ORTHODONTIC APPLIANCES Flashcards
(38 cards)
what are removable appliances
are ortho appliances (braces) which are NOT attached to the teeth and can be removed for cleaning and sporting activities.
what are the uses of removable appliances
- conventional removable appliances
- removable functional appliances
-removable retainers (essix etc) - aligner treatment eg invisalign
what are the 4 components of a conventional removable appliance
- 4 KEY COMPONENTS (BARA)
B - baseplate
A - active components
R - retentive components
A - anchorage
what are some ACTIVE COMPONENTS within a conventional removable appliance
- springs
- screws
- bows
what determines the force produced by a component (ie springs, screws, bows…)
- length of wire
- radius (diameter) of wire
- elastic modulus (stiffness) of wire
what are the RETENTIVE COMPONENTS of conventional removable appliances
- southend clasps
- adams clasps
- delta clasps
- ball ended clasps
what is the baseplate of a conventional removable appliance?
- made of acrylic
- holds the components together
- can incorporate bite planes (posterior and anterior)
- provides anchorage for the appliance
What is ANCHORAGE
This is the resistance to unwanted tooth movement
what information should be provide when designing a removable appliance
- drawing of appliance
- retentive components
- active components
list some advantages of a removable appliance (patient perspectives)
- can REMOVE for cleaning
- can REMOVE for sport/wind instruments
list some advantages of a removable appliance (orthodontic perspective)
- good anchorage
- can move blocks of teeth
- cheap
- less chairside time than fixed appliances
- easy to adjust
list some limitations for removable appliances (patient perspectives)
- dependant on pt cooperation
- temp effect on speech/eating
- lower removable appliance not well tolerated
list some limitations for removable appliances (ortho perspective)
- limited ortho movement (no bodily tooth movement - tipping only)
- retention post correction can be difficult
- requires good technical support
what is the equipment required for fitting a removable appliance
- adams pliers
- spring forming pliers
- measuring devide
-acrylic trimmer - screw key
what do we do at a first review after pt has been sent away with there removable appliance
- see approx 4 weeks after fit
- any speech problems?
- ask if patient has experienced any problems with appliance
- check appliance for signs of wear
- check soft tissues for ulceration/indentations
- review OH
- record progress of tooth movemements
- FURTHER REVIEWS ON A 4-6 WEEK BASIS
What are removable appliances most commonly used for?
Anterior cross bites (interceptive orthodontics)
what are FUNCTIONAL appliances
these are orthodontic appliances (braces) which alter the MUSCLE forces against the teeth and craniofacial skeleton.
list 3 key terms we use for fucntional appliances
- growth modification
- growth guidance therapy
- functional appliance therapy.
what is important to note about functional appliances?
- they do not grow the mandible !
- 70% of change will be DENTO-ALVEOLAR!
what factors would make someone suitable for a functional appliance? (6)
- class 2 (commonly used)
- class 3 (rarely used)
- mild or moderate skeletal discrepancy
- need to have good dental health
- motivated pt
- GROWING PATIENT (pre-adolescent growth phase)
why wouldnt we provide someone with a functional appliance ? (5)
- condylar disease
- unfavourable facial growth
- severe class 2 skeletal
- poor motivation
- non-growing patient
what is the most common removable appliance in the UK
- twinblock appliance
what are the advantages of a twin block (5)
- removable design means that it is good for dental health
- may avoid xlas if good response to treatment
- may accelerate growth
- may reduce incidence of trauma
- may reduce complexity of treatment
what are the disadvantages of a twin block (5)
- removable are bulky appliance - pt may not comply
- fixed (herbst) - have repeated fractures
- can affect speech
- can cause soft tissue trauma
- lack of detailed tooth movements
