Adult Orthodontics

Question 1

Why do adult want orthodontic tx? (3)

Answer 1

• Improve dental appearance
  – Refused treatment as a child
  – Lack of earlier opportunity
  – Unhappy with result of earlier treatment: Relapse or Poor initial treatment
• Some may have functional complaints from severe malocclusions (less common)
• Adjunct to other dental treatment
  – Facilitate restorative treatment
  – After periodontal drift
  – Part of surgical correction of jaw discrepancy

Question 2

List factors specific to an adult dentition that would affect orthodontic tx. (5)

Answer 2

1. Lack of growth/small amounts of growth (mostly in vertical direction)
2. Periodontal disease
3. Missing/heavily restored teeth
4. Physiological factors
   Decreased cell turnover, initial movement can be slower
   = Use lighter forces to avoid undermining resorption
5. Adult motivation = very well motivated

Question 3

How does little/no growth affect ortho tx in adults? (3)

Answer 3

Growth mods not possible = accept skeletal discrepancy and align or camouflage the discrepancy or have surgery

Difficult to correct overbite = tooth intrusion required

Mid palatal suture closed = can only expand maxilla with surgery or by tipping the teeth (limited capabilities)

Question 4

What are the implications of orthodontic tx in patients with active perio? (2)

Answer 4

the loss of support can;
- Lead to centre of rotation moving apically
- lead to reduced anchorage (as teeth provide less resistance)

Question 5

Describe the ways in which orthodontic tx can be used as an adjunct to restorative tx. (3)

Answer 5

Making abutment teeth Upright - aid restorations such as bridges, implants and dentures.

Intrusion of over-erupted teeth - achieve a desirable crown margin

Extrusion - increase crown length

Question 6

Describe the ways in which orthodontic tx can be used as an adjunct to periodontal tx. (4)

Answer 6

can be used to correct/reduce the consequences of perio disease (once disease stabilised and inactive);

corrects;
* tooth migration
* Proclined incisors
* Spacing
* increased overbite

Question 7

List Andrew’s 6 keys.

what is the difference between younger and older patients in relation to the ideal treatment outcome (Andrew’s 6 keys)?

Answer 7

1. Tight approximal contacts with no rotations.
2. Class I incisors.
3. Class I molars.
4. Flat occlusal plane or slight curve of Spee.
5. Long axis of the teeth have a slight mesial inclination except the lower incisors.
6. The crowns of the canines back to the molars have a lingual inclination.

In adult patients, often compromise is required as it it very difficult to achieve all 6 keys in an adult dentition (easier to achieve in adolescent px)
– figure out what the main complaint(s) is and gauge the px’s attitude towards the final result.
e.g. correct the complaints and compromise the rest

Question 8

What appliances can be used to tackle adults aesthetic concerns? (3)

Answer 8

ceramic brakcets

lingual appliances

removable aligners e.g. invisalign

Question 9

What are the disadvantages of ceramic brackets? (4)

Answer 9

• Easily broken (especially during debonding)
• Higher friction (sliding the tooth along the wire is harder)
• Slower tooth movements
• Can cause wear and grooving of the incisal edges (as harder than the enamel)