S2 - Clear Aligner Flashcards
What can cause huge issues if failed to recognise
- class IIIs
- skeletal discrepancies
- growth patterns
- deep bite
- bite jump corrections
- need to recognise when you are off track and need a way to get tx back on track
Principles of orthodontic treatment (5)
- Records: Hx, I/O photos and scans, radiographs
- Diagnosis: summary & problem list
- Aims of Treatment: how you know when you are done
- Treatment Options: including no tx and informed consent
- Treatment: including review & retention
What are clear aligners
3D printed - direct or thermoformed on a model
Made from clear plastic
Proactive approach (rather than reactive)
Envisage where you want the teeth to go - need space for tooth to move and need force to apply to the tooth
Advantages vs Disadvantages of clear aligners
- aesthetic
- removable
- comfortable
- compromised/missing teeth
- protection against parafunction (bruxism)
- easy to pause tx (e.g. traumatised central incisors)
- removable therefore rely on compliance (24h/day w 2hrs off to eat)
- some movements are difficult
Differences between aligners and braces
How to manage possible problems which may arise with aligners
- If tx lags/offtracks (space between tooth and aligner): what is the main aim, rescan or continue
- Lost aligners: keep old sets can skip ahead or go back to last one
- Poor compliance: can always put braces on…
i.e. problems can be solved
Principles of orthodontics
force applied → areas of compression and tension on PDL, osteoclasts cause bone resorption on compression side, osteoblasts lay down bone on tension side → tooth moves
How do teeth move with braces vs aligners
Braces - wires engages w bracket to create a couple - push & pull (bracket/wire interface)
Aligners - can only push teeth - you need space for the tooth to move into and a surface to push on: aligner/tooth and/or aligner/attachment interface
Why do you need attachments?
some movements require an additional surface to push on
e.g. in image, to extrude tooth theres nothing to push on, attachment provides this
Why do you generally need attachments for posterior rotations but not anterior?
anteriors have flat surfaces to push on whereas posteriors are round therefore nothing to push on, need attachments to rotate
What dictates attachment requirement?
type of tooth movements - tipping, bodily, extrusion, intrusion, rotation, torque, support
Why are attachments needed for bodily tooth movement
force applied away from COR creates a moment (rotation)
attachments will create the necessary force system to prevent tipping
Why are attachments needed for expansion?
bodily movement, otherwise will just tip out
Are attachments needed for intrusion and extrusion?
intrusion - need attachments on supporting teeth
extrusions - need attachment on extruding tooth
What is important to plan with regards to bone
teeth need to stay in bone! otherwise leads to recession or tooth loss
easy to miss where bone is on digital scan
may need exos or IPR to gain space
Why aligners make class IIIs and deep bite worse but help class IIs and AOBs?
thickness of aligner material → intrusive force on posteriors, rotates md forward
Why is diagnosis, problem list and aims so important?
- identify problems
- what you can and cant do
- pt needs to understand limitations, can you meet their expectations → refer if need
- define what the planned outcome is, thats how you measure success
What is needed for good clinical records
- pt assessment & evaluation
- I/O (mandatory nowadays)
- I/O photos (including incisal edges & gingival margins - track chips and recession) → take photos are every single appt
- E/O photos
- 3D face scans & dynamic records (videos)
- radiographic: OPG and lat ceph at least, CBCT
Why are I/O scans useful
- to track movement
- use as part o diagnostic process - multiple setups, IPR vs exo (dont do IPR on growing pts unless rly needed)
- treatment stimulation - for pt education
What can treatment monitoring do to increase efficiency**? and provide **better patient experience?
- evaluate fit of aligners
- reduce unnecessary in-office appts
- adapt to patient’s biological response
- anticipate upcoming appointments
- improve pt compliance (as know someones watching)
- better engage, communicate and educate the patients
- more convenient for pt
- provide constant feedback and updates on tx
What is pt management moving towards now/in the future
hybrid model
How do you decide change rate of aligners
remote monitoring helps match pt’s compliance and biology
might depend on age
assess what is a good fitting aligner
check tracking - if not tracking well might lengthen scan interval and shorten if tracking well
What is digital orthodontics
use of technology to: collect information, analyse potential teeth or jaw problems
use digital software to: formulate tx plan, manufacture appliance, execute treatment
monitor process virtually/digitally
