Dental Anomalies

Question 1

What dental anomaly results in fewer than normal teeth being present?

Answer 1

Hypodontia

Question 2

What tooth is most commonly affected by hypodontia?

Answer 2

third molars

Question 3

What teeth are least likely to be missing in hypodontia cases?

Answer 3

• first permanent molars
• upper central incisors

Question 4

What syndromes are associated with hypodontia?

Answer 4

• ectodermal displasia
• down syndrome
• cleft palate
• Hurler’s syndrome
• incontinentia pigmentii

Question 5

What restorative problem is common when upper lateral incisors are missing due to hypodontia?

Answer 5

Over-eruption of lower canines

Question 6

What treament options are available for patients with hypodontia?

Answer 6

• removable prosthesis
• orthodontics
• composite build-ups
• porcelain veneers
• crowns & bridges

Question 7

Why is preventative treatment so important in patients with hypodontia?

Answer 7

Patients already have a reduced dentition so you dont want to risk them losing anymore teeth

Question 8

What problems are associated with hypodontia?

Answer 8

• abnormal shape & abnormal form of teeth
• spacing
• submergence
• deep overbite
• reduced LFH

Question 9

Who is hyperdontia more common in?

Answer 9

males > females (2:1)

Question 10

what is Hyperdontia?

Answer 10

Additional teeth to the normal dentition

Question 11

In which jaw are hyperdontia teeth more commonly found?

Answer 11

Maxilla

Question 12

What are the different types of supernumerary teeth?

Answer 12

• conical
• tuberculate
• supplemental
• odontome

Question 13

How do conical supernumerary teeth present?

Answer 13

cone shaped

Question 14

How do tuberculate supernumerary teeth present?

Answer 14

barrel shaped, has tubercles

Question 15

How do supplemental supernumerary teeth present?

Answer 15

looks like tooth of normal series

Question 16

How do odontome supernumerary teeth present?

Answer 16

irregular mass of dental hard tissue, compound or complex

Question 17

What is the most common cause of delayed eruption of permanent incisor teeth?

Answer 17

Supernumerary teeth

Question 18

what are microdont teeth?

Answer 18

teeth that are smaller than normal

Question 19

give an example of microdont teeth?

Answer 19

peg-shaped lateral incisors

Question 20

what is macrodontia?

Answer 20

when teeth are larger than normal

Question 21

what is germination?

Answer 21

one tooth splits into 2

Question 22

What is fusion of teeth?

Answer 22

2 teeth join to form 1

Question 23

What is taurodontism?

Answer 23

flame shaped pulps in teeth

Question 24

What is dens in dente?

Answer 24

“teeth inside teeth”
- extra growths on teeth that have their own pulp systems
- very hard to treat if they become decayed

Question 25

What different enamel anomalies exist?

Answer 25

- amelogenesis imperfecta - environmental enamel hypoplasia - localised enamel hypoplasia

Question 26

what are the different forms of amelogenesis imperfecta?

Answer 26

- hypoplastic - hypocalcified - hypomaturational - mixed forms

Question 27

what are some environmental causes of enamel hypoplasia?

Answer 27

- systemic - nutritional - metabolic - infections

Question 28

what are causes of localised enamel hypoplasia?

Answer 28

- trauma - infection of primary predecessor

Question 29

what systemic disease can cause MIH ?

Answer 29

liver or kidney failure during tooth development

Question 30

What is the aetiology of amelogenesis imperfecta?

Answer 30

Familial inheritance - autosomal dominant, recessive & x-linked

Question 31

How is amelogenesis imperfecta diagnosed?

Answer 31

- check family history - AI generally affects both dentitions - affects all teeth - look at tooth size, structure & colour - radiographs

Question 32

How does amelogenesis imperfecta present on radiographs?

Answer 32

You will fail to see a significant difference between the enamel & dentine layers

Question 33

How are the enamel crystals affected in hypoplastic amelogenesis imperfecta?

Answer 33

enamel crystals do not grow to the correct length

Question 34

How are the enamel crystals affected in hypomineralised amelogenesis imperfecta?

Answer 34

crystallites fail to grow in thickness & width

Question 35

How are the enamel crystals affected in hypomaturational amelogenesis imperfecta?

Answer 35

enamel crystals grow incompletely in thickness or width but to normal length with incomplete mineralisation

Question 36

what problems are associated with amelogenesis imperfecta?

Answer 36

- sensitivity - caries/acid susceptibility - poor aesthetics - poor OH (due to sensitivity) - delayed eruption - anterior open bite

Question 37

What are the solutions to help treat amelogenesis imperfecta?

Answer 37

- prevention !!! - composite veneers/composite wash - fissure sealants - metal onlays - SSCs - orthodontics

Question 38

Give examples of systemic disorders that are associated with enamel defects (not amelogenesis imperfecta):

Answer 38

- epidermolysis bullosa - down's syndrome - Prader-Willi - prophyria - Hurler's

Question 39

What are some anomalies of dentine structure that can occur?

Answer 39

- dentinogenesis imperfecta - dentine dysplasia - odontodysplasia - systemic disturbance

Question 40

How does dentine dysplasia present?

Answer 40

- normal crown morphology - amber radiolucency - pulpal obliteration - short constricted roots

Question 41

How does odontodysplasia present?

Answer 41

Localised arrest in tooth development: - thin layers of enamel & dentine - large pulp chambers - "ghost teeth"

Question 42

What are the different types of dentinogenesis imperfecta?

Answer 42

- Type I (odontogenesis imperfecta) - Type II (autosomal dominant - Brandywine

Question 43

what problems are associated with dentinogenesis imperfecta?

Answer 43

- aesthetics - caries / acid susceptibility - spontaneous abscess - poor teeth prognosis

Question 44

what solutions are used to treat patients with dentinogenesis imperfecta?

Answer 44

- prevention - composite veneers - overdentures (to cover compormised teeth) - removable prostheses - SSCs

Question 45

What anomalies of cementum structure exist?

Answer 45

- cleidocranial dysplasia - hypophosphatasia

Question 46

What is cleidocranial dysplasia?

Answer 46

hypoplasia of cellular component of cementum

Question 47

In which children is delayed eruption most common?

Answer 47

- pre-term & low birth-weight children - malnutrition

Question 48

In what general health syndromes/conditions is delayed tooth eruption seen?

Answer 48

- Down's Syndrome - hypothyroidism - hypopituitarism - cleidocranial dysplasia

Question 49

What can cause delayed exfoliation of teeth?

Answer 49

- infra-occlusion of teeth - hypodontia - ectopic permanent successors - trauma