusion in the review. | 3 studies | Ungraded |
Any attachment system for maxillary implant overdentures vs A different attachment system for maxillary implant overdentures Outcome NR · Edentulous adults receiving maxillary implant overdentures Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | no estimate extracted | NR | No studies |
Ball (stud) attachment system vs Magnetic attachment system Re-treatment: repair of attachment system (medium term) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Medium term (3 to 5 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | RR 1.75 [0.65, 4.72] | 1 study · 69 participants | Very low |
Alginate (two stage-two step final/wash impression) vs Silicone elastomer (two stage-two step) Participant preference for dentures · Completely edentulous people · 2 weeks Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Silicone impressions 57.7% (41 participants), alginate impressions 23.9% (17 participants); both equally satisfactory for 7 (9.9%) and equally unsatisfactory for 6 (8.5%) (McNemar chi-square 12.02, 1 df, P = 0.0005). | 1 study · 71 participants | Ungraded |
Ball (stud) attachment system vs Telescopic attachment system Prosthodontic maintenance: reline of implant overdenture (short term) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Short term (1 to 3 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | RR 2.33 [0.81, 6.76] | 1 study · 22 participants | Very low |
Ball (stud) attachment system vs Telescopic attachment system Prosthodontic maintenance: matrix replaced (short term) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) · Short term (1 to 3 years) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | RR 1.75 [0.71, 4.31] | 1 study · 22 participants | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step zinc-oxide eugenol (ZoE) traditional method Operator-assessed quality of the denture (retention and stability) · Completely edentulous people · 3 to 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | There was insufficient evidence of a clear difference between groups for operator-assessed quality of the dentures for retention and stability of dentures (Regis 2013). | 1 study | Ungraded |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Participant-reported quality of the denture (general satisfaction) · Partially edentulous people requiring a tooth- and tissue-supported (distal-extension) removable partial denture · 1 year Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | The study reported that 50 of 57 participants were moderately to completely satisfied, with no significant difference between the groups. Data not reported separately for each group. | 1 study · 57 participants | Low |
Ball (stud) attachment system vs Magnetic attachment system Patient preference (cross-over trials) · Edentulous adults receiving mandibular implant overdentures (opposing conventional complete maxillary dentures) Interventions for replacing missing teeth: attachment systems for implant overdentures in edentulous jaws (2018) · Cochrane | no estimate extracted | NR | No studies |
Biofunctional Prosthetic System (BPS): closed-mouth two stage-two step final impression with addition silicone elastomer vs Conventional complete denture technique (CCD): open-mouth two stage-two step conventional technique using elastomer Participant-reported quality of the denture (denture satisfaction, VAS) · Completely edentulous people · 3 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | VAS median scores: BPS 86.5; CCD 88. No clear difference between groups | 1 study · 10 participants | Very low |
Biofunctional Prosthetic System (BPS): closed-mouth two stage-two step final impression with addition silicone elastomer vs Conventional complete denture technique (CCD): open-mouth two stage-two step conventional technique using elastomer Participant preference for dentures · Completely edentulous people · 3 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | When participants were asked which denture they would prefer to use long term, nine out of 10 opted for the one made with the BPS complete denture technique. | 1 study · 10 participants | Ungraded |
Metal-free implant-supported FDPs (zirconia-toughened alumina; In-Ceram Zirconia) vs Metal-free implant-supported FDPs (yttria-stabilized tetragonal zirconia; Denzir) Periodontal/peri-implant status (secondary outcomes) · 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 for any of the pre-specified secondary outcomes. Follow-up visits registered pocket depth, bleeding on probing and mobility but the data were not reported. | 0 studies | No studies |
Metal-free FDPs (lithium disilicate) vs Metal-ceramic FDPs Aesthetic evaluation · 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 with regard to aesthetics. | 0 studies | No studies |
Metal-free FDPs (zirconia ceramic) vs Metal-ceramic FDPs Bridge failure · Adults (18 years or older) needing a three-unit fixed dental prosthesis (FDP) · 12 and 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | At 12 months and at 36 months 34 participants were available for analysis. No FDP failure was reported in either treatment approach at either time. | 1 study · 34 participants | Very low |
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, Distal Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.05 [-0.15, 0.04] | 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 · 60 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.02 [0.00, 0.42] | 1 study · 18 participants | Very low |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Plaque index (PI) · 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 -0.10 [-1.04, 0.84] | 1 study · 19 participants | Ungraded |
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 · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.83 [0.05, 13.44] | 1 study · 194 participants | Very low |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Cantilevered bridge failure · Adults (18 years or older) needing replacement of one premolar or incisor with a cantilevered fixed dental prosthesis · 12, 24 and 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | At 12 months 19 participants were available; no failure and no complication were reported in either group. No failure was reported at 24 or 36 months. | 1 study · 19 participants | Very low |
Metal-free cantilevered FDPs (feldspathic-veneered zirconia) vs Metal-ceramic cantilevered FDPs Gingival index (GI) · 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 0.03 [-0.75, 0.81] | 1 study · 19 participants | Ungraded |
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, Mesial to crown Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -0.01 [-0.93, 0.91] | 1 study · 18 participants | Ungraded |
Metal-free tooth-supported FDPs (pressed veneering ceramic) vs Metal-free tooth-supported FDPs (layered veneering ceramic) Aesthetic evaluation · Adults (18 years or older) needing a three-unit tooth-supported fixed dental prosthesis Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No comparative data were presented with regard to aesthetics. Aesthetics evaluated by the patient was reported dichotomously (yes/no) in the trial but no between-group estimate was presented. | 1 study | Ungraded |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Gingival/mucosal recession (REC) · 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 0.00 [-0.22, 0.22] | 2 studies · 47 participants | Ungraded |
Metal-free tooth-supported FDPs (pressed veneering ceramic) vs Metal-free tooth-supported FDPs (layered veneering ceramic) Periodontal/peri-implant status (secondary outcomes) · Adults (18 years or older) needing a three-unit tooth-supported fixed dental prosthesis Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | No comparative data were presented for the pre-specified secondary outcomes. The trial analyzed and reported plaque index, bleeding on probing and pocket probing depth but no between-group estimate was presented in the… | 1 study | Ungraded |
Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium) Abutment failure · 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 | OR 7.63 [0.33, 177.14] | 2 studies · 47 participants | Very low |
Metal-free FDPs (zirconia ceramic) vs Metal-ceramic FDPs Periodontal/peri-implant status (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. The trial registered pocket depth, bleeding on probing and mobility at follow-up visits but did not report the data. | 0 studies | No studies |
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 · 24 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 5.59 [0.23, 133.61] | 1 study · 19 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 · 12 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | MD -4.65 [-18.75, 9.45] | 1 study · 18 participants | Very low |