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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 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 |
|---|---|---|---|
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 |
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 |
ART using composite resin vs Conventional treatment using composite resin Restoration failure (permanent dentition) · Children with dental caries in primary teeth (mean age 7 years) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | No studies reported on restoration failure in the permanent dentition for this comparison. | 0 studies | No studies |
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 |
Fluoride supplementation (tablets, drops, lozenges or chewing gum) vs Placebo or no treatment Fluorosis (mandibular teeth) at 5 years · Pregnant women (for preventing dental caries in the primary teeth of their children) · 5 years Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing… (2017) · Cochrane | RR 0.89 [0.35, 2.29] | 1 study · 798 participants | Very low |
ART using resin-modified glass ionomer cement (RM-GIC) vs Conventional treatment using RM-GIC Secondary caries · Older adults with root caries in permanent (mature) teeth (mean age 75 years) · 6 months Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | One study reported data on secondary caries for this comparison (Cruz 2016). The odds of secondary caries at six months were greater with ART than with conventional treatment. | 1 study | 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 · 36 months Metal‐free materials for fixed prosthodontic restorations (2017) · Cochrane | OR 0.02 [0.00, 0.30] | 1 study · 18 participants | Very low |
ART using composite resin vs Conventional treatment using composite resin Adverse events · Children with dental caries in primary teeth (mean age 7 years) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | Adverse events: Not measured. | 0 studies | No studies |
Glass ionomer-based sealant vs No sealant (control/no treatment) Dentine caries in permanent molars (24 months) · Children and adolescents (general population, aged under 20 years) · 24 months Pit and fissure sealants for preventing dental decay in permanent teeth (2017) · Cochrane | Inconclusive results: two studies slightly favoured glass ionomers (Liu 2014b OR 0.46 (0.23-0.91); Tagliaferro 2011) evaluating 426 children; one study (Songpaisan 1995) found no difference (MD DFS -0.18 (-0.39 to… | 3 studies · 830 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 |
Dementia (any type or severity) vs Older people without dementia Root caries (mean number) · Older people (aged 60 years or older) with dementia Oral health and orofacial pain in older people with dementia: a systematic review with focus on dental hard… (2017) | no estimate extracted | 5 studies | 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 |
ART using H-GIC vs Conventional treatment using RM-GIC (with local anaesthetic) Restoration failure (permanent, mature teeth) · Adults with root caries in permanent (mature) teeth · Coronal and root caries Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 1.46 [0.74, 2.88] | 2 studies · 210 participants | Ungraded |
ART using high-viscosity glass ionomer cement (H-GIC), hand instruments vs Conventional treatment using H-GIC (rotary instruments) Secondary caries · People with dental caries in primary teeth (mainly children) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | Two studies reported on secondary caries, but this outcome was not reported by trial arm (Yu 2004; Roeleveld 2006). | 2 studies | Ungraded |
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 |
Fluoride supplementation (tablets, drops, lozenges or chewing gum) vs Placebo or no treatment Decayed primary surfaces at 3 years · Pregnant women (for preventing dental caries in the primary teeth of their children) · 3 years Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing… (2017) · Cochrane | MD 0.05 [-0.02, 0.12] | 1 study · 938 participants | Ungraded |
ART using glass ionomer cement (GIC) vs Conventional treatment using amalgam Restoration failure (permanent, immature teeth) · Children and adolescents with dental caries (primary teeth and permanent immature teeth) · Lesion type not reported Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 1.71 [1.32, 2.22] | 1 study · 1629 participants | Ungraded |
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 |
Resin-based fissure sealant (2nd/3rd/4th generation) vs No sealant (control/no treatment) Dentine caries in permanent molars (24 months) · Children and adolescents (general population, aged under 20 years) · 24 months Pit and fissure sealants for preventing dental decay in permanent teeth (2017) · Cochrane | OR 0.12 [0.08, 0.19] | 7 studies · 1322 participants | Moderate |
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 |
Dementia (any type or severity) vs Older people without dementia Edentulousness (prevalence) · Older people (aged 60 years or older) with dementia Oral health and orofacial pain in older people with dementia: a systematic review with focus on dental hard… (2017) | no estimate extracted | 11 studies | Ungraded |
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 |
ART using resin-modified glass ionomer cement (RM-GIC) vs Conventional treatment using RM-GIC Pain · Older adults with root caries in permanent (mature) teeth (mean age 75 years) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | Pain: Not measured. | 0 studies | No studies |
Glass ionomer-based sealant vs No sealant (control/no treatment) Adverse effects · Children and adolescents (general population, aged under 20 years) Pit and fissure sealants for preventing dental decay in permanent teeth (2017) · Cochrane | Adverse effects not measured. | NR | No studies |
Dementia (any type or severity) vs Older people without dementia Orofacial pain (prevalence) · Older people (aged 60 years or older) with dementia Oral health and orofacial pain in older people with dementia: a systematic review with focus on dental hard… (2017) | no estimate extracted | 7 studies | Ungraded |
Dementia (any type or severity) vs Older people without dementia Coronal caries (mean number) · Older people (aged 60 years or older) with dementia Oral health and orofacial pain in older people with dementia: a systematic review with focus on dental hard… (2017) | no estimate extracted | 5 studies | Ungraded |
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 |
ART using composite resin vs Conventional treatment using composite resin Restoration failure (primary dentition) · Children with dental caries in primary teeth (mean age 7 years) · 24 months, Multiple surface lesions Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 1.11 [0.54, 2.29] | 1 study · 57 participants | Very low |
ART using composite resin vs Conventional treatment using composite resin Secondary caries · Children with dental caries in primary teeth (mean age 7 years) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | No studies reported on secondary caries for this comparison. | 0 studies | No studies |
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 |
Fluoride supplementation (tablets, drops, lozenges or chewing gum) vs Placebo or no treatment Filled primary surfaces at 3 years · Pregnant women (for preventing dental caries in the primary teeth of their children) · 3 years Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing… (2017) · Cochrane | MD 0.07 [-0.07, 0.21] | 1 study · 938 participants | Ungraded |
ART using glass ionomer cement (GIC) vs Conventional treatment using amalgam Pain (permanent, immature teeth) · Children and adolescents with dental caries (primary teeth and permanent immature teeth) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | OR 0.41 [0.35, 0.47] | 1 study | Ungraded |
ART using resin-modified glass ionomer cement (RM-GIC) vs Conventional treatment using RM-GIC Restoration failure (primary dentition) · Older adults with root caries in permanent (mature) teeth (mean age 75 years) Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries (2017) · Cochrane | Restoration failure (primary dentition): 0 studies; No studies included. | 0 studies | No studies |
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 |
Glass ionomer-based sealant vs Resin-based sealant Adverse effects · Children and adolescents (general population, aged under 20 years) Pit and fissure sealants for preventing dental decay in permanent teeth (2017) · Cochrane | One trial measured adverse effects. None reported. | 1 study | 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 · 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 |