Table 1.
Characteristics of included studies.
| No. | Study | Study design | Participants and setting | Interventions | Outcome | Follow-up Period |
|---|---|---|---|---|---|---|
| 1. | Artun et al. 1997 | Prospective study |
n = 49 University of Washington, USA |
(i) Thick plain wire; 0.032 inch; mandible: only canines; n = 11 (ii) Thick spiral wire; 0.032 inch; mandible: only canines; n = 13 (iii) Thin, flexible spiral wire; 0.0205 inch; mandible: all 6; n = 11 (iv) Removable retainers; n = 14 |
Retainer failure | 3 years |
| 2. | Bazargani 2012 | RCT |
n = 52 (26 M, 26 F) Mean age 18.3 ± 1.3 years Orebro County Council, Sweden. |
(i) Resin, optibond FL; n = 26 (ii) Non-resin tetric evoflow; n = 26 Mandibular canine to canine Wire: 0 0.0195 inch multi-stranded penta-one wire |
Failure rate, incidence of retainer loss or breakage failure rate | 2 years |
| 3. | Taner 2012 | RCT |
n = 66 (52 F, 14 M) Mean age: 15.96 ± 3.21 in the direct group 19.44 ± 6.79 in the indirect groups University of Hacettepe, Turkey |
(i) Eight-braided flattened stainless steel; 0.022 inch −0.016 inch; mandible: all 6; direct bonding; n = 32 (2) Eight-braided flattened stainless steel; 0.022 inch −0.016 inch; mandible: all 6; indirect bonding; n = 34 Composite: phase II (CC) |
Failures of retainers as a result of debonding, fracture, debonding and fracture, or retainer loss | 6 months |
| 4. | Bolla et al. 2012 | RCT |
n = 85 (29 male, 56 female) Mean age: male 23.7 years, female 21.9 years |
(i) Glass fibre reinforced; maxilla: all incisors (n = 14); mandible: all 6 (n = 34) (ii) Multi-stranded wire, 0.0175 inch; maxilla: all incisors (n = 18); mandible: all 6 (n = 32) Composite: ENA bond LC primer and flowable composite (LC) |
The total number of detachments or bond failure and breakages | 6 years |
| 5. | Lee 2009 | Prospective study |
n = 300 Mean age: 15.6 ± 2.7 years Private practice, Canada. |
(i) Multi-stranded stainless steel; 0.0175 inch; straight wire; maxilla and mandible: all incisors or all 6; n = 153 (ii) Black Australian stainless steel; 0.016 inch; V-loop design; maxilla and mandible: all incisors or all 6; n = 147 Composite: Transbond LR (LC) |
Wire fractures, detachment rate due to bond failure | 6 months |
| 6. | Forde et al. 2018 | RCT |
n = 60 (15 F and 15 M with median age 16 in BR) (12 M and 18 F with median age of 17 in VFR) St Luke’s Hospital, York Hospital, and Leeds Dental Institute; UK. |
(i) BR (0.195 in three-stranded twist flex SS wire); n = 30 (ii) VFR; n = 30 Composite: Trasbond XT |
Retainer survival | 1 year |
| 7. | Gunay 2018 | RCT |
n = 120 Mean age 15.7 years (17 M and 43 F) in extraction group Mean age of 16.2 years (20 M and 40 F) in non-extraction group Ondokuz Mayıs University, Turkey |
(i) Extraction and 0.0175 in 60 stranded SS (n = 60) (ii) Non-extraction and 0.0195 in dead soft coaxial wire (n = 60) Composite: Trasbond XT |
Failure rate | 1 year |
| 8. | Ardeshna 2011 | Prospective study |
n = 51 University of Connecticut, USA |
(i) Maxilla: fibre-reinforced thermoplastic—FRP formula A; 0.53 mm; n = 1 (ii) FRP formula A; 1.02 mm; n = 1 (iii) FRP formula B; 0.53 mm; n = 6 (iv) FRP formula B; 1.02 mm; n = 8 (v) Mandible: fibre-reinforced thermoplastic—FRP formula A; 0.53 mm; n = 15 (vi) FRP formula A; 1.02 mm; n = 6 (vii) FRP formula B; 0.53 mm; n = 10 (viii) FRP formula B; 1.02 mm; n = 29 |
Retainer failure | 24 months |
| 9. | Zachrisson 1977 | Prospective study |
n = 43 Age: 14–17 years University of Oslo, Norway |
(i) Heat-treated and polished blue Elgiloy; 0.036 inch or 0.032 inch; mandible: only canines; held with finger during placement; n = 22 (ii) Heat-treated and polished blue Elgiloy; 0.036 inch or 0.032 inch; mandible: only canines; ligated during placement; n = 21 Composite: Concise (CC) |
Retainer loosening | 12 months |
| 10. | Salehi et al. 2013 | RCT |
n = 142 (59 male, 83 female) Age: 14–28 years |
(i) Polyethylene woven ribbon; maxilla and mandible: all 6; n = 68 (ii) Flexible spiral wire; 0.0175 inch; maxilla and mandible: all 6; n = 74 Composite: Fluoro Bond (sealant) and Heliosit Orthodontic (LC) |
Bond failure | 18 months |
| 11. | Talic 2016 | Prospective study |
n = 100 (37 F and 13 M in first group; 30 F and 20 M in second group) Mean age 21.4 ± 5.3 years for first group Mean age 20.48 years for second group King Saud University, Kingdom of Saudi Arabia |
(i) Fixed canine to canine retainers with a light-cured nano-hybrid composite based on nano-optimized technology (Tetric-N-Flow, Ivoclar Vivadent, Schaan, Liechtenstein) (ii) Fixed canine-to-canine mandibular and maxillary lingual retainers that were bonded with a light-cured LV composite (Transbond Supreme LV, 3M Unitek, Monrovia, California, USA) |
Failure rate | 6 months |
| 12. | Tacken et al. 2010 | RCT |
n = 184 patients (90 M, 94 F; 169 analysed) Mean age: 14 years University of Brussels, Belgium |
(i) Glass fibre reinforced (GFR500) maxilla: lateral incisor to lateral incisor (n = 45); mandible: all 6 (n = 45) (ii) Glass fibre reinforced (GFR1000); maxilla: lateral incisor to lateral incisor (n = 48); mandible: all 6 (n = 48) (iii) Six-stranded coaxial wire, 0.0215 inch; maxilla: lateral incisor to lateral incisor (n = 91); mandible: all 6 (n = 91) Composite: Excite and Tetric Flow (LC) |
Bond failure Retainer failure |
24 months |
| 13. | Egli et al. 2017 | RCT |
n = 64 Mean age 19.8 years in direct, 17.2 in indirect 61% F and 39% F in direct group 50% M and 50% F in indirect University of Geneva, Switzerland. |
(i) Direct bonding; n = 30 (ii) Indirect bonding; n = 30 Composite: direct bonding—Trasbond LR (LC), Indirect—maximum cure A and B (CC) Wire: Multi-stranded SS wire 0.0215 inch Mandibular laterals to laterals or canine to canine |
Failure rate | 2 years |
| 14. | Bovali 2014 | RCT |
n = 60 patients Mean age: 19.8 years (direct bonding), 17.2 years (Indirect bonding) University of Geneva, Switzerland. |
(i) Multi-stranded steel wire 0.0215 inch; mandible: all 6; n = 29; direct bonding (ii) Multi-stranded steel wire 0.0215 inch; mandible: all 6; n = 31; indirect bonding Composite: direct bonding, Transbond LR (LC); indirect bonding, Maximum Cure A and B (CC) |
Retainer failure | 6 months |
| 15. | Tang et al. 2013 | RCT |
n = 45 22 retainers in 18 patients 31 retainers in 27 patients Karolinska Institute and Uppsala County Council, Sweden |
(i) Transbond LR composite paste with liquid resin; n = 20 (ii) Liquid resin excluded; n = 20 Wire: 0.0215-inch multi-stranded wire Maxilla: all incisors; mandible: all 6 |
Failure rate | 5 years |
| 16. | Pandis et al. 2013 | RCT |
n = 220 (Median age, 16 years; interquartile range, 2 years; range, 12–47 years) Private practice, Greece. |
(i) Tru-Chrome multi-stranded wire; 0.022 inch; mandible: all 6; n = 110; Reliance (CC) (ii) Tru-Chrome multi-stranded wire; 0.022 inch; mandible: all 6; n = 110; Flow Tain (LC) Composite: Reliance (CC) and Flow Tain (LC) |
Bond failure | 3.64 years |
| 17. | Rose et al. 2002 | RCT | 20 patients (8 F, 12 M) Mean age 22.4 years Freiburg University, Germany |
(i) Polyethylene woven ribbon; mandible: all 6; n = 10 (ii) Multi-stranded steel wire; 0.0175 inch; mandible: all 6; n = 10 Composite: Heliosit Orthodontic (LC) |
Resin fracture or Retainer loosening | 2years |
| 18. | Arash et al. 2020 | RCT |
n = 260 (44 M and 68 F) Age: 13–30 years (20 ± 4.35 years) Babol University of Medical Sciences, Islamic Republic of Iran |
(i) 0.0175” twist flex wire (ii) Single stranded ribbon titanium Composite:Transbond XT (Mandibular anterior teeth) |
Failure rate Detachments, time of debonding, side effects |
2 years |
| 19. | Kartal et al. 2020 | RCT |
n = 52 (13 F and 13 M in first group; 19 F and 27 M in second group) Mean age 15.65 ± 2.17 18.42 ± 5.17 Private Practice, Turkey |
(i) Memotain retainers (CAD-CAM technology) 0.014” (ii) 0.0215” five-stranded retainers Composite:Transbond XT |
Success rate | 6 months |
| 20. | Scribante 2011 | RCT |
n = 34 patients (9 male, 25 female) Mean age: 14.3 years University of Pavia, Italy |
(i) Multi-stranded Stainless steel; 0.0175 inch; mandible: all 6, n = 17 (ii) Polyethylene ribbon-reinforced resin composite; mandible: all 6; n = 15 Composite: Transbond XT (LC) |
Bond failure | 12 months |
| 21. | Kramer et al. 2020 | RCT |
n = 104 (52 F and 52 M) Mean age 17.1 years in VFR Mean age 17.1 year in BR Orthodontic Clinic in Gavle, Sweden. |
(i) Cuspid to cuspid retainer (ii) VFR Wire: 0.8 Hard Remanium wire Composite:Tetric Flw composite |
Failure rate | 18 months |
| 22. | Gokce 2019 | Prospective study |
n = 100(61 F and 39 M) Age: 16.5–18 years Başkent University, Turkey |
(i) 0.0215 “MSW direct technique 0.0125 MSW indirect (ii) 0.0175 “MSW direct 0.0175 “MSW indirect Removable essix Transbond XT primer, 3M Unitek |
Failure rate | 6 months |
| 23. | Pop et al. 2018 | Prospective study |
n = 53 Age: 11–53 years Private clinic, Romania |
(i) 0.0175 inch Round fixed retainers (ii) 0.010–0.022-inch Flat wire retainers |
Success rate | 6 months |
| 24. | Sobouti et al. 2016 | RCT |
n = 150 Mean age 18 ± 3.6 years 23 M and 24 F in FRC splint 17 M and 24 F in FSW 20 M and 25 F in TW Mazandaran University of Medical Sciences, Iran |
(i) 0.0175-inch FSW (ii) FRC splint (iii) Twisted 2—0.009-inch dead soft wire Composite: Two layers of light-curable primer (Ormco, Orange, CA, USA) |
Failure rate, detachment, breakage, or distortion | 2 years |
| 25. | Stormann 2002 | RCT |
n = 103 Age: 22.4 ± 9.7 years Age: 13–17 years Orthodontic practice, Germany |
(i) Coaxial stainless steel 0.0215 inch; mandible: all 6; n = 36 (ii) Coaxial stainless steel 0.0195 inch; mandible: all 6; n = 30 (iii) Prefabricated; mandible: only canines; n = 32 Composite: Heliosit Orthodontic (LC) or Concise (CC) |
Bond failure | 2 years |
| 26. | Sfondrini 2014 | RCT |
n = 87 (52 F and 35 M) Age: 24 years (14–62 years) University of Pavia, Italy |
(i) Glass fibre reinforced; mandible: all 6; n = 40 (ii) Multi-stranded wire; 0.0175 inch; mandible: all 6; n = 47 Composite: Transbond XT (LC) |
Detachments of retainers from the teeth | 12 months |
| 27. | Nagani et al. 2020 | RCT |
n = 56 Age 20.88 ± 3.45 FRC 22.15 ± 3.68 MSW 4 M and 22 F in FRC 4 M and 22 F in MSR Dow University of Health Sciences, Pakistan |
(i) Fiber reinforced retainers; n = 27 (ii) Multi-stranded retainers; n = 27 Composite: Flowable composite resin (3 M ESPE) |
Retainer failure | 12 months |
| 28. | Shim 2022 | RCT |
n = 81 9 M,7 F, age median 16.5 in CAD/CAM 4 M, 12 F, median age 15.8 in Lab 5 M, 9 F, age median 15.2 in traditional group Saint Louis University, Missouri |
(i) CAD/CAM; n = 16 (ii) Lab; n = 16 (iii) Traditional; n = 14 |
Stability, failure of retainer | 6 months |
| 29. | Wegrodzka et al. 2021 | RCT |
N = 133 patients Median age, 24.6 years; 25th percentile, 17.2 years; 75th percentile, 32.4 years; minimum, 15.1 years; maximum, 49.8 years Private practice, Poland |
0.0215-inch stainless-steel three-strand RT wire retainer (Ortho Organizers, Lindenberg, Germany) 0.0265-inch 3 0.0106-inch eight-strand Bond-a-Braid wire retainer (Reliance Orthodontic Products, Itasca, Ill) |
Retainer failure, periodontal index, bleeding on probing, plaque index, gingival index, and probing depth. | 2 years |
| 30. | Cornelis et al. 2022 | RCT |
N = 64 participants University of Geneva, Switzerland |
Indirect bonding 26 Direct bonding 26 0.0215-inch multi-stranded stainless steel wire Transbond LR Light Cure Adhesive (3M, Monrovia, California) composite. |
Survival rate, the inter-canine and inter-premolar distances, and the observation of unexpected posttreatment changes | 5 years |
| 31. | Gera et al. 2022 | RCT |
N = 181 patients 98 in Centre 1, 83 in Centre 2 Aarhus University, Denmark University of Oslo, Norway. |
CAD/CAM group (n = 90) Conventional group (n = 91) |
Stability, retainer failures and patient satisfaction. | 6 months |
| 32. | Jowett et al. 2022 | Multicentre RCT |
N = 68 patients Leeds Dental Institute, St Luke’s Hospital, and Beverley Orthodontic Centre; UK |
Upper and lower Memotain® bonded retainers (n = 34) Upper and lower Ortho-FlexTechTM bonded retainers (n = 34) Separate etch and bond along-side Transbond LR (3M Unitek, Monrovia, CA, USA) resin-based composite: |
Stability of the inter-canine width and alignment of the labial segments, failure rate, patient satisfaction, and cost-effectiveness. | 6 months |
| 33. | Danz et al. 2022 | Prospective cohort study |
N = 200 participants Median age 14.7 (Range 11.1–57.0) University of Bern, Switzerland. |
0215 inches MW with separate curing of resin and composite (n = 200) 016 inches 022 inches SS wire with simultaneous curing of resin and composite (SS1C) (n = 200) 016 022 inches SS wire with separate curing of resin and composite (SS2C) (n = 200) |
Retention success, emergency, detachment, and retainer failure. | 1 year |
| 34. | Cokakoglu et al. 2023 | RCT |
N = 100 patients 70 females and 30 males Pamukkale University, Turkey |
Group 1, direct bonding (DB) with two-step adhesive (n =25) Group 2, DB with one-step adhesive (n = 25) Group 3, indirect bonding (IDB) with two-step adhesive (n = 25) Group 4, IDB with one-step adhesive (n = 25) The fixed retainer, a 0.0215-inch, five-strand stainless steel wire (Pentaflex; GC Orthodontics America Inc, Alsip, Ill) Bonded with the direct or indirect method using either the primer integrated one-step (GC Ortho Connect Flow; GC Corp, Tokyo, Japan) or two-step (conventional) retainer adhesive (Transbond LR; 3M Unitek, Monrovia, California) |
Plaque index, gingival index, and calculus index, failure rate. | 12 months |