Functional appliances Flashcards
Define functional applainces
loose, usually removeable IO devices which alter the muscle forces against the teeth
How do functional appliances work?
alter neuro-muscular action to affect bony growth and occlusal development
posture mandibles forwards in growing patients
which dentition are functional appliances normally used and why
mixed
to treat paediatric malocclusions
In which techniques are functional appliances used?
Growth modification
Growth guidance
Functional growth guidance
Functional appliance therapy
define growth modification
taking advantage of a childs growing years to guide proper jawbone formation using ortho applainces
can correct existing maloccusions or prevent them from occuring
In which types of malocclusion would functional appliances be used?
Class II
Class III
name 8 indications for a functional appliance
good dental health motivated pt pre-adolescent growth phase mild or moderate skeletal discrepancy Increased OB/OJ proclined maxillary central incisors well aligned arches co-incident centre lines
name contraindications for functional appliances
poor motivation >14 year poor dental health condylar disease unfavourable facial growth
Give an example of unfavourable facial growth which don’t respond to functional appliances
increased vertical facial proportions
especially anterior open bite
Give 4 advantages of functional appliances
removable- good for dental health
avoid extractions- if good response to treatment
reduces incidence of trauma
accelerates skeletal growth
give 5 disadvantages of functional appliances
bulky affects speech need pt compliance lack of detailed tooth movements ST trauma
what are the 2 types of functional appliances and where is the energy stored in each type
fixed- energy stored in appliance
removable - energy stored in muscles and ligaments
Where are the forces applied to in the 2 types of functional appliances?
ST, teeth and bone
Name 6 types of removable functional appliances
flat anterior bite plane bionator activator twin block fraenkel teuscher
name 3 types of fixed functional appliances
herbst
jasper jumper
twin block
how does a flat anterior bite plane work?
removeable
has no posterior occlusion, allowing posterior teeth to continue to erupt to open a deep bite
what does a flat anterior bite plane treat
a deep over bite
describe the twin block appliance
most popular
well tolerated by pts
made up of 2 parts- upper and lower fit together using posterior bite blocks with interlocking bite planes–>which posture the mandible forwards
describe a bionator appliance
removeable
less bulky than an activator
corrects overbite and overjet by promoting lower jaw growth
describe the activator applaince
move mandible forwards to correct class II change dental relationships in all 3 planes of space
describe he frankel appliance
removeable
has buccal shields to hold away the cheeks
postures mandible forwards
describe the herbst appliance
fixed
less bulkier than twin block
postures mandible forewards
eliminates pts OB
describe the jasper jumper applaince
fixed
advances the maxilla
class II and class III
what kind of records would you take ?
photos
lateral ceph
study models
why should a function occlusal record be taken when taking impressions?
to describe the exact position of the mandible in all 3 dimensions
What should be adjusted
clasps so they fit and are retentive
how long should functional appliances be work
24 hours- only removed for cleaning, sport, musical instrument
what should you measure at review appointments
OJ
How is the success outcome measured>
OJ- reduced to 2mm
What is partial success?
OJ is 50% less than measurement at beginning
which study investigated the success of functional appliances and what were the results
Cohen
1/3 success
1/3 some progress
1/3 no change
can functional appliance be used in permanent dentition?
unlikely- end up having orthognathic surgery
why is age 10 the best timing for functional appliance
growth potention
degree of parental control
E space
what is the E space/leeway space
5 permanent successor is smaller than the E so when the 5 erupts the extra space is called the leeway space
