Mock SCR Dec 2023 - Ortho Flashcards
Purpose of study models
treatment planning
patient motivators
secondary opnionn
designing a removable appliance
to look at a persons occulsion
Advatantages of a URA
Tipping teeth
excellent anchorage
allows pt to remove and clean to maintain good OH
block movement
overbite reduction
less specailised training
cheaper
shorter chairside time
Disadvatanges of a URA
can easily be removed by the patient
can only move on or two teeth
less precise movement
cannot deal with rotations
Active compontent
what actually moves the tooth
Retention
resistance to displacment forces
speech
gravity
tongue
active component
mastication
Anchorage
the resistance to unwanted tooth movement
Baseplate
self cured PMMA
Connector and retention and anchorage
Removable appliance made of
Stainless steel composed of:
- iron - 72%
- Chromium - 18%
- Nickel - 8%
- Titatnium - 1.7%
- Carbon - 0.3%
Fitting a URA instructions
check the appliance design matches the design speicification for the patient
check the pt details matches the details of the appliance
run finger over the fitting surface to check for sharp edges
check the integrity of the wirework
place in the pts mouth and check for areas of blanching
activate the posterior retention - flyovers then arrowheads
active the anterior retention - flyovers then arrowheads
demo to the pt how to insert and remove the appliance
review the pt every 4-6weeks
activate the component
Patient info and instructions
remove the appliance if taking part in contact sports
the appliance may feel big and bulky to begin with
the patient may expereince excessive salivation
the appliance may impinge on speech
wear the appliance 24/7 including meal times
remove the appliance after every meal and clean with a soft bristle toothbrush
talk to pt about compliance and the requirement to attend appts
avoid hard and sticky foods
provide emergency details
may cause intital discomfort and pain
URA to retract 13 and 23
A - 13 23 palatal finger spring and guard 0.5mm HSSW
R - 16 26 adams clasps 0.7mm hssw and 11,21 southend clasps
A - good as only moving 2 tewth
B - self cured PMMA
URA to retract 13 and 23 and reduce OB
A - 13,23 palatal finger spring and guard 0.5mm HSSW
R - 16,26 adams clasps 0.7mm HSSW and 14 and 24 adams clasp 0.7mm HSSW
A - good as only moving 2 teeth
B - self cured pmma with flat anterior bite plane - OJ + 3mm
URA to correct anterior crossbite
A - z spring - 0.5mm HSSW
R - 16, 26, 14,24 Adams clasp 0.7mm HSSW
A - good as only moving 1 tooth
B - self cued PMMA with a Flat posterior bite plane
URA to retract buccally placed 13 and 23 and reduce OB
A - 13, 23 buccal canine retractor with 0.5mm HSSW and 0.5mm I.D tubing
R - 16, 26 adams clasps and 11,21 southend clasps
A - good as only moving 2 teeth
B - self cued PMMA - flat anterior bite plane - OJ + 3mm
URA to reduce OJ 21,22,11,21 and OB
A - roberts retractor 0.5mm HSSW and 0.5mm I.D tubing
R - 16,26 adams clasps and mesial stops on 13 and 23
A - good as short rooted teeth
B - self cured PMMA - flat anteiror bite plane - OJ +3mm
Expanding upper arch
A - midline palatal screw
R - 16, 26, 14,24 Adams Clasp 0.7mm HSSW
A - good as reciprocoal anchorage
B - self cured PMMA with a Flat posterioer bite plane
Class 2 div 1
when the lower incisors lie posterior to the cingulum plaeteu of the upper incisors
the upper incisors are proclined or of average value
the oj is increased
there is a narrow upper arch
digit or thumb sucking habit present lips incompteent with lip trap present
Accept, growth mod, camofloufage, orthognathic surgery if completed growth
Class 2 div 2
when the lower incisor edge lies behind to the cingulum plaeteu of the upper incisors
the upper incors are retroclined
oj is minimal or increased
upper laterals the cingulum can be reduced
the upper 2’s have mesiolabially rotation present and proclined
high lower lip line <FMPA and LAFH, lip trap
Accept, growth mod to get to class 2div 1, camoflauge, orthognathic surgery
Class 3
when the lower incisors lie anterior to the cinglum plaeatu of the upper incisors
the upper incisors are procline and lowers are retroclined
the oj is reversed
can casues tmj issues, ging recession, asymmetry, speech probs, asethetics
How to assess the anterior posterior position
have the frankfort plane horizontal to the floor and palpate the skeletal bases
by the use of a lateral ceph
Purpose of URA
habit breaker
expand the upper arch
anchroage
tipping teeth
space maintaner
reduce overbite
Andrews 6 keys
class 1 molar and incisor relationships
tight approximal contacts with no contacts or rtoations
from the canines posterior slight lingual inclination
flat occlusal plane or slight curve of spee
long axis of tooth with mesial inclination
Types of anchorage
simple
compound
reciprocal
absolute
conical (quadhelix, palatal arch with nance button, transpalatal arch)
Function of quadhelix
bilateral expansion
habit breaker
for cleft lip and palate
fan expansion
aymmetrical expansion
rotation of molars
Relapse most prone in
AOB
crowding
rotations
midline diastema
ectopic canines
OJ
the horizontal distance between the labial surface of the upper incisors and the labial surface of the lower incisors
OB
the vertical overlap between the upper and ower teeth - usually 50% 1/3rd
Crossbite
when the lower arch lie outside the position of the upper teeth
the buccal cusp of the lower teeth lie more buccally than the buccal cusp of the upper teeth
Anterior open bite
no vertical overlap present between the upper and lower incisor teeth
Causes of AOB
endogenous tongue thrust
low labial frenum
digit or thumb sucking
supernumuerary present
class 3 malocclusion
cerbral palsy
Assess the vertical pattern
by the upper anterior face height:lower anterior face height (glabella:subnasale - subnasale:menton)
by the FMPA - the frankfort - porion to orbitale and the mandibular - the gonion to menton
Assess the transverse position
TMJ and symmtery checked
Soft tissues
lips - competent/incompetent
lip trap present
TMJ
asyymetry
nasioloabial angle
tooth showing
lip trap present
Intra oral look for
eruption of teeth
OH
Perio
Centrelines
Incisor relationship
Molar relationship
missing teeth
crowding present
supernumerary teeth
AOB
OJ
OB
upper incisoros - proclined etc
rotation
crossbites present
Retained primary teeth causes
absent successor
ectopic tooth/canine
dilacerated succesor
infraocclued primary tooth
Most common infraocculuded tooth
in the manidble and the lower D
mandble>maxilla
Tx for an infraoccluded tooth
if absent premanent then can maintain or xla with band and loop on 6’s and can have distal stiops on 4’s
if present permanenet then can xla when contacts go subging or when root formation complete on the the permanent tooth
When is the best time to carry out an XLA of a molar tooth?
at calcification of bifurcation of the 2nd molar starting to calcify
usually around 8.5-9.5 years
What is the incidiences of missing upper lateral incisors?
2%
What is the most common missing tooth type
lower 3rd molars
lower premolars
upper laterals
What are the indications for a lateral ceph
to aid diagnosis
treatment planning
progress monitoring
When is a CBCT carried out
for cleft lip and palate ts
orthognathic cases
impacted teeth and resoprtion/ adj to each other
view of sturcture anomalie
Tests for infra occluded teeth
palpation
mobility
sound/percussion
radiographs
Casues of impacted 1st molars
eruption cysts
long path of insertion
crowding
small maxilla
What do you check with impacted 1st molars
check mobiiligy of E’s
can cause pulpitis of E’s or premature exfoliation of E’s
Anterior cross bite
palpate canines at 9years
Issues with anterior cross bite
ging recession
tooth erosion
speech and aesthetics
displacement on closure
mobiligy lower incisors
How to manage an anterior cross bite
URA with a zpring or Tspring if premolar/molar
Causes of an anterior open bite
presence of supernumarary
digit sucking
low frenum
delayed eruption
underlying skeletal discrepancy
disabilities - cerebral palsy
tongue thrust
What measurement do you carry out orthgnathic surgery for an anterior open bite?
> 4mm
Ectopica canines intra oral
palpate buccal and palatal to see if can feel the permanenet successor
check mobility and colour of primary canine
positin of lateral incisors
mobility of lateral incisors
What investigations to carry out for an ectopic canine
OPT and anterior maxilla occlusal
or
2PA’s
CBCT
Causes of an ectopic canine
long path of eruption
genetic link
crowding
ectopic position of tooth germ
Tx for an ectopic canine
if you leave the canine it risks root resoprtion of lateral incisors, resorption of canine crown
ankylosis of erupted canine
loss of primary canine
Surgical - when the canine is not deemed alignable - this can be when the canine is too high in the apical 1/3rd of incisor root
too close to midline or>55 degress to midsggital plane
Removable appliance to correct overbite
autotransplantation when the malpostion of the tooth is too muc for orth alignment
no anklyosis present on canine
if the patient requires quicker tx
Risks of ortho
relapse
soft tissue trauma
decalcification
root resoprtion
loss of perio support
toothwear
allergy
loss of vitiality
ulceration
headgear truama
Types of retention
Hawley retainer
thermoplastic retainer
fixed retatiner
Advantages and dis of fixed retainer
Adv - compliance, anesthetics, non invasive, done chairside and cheap
Dis - poor OH, does not incorporate all teeth, etching damages the teeth, 50% fail
Adv and dis of hawley
Adv - removable so OH good, incoporates all teeth, strong, allows occusal setting, minor tooth movement
Dis - removable so pt complaince, speech issues, aesthetis, expensive and time consuming to make, invasive on tongue
Adv and dis of thermoplastic
Adv - aesthetics, less invasive, all teeth, OH good, cheaper, easier to make
Dis - non resilant, does not allow occlusal setting, complaicne, easily lost, distorted with heat
Supernumary teeth common in
anterior region and males more than females,
gardener syndrome
children with cleft lip
celdocredial dysplasia
Functional applaince indications
average or reduced FMPA
uncrowded arches
lower incisors upright or retroclined
mild to mod class 3
How does a functional applaince work?
enhancment of mandibular growth by movement of the mandibular condyle out of fossa, promoting growth of the condylar cartilage, and forward migration of the glenoid fossa
What does the AP position measure?
The overjet
What does the vertical position obtain
overbite - if behind the occipiut then a reduced FMPA
Transverse position
for centre lines and occlusion
what to look for in an I/O exam for ortho
caries
perio
OH
Missing teeth
dentition type
