4. The “ Glossary of Orthodontic Terms ” defines
open bite as a developmental or acquired
malocclusion whereby no vertical overlap
exists between maxillary and mandibular
anterior or posterior teeth. Open-bite must be
considered as a deviation in the vertical
relationship of the maxillary and mandibular
dental arches
INTRODUCTION
5. In an open-bite there should be a
definite lack of contact, in the
vertical direction, between opposing
segments of teeth. The degree of
openness can vary from patient to
patient.
6. 1. Difficulty in speech (dysphonia).
2. TMJ disorders.
3. Functional imbalance.
4. Bad aesthetics.
5. Alteration of incisor guidance.
6. Reduction of normal functional activity.
OPEN BITE CREATES SIGNIFICANT PROBLEMS
SUCH AS
7. 1 . Skeletal Open Bite:
class I
class II
class III
2. dental openbite:
anterior openbite
posterior openbite
CLASSIFICATION
12. DENTO ALVEOLAR OPEN BITE
The extent of the dentoalveolar open bite depends
on the extent of the eruption of the teeth. Eg:
Supraocclusion of the molars and infraocclusion of
the incisors can be primary etiologic factors.
13. In vertical growth patterns the dentoalveolar
symptoms include a protrusion in the upper anterior teeth
with lingual inclination of the lower incisors and over
eruption of posterior teeth and steeper than normal
mandibular plane angle.
14. In horizontal growth patterns, tongue posture and
thrust may cause proclination of both upper and lower
incisors. DrRavikanthLakkakula 12
15. 1.Normal craniofacial pattern.
2.Proclined incisors.
3.Under Erupted anterior teeth.
4.Normal or slightly excessive molar height
. 5.Mesial inclination of posterior dentition
. 6.failure of eruption of teeth with unknown
etiology.
DENTAL OPENBITE IS A OPENBITE WITHOUT FACIAL DISFIGUREMENTS.IT IS
ASSOCIATED WITH SOME OR FOLLOWING CHARACTERISTICS
16. 7.Divergent of upper and lower occlusal planes.
8.No gummy smile.
9.No vertical maxillary excess.
10. Habits like thumb ,finger suking and tongue
thrusting.
11.Without remarkable cephalometric findings.
12.There may be spacing between anteriors.
13. Speech
17. 1. An overjet combined with an open bite of less
than 1mm can be designated as pseudo-open bite
problems.
2. A “ simple open bite ” exists in cases in which
more than 1 mm of space may be observed between
the incisors, but the posterior teeth are in occlusion.
3. A “ complex open bite ” designates those cases in
which the open bite extends from the premolars or
deciduous molars on one side to the corresponding
teeth on the other side.
VARIOUS FORMS OF ANTERIOR OPENBITE:
18. 4. The “ compound or infantile ” open bite is
completely open, including the molars.
5. The “ iatrogenic ” open bite is the
consequence of orthodontic therapy, which
produces atypical configurations because of
appliance manipulation or adaptive
neuromuscular response.
19. It is a condition characterized by lack of
contact between the posteriors when the teeth
are in occlusion. It is mostly occurs in the
segment of posterior teeth. Causes of
posterior openbite :
1.Mechanical interference with eruption
either before or after the tooth emerge the
alveolar bone.
POSTERIOR OPENBITE:
20. 2.Failure of eruptive mechanism of tooth
so that excepted amount of tooth
eruption does not occur.
21. Mechanical interference with eruption may be
caused by ankylosis of the tooth to the alveolarbone,
which can occur spontaneously or as a result of
trauma, or by obstacles in the path of the erupting
tooth. Examples of such obstructions prior to
emergence are supernumerary teeth and non
resorbing deciduous tooth roots or alveolar bone..
22. After the tooth emerges from the bone, pressure form soft tissues
interposed between the teeth (cheek, tongue, finger) can be obstacles to
eruption . Ankylosed teeth are usually in infra occlussion and are said to
be submerged. The most commonly submerged tooth is retained lower
deciduous second molar
23. The second possible cause of eruption failure is a disturbance of the
eruption mechanism itself. These patients have no other recognizable
disorder, and no mechanical interferences with eruption seem to exist. The
condition may be the cause of posterior open-bite which does not respond
to orthodontic treatment.
24. The primary aim of treatment should be to remove
the cause. Lateral tongue spikes are a valuable aid in
control of lateral tongue thrust.Once the habit is
intercepted, a spontaneous improvement often
follows. The posteriors can be forcefully extruded. In
cases of posterior open bite due to infra occlusion of
ankylosed teeth, it is best treated by crowns on
posteriors to restore normal occlusal level.
TREATMENT:
39. E- OROFACIAL MUSCLE ACTIVITY,
OROFACIAL FUNCTIONAL
MATRICES
Schematic
illustrating
balance between
forces of lips and
tongue (arrows),
allowing contact
of maxillary
incisor and
therefore
achieving normal
overbite.
41. Management is based on etiology and localization of
malocclusion
1. Management in dento-alveolar open bite Habit
control and elimination of abnormal perioral muscle
function
2. Management in skeletal open bite
1. During active growth phase. Redirection of
growth.
2. After active growth phase. Extraction and
orthodontics or orthognathic surgery
MANAGEMENT
42. The timing of treatment and determination of growth
pattern are crucial. Based on type of dentition , the
management can be divided into
1 Management in deciduous dentition.
2. Management in mixed dentition.
3.Management in permanent dentition.
43. 1. Control of abnormal habits and elimination of
dysfunction should be given top priority in the
deciduous dentition.
2. The anterior open bite improves as soon as the
habit is stopped.
TREATMENT IN DECIDUOUS
DENTITION
44. 4. Treatment with screening appliances is indicated
in such open- bite cases.
5. A skeletal open bite is seldom observed in the
deciduous dentition. Habit control is of only
secondary consideration in these cases, retarding
the increasing severity of the dysplasia.
6. Extra oral orthopaedic appliances such as chin
cups can be used effectively to redirect the growth.
52. The treatment of open bite remains a
challenge to the clinician, and careful
diagnosis and timely intervention will
improve the success of treating this
malocclusion.
CONCLUSION
