Contemporary orthodontics Flashcards
what are the 3 different types of appliances?
- growth modification - aim to alter growth
- move teeth within existing bony envelope eg. fixed appliances and removable appliances
- retainers
what do we want from appliances ?
we want the best possible outcome
1. appearance
2. function
3. health
what are some other things we want
- comfortable tx
- acceptable appearance during tx
- acceptable tx time
- lowest possible risk during tx
- long term stability
which 2 appliances aim to improve class 2 dental and skeletal relationship?
- functional appliances
- headgear
when is the best time to use class 2 appliances?
11-14 yrs pubertal growth
*can use earlier if bullying or high risk of dental trauma
what are the different types of functional appliances?
- REMOVEABLE
- TWIN BLOCK
- MEDIUM OEPNEING ACTIVATOR
- FIXED
describe removable appliances?
wear for 22hrs a day, remove for eating cleaning and sport
describe twin block appliances
2 pieces that touch together to force pt to bite forward
describe the medium opening activator?
single piece that pt bites into
list all of the different types of removable appliances ?
twin block
medium opening activator
describe the fixed functional appliances
attaches from an upper molar to a lower tooth
piston arms force pt to bite forward
how do all functional appliances work?
by forcing pt to bite forward and that causes muscle to stretch which transmits forces on bones and teeth.
- correct AP relationship and vertical relationship in pts with deep bites
are functional appliances effective?
yes if pt is growing and compliant
what are the dental changes that can happen with functional appliances?
- procline lower incisors
- retrocline upper incisors
- change molar relationship from c2 to c1
what else can functional appliances do to occlusion?
can also correct deep bite
- act as a bite plane to promote molar eruption
list the benefits of functional appliances?
- correct C2 malocclusion =overjet and molar relationship
- can have vertical effects
- small improvement in facial appearance- best if pt has low angle (reduced vertical height) and C2
- can be used with fixed appliances
what are the risks with functional appliances?
- high failure risk of non-compliance
- can impact quality of speech, eating discomfort (due to stretching of muscle), need to take out for sport
what is another appliances which aims to improve C2?
headgear
describe headgears?
- 14hrs per day
- all the time including sleeping except for school and eating and sport
- u can put the force in different directions
- worn for 6-9 months(so as soon as they stop wearing it normal growth will restart)
are headgears effective?
- yes if pt is growing and compliant
what are the dental changes in headgears?
- retract molars from C2 to C1 (may also intrude if there is anterior open bite )
- reduce overjet by retroclining upper incisors
do headgears provide growth change?
- very little evidence of sustained change in growth
how can headgears be used to correct anterior open bite?
can reduce vertical proportions by;
1. intrude maxillary molars
2. restrain maxilla
3. mandible rotates and front teeth close together
what are the benefits of headgears?
- correct C2 malocclusions = overjet and molar relationships
- little change to facial appearance - better than functional appliances if pts have increased vertical proportions
- can be used with fixed appliances
what are the risks of headgears?