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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 |
|---|---|---|---|
Zirconia abutment vs Titanium abutment Abutment/crown fracture and marginal bone level (3 years) · Patients with single-tooth implant crowns; split-mouth, 3-year · 3 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | No fractures of any abutments or crowns; non-significant differences in mean marginal bone levels, which ranged from 1.6 to 2.1 mm (narrative) | 1 study · 22 participants | Ungraded |
Fixed dental prosthesis (cantilever FDP) vs Removable dental prosthesis (RDP) Patient satisfaction with prosthesis · Patients with a shortened dental arch (missing posterior teeth) Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | RR 1.22 [0.99, 1.51] | 1 study · 54 participants | Ungraded |
Er:YAG laser vs Air-abrasive device (Perio-Flow) Radiographic marginal bone level change · People with at least one dental implant affected by peri-implantitis · 6 months Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | After 6 months no statistically significant difference for peri-implant marginal bone levels. | 1 study · 42 participants | Ungraded |
Flapless implant placement vs Conventional flap elevation Implant failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 1.70 [0.32, 8.94] | 2 studies · 96 participants | Ungraded |
Zirconia framework FDP vs Metal framework FDP Survival / framework fracture (3 years) · Patients receiving FDPs; parallel group, 3-year · 3 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 100% survival and no framework fractures in either group after 3 years; no significant differences between groups with respect to porcelain fractures and mean survival time (narrative) | 1 study | Ungraded |
Crestal incision vs Vestibular incision Biological complications · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | Biological complications: Odds Ratio (M-H, Fixed, 95% CI), Subtotals only (no pooled estimate reported); 1 study (Heydenrijk 2000); 4 crestal vs 1 vestibular had hyperplastic tissue over the healing abutment | 1 study | Ungraded |
Technique to increase peri-implant keratinised/attached mucosa vs No increase of keratinised/attached mucosa Outcome NR · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | No trial: whether the peri-implant keratinised/attached mucosa has to be increased (objective 3a) - no trial identified | 0 studies | No studies |
Alternative alloy FDP (e.g., Ceramalloy II / base-metal / palladium-silver) vs High-gold content control alloy FDP (Olympia) Laboratory cost per unit · Patients receiving crowns and FDPs; split-mouth, 10-year · 10 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | Gold costs significantly higher: USD 89 per unit for gold compared to USD 53 for palladium-silver alloy and USD 37 for base-metal alloy | 1 study | Ungraded |
Tooth/implant FDP with rigid connectors vs Tooth/implant FDP with non-rigid connectors Non-scheduled maintenance visits · Patients with tooth/implant-supported FDPs; split-mouth · 5 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 70 non-scheduled maintenance visits to treat problems with rigid connectors compared to 110 visits for non-rigid connectors; unclear if this difference was considered significant | 1 study · 42 participants | Ungraded |
Flapless implant placement vs Conventional flap elevation Prosthetic failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 1.0 [0.14, 7.10] | 1 study | Ungraded |
One suturing technique/material vs A different suturing technique/material Outcome NR · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | No trial: which suturing techniques/materials are most effective (objective 4) - no trial identified | 0 studies | No studies |
Adjunctive local antibiotic (8.5% doxycycline hyclate, Atridox) added to manual debridement vs Manual debridement with chlorhexidine (no antibiotic) Change in probing pocket depth (PPD) · People with at least one dental implant affected by peri-implantitis · 4 months (18 weeks) Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | MD 0.59 [0.39, 0.79] | 1 study · 28 participants | Ungraded |
One soft tissue correction/augmentation technique vs A different soft tissue correction/augmentation technique Outcome NR · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | No trial: which soft tissue correction/augmentation technique is most effective (objective 2b) - no trial identified | 0 studies | No studies |
Crestal incision vs Vestibular incision Implant failure · Patients receiving dental implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | RR 3.0 [0.15, 59.89] | 1 study · 10 participants | Ungraded |
Nanocrystalline hydroxyapatite (Ostim) vs Bovine-derived xenograft (Bio-Oss) plus resorbable barrier Recurrence of peri-implantitis · People with at least one dental implant affected by peri-implantitis · 4 years Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | RR 2.0 [0.21, 18.98] | 1 study · 22 participants | Ungraded |
Implant surface smoothening added to systemic antibiotics + resective surgery + local antibiotics vs No implant surface smoothening (same surgical protocol) Complications and side effects · People with at least one dental implant affected by peri-implantitis · 2 years Interventions for replacing missing teeth: treatment of peri‐implantitis (2012) · Cochrane | No complications occurred in any of the groups. | 1 study · 17 participants | Ungraded |
Subepithelial connective tissue graft (palate) at implant placement vs No augmentation Aesthetics (pink aesthetic score, PES) evaluated by dentist · Partially edentulous patients receiving posterior mandibular implants Interventions for replacing missing teeth: management of soft tissues for dental implants (2012) · Cochrane | MD -2.87 [-3.67, -2.07] | 1 study · 20 participants | Ungraded |
Fixed partial denture supported by root-formed implants and remaining teeth (tooth/implant-supported) vs Fixed partial denture supported only by root-formed implants (implant-supported) Alveolar bone loss · Partially edentulous patients (mandible) receiving FDPs; split-mouth, 10-year · 10 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | No significant differences in alveolar bone loss: 0.6 to 0.7 mm for implant-supported versus 0.5 mm for tooth/implant FDPs (narrative) | 1 study · 23 participants | Ungraded |
Tilting-type RDP (minor connector design) vs Functional and sanitary RDP designs Patient satisfaction · Partially edentulous patients with a distal-extension RDP (minor connector); cross-over Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | The tilting-type RDP significantly outscored the functional and sanitary designs for patient satisfaction; within-patient SDs not given, data narrative only | 1 study · 25 participants | Ungraded |
RDP with lingual plate major connector vs RDP with sublingual bar major connector Abutment tooth mobility (Periotest) at 30 months · Partially edentulous patients treated with a mandibular RDP (major connector) · 30 months Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | MD -1.99 [-3.36, -0.62] | 1 study · 36 participants | Ungraded |
Altered-cast technique RDP vs One-piece cast RDP Patients with increased abutment tooth mobility · Partially edentulous patients treated with a distal-extension RDP Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | RR 1.81 [0.91, 3.58] | 1 study · 57 participants | Ungraded |
Titanium (Procera) abutment vs Gold-alloy (machined UCLA) abutment Success / prosthetic complications (4 years) · Patients with single-tooth implant crowns; split-mouth, 4-year · 4 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | 100% success, no prosthetic complications, and a similar loss of marginal bone (0.4 mm) in both groups (narrative) | 1 study · 20 participants | Ungraded |
RDP with I-bar clasps / mesial rests vs RDP with circumferential clasps / distal rests Treatment success (5-year) · Partially edentulous patients treated with a removable dental prosthesis (RDP) · 5 years Interventions for replacing missing teeth: partially absent dentition (2012) · Cochrane | HR 0.58 [0.25, 1.34] | 1 study · 134 participants | Ungraded |
Phosphoric etching (acid) gel vs Mechanical debridement and polishing Cleaning/treatment time · Adults with dental implants and healthy peri-implant soft tissues at baseline · 5 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | Both interventions took a similar time to administer (no statistically significant difference in cleaning time) | 1 study · 16 participants | Ungraded |
Immediate-delayed implants (placed within 8 weeks after tooth extraction) vs Delayed implants (placed at least 2 months after extraction) Major complications at the implant site · Patients with compromised teeth to be extracted who require single dental implants in fresh postextraction sockets · 5 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | RR 4.20 [1.01, 17.43] | 1 study · 46 participants | Ungraded |
Sonic toothbrushing vs Manual toothbrushing Patient satisfaction (liked toothbrush) · Adults with dental implants and peri-implant mucositis at baseline · 6 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | RR 1.48 [1.03, 2.13] | 1 study · 31 participants | Ungraded |
Bio-Oss (anorganic bovine bone) vs Bio-Oss + resorbable barrier Bone gain (horizontal - HDD) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 3 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | No statistically significant differences in bone gain between the two procedures for horizontal depth of the defect (HDD) (Chen 2007). | 1 study · 20 participants | Ungraded |
Mechanical debridement plus topical minocycline vs Mechanical debridement plus chlorhexidine gel Plaque · Adults with dental implants and peri-implant mucositis at baseline · 12 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD 6.00 [-9.07, 21.07] | 1 study · 32 participants | Ungraded |
Mechanical debridement with titanium curettes vs Mechanical debridement with ultrasonic device Plaque · Adults with dental implants and peri-implant mucositis at baseline · 6 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD 5.00 [-21.21, 31.21] | 1 study · 31 participants | Ungraded |
Listerine mouthwash vs Placebo mouthwash Plaque · Adults with dental implants and peri-implant mucositis at baseline · 3 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD -0.88 [-0.93, -0.83] | 1 study · 20 participants | Ungraded |
Non-resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Bone gain (vertical - VDH) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Vertical height of the defect (VDH). | 1 study · 25 participants | Ungraded |
Listerine mouthwash vs Placebo mouthwash Marginal bleeding · Adults with dental implants and peri-implant mucositis at baseline · 3 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD -0.20 [-0.25, -0.15] | 1 study · 20 participants | Ungraded |
Mechanical debridement with titanium curettes vs Mechanical debridement with ultrasonic device Change in probing pocket depth · Adults with dental implants and peri-implant mucositis at baseline · 6 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD -0.40 [-1.14, 0.34] | 1 study · 31 participants | Ungraded |
Non-resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Bone gain (horizontal - HDD) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Horizontal depth of the defect (HDD). | 1 study · 25 participants | Ungraded |
Immediate implants (placed in a fresh extraction socket just after tooth extraction) vs Delayed implants (placed at least 2 months after extraction, in healed bone) Perimplant marginal bone level changes · Patients with compromised teeth to be extracted who require single dental implants in fresh postextraction sockets · 1 year Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | No statistically significant differences for perimplant marginal bone level changes at 1 year (Lindeboom 2006). | 1 study · 50 participants | Ungraded |
Autogenous bone graft augmentation at the immediate implant site vs No augmentation Prosthesis failure · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | In total two implants were lost in the autogenous bone group, whereas no complications or failures occurred in the non-augmented control group; underpowered, no statistically significant difference (Chen 2005b). | 1 study · 26 participants | Ungraded |
Hyaluronic acid gel (brushing) vs Chlorhexidine gel (brushing) Marginal bleeding · Adults with dental implants and healthy peri-implant soft tissues at baseline · 6 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD 0.20 [-0.28, 0.68] | 1 study · 30 participants | Ungraded |
Amine fluoride/stannous fluoride (AmF/SnF2) mouthwash vs Chlorhexidine mouthwash Staining index · Adults with dental implants and healthy peri-implant soft tissues at baseline · 3 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD 0.06 [-0.10, 0.22] | 1 study · 33 participants | Ungraded |
Hyaluronic acid gel (brushing) vs Chlorhexidine gel (brushing) Plaque · Adults with dental implants and healthy peri-implant soft tissues at baseline · 6 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | MD -0.47 [-1.08, 0.14] | 1 study · 30 participants | Ungraded |
Phosphoric etching (acid) gel vs Mechanical debridement and polishing Side effects (pain) · Adults with dental implants and healthy peri-implant soft tissues at baseline · 5 months Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | Nine out of 16 patients reported slight (7) to moderate (2) pain at the etching gel side compared to none in the debridement group (P < 0.001) | 1 study · 16 participants | Ungraded |
Resorbable barrier (guided bone regeneration) vs Non-resorbable barrier (guided bone regeneration) Bone gain (horizontal - HDD) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Horizontal depth of the defect (HDD). | 1 study · 23 participants | Ungraded |
Powered toothbrushing vs Manual toothbrushing Change in probing pocket depth · Adults with dental implants and healthy peri-implant soft tissues at baseline · 6 weeks Interventions for replacing missing teeth: maintaining and recovering soft tissue health around dental… (2010) · Cochrane | At 6 weeks there was no significant difference in change of probing pocket depths | 1 study · 40 participants | Ungraded |
Bio-Oss (anorganic bovine bone) vs Bio-Oss + resorbable barrier Bone gain (vertical - VDH) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 3 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences in bone gain were found between the two procedures for vertical height of the defect (VDH) (Chen 2007). | 1 study · 20 participants | Ungraded |
Non-resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Major complications at the implant/donor site · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | Four complications occurred: two dehiscences in the resorbable group; one abscess and one dehiscence in the resorbable + autogenous bone group; none in the non-resorbable group. No statistically significant differences… | 1 study · 25 participants | Ungraded |
Immediate implants (placed in a fresh extraction socket just after tooth extraction) vs Delayed implants (placed at least 2 months after extraction, in healed bone) Prosthesis failure · Patients with compromised teeth to be extracted who require single dental implants in fresh postextraction sockets · 1 year Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | RR 4.33 [0.76, 24.56] | 2 studies · 110 participants | Ungraded |
Resorbable barrier (guided bone regeneration) vs Non-resorbable barrier (guided bone regeneration) Bone gain (vertical - VDH) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Vertical height of the defect (VDH). | 1 study · 23 participants | Ungraded |
Resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Bone gain (vertical - VDH) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Vertical height of the defect (VDH). | 1 study · 24 participants | Ungraded |
Resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Bone gain (horizontal - HDD) · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | All treatments resulted in statistically significant bone gain, however no statistically significant differences were found between the three procedures (Chen 2005a). Horizontal depth of the defect (HDD). | 1 study · 24 participants | Ungraded |
Resorbable barrier (guided bone regeneration) vs Resorbable barrier + autogenous bone Major complications at the implant/donor site · Patients receiving immediate single implants in fresh extraction sockets (maxillary anterior/premolar sites) · up to 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | Four complications occurred: two dehiscences in the resorbable group; one abscess and one dehiscence in the resorbable + autogenous bone group; none in the non-resorbable group. No statistically significant differences… | 1 study · 24 participants | Ungraded |
Immediate-delayed implants (placed within 8 weeks after tooth extraction) vs Delayed implants (placed at least 2 months after extraction) Aesthetics assessed by dentist: interproximal papilla dimension · Patients with compromised teeth to be extracted who require single dental implants in fresh postextraction sockets · 2 years Interventions for replacing missing teeth: dental implants in fresh extraction sockets (immediate,… (2010) · Cochrane | No statistically significant difference for the papilla height assessed by the dentist (Schropp 2003). | 1 study · 44 participants | Ungraded |