Ortho Flashcards
describe class 2 div 1 incisor and skeletal relationship
inciors - lower incisor edge lies posterior to cingulum plateau of upper incisors, overjet is increased
skeletal - maxilla lies anterior to mandible more than 2mm, class 2
why might treatment be required for class 2 div 1
aesthetics - might be teased at school
increased risk of trauma - 5a, more than 9mm
how can a class 2 div 1 be treated
accept - if low risk of trauma + not bothering pt
growth modification to correct skeletal relationship - upper and lower functional appliance, retrocline uppers, procline lowers, encourage growth of mandible, restrict growth of maxilla
fixed appliance - following functional or accept skeletal and camouflage
URA - not as common now, can tip teeth but wont correct relationship
orthognathic surgery - fixed before and after, if patient no longer growing and movement outwith limits of fixed appliance
describe class 3 incisor and skeletal relationship
incisor - lower incisor edge lies anterior to upper cingulum plateau, overjet may be reduced or reversed
skeletal - mandible lies anterior to maxilla
when would a class 3 be treated
pt affected by aesthetics
dental health affected - gingival stripping or recession
TMD problems
difficulty with function - chewing
what treatment options are available to treat a class 3
accept - if no aesthetic or dental concerns
growth modification - usually not favourable, can get a reverse twin block if young enough
fixed appliance - camouflage skeletal relationship by correcting incisor relationship
URA - can use to expand maxilla or to tip upper teeth infront of lowers
orthognathic surgery - have to have stopped growing, move mandible back, bring maxilla forward, fixed appliance before and after treatment, can take around 3 years
what are causes of an unerupted 21
supernumerary
trauma to deciduous
early loss of primary
retained primary
hypodontia
pathology
what are signs of an unerupted 21
more than 6 months since condralateral erupted
lateral erupted
discolouration to primary
how is a retained 61 treated
2 PA or OPT + Oclussal to locate
referral to paeds and ortho
leave and monitor - possible cyst or resorption
XLA and spontaneous eruption - unlikely if dilacerated, need space maintainer
XLA and chain bonded - difficult if dilacerated
what age should canines be felt for
from age 9
what are clinical signs of impacted canines
pattern of eruption is not symmetrical
discolouration of 2s
sequence of eruption not correct
what are the risks of leaving unerupted canines
cyst formation
resorption of adjacent teeth
resorption of canine crown
ankylosis
how can ectopic canines be treated
unable to align if too close to midline, too high (apical third of lateral), at 55 to midline
surgical removal
surgical exposure and chain
autotransplantation
describe how parallax is used
using two radiographic films to locate an object, radiographs taken at different angels. if object moves in same direction as the tube head - it is palatally placed
how is vertical parallax used
OPT and oblique occlusal - tube head moves up from opt to occlusal, if tooth appears higher up then palatally placed
how is horizontal parallax used
using 2 pa radiographs at different angles - one more to RHS than the other
if object moves to right then palatally
what are benefits of ortho tx
improve aesthetics, improve function, improve dental health
what are the risks of ortho tx
relapse - will need some form of retainer life long, either removable or fixed
decalcification, need to have good patient selection, good OH, weakens enamel, more at risk of caries
root resorption - 1-5% chance but pt has to be aware
gingivitis and gingival recession - poor oh large cause but if thin gingival biotype then recession more likely with movement - increased sensitivity
what should you check when delivering a ura
right appliance for right patient
check prescription is what you asked for
run finger over surface and check for rough areas
check wire for work hardening
insert appliance - check for areas of blaunching
check posterior retention - flyover then arrowhead
check anterior retention
activate appliance
demonstrate removing and inserting
get patient to remove and insert
review in 4-6 weeks
what instructions should be given to a patient when delivering a URA
it will feel big and bulky, will get used to it
will be uncomfortable, means it is working, take pain relief as required
speech will be altered, practice reading aloud
excess salivation - will settle in 24 hours
wear 24 hours a day 7 days a week, including eating and sleeping
remove after meals and clean
remove during contact sports and store in hard container
avoid hard sticky foods - might damage the appliance, and be careful with hot drinks
poor compliance will increase treatment time
emergency contact details
what are the benefits of a base plate
retention, anchorage and connector
what are signs patient has been compliant
patient comes in wearing
patient can speak with appliance in
no excess salivation
signs of wear on the appliance
tooth has moved
active component no longer engaging tooth
what is a flat anterior bite plane and how does it work
fabp is used to reduce overbite - acrylic is oj +3mm to ensure low incisors bite on acrylic
this creates a posterior open bite so molars continue to erupt until come into contact with one another - increasing OVD and reducing OB
space has then been created to reduce the OJ
give the ARAB for reducing OJ + OB
a - roberts retractor 11-22 0.5mm HSSW + 0.5mm ID tubing
r - 16 + 26 adams clasp 0.7mm HSSW
a - moving more than 2 teeth, not good
b - self cure PMMA + FABP (OJ+3mm)
