ORTHODONTICS; A guide to the perplexed
Contents
History of
What
causes orthodontic problems?
Why
carry out orthodontic treatment?
What
does an orthodontist do?
How do
braces work?
My teeth
are straight, now what?
Who
should carry out orthodontic treatment?
Tags: orthodontic;orthodontic problems; orthodontic treatment;orthodontist; braces ;My teeth are straight; orthodontic treatment;
ORTHODONTICS: from the Greek- orthos- right,
correct + odous odont- tooth.
The diagnosis and
treatment of malpositions of the teeth.
History of orthodontic problems
Whilst the
possibility of moving children's teeth by applying light pressures was known to
the Romans, it was only in the mid-19th Century that Orthodontics started to
take shape as a science based branch of Dentistry. The early writings of
American and European dentists in the 1800’s described the use of various
appliances for the straightening of teeth and even jaws, and some of these
inventions are still in use today, albeit in a more sophisticated form.
What causes orthodontic problems?
Heredity
Whilst the exact
mechanisms are uncertain, there can be no doubt that many of the elements that
make up dento-facial structures are influenced by heredity. Children, after
all, tend to look like their parents, who commonly try to identify family
features in their offspring - "…he's got his mother's nose, his father's
chin, grandpa's eyes and grandma's teeth". As a result of this genetic
mixing it will often occur that the parts don't fully match. The
teeth, inherited from one parent, may not be the appropriate size to fit into
the jaws, inherited from the other parent. This may lead to crowding and malposition
of the teeth if they are relatively too large for the jaws or spacing if the
teeth are too small.
Clefts of the lip
and/or palate, which have a strong hereditary background, will have obvious
effects on the teeth and jaws.
Abnormalities
of biting and chewing; swallowing; speech and mouth-breathing as opposed
to nose-breathing, may all contribute to the development of orthodontic
problems.
Sucking habits in
childhood, in particular fingers or pacifiers, are often blamed for the
protrusion of the upper front teeth. However, there is no firm evidence that
such habits are, indeed, a major cause of orthodontic problems. Many children
with sucking habits who stop at an early age can then develop
a normal bite in the absence of other factors. It would seem that
the longer the duration of the habit and the greater the intensity
and pressure applied during sucking, the greater the likelihood of causing
of an orthodontic problem.
Many orthodontic
patients thrust their tongue forward, particularly during swallowing and
speech. These tongue thrusts have a marked impact on the position of the front
teeth as the tongue is a large muscle and the continuous pressure on the teeth,
mainly during swallowing, will move the teeth, usually forwards.
Dental disease
Early loss of baby teeth due to dental decay may cause
unwanted movements of surrounding teeth and may complicate a pre-existing
orthodontic problem or cause such a problem where none existed. In such a case
it is important to seek advice on the need for a space maintainer to prevent
such movements. Similarly, the loss of permanent teeth due to decay
or gum disease may turn a non-treatment situation into a treatment case.
Ongoing dental care, both at home on a daily basis and at the dentist and
hygienist on a regular basis, is essential, to ensure a healthy
mouth.
Dental anomalies
Congenital absence
of teeth is not uncommon. Third molars or wisdom teeth, which only start to
erupt at 18 years or more, are the most commonly absent teeth with upper side
incisors, lower second bicuspids and lower incisors next. In fact any
permanent tooth may be congenitally missing with consequent problems of
excess space, although in an otherwise crowded mouth a missing tooth or two may
be an advantage!
Extra teeth
sometimes develop and they will tend to cause crowding.
Sometimes the shape
or size of the teeth may be abnormal, either on a full mouth basis as part of a
general condition, or affecting only a few teeth.
Developmental position of orthodontic problems
Teeth may develop
in an abnormal position and then fail to erupt properly. This mainly affects
upper cuspids (canines) which may end up trapped in the palate and require
complex treatment to bring them into their correct position.
Trauma
Trauma to teeth
and/or jaws is regrettably common, particularly in boys in their boisterous
teens. Jaw fractures can lead to disorganization of the occlusion (bite) and
damage to the growth centres of the lower jaw which are situated in the joints
in front of the ears. Trauma to teeth may result in their loss with consequent
movement of the adjacent teeth.
Why carry out orthodontic treatment?
There are basically
3 reasons for carrying out orthodontic treatment and in any individual
patient any or all may apply.
The usual complaint
voiced by patients and their parents on their first visit to the
orthodontist is that they "don't like the way the teeth and/or jaws
look" At the same time, there are those patients
who are not at all bothered by the appearance of their teeth but are
brought to the orthodontist solely as a result of parental concerns. Given the
motivation and cooperation demanded from the patient to carry out
successful orthodontic treatment, it is important for the orthodontist to listen
to the patient as well as to the parent. Unlike most other dental treatments
which are of short-term duration, orthodontic treatment typically is carried
out over a period of several years and depends as much on the patient’s
cooperation as on the orthodontist’s skill. An unwilling patient will not,
generally, achieve a successful result
Function
Usually associated
with more severe jaw discrepancies in which there is a lack of full contact
between the teeth, either front or back, resulting in a reduced ability to bite
and chew. However every orthodontist will have seen patients with such
malocclusions and yet able to bite and chew without trouble, which demonstrates
the remarkable adaptability of the chewing mechanism.
Health
Intuitively, one
might think that very crowded teeth are more prone to dental and gum disease
due to the difficulty in cleaning to the required standard because
of overlapping teeth which trap food. However this has not been shown to
be true in the majority of cases - provided that the patient is
given proper instruction on the use of a toothbrush, dental floss and a good
mouthwash and is motivated to carry out a thorough mouth cleaning each morning
and evening.
When is the right time to start orthodontic treatment?
Once again there
are differing views on the appropriate timing of orthodontic
treatment. Some authorities suggest starting early, at 8-9 years,
while others suggest waiting until all the baby teeth have changed over to
permanent teeth, which is usually 11-14 years. There are many and varied
considerations as to the correct timing for each individual child, but it is
probably best to seek the advice of an orthodontist at the age of 8-9. If it
turns out to be too soon, one can always wait.
What does an orthodontist do?
At the first visit
to an orthodontist, the patient’s personal details are recorded and a
comprehensive medical and dental history is taken. Emphasis is placed on
finding out what the patient, adult or child, is hoping to achieve from the
treatment. A clinical examination of the face and mouth follows and
additional examinations will be requested. These may include: various X-rays,
both of the teeth and of the jaws; CT scans, particularly to locate unerupted
teeth; plaster models to allow measurements of tooth and jaw size to be made.
Occasionally further consultation with other dental or medical specialists will
be needed in order to obtain a comprehensive picture of treatment needs.
Diagnosis
With all the
relevant information to hand, the orthodontist can now make a diagnosis and fit
a particular patient into the appropriate place on the spectrum of known
orthodontic conditions.
Treatment planning of orthodontic problems
Having determined
where the teeth and jaws are before treatment, it is now necessary to decide
where they should, ideally, be after treatment. The journey between these two
positions is the treatment. Research has indicated that there are certain
relationships between teeth and jaws which are more aesthetic and more stable
than others and it is towards these relationships that treatment is planned.
However one must take into account that there are differences between ethnic
groups in the norms of these relationships.
Treatment
Some treatments
need to change the relationship between the upper and lower jaws in order to
establish a normal base for the straightening of the teeth. In a young, growing
child this may be achieved by the use of various appliances which exert
pressure on one or both jaws to try to modify and influence the direction and/or
amount of jaw growth. This is more correctly called Dento-facial Orthopaedics.
In an adult, significant changes in the jaws will usually require surgery.
Once the jaw
relationship is corrected, the teeth can be straightened. The first
consideration is the availability of sufficient space to achieve the planned
correction. Space can be obtained in a number of ways: widening of the
jaws, particularly the upper; expanding the dental arch in a forward or
backward direction, or both; narrowing teeth by removing a very thin layer of
enamel so that each tooth requires less space in the arch and; finally, by
removing permanent teeth. Determining which method of space gaining is
appropriate for each case is a product of the amount of space
needed, where in the mouth it is needed, the state of health of the teeth and,
to a large extent, the treatment philosophy used by the orthodontist. The
argument over the removal of permanent teeth in orthodontic treatment has been
going on for 100 years or more, with some saying "never" and others
saying "almost always". As with such arguments the truth lies
somewhere in the middle and each case must be considered on its own
merits.
The range of
orthodontic appliances now available is diverse. The usual fixed metal braces
come in numerous shapes and sizes, each product having its supporters. If
the results are good, it does not really matter if one uses brand X or brand
Y. For adults who are reluctant to show too much metal, there are now
fixed white braces, made of plastic or porcelain, as well as clear plastic
plates, computer designed and manufactured to carry out tooth alignment, which
can be removed. The ultimate in invisible orthodontic treatment is now the
lingual brace which is fixed on the inner surface of the teeth; this brace
combines the advantages of fixed appliances with invisibility.
Additions to fixed
appliances may be necessary for full correction of certain orthodontic
problems. These may include: headgears with neckstraps or headcaps or, on rare
occasions, both; removable plates, upper or lower,or both; chincups or face
masks.
A new addition to
the orthodontist’s toolbox is the temporary implant. These are small titanium
screws that are screwed into the jaw bone, under local anaesthesia, acting as
anchor points for tooth movement. Their use may often eliminate the need for
external headgears. Unlike the implants used to replace missing teeth, these
orthodontic implants are not locked into the jaw bone and can easily and
painlessly be removed when no longer needed.
The use of elastic
bands in orthodontic treatment has a history going back over 100 years. They
are a convenient way to apply the light pressures needed to move teeth and are
easy to hook on to the braces as directed by the orthodontist.
The pressures
applied to the teeth by orthodontic appliances of any type are transmitted to
the roots of the teeth and there they cause changes in the tissues that
separate the roots from the jaw bone. These tissue changes cause a process of
bone shrinkage on one side of the root and bone building on the other side,
thus the tooth moves along with its surrounding bone. This process is caused by
cells; cells need a blood supply and therefore it is light forces
that move teeth quickest. Heavy forces will damage the cells and the blood
vessels and slow down the whole process.
Does the treatment hurt?
Fixing the braces
to the teeth does not, generally, hurt although some pressure may be felt when
the bands are pushed onto the teeth. As a reaction to the light orthodontic
pressures teeth often become sensitive for a day or two but this wears off and
can be controlled by an occasional pain killer, if needed. Removable plates are
usually made with a plastic base which restricts the space for the tongue and
may interfere with speech. Again this wears off after a day or two. Similar
speech interference occurs after fitting lingual appliances. Research has shown
that 95% of patients with lingual appliances can speak normally within 2 weeks of
the brackets being fitted.
My teeth are straight, now what?
The completion of
orthodontic treatment to the satisfaction of patient, parents and orthodontist,
is often the start of the most difficult phase of the treatment process. On
removing the braces, the teeth are very unstable and can very quickly move away
from their ideal position. Therefore retainers are needed to hold the teeth in
their post-treatment position. These may be removable plates or wires fixed
behind the teeth. The use of the retainers according to the orthodontist’s
instructions is an essential part of the treatment and must not be neglected.
Even with fulltime retention over a period of years, changes are often noted.
During the first year after the completion of treatment these changes can be
considered to be reactions to the treatment. Beyond this, most changes are due
to the normal process of growth and maturation which would have caused such
movements even in the absence of orthodontic treatment. Perfect and permanent
stability is rarely, if ever, achievable.
Who should carry out orthodontic treatment?
In most countries
any licensed dentist is entitled to carry out any dental treatment, including
orthodontics. However, given the complexity of diagnosis and treatment planning
of orthodontic cases and the range of treatment options which are now
available, it is advisable to turn to a properly trained and qualified
orthodontist. Formal courses to train orthodontists are available at many
Universities throughout the world and may take as long as 3-4 years. At the end
of the course, students face stringest examinations that test their theoretical
and practical knowledge. Those who pass these examinations are entitled to call
themselves "Specialist". Some countries or states have specialist
registers in all branches of Dentistry and these can usually be viewed at local
or national health authority offices or websites. It is worth
checking into qualifications before choosing an orthodontist although
personal recommendations from satisfied former patients are also a valuable
guide.
At the end of the
treatment, the reward for all that hard work and perseverance on the part of
the patient and the orthodontist will be an attractive smile, balanced facial
features and the good feeling that comes with a job well done.
A short glossary of orthodontic terms, or
“How to understand what
the orthodontist is telling you”
Dental arch or
arcade: The row of
teeth on each jaw, upper and lower.
Dentition: All the teeth in the mouth. The deciduous dentition
is all baby teeth, 20 in number, themixed dentition is some baby
and some permanent and the permanent dentition is all
permanent teeth, 32 in all, including the wisdom teeth.
Incisors: The front teeth, 2 on each side, one central and
one lateral. Used for cutting food therefore have sharp edges.
Cuspids
(canines): Also known as
“eye-teeth”, pointed teeth similar to the sharp fangs of meat-eating animals
such as the dog and the cat families.
Bicuspids
(premolars): 2 in
each quarter, used for grinding food before swallowing together with the
molars.
Molars: 3 in each quarter, these are the only permanent
teeth which do not replace a baby tooth. They come into the mouth at 6 years,
12 years and 18 years, approximately.
Maxilla: The upper jaw.
Mandible: The lower jaw.
Tempero-mandibular Joint
(TMJ):
The joint which
connects the mandible to the skull on each side and on which the mandible
pivots during chewing. The TMJ can be felt just in front of the ear when the
mouth is opened and closed. The growth centres of the
lower jaw are located in the joint.
Orthodontic
bands:
Stainless
steel rings which are fitted to the teeth, usually the back molars, and to
which wires and other accessories are attached.
Orthodontic brackets:
Small attachments,
metal, porcelain or plastic which are glued directly to the teeth or attached
to metal bands.
Bands and brackets
are the means by which light forces are applied to the teeth using wires,
springs and elastics
Headgears:
Wires which
are attached to bands within the mouth and which have a second wire outside the
mouth to which a neckstrap or headcap is attached to pull on the teeth.
Functional appliance
: A removable or
fixed appliance which uses the force of the muscles to apply pressure to the
teeth and/or jaws in order to modify the direction and/or amount of growth.
These are most effective in younger patients during their growth spurt, ages
9-14.
