Download Orthodontic treatment timing in growing patients

C. Grippaudo, F. Pantanali, E. G. Paolantonio,
R. Saulle*, G. La Torre*, R. Deli
Postgraduate School in Orthodontics,
Università Cattolica del Sacro Cuore, Rome (Italy)
*Department of Public Health and Infectious Diseases,
Sapienza University of Rome (Italy)
e-mail: [email protected]
Orthodontic treatment
timing in growing
patients
abstract
Aim The aim of the study is to estimate the orthodontic
treatment timing for the main occlusal problems in
growing patients.
Methods Study design: a cross-sectional study was
carried out in Italian primary and secondary schools
from 2008 to 2011; 1375 males and 1642 females,
aged between 8 and 13 years, were visited. The sample
is divided into two main groups: primary school and
secondary school. Selected malocclusion signs were
registered according to an occlusal index (ROMA index) by
trained and calibrated operators. Prevalence of increased
overjet, Class III malocclusion, crossbite, deep bite and
open bite observed in each group are compared. A
significant decrease of prevalence with age is considered
a sign of spontaneous improvement of the malocclusion.
Results Descriptive analyses were performed using
frequencies, percentages and chi-square tests to
evaluate differences for categorical variables. The level
of significance was set at p ≤0.05. Data were analysed
with the software SPSS 19.0 for Windows. Class III
malocclusion, moderate or severe crossbite and severe
increased overjet and overbite seem not to improve
spontaneously.
Conclusion Early treatment of orthodontic problems
that do not improve with age may be helpful to avoid
worsening of the condition in permanent dentition.
Moderate Class II malocclusion and crossbite treatment
can be postponed.
Keywords Orthodontinc timing; Sagittal, Transverse
and Vertical discrepancies.
European Journal of Paediatric Dentistry vol. 14/3-2013
Introduction
The right timing and proper age to ideally commence
an orthodontic therapy has been long debated. In
particular, when the malocclusion is characterised by
alteration of jaw growth, there is a legitimate doubt
whether a dual-phase treatment carried out during
development of the occlusion is more beneficial than a
single-phase treatment performed at a later age when
the mouth is fully developed. However, despite the fact
that orthodontic treatment is widely carried out at an
early age, there is a lack of clear guidelines probably
because of the inadequate scientific evidence on the
effectiveness of some of these treatments.
Scientific literature on orthodontic treatment timing
of main malocclusions in all three dimensions of space
shows some controversies.
Transverse discrepancies – cross bites
In a prospective analysis on transverse discrepancies
between the two jaws, Kurol [1992] found that 45%
of the posterior crossbites with lateral mandibular
displacement resolves spontaneously with growth.
According to the author, despite the obvious functional
benefits of early correction of crossbites, the decision
to start early treatments depends on the severity of the
discrepancy and highlights the need to carefully assess
the cost-effectiveness of therapy. On the other hand,
the crossbite correction in deciduous dentition has
proven to be effective and permanent both in mixed
and adult dentition [Lindner, 1989; Thilander, 1984;
Harrison and Ashby, 2001].
Sagittal discrepa.ncies: Class II and Class III
malocclusions
In scientific literature, the crux of the debate on the
early treatment regards the sagittal discrepancies and
the need of a single or dual-phase treatment. Some
authors assert that, although in many cases satisfactory
results are obtained by early functional orthopedic
therapy, the overall result achieved with orthodontic
fixed appliance therapy alone is almost comparable
[Sweet, 2007; Harrison et al., 2007]. According to
other authors, early treatment of Class II malocclusion
reduces the severity of the discrepancy and also the
difficulty and length of treatment with fixed appliances
[King, 1999]. Although prospective controlled and
random studies are needed to properly evaluate the
effectiveness of the dual-phase therapy [King, 1990], it
would be crucial to find out which patients can benefit
more from an orthopaedic-functional treatment and
its correct timing with regards to the bone growth
[Tulloch, 1997].
Furthermore it is also advisable to detect Class III
malocclusions at an early age during the deciduous or
early mixed dentition [Baccetti, 1998]. The earlier the
treatment is carried out, the greater the chances of
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Grippaudo C. et al.
success, which results from skeletal changes rather than
dental compensation [Franchi et al., 2004], thus yielding
increased long-term stability of the outcome [Masucci
et al., 2011]. Treatment of Class III malocclusions should
also consider the jaw involved (upper jaw, lower jaw
or a combination of the two), genetic factors and the
growth pattern of the subject. In fact early treatment
is not universally applicable: in some individuals
the dentoalveolar compensation is indicated in full
permanent dentition, in others an orthognatic therapy
with surgical treatment of the skeletal discrepancy
might be needed at growth completion [Le Gall et al.,
2011; Kluemper and Spalding, 2001].
Vertical discrepancies: deep bite
and open bite
The debate on early treatment of skeletal vertical
discrepancies is even more controversial. The few
studies that have verified the effectiveness of the
orthodontic treatment (both single- and dual- phase)
on correction of increased overbite indicate that
the treatment produces a moderate improvement
followed by some degree of relapse [Simons and
Joondeph, 1973; Uhde et al., 1983; Schütz-Fransson
et al., 2006]. Franks found a marked improvement of
overbite after orthopedic-functional therapy although
this is due more to reduction of the interincisal angle
and improvement of the overjet rather than because
of the vertical growth of the mandible ramus [Franks
et al., 2011]. It should be underscored however that
a proportion of vertical growth occurs spontaneously
with the peak of pubertal growth, together with a
significant overbite reduction [Baccetti et al., 2011].
Therefore if orthodontic treatment is carried out at this
stage, it can intercept the growth acceleration resulting
in a shorter and more effective therapy.
Early treatment of open bite is very controversial,
probably because it is a multifactorial condition and
involves environmental factors, such as sucking dummies,
bottles and fingers, resulting in proinclined upper
incisors and protruded premaxilla, forward swallowing
[Larsson, 1994; Larsson, 2001], anterior open bite and
posterior crossbite [Warren et al., 2001; Castelo et al.,
2010; Melink et al., 2010], and mouth breathing, with
alteration of the craniofacial growth pattern [Harvold
et al., 1981] which is responsible for facial and tooth
features as long face, transverse contraction of the
upper palatal arch, gummy smile, both in dental Class
II and Class III skeletal base malocclusions [Harari et al.,
2010]. In fact the correct diagnosis of skeletal or dental
open bite is discriminatory in terms of the orthodontic
treatment. In subjects with average vertical patterns the
open bite is determined just by environmental factors
and can be treated more successfully during growth,
while in subjects with malocclusion associated with
increased skeletal vertical patterns the prognosis in
more unfavorable [Ngan et al., 1997, Grippaudo et al.,
232
2009]. Treatment options range from early correction
of habits to orthopaedic-orthodontic and combined
orthodontic-surgical treatments once the skeletal
growth is completed. Dental open bites respond well
to both mechanical and myofunctional early therapies
that can lead to a stable and full correction of the
initial malocclusion [Cozza et al., 2005] due to a good
restored orofacial muscular function. With regards to
skeletal open bite early treatments, according to some
authors the orthopaedic-functional therapy is effective,
especially in cases where the problem is worsened by
bad habits [Pellegrino, 2006; Fränkel and Fränkel, 1983;
Arat and Iseri, 1992; Ngan et al., 1992]. However, there
is no scientific evidence on the effectiveness of many
devices currently used for the orthodontic correction of
open bite [Lentini-Oliveira et al., 2007]. For this reason
the authors have not drawn clear guidelines on the
need of early orthodontic treatments until completion
of the permanent dentition. In order to establish the
effectiveness of treatment at an early age, it would be
necessary to collect age-related data on the incidence
and prevalence of malocclusions. In the present survey,
an Italian population aged 8-13 years is assessed with
the R.O.M.A. index [Grippaudo et al., 2007]. The
subjects were divided into age groups to estimate the
prevalence of malocclusions and to assess whether the
severity of malocclusions could be modified during the
mixed dentition phase. towards the full permanent
dentition.
Materials and methods
In this cross-sectional study, the R.O.M.A. index (table
1) [Grippaudo et al., 2007] was used to investigate 3017
Italian children, 1375 males (45.6%) and 1642 females
(54.4%) aged between 7 and 13 years. The sample was
balanced by gender, age and geographical area. The
survey was conducted between 2008 and 2011 and
the children 1529 (50.7%) from primary schools and
1488 (49.3%) from secondary schools−were examined
in their schools, after official approval of the survey by
each principal.
The ROMA index was performed by orthodontists
specifically trained with a ROMA index handbook,
in order to apply the index with same standards and
minimise errors. The index was already validated and
also verified for intra-examiner and inter-examiner
reproducibility [Grippaudo et al., 2007]. The intraexaminer reproducibility was tested comparing the
data of 20 children examined by the same operator
twice at one month interval. The inter-examiner
reproducibility was tested with the data of the same
group of 20 children collected by another operator.
The Kappa values were between 0.643 and 1.00 in
relation to the intra-operator agreement (0.00 < p <
0.002), and between 0.773 and 1.00 in relation to the
European Journal of Paediatric Dentistry vol. 14/3-2013
timing in Orthodontic treatment
inter-operator agreement (p = 0): the index is therefore
highly reproducible.
The purpose of this study was to estimate the
prevalence of increased overjet (2h, 3h, 4h of the
ROMA index), Class III malocclusion (4k, 3k), crossbite
(4n, 3n, 2n), deep bite (3r) and open bite (4p, 3p, 2p) in
the different ages and verify the problems which were
more frequent at the beginning of the mixed dentition
and at completion of mouth development. Knowing
which of these problems worsen, improve or remain
unchanged over time is useful for an indication of
the best timing for orthodontic therapies and to plan
screening and treatment services.
In January 2011 we closed the survey, with an
excellent number of responders.
Data were analysed with the software SPSS 19.0 for
GRADE 5
Systemic conditions A ME CONDITIONS, COME HANNO SCRITTO LORO NON CONVINCE. DIREI CONDITIONS. CONTROLLA PERO’
Malformation syndromes
Congenital malformations
5a
5b
Postural or orthopaedic conditions
Medic or auxological conditions
Genetic conditions of the jaws
4c
4d
4e
Facial or mandibular asymmetries
TMJ dysfunctions
Sequelae of trauma or surgery of the cranio-facial district
OVJ<0 mm (maxillary hypodevelopment or mandibular hyperdevelopment)
OVJ>6 mm (maxillary hyperdevelopment or mandibular hypodevelopment)
Mandibular hypo- or hyperdivergence
4f
4g
4j
4k
4h
4i
Scissor bite
Anterior or posterior crossbite >2 mm
Displacement < 4 mm
Open bite > 4 mm
Hypodentia of permanent teeth
4m
4n
4o
4p
4q
OVJ≥0 mm (maxillary hypodevelopment or mandibular hyperdevelopment)
3 mm <OVJ> 6 mm (maxillary hyperdevelopment or mandibular hypodevelopment)
3k
3h
Scissor bite
Anterior or posterior crossbite >2 mm
Displacement < 4 mm
Open bite > 4 mm
Hypodentia of permanent teeth
4m
4n
4o
4p
4q
0 mm <OVJ> 3 mm (maxillary hyperdevelopment or mandibular hypodevelopment)
2h
Anterior or posterior crossbite <1 mm
Displacement >1 mm
Open bite > 1 mm
Anomalies of the tooth eruption sequence
Poor oral hygiene
Normal mesial or distal occlusion (up to a cuspid) NON CAPISCO!
2n
2o
2p
2s
2t
2u
Functional asymmetries
Bad habits
Mouth breathing
2v
2w
2x
GRADE 4
Systemic conditions
Craniofacial conditions
Dental conditions
GRADE 3
Craniofacial conditions
Dental conditions
GRADE 2
Craniofacial conditions
Dental conditions
Functional conditions
GRADE 1
None of the conditions listed above
N
tabLE 1 ROMA index
European Journal of Paediatric Dentistry vol. 14/3-2013
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Grippaudo C. et al.
VARIABLES
PRESENCE OF PATHOLOGY n (%)
Primary School (%)
Increased overjet (h)
Class III malocclusion (k)
Crossbite (n)
Deep bite (r)
open bite (p)
Total of children
Total Sample
p VALUE
secondary school n (%)
590 (38.6)
142(9.3)
297(19.4)
308(20.1)
97(6.3)
1529
408 (27.4)
131(8.8)
248(16.7)
272(18.3)
102(6.9)
1488
3017
<0.0001*
0.64
0.04*
0.19
0.57
5a
*p<0.05 (level of significance)
tabLE 2 Distribution of the characteristics (h, k, n, r, p) without grades among primary and secondary school.
VARIABLES
Increased overjet
Class III malocclusion
Crossbite
Deep bite
Open bite
GRADE
4h
OVJ>6 m
3h
3 mm <OVJ> 6 mm
2h
0 mm <OVJ> 3 m
4k
OVJ<0 mm
3k
OVJ≥0 mm
4n
Crossbite >2 m
3n
Crossbite >1 mm
2n
Crossbite <1 mm
3r
Overbite > 5 mm
4p
Open bite > 4 m
3p
Open bite > 2 m
2p
Open bite > 1 mm
Total of children
PRESENCE OF PATHOLOGY n (%)
p VALUE
Primary School (%)
Junior High School
n (%)
114(7.5)
86(5.8)
0.064
248(16.2)
145(9.7)
<0.0001*
229(15)
177(11.9)
0.01*
28(1.8)
36(2.4)
0.26
115(7.5)
95(6.4)
0.22
113 (7.4)
77(5.2)
0.01*
140(9.2)
137(9.2)
0.96
44(2.9)
34(2.3)
0.30
308(20.1)
272(18.3)
0.19
10(0.7)
13(0.9)
0.48
53(3.5)
51(3.4)
0.95
34(2.2)
38(2.6)
0.55
1529
Total Sample
1488
3017
*p<0.05 (level of significance)
tabLE 3 Distribution of the characteristics (h, k, n, r, p) for each grade among primary and secondary school.
Windows.
Descriptive analyses were performed using
frequencies and percentages and frequency tables
for categorical variables. For the bivariate analysis chisquare tests were performed to evaluate differences for
categorical variables. The level of significance was set
at p ≤0.05
Results
Table 2 shows the results from the data collected from
primary and secondary schools in relation to increased
overjet (h), Class III malocclusion (k), crossbite (n), deep
bite (r) and open bite (p). There is a significant reduction
234
in the prevalence of the overjet increased with age (p
<0.0001), probably as a result of the physiological
sagittal growth of the mandible. There was also a
statistically significant reduction in the prevalence of the
crossbite increased with age (p <0.04). The decreased
prevalence of reverse overjet (Class III) (p = 0.64) deep
bite (p = 0.19) and the increased prevalence of open
bite with age (p = 0.57) are not statistically significant.
Table 3 shows the comparison between children of
primary and middle schools considering the severity of
the clinical signs (index scores 2, 3 and 4).
With regards to the sagittal discrepancies there is
a statistically significant reduction in the prevalence
of both mildly increased overjet (2h, 0 mm <OVJ> 3
mm, p <0.01) and moderately increased overjet (3h,
European Journal of Paediatric Dentistry vol. 14/3-2013
timing in Orthodontic treatment
3 mm <OVJ> 6 mm, p <0.0001) with age, while the
prevalence of the overjet greater than 6 mm (4h, p
= 0.064) does not show a significant reductio. The
reduction in prevalence of Class III malocclusion with
overjet ≥ 0 (3k, p = 0.22) and the increased prevalence
of Class III malocclusion with negative overjet (4k, p =
0.26) are not statistically significant.
With regards to transverse discrepancies there is a
statistically significant reduction of severe crossbite (4n,
anterior or posterior crossbite up to 2 mm, p <0.01),
whilst crossbite > 1 mm (3n) remain unchanged and
mild cross bite (2n, anterior or posterior crossbite <
1 mm) is reduced but these data are not statistically
significant (p >0).
With regards to vertical discrepancies there are no
statistically significant differences between elementary
and middle school children both with increased deep
bite (3r, p = 0.19) and increased open bite (4p, 3p, 2p,
p> 0).
Discussion
Timing of orthodontic care is a matter of great
importance in orthodontics. In paediatric patients in
particular, orthodontists have often argued whether to
commence therapies at an early age during the first
or early mixed dentition, or wait until all or most of
the permanent teeth are present. In this paper we
compared data collected with the ROMA index on the
presence/absence of malocclusion signs in two groups
of Italian children of primary schools (7 to 10 years) and
secondary schools (10 to 13 years). To estimate the best
timing for orthodontic treatment we calculated the
prevalence of conditions at different stages of growth
to verify the problems that were more frequent and
more severe at the beginning of the mixed dentition
compared to completion of occlusion development.
Sagittal occlusal relationships
The lower prevalence of increased overjet was found
statistically significant within all the total (scores 4h, 3h
and 2h together) and the overjet within 6 mm (scores
2h and 3h) with increased age of the subjects.
According to Tausche [2004] this might indicate that
the overjet can improve over time with the spontaneous
growth of the lower jaw and that early orthodontic
treatment is not necessary. Therefore in cases with
mildly or moderately increased overjet the orthodontic
treatment can be performed in a single-phase during
permanent dentition. However overjet > 6 mm (4h)
seems not to improve significantly. This can also be due
to the concurrent presence of bad habits or other causes
able to halt the spontaneous growth of the mandible.
In these cases an early orthodontic treatment might be
required because no further improvements are meant
to occur spontaneously and the condition could get
European Journal of Paediatric Dentistry vol. 14/3-2013
worse over time. Early treatments can achieve a more
predictable response especially in younger patients,
enhance self-esteem at young age and improve the
long-term stability of the results [Musich and Busch,
2007].
Regarding Class III malocclusion, the differences
between primary and secondary schools are not
statistically significant for both the reverse overjet and
the overjet ≥0 mm. This shows that in this malocclusions
the discrepancy does not change or improve with age
and an early orthodontic therapy is recommended
[Baccetti et al., 1998; Franchi et al., 2004; Masucci et
al., 2011].
Transverse Occlusal Relationships
When examining all crossbites (2n, 3n and 4n)
the prevalence is lower in children aged 10-13 than
in children aged 7-10 (p <0.04). When index scores
are considered separately, a statistically significant
reduction in prevalence is observed only for crossbite
≤ 2 mm (4n) and not between 0 and 1 mm (2n and
3n). It is possible that during replacement of the
deciduous teeth and buccal eruption of permanent
teeth some crossbites in mixed dentition might improve
spontaneously. Therefore not every crossbite in mixed
dentition need early treatments [Kurol, 1992] and the
clinician should assess the real therapy need for each
patient. For example, an early treatment is required
in the case of unilateral posterior crossbite with side
shifting of the mandible. If untreated, the crossbite and
the abnormal lateral movement of the mandible may
strain the orofacial structures, causing adverse effects
on the TMJ, the masticatory system and facial growth
[Petrén, 2011]. Therefore early treatments in mixed
dentition are usually undertaken to prevent those
conditions.
Vertical occlusal relationship
No differences between the two groups of
children were statistically significant with regards to
discrepancies on the vertical plane, either referred to
reduction of deep bite (3r) and open bite (4p, 3p, 2p).
This could mean that deep bite needs to be corrected
with orthodontics, as it cannot improve spontaneously,
and the bad habits, which are the cause of most of the
open bites, must be addressed at an early stage.
Conclusion
The best timing for orthodontic treatment continues
to be a controversial subject. The real benefits of early
treatment are constantly discussed, but at the moment
there are still very few studies on the topic. There is a
general consensus in the literature that early treatment
is indicated in cases of anterior and lateral crossbite,
Class III malocclusion, extreme forms of mandibular
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Grippaudo C. et al.
retrognathism and/or increased overjet. In the present
study there are some indications for early or interceptive
therapies. In fact Class III malocclusion, moderate or
severe crossbites and severe increased overjet and
overbite seem not to improve spontaneously. Early
treatment of these orthodontic discrepancies in
deciduous and early mixed dentition is intended to
avoid the development of more severe discrepancies
in the late mixed and permanent dentitions and can
shorten the treatment time or eliminate the need for
treatment at a later age.
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