Removable Appliances Flashcards
Their mechanical properties result in simple tipping movements of teeth, therefore multiple simultaneous tooth movements with apical control are not possible
Removable appliances
Remo app are usually only indicated for specific interventions in the ___ ___ , and the appliance choice in specific cases of ___ __
Mixed dentition
Permanent dentition
Classification of remo app
- active
- mechanical appliances
- functional app
- passive
- retainers
- space maintainers
produce tooth movement and growth modification
Active
carry some active components which are activated to exert active forces
Mechanical app
work by modifying muscle forces and exerting intermaxillary action
Functional app
Examples of active remo
Andersen appliance
frankel appliance
bionator
appliances remain passive in the mouth and they don’t exert active pressure
Passive
Example of passive remo
space maintainers
retainers
What is tipping movements?
are produced when a single force is applied against the crown of the tooth
What is movement of block of teeth?
Influencing the position of the opposite teeth can be achieved by the use of:
flat anterior bite plane: which frees the occlusion of the lower incisor being useful in the overbite reduction
Connected by a baseplate
Indication of remo app
provides a useful means of *extra oral force** to a teeth segment or an entire arch to help achieve Intrusion or distal movement.
Also employed for arch expansion which is another example of their usefulness in moving blocks of teeth.
They are use in a passive role as space maintainers and also as retainers appliances
can be removed for tooth brushing
palatal coverage increases anchorage
easy to adjust
less risk of iatrogenic damage (ex. Root restoration) than with fixed appliances
Useful as a passive retainer.
Useful as a passive space maintainer.
Can be use to transmit forces to blocks teeth
Advantages
Appliance can be left out.
Only tipping movements are possible.
Good techniclan required.
Affects speech.
Intermaxillary traction is not easy.
Lower RA are difficult to tolerate.
Inefficient for multiple tooth of movement
Dis advantages
Four COMPONENTS need to be considered for every RA:
- Retentive components
- active components
- baseplate
- anchorage
These components help to retain the appliance in place and resist displacement.
Retentive components
The effectiveness of the active components depend on …
Retention of the appliance
Good fixation will help patient compliance, ___ and __ __
Anchorage and tooth movement
Two types of retentive components
Labial arch
Clasps
- addams clasp
- c-clasp
- ball and clasp
used for two retention purposes:
as a component of the Hawley retainer
Can also bring a minor overjet reduction
Labial arch
are placed between the maximum circumference of the neck of the tooth and they provide excellent retention should not apply active force and no interference with occlusion
Clasp
3 types of clasp
adams clasp
C-clasp
ball end clasp
Active components (3)
Springs
Simple spring
Compound spring
apply forces to the teeth, so that they can bring the desired tooth movement
Spring
consists of 2 helix of small diameter can be made for 1 or more incisors
The spring is placed perpendicular to the palatal surface of the tooth with a long retentive arm
Z-springs
Z spring indications
to move one or more teeth in the same direction,
ex: the pro-inclination of 2 or more upper incisors for the correction of anterior tooth cross bite
the helix is placed opposite to the direction of the intended tooth movement
it should also be placed along the long axis of the tooth to be moved, perpendicular to the direction of tooth movement
Finger spring
Indications of the finger spring
medio-distal mov of teeth, anterior closure of anterior diastemas
Z pring is a ___ spring
A simple spring
Finger spring is a ___ spring
Compound spring
it forms the major part of removable appliance
it acts as a major connector that connects the other individual components and it also distributes the reaction forces to the anchors areas
Base plate
Two types of base plate
Passive active
Base plate type
when is used as a major connector
Passive
Base plate type
by modifying as an anterior or posterior bite plane
**se pone mayor cantidad de acrílico
Active
Two key factors for a RA success
Patient selection
Appropriate appliance design
Sometimes a removable intra-oral appliance can solve a dental problem in a shorter period of time compared to __ __, and this has also been repeatedly seen in molar distalization.
fixed treatment
From the __ perspective, these appliances can prevent or alleviate crowding of the permanent Incisors.
interceptive
The removable appliances are not considered as alternative method if a patient needs comprehensive orthodontic appliance
No omite que el px No use ortodoncia
appliance design has a key role in success:
- the location and type of clasp (for better retention and no tissue irritation).
- The location of the springs (for maximum range of activation) and their direction (for highest rate of activation).
There are several important points to be considered when using a removable appliance:
> Oral hygiene maintenance is less complicated for patients.
It shortens the fixed orthodontic treatment when it is used in the preliminary stage of the treatment plan.
As an Interceptive method, the appliance may be recommended for those with an increased overjet (protruded upper anterior teeth) in the middle mixed dentition age.
It has a lower relapse rate during the retention period compared to fixed appliances.
In other cases the outcome of the treatment should be maintained with subsequent fixed treatment.
