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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.
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 |
|---|---|---|---|
ARP with xenograft (bone graft) vs Extraction alone Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 36 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | 1 trial (Cha 2019) reported delayed healing with partial exposure of the buccal plate at suture removal by 1 participant in the test group; another trial (Festa 2013) reported pain and swelling | 2 studies · 54 participants | Low |
ARP with xenograft (bone graft) vs Extraction alone Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 36 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | RR 1.0 [0.07, 14.9] | 2 studies · 70 participants | Very low |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -0.87 [-1.61, -0.13] | 1 study · 18 participants | Very low |
ARP with alloplast vs ARP with xenograft Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | RR 1.09 [0.65, 1.83] | 2 studies · 37 participants | Very low |
ARP with allograft vs ARP with xenograft Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast vs Extraction alone Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with allograft vs ARP with xenograft Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -0.4 [-1.13, 0.34] | 3 studies · 87 participants | Very low |
ARP with alloplast vs ARP with xenograft Changes in vertical height of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -0.6 [-1.27, 0.07] | 1 study · 25 participants | Very low |
ARP with alloplast vs Extraction alone Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with demineralised bone matrix, single particle size vs ARP with demineralised bone matrix, multiple particle size Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with demineralised bone matrix, single particle size vs ARP with demineralised bone matrix, multiple particle size Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast vs ARP with xenograft Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Fibrous adhesions at the cervical part of previously preserved sockets were observed in 2 participants (Brkovic 2012) | 1 study · 20 participants | Very low |
ARP with alloplast vs Extraction alone Changes in vertical height of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -3.73 [-4.05, -3.41] | 1 study · 15 participants | Very low |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Included study (Fernandes 2011) reported there were no adverse effects | 1 study · 18 participants | Very low |
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD 0.43 [0.18, 0.68] | 1 study · 20 participants | Very low |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast vs Extraction alone Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Included study (Madan 2014) reported there were no adverse effects | 1 study · 15 participants | Very low |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Changes in vertical height of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -0.3 [-1.06, 0.46] | 1 study · 18 participants | Very low |
ARP with xenograft (bone graft) vs Extraction alone Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 36 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | RR 0.68 [0.29, 1.62] | 4 studies · 154 participants | Very low |
ARP with allograft vs ARP with xenograft Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | RR 6.36 [0.35, 115.73] | 1 study · 40 participants | Very low |
ARP with alloplast vs ARP with xenograft Complications (e.g. discomfort, pain and swelling) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | 1 trial (Patel 2013) reported pain, swelling, membrane exposure and partial loss of grafting material, while the other trial (Gholami 2012) reported that the procedure was uneventful | 2 studies · 37 participants | Low |
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with alloplast vs ARP with xenograft Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD -0.31 [-0.66, 0.04] | 2 studies · 37 participants | Very low |
ARP with demineralised bone matrix, single particle size vs ARP with demineralised bone matrix, multiple particle size Changes in bucco-lingual/palatal width of alveolar ridge (mm) · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | MD 0.1 [-0.97, 1.17] | 1 study · 30 participants | Very low |
ARP with alloplast vs ARP with xenograft Implant failure rate · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 to 8 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Not estimable; 1 trial (Patel 2013) reported that none of the implants failed after 12 months of loading | 1 study · 25 participants | Very low |
ARP with allograft vs ARP with xenograft Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with demineralised bone matrix, single particle size vs ARP with demineralised bone matrix, multiple particle size Need for additional augmentation prior to implant placement · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
ARP with allograft plus synthetic cell-binding peptide P-15 vs ARP with allograft without P-15 Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 6 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
Tooth- and tissue-supported removable partial denture: dual-impression technique with a different material vs An alternative dual-impression technique with a different material Outcome NR · 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 | We did not find any trials for this comparison. | 0 studies | No studies |
Alginate (two stage-two step final/wash impression) vs Silicone elastomer (two stage-two step) Number of border adjustments and sore spots after insertion of denture · Completely edentulous people Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Not measured | 0 studies | 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, left abutment Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 1.10 [0.46, 2.64] | 1 study | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step zinc-oxide eugenol (ZoE) traditional method Participant-reported quality of the denture (general satisfaction) · Completely edentulous people · 6 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | RR 3.15 [0.14, 72.88] | 1 study · 39 participants | Very low |
Ball (stud) attachment system vs Bar attachment system Re-treatment: replacement of attachment system (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 1.18 [0.38, 3.71] | 2 studies · 130 participants | Very low |
Ball (stud) attachment system vs Magnetic attachment system Cost of prosthodontic maintenance (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 | MD -247.37 [-346.32, -148.42] | 1 study · 69 participants | Very low |
Single-stage alginate impression (simplified method) vs Two stage-two step zinc-oxide eugenol (ZoE) traditional method Number of border adjustments and sore spots after insertion of denture · Completely edentulous people Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Not measured | 0 studies | No studies |
Ball (stud) attachment system vs Magnetic attachment system Prosthodontic success (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 0.84 [0.64, 1.10] | 1 study · 69 participants | Very low |
Ball (stud) attachment system vs Telescopic attachment system Prosthodontic success (specific 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 | no estimate extracted | NR | No studies |
Single-stage alginate impression (simplified method) vs Two stage-two step elastomer (silicone, polysulfide, or polyether) conventional method Operator-assessed quality of the denture · Completely edentulous people · 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 at six-month follow-up in operator-assessed quality of the dentures (Kawai 2005). | 1 study | Ungraded |
Altered-cast impression technique (ACIP), polyether vs One-piece cast technique (OPC), polyether Denture base adaptation (buccal shelf and ridge crest) · 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 | MD -0.11 [-0.18, -0.04] | 1 study | Ungraded |
Wax (fluid wax), two stage-two step selective pressure final impression vs Polysulfide rubber (elastomer) Participant-reported oral health-related quality of life (OHIP-EDENT) · Completely edentulous people Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Not measured | 0 studies | No studies |
Wax (fluid wax), two stage-two step selective pressure final impression vs Polysulfide rubber (elastomer) Participant-reported quality of the denture · Completely edentulous people Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Not measured | 0 studies | No studies |
Ball (stud) attachment system vs Bar attachment system Re-treatment: repair of attachment system (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 3.11 [1.68, 5.75] | 2 studies · 130 participants | Very low |
Ball (stud) attachment system vs Bar attachment system Prosthodontic success (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 | Considerable heterogeneity (I2 = 97%). Pooling of data was not done. See comment / See comment | 2 studies · 130 participants | Very low |
Selective pressure final-impression technique (two stage-two step, silicone elastomer) vs Traditional technique (redistributing pressure) and control technique (relatively mucostatic standard procedure) Participant preference for dentures · Completely edentulous people · 4 to 5 weeks Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | 33 participants chose dentures made using the selective pressure technique, 19 chose the traditionally-made denture and 14 chose the control denture. There was no clear preference between the traditional and control… | 1 study · 69 participants | 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-reported oral health-related quality of life (OHIP-EDENT) · Completely edentulous people · 3 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | OHIP-EDENT median scores: BPS 34.5; CCD 35.8. 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 Number of border adjustments and sore spots after insertion of denture · Completely edentulous people · 3 months Final‐impression techniques and materials for making complete and removable partial dentures (2018) · Cochrane | Median number of denture adjustments: BPS 3.5; CCD 4.5. BPS required fewer adjustments | 1 study · 10 participants | Very low |
Ball (stud) attachment system vs Bar 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 | Walton 2002 reported costs but the data could not be used due to failure to report means and standard deviations and only providing the median of the costs. | 1 study | Ungraded |