Orthodontic Assessment Flashcards
When should an orthodontic assessment be carried out?
- 9 years old
- brief examination
- 11-12 years
- comprehensive examination
- permanent premolars and canines erupted
- older
- malocclusion may develop in later life
What is the aim of orthodontic assessment?
- determine if a malocclusion is present
- identify the underlying causes
- decide whether treatment is indicated
What is the ideal occlusion?
- rarely found naturally
- Andrews 6 keys
- molar relationship
- distal surface of distobuccal cusp of upper 6
- occlude with medial surface of mesiobuccal of lower 6 - crown angulation
- mesio-distal tip - crown inclination
- no rotations
- no spaces
- flat occlusal plane
- no curve of spee
- molar relationship
What is considered a normal occlusion and malocclusion?
- normal occlusion
- more commonly observed than ideal
- minor deviations
- do not constitute an aesthetic or functional problem
- malocclusions
- more significant deviations from ideal
- may be unsatisfactory aesthetically or functional
- may require treatment, patient influences decision
What does a history for orthodontic assessment include?
- presenting complaint
- how much it bothers the patient
- history of presenting complaint
- past medical history
- past dental history
- social/family history
What conditions contra-indicate orthodontic treatment?
- allergies
- nickel
- more common in those with piercings - latex
- present in elastic bands used
- nickel
- epilepsy
- caution with removable appliances
- drugs
- can cause gingival hyperplasia
- patients requiring MRI
- missile injury possible
What past dental history is relevant for orthodontic assessment?
- frequency of attendance
- must be regular attenders
- nature of previous treatment
- cooperation with treatment
- trauma to permanent dentition
- can result in root resorption
What social/family history is relevant for orthodontic assessment?
- travelling
- distance and time to get to appointment
- transportation
- parents work
- school exams
- habits
- thumb sucking
- proclaimed upper teeth - lower lip sucking
- proclaimed upper teeth - tongue thrusting
- anterior open bite - chewing finger nails
- resorption of upper central incisors
- thumb sucking
What extra oral examination is carried out specifically for orthodontic assessment?
- facial skeletal patterns
- antero-posterior
- visual assessment
- palpation of skeletal base - vertical
- Frankfort mandibular planes angle (FMPA)
- should meet at back of the head - transverse
- asymmetry
- mid-sagittal reference line
- antero-posterior
What could be expected when a high FMPA is measured?
- limited overbite
- anterior open bite
What could be expected when a low FMPA is measured?
- deep bite
What are competent lips?
- lips that meet at rest
- related mentalis muscle
What are incompetent lips?
- lips that do not meet at rest
- relaxed mentalis muscle
What is a lip trap
- upper teeth rest on lower lip
- common with skeletal class II
- can cause procaine of upper incisors
What is a hyperactive lower lip?
- tense, strap like, lower lip
- can retrocline lower incisors
- indicates likely instability at end of treatment
What are the signs of a digit habit?
- proclamation of upper anteriors
- retroclination of lower anteriors
- localised anterior open bite or incomplete open bite
- narrow upper arch
- sucking pulls cheeks in
- molars meet edge to edge
- possible unilateral posterior crossbite
- thumb sucking
- asymmetrical disruption of anterior occlusion
- two digit sucking
- symmetrical disruption of anterior occlusion
At what age can the effects of a sucking habit be naturally reversed?
- 8/9 years
- lips will pull teeth down
What is mandibular displacement?
displacement of the mandible moving from retruded contact position to intercuspal position
What should be checked during intraoral examination of the lower arch?
- degree of crowding
- presence of rotations
- inclination of canines
- angulation of incisors to mandibular plane
What should be checked during intraoral examination of the upper arch?
- degree of crowding
- presence of rotations
- inclination of canines
- angulation of incisors to Frankfort place
- ~110 degrees
What are the different types of incisor relationship?
- class I
- class II div. 1
- class II div. 2
- class III
What is a class I incisor relationship?
lower incisor edges occlude with or lie immediately below the cingulum plateau of the central incisors
What is a class II division 1 incisor relationship
lower incisor edges lie posterior to the cingulum plateau of the upper incisors.
upper incisors are proclined or of average inclination resulting in an increased overjet
What is a class II division 2 incisor relationship?
lower incisor lie posterior to the cingulum plateau of the upper incisors
upper incisors are retroclined and overjet can be minimal or increased
What is a class III incisor relationship?
lower incisor edges lie anterior to the cingulum plateau of the upper incisors resulting in a reduced or reversed overjet
What are the different types of overbite?
- increased, complete and in contact with tooth
- increased, complete and in contact with palate
- increased and incomplete
What is a class I buccal segment relationship?
- upper canine is distal to lower canine
- mesiobuccal cusp of upper 6 lies in buccal groove of lower 6
What is a class II buccal segment relationship?
- upper canine mesial to lower canine
- mesiobuccal cusp of upper 6 lies between lower 5 and 6
What is a class III buccal segment relationship?
- upper canine distal to lower 4
- mesiobuccal cusp of upper 6 lies between 6 and 7
What is a class III buccal segment relationship?
- upper canine distal to lower 4
- mesiobuccal cusp of upper 6 lies between 6 and 7
What special investigations can be carried out for orthodontic assessment?
- radiographs
- OPT
- maxillary anterior occlusal
- lateral cephalogram
- vitality tests
- study models
- photographs
How is orthodontic treatment need assessed?
- IOTN
- index of orthodontic treatment need
