IN 101 IN

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Bernard Hemrend, DDS Gurkan Altuna, DDS Bryan Tompson, DDS

Orthodontics
SUMMARY RESUME
The authors of this article offer an Cet article veut initier le medecin au domaine de
introduction to the field of orthodontics. l'orthodontie. I1 presente les plus recents
developpements dans les appareils orthodontiques
They present the latest advances in et certaines consequences possibles du traitement
orthodontic appliances and some of the par orthodontie. L'article presente plusieurs cas et
possible consequences of orthodontic des exemples permettant au medecin de se
treatment. They discuss a number of cases familiariser avec certains des problemes les plus
and offer examples of some of the more frequents pour lesquels on fait appel a
common problems that the orthodontist is l'orthodontiste, comme par exemple la malocclusion
severe de classe II, la malocclusion division 1,
asked to treat. Such cases include severe l'orthodontie chirurgicale, le syndrome du <visage
Class II, division 1 malocclusion, surgical allonge>>, l'orthodontie adulte, le syndrome de
orthodontics, "long-face" syndrome, adult l'articulation temporo-mandibulaire, la periodontie,
orthodontics-TMJ-periodontics, late adult la croissance des dents de sagesse et les
growth, and post-retention changes. changements de post-retention. Enfin, l'article
souligne l'importance d'un bon equilibre entre les
Practical information useful to the physician informations pratiques qui seront utiles au medecin
who encounters patients with these lorsque confronte a ce type de patients dans sa
disorders is balanced with good research pratique et les donnees de recherche validant les
data to support the various claims. (Can Fam differentes affirmations.
Physician 1989; 35:933-944.)
Key words: Class II, division 1 malocclusion, surgical orthodontics, "long-face" syndrome
__.
Dr. Hemrend is Associate Professor of Toronto, 124 Edward Street, To- adult growth, and post-retention
of Orthodontics, Faculty of Dentistry, ronto, Ont. M5G 1G6 changes.
University of Toronto. He also
maintains a part-time orthodontic THIS ARTICLE OFFERS an in- Angle's Classification
practice in Toronto. Dr. Altuna is troduction to the field of ortho- of Malocclusion
Associate Professor, Orthodontics, dontics. It presents the latest ad- Let us first define the three differ-
Faculty of Dentistry, University of vances in orthodontic appliances and ent classifications of malocclusion.
Toronto. He also maintains a part- some of the possible consequences of The most commonly used method for
time orthodontic practice in Toronto orthodontic treatment. To illustrate classifying malocclusions into differ-
and Woodbridge. Dr. Tompson is this topic, we shall discuss a number ent groups is that of Angle. In a Class
Associate Professor, Orthodontics, of cases and offer examples of some I malocclusion, the buccal (back)
Faculty of Dentistry, University of of the more common problems that teeth occlude normally: that is, the
Toronto. He also maintains a part- the orthodontist is asked to treat. mesiobuccal cusp of the upper first
time orthodontic practice in Toronto. Such cases include severe Class II, di- molar occludes with the buccal
Requests for reprints to: Dr. Bernard vision 1 malocclusion, surgical ortho- groove of the lower first molar. In a
Hemrend, Faculty of Dentistry, dontics, "long-face" syndrome, adult Class II malocclusion, the mandibular
Orthodontic Department, University orthodontics-TMJ-periodontics, late buccal teeth occlude posterior to
CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 933
their normal position in relation to the Figure 1
maxillary buccal teeth. A Class II, di- Class 1, 11, & Ill Malocclusion and Crossbite
vision 1 malocclusion presents labially
protruded maxillary incisors, and a
Class II, division 2 malocclusion
presents lingually tipped or retro-
clined maxillary central incisors. In a
Class III malocclusion the mandibular
buccal teeth occlude anterior to their
normal position in relation to the max-
illary buccal teeth (Figure 1).
Normally the lower six anterior
teeth make light contact with the up-
per six anterior teeth in occlusion so
that the horizontal distance between
the upper and lower incisors (overjet)
is, on average, 2.5 mm, and the verti-
cal overlap of the upper and lower in-
cisors (overbite) is, on average, 2.5
mm. In addition, the labial and buc-
cal surfaces of the upper dentition,
and the lingual cusps of the upper
posterior teeth occlude within the oc-
clusal surfaces of the lower posteri-
ors, thereby avoiding a cross-bite
(Figure 1). If the patient presents ex-
cess overjet, excess overbite, anterior
open bite (i.e., insufficient overbite),
dental crowding or spacing, or devia-
tion from a normal Class I occlusion,
he or she may be referred to an or-
thodontist for further assessment.
The mid-line of the upper and lower
dentition as seen between the central
incisor teeth should coincide reason-
ably well with each other in occlusion
and with the mid-line of the face. If
they do not, an orthodontic assess-
ment should be made to determine if
there is an undesirable shift of the
mandible on closing because of the
interference of dental cusps, if the
mandible is not growing symmetrical- .A
ly, or if there is some other explana-
tion of the mid-line shift.
How Do Teeth Move with
Orthodontic Treatment?
Teeth lie in bony sockets that are
lined with soft tissue: the periodontal
ligament, which consists of collagen
fibres, ground substance, different
types of cells, blood vessels, and
nerves. During tooth movement the
orthodontic forces trigger a biological
response in the periodontal mem-
brane that causes the alveolar bone to
be resorbed on the compression side
of the teeth and deposited on the ten-
sion side. Thus bone, periodontal lig-
ament, and gingivae are continually
remodelled and re-organized in re-
sponse to orthodontic forces. Ideally,
934 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989
tooth movement should be obtained age wires) have reduced the formerly * The advent of Hanson's Speed
by means of light forces, with minimal time-consuming task of intricate wire brackets is a further time-saver, elim-
damage to the periodontium; it should bending. These new flexible "memo- inating the need for individually tying
occur at an optimal rate, with little pa- ry" wires help the orthodontist to each bracket to the archwire.
tient discomfort. keep the amount of force exerted in
the optimal range. They aid in pre- Studies of Some
Orthodontic Appliances venting the use of excessive force and Possible Consequences of
There are two types of orthodontic so help to facilitate tooth movement Orthodontic Treatment
appliances: removable and fixed. A and minimize root resorption.
limited number of simpler orthodon- * Recent esthetic advances have in- Orthodontic appliances
tic cases can be treated by means of corporated the use of lingual brackets and decalcification
removable appliances alone, but such that are placed on the lingual surfaces The presence of demineralization,
appliances are inappropriate for com- of the upper and lower teeth and so often referred to as "decalcification"
plicated cases. Fixed appliances de- are invisible. Because of added diffi- or "white spots", following the re-
pend on the use of brackets placed in culty and problems that most ortho- moval of orthodontic appliances, has
precise position on the teeth and on dontists experience in using the lingu- been accepted as one of the possible
archwires tied into the brackets for al mechanics and the increased chair hazards of orthodontic treatment.
the application of force. time involved in changing archwires, The presence of orthodontic appli-
lingual brackets are primarily used in ances in the mouth makes oral hy-
Advances in select adult patients and in relatively giene more difficult and predisposes
Orthodontic Appliances simple cases. The use of lingual the patient to the accumulation of
A number of advances have recent- brackets considerably increases the more plague.1'2 Maxillary lateral inci-
ly been made in orthodontic appli- cost of treatment. sor, and the madibular canine first
ances. These include the following: * Metal brackets are most commonly premolar and molar, are more sus-
* An acid-etch resin-bonding system used, although clear plastic brackets ceptible to the formation of white
has largely replaced the use of a large are often used on the maxillary ante- spots.3'4 Areas of demineralized
cemented metal band and bracket rior teeth in select cases (Figure 2.) enamel may, in time, either progress
around every tooth. Instead, ortho- Most recently, ceramic brackets have to caries or remineralize, depending
dontists can now use simple bonded been introduced into clinical ortho- on the severity and site of the lesion.9
brackets that are much smaller than dontics. These are much stronger A number of studies have shown that
bands and more esthetically pleasing. than the clear plastic brackets and with good oral hygiene and a continu-
* The advent of Andrews' straight- less prone to distortion by wire ous fluoride program, decalcification
wire appliance has allowed tip, forces. Since these brackets blend in of labial surfaces of teeth during or-
torque and rotation to be built into with the tooth colour, many adult pa- thodontic treatment will be signifi-
the brackets. The use of straight tients choose to wear them. There cantly reduced to the levels of non-
wires makes treatment easier for both may, however, be problems with the orthodontic patients.2'4'5'6
the orthodontist and the patient. removal of some of these ceramic Orthodontic appliances and caries
* The new advances in wires (space- brackets at the present time. Studies have shown that the indi-

Figure 2
Severe Class 11, Division 1 Malocclusion, Pre-Treatment

CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 935

vidual's caries rate is directly related are removed. By contrast, a small presence of thin, attenuated, incisor-
to the extent of oral hygiene practised: proportion of patients (about 10%) root apices prior to treatment may
individuals who practise poor oral hy- experience considerably more dam- give rise to concern about resorption
giene are more susceptible to caries age. These studies further showed during orthodontic treatment.n
than are those with good oral that orthodontic treatment caused no Long-term studies indicate that apical
hygiene.7'8 significant alveolar bone loss.'4 In ad- root resorption usually ceases at the
Orthodontic appliances and stains dition, long-term studies show that termination of treatment, 23 and that
In an extremely small number of orthodontic therapy during adoles- orthodontic treatment does not nor-
cases, black and green stains, associ- cence does not extend the period of mally cause a clinically significant
ated with direct bonded brackets, de- periodontal health.15 shortening of the roots. A study con-
velop on the enamel surface of the Orthodontic appliances ducted by Ronnerman and Larsson
teeth because of corrosion of the and root resorption showed that root resorption of 1 mm
stainless steel brackets at welded and Some root resorption may occur -3 mm was apparent on a least one
soldered points.10'11 during orthodontic treatment. The of the upper incisors in 39% of an or-
prevalence and amount of root re- thodontically treated sample of 23 pa-
Orthodontic appliances and gingivae tients, and that this root resorption
The gingival condition most com- sorption varies widely and may de-
pend on a number of factors, includ- did not progress for many years fol-
monly associated with orthodontics is ing the choice of criteria used to lowing treatment.24
a mild gingivitis, even in patients with measure resorption, the type of appli-
excellent oral hygiene.12 This is be- ance and forces used, the extent of
Orthodontic Treatment
cause of the many plaque-trapping the tooth movement, and the dura-
in the Primary Dentition
areas created by orthodontic appli- tion of active treatment. Root resorp- As a general rule, little if any or-
ances. Most children develop a mod- tion is also reported in teeth that havethodontic treatment is done in the pe-
erate hyperplastic gingivitis within not been treated orthodontically.16 riod of primary dentition (from age
one to two months after appliances Even though the etiology of external two to six or seven). If, however,
are placed.6 Gingivitis is a reversible root resorption is not completely there are occlusal interferences which
condition, but it can also lead to de- understood, the following factors cause the mandible to be displaced
structive periodontitis in patients with have been identified as causative: from its normal path of closure, these
poor dental hygiene. Whether or not may be corrected at this stage. Space
gingivitis after orthodontic treatment * periapical inflammation;17'19 may be maintained, if indicated,
has led to any permanent damage is * excessive orthodontic or occlusal when deciduous teeth are lost prema-
best determined by an assessment of forces (trauma);16-2' turely. These conditions should be
loss of attachment and alveolar bone * tumours and cysts;18"19 diagnosed and treated by the family
height reduction.13 Zachrisson's stud- * pressure from apposing impacted dentist, the pedodontist, or the or-
ies showed, however, that most or- teeth;17-19 thodontist. Children with more se-
thodontic patients experience little or * idiopathic cause or individual pre- vere problems, such as cleft lip and
no damage to the attachment, and disposition to root resorption.17'20'22 palate, ankylosis of the temporoman-
that the gingival health returns to Clinically, also, the pre-treatment dibular joint (TMJ), and other cranio-
normal after the bands and brackets presence of root resorption and the facial anomalies, should be sent for

Figure 3
Orthodontic Headgears, Bite Plate, and Blonator

936 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989

consultation to a specialist or hospital erupted. It will vary in length de- bite plate is worn at the same time, it
team capable of diagnosing and plan- pending on the particular case, but will help to reduce the overbite.
ning treatment for such patients at a usually from one to two years to com- During the first stage of treatment,
very early age. plete. many orthodontists use a removable
The purpose of the first stage of functional appliance instead of, or in
Orthodontic Treatment in treatment is to correct the rather se- addition to, a headgear. There are
the Mixed and Permanent vere disharmony between the two many kinds of functional appliances,
Dentition jaws and between the upper and low- but the more common ones are the
er dentition, and to reduce the pro- bionator, the activator, and the
Most orthodontic treatment is car- trusion of the upper incisors and the Frankel appliance. Although each
ried out during the period of mixed deep overbite, and thereby promote has its own specific make-up, there
and permanent dentition. We shall a natural lip seal. This is generally are a number of common principles
examine some cases representative of done with a minimum of appliance underlying the use of a functional ap-
those of the physician, the pediatri- therapy, by means of simple appli- pliance that the orthodontist must
cian, the dentist, and the pedodontist ances, since the second stage of treat- know, as the incorrect use of an ap-
may encounter, and discuss how ment usually requires the bonding of pliance can make a patient's condi-
these patients can be best treated and brackets to all permanent teeth. tion worse. The purpose of a func-
the optimal point at which to refer Orthodontic appliances commonly tional appliance is similar to that of
them for an orthodontic consultation. used during the first stage of treat- headgear, although a functional ap-
Class II, division 1 ment are headgears and bite plates pliance can more selectively control
The patient seen in Figure 3 is nine (with or without brackets on the four the vertical eruption of the different
and a half years old and presents a se- incisors, depending on the patient's segments of the upper and lower den-
vere Class II, division 1 malocclusion. need) or functional appliances (Fig- tition, while normally allowing less
What type of orthodontic treatment ure 4). The headgear is visible and is posterior movement of the maxillary
is required for a patient presenting usually worn 12 to 14 hours out of dentition and the maxilla.27 Some
with such a malocclusion, and at what evety 24 hours, whether or not the cases are more amenable to treat-
time is it best to start treatment? patient is asleep; it is not worn during ment with a functional appliance than
If the malocclusion is as severe as active play or sports. The patient is are others, depending on a number of
that of this patient, treatment is best instructed not to remove the head- factors, and the orthodontist should
accomplished in two stages. The first gear from the braces without first dis- make the assessment necessary for
stage, which may take approximately connecting the elastic or spring force, case selection.
one year to one and a half years to and allow anyone to play with or to Functional appliances are made of
complete, should be started when the pull the headgear, as the headgear acrylic and are removable by the pa-
child is about nine or 10 years of age, could spring back into the cheeks or tient. They are constructed to ad-
even though he or she still has many eyes and cause severe damage. Its vance the patient's mandible and to
deciduous teeth. A second stage of purpose is to restrain the forward and lower it vertically. The patient is
treatment is usually required when downward growth of the maxillae and asked to wear the bionator full time,
the child reaches 12 or 13 years of the maxillary dentition while the except during meals, and this appli-
age, after all permanent teeth have mandible continues to grow.25;6 If a ance is small enough and comfortable

Figure 4 Figure 5
Patient Seen in Figure 2, Patient Seen in Figure 2, after Second Stage
after First Stage of Orthodontic Treatment
of Orthodontic Treatment

CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 937

enough to allow the patient to wear it Some clinicians use a functional ap- mans has shown that the mandible
and to talk with it without discomfort. pliance because they consider that it may grow 1 mm to 1.5 mm longer in
The activator is a bulkier appliance; may cause a patient's mandible patients who use the activator than in
the patient is asked to wear it three to to"grow" beyond its normal growth members of a control group, but this
four hours a day and during sleep. potential.-I Although there is lack of growth is not clinically significant.32
Some clinicians may prefer that Class agreement on this point, and al- The functional appliance is capable,
II patients use a headgear if their max- though McNamara has shown evi- however, of producing an excellent
illary lip and dentition are very protru- dence of such extra growth in experi- result in the right cases, and the or-
sive, or if there is a need to distalize ments in which he advanced the thodontist can best make the proper
the maxillary posterior dentition to mandible in monkeys,31 consensus of case selection. If the first stage of
gain more arch room. A bionator may orthodontic opinion does not sub- treatment has been successful, the
be preferable for patients whose prob- stantiate this possibility in humans.32 antero-posterior disharmony between
lem is more one of mandibular retrog- Such good growth, in fact, may also the two jaws and the dentition will
nathism. A headgear and a functional be seen in unrelated youngsters dur- have been reduced sufficiently to
appliance are often used simultane- ing pubertal growth acceleration. achieve a more normal antero-poste-
ously when both conditions are Vargervik and Harvold's excellent re- rior occlusion along with an improved
present.28,29 search study on the activator in hu- overbite (Figure 5), allowing the or-

Figure 6
Mandibular Advancement Surgery and Orthodontics
to Restore Balance to Jaws

938 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989

thodontist to achieve a predictably facial growth and its clinical implica- dontist's prediction of whether the
good Class I occlusion at the second tions and should make treatment de- young patient's permanent teeth are
stage of full-bonded orthodontic treat- cisions on the basis of the individual likely to be mildly or severely crowd-
ment, when all permanent teeth have patient's needs. ed when they fully erupt at age 12.
erupted. The second stage of treat- The assessment itself is based on
ment is usually, though not always, Treatment Timing and many factors besides the mixed denti-
necessary to achieve an excellent re- Dental Crowding in the tion analysis.
sult, as functional appliances are not This is an important assessment, as
capable of carrying out detailed tooth Period of Mixed entition it will determine the best time to start
movements such as rotations and A youngster of seven or eight who treatment, as well as the type of treat-
torque (Figure 6). presents crowding of the incisor teeth ment indicated. It may prevent the
or insufficient room for some of the eventual extraction of permanent side
Class II Treatment Timing incisors to erupt should be sent to an teeth during orthodontic treatment in
and Degree of Disharmony orthodontist for assessment. The key some patients. In others it may pre-
between the Jaws to this assessment lies in the ortho- vent severe crowding of teeth by
The orthodontist may be asked, means of properly timed serial ex-
"What will happen if you do not do tractions. Again, the orthodontist
the first stage of treatment? Can you should decide whether or not to ex-
still get a good result with full braces tract a young patient's deciduous cus-
later, when the patient is 12 or 13 Figure 7 pids to make room for crowded per-
years of age?" Severe Class IlI Malocclusion, manent incisors, since this procedure
The answer to this question de- Requiring Surgery is indicated in some instances and
pends on the severity of the antero- and Orthodontics strongly contraindicated in others.
posterior or the vertical disharmony
between the two jaws, or on the se- Timing and Surgical-
verity of the Class II dento-alveolar Orthodontic Treatment
malocclusion. If the orthodontist be- Some patients require both a surgi-
lieves that by delaying treatment he cal and an orthodontic approach (sur-
will have a difficult time achieving a gical orthodontics). Occasionally, a
Class I correction, he is best advised youngster with Class II, division 1
to do two-stage treatment. In addi- malocclusion and a small mandible
tion, the degree of lip incompetence may present a mismatch between the
caused by maxillary dento-alveolar size and/or position of the two jaws
protrusion, and the possibility of frac- which is so severe that the orthodon-
ture to the maxillary incisors during tist may elect to postpone treatment
play, will influence the orthodontist's until the patient has completed all or
decision on early treatment timing. If most of his or her growth. The ortho-
the Class II disharmony is not too se- dontist will then embark on a com-
vere, the orthodontist may elect to bined surgical-orthodontic approach,
delay treatment until the patient is 11 whereby an oral or maxillo-facial sur-
or 12 years of age, and to undertake geon will lengthen the mandible surg-
one stage of full-bonded treatment at ically in order to restore the balance
that time. between the two jaws (Figure 7).
Sometimes males presenting a There are cephalometric and matu-
Class II, division 1 malocclusion are rational standards which the ortho-
treated too early, and as a result their dontist may use to assess the degree
treatment time is prolonged. At age and sites of disharmony present be-
10 the mandibular growth rate of the tween the jaws.34 36 The orthodontist
"average" male slows down, and pro- may elect to try early first-stage or-
vided that the skeletal disharmony is thodontic treatment during such a pa-
not so severe as to require earlier tient's growing years in the hope of
treatment, the orthodontist contem- avoiding surgery. If the patient's re-
plating two-stage treatment may be sponse to orthodontic treatment is
wise to delay treatment until the pa- unfavourable, however, surgical-
tient reaches the age of 11 and a half orthodontic treatment will be neces-
or 12, when his pubertal growth ac- sary if the patient wishes to achieve
celeration may be starting. The or- an excellent result both occlusally
thodontist can best assess the likely and facially. The surgery is usually
growth accelerations, as well as the not performed on females before
patient's maturational status, if nec- they reach the age of 15 or 16 years,
essary, before making a decision or on males before the age of 17 to 18
about treatment timing.33 The ortho- years. There is a certain amount of
dontist must thoroughly understand full-bonded orthodontic treatment to
CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 939
 B-
be carried out prior to surgery in most anasal regions and genioplasty to rate from the outset and work as a
such cases, and this may be started soften the chin area. Such surgery is team in both the diagnostic and timed
about one to two years prior to the an- best done at the completion of facial treatment procedures. Without this
ticipated date for surgery. growth, for if mandibular surgery for collaboration, problems can occur
As part of the surgical procedure such a patient is performed during that may result in a very unsatisfacto-
on the mandible, the patient's jaws the growing years, the mandible may ry occlusal and esthetic result.
are usually wired together for a peri- continue to grow excessively long,
od of approximately eight weeks, and the patient may need another op- Excess Lower-Face Height
during which time he or she is re- eration at the completion of active fa- and the "Long-Face"
stricted to a soft diet. However, re- cial growth. A child who presents Syndrome
cent advances in surgical technique with Class III malocclusion should be The patient seen in Figure 9
eliminate the need for wiring the jaws sent to the orthodontist during the presents a disfiguring malocclusion.
together and thus permit the patient early, growing years, to enable the This type of case is characterized by a
to open his mouth immediately after orthodontist to gather his or her long lower-face height, inability of
surgery. This technique of rigid fixa- records and make a differential diag- the lips to meet at rest without men-
tion is relatively new, however, and nosis relating to the timing and type talis muscle strain, excess upper-inci-
requires skill and experience on the of orthodontic treatment necessary, sor exposure and, often, a large verti-
part of the oral and maxillo-facial sur- and the possible need for a later sur- cal space between the upper and
geon. gical-orthodontic approach, as many lower incisors, known as "anterior
After inter-maxillary fixation (wir- Class III cases can be handled with- open bite". This "long-face" syn-
ing of the jaws) is discontinued, the out surgery. drome may be caused by the genetic
orthodontic treatment is continued. It Not all Class II and Class III pa- arrangement of the facial bones, or it
can usually be completed in three to tients undergoing surgical orthodon- may develop as a result of the pres-
six months if the surgical result is sat- tics require the type of surgery de- ence of a nasal or naso-pharyngeal
isfactory. If it is not, orthodontic scribed in the previous two cases. obstruction, which has led to chronic
treatment may take longer to com- Often, surgery is carried out in the mouth-breathing. Enlarged adenoids
plete, and if during surgery, the sur- opposing jaw, and sometimes two- in relation to the size of the naso-
geon has not positioned the mandibu- jaw surgery is required for successful pharyngeal airway38 are a local envi-
lar condyles in the fossae and the treatment. Careful diagnosis and ronmental factor that could cause
mandible relapses significantly post- treatment planning are essential: in chronic mouth-breathing. Often a
surgically, a second surgical proce- all cases requiring a surgical- combination of genetics and environ-
dure may be required to obtain a sat- orthodontic approach, the orthodon- ment is present. It is important to rec-
isfactory result.37 tist and the oral-or maxillo-facial sur- ognize that such an environmental in-
Although surgical lengthening of geon familiar with the many intrica- sult, if chronic and if severe enough
the mandible is best performed at the cies and possible pitfalls specific to to lead to chronic mouth breathing,
completion of active facial growth, it orthognathic surgery should collabo- may alter the patient's facial growth
may be considered at a much earlier pattern vertically and make the mal-
age if a child's facial deformity is so occlusion worse during the active
severe that it may cause psychological Figure 8 growth years.38 Such a patient should
damage as he or she grows older. If A Disfiguring Malocclusion, be referred to the orthodontist for as-
the surgery is performed early, how- "Long-Face" Syndrome sessment at an early age,39 preferably
ever, the mandible, although continu- during the early mixed dentition
ing to grow, does not attain normal I years. The orthodontist will assess
size, while the rest of the face contin- the patient clinically, using a lateral
ues to grow normally. If, at the com- and postero-anterior cephalogram
pletion of the active facial growth and, if indicated, will refer him or her
process, the patient again has a badly to an otolaryngologist for ENT exami-
retrognathic mandible relative to the nation. The orthodontist will explain
rest of the face, he or she may require the findings and the concern that the
a second surgical procedure to naso-pharyngeal obstruction may be
lengthen the mandible. The patient causing a deleterious vertical growth
and the parents should be forewarned pattern that will not allow successful
of this possibility. orthodontic treatment of the patient's
Figure 8 shows an adult with severe malocclusion or facial esthetics. The
Class III malocclusion and a prog- patient's case history and the oto-
nathic mandible. This patient re- laryngologist's complete naso-
quired a combined surgical- pharyngeal clinical examination, ex-
orthodontic approach whereby the amination of the cephalometric head-
mandible was surgically shortened films, and airflow tests, when indicat-
during treatment to provide the de- ed, to assess the effect of the nasal or
sired result. In addition, this patient naso-pharyngeal obstruction on the
received a proplast augmentation to patient's nasal resistance,40 will deter-
build out the flattened maxillary par- mine whether there is need for surgi-
940 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989
cal removal of the obstruction. Such lergies did not alter facial growth pat- provement in the growth pattern of
surgery is best done at an early age terns in allergic children with airway the face.
while the patient is growing rapidly in obstruction.42 Bresolin and colleagues Thus, orthodontists believe that
order to obtain the maximum correc- state that "longitudinal studies are the youngster with airway obstruction
tion during the remaining period of needed to evaluate the effectiveness and chronic mouth-breathing, and a
growth. Linder-Aronson and Wood- of early intervention in preventing long lower-face height or tendency to
side have shown that the surgical re- these growth alterations" in mouth- same, should be promptly examined
moval of enlarged adenoids resulted breathers with perennial allergic and diagnosed by an otolaryngologist
in a marked self-improvement in the rhinitis.42 and/or an allergist and pediatrician.
facial and dental growth pattern in Some clinicians believe that there Often a hospital team or a combina-
some individuals;39 the key reason for is no conclusive evidence that en- tion of specialists is required to make
this improvement in the naso- larged lymphoid tissue causes a dele- the best assessment.4546 Indeed, the
pharyngeal obstruction and the subse- terious facial growth pattern,43 while decision to advise adenoidectomy is
quent change from mouth-breathing others, such as Bluestone, have con- often a difficult one, since some chil-
to nasal breathing. cluded that "children with persistent dren may continue as habitual
Other environmental factors which nasal obstruction due to adenoids, mouth-breathers even after adenoi-
may lead to this type of malocclusion and not to infection or allergy, (may dectomy, and some children with
and "long-face" syndrome are swell- possibly) benefit from their unobstructed airways and normal na-
ing of the nasal mucosa as a result of removal."44 Bluestone attributes this sal resistance have mouth-breathing
allergy or nasal obstruction caused by benefit to improved functioning of or "adenoid facies."40 In a child with
other disorders in the nasal cavity.41 the nasal airway and improved nasal allergy, adenoids may recur
Bresolin and colleagues showed that speech, even though he considers after they are removed. Only partial
a sample of chronically allergic that current scientific evidence is in- adenodectomy may be advised in
mouth-breathers, when compared to sufficient to provide certainty. He cases of velopharyngeal insufficiency
a sample of nose-breathers with no further states that the benefit of re- where enlarged adenoids are
nasal obstruction or allergic rhinitis, moving enlarged tonsils "in the hope present.47 On the other hand, the sta-
had longer faces, more retrognathic of improving a dentofacial abnormali- bility of orthodontic results has
jaws, steeper mandibular planes, nar- ty has not been proven."44 In a recent seemed to be enhanced by removal of
rower maxillae, and more retroclined investigation, Behlfelt and Linder- respiratory obstructions and the at-
maxillary and mandibular incisors. Aronson, however, showed that tainment of normal nasal breathing
These findings are similar to those of when the tonsils were large enough to and correct patterns of deglutition.47
Linder-Aronson in an adenoid-ob- meet in the mid-line, they caused air- It seems reasonable that if ENT ex-
structed sample.41 When the cause of way obstruction which led to chronic aminations of an orthodontic patient
chronic mouth-breathing is nasal al- mouth-breathing and to a vertical disclose very enlarged adenoids or
lergy rather than adenoid obstruc- growth direction of the mandible sim- nasal obstruction in a chronic mouth-
tion, however, the problem may be ilar to that seen in adenoid-obstruct- breather who has a 'long-face" syn-
more difficult to resolve. A recent ab- ed cases. Further, the removal of drome and the nasal resistance is
stract showed that management of al- such enlarged tonsils led to self-im- high, the chronic obstruction should
be removed at as early as five to eight
years of age if possible in the hope
that this procedure will facilitate the
Figure 9 treatment and improve the long-term
Improved Facial Growth Pattern, after Surgical Orthodontics dento-facial stability. If, in the diag-
In a Patient with "Long-Face" Syndrome nosis of such a patient, the nasal re-
sistance is lowered to normal with the
use of a nasal decongestant, the need
for surgically removing the obstruc-
tion becomes less apparent as the na-
sal allergy must be managed. Howev-
er, the objective of treatment is to
restore nasal breathing, and the ENT
specialist or allergist should decide
whether allergic therapy or adenoi-
dectomy is indicated, or possibly
both. Again, if a patient with en-
larged adenoids and chronic mouth-
breathing does not have a "long-
face" syndrome, the need for remov-
ing the obstruction is questionable if
the main reason for removal is to
avoid the potential development of a
"long-face" syndrome.
If the environmental factor is re-
CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 941
solved, some patients with excess low- in this area at present. Many practi- quate oral hygiene.i2 In the absence
er-face height may be treated success- tioners in different areas, such as gen- of this factor, even an excellent occlu-
fully at younger ages by means of or- eral dental practice, physical therapy, sion may break down in an individual
thodontic treatment, while others may cranio-mandibular disorder, gnathol- case. If teeth are moved orthodonti-
require a combination of jaw surgical- ogy, prosthodontics, and oral sur- cally in the presence of active perio-
orthodontic treatment to obtain an gery, offer opposing opinions on Tm dontal inflammation, they may lose
optimal result.48 In still others, the or- diagnosis and treatment. As in any further bone support and attachment,
thodontist may have to attempt ortho- area of medical conflict, however, which may not return after orthodon-
dontic treatment and test the response there is a good body of acceptable in- tic treatment has been completed.5"
to therapy, in order to see if jaw sur- formation in this multivariate area, Adults presenting a malocclusion of-
gery can be avoided. and good diagnosticians and clini- ten have missing teeth as a result of
cians are available to treat the patient caries and subsequent extractions,
Adult Orthodontics, TMJ, with this condition. The orthodontist with severe tipping of the teeth next
Periodontics will treat any shift of the mandible to the extraction sites and extrusion
Much adult orthodontics is being from its proper closure path that will of teeth in the opposing arch. They
done today, with extremely satisfying cause an eccentric or improper posi- may benefit by a combination of or-
results. One difference between tion of the condyles within the gle- thodontic treatment to bring upright
treating the child and treating the noid fossae, and will try to provide a the tipped posterior replacement of
adult obviously has to do with the dental occlusion that is in harmony missing teeth where necessary. One
growth of the face. In the adult there with the muscles and joints.49'50 further difference between orthodon-
is not enough growth potential to Although there is a strong inter-re- tic treatment for adults and for chil-
change the relative size of the two lation between periodontics and or- dren is the duration of retention after
jaws. Therefore, adult malocclusion thodontics, even in children, perio- active orthodontic treatment has
must be diagnosed and treatment dontal examination and treatment been completed. Some adults may re-
planned on the basis of the size differ- planning should be an ongoing and quire a longer period of retention
ence between the two jaws that the vital part of adult orthodontic treat- than children, and some adults will
patient presents, rather than on any ment. Adults contemplating ortho- require permanent lingually bonded
expectation of future growth. Thus, dontic treatment are usually referred anterior retainers in order to avoid
successful treatment of many adult by the orthodontist for periodontal relapse resulting from crowding or
malocclusions may require the extrac- examination. Periodontal disease excess spacing of incisors.53
tion of selected teeth. Had these should be brought under control be-
adults been treated during childhood, fore beginning orthodontic treat- Conclusion
the need for dental extractions might, ment; such treatment will usually in- It is not possible to present more
in some cases, have been avoided be- clude any necessary scaling and root material in a short paper. In conclu-
cause continuing facial growth, as planing. 5 Periodontal surgery prior sion, however, two points should be
well as the greater plasticity of bone to orthodontic treatment is usually made. First, orthodontic treatment
in the growing child, allows certain restricted to isolated pocketing may be beneficial both esthetically
tooth movements to be made more caused by local bony defects and to and to the health of the dentition and
easily. Again, if in the adult the dif- any attached gingival grafts that associated structures. In some cases
ference in size matching between the might be beneficial to the patient dur- the benefits may be more esthetic,
maxilla and the mandible is too great ing orthodontic tooth movement. If while in others the health of the den-
to allow for a good result by means of extensive periodontal surgery is nec- tition may be the dominant factor.
orthodontic treatment alone, a com- essary, it is generally delayed until Secondly, there may be changes in
bination of jaw surgery and ortho- after orthodontic treatment has been the dentition after all orthodontic
dontics is often used to bring about completed, as bony levels and gingi- treatment and orthodontic retention
an excellent occlusion and a more val levels will be changed as a result (passive appliances used for some
pleasing facial appearance. of orthodontic treatment. time following treatment to retain an
Adults often present with temporo- It is most important that an adult orthodontic result) have been discon-
mandibular joint (TMJ) symptoms in whose oral hygiene has been inade- tinued. There are many factors that
conjunction with a malocclusion. quate, and who has therefore re- may be responsible for these post-re-
When Tm symptoms include discom- ceived much periodontal care prior to tention changes, although a direct
fort and pain, it is important to have orthodontic treatment, continue to cause-and-effect relationship has not
the Tm problem thoroughly diag- receive periodontal care on a regular been shown.5456 The most common
nosed and treated prior to or during basis (some periodontists say every occurrence is some degree of crowd-
orthodontic therapy. The orthodon- two to three months) throughout the ing of the lower incisors, which is fair-
tist may be qualified to carry out the course of orthodontic treatment, and ly normal even for orthodontically
TMJ treatment, or may refer the pa- that he or she be motivated to change untreated individuals with good oc-
tient for this phase of treatment while old habits and practise excellent oral clusion and is therefore considered a
trying to eliminate by orthodontic hygiene both during and following physiological change, although it
means any problems in the bite that treatment. does not occur in all cases.5758 Until
may predispose to, or actually cause, It has been shown that the single Behrents completed his recent study,
Tm problems. most important element in the main- the continuing contribution that dif-
There is a great deal of controversy tenance of a healthy dentition is ade- ferential growth in size of adults' jaws
942 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989
might play in this regard was relatively val condition associated with orthodontic orthopedic approach to fixed appliance
unknown.59'60 He showed that the treatment. Angle Orthod 1972; 42:26-34. therapy. Am J Orthod 1972; 61:353-73.
faces of individuals, both male and fe- 13. Zachrisson BU. Cause and preven- 29. Stockli PW, Teuscher UM. Com-
male, continue to grow into their 30s, tion of injuries to teeth and supporting bined activator and headgear orthopedics.
40s, 50s, and even later, and postu- structures during orthodontic treatment. In: Graber TM, Swain BF. Orthodontics,
Am J Orthod 1976; 69:285-300. Current Principles and Techniques. 1985.
lates that this growth may be enough
to cause changes in the dental 14. Zachrisson BU, Alnaes L. Periodon- 30. Demisch A. Effects of activator ther-
tal condition in orthodontically treated apy on the craniofacial skeleton in Class
occlusion.60 and untreated individuals. II. Alveolar II, division 1 malocclusion. Trans Eur Or-
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degree of dental change after reten- 15. Polson Am, Subtelny JD, Meitner term mandibular adaptations to protru-
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larger improvements brought about 1988; 93(1):51-7. Orthop 1987; 92-108.
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very successful and encouraging both der B. Root resorption, marginal bone to activator treatment in Class II maloc-
support and clinical crown length in or- clusions. Am J Orthod 1985; 88:242-51.
to the patients requiring such treat- thodontically treated patients. Acta
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CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989 943
Continued from page 874 source for primary care research con- 45. Lanier B, Trembley N. An approach
* multi-purpose work room where a tinues to be the National Health Re- to the medical management of chronic
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in parallel at work stations or cubi- (NHRDP).12 Recently, a physician with cial Growth. Monograph No. 9. Ann Ar-
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stations can be functioning concur- grants-review process and the admin- 46. Rubin RM. Mode of respiration and
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resources unique to community prac- 49. Roth RH. Functional occlusion for
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A second important principle, RG. Nonextraction orthodontic therapy:
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the project proposal completely once al. Development and management of a ty. Am J Orthod Dentofac Orthop 1987;
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Most departments of family medi- 11. College of Family Physicians of
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1987. niofacial Growth Series, Center for Hu-
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944 CAN. FAM. PHYSICIAN Vol. 35: APRIL 1989