Interceptive orthodontics

Question 1

What 3 problems might you get with an anterior crossbite?

Answer 1

Tooth wear, gingival recession, displacement on closure

Question 2

What are favourable features for correction of anterior crossbite with a URA?

Answer 2

Tooth in crossbite tipped palatally, good overbite (aids stability, prevents it moving back), adequate space to move forward

Question 3

Give 2 ways an anterior crossbite can be managed

Answer 3

URA
2x4 appliance (fixed) - if >1 tooth in crossbite, brackets on incisors and 6s

Question 4

What could cause a posterior crossbite (origin of posterior crossbite)?

Answer 4

Transverse jaw discrepancy (arch width discrepancy or mandibular displacement), mandibular asymmetry, retrusive maxilla sits on wider part of mandible, retrognathic maxilla, after cleft palate surgery?

Question 5

Why need to intercept a posterior crossbite?

Answer 5

• When mandible shifts to one side to achieve intercuspation may lead to grinding and other problems such as TMJ problems, tooth wear and abnormal growth and development of teeth and jaws
  
  • Doesn’t tend to spontaneously correct

Question 6

What 2 things can a deep overbite lead to?

Answer 6

Palatal ulceration, gingival stripping

Question 7

What should you do if have class 2 div 2 with deep overbite?

Answer 7

Give functional first which will sort the overbite and the class 2. If only treat overbite first will then be more difficult treating the class 2

Question 8

What problems can a digit sucking habit cause?

Answer 8

Anterior open bite or reduced OB, proclined upper incisors and retroclined lower incisors, increased overjet, posterior crossbite

Question 9

Aetiology of digit sucking habit

Answer 9

6 or more hours duration, prevention of eruption of incisors, labio-lingual pressure on incisors, lowering of tongue position, unopposed buccinator pressure on UBS’s

Question 10

Which supernumerary is the main cause of failure of eruption of central incisors?

Answer 10

Tuberculate

Question 11

Types of odontome

Answer 11

Compound - discreet denticles

Complex - disorganised mass of dentine, pulp and enamel

Question 12

% of supernumerary teeth in the permanent dentition

Answer 12

2%

Question 13

What % diastemas are due to supernumeraries?

Answer 13

10%

Question 14

Give 3 conditions that have an increased incidence of supernumeraries

Answer 14

CLP, Cleidocranial dysostosis, Gardner’s syndrome

Question 15

Aetiology of midline diastema

Answer 15

Developmental, generalised spacing, hypodontia (missing 2s), midline supernumerary (mesiodens), proclination of upper incisors, low frenal attachment, pathology

Question 16

What is a major cause of impacted 5’s?

Answer 16

Loss of E’s

Question 17

What can an impacted first permanent molar result in?

Answer 17

Pulpitis of E, premature exfoliation of E