Interceptive Ortho I Flashcards
What are interceptive orthodontics
any procedure that will reduce or eliminate the severity of a developing malocclusion
What is the mouth like at birth
gum pads
the upper gum pads are rounded while the lower is U shaped
they often appear very class II
sometimes have anterior open bite
What is the eruption of deciduous teeth
6 months - 2.5 hours
ABDCE
lowers before uppers
What is the deciduous dentition like
incisors more upright
spaced
more susceptible to wear
What is the impact of deciduous dentition spacing on crowding
if there is no spacing = 2/3 develop crowding
<3mm = 50% crowding
3-6mm = 20% crowding
> 6mm = no crowding
What teeth are early mixed dentition
6s, 1s, 2s
Which teeth are late mixed dentition
4s, 3s, 5s, 7s
How can lower labial segment crowding spontaneously improve
up to 3.5mm of crowding may spontaneously improve
transverse growth increasing inter canine width
Why do diasetemas in 6 YO improve
due to the canine
if its <2.5mm the diastema should lose
What could be the cause of an unerupted central incisor
supernumeraries
trauma/dilaceration
other pathology
How do we deal with supernumerary if they are delaying eruption
remove deciduous and supernumerary
expose/bond
create space
monitor
What can trauma to permanent deciduous predecessor result in
can result in dilaceration
What is the aetiology of median diastema
normal (small teeth)
supernumerary
missing teeth
radiograph
What is the leeway space
difference between EDC and 345
What is the normal lee way space
- 5mm in maxilla
2. 5mm in mandible
When measuring spaced required for premolars and canines what do we measure
measure from medial of 6 to distal of 2
want more than 18.5mm for there to be room for permanent successor
What is balancing
take out on contralateral side
How does the effect of balancing and compensating vary with
crowding
age
arch
What is compensating
take out from opposite arch
What is the management for early loss of As and Bs
little impact
don’t balance or compensate
What is management for early loss of C’s
balance
midline will shift
worse if severely crowded
What is the management of early loss of D’s
small CL shift
balance under GA
What is the management of early loss of the Es
not to balance
major space loss
upper > lower
When should the first assessment of premolars be
9 years
What are general rules for extraction of 6s
if extracting lower take upper
don’t balance with sound tooth
if extracting upper don’t necessarily take lower
When extracting first molars what do you want ideally
7s furcation forming 8s present class 1 av/reduced OB moderate lower crowding mild moderate upper crowding
What is the appliance for a posterior unilateral cross bite
active component - midline screw adams clasps on 4s and 6s has posterior bite planes overcorrect can take 6-9 months to correct
When do we treat anterior cross bite
early
treat early when laterals come through with URAs
What is the stability of anterior cross bite
if you have a good overbite for ACB then don’t need a retainer even if patient grows
What is the stability of posterior cross bite
50% relapse
overcorrect to maintain corrected even after relapse
What are malocclusions that come from habits
proclined upper incisors
retroclined lower incisors
asymmetric AOB or reduced OB
unilateral posterior x bite
When do you want the patient to give up their habit
<10 years as can resolve
What do we do for retained deciduous teeth
take out relatively soon as there is capacity for adult teeth to drift
What are infra occluded deciduous teeth called
submerging teeth due to ankylosis happens more often in lower doesn't always have sucessor happens in 10%
How can we diagnose infra occluded deciduous teeth
visual
percussion - tap it
radiographs
What is the management for submerging teeth
if has a permanent successor then observe for one year
if no successor then extract it
When should you extract the submerging tooth
when only 1mm of crown showing
Where do the upper canines develop
palatally below the orbit long migration migrate and lie labial and distal to root apex of upper laterals 90% palpable by 11 yrs if can't feel ti then radiograph
How do we assess canines for delayed eruption / ectopic position
assess position of upper canines from 10 yrs onwards
should palpate by 11 years
mobile C’s, symmetry
What is ideal radiographs for localisation of ectopic canines
anterior maxillary occlusal
OPT
If you detect an ectopic canine then what can you do
extract the Cs
success depends on how high the canine is and how much of the adjacent incisor it overlaps
if doesn’t overlap by over a half then over 90% chance
if more than half then 60%
if lots of space then higher success rate, can get rapid maxillary expansion and high pull head gear
What is the cause of reverse overjet
dental/skeletal/combination
What is the incisor angulations that we need to treat a reverse overjet using camouflage treatment
Upper has to be less than 120 and lowers less than 80 degrees
What are the functional appliances for class II
functional regulator (FR) frankel III
What is the difference between FR2 and FR3
FR3 is an FR2 but upside down
What is the function of FR3
tries to change soft tissue environment to make sure teeth can move in desired direction
What are the components of the functional appliances of FR2 and 3
buccal shields
pelots
tight lower labial bow
spring to proline ULS
What is the function of the buccal shields
tries to hold the cheeks and buccinator away from teeth to allow them to expand naturally
What is the function of the pelots
at the front
hold lips away from teeth to allow them to tip forward
What is the function of the labial bow
tip teeth back
What is the success rate of the functional appliances for class III
<30%
What is maxillary protection
pull maxilla forward
What does maxillary protraction consist of
reverse pull headgear with facemask
can be with rapid maxillary expansion
What is the success rate of maxillary protraction
70% success rate
What is the newer technique for maxillary protraction
strong class III elastic traction worn FT
applied to bone screws or plates fixed to maxilla and mandible
applied to bone screws or plates fixed to maxilla and mandible
90% success rate
What is the cause of increased OJ
dental skeletal combo
What is the issue of an increased OJ
risk of trauma
incompetent lips
What is the interceptive tx for class II
functional appliance
head gear to restrict maxillary forward growth
How does the functional appliance for class II work
harness the forces generated by big muscles that sit around the jaw to promote mandibular growth and restrict maxillary growth and top teeth back
