Transcript PREVENTION IN ORTHODONTICS

PREVENTION IN
ORTHODONTICS
PREVENTION IN ORTHODONTICS
•
In all medical branches the great attention is
directed to prevention and prophylaxy. However in
orthodontics the situation is slightly different.
• The considerable variability in dentofacial
development seen in child populations is the result
of tissue adaptations to complex interactions of
a great number of aetiological factors. The causes
of malocclusion may be classified in many ways,
but two major groups of aetiological factors may be
distinguished:
1. genetic factors
2. non – genetic ( enviromental ) factors
PREVENTION IN ORTHODONTICS
• It is commonly accepted that the etiology of any
problem should be contained in the diagnosis.
• As regards malocclusion, it is a developmental
problem, not a pathologic one, and although we
can say that both hereditary and enviromental
factors are important influences on development,
often we are not able to ascertain which
malocclusions are determined largely on
a genetic basis, which result largely from
enviromental factors, and which are
combination of hereditary and enviromental
factors
PREVENTION IN ORTHODONTICS
• The majority of patients are not easily placed in
one of these categories, because a single clearly
identificable agent is not apparent.
• It is recognized now that multifactorial causes
must be considered and sometimes the
development of maocclusions may be the result of
factors which are not recognizable with our present
knowledge.
• Therefore the prevention in orthodontic is very
difficult and limited.
PREVENTION IN ORTHODONTICS
• Prevention in orthodontics means such
arrangements contributing to
favourable development of the face,
jaws, teeth and establishment of
normal dentofacial relations.
• It involves both prenatal and postnatal
stages of development
PRENATAL PREVENTION
• It consist of general arrangements providing for
healthy development of the foetus.
• Mother should be protected from chemicals,
radiation, infections and other agents capable
of damaging the embryo. These factors if given
at a critical time may cause severe dentofacial
defects, among which the cleft lip and palate is
the most common orthodontic problem.
Improper diet, faulty position of the foetus in
utero or birth injury could also adversely affect
the postnatal development
POSTNATAL PREVENTION
• The majority of
enviromenat causes of
malocclusion are those
appearing after birth.
• Dental caries is an
important cause of
localized malocclusion.
Interproximal caries which
decreases the mesiodistal
widths of deciduous molars
may result in a forward
drifting of the first
permanent molars and
shortening of the dental
arch
POSTNATAL PREVENTION
POSTNATAL PREVENTION
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More extreme carious lesions may necessitate
early extraction of deciduous teeth.
This often result in pronounced migration of
adjacent teeth into the extraction space and
substantial loss of space for the permanent
teeth. The degree and type of migration is
related to:
the type of deciduous tooth extracted
the patient´s age when deciduous tooth or
teeth are lost
the relative space in the dental arch
the quality of intercuspation of the molar
teeth
POSTNATAL PREVENTION
• With regard to the type of
the tooth, it has been
found that extraction of
the second deciduous
molar result in loss of
space in the posterior
part of the dental arch
due to a mesial
migration and
inclination of the first
permanent molar. This
is more accentuated in
the maxilla than in
mandible
POSTNATAL PREVENTION
• When a deciduous first
molar or canine is lost
prematurely, there is also
tendency for the space to
close.
In this case, however,
space closure seems to
occur primarily through
distal drift of the permanent
incisors.
This result not only in
a tendency to crowding,
but also to an asymmetry
in the occlusion due to
a drift of the midline to the
side of tooth loss.
POSTNATAL PREVENTION
POSTNATAL PREVENTION
• As regards the age factor, it has been shown
that premature loss of deciduous molars after
the age of 8 years only affects dental arch
space to a minor degree.
• If the dental arch is spaced the effects of early
loss are minor, whereas if there is crowding
space loss may be severe
POSTNATAL PREVENTION
•
Prevention should involve general prevention of the dental
caries:
1. Dental hygiene training should start right after eruption of
the teeth.
2. Right nutrition, fluoridation are also of great importance.
3. Where possible, carious deciduous molars, second molars
in particular, should be adequately restored.
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Where one first deciduous molar or deciduous canine is
lost, the simplest treatment is to balance this by
extraction of the corresponding tooth on the opposite
side of that arch. This will prevent a shift of midline which
is often one of the greatest long term problems following
early loss of such a tooth. Balancing extraction for the loss
of second deciduous molar is not usually indicated.
POSTNATAL PREVENTION
• The premature loss of
deciduous molars
immediately leads to
consideration of space
maintenance.
• Using space maintainers is
dependent on a thorough
diagnosis, and it may be
modified with subsequent
treatment planning.
• Space maintainers may be
removable or fixed.
POSTNATAL PREVENTION
There are number of problems associated with the use of
space maintainers:
• the danger of increased food stagnation and
• lack of patient cooperation,
so they should be fitted only in selected cases where they
will be of positive benefit to the patient.
Their use should be confined to the good, dentaly aware
patient who has lost one or perhaps two deciduous
molars and where it is felt that orthodontic treatment
might be avoided or considerably simplified by the
prevention of space loss.
POSTNATAL PREVENTION
Thus space maintainers are not indicated for:
• the patient with spacing – where space loss will not occur
anyway, or
• with moderate crowding – when extraction of permanent
teeth and orthodontic treatment will be needed.
Where it is estimated that there is
• just sufficient room for all permanent teeth or
• in severely crowded case, where the extraction of the one
permanent tooth from each quadrant will provide just
enough space
space maintainers may offer definite advantages.
POSTNATAL PREVENTION
POSTNATAL PREVENTION
• Prolonged retention of
deciduous teeth can delay
the eruption of its permanent
successor or deviate the
permanent successor from its
normal course of eruption.
Deflection of the permanent
teeth is most commonly seen
in the anterior region, where
it may cause permanent
incisors to erupt labially or
lingually of the dental arch. In
order to prevent it, the
deciduous tooth should be
extracted as soon as
possible.
POSTNATAL PREVENTION
POSTNATAL PREVENTION
• Habits:
A light force applied to teeth over a prolonged period of
time will change their position and alter the configuration
of the alveolar process.
Such forces produced by thumb, finger or dummy
sucking, lip biting, nail biting, and other habits and
pressures, can displaced teeth in an unfavourable way
and create malocclusion.
The severity of malocclusion is determined by the duration,
frequency, and intensity of the habit and partly by the
individual developmental pattern.
POSTNATAL PREVENTION
• Dummy sucking and thumb
sucking are very common in the
infant but no attempt should be
made to control them at this stage.
• Important is the shape of the
dummy. Long dummy is not suitable.
In order to prevent further
irregularities short dummy or
dummy of special shape called
NUK is preferable. This shape of
the dummy beter imitate the
conditions during the breast feeding.
Using the dummy through day is
normal in that age.
• Should the habit persist into the
period of deciduous dentition,
a malocclusion may result
POSTNATAL PREVENTION
• The sucking habit may involve other fingers, or the
fingers may be placed in many different ways. All these
variations produce their own characteristic form of dental
irregularity.
• Dummy sucking is less harmfull than thumb sucking
as it rarely persist at the age of six when permanent
incisor erupt. While thumb sucking usualy persist
longer ( till the age of permanent dentition ), the
pressure is greater so it may cause severe open bite.
Therefore very early stop of using of a dummy is not
recomended, because of risk that young and imatured
child substitutes the dummy by more harmfull thumb.
POSTNATAL PREVENTION
The typical malocclusion seen in cases of thumb
sucking is
• anterior open bite
• proclination of the upper incisors
• a lengthening of the maxillary dental arch
• anterior displacement of the maxilla and
• lateral crossbite.
• This habit may also obstruct the normal anterior
development of lower dental arch relative to the
upper, which result in distocclusion.
POSTNATAL PREVENTION
POSTNATAL PREVENTION
• The anterior open bite produced by a sucking habit may
initiate habitual thrusting of the tongue into the space
between the upper and lower teeth.
• Even if the sucking habit is terminated the unfavourable
posture of the tongue may persist in these patients and
preserve the vertical malocclusion.
• As an adaptation to an existing malocclusion abnormal
swallowing ( sometimes incorrectly refered to as infantile
swallowing ) may develop. The presence of a large overjet
and open bite force tongue to place between separated
anterior teeth in order to perform a deglutition without food
and liquids escaping from the mouth.
POSTNATAL PREVENTION
POSTNATAL PREVENTION
In these cases the active orthodontic treatment
is indicated to correct the open bite. Correction
of the malocclusion is usually followed by
a normalisation of the swallowing pattern.
POSTNATAL PREVENTION
•
Early termination of the sucking habit means that
normal dentofacial growth without interference from
dummy or thumb is re-established long befor eruption of
premolars and canines and open bite correct itself
spontaneously.
• If the child over 7 years of age persists in thumb sucking
an attempt should be made to stop the habit.
• As a first step, encouragement should be tried and is
often successful.
• Should this fail, and provided that the child is keen to
stop, a simple removable appliance is often sufficient
to break the habit
POSTNATAL PREVENTION
Oral screen is a thin shield of
acrylic which lies in the
buccal sulcus. In its active
form it contacts only the
upper incisor and contribute
to correction of their
proclination.
Also other kinds of
removable appliances can
be used.
There must be no coercion
but the presence of the
appliance makes the habit
less satisfying.
POSTNATAL PREVENTION