Ortho Assessment Flashcards
Why do we do an ortho assessment?
- To determine if any malocclusion is present
- Identify any underlying causes
- Decide if tx is indicated
What causes asymmetry issues to occur?
Issues with growth of condyles
What age do ortho assessments occur?
- Brief exam at 9 years
2. Comprehensive exam when premolars and canines erupt (11-12yrs)
What do we look for in an ideal occlusion? (6)
- Molar relationship
- Distal side of upper molar occluding with mesial side of lower molar - Crown angulation
- Crown inclination
- No rotations
- No spaces
- Flat occlusal planes
PMH:
List some conditions that are now a contra-indication to orthodontic tx (3)
- Allergy
- Epilepsy
- Drugs
- Certain drugs lead to gingival inflammation
- Could be difficult cleansing or cleaning brackets
Questions to ask in PDH
- Frequency of attendance
- Nature of previous tx
- Co-operation w previous tx
- Trauma to perm dentition
What are some habits that can influence ortho issues?
- Thumb sucking
- Procline uppers - Lower lip sucking
- Procline uppers - Tongue thrust
- OJ - Chewing finger nails
- Root resorption
What are the steps of an ortho assessment (5)
Hx Examination - look at skeletal bases SI Diagnosis TX
Extra-oral exam
- Skeletal base
- Soft tissues
Lips:
Competent / incompetent
Tongue:
Position, habitual + swallowing
Habits:
Thumb sucking
Speech:
Lisping - TMJ
What 3 planes should a facial skeletal pattern be considered in?
- Antero-posterior
- Vertical
- Transverse
What are the 2 ways to carry out an AP skeletal assessment? (2)
- Visual assessment
- Skeletal assessment vertical + lateral (asymmetry) - Palpate skeletal bases
How do we carry out a vertical assessment?
Involves the Frankfort - Mandibular planes angle (FMPA)
2 lines should meet at the back of the head
How does a reduced FMPA angle present?
2 lines don’t meet at the back of the head
How does an increased FMPA angle present?
2 lines meet well before the back of the head
Define incompetent lips
Lips that don’t meet at rest
What can a lip trap cause?
Proclined upper incisors
May lead to relapse of OJ if persists at the end of tx
What can a hyperactive low lip cause?
Retroclined lower incisors
What is a tongue thrust associated with?
AOB
Some people push their tongue forward when they swallow (ant tongue thrust)
2 types:
Adaptive
- we can close the AOB
Endogenous
-tx will relapse
What does digit sucking cause? (4)
- Proclined upper incisors
- Retroclined lower incisors
- Localised AOB or incomplete OB
- Narrower upper arch +- unilateral posterior Xbite
What do we check the TMJ for as part of the extra-oral exam?
- Path of closure
- Range of movement
- Pain
- Click from joint
- Deviation on opening
- Muscle tenderness
What is mandibular displacement?
Displacement of the mandibule up and to the right from RCP to ICP
What to check as part of intra-oral exam (7)
- OHI + Perio health
- Count teeth from back
- Teeth of poor prognosis
- Assess crowding/spacing/rotations
- Inclination/angulation
- Palpate for canines if not erupted
- Note teeth of abnormal shape/size
What are the 3 main risks of ortho tx?
- Decalcification
- Root resorption
- Relapse
Course of action for mesially tipped canine?
Extract 4 and canine will just tip back
How do we assess the angulation of incisors to the mandibular plane?
- Pull down the lower lip
- Assess the angle the lower incisors make to your finger
What should the angulation of incisors to the frankfort plane be?
110 degrees
Where does the FF measure from?
Top of the ear to bottom of the orbit
What do we look for when studying teeth in occlusion (7)
- Incisor relationship (BSI)
- OJ
- OB/ open bite
- Molar relationship (angles classification)
- Canine relationship
- Cross bites
- Centre lines
What are the incisor relationship classifications? (4)
- Class I
- Class II (Div 1 +2)
- Class III
- OJ,OB + Centrelines
Class I incisor relationship
Normal OJ + OB
Class II div 1 incisor relationship
Increased OJ, front teeth beyond lowers
Class II div 2 incisor relationship
Centrals retroclined
Class III incisor relationship
Anterior positioning of mandible to maxilla
What teeth do we measure for an OJ?
Any of the 4 incisors
Canine relationship classification (3)
Class I
- Upper canine distal to lower
Class II
- Upper canine anterior to lower
Class III
- Upper canine posterior to lower
Function of lateral ceph
Measurement on angles and distances between points of the skull
Ortho checklist for basis of referral letter (7)
- Name/age/sex of patient
- H/CO
- Incisor relationship
- Skeletal base (AP, V, T) - Teeth present/absent
- OH
- Poor prognosis - Lower + upper arch
- OJ
- OB
- Centrelines
- Molar relationship
- Xbites - IOTN score
