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Do you do Damon®? What is the current evidence base underlying the philosophy of this appliance system?

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Self-ligating bracket systems are increasing in popularity amongst orthodontists. This reflects their high quality engineering, improved reliability and relative ease of use. However, it might also be related to claims of superior function made by the manufacturers of these appliances. In particular, the Damon(®) appliance system claims to offer significant advantages to both orthodontist and patient over conventional-ligation and other forms of self-ligated appliances. We have reviewed current literature relating to use of the Damon(®) appliance system. There is some evidence to suggest this appliance may lead to reductions in chairside time for the orthodontist, particularly those experienced with this system, in comparison to conventional-ligation. However, evidence that pain experience is reduced for the patient when using Damon(®) brackets is not conclusive. In the presence of identical archwire sequences, there is no evidence that Damon(®) brackets can align teeth faster or in a qualitatively differently manner, when compared with conventional-ligation. There is no high quality evidence that treatment with the Damon(®) appliance takes place more rapidly or leads to a superior occlusal or aesthetic result. Indeed, the best available evidence would suggest there is no difference in treatment outcome or time, at least in extraction cases. There is no evidence that treatment with the Damon(®) appliance is more stable. Claims relating to improved clinical performance of the Damon(®) appliance system are currently being made to orthodontists and patients that are not substantiated in the scientific literature.
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CUTTING
EDGE Do you do DamonH? What is the
current evidence base underlying the
philosophy of this appliance system?
Natasha Wright, Faranak Modarai, Andrew Thomas DiBiase and Martyn Cobourne
GKT Dental Institute, London, UK
Self-ligating bracket systems are increasing in popularity amongst orthodontists. This reflects their high quality engineering,
improved reliability and relative ease of use. However, it might also be related to claims of superior function made by the
manufacturers of these appliances. In particular, the DamonHappliance system claims to offer significant advantages to both
orthodontist and patient over conventional-ligation and other forms of self-ligated appliances.
We have reviewed current literature relating to use of the DamonHappliance system. There is some evidence to suggest this
appliance may lead to reductions in chairside time for the orthodontist, particularly those experienced with this system, in
comparison to conventional-ligation. However, evidence that pain experience is reduced for the patient when using DamonH
brackets is not conclusive. In the presence of identical archwire sequences, there is no evidence that DamonHbrackets can align
teeth faster or in a qualitatively differently manner, when compared with conventional-ligation. There is no high quality
evidence that treatment with the DamonHappliance takes place more rapidly or leads to a superior occlusal or aesthetic result.
Indeed, the best available evidence would suggest there is no difference in treatment outcome or time, at least in extraction
cases.
There is no evidence that treatment with the DamonHappliance is more stable. Claims relating to improved clinical
performance of the DamonHappliance system are currently being made to orthodontists and patients that are not
substantiated in the scientific literature.
Key words: Damon system, self-ligation, evidence, treatment efficiency
Received 17th February 2011; accepted 14th June 2011
Introduction
;Incorporating a self-ligating mechanism into the design
of an orthodontic bracket is not a new concept, but it is
only relatively recently that the many technological
difficulties associated with efficient design and large-
scale manufacture of these brackets have been largely
overcome. This has meant that a number of more robust
and reliable self-ligating brackets are now available
to the orthodontist and amongst these, the DamonH
System is one of the most popular. There are a number
of probable reasons for this pre-eminence, but the
simplicity and high quality engineering of the core
bracket design, availability of four subtly different
bracket types and utilization of a passive self-ligating
slot in combination with high technology archwires,
collectively make this an attractive appliance to use.
However, the DamonHappliance is also accompa-
nied by a specific treatment philosophy, which makes
numerous claims of specific clinical advantages asso-
ciated with using this system.
1
Significantly, these
proposed advantages are heavily marketed, aimed at
both orthodontist and patient, and in many cases can be
quite emotive. It is likely that this marketing has
contributed to the pre-eminence of this system.
To date, two systematic reviews have analyzed the
efficiency and effectiveness of self-ligating bracket sys-
tems in general and compared them to appliances with
conventional-ligation.
2,3
Thesehavecometoslightly
different conclusions, suggesting either that shortened
chairside time and slightly less incisor proclination are the
only significant advantages of self-ligation
2
or that there
is currently no evidence to support the use of these
systems over those with conventional-ligation.
3
A
Cochrane intervention protocol on the use of self-ligating
brackets for straightening teeth has been registered but is
yet to report.
4
Here, we review current evidence relating
to the DamonHappliance system, but this is not a
Journal of Orthodontics jor38.3_ Cutting Edge 11-13.3d 8/7/11 20:12:54
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
Journal of Orthodontics, Vol. 38, 2011, 219–227
Address for correspondence: Martyn Cobourne, GKT Dental
Institute, London, UK.
Email: martyn.cobourne@kcl.ac.uk
#2011 British Orthodontic Society DOI 10.1179/14653121141479
systematic review. The primary reason for this is that
despite the presence of over 50 publications relating to
DamonHSystem brackets, only three randomized con-
trolled trials (RCTs) have been carried out to date.
However, given the extent of the claims that accompany
this appliance we believe an appraisal of the current
literature is timely.
The DamonHlight force philosophy
The DamonHtreatment philosophy is based upon the
concept of providing only the minimum or threshold
force required to initiate tooth movement.
1
This is
achieved by the DamonHSystem, a combination of
passive self-ligation and superelastic nickel titanium
archwires (Figure 1). Together, this system is supposed
to produce a low force–low friction environment, which
facilitates more efficient tooth movement by ensuring
that the teeth remain within an optimal force zone
throughout treatment.
5
This theory is based upon the premise that low
orthodontic forces help maintain the patency of period-
ontal ligament blood vessels and facilitate maximal
cellular remodelling during tooth movement. This is
broadly consistent with conventional thinking, light
orthodontic forces are thought to be preferable because
of their ability to induce frontal resorption rather than
hyalinization and undermining resorption.
6
However,
the precise relationship between force magnitude and
orthodontic tooth movement is not fully understood
and has been the subject of several hypotheses.
7
Whether a truly optimal orthodontic force exists,
whereby a certain magnitude and temporal profile can
produce maximal tooth movement throughout the
dentition and without tissue damage or discomfort, is
debatable.
8
Indeed, mathematical modelling has identi-
fied a wide-range of forces that can all lead to a
maximum rate of tooth movement.
9
This is perhaps not
surprising, given that orthodontic forces are not
distributed evenly throughout the periodontal ligament
and that basic anatomical differences within the denti-
tion mean that different teeth will respond differently to
external force application. Therefore, the concept of one
appliance being able to produce a single, universal and
optimal orthodontic force throughout the dentition, is
probably over simplistic.
Physiologically adaptive mechanics
The DamonHSystem philosophy also claims that
maintaining teeth within this ‘optimal force zone’
throughout treatment allows ‘physiological adaption’
to take place. In theory, this means that the period-
ontium and orofacial muscles are never overpowered by
the orthodontic force, which allows the alveolar bone
and associated connective tissues to move with the teeth.
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Figure 1 DamonHself-ligating brackets (A) DamonH3; (B) DamonHMX; (C) DamonHQ and (D) conventional ligation
COLOUR
FIGURE
220 Wright et al. Cutting Edge JO September 2011
This represents something of a shift from traditional
orthodontic thinking and is controversial.
10
Moreover,
proponents suggest that because the forces are so light
within this system, the lips are able to restrain lower
incisor position, leading to alignment without labial
movement. In contrast, considerable expansion can be
achieved in the buccal segments, producing a broader
archform more in balance with the tongue and cheeks.
1
Given that it is practically easier to align teeth with the
secure robust ligation and superelastic wires used within
this system, it is further claimed that these combined
factors mean there is less need for tooth extraction when
using the DamonHSystem. This is accompanied by
faster tooth movement, extended intervals between
appointments, less overall visits to the orthodontist
and reductions in total treatment time. Finally, the
application of forces more in tune with periodontal
physiology means that there is also less overall pain and
discomfort for the patient.
Does the DamonHappliance apply less
force to the dentition?
The relative arguments regarding optimal orthodontic
force not withstanding, it would seem reasonable to
suggest that the use of minimal forces are beneficial for
tooth movement. Moreover, many laboratory studies
have demonstrated significant reductions in static fric-
tion associated with self-ligation.
11–14
Therefore, a key
question is whether the DamonHSystem does apply
quantitatively different forces to the teeth in comparison
to conventional-ligated appliances? In addition, are the
effects of these forces qualitatively different? Are the
tissue responses and types of tooth movement that can
be achieved fundamentally different from those with
conventional appliances?
It is not currently possible to measure the forces
applied by a fixed orthodontic appliance to the dentition
directly in vivo.
6
However, two independent laboratory-
based models have recently been developed that utilize
miniaturized multi-axis mechanical transducers to mea-
sure three-dimensional forces and moments. These devi-
ces have been used to simulate single arch orthodontic
treatment and quantify the effects of extruding a
vertically positioned maxillary canine
15
or aligning a
crowded mandibular arch
16
using 0.018 or 0.014-inch
copper nickel titanium archwires, respectively.
In the first investigation, the effects upon the canine,
adjacent lateral incisor and first premolar tooth were
compared using DamonHSystem brackets, either ligated
passively or with the addition of elastomeric ties. The
passive set-up produced a lower extrusive force on the
canine at maximum displacement and a relatively flat
unloading curve. In contrast, the addition of elasto-
meric ties produced more linear load-deflection and a
higher force at maximal displacement. The mesio-distal
forces (or resistance to sliding) and labio-lingual forces
were also higher for all the teeth in the presence of
conventional-ligation during both loading and unload-
ing. Therefore, this pilot investigation would suggest
that DamonHSystem passive ligation can produce a
lower force on the dentition, which is qualitatively
different to that seen in the presence of elastomeric
ligation.
15
However, it should be mentioned that this
research was funded, at least in part, by the manufac-
turer of the DamonHSystem bracket, with the lead
author acting as a consultant to that company.
17
In the second study, forces were compared during the
alignment of a lingually inclined crowded mandibular
lateral incisor using DamonHSystem 2 passive or In-
OvationRHactive self-ligation and OrthosHconventional-
ligation. Force levels were also found to vary between
bracket types but there was considerable heterogeneity in
the values obtained. Perhaps somewhat surprisingly, the
DamonHSystem 2 bracket was associated with a consi-
derably higher bucco-lingual force on the lateral incisor in
comparison to a conventionally-ligated OrthosH2 bracket.
This may be due to the fact that during ligation with
elastomeric ties, the tie itself will displace as the wire
disengages from the bracket slot, absorbing some of the
stored energy in the archwire. With the DamonH
System, because the gate on the slot is rigid, this does
not happen and all the energy in the wire is applied to
the tooth.
16
Other laboratory studies have also demonstrated
conflicting results when comparing force levels between
DamonHSystem and conventional-ligated brackets dur-
ing alignment. One of these investigations used a five-
tooth model of an upper right buccal segment to simulate
apical and buccal displacement of the canine and measure
forces released during alignment.
18–20
In comparison
to other types of passive self-ligating brackets or con-
ventional brackets ligated with either low-friction or
standard elastomerics, DamonHSystem MX brackets did
not consistently perform in a quantitatively different
manner. Interestingly, this investigation also demon-
strated that the lower resistance to sliding associated with
these brackets means that for a given archwire and de-
gree of irregularity, the residual tooth-moving force is
often higher, particularly for displacements greater than
3 mm.
18–20
However, a recent laboratory comparison of
force levels between coated and non-coated superelastic
archwires using DamonHSystem 2 and OrthosHconven-
tional-ligated brackets has demonstrated lower force
values for the DamonHSystem 2 bracket in loading and
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unloading, particularly in combination with the aesthetic
wires.
21
Although all of these studies only represent laboratory
models of the human mouth, collectively they demon-
strate that the forces applied to teeth during early tooth
alignment and levelling are complex and almost cer-
tainly influenced by multiple factors, not just the mode
of ligation. The DamonHbracket has been associated
with lighter forces in some, but not all, of the parameters
tested.
15,16,18–21
Do teeth align faster with the DamonH
appliance?
Attempts have been made to prospectively compare
rates of tooth alignment between subjects allocated to
DamonHSystem or conventional-ligated brackets, either
randomly
22,23
or using an alternating split-mouth design,
24
whilst a further investigation has randomly allocated and
compared subjects treated with DamonHSystem or active
self-ligating brackets.
25
All of these investigations have
reported data following initial alignment.
The investigations comparing DamonHSystem and
conventional brackets have concentrated on the align-
ment of mandibular incisor crowding. In the first of
these, DamonHSystem 2 brackets were compared with
MicroarchH(Orthos) conventional brackets during the
alignment of mild crowding (mean irregularity index of
5 mm) treated on a non-extraction basis.
22
Although the
archwire sequences differed between experimental groups
there was good pre-treatment equivalence. Overall, there
was a lack of statistical significance in the difference
between mean times to completion of alignment,
although this was marginal. However, survival analysis
based upon initial crowding did demonstrate a higher
alignment rate for the DamonHSystem 2 bracket in those
cases with moderate crowding (irregularity index ,5
mm). For more severe crowding (.5 mm) there were no
differences between bracket types.
In the second study, alignment rates were compared in an
RCT comparing DamonHSystem 3 and SynthesisH
(Ormco) conventional-ligated brackets in cases with more
severe incisor crowding, treated with the loss of first
premolars and an identical sequence of DamonHSystem
prescription archwires.
23
In this study, there were no
significant differences in either the rate of initial alignment
or the time to achieve complete alignment. The only
significant influence on rate of tooth movement was the
amount of initial crowding – the more crowded the teeth
were, the faster they moved, appliance type was irrelevant.
23
Finally, the split-mouth study used DamonHSystem 2
brackets and compared them to VictoryHMBT brackets
in subjects with very mild crowding (mean irregularity
index of around 2 mm), finding a statistically significant
reduction of the irregularity index in the conventional-
ligated bracket group during the first two archwire
changes at 10 and 20 weeks.
24
A split-mouth design was
used in this investigation for two main reasons. Firstly, it
was argued that an individual’s teeth are likely to respond
differently to the same applied pressure from a fixed
appliance and this methodology therefore allowed a
direct comparison of this response for each bracket type
for each person. Secondly, this study was also concerned
with discomfort, and a split-mouth design allows each
patient to give a personal comparison between each
bracket type without requiring a visual analogue scale,
which eases data gathering in the primary care environ-
ment that this study was set in. However, as the authors
acknowledge, one potential criticism of a split-mouth
design is that the presence of conventional brackets with
elastomeric modules on one half of the dental arch will
potentially inhibit free sliding of the DamonHSystem 2
brackets on the other side, reducing their clinical effec-
tiveness during initial alignment.
24
The DamonHSystem MX bracket has also been
compared directly with In-OvationRHactive self-ligating
brackets in the resolution of maxillary anterior arch
crowding.
25
An identical DamonHSystem archwire
sequence was used for the two groups and the time taken
to align the maxillary incisor teeth (mean irregularity
index of 7.5 mm) was measured. Alignment was judged
to be complete with visual inspection of the anterior
proximal contacts. Similarly to studies involving the
mandibular incisors, no differences in crowding allevia-
tion were found between the two brackets.
25
More recently, a group of patients treated consecutively
with DamonHSystem MX or conventional brackets (3M
VictoryHor Ormco Mini-DiamondH) and premolar ex-
tractions have been compared. These cases had a pre-
treatment irregularity index of around 12 mm and both
maxillary and mandibular arches were analyzed. There
were no significant differences in rate of alignment be-
tween the appliances at two separate time-points mea-
sured over a 20 week period.
26
Is tooth alignment qualitatively
different with the DamonHappliance?
The RCTs that have investigated mandibular incisor
alignment using DamonHSystem or conventional brack-
ets have also measured arch changes that take place in
the dentition during this process. Therefore, data are
available from an extended sample of just over 50 patients
with mild crowding treated on a non-extraction basis
22,27
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222 Wright et al. Cutting Edge JO September 2011
and a slightly larger sample with more severe crowding
treated with the loss of first premolars.
23
These investiga-
tions have provided very little evidence that the mechan-
ism of tooth alignment is fundamentally any different
when using the DamonHSystem in comparison to
conventional-ligation. Both appliances align teeth in the
mandibular arch primarily by incisor proclination and
increase in the inter-canine width, with any differences
between them insignificant (Table 1). In non-extraction
arches the DamonHSystem appliance does produce an
increase in the inter-molar width greater than that achieved
with conventional-ligation and this is significant;
22,27
how-
ever,inextractiongroupsthisdoesnotoccur–forboth
appliances the changes in inter-molar width were negligible
and not significant (Table 2).
23
Arch dimension changes have also been measured in
the reported sample of consecutive cases.
26
There were
also no significant differences between groups; inter-
canine width increased and arch depth decreased in
both arches, whilst inter-molar width increased in the
maxilla and decreased in the mandible. Interestingly,
there were also no differences in passive extraction
space closure between groups.
26
A further prospective
cohort study has investigated arch changes in cases
treated consecutively on a non-extraction basis with
DamonHSystem MX or conventional brackets.
28
This
investigation included only 13 subjects in each group
with mean lower arch crowding of 3.5 mm. No
significant differences were found between groups in
terms of inter-canine and inter-premolar width in-
creases or lower incisor proclination. The DamonH
System group did experience a statistically significant
increase in inter-molar width and lower incisor pro-
clination in relation to the A-Po line. However, the
results of this investigation need to be interpreted with
caution because of the study design; allocation was
non-random, the number of subjects in each group was
small and the groups were treated with different
archwires.
28
A further study has recently evaluated
incisor position and transverse dimensional arch
changes retrospectively in a group of class I cases
treated on a non-extraction basis using DamonH
System MX or conventional brackets.
29
The methodol-
ogy associated with this investigation was also poor
and the results should be treated with caution; however,
there were no significant differences between the
appliances in how tooth alignment was achieved,
primarily through arch expansion and incisor proclina-
tion. There was no evidence of any lip bumper effect in
the mandibular arch.
29
Arecentsystematicreviewofself-ligationhas
suggested that less incisor proclination might be one
generic advantage associated with using these brackets
2
and this has been reiterated in a recent forum.
30
Interestingly, all three of the studies that this conclusion
was based upon had compared mandibular incisor
position in cases treated with DamonHSystem or
conventional brackets.
23,27,28
However, in two of these,
the differences were actually less than one degree
23,28
and collectively none of the differences were of statistical
significance in any of the investigations. It is therefore
misleading to suggest that the use of self-ligation means
less incisor proclination (Figure 2).
Less pain for the patient?
Another major claim made for the DamonHSystem is
that it is associated with significantly less pain and
discomfort for the patient. Pain experience during
orthodontic treatment is notoriously subjective and
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Table 1 Alignment rate of DamonHSystem and conventional
brackets.
Bracket Number
Mean
crowding
(mm)
Days to
alignment
Pandis
et al.
22
DamonH2 27 5.50 91.03
Conventional 27 5.37 114.51
Scott
et al.
23
DamonH3 32 11.23 253
Synthesis 28 12.44 243
It is interesting to note that in Pandis et al.
22
those cases with .5mmof
irregularity had the fastest alignment rate. However, overall this was not
significant, almost certainly because mean irregularity of the whole sample
was only 5.43 mm (thus, very few cases within the sample actually had
.5 mm of irregularity).
Table 2 Arch changes with DamonHSystem and conventional
brackets.
Pandis
et al.
22
Jiang
and Fu
28
Pandis
et al.
27
Scott
et al.
23
LI MP DamonH7.41 9.9 3.1 1.73
Conventional 6.28 9.2 5.6 2.34
3-3 width DamonH1.08 0.57 1.6 2.66
Conventional 1.58 1.08 1.8 2.55
6-6 width DamonH2.04 1.42 2.4 20.09
Conventional 0.43 0.65 1.0 0.63
In the extraction group of Scott et al.
23
the DamonHSystem appliance
contracted the inter-molar width very slightly, which was in contrast to the
conventional appliances that expanded the inter-molar distance (although
overall these changes were not significant).
JO September 2011 Cutting Edge Damon system–what is the current evidence? 223
dependent upon multiple factors such as age, gender,
individual pain threshold and emotional state.
31
Advo-
cates of the DamonHSystem appliance argue that the
low orthodontic forces generated through passive self-
ligation results in less periodontal ligament ischemia and
therefore minimal discomfort. A number of studies have
measured subjective pain experience in samples treated
with DamonHSystem or conventional brackets.
24,32–34
In the only split-mouth study, discomfort was subjec-
tively recalled by participants a few days after appliance
placement and at 10 weeks, during both removal of the
first archwire and its replacement. Participants with
conventional brackets reported more discomfort a few
days after initial placement; however, at the first
archwire change, substantially more discomfort was
reported by those patients with the DamonHSystem 2
bracket.
24
In contrast, two groups of mildly crowded
patients treated with either DamonHSystem 2 or
VictoryHbrackets experienced highest pain intensity
from the VictoryHbrackets on placement of the first
archwire but from the DamonHSystem appliance on the
day following first archwire placement. Overall, it was
suggested that subjects with conventional-ligation had
more constant pain than those with DamonHSystem
brackets in the 7–9 days following archwire insertion.
Although this study is of interest, the methodology was
not robust; the sample size was small, participants were
not randomly allocated and appliances were only placed
in the maxillary arch.
34
To date there have been two RCTs comparing pain
and discomfort associated with DamonHSystem and
conventional brackets.
32,33
Both of these studies fol-
lowed CONSORT guidelines and used a self-reported
visual analogue scale during the first week following
appliance placement to evaluate pain experience. In the
first study there was a generalized reduction in perceived
pain as the week progressed for both groups, but no
significant differences in subjective discomfort be-
tween bracket types.
33
In the second investigation
patients in the DamonHSystem group reported both a
lowermeanpainintensityandlowermeanmaximum
pain intensity in comparison to the conventional
group, with these findings being significant for mean
pain and close to significant for maximum pain.
32
After adjusting for irregularity index and analgesia
consumption, there was an 11.77 mm difference in the
mean maximum pain intensity between groups.
However, the clinically relevant difference that was
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Figure 2 Alignment of a severely crowded mandibular arch using DamonHSystem mechanics on a non-extraction basis. Impressive
alignment can be achieved, although not without lower incisor proclination in this case at least
COLOUR
FIGURE
224 Wright et al. Cutting Edge JO September 2011
usedinthesamplesizecalculation for this study was
20 mm on the visual analogue scale; therefore, it is
unlikely that the difference between the two groups
was clinically relevant.
32
More efficient treatment?
There have been several retrospective cohort studies
investigating differences in overall treatment efficiency
between cases treated with DamonHSystem SL or
conventional orthodontic brackets.
35–37
These have all
found reductions in treatment time and total number of
appointments required when using the DamonHSystem
SL bracket and have been widely quoted as proving the
overall efficacy of this appliance.
38
One of these studies
should be disregarded because of the significant bias
arising from poor methodology and reporting, clear lack
of peer review and significant bias associated with the
retrospective sample acquisition.
37
Amongst the remain-
ing two studies, only one was able to demonstrate good
equivalence between samples,
36
but both demonstrated
reductions in overall treatment time for the DamonH
System groups, ranging from 4.10 (Ref. 36) to 6.30
months,
35
whilst the number of treatment visits were
fewer by 3.8 (Ref. 36) to 6.93.
35
The quality of treatment outcome was also assessed
using established occlusal indices. Using the American
Board of Orthodontics grading system, patients over the
age of 21 treated with the DamonHSystem bracket had
significantly higher scores; however, the scores were
lower for those under the age of 21.
35
In terms of the
Peer Assessment Rating, the DamonHSystem sample
had both a higher mean start score and a lower mean
finish score, although these differences were not
statistically significant.
36
A further retrospective study
investigating arch changes between non-extraction cases
treated with DamonHSystem MX or conventional
brackets does report in the abstract that patients treated
with the DamonHSystem bracket completed treatment
two months faster on average. However, there is no
specific data regarding treatment time included in the
results themself.
29
To date, one of the RCTs investigating DamonH
System versus conventional brackets has now published
final outcome data.
39
In these first premolar extraction
cases, bracket type had no effect on overall treatment
duration, number of visits, or overall Peer Assessment
Rating score reduction. As might be expected, the time
spent in space closure had an effect on treatment
duration; however, perhaps somewhat surprisingly, the
use of low-friction DamonHSystem brackets was not
able to reduce this.
39
Faster for the orthodontist?
A further proposed benefit of the DamonHSystem is the
speed of ligation, which offers significant potential time
savings for the clinician. Two studies have investigated
chairside time required to remove and then re-ligate
archwires with DamonHSystem brackets, compared with
conventional edgewise twin brackets.
36,40
One repre-
sented a pilot study measuring the time for archwire
removal and replacement with DamonHSystem SL
brackets,
29
whilst the other was a more extensive inves-
tigation using DamonH2 System brackets.
32
Both bracket
types required use of specific pliers for opening and
closing.
These studies showed a significant reduction in time
with the use of DamonHSystem brackets, both for
complete archwire changes and for opening individual
brackets, compared with conventional elastomeric liga-
tion. The order of difference was 16 seconds less to open
the DamonHbrackets and 9 seconds less to close
brackets, compared to conventional ligatures for a
complete arch
36
or 1.9 seconds less per bracket to close
the slide or place a ligature and 1 second less to open a
slide or remove a ligature.
40
The authors in the latter
study surmised that this equated to a 10% time saving
for an average archwire adjustment, which cumulatively
could add up to between 45 to 60 minutes of clinical
time per day. No studies to date have looked at speed of
ligation using the newer DamonHSystems, but con-
sidering that the slides can now be closed using finger
pressure, the time savings may well be even greater.
Stability of treatment
There are currently no investigations that have demon-
strated more stable occlusions following orthodontic
treatment with the DamonHSystem appliance when
compared to conventional appliances, either in extrac-
tion or non-extraction cases. It is claimed that the
DamonHSystem can achieve significant expansion in the
upper arch, with bodily tooth movement and bone
remodelling, without the need for rapid maxillary
expansion; moreover, this treatment is stable in the long
term.
41
There is no evidence to support this.
Will the debate be resolved?
For many orthodontists there is a feeling of de´ja`vu
regarding the claims of superiority associated with the
DamonHSystem treatment philosophy.
10
For others, the
philosophy has been embraced and patients are being
offered this system on the basis that it will be quicker, less
painful and less likely to require extractions. For many
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others this bracket system is being used conventionally, as
a well-designed and functional fixed orthodontic bracket
that will straighten teeth much like any other pre-adjusted
edgewise bracket.
In order to resolve some of this polarity of opinion and
provide the best evidence base to inform our patients,
further independent clinical research into this bracket
system is clearly required and these investigations should
be in the form of RCTs. However, there are obstacles.
One of the main criticisms from DamonHSystem
proponents is that the RCTs carried out to-date have
not followed the philosophy correctly and have therefore
disadvantaged the system. Whilst this may be true up to a
point, for many orthodontists, unbiased randomization
of significant malocclusions to treatment following the
DamonHSystem philosophy might be difficult to achieve
from an ethical point-of-view, particularly for the sample
receiving conventional ligation.
In many respect,s this is the modern dilemma,
manufacturers can make bold claims relating to the
superiority of their product, to both clinician and public
alike, with little or no real evidence supporting them.
42
For the independent researcher to prove that this
product, already licensed for sale, can deliver on these
claims requires the organization of complex and time-
consuming clinical trials, for which there is little
available funding and many challenging ethical dimen-
sions, which require intensive peer review before any
research can take place.
Conclusions
NThere is currently some evidence to suggest that use of
the DamonHSystem appliance may lead to reduced
chairside time for the orthodontist.
NFor the patient, evidence that pain experience during
treatment is reduced when using DamonHSystem
brackets is not conclusive.
NIn the presence of identical archwire sequences there is
no evidence that DamonHSystem brackets can align
teeth faster or in a qualitatively differently manner
when compared with conventional-ligation.
NThere is no high quality evidence that treatment with
the DamonHSystem appliance takes place more
rapidly, or leads to a superior occlusal or aesthetic
result.
NThere is no evidence that orthodontic treatment with
the DamonHSystem appliance is more stable.
NIt is disingenuous to offer treatment with the DamonH
System appliance to any patients on the basis that it
will be less painful, faster, preclude the need for
extractions or give a better result.
Acknowledgements
We thank Nikolaos Pandis for stimulating discus-
sion on the subjects of self-ligation and clinical trial
organization.
References
1. Damon D. Damon System: The Workbook. 2004.
2. Chen SS, Greenlee GM, Kim J-E, Smith CL, Huang GJ.
Systematic review of self-ligating brackets. Am J Orthod
Dentofacial Orthop 2010; 137: 726e1–18.
3. Fleming PS, Johal A. Self-ligating brackets in orthodontics.
A systematic review. Angle Orthod 2010; 80: 575–84.
4. Smith J, Bearn DR, House K. Self-ligating orthodontic
braces for straightening teeth. Cochrane Database Syst Rev
2008;CD007159.
5. Damon DH. The Damon low-friction bracket: a biologi-
cally compatible straight-wire system. J Clin Orthod 1998;
32: 670–80.
6. Krishnan V, Davidovitch Z. Cellular: molecular, and tissue-
level reactions to orthodontic force. Am J Orthod
Dentofacial Orthop 2006; 129: 469e1–32.
7. Quinn RS, Yoshikawa DK. A reassessment of force
magnitude in orthodontics. Am J Orthod 1985; 88: 252–60.
8. Ren Y, Maltha JC, Van’t Hof MA, Kuijpers-Jagtman AM.
Age effect on orthodontic tooth movement in rats. J Dent
Res 2003; 82: 38–42.
9. Ren Y, Maltha JC, Van’t Hof MA, Kuijpers-Jagtman AM.
Optimum force magnitude for orthodontic tooth move-
ment: a mathematic model. Am J Orthod Dentofacial
Orthop 2004; 125: 71–77.
10. Peck S. So what’s new? Arch expansion, again. Angle
Orthod 2008; 78: 574–75.
11. Budd S, Daskalogiannakis J, Tompson BD. A study of the
frictional characteristics of four commercially available self-
ligating bracket systems. Eur J Orthod 2008; 30: 645–53.
12. Ehsani S, Mandich MA, El-Bialy TH, Flores-Mir C.
Frictional resistance in self-ligating orthodontic brackets
and conventionally ligated brackets. A systematic review.
Angle Orthod 2009; 79: 592–601.
13. Krishnan M, Kalathil S, Abraham KM. Comparative
evaluation of frictional forces in active and passive self-
ligating brackets with various archwire alloys. Am J Orthod
Dentofacial Orthop 2009; 136: 675–82.
14. Thomas S, Sherriff M, Birnie DA. Comparative in vitro
study of the frictional characteristics of two types of self-
ligating brackets and two types of pre-adjusted edgewise
brackets tied with elastomeric ligatures. Eur J Orthod 1998;
20: 589–96.
15. Badawi HM, Toogood RW, Carey JP, Heo G, Major PW.
Three-dimensional orthodontic force measurements. Am J
Orthod Dentofacial Orthop 2009; 136: 518–28.
16. Pandis N, Eliades T, Bourauel C. Comparative assess-
ment of forces generated during simulated alignment with
Journal of Orthodontics jor38.3_ Cutting Edge 11-13.3d 8/7/11 20:13:29
The Charlesworth Group, Wakefield +44(0)1924 369598 - Rev 7.51n/W (Jan 20 2003)
226 Wright et al. Cutting Edge JO September 2011
self-ligating and conventional brackets. Eur J Orthod 2009;
31: 590–95.
17. Katz MI. Appearances count when industry underwrites
research. Am J Orthod Dentofacial Orthop 2010; 137:3
4.
18. Baccetti T, Franchi L, Camporesi M, Defraia E.
Orthodontic forces released by low-friction versus conven-
tional systems during alignment of apically or buccally
malposed teeth. Eur J Orthod 2011; 33: 50–54.
19. Baccetti T, Franchi L, Camporesi M, Defraia E, Barbato E.
Forces produced by different nonconventional bracket or
ligature systems during alignment of apically displaced
teeth. Angle Orthod 2009; 79: 533–39.
20. Franchi L, Baccetti T, Camporesi M, Giuntini V. Forces
released by nonconventional bracket or ligature systems
during alignment of buccally displaced teeth. Am J Orthod
Dentofacial Orthop 2009; 136: 316e1–6.
21. Elayyan F, Silikas N, Bearn D. Mechanical properties of
coated superelastic archwires in conventional and self-
ligating orthodontic brackets. Am J Orthod Dentofacial
Orthop 2010; 137: 213–17.
22. Pandis N, Polychronopoulou A, Eliades T. Self-ligating vs
conventional brackets in the treatment of mandibular
crowding: a prospective clinical trial of treatment duration
and dental effects. Am J Orthod Dentofacial Orthop 2007;
132: 208–15.
23. Scott P, DiBiase AT, Sherriff M, Cobourne MT. Alignment
efficiency of Damon3 self-ligating and conventional ortho-
dontic bracket systems: a randomized clinical trial. Am J
Orthod Dentofacial Orthop 2008; 134: 470e471–78.
24. Miles PG, Weyant RJ, Rustveld L. A clinical trial of
Damon2 vs conventional twin brackets during initial
alignment. Angle Orthod 2006; 76: 480–85.
25. Pandis N, Polychronopoulou A, Eliades T. Active or
passive self-ligating brackets? A randomized controlled trial
of comparative efficiency in resolving maxillary anterior
crowding in adolescents. Am J Orthod Dentofacial Orthop
2010; 137: 12e1–16.
26. Ong E, McCallum H, Griffin MP, Ho C. Efficiency of self-
ligating vs conventionally ligated brackets during initial
alignment. Am J Orthod Dentofacial Orthop 2010; 138:
138e131–37.
27. Pandis N, Polychronopoulou A, Makou M, Eliades T.
Mandibular dental arch changes associated with treatment
of crowding using self-ligating and conventional brackets.
Eur J Orthod 2009; 32: 248–53.
28. Jiang RP, Fu MK. Non-extraction treatment with self-
ligating and conventional brackets. Zhonghua Kou Qiang Yi
Xue Za Zhi 2008; 43: 459–63.
29. Vajaria R, Begole E, Kusnoto B, Galang MT, Obrez A.
Evaluation of incisor position and dental transverse
dimensional changes using the DamonHsystem. Angle
Orthod 2011, Mar 28 [Epub ahead of print].
30. Marshall SD, Currier GF, Hatch NE, et al. Ask us. Self-
ligating bracket claims. Am J Orthod Dentofacial Orthop
2010; 138: 128–31.
31. Ngan P, Kess B, Wilson S. Perception of discomfort by
patients undergoing orthodontic treatment. Am J Orthod
Dentofacial Orthop 1989; 96: 47–53.
32. Pringle AM, Petrie A, Cunningham SJ, McKnight M.
Prospective randomized clinical trial to compare pain levels
associated with 2 orthodontic fixed bracket systems. Am J
Orthod Dentofacial Orthop 200; 136: 160–67.
33. Scott P, Sherriff M, Dibiase AT, Cobourne MT. Perception
of discomfort during initial orthodontic tooth alignment
using a self-ligating or conventional bracket system: a
randomized clinical trial. Eur J Orthod 2008; 30: 227–32.
34. Tecco S, D’Attilio M, Tete S, Festa F. Prevalence and type
of pain during conventional and self-ligating orthodontic
treatment. Eur J Orthod 2009; 31: 380–84.
35. Eberting JJ, Straja SR, Tuncay OC. Treatment time,
outcome, and patient satisfaction comparisons of Damon
and conventional brackets. Clin Orthod Res 2001; 4: 228–34.
36. Harradine NW. Self-ligating brackets and treatment effi-
ciency. Clin Orthod Res 2001; 4: 220–27.
37. Tagawa D. From good to great: The Damon system versus
conventional appliances: a comparative study. Clinical
Impressions 2006; 15: 4–9.
38. http://www.DamonHbraces.com (accessed June 2011). <
39. Dibiase AT, Nasr IH, Scott P, Cobourne MT. Duration of
treatment and occlusal outcome using Damon3 self-ligated
and conventional orthodontic bracket systems in extraction
patients: a prospective randomized clinical trial. Am J
Orthod Dentofacial Orthop 2011; 139: e111–16.
40. Turnbull NR, Birnie DJ. Treatment efficiency of conven-
tional vs self-ligating brackets: effects of archwire size and
material. Am J Orthod Dentofacial Orthop 2007; 131: 395–99.
41. Damon D. Stability of the Damon system. Clinical
Impressions 2006; 15: 16–17.
42. O’Brien K, Sandler J. In the land of no evidence, is the
salesman king? Am J Orthod Dentofacial Orthop 2010; 138:
247–49.
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Authors Queries
Journal: Journal of Orthodontics
Paper: 38311CuttingEdge11
Title: Do you do DamonH? What is the current evidence base underlying the philosophy of this appliance
system?
Dear Author
During the preparation of your manuscript for publication, the questions listed below have arisen. Please attend to
these matters and return this form with your proof. Many thanks for your assistance
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Reference
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Journal of Orthodontics jor38.3_ Cutting Edge 11-13.3d 8/7/11 20:13:30
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... The system claims to apply just enough force to generate an "optimal force zone" so that dental arch expansion can be achieved without the use of a mechanical expander [9]. The Damon philosophy argues that the light force produced by the system allows the connective tissue and alveolar bone to follow tooth movement that results in a more predictable expansion of the maxillary arch in non-extraction cases, through the concept of stimulating cellular activity without damaging the vascular net of the periodontium [10]. As a result, common side effects seen in the RME such as dental tipping, extrusion, and root resorption may be minimized with the Damon System [11]. ...
... As a result, common side effects seen in the RME such as dental tipping, extrusion, and root resorption may be minimized with the Damon System [11]. In addition to the benefits listed above, the company also advertises the "lip bumper" effect on the incisors (minimizing anterior tipping), faster treatment, greater comfort, and better facial esthetic results [9,10]. ...
... Despite numerous claims of clinical advantages made by the Damon bracket manufacturer, the evidence behind their philosophy is weak [10]. Few studies evaluated the intermolar and intercanine width changes using Damon device; however, only one [12] study evaluated the skeletal and dental changes between Damon and traditional RME treatment. ...
Article
Full-text available
The purpose of this study was to evaluate and compare dental and skeletal changes associated with the Damon and Rapid Maxillary Expander (RME) expansion using Cone-Beam Computed Tomography (CBCT). Eighty-two patients, from The University of Alberta Orthodontic Clinic, were randomly allocated to either Group A or B. Patients in Group A received orthodontic treatment using the Damon brackets. Patients in Group B received treatment using the Hyrax (a type of RME) appliance. CBCT images were taken two times (baseline and after expansion). The AVIZO software was used to locate 18 landmarks (dental and skeletal) on sagittal, axial, and coronal slices of CBCT images. Comparison between two groups showed that transverse movement of maxillary first molars and premolars was much greater in the Hyrax group. The lateral movements of posterior teeth were associated with buccal tipping of crowns. No clinically significant difference in the vertical or anteroposterior direction between the two groups was noted. Alveolar bone next to root apex of maxillary first premolar and molar teeth showed clinically significant lateral movement in the Hyrax group only. The comparison between two groups showed significantly greater transverse expansion of the first molar and first premolars with buccal tipping in the RME group.
... The system claims to apply just enough force to generate an "optimal force zone" so that dental arch expansion can be achieved without the use of a mechanical expander [9]. The Damon philosophy argues that the light force produced by the system allows the connective tissue and alveolar bone to follow tooth movement that results in a more predictable expansion of the maxillary arch in non-extraction cases, through the concept of stimulating cellular activity without damaging the vascular net of the periodontium [10]. As a result, common side effects seen in the RME such as dental tipping, extrusion, and root resorption may be minimized with the Damon System [11]. ...
... As a result, common side effects seen in the RME such as dental tipping, extrusion, and root resorption may be minimized with the Damon System [11]. In addition to the benefits listed above, the company also advertises the "lip bumper" effect on the incisors (minimizing anterior tipping), faster treatment, greater comfort, and better facial esthetic results [9,10]. ...
... Despite numerous claims of clinical advantages made by the Damon bracket manufacturer, the evidence behind their philosophy is weak [10]. Few studies evaluated the intermolar and intercanine width changes using Damon device; however, only one [12] study evaluated the skeletal and dental changes between Damon and traditional RME treatment. ...
... As well, there are a diversity of fixed appliances description since one did not refer the type of buccal fixed appliances [31], one used self-ligated fixed appliance [33], three used a twin-bracket fixed appliance [6], and one also had lingual brackets [32,34]. Though passive self-ligating systems result in minor periodontal ligament ischemia and therefore less discomfort [35], literature evidences that pain experience in the beginning of treatment is independent of bracket type [36][37][38]. The type and size of archwires were described in four studies [6], though they differed in type and size among them, which is also a limitation worth mentioning. ...
Article
Full-text available
Featured Application: Clear aligners are associated with significantly less pain than fixed appliances during the first seven days of orthodontic treatment. Abstract: We aimed to compare the pain discomfort levels between clear aligners and fixed appliances at multiple time points. Four electronic databases (Pubmed, Medline, CENTRAL and Scholar) were searched up to May 2020. There were no year or language restrictions. Randomized clinical trials and case-control studies comparing pain perception through pain visual analog scale (VAS) in patients treated with clear aligners and with fixed appliances were included. Risk of bias within and across studies was assessed using Cochrane tool and Newcastle-Ottawa Scale (NOS) approach. Random-effects meta-analysis were conducted. VAS score and analgesic consumption were collected. Random-effects meta-analyses were used to synthesize available data. Following the review protocol, five articles met the inclusion criteria and were included, with a total of 273 participants (177 females, 96 males). Overall, clear aligners were associated with significantly less pain than fixed appliances during the first seven days of orthodontic treatment. Patients treated with clear aligners experience less pain discomfort than those treated with fixed appliances and consume less analgesics, with SORT A recommendation.
... While we build our criterion for selecting the proper bracket to try, promises from different manufacturing companies arise on the benefits of selfligating brackets. 2 As any tendency in science, four stages are identified ( Figure 1): the discovery or innovation, evaluation, counter-tendency and finally, consolidation or abandonment of the theory, which Khun describes as the scientific revolution of the paradigm. 3 The discovery or innovation has more to do with one stage of marketing than with the innovation per se; since in reality the fundamentals that created the first self-ligating brackets are theoretical and this is reflected in an increase in opinion articles of experts and case series. ...
Article
Objective To determine the inclination angles of buccal, palatal cortical plates and assess its harmony with existing molar buccolingual inclination in adults with different vertical facial heights. The aim of this study was to identify the role of cortical plate inclination as a diagnostic tool for determining alveolar support in adults with transverse discrepancies. Materials and Methods 157 CBCTs (50-Hypodivergent, 51-Normodivergent, and 56-Hyperdivergent growth patterns) of untreated adults were utilized. Cross-sectional slices with respect to the maxillary first molar were taken as orientation landmarks in defined reference planes. Inclination angles for the first molar, buccal and palatal cortical plate were determined with respect to the palatal plane. ANOVA and Post-Hoc Tukey’s HSD test were carried out to determine significant differences between groups. Results Molar inclination was significantly greater in hyperdivergent groups compared to normodivergent and hypodivergent groups (p<0.05). Greater variation between molar inclination and cortical plate inclination (buccal and palatal) was seen in hyperdivergent groups (p<0.05). Hypodivergent and normodivergent groups showed almost similar molar and cortical plate inclinations, however there was a significant difference between the buccal and palatal cortical plates (p<0.05). Conclusions Cortical plate inclination is in agreement with molar inclination in hypo-and normo-divergent groups when compared to hyperdivergent groups. In adults with decreased/normal facial heights, greater balance and harmony is observed between the dental and alveolar substructures in the posterior region. In adults with increased facial heights, a greater amount of dentoalveolar compensation is seen with respect to the molar and its surrounding bone support.
Article
Objective: To compare the skeletal and dentoalveolar changes produced by the Damon system's treatment philosophy to traditional orthodontic treatment techniques. Materials and methods: An electronic search in four major databases was completed: Cochrane, PubMed, EMBASE, and Google Beta Scholar on October 5th, 2018. Randomized controlled trials, prospective and retrospective controlled clinical trials were included in this systematic review. The quality assessment of individual studies was done using two different tools: The Cochrane Risk of Bias Assessment Tool (RTCs) and The Methodological Index for Non-Randomized Studies (MINORS) (non-RCTs). Results: Seven studies were included for this qualitative analysis. Six studies compared the Damon system to various types of conventional (non self-ligating bracket) system as a comparison group. One study used a quad helix as a comparison for a few months before a full bonding appointment with conventional brackets. The majority of studies found an increase in maxillary inter-canine, inter-premolar, and intermolar distance after the treatment in both the Damon and comparison groups. Yet, all studies concluded that there is no significant difference in the final transverse dimension between the two groups. One study also found that the transverse expansion was achieved mainly by tipping movement of posterior dentition, and a decrease in the posterior buccal bone area was evident in both groups after treatment. Conclusion: There is not enough evidence to support the claim that the Damon system allows additional arch expansion with better tipping control than with traditional techniques.
Thesis
Bien que la première attache auto-ligaturante en orthodontie fût inventée en 1930, elles se sont popularisées seulement depuis les années 2000. Avec deux grandes familles d’attaches : les auto-ligaturantes passives et les auto-ligaturantes actives. L’objectif de ce travail est de réaliser une revue de littérature sur l’utilisation des attaches auto-ligaturantes en orthodontie, de définir les principes des attaches actives et passives et de comparer les forces de frottement, l’efficacité du traitement, le temps gagné au fauteuil et le confort d’utilisation entre les systèmes auto-ligaturants et les systèmes conventionnels.
Article
Background and objectives: From the beginnings of modern orthodontics, questions have been raised about the extraction of healthy permanent teeth in order to correct malocclusions. A hundred years ago, orthodontic tooth extraction was debated with almost religious intensity by experts on either side of the issue. Sheldon Friel and his mentor Edward H. Angle both had much to say about this controversy. Today, after significant progress in orthodontic practice, similar arguments are being voiced between nonextraction expansionists and those who see the need for tooth extractions in some orthodontic patients. Furthermore, varying concepts of mechanical retention of treatment results have evolved over the years which have been misinterpreted as enhancing natural orthodontic stability. Materials and methods: In this essay, representing the Ernest Sheldon Friel Memorial Lecture presented in 2016 at the 92nd Congress of the European Orthodontic Society, a full spectrum of evidence from biology, anthropology and history is critically discussed in the search for truth among highly contested orthodontic variables: extraction versus nonextraction, fixed retention versus limited retention, and rationalized stability versus biological homeostasis. Conclusions and implications: Conscientious clinicians should try to develop individualized treatment plans for their patients, and not be influenced by treatment 'philosophies' with untested claims in clinical orthodontics.
Article
The review examines some of the potential risks of orthodontic therapy along with their evidence base. The risks of orthodontic treatment include periodontal damage, pain, root resorption, tooth devitalisation, temporomandibular disorder, caries, speech problems and enamel damage. These risks can be understood to arise from a synergy between treatment and patient factors. In general terms, treatment factors that can influence risk include appliance type, force vectors and duration of treatment whilst relevant patient factors are both biological and behavioral. Hence the natural variation between orthodontic treatment plans and patients gives rise to variations in risk. A good understanding of these risks is required for clinicians to obtain informed consent before starting treatment as well as to reduce the potential for harm during treatment. After considering each of these risks, a conceptual framework is presented to help clinicians better understand how orthodontic risks arise and may therefore be mitigated. This article is protected by copyright. All rights reserved.
Article
Full-text available
Objective: To compare the amount of expressed frictional resistance between orthodontic self- ligating brackets and conventionally ligated brackets in vitro as reported in the literature. Methods: Several electronic databases (Medline, PubMed, Embase, Cochrane Library, and Web of Science) were searched without limits. In vitro studies that addressed friction of self-ligating brackets compared with conventionally ligated brackets were selected and reviewed. In addition, a search was performed by going through the reference lists of the selected articles to identify any paper that could have been missed by the electronic searches. Results: A total of 70 papers from the electronic database searches and 3 papers from the secondary search were initially obtained. After applying the selection criteria, only 19 papers were included in this review. A wide range of methods were applied. Conclusions: Compared with conventional brackets, self-ligating brackets produce lower friction when coupled with small round archwires in the absence of tipping and/or torque in an ideally aligned arch. Sufficient evidence was not found to claim that with large rectangular wires, in the presence of tipping and/or torque and in arches with considerable malocclusion, self-ligating brackets produce lower friction compared with conventional brackets. (Angle Orthod. 2009;79: 592-601.)
Article
The aim of the in vitro study was to investigate the frictional characteristics of two types of self-ligating brackets ('A' Company Damon SL and Adenta Time brackets) and two types of pre-adjusted edgewise brackets (TP Tip-Edge and 'A' Company Standard Twin brackets). The test brackets were glued to steel bars and aligned using a preformed jig. Five combinations of archwire size and material were used (0.014-inch nickel titanium, 0.0175-inch multistrand stainless steel, 0.016 x 0.022-inch nickel titanium, 0.016 x 0.022-inch stainless steel and 0.019 x 0.025-inch stainless steel wires). The wires were drawn through the brackets and the frictional resistance was measured using an Instron 1193 testing machine. The data were analysed using a one-way analysis of variance and Scheffe's multiple comparison of means test. The results revealed that the Damon brackets demonstrated the lowest friction for all dimensions of test wires followed by the Time bracket. The 'A' Company Standard Twin brackets produced the highest friction with all wire dimensions tested, followed by the Tip-Edge bracket. With all brackets the 0.016 x 0.022-inch nickel titanium wires produced a higher frictional resistance than the 0.016 x 0.022-inch stainless steel wires. The results indicate that these self-ligating brackets produce less frictional resistance than elastomerically-tied pre-adjusted edgewise brackets.
Article
A number of laboratory studies have shown very low levels of archwire friction for self-ligating brackets when compared to conventional ligation methods. However, justifiable reservations have been expressed as to the in vivo relevance of these findings. This study was designed to compare treatment efficiency with conventional fully programmed brackets and Damon SL self-ligating brackets. Thirty consecutively finished cases treated by the author with Damon SL brackets were compared with 30 matched cases treated by the author with conventional brackets. Parallel studies quantified the incidence of technical problems with Damon SL brackets and with conventional ligatures and also the chairside time required for ligation/slide closure and ligature removal/slide opening with these two bracket types. The Damon SL cases required an average of four fewer months and four fewer visits to be treated to an equivalent level of occlusal regularity as measured by the PAR scores.
Article
Efficiency of treatment mechanics has been a major focus throughout the history of orthodontics. Self-ligating brackets were developed on the premise that elimination of ligature ties creates a friction-free environment and allows for better sliding mechanics. It is expected that the self-ligating bracket will reduce the treatment time. This study was designed to compare the effectiveness and efficiency of Damon self-ligating (SL) brackets to those brackets ligated with either steel ligatures or elastomeric ‘O’ rings. Not only treatment time and the number of appointments needed were addressed, but the quality of the treatment outcome was also assessed. American Board of Orthodontics (ABO) grading criteria for models and panoramic radiographs were employed. Additionally, a nine-question survey was sent to the 215-patients in this study (108 Damon, 107 conventionally-ligated) to elicit their perceptions of how their orthodontic treatment progressed and finished. The results showed that patients treated with Damon SL brackets had significantly lower treatment times, required significantly fewer appointments, and had significantly higher ABO scores than those treated with conventionally-ligated edgewise brackets. There were no significant differences in Damon or non-Damon ABO scores with respect to gender. Damon patients over the age of 21 had significantly higher ABO scores. Conversely, the non-Damon patients under the age of 21 had significantly higher ABO scores. For pre-treatment Angle classification, no significant differences were noted. Patient responses showed that Damon patients perceived their treatment time as being shorter than expected. It appears that faster orthodontic treatment can be better as measured by the ABO criteria.
Article
To test the hypotheses that the Damon system will maintain intercanine, interpremolar, and intermolar widths. To test subsequent hypotheses that the Damon system will not produce a significant difference in maxillary and mandibular incisor position/angulation when compared with control groups treated with conventional fixed orthodontic appliances for similar malocclusion. Subjects treated with the Damon system (N  =  27) were compared with subjects treated with a conventionally ligated edgewise bracket system (N  =  16). Subjects' pretreatment and posttreatment lateral cephalometric radiographs and dental models were scanned, measured, and compared to see whether significant differences exist between time points and between the two groups. Results did not support the claimed lip bumper effect of the Damon system and showed similar patterns of crowding alleviation, including transverse expansion and incisor advancement, in both groups, regardless of the bracket system used. Maxillary and mandibular intercanine, interpremolar, and intermolar widths increased significantly after treatment with the Damon system. The mandibular incisors were significantly advanced and proclined after treatment with the Damon system, contradicting the lip bumper theory of Damon. Posttreatment incisor inclinations did not differ significantly between the Damon group and the control group. Patients treated with the Damon system completed treatment on average 2 months faster than patients treated with a conventionally ligated standard edgewise bracket system.
Article
This was a prospective randomized clinical trial comparing the effect of bracket type on the duration of orthodontic treatment and the occlusal outcome as measured by the peer assessment rating (PAR). A multi-center randomized clinical trial was carried out in 2 orthodontic clinics. Sixty-two subjects (32 male, 30 female; mean age, 16.27 years) with a mean pretreatment PAR score of 39.40, mandibular irregularity from 5 to 12 mm, and prescribed extractions including mandibular first premolars were randomly allocated to treatment with either the Damon3 self-ligated or the Synthesis conventional ligated preadjusted bracket systems (both, Ormco, Glendora, Calif). An identical archwire sequence was used in both groups excluding the finishing archwires: 0.014-in, 0.014 × 0.025-in, and 0.018 × 0.025-in copper-nickel-titanium aligning archwires, followed by 0.019 × 0.025-in stainless steel working archwires. Data collected at the start of treatment and after appliance removal included dental study casts, total duration of treatment, number of visits, number of emergency visits and breakages during treatment, and number of failed appointments. Sixty-two patients were recruited at the start of treatment, and the records of 48 patients were analyzed after appliance removal. Accounting for pretreatment and in-treatment covariates, bracket type had no effect on overall treatment duration, number of visits, or overall percentage of reduction in PAR scores. Time spent in space closure had an effect on treatment duration, and the pretreatment PAR score influenced only the reduction in PAR as a result of treatment. Use of the Damon3 bracket does not reduce overall treatment time or total number of visits, or result in a better occlusal outcome when compared with conventional ligated brackets in the treatment of extraction patients with crowding.