7 - Adult orthodontics Flashcards
Who is the typical patient seeking adult orthodontics?
- under 40s
- female
- previous tooth loss
Why do adults seek orthodontic treatment?
- improve dental appearance if refused treatment as child or was not available
- relapse
- adjunctive treatment for restorative, reduce periodontal drift or alongside orthognathic surgery
Why is consent essential in adults with heavily restored dentition?
- higher risk of tooth loss
- higher risk of fracture or tooth breakdown
Why is correcting transverse discrepancies more difficult in adults?
- midpalatal suture is interdigitated
- can only expand maxillary base with surgery
- it is possible to tip teeth to some extent
How do adults differ in their orthodontic treatment from children?
- lack of growth
- periodontal disease
- missing or heavily restored teeth
- physiological factors
- adult motivation
How does growth affect adult orthodontics?
- are non-growing
- growth modification is not possible, so must accept skeletal discrepancy or surgery
- overbite correction is more difficult
- altering arch width is more difficult
Why is overbite correction more difficult in adults?
- bone is more developed and less favourable to extrusion of molars which is usually achieved with FABP
- usually opt to intrude upper incisors
How does anchorage change with LOA?
Loss of anchorage value to each tooth so teeth may move quicker
How do the periodontal tissues impact adult orthodontics?
- periodontal disease is more common and loss of attachment
- previous LOA does not preclude orthodontics, but active disease does
- treatment planning surrounding centre of rotation and anchorage is important
How does the centre of rotation change with LOA?
Centre of rotation moves apically as the bony fulcrum of the tooth has reduced
How do missing teeth or restored teeth impact adult orthodontics?
- tooth loss can cause remaining teeth to drift or tilt
- restorative materials can complicate bonding of brackets to teeth
- RCT must be well obturated and symptomless
How do physiological factors impact adult orthodontics?
- decreased cell turnover so initial movement can be slower (especially when closing extraction spaces)
- lighter forces are required
How does motivation impact adult orthodontics?
- usually well motivated, as internal motivation rather than third party in children
- usually sought referral themselves
- may request more aesthetic appliances
How can orthodontics be used as an adjunct to restorative treatment?
- upright abutments to aid retention of bridgework, dentures or implants
- intrusion of over erupted teeth
- extrusion of teeth to increase crown length
How can orthodontics be used as an adjunct to periodontal treatment?
- correction of migration, proclined incisors and increased overbite
- perio must be stabilised prior to ortho treatment
- required lifelong retention
Why do teeth migrate after periodontal disease?
Loss of transeptal fibres
What is important to include in the consent form for a perio patient undergoing orthodontics?
Dark triangles between teeth due to LOA
How can orthodontics be used as an adjunct to orthognathic treatment?
- pre-, peri- and post-surgical orthodontics
- align and coordinate arches
- decompensate incisors
What does it mean to decompensate incisors?
Correct the angulation of the incisors
What are Andrews six keys?
- tight approximal contacts with no rotations
- class I incisors
- class I molars
- flat occlusal plane or slight curve of Spee
- long axis of teeth have slight mesial inclination (except lower incisors)
- crowns of canines-molars have lingual inclination
Why can you not place ceramic brackets on the lower teeth?
- ceramic is harder than enamel
- if the upper incisors occlude against the ceramic, they may chip
How are lingual appliances applied?
As an indirect restoration in one piece
Give examples of short term orthodontics.
- inman aligners
- six month smile
