Management of Unerupted Teeth

Question 1

Reasons for failure to erupt?

Answer 1

OSSA

Mechanical obstruction
Insufficient space
Head and neck syndromes
Genetic and endocrine abnormalities

Question 2

Give 2 examples of mechanical obstruction?

Answer 2

Supernumerary teeth

Cyst/ tumours

Question 3

Why can supernumerary teeth cause failure to erupt?

Answer 3

More teeth = less space = crowding

Question 4

Why can cyst/ tumours cause failure to erupt?

Answer 4

Cystic areas often involves roots/ crowns
Obstruct path of eruption
If become extensive can cause pathological fractures

Question 5

What can cause insufficient space?

Answer 5

Micrognathia

Premature loss of deciduous teeth

Question 6

What is micrognathia?

Answer 6

Jaw too small

Not enough room in arch for teeth to erupt = failure of eruption and premature loss of deciduous teeth

Question 7

Give 2 examples of head and neck syndromes which could cause failure of eruption?

Answer 7

Cleidocranial dysostosis

Pierre-Robin

Question 8

Oral features of cleidocranial dysostosis?

Answer 8

Abnormality of tooth structure/ supernumerary (often multiple)
Hypoplastic maxilla and zygoma
Normal eruption of primary teeth - eruption problem w/ permanent

Question 9

Oral features of Pierre-Robin?

Answer 9

Retrognathic mandible
Crowding/ uneruption
Airway issues

Question 10

Give examples of genetic/ endocrine abnormalities which could cause failure of eruption?

Answer 10

Hypothyroidism

Hypopituitarism

Question 11

How to diagnose failure of eruption?

Answer 11

Majority - cause unknown
Look at area clinically - suspicion e.g eruption dates
Special investigations = radiographs

Question 12

What are the most common teeth to fail to erupt?

Answer 12

8s - insufficient space (mandible curves up towards ramus = reduced space)

8s > max canine > mand 5s > upper incisors

Question 13

What pt’s are often affected by supernumerary teeth?

Answer 13

Cleft pt - 15% of cleft pt will have

Question 14

What is the incidence of midline supernumerary?

Answer 14

1-3%

Question 15

Most common site of supernumerary?

Answer 15

Maxillary midline

Mandibular premolars

Question 16

What problems do unerupted teeth cause?

Answer 16

Resorption - adjacent teeth and internal
Pericoronitis
Denture
Perforation

Question 17

How to diagnose resorption w/ unerupted teeth?

Answer 17

Adjacent teeth - look clinically / radiographs

Internal - can be seen radiograph, often cause extensive damage - hopeless prognosis

Question 18

How can pericoronitis be caused by unerupted teeth?

Answer 18

Cause inflammation around the crown of tooth

Esp if unerupted

Question 19

What unerupted teeth cause the risk of perforation?

Answer 19

Maxillary canines

Perforating into sinus

Question 20

What is the significance of dentures and unerupted teeth?

Answer 20

Eruption under a denture can cause irritation

Question 21

What is the prevalence of unerupted and ectopic maxillary canines?

Answer 21

1.7%

Question 22

Where is unerupted canine likely to be found?

Answer 22

85% cases palatal

Question 23

What radiographs should be used if expect unerupted canine?

Answer 23

Parallax - PA/ anterior occlusal

May want: OPT/ CBCT

Question 24

When to assess for unerupted canine?

Answer 24

11-12 girls
12-13 boys

Always palpate

Question 25

What are tx options for maxillary unerupted canine?

Answer 25

No tx
XLA deciduous canine
Surgical XLA
Surgical exposure 
Surgical transplantation

Question 26

Indications for surgical transplantation?

Answer 26

Last option
Not possible to expose and align orthodontically
Pt doesn’t want prolonged ortho
Failure to align after surgical exposure

Question 27

What must be present at pre-op assessment to allow surgical transplantation?

Answer 27

Sufficient room in arch including vertically

Sufficient alveolar bone