| Author, year |
Country |
Study design |
Number
of patients (n) |
With
drawals
-
dropouts |
Results |
Comments |
Intervention
Fixed retainer |
Control
Removable retainer |
|
| Edman Tynelius, [13] |
Sweden |
RCT |
n=75
Group 1: n=25
Group 2: n=25
Group 3: n=25 |
n=6 |
Failure
During 24-months:
Group 1
7/25 (28%)
In 3 patients one failure.
In 3 patients two failures.
In 1 patient four failures.
|
Lost appliance
During (24-months):
Group 1 and 2
5/50 (10%)
Group 3
0/25 (0%)
p<0.01 (group 1 vs. 3)
ns. (group 1 & 2 vs. 3)
|
Failure rate (retainer loosening)
Lost appliance
Group 1= upper removable retainer (vacuum formed) and lower fixed retainer.
Group 2= upper removable retainer (vacuum formed) and lower stripping.
Group 3= removable retainer upper and lower (positioner).
p-values calculated from study data (Fisher’s exact test). |
| Artun, [11] |
USA |
RCT |
n=49
Group 1 n=11
Group 2: n=13
Group 3: n=11
Group 4: n=14 |
? a |
All fixed 8/35 (22.9%)
Group 1: 1/11 (9.1%)
Group 2: 4/13 (30.8%)
Group 3: 3/11 (27.3%)
|
Group 4: 2/14 (14.3%)
ns. |
Failure rate
Group 1= Mandibular cuspid retainer .032 plain wire.
Group 2= Mandibular cuspid retainer .032 spiral wire.
Group 3= Mandibular 3-3 retainer .0205 flexible spiral wire.
Group 4= Removable lower retainer.
Cuspid retainer- bonded only to cuspids.
3-3 retainer- bonded to each tooth |
| Cerny, [12] |
UK |
CT |
n=61
Group 1: n=46
Group 2: n=43
|
? a |
Clinical examination
6/46 (13%) patients with:
3 bond failures,
5 broken wires
Anamnesis (recall)
PBR fracture rate:
3.15%/year.
Bond/wire fracture rate: 0.58%/year |
- |
Failure rate (loosening or broken retainer).
Group 1 = Permanent bonded retainer (PBR ) (upper or lower).
Group 2 = Removable retainer (RR). |
| Andrén, [18] |
Sweden |
Case-series |
n=103
|
n=11 |
Loosening
Maxilla:
25/67 (37%) retainers
Mandible:
18/52 (35%) retainers
Wire fracture
Maxilla: 11 occasions
Mandible: 1 occasion |
- |
Failure rate (loosening or wire fracture).
Bonded lingual retainers maxilla and/or mandible (during 5 years of observation) 16 both arches, 41 maxillary retainers, 36 mandibular retainers. |
| Dahl, [17] |
Sweden |
Case-series |
n=153
Group 1: n=81
Group 2: n=72 |
n=11
(Group 1) |
Loosening (n=retainers)
Group 1
Maxilla: 14/56 (25.0%)
Mandible: 3/29 (10.3%)
Group 2
Maxilla: 5/64 (7.8%)
Mandible: 1/17 (5.9%)
Wire fracture (n=retainers)
Group 1
Maxilla: 13/56 (23.2%)
Mandible: 3/29 (10.3%)
Group 2
Maxilla: 2/64 (3.1%)
Mandible: 0/17 (0.0%)
Opening of small spaces
Group 1 and 2:
In 7 patients with retainer loosening
In 4 patients with intact retainers |
- |
Failure rate (loosening or wire fracture).
Other side effects.
Group 1 = Lingual bonded retainers (.0195’’ or .0215’’ three-stranded spiral wire).
(45 maxillary retainers, 14 mandibular retainers, 15 both arches).
Group 2 = Lingual bonded retainers (.0215 five-stranded spiral wire).
(55 maxillary retainers, 8 mandibular retainers, 9 both arches).
Mean period between orthodontic treatment and examination was 4.57±2.2 years
Small spaces = 0.5-1mm openings between teeth within the retained segments |
| Renkema, [21] |
Netherlands |
Case-series |
n=221 |
n=0 |
At least one bonding failure 70/221 (31.7%)
Less failures in incisors
than canines
p˂0.001
Central vs. lateral incisors
ns. |
- |
Failure rate
Bonded lingual mandibular retainer (.0195’’ 3-strand, heat-treated twist wire).
Observation period 5 years |
| Störmann, [19] |
Germany |
Case-series |
n=103
Group 1: n=31
Group 2: n=38
Group 3: n=34 |
n=5 |
Failure (% retainers)
Group 1: 29%
Group 2: 53%
Group 3: 18%
Increased patient discomfort with cuspid retainer |
- |
Failure rate
Group 1 = Bonded retainer .0195’’.
Group 2 = Bonded retainer .0215’’.
Group 3 = Cuspid retainer.
Cuspid retainer= bonded only to cuspids. |
| Tacken, [20] |
Belgium |
Case-series |
n=275
Group 1: n=45
Group 2 n=48
Group 3 n=91
Group 4: n= 90 |
n=15 |
Success rate (n=retainers)
Group 1 and 2:
(92/186) 49%
Group 3
161/182 (88%)
p<0.001
Failure
Group 1 and 2:
Maxilla:
Broken retainer 37/48 (77%) of all failures
Mandible:
Loosening 34/46 (74%)
of all failures
Group 3
Maxilla:
Loosening 10/13 (77%)
of all failures.
Mandible:
Loosening 8/8 (100%)
of all failures. |
- |
Success rate
Failure (loosening or broken retainer)
Group 1 = Glass fiber reinforced bonded retainer 500 fibres.
Group 2 = Glass fiber reinforced bonded retainer 1000 fibers.
Group 3 = Multi-stranded bonded retainer.
Group 4 = No retainer no treatment.
|
