Ortho Flashcards
When are orthodontic examinations carried out (3 instances)
What are Andrews 6 keys of ideal occlusion?
4 types of occlusion
- ideal occlusion (unlikely)
- normal level of malocclusion (most common)
- minor deviation
- no aesthetic / functional issue
- malocclusion
- significant deviation from normal
- functional / aesthetic effect
Ortho past medical history: ortho treatment contraindications (4)
Ortho past dental history: important questions (4)
Ortho social history: Habits causing malocclusion and what type of issues these cause?
Age where digit sucking is irreversible
Ortho: What are the 3 facial skeletal aspects of the head? And what does each allow for working out?
Normal angle of vertical one
- anterio-posterior (skeletal class)
- vertical (FMPA)
- transverse (straight on / above asymmetry)
what are the 3 skeletal classes? What causes each? and how would you check this?
Ortho: extra-oral examination: soft tissue checks? (4)
Ortho: 5 stages of extra-oral examination?
- TMJ
- Facial skeletal aspects
- soft tissues
- Skeletal assessment
- compare patient to parent (growth potential / class III occlusion risk)
Ortho: 4 stages of intra-oral examination
- OH and perio health
- Palpate for canines
- Aspects of the teeth (5) - image
- the teeth in occlusion
- incisor, canine and molar relationships
- overbite, openbite/overbite, crossbite, symmetry
Ortho: 2 ways to measure space required and available in crowding?
- mesure total overlap 5-5
- measure arch mesial of 6 to opposite then also incisal edges and do a sum
Ortho: what the the incisor relationship classes
Ortho: Difference between overjet and overbite?
Ortho: canine relationship classes
Ortho: Molar relationship classes
Ortho: What are the 3 stages between examination and treatment?
What type of malocclusion does the early loss of an ‘e’ cause
crowding
What are the 3 main aims for the occlusion following orthodontic treatment?
- stable
- aesthetic
- function
what are the 2 types of aims for ortho treatment? and which treatment is done for each?
URA - only compromise treatment as only tooth tipping
What factors influence an orthodontic treatment plan?
what are the stages of an ortho treatment plan?
what are the 6 treatment options for an ortho treatment plan?
What are the two types of extraction that have to be done in response to another extraction for orthodontic treatment?
What are the 3 grades of crowding in orthodontics? And their treatment
What used to stop posterior drifting and why
3 factors that effect tx plan for orthodontic treatment
Timing
Stability post ortho
Limited movement potential
what are the 4 main aetiologies of malocclusion?
- 3 are local causes
What is the general structure of the jaws in relation to the cranial bases?
Aetiology factors for skeletal causes of malocclusion?
Is class III in ortho hereditary?
it can be, yes
Orthodontic radiographic analysis technique:
Name?
what is the patient positioned in?
what is it for analysing?
name of the analysis done?
what does the analysis do?
Cephalometry / cephalogram
cephalostat
anterio-posterior jaw relationships (skeletal class)
eastman analysis
- angles of jaws in relation to each other and cranial bases and angles of incisors
what are the interventions for ALARP for a cephalogram being taken?
As Low As Reasonably Possible
in cephalometry for orthodontics, what is eastman analysis measuring?
SNP jk
vertical dimension orthodontic view:
what are the two measurements?
how are both of them measured?
Ortho skeletal analysis: transverse view
what can be analysed in this view?
what are the two types of issue there can be here?
What happens in each?
Ortho: what are the main causes of malocclusion caused by the teeth themselves?
No. of teeth
- supernumary
- hypodontia
- retained primary
- early primary loss
- permanent loss
size/shape
- microdontia
- Macrodontia
- abnormal form
positioning
- ectopic
- transposition
what are the 4 types of supernumerary teeth
- Supplemental
- odontome
- conical
- tuberculate
causes of retained primary teeth (5)
- hypodontia
- ectopic / dilacerated primary
- delayed development of primary
- ankylosed deciduous
- pathology
causes of early deciduous tooth loss (4)
- caries
- periapical pathology
- trauma
- root resorption
how much space loss is there when certain teeth are lost
upper vs lower
anteriors/canine/molars
e compared to d
lower has more drift, uppers more tilt
E>D spaceloss
6 steals 5 space
relevant information on the timing of the loss of 6s (age of check and range for age to remove)
and incisors
upper not as much of an issue
lower
- routine assessment of 6s aged 8-9
- as window to extract causing least crowding 8-11
- too early = 5 distal drift
- too late = poor drift of 7s and low closure
incisors
- early = space loss (but want to maintain)
- late = no closure
what are the different types of abnormal form of teeth
peg laterals
dilaceration
accessory cusps/ridges
dens in dente
fused teeth
talon cusps
ectopic teeth:
most common example
- management options (5)
6s
canines due to long path of eruption
- nothing and review
- autotransplantation
- surgical access and ortho
- surgical extraction
- prevention (monitor at certain ages)
6s
- reversible before age of 8
- spacer / extract e
what is the aetiology of soft tissue causes of malocclusion
- digit sucking
- tongue thrust
- labial frenulum (diastama)
how can pathology be a cause of malocclusion
- caries
- cysts
- tumours
Relevance of first 8 weeks of fetus development to facia development
how does the mandible form in the uterus
intramembranous ossification
Bone deposited directly into primitive mesenchymal tissue = Needle like bone spicules form, radiate from primary ossification centres to periphery = joining of bone centres
how does the base of the skull form
endochondral ossification
= Bones form from proceeding hyaline cartilage
definitions in ortho development of the face abnormalities :
- primary and secondary abnormalities
- congenital abnormality
- deformation
- agenesia
- syndrome
facial syndromes from issues in development in first 8 weeks
types of causes (4) and their examples
environmental
- foetal alcohol syndrome
multifactorial
- hemifacial microsomia
- treacher collins syndrome
- cleft lip and palate
syndromes
- crouzon’s
- apert’s
- achondroplasia
genetic
what are the causes and dental implications of cleft lip and palate?
Foetal alcohol syndrome causes and effects
what are the 3 sites of facial growth
methods of facial growth for the:
cranial vault?
cranial base?
maxilla?
mandible?
- surface deposition / resorption on inside and intramembranous ossification at sutures
- surface remodelling and endochondral ossification
- suture growth of mid palatine sutures, frontal bones and zygomatic
- Also surface remodelling of palate (deposition on oral side)
- surface remodelling from condyle (width) and deposition laterally and posteriorly with resorption lingually and anteriorly
Relevance of the pubertal growth spurt in ortho?
difference in timing of maxillary and mandibular growth?
maxilla = slow from 7yrs and only until 12
mand = fast during pubertal period 17/19
Ortho treatment for overcrowding that don’t have to involve extractions? (2)
Ortho treatment for ectopic teeth:
- 6s
- how and treatment
- incisors
- Causes of a abscent incisor (5) and how treat main cause?
ortho treatment for early loss of deciduous teeth:
Compensating or balancing extractions register for each tooth type?
what are the two types of space maintainers in ortho?
when is the extraction of a child’s 6 likely to cause the least issue?
balancing and compensation?
what are the benefits of extracting at this time?
negatives of doing at this time?
5s and 8s present
buccal segment crowding(psoterior crowding)
bifurcation of 7s calcifying
- typically 12-14yrs old
benefits
* reduces chance of malocclusion forming
* 7 will erupt into 6s space
* get a caries free dentition
Ortho treatment for cross bites:
- posterior unilateral
- anterior
- widen upper arch (50% relapse)
- palatal expander with midline screw - posterior bite block and z spring
Ortho treatment when digit habit not stopping? (4)
- what age is this important to be stopped by?
- positive reinforcement
- bitter nail paint
- elastoplast glove
- habit breaker appliance
- URA - single / double goal post
- fixed - tongue rake
Age 9
ortho treatment for a diastema?
- what is the normal size of the gap and what ages have what prevalence
frenectomy little effect on long term prognosis
6yrs old 96%
12yrs old 7% as 3s erupted
2.5mm gap should close
Ortho: infra-occluded primary
- what teeth most common?
- aetiology?
- how diagnose?
- treatment for ectopic and absent?
in which arch is tooth tipping and drifting most likely?
upper = tipping
lower = drifting
ortho treatment: upper permanent canines
- development and prior to eruption
- sign of issue?
- Treatment
- 4 factors required to indicate this and what do after/how long wait - risk if no treatment
What are the limit angles of inclination and retroinclination of upper and lower incisors
issues this may pose
120 degree for anteriors incline
80 degree retroclined lowers
if already at this angle on one arch cant do any more of this movement - if overjet and class I
Ortho: treatment for class ii and class iii skeletal classes
What is the best age for the go to treatment to be done
II
- refrain maxilla growth
- promote mandible growth
- functional appliances (removable twin block)
III
- refrain mandible growth
- promote maxilla
- Bolard implant
- protractor head gear (14hrs/day min to work)
- functional appliance (removable reverse twin block)
need posterior bite plane to diocclude teeth
10-12 yrs old
Very general types of tooth movement? (2)
- physiological (drift / eruption)
- orthodontic (From external force and bone remodelling)
What are the two theories of tooth movement in ortho
what is secondary remodelling
what are the 3 types of orthodontic appliances
For the third type
- how long for
- 3 actions of these (bone and teeth)
- URA
- Fixed
- functional
what are the 6 orthodontic tooth movements?
And the grams of force for each)
Extrusion actually 35 (typo)
what is the histological effects of different amounts of orthodontic force?
possible negative effects of orthodontic force
factors effecting response to orthodontic force
Ortho lab card: what is the aim consisting of?
the aim of THIS specific appliance
ortho lab card: ARAB
What are the 5 displacement forces
Reason for A (second one) and rules for this
B - what other benefits this gives, how made and how far back?
ortho: wires
- what?
- thickness for different uses
- make up?
- HSSW
- Active component (0.5mm), retention (0.7mm)
3.
types of active components
so far…
- z-spring (buccal and slight rotations)
- palatal finger springs + guard
- buccal canine retractions + ID tubing
Ortho: types of retention for URA
Parts of an adams clasp
how to modify
modify fly over THEN arrow heads
ortho: what are the two additions to the base plate you can do in URA
What is the anterior one used for?
ortho: what is the cause of fatigue for HSSW and what does it cause
chromium layer damaged = can corrode
work hardening and breaking = injury / ingestion
i.e. from biting on fly over
Can cause gingival stripping
Ortho: Tool names (3)
Reasons for study models in ortho (7)
What advice do we give the patient post-URA fitting? (8)
How do you know if your patient is wearing their appliance?
Process for fitting an URA (10)
Patient info and instructions
Ortho: advantages and disadvantages of URAs
8 good
4 bad
Ortho: when is an anterior flat bite plane (FABP) used and how do you size it?
what effect does it have?
can it be used in older individuals?
how long worn for
Base plate: FABP : overjet + 3mm
- so teeth cant slip behind bite plane
- creates an anterior openbite as lower teeth move up to occlude with uppers
- no as gingiva and alveolar bone wont grow with tooth in non children
- worn longer than when teeth occlude as soft bone would cause relapse
eruption dates of permanent teeth
Process of tooth eruption (3 stages)
