Download Interceptive orthodontic care in Uppsala County Sarit Silkestrand

Institutionen för Odontologi
Medicine Magisterexamen i Odontologi
Master of Medical Science in Odontology
Interceptive orthodontic care in
Uppsala County
A retrospective study on frequency of interceptive
treatment, treatment approaches and
treatment providers
Sarit Silkestrand
Stockholm 2007
Nr 121
Interceptiv ortodonti i Uppsala län
En retrospektiv studie av frekvensen interceptiv behandling,
behandlingsmetod och behandlare
Sammanfattning
Bakgrund: Vid de två regionala specialistklinikerna i Uppsala län tillämpas olika
behandlingskoncept. I Region 1 som är en större tätort, sker den interceptiva behandlingen
rutinmässigt vid allmäntandvårdsklinikerna. I Region 2 som är en mindre tätort, sker den
interceptiva behandlingen oftare vid specialistkliniken.
Syfte: Att undersöka frekvensen av ortodontikonsultationer, den interceptiva behandlingen
vid allmäntandvårdsklinikerna samt att visa distributionen av ortodontiska behandlare i
Uppsala län. Material & Metod: Från tretton allmäntandvårdskliniker i Uppsala län
selekterades totalt 616 journaler systematiskt från patienter födda 1989. Ett protokoll
användes för att hämta in uppgifter från journalerna. Binomial fördelningsanalys
användes för att jämföra mellan regionerna samt mellan pojkar och flickor i grupperna;
icke-behandlade, allmäntandläkar-behandlade och specialist-behandlade.
Resultat: Fyrtio-åtta procent av patienterna erhöll ortodontikonsultation. Inga signifikanta
könsskillnader kunde påvisas vad gällde behandlingsgrupperna. I bägge regionerna
utförde glesbygdsklinikerna proportionellt mer interceptiv behandling jämfört med
stadsklinikerna i bägge regionerna (p<0.05). I Region 2 utfördes mer interceptiv
behandling vid specialistkliniken jämfört med vid specialistkliniken i Region 1 (p<0.01).
Konklusioner: På grund av de olika behandlingskoncepten vid de regionala
specialistklinikerna visar allmäntandvårdsklinikerna i bägge regionerna olika distribution
av ortodontiska behandlare. Även närhet till respektive specialistklinik föreföll påverka
både valet av behandlingsmetod och behandlare.
Handledare: Lena Berglund-Stevenberg och Eva Hellsing, Avd för Ortodonti, Institutionen för
Odontologi, Karolinska Institutet, Stockholm
Examinator: Professor, Anders Gustafsson, Avd för parodontologi, Institutionen för
Odontologi, Karolinska Institutet, Stockholm
Abstract
Background: At the two regional specialist clinics in Uppsala County different
treatment concepts are practised. In Region 1, a large urban area, the interceptive
treatment is routinely performed at the general dental clinics. In Region 2, a small urban
area, the interceptive treatment is more often performed at the specialist clinic.
Aim: To evaluate the frequency of orthodontic consultation, the given interceptive
orthodontic treatment at the general dental clinics and to show the distribution of
treatment providers in Uppsala County.
Material & Methods: From thirteen public general dental clinics in Uppsala County a
total sample of 616 records were systematically selected from patients born 1989.
A standardized protocol was used to collect data. Binomial test was used to compare
between the two regions and between girls and boys in the non treatment group, general
dental practitioner treated group and orthodontist treated group.
Results: Forty-eight percent of the patients received orthodontic consultation. No
significant gender differences were found concerning the groups. In both regions the
rural clinics did proportionally more interceptive treatment compared to the urban
clinics in both regions (p<0.05). In Region 2 more interceptive treatment was carried
out at the specialist clinic compared to at the specialist clinic in Region 1 (p<0.01).
Conclusions: Due to different treatment concepts at the regional specialist clinics, the
general dental clinics in both regions show different distribution of orthodontic
providers. In addition, proximity to respective specialist clinic appeared to influence
choice of orthodontic treatment and treatment provider.
Keywords
Interceptive orthodontics, Preventive orthodontics, Public dental service, Orthodontic
consultation, Sweden
Introduction
Definition of interceptive orthodontic treatment
Interceptive orthodontic treatment is generally defined as treatment aimed to eliminate
or reduce unfavourable ongoing signs of malocclusion, thus providing favourable
conditions for normal growth. In the literature it has been defined as “fostering
developmental changes which are favourable and halting or minimizing those that are
not” (Richardson 1999), “procedures that eliminate or reduce the severity of
malocclusion” (Popovich 1973) or “any treatment in the mixed dentition which will
prevent the establishment of a malocclusion” (Bass 1996).
The term preventive orthodontics can also be seen in the literature, which is similar to
interceptive treatment but is one step before, which means that the treatment is applied
prophylactic, for example using a space maintainer to prevent crowding. For simplicity,
in this study preventive orthodontics is also included in our definition of interceptive
orthodontics.
Treatment goal of interceptive orthodontic treatment
Unpredicted growth in the late adolescence or ectopic eruption of permanent teeth may
lead to the need of further treatment in the permanent dentition. Persisting habits may
likewise jeopardize treatment success. The orthodontic provider must be aware of these
factors and as well evaluate the patient’s compliance as many interceptive appliances
and methods rely entirely on the patient’s and parents’ cooperation (Wong et al. 2004).
Performed correctly, interceptive orthodontic treatment may reduce the risk for
developing facial asymmetry, functional jaw displacements, severe crowding and future
complex or prolonged treatment.
Interceptive orthodontic treatment is based on early detections of malocclusions
followed by orthodontic referrals or consultations for therapy planning. Knowledge of
normal dentofacial growth is fundamental for correct diagnosis and treatment planning.
It is not the main goal for interceptive orthodontics to achieve straight arches or perfect
tooth aligning, but rather to promote favourable dentofacial growth. Interceptive
treatment is performed in the mixed dentition. Growth adaptation of discrepancies in the
jaw relations using functional appliances during growth peak is often regarded as
interceptive treatment. Extractions to relieve severe future crowding starting in the
mixed dentition are an often-used interceptive intervention. Removable appliances are
frequently used as an interceptive measure but with these appliances only tipping
movements can be achieved. Severe discrepancies of jaw relations and crowding in the
permanent dentition are beyond the capacities of interceptive orthodontics. These
problems require comprehensive treatment and are often delayed until permanent
dentition is present.
Methods suitable for interception should be easy and cost-effective. For example:
grinding, extractions, removable plates, cross-elastics and lingual appliances such as
quad-helix. Other examples of interceptive treatment are, the simple and sometimes
forgotten methods such as behavioural management (for sucking habits), lip exercises
and spatula biting (for functional anterior cross bites). Space maintainers are often
included in interceptive treatment but since they have to be used for many years and this
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subsequently means long time of treatment resources, it can hardly be categorized as an
easy and cost-effective treatment.
Functional appliances are well documented in the literature and have best effect in Class
II malocclusions but it is questioned if they can be categorized as interceptive treatment.
By tradition functional appliances are often used in the general dental clinics but the
treatment goal to correct the over jet is not always reached and in one third of the
patients there is residual need for a second treatment with fixed appliance due to poor
treatment results or relapse (Follin et al. 1993, Rizell et al. 2006).
Most of the interceptive methods described above are dependent on existing growth and
can been seen as guidance for normal growth.
Review of the literature
The interceptive treatments should be confined to simple, mixed dentition cases to
ensure cost-effective results according to Kerr et al. (1996) who studied the use of
removable appliances in the Public Dental Service (PDS) in Scotland.
In a county in Sweden with sufficient specialist resources, a positive correlation to the
outcome of orthodontic care in children treated by both specialists and general dental
practitioners (GDPs) was shown. In counties with insufficient orthodontic resources
fewer and later treatments were started. To compensate for lack of resources more
treatments by GDPs were initiated and the outcome from these counties with less
resources resulted in reduced quality, especially the treatments by GDPs. As a result,
counties with lesser resources had higher persisting treatment need and higher desire for
further treatment (Bergstrom & Halling 1996).
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In Northern Ireland a study which aim was to test the effectiveness of interceptive
orthodontics in the general dental clinics showed, at the end of treatment in 9-11-yearold children who completed the interceptive treatment, a reduction in IOTN grades 4
and 5 from 69 percent at baseline to 42 percent (al Nimri & Richardson 2000). In this
study the authors used a specially designed plastic gauge (IOTN-gauge) to measure for
example over jet and the distance between the distal surface of the lateral incisor and the
mesial surface of the first permanent molar as a predictor for crowding and the need for
subsequent treatment. This is in agreement with conclusions made by Vakiparta et al.
(2005) who suggest that systematically applied early treatment contributes to a
reduction in later treatment need.
Orthodontic treatment need and malocclusions
Orthodontic treatment need in children has been reported to be one fourth to one third of
the studied population, see Table 1. These figures are based on varying definitions and
variables but altogether around one third of the children would benefit from treatment.
Permert and colleagues (1998) reported, that in their study of the children who were
seen by an orthodontist, 29 percent benefited from interceptive treatment without
appliances, that is by extractions and grinding alone. Prevalence of malocclusions in the
deciduous and mixed dentition where interception could be applicable is presented in
Table 2. According to al Nimri and Richardson (2000) the most favourable ages for
interception are between 9 and 11 years of age. These are ages in the mixed dentition
when both hard and soft tissues can advantageously be influenced. Also most dental
traumatic injuries occur in these ages (Borssen & Holm 1997). The most common
malocclusions and their contemporary treatments will be described briefly below from
an interceptive perspective.
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Table 1. Orthodontic treatment need in the deciduous and mixed dentition in different countries.
%
n
Age (yrs)
Index
Country
Authors
Al Nimri et al. 2000
Heikinheimo et al. 1987
Bassler-Zeltman 1998
Karaiskos et al. 2005
Heikinheimo 1978
Hannuksela 1977
Onyeaso 2004
Hosseini et al. 1999
Tausche et al. 2004
Linder-Aronson et al. 2002
Mugonzibwa et al. 2004
33
2,002
20.4
184
32
1,020
28
395
23.5
200
25.6
1,200
27
493
32
174
26.2
1,975
25.7
1,281
15.9
202
21.1
166
22.2
180
1. IOTN = Index of Orthodontic Treatment Need
2. FMB = Finnish Medical Board, 10-grade scale
3. SNBH = Swedish National Board of Health, 4-grade scale
4. IPION = Index for Preventive and Interceptive Orthodontic Needs
IOTN1
FMB2
SNBH3
IPION4
FMB
SNBH
IOTN
SNBH
IOTN
SNBH
IOTN
9-11
5
9
6-9
7
9
7-10
9
6-8
8-16
3-5
6-8
9-11
England
Finland
Germany
Kanada
Finland
Finland
Nigeria
Sweden
Germany
Sweden
Tanzania
Table 2. Prevalence of malocclusion in the deciduous and mixed dentition in different countries.
Authors
Thilander et al.
Stahl & Grabowski Keski et Bassler et
Schopf
Tschill et
2001
2003
al. 2003
al. 1998
2003
al. 1997
Country
Colombia
Germany
Finland Germany Germany
France
Dentition
Deciduous Mixed Deciduous Mixed
Onset
Mixed
Onset of Deciduous
of
Mixed
Mixed
n
373
2,910
1,225
7,644
486
1,020
2,326
789
Class II
15.5
Class III
2.9
Over jet
14.7
≥ 4mm
Overbite
18
≥ 4mm
Open bite
10.7
Posterior
7.2
cross bite
Crowding
17.4
n/r = not recorded
22.7
3.7
27.4
21
0.2
16.8
21
0.4
13.8
33
1.5
26.7
40
4
14
27
3.5
27
26
0.5
16.7
23.6
15
19
33.8
26.4
20.7
n/r
20.1
3.9
6.7
3.9
2.8
3.1
4.6
7.5
3.5
17
8.0
7.8
n/r
16
53.1
2.4
20
51
53.4
26.3
n/r
8
Crowding
Crowding is one of the most frequent orthodontic diagnoses. Signs of potential
crowding in the permanent dentition observed in the deciduous dentition are incisor
crowding, premature exfoliation and lack of approximal spacing. Good caries
prevention is fundamental to avoid extractions of severely decayed teeth and
consequently risk of space loss due to mesial drift. Most of the space loss (that is tooth
drifting) after premature loss of a deciduous tooth occurs within six months and is more
pronounced in the maxilla than in the mandible (Terlaje & Donly 2001, Richardson
1965, Northaway et al. 1994). It has been shown that losses of primary molars after 7.5
years of age had little effect on the relative space (Ronnerman 1977). In cases with risk
of severe crowding it is inadvisable to use space maintainers, as extractions will be
required later (Proffit 2000). Another study however, points out that predicting
crowding in the mixed dentition is difficult (Maj et al. 1979). According to the authors
where the lack of space for mandibular incisors exceeds 3.5 mm the results of nonextraction treatment were unsatisfactory (Maj et al. 1979). Approximal grinding as
guidance of eruption can be applicable in many cases, instead of comprehensive serial
extraction. Nevertheless, serial extraction can be beneficial and save later treatment time
in cases with severe crowding (Little et al. 1990). One should be reminded that although
extraction leads to relief of crowding it also reduces arch perimeter (Kau et al. 2004).
Therefore, extraction of lower primary canines to reduce incisor crowding may be
looked upon as a start of serial extraction. Other ways that does not involve extraction is
the lip bumper appliance. Several studies have documented lip bumper as a reliable
method to lessen mild to moderate crowding and for gaining arch length (Solomon et al.
2006, Davidovitch et al. 1997, Gerety 1997, Werner et al. 1994, Osborn et al. 1991,
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Murphy et al. 2003). However, the documentations of the long-term stability of the lip
bumper alone are scarce.
Later in the mixed dentition the use of headgear and expansion appliances may further
reduce crowding by space gain.
Cross bites
Cross bites occurs as anterior or posterior cross bites. Both types may also be associated
with mandibular sliding from retruded to intercuspid position, also called functional
cross bites. Prevalence of posterior cross bites has been reported to be about 11%
(Thilander & Myrberg 1973). The most common type is a single-tooth unilateral cross
bite whereas bilateral cross bite being the least usual type. The etiology behind the
malocclusion is considered to be sucking habits, occlusal interferences, nasal
obstruction and consequently mouth breathing (Larsson 1975, Corruccini et al. 1985).
There is a consensus among professional clinicians that cross bites, especially
functional cross bites, should be treated early (Kutin & Hawes 1969, Helm 1970,
Pirttiniemi 1994, Kennedy & Osepchook 2005, Castaner-Peiro 2006). Risks with
untreated cross bites are maxillary growth restriction, facial asymmetry and temperomandibular disorders (Egermark-Eriksson et al. 1990, Nerder et al. 1999). The latter
may be seen in patients chewing only on one side due to the cross bite, which can lead
to tempero-mandibular symptoms (Thilander et al. 2002).
An article by Castaner-Peiro (2006) points out the importance of correct diagnosis. The
article concludes that identifying between dento-alveolar and skeletal posterior cross
bites are essential in determining treatment approach.
Grinding, as an early treatment in the deciduous dentition appears to be the initial
treatment of choice. A study in the mixed dentition showed that grinding is most
10
effective when the maxillary inter canine width is 3.3 mm wider than the corresponding
width in the mandible (Lindner 1989). Under these circumstances the success rate was
90 percent according to the author. In a later follow-up study with the same subjects at
the age of twenty years, 57 percent of those who received grinding treatment showed a
stable correction of the cross bite (Tsaraptsani et al. 1999).
Spontaneous corrections of unilateral cross bites do occur after cessation of sucking
habits. Kurol and Berglund (1992) reported that in their study, that of the 3-5- year-old
children with cross bites in the primary dentition, 45 percent in the untreated group
showed spontaneous correction of posterior cross bites ten years later in the permanent
dentition. This spontaneous correction rate is much higher than the 21 percent and 17
percent reported by other authors (Thilander et al. 1984, Lindner 1989).
Grinding and expansion plates as treatment of unilateral functional cross bites in 4-yearolds had similar treatment success rates of 60 percent as in a 16-year follow-up study
(Larsson 1986). Kurol and Berglund (1992) reported that grinding alone had a success
rate of 64 percent (21/33). Later in the mixed dentition quad-helix and expansion plates
can be recommended. A recent review reports that an evidence-based conclusion can
not be drawn in determining which treatment modality is the most effective in treatment
of posterior cross bites (Petren et al. 2003). However, several studies included in the
review recommended the quad-helix because the authors found the appliance to be the
most cost-effective.
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Class II malocclusions
One of the most important reasons for treating a large over jet is the potential trauma
risk of the upper permanent incisors. Also the positive psychosocial impact with
reduced over jet should be reminded. Most dental traumas occur in 8-11-year-olds
(Borssen & Holm 1997). Over jets of more than 5 mm combined with incompetent lips
were found to have a significant correlation with trauma to the upper incisors (Andrup
et al. 1999, Jarvinen 1979, Burden 1995, Forsberg & Tedestam 1993). Other studies
have implied that due to changed ways of living for children today with less physical
activities and spending more time with computer games, the incidents of trauma have
decreased (Petti et al. 1997, Petti & Tarsitani 1996). These findings concern particularly
obese children, however, these obese children were less skillful and subsequently more
prone to trauma when they fell or sustained impacts compared to more physically active
children.
The ideal treatment timing for Class II malocclusions would be during the adolescent
growth spurt. Treatment is sometimes divided into two stages, where stage one aims to
reduce the over jet and stage two is comprehensive fixed appliances. Three large
randomised clinical trials of early two-stage versus later one-stage Class II treatment
have recently been published in the USA and UK. From these studies it can be
concluded that after the stage two treatment, there were no significant differences
between early two-stage treated patients and later one-stage treated patients in any
variable the studies evaluated. This means early treatment for Class II malocclusion is
not more effective or efficient, other than producing an early positive change in selfesteem, compared to later one-stage treatment (Wheeler et al. 2002, Tulloch et al. 2004,
Ghafari et al. 1998, O’Brien 2006). Ample evidence proves the effectiveness of
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functional appliances such as the Twin-block (Jena et al. 2006, O’Brien et al. 2003,
Illing et al. 1998, Dyer et al. 2001), Bionator (Jena et al. 2006, Illing et al. 1998, Jacobs
& Sawaengkit 2002), Teuscher activator (Singh & Thind 2003) and Bass (Illing et al.
1998, Cura & Sarac 1997). The problems with removable appliances are that the
treatment result is totally dependent on cooperation and this is very rarely fully
achieved. The treatment result with the Herbst appliance, which is a fixed functional
appliance, is remarkably better (O’Brien et al. 2003, Pancherz 1997). Of all the
removable functional appliances it should be noted that the Twin-block, due to its
unique two-piece design can be worn full time and thus have shorter treatment time.
Interceptive treatment in Sweden
In Sweden all dental treatment up to 19 years of age is fully subsidized by the
government. Interceptive orthodontic treatment is included. Prior to interceptive
orthodontic treatment it is common for the GDPs to have clinical consultations with
orthodontists. The GDPs initiate by selecting patients to these consultations. From the
assessment of orthodontic treatment need orthodontists decide which children to be
offered treatment. Less complex cases are in many counties treated by the responsible
GDP, whereas comprehensive treatment is referred to the specialist clinic. The choice of
interceptive method varies in different parts of Sweden. Generally, the most common
used appliances in general dental clinics in Sweden are quad-helix or removable
appliances to correct cross bites and functional appliances to correct Class II relations
(Josefsson & Halling 2000, Follin et al. 1993, Follin & Milleding 1994).
Unanimous usage of index of treatment need in Sweden does not currently exist.
Different counties have their choice of index. The most often used indexes in Sweden
are that of the Swedish National Board of Health and Welfare and the index of
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orthodontic treatment need (IOTN) which was originally developed by Brook and Shaw
(1989) (SBU). Similar to the view in the rest of the Nordic countries, the Swedish
public orthodontic care is in favour of early treatment to correct unfavourable growth
and trauma prevention in order to reduce further treatment need and thus costs.
The extension of prescribed interceptive treatment performed by GDPs is usually
determined by regional orthodontists but also based on the GDP’s knowledge and
interest. There is no national standard for prescribing interceptive treatment to GDPs.
Prevalence of orthodontic consultation and orthodontic treatment in Sweden has been
studied by several authors, see Table 3a-b. Table 3a shows that it is rather common with
orthodontic consultations, approximately half of the children had at some occasion
orthodontic consultation. The prevalence of received orthodontic treatment decreased to
approximately forty percent (Table 3b).
Table 3a. Prevalence of received orthodontic consultation in different counties in Sweden.
Authors
Received orthodontic
Age (yrs)
County
consultation (%)
Bergstrom et al. 1996
55
19, n=942
KronA SthlmB KoppC
Karlander & Kurol 2003,
48
19, n=223
Östergötland
Permert et al. 1998
Lagerstrom et al. 2000
46
19, n=1,554
Halland
A
Kronoberg, BStockholm, CKopparberg
Table 3b. Prevalence of received orthodontic treatment in different counties in Sweden.
Authors
Received orthodontic
Age (yrs)
County
treatment (%)
Bergstrom et al. 1996
37
19, n=942
KronA SthlmB KoppC
Karlander & Kurol 2003,
44
19, n=223
Östergötland
Permert et al. 1998
Mohlin et al. 2002
36
12, n=263
Bohuslän
A
Kronoberg, BStockholm, CKopparberg
14
Interceptive treatment in Uppsala County
Regarding interceptive orthodontic treatments in general, there are different treatment
concepts concerning where the treatment should be carried out, at a general dental clinic
or at a specialist clinic. Uppsala County has two regions with two specialist clinics.
Region 1 is a large urban area whose specialist clinic is responsible for the orthodontic
care of many clinics nearby and a few rural clinics. Region 2 is a small urban area and
has less orthodontic resources than Region 1 and provides care for only a few clinics.
Both specialist clinics are strategically located and are as well situated next to a general
dental clinic. The general dental clinics can additionally be sorted in urban and rural
clinics depending on proximity to the specialist clinic. The general dental clinics located
farther than 15 km from the specialist clinic are defined as rural.
The two regions in Uppsala County are practising different treatment approaches. In
Region 1 most of the interceptive treatments are routinely performed by GDPs. In
Region 2 nearly all interceptive treatment is carried out at the specialist clinic with aid
from orthodontic assistants.
No previous evaluation that especially focuses on the overall interceptive treatment in
Sweden can be found in the literature. The total percentage of initiated both interceptive
and comprehensive orthodontic treatment with appliances in Uppsala County in 2004 in
each age group was 24 percent (SBU). The extension of given interceptive treatment has
not been recorded earlier, nor the treatment provider, general dentists or specialists. This
knowledge can be useful when planning for orthodontic resources. For example
educating GDPs in interceptive orthodontics may need to be improved as demand
increases for such treatments. The significance of the location of the general dental
clinics in urban and rural areas with respect to proximity to the specialist clinic
15
regarding orthodontic treatment has neither been investigated earlier in Sweden. This
knowledge can show if there exists the same chances for children in urban and rural
clinics to receive orthodontic treatment.
The guideline for GDPs in Uppsala County in selecting patients and for orthodontists
when deciding which patients to give treatment is a modified variant of the IOTN. Thus,
the decision to show a patient for an orthodontist lies entirely on the GDP. Therefore, it
is paramount that GDPs are well educated in the IOTN.
Aims
The aims of this study are to:
•
evaluate the documentation of received interceptive orthodontic treatment by the
General Dental Practitioners in a randomly selected child cohort in the Public
Dental Service in Uppsala County
•
show the distribution of orthodontic treatment provided by General Dental
Practitioners in urban and rural areas
•
present the given treatments for interception provided by the General Dental
Practitioners in the Public Dental Service in Uppsala County
16
Materials and Methods
The design of this study was a descriptive retrospective cohort study.
This study was carried out at thirteen PDS clinics in Uppsala County, the 4th largest
province in Sweden with a population of about 300,000. Average number of children
per age group is about 3,000 (SCB). Percentage of each age group with a private dental
caretaker is estimated to 8.5 percent. These children were excluded from the study
population since their records cannot be found in the PDS clinics. The patients came
from both urban and rural areas.
Records from patients, born in 1989 on the 1st, 5th, 10th, 15th, 20th and 25th in every
month, were systematically selected. This generated a total of 653 records, 37 of them
had incomplete records and were excluded. Thus, this study consisted of the
documentation of 616 records. The records were examined for data from 3 years of age
in 1992 until 16 years of age in 2005, retrospectively. By the age of 16 all of the
interceptive treatment had been terminated. All data were collected by the same
examiner to rule out any variation error during collecting process. Data from both paper
records and digital records (since 2002/2003) were included. The sex distribution was
even, 321 (52%) boys and 295 (48%) girls.
The inclusion criterion was complete records during this period (3-16yrs of age). The
exclusion criterion was incomplete records.
Data from each record was obtained by using a standardized protocol, see Appendix.
The following categories were searched and recorded; gender, orthodontic diagnosis,
orthodontic consultation, given treatment, treatment provider and if possible treatment
results and need of further treatment. A patient could have been given more than one
treatment. Orthodontic consultation could result in one of the following; non treatment
17
(low treatment need and patients who declined), treatment by a GDP or treatment by an
orthodontist.
For this study, ethical consent has been obtained and approved by the Swedish Regional
Ethical Review Board in Stockholm (protocol number 2006/5:11).
Statistics
A sample size calculation for proportion (Wayne 2005) was carried out on the basis that
earlier studies have shown that the prevalence of received orthodontic consultations
would be about 45 percent (Table 3a). For a confidence interval of 5 percent and 99
percent confidence level the calculation suggests a total sample size of 539 records.
Binomial test (Abdi 2007) was used to test if there were any significant differences
between girls and boys in the no treatment group, GDP treated group and orthodontist
treated group. The null hypothesis was that there is no difference between boys and girls
in the groups. A significance level lower than 0.05 is accepted.
Binomial test was used to compare differences between Region 1 and 2. The null
hypothesis here was that there is no difference in distribution of orthodontic providers.
18
Results
Distribution of patients selected and sorted for orthodontic treatment with respect to
proximity to respective specialist clinic for both regions is shown in Fig. 1 and for
Region 1 and 2 separately, is shown in Fig. 2 and 3. In this study, the records revealed
that almost half of the children had at some occasion orthodontic consultation and
subsequently about one third received either interceptive or comprehensive treatment
(Fig. 1-3). It should be noted that a few children received interceptive treatment without
any orthodontic consultation and also a few children referred to the specialist clinic
resulted in no treatment (Fig. 1). Most of the patients selected for consultation received
one or two orthodontic consultations (range 1-6).
No significant differences were found between boys and girls either in the non treatment
group, the GDP treated group or the orthodontist treated group, thus the null hypothesis
is accepted.
In Region 2 more interceptive treatment was performed at the specialist clinic compared
to at the specialist clinic in Region 1 (Fig. 2 and 3) (p<0.01). Consequently, in Region 2
in the urban clinic, proportionally less interceptive treatment was carried out by GDPs
compared to the urban clinics in Region 1 (Fig. 2 and 3) (p=0.25). In Region 1 and 2 the
rural clinics did together proportionally more interceptive treatment compared to the
urban clinics in Region 1 and 2 together (Fig. 2 and 3) (p<0.05).
As for comprehensive treatment there was a tendency of a more generous attitude of
providing treatments to urban clinics in both regions (Fig. 2 and 3) (p<0.05).
This is in line with the different treatment concepts in the two regions in Uppsala
County regarding if interceptive treatment should be carried out at specialist clinics or at
19
general dental clinics. As a result, Region 1 and 2 show different distribution of
orthodontic providers and orthodontic treatment, thus the null hypothesis is rejected.
Of the patients who had consultations and ended up in the non treatment group, 14
(18%) were offered treatment but declined and 62 (82%) were assessed as having too
low treatment need to be offered fully subsidized orthodontic treatment by the PDS
(Fig. 1).
Of the patients who received treatment by GDPs, 81 (74%) (Region 1 (64/89) and
Region 2 (17/20)) had completed treatment as noted in the records, 14 (13%) (Region 1
(10/109) and Region 2 (4/109)) were in further treatment need and referred to the
specialist clinic and 14 (13%) had treatments which were discontinued prematurely.
The frequencies of different treatment methods used by GDPs after orthodontic
consultation in Region 1 and 2 are presented in Table 4. Table 4 shows that
proportionally more functional appliances were used in Region 1 compared to Region 2.
In the present study, percentage of received interceptive and comprehensive orthodontic
treatment with appliances was 30% (186/616) and without appliances 6% (40/616).
20
Total sample
population
n=616 (100%)
Region 1 n=506
Region 2 n=110
General dental practitioners
select 48% (298)
for
orthodontic
consultation
12% (76)
20% (126)
15% (96)
Non treatment
2% (13)*
Interceptive
treatment at
General dental
clinics by GDPs
2% (14)**
Referrals to
Specialist
clinic
1% (9)
Interceptive
treatment by
orthodontists
3% (21)
Comprehensive
treatment by
orthodontists
18% (110)
Figure 1. Orthodontic treatment flow in Region 1 and 2. The General dental practitioners (GDPs) first
select patients for consultation, then the orthodontists sort them into different groups. Numbers of
individuals are shown within parenthesis. Due to round up the given percentage may not add up evenly.
* Treatments by GDPs without orthodontic consultation. ** Further treatment need, referrals to
specialist clinic.
21
Region 1
n=506 (100%)
Urban clinics n=343
Rural clinics n=163
General dental practitioners
(GDPs) select 46% (235)
for
orthodontic
consultation
11% (56)
20% (100)
16% (79)
Non treatment
2% (10)*
Interceptive
treatment at
General dental
clinics by GDPs
3% (14)**
Referrals to
Specialist
clinic
2% (9)
Interceptive by GDPs
Urban
Clinics
9% (45)
[13%]
Rural
clinics
6% (30)
[18%]
Interceptive by
orthodontists
Comprehensive by
orthodontists
Urban
clinics
1% (6)
[2%]
14% (70)
[20%]
Rural
clinics
1% (4)
[2%]
5% (25)
[15%]
Figure 2. Orthodontic treatment flow in Region 1. The General dental practitioners (GDPs) first select
patients for consultation, then the orthodontists sort them into different groups. Numbers of individuals
are shown within parenthesis. Percentage of individuals in proportion to population of urban respective
rural clinics is shown within boxed brackets. Due to round up the given percentage may not add up
evenly. * Treatments by GDPs without orthodontic consultation. ** Further treatment need, referrals to
specialist clinic.
22
Region 2
n=110 (100%)
Urban clinic n=55
Rural clinic n=55
General dental practitioners
select 57% (63)
for
orthodontic
consultation
18% (20)
24% (26)
15% (17)
Non treatment
Interceptive by GDPs
3% (3)*
Interceptive
treatment at
General dental
clinics by GDPs
Urban
Clinic
5% (5)
[9%]
Rural
clinic
14% (15)
[27%]
Referrals to
Specialist
clinic
Interceptive by
orthodontists
Comprehensive by
orthodontists
Urban
clinic
7% (8)
[15%]
10% (11)
[20%]
Rural
clinic
3% (3)
[5%]
4% (4)
[7%]
Figure 3. Orthodontic treatment flow in Region 2. The General dental practitioners (GDPs) first select
patients for consultation, then the orthodontists sort them into different groups. Numbers of individuals
are shown within parenthesis. Percentage of individuals in proportion to population of urban respective
rural clinic is shown within boxed brackets. Due to round up the given percentage may not add up
evenly. * Treatments by GDPs without orthodontic consultation.
23
Table 4. Frequencies of treatment methods used by general
dental practitioners after orthodontic consultation in Region
1 and 2. Number of respective method is shown within
parenthesis. Due to round up the given percentages may not
add up evenly.
Region 1
n=79
Region 2
n=17
Treatment methods by GDPs
after orthodontic consultation
With appliances
Functional appliances
Removable appliances
Quad helix
Fixed lingual appliances
%
64
24
16
14
9
(50)
(19)
(13)
(11)
(7)
%
35
6
12
6
12
(6)
(1)
(2)
(1)
(2)
Without appliances
Extractions
Spatula biting
Grinding
37
27
6
4
(29)
(21)
(5)
(3)
65
47
6
12
(11)
(8)
(1)
(2)
24
Discussion
The prevalence of orthodontic consultations (48%) and received both interceptive
and/or comprehensive orthodontic treatment (37%) in this study are similar to the
findings of other counties in Sweden (Table 3a-b). The economic resources of the PDS
in most counties in Sweden restrict orthodontists from performing routine screening of
all children. A system where GDPs select patients for orthodontic consultation, like in
most counties in Sweden, can therefore give, as this study shows, a considerably high
chance to detect malocclusions and subsequently receive orthodontic treatment.
However, this system requires that the examinations are done by competent dental
personnel. This is not always the case. The consequences can for example lead to
missed ectopic upper permanent canines or result in showing too many low treatment
need patients, which both substantially consume resources.
Nearly all interceptive treatments in Uppsala County are preceded by orthodontic
consultations as very few patients received treatment without any consultation (Fig. 1).
This shows that the system previously discussed, in that aspect, is extensively followed.
The results concerning differences in distribution of orthodontic treatment and provider
in this study can be explained by the different treatment concepts in Region 1 and 2.
This study showed that these two concepts resulted in different treatment providers.
Region 1 distributes the interceptive treatment to the general dental clinics and Region 2
performs most of the treatment in the specialist clinic. Both concepts are, however,
dependent on the orthodontic consultations in order to detect malocclusions. The
advantages of providing interceptive orthodontic treatment at a general dental clinic
may be the shorter distance to the clinic and thus less time spent on travels. Also, for
this concept to be successful the treatments require competent providers with sufficient
25
supervision by orthodontists. Interceptive treatment at a specialist clinic is often
considered more effective and with shorter treatment time. Since the treatment at a
specialist clinic is performed with aid from orthodontic assistants it may also be
regarded as consuming less dentist/orthodontist resources. Future investigation of the
cost-effectiveness of these two concepts seems justified.
As a malocclusion can often be treated by more than one approach, orthodontists have
different ways of reaching the same result. An example is treatment of large over jets. In
Region 2 the urban general dental clinic had proportionally fewer GDP treatments
compared to the urban clinics in Region 1. However, a binomial test could not show a
significant difference (p=0.25), mainly due to large discrepancies in population sizes of
Region 1 and 2. In spite of that, the difference can partially be explained by that the
regional orthodontists in Region 2 often used fixed appliances for early reduction of
over jets and deep bites in Class II cases whereas the orthodontists in Region 1 preferred
functional appliances for the same malocclusions provided by GDPs. It was thus shown
that functional appliances are more commonly used in Region 1 than in Region 2. Since
the use of fixed appliance is not suitable for GDPs, this may answer for the low number
of treatments by GDPs in Region 2, especially in the urban clinic. It was also shown
that proportionally more interceptive treatment by GDPs was performed in rural clinics
compared to urban clinics in both regions (p<0.05). This might imply that rural clinics
take more responsibility for the orthodontic care because of the long distance to the
nearest specialist clinic.
The patients, who received interceptive treatment by GDPs but had a further need of
treatment, did not always imply that the treatments by GDPs were unsuccessful, the
26
patients might have another separate malocclusion which needed further attention and
they therefore were referred to a specialist clinic.
It should be noted that the patients who were offered treatment and declined, often
needed comprehensive treatment usually involving extractions and treatment with fixed
appliances at a specialist clinic.
Patients from the urban clinics in both regions received significantly more
comprehensive orthodontic treatment compared to patients from the rural clinics. The
reason for this is difficult to explain. It might be the same as for the interceptive
treatment; the proximity to the specialist clinic or that children living in a city see more
orthodontically treated peers and demand treatment more often.
Eighty percent of the non treatment group were considered having too low treatment
need. This might suggest that GDPs selected too many patients with low treatment need
due to uncertainty of treatment need or pressure from the parents’ side. It is also likely
that a malocclusion at the first consultation might have improved until to the second
consultation so that treatment was no longer indicated. On the other hand the patients
might have been selected too early which usually resulted in no treatment or a new
consultation at a more appropriate age. This is obviously resource-demanding.
However, on average, seven out of ten patients selected for orthodontic consultation by
GDPs did in fact receive treatment. Nevertheless, the GDPs selecting orthodontic
patients should be well educated in treatment need selection or more active in
consulting more experienced colleagues. Apart from treatment need selection, the
education should focus more on appropriate treatment timing.
In the present study, 74 percent of the patients who received treatment by GDPs had
completed treatment as noted in the records. This must be considered as a high rate. One
27
reason might be that in especially larger clinics, there is usually a GDP with a special
interest in orthodontics that takes care of the consultations and subsequent treatments.
Sufficient supervision by orthodontists may also have contributed to the results. In
Sweden, it has been shown that sufficient orthodontic resources are positively correlated
to outcome quality (Bergstrom & Halling 1996).
The reasons for drop-outs or prematurely interrupted treatment by GDPs were
inadequately recorded. Therefore no conclusions could be made regarding the cause for
drop-outs. It is likely that difficulties in co-operation, poor motivation and lack of
support at home have contributed to these drop-outs (Roberts et al. 1994).
The figures in the present study on interceptive and comprehensive treatment with
appliances and without appliances are similar to results from Bergstrom and Halling
(1996) who studied the orthodontic care in three Swedish counties.
It should be emphasized that the results from this study are entirely dependent on data
from the written records. Therefore, it is obvious that especially quality results need to
be interpreted with caution.
Conclusions
This study described the interceptive treatment and selection process in Uppsala County
and showed that:
•
Due to different treatment concepts between the two regional specialist clinics,
the general dental clinics showed different distribution of orthodontic providers
and orthodontic treatment. The different distribution was also depending on
proximity to respective specialist clinic.
28
•
Almost half of the children had at some occasion orthodontic consultation,
which implies that there is a high chance to detect malocclusions.
•
About seventy percent of the patients selected for orthodontic consultation
received some kind of treatment. This suggests that the GDPs’ orthodontic
assessments might have benefited from repeated education in orthodontic
treatment need and that it is important with continuous education to further
reduce showing low treatment need patients.
•
Eighteen percent received interceptive treatment by general dental practitioners.
In both regions extraction without any appliance was the most often performed
treatment. For the studied period, there seemed to be sufficient orthodontic
supervision as a high completion rate was recorded.
•
Compared to other counties in Sweden, Uppsala County showed similar values
in treatment with appliances and lower values for treatment without appliances,
and the distribution of orthodontic providers was also similar.
Acknowledgements
I am grateful to Lena Berglund-Stevenberg for her kindness, enthusiasm and infinite
help throughout this study.
Eva Hellsing for her invaluable advice regarding writing.
Siwachoat Srisuttiyakorn for his statistical support.
To my family for their understanding and tremendous support.
This study was supported by grants from Uppsala County Council.
29
Appendix
Protocol
For collecting data
Excluded:
Sex:
Clinic:
Personal number:
Orthodontic diagnosis
Sagittal:
Vertical:
Transversal:
Other: Crowding, missing, supplemental, ectopic eruption, asymmetry
No consultation
Treatment by GDPs
Consultation
Non treatment
Method
Completion
Treatment by GDPs
Treatment by orthodontist
Discontinued
Referral to orthodontist
Treatment method
Outcome
Completion
30
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