Tooth Abnormalities

Question 1

When do crowns of deciduous teeth develop?

Answer 1

14th week of gestation until 12 months of age

Question 2

When do crowns of permanent teeth develop?

Answer 2

6 months until 15 years

Question 3

Enamel defects in permanent teeth caused by periapical inflammatory disease of the overlying deciduous tooth is called what?

Answer 3

Turner’s Hypoplasia

*Most commonly in permanent bicuspids

Question 4

What is the optimum fluoridation level in drinking water?

Answer 4

0. 7 ppm

* excess fluoride causes fluorosis

Question 5

What are the two tooth morphologies that are typical of congenital syphilis?

Answer 5

1-Hutchinsons incisors (straight edge screw-driver)

2-Mulberry molars

Question 6

What are the 3 components of the Hutchinsons triad?

Answer 6

1-Hutchinsons incisors
2-Keratitis (corneal scarring)
3-8th nerve deafness

*may also see saddle nose

Question 7

Loss of tooth structure caused by tooth on tooth contact is called?

Answer 7

Attrition

Question 8

Mechanical wearing away of tooth structure is called?

Answer 8

Abrasion

*often tooth brushing)

Question 9

Both attrition and abrasion together such as with chewing tobacco is called what?

Answer 9

Demastication

Question 10

Loss of tooth structure caused by a nonbacterial chemical process is called?

Answer 10

Erosion

*Also called Corrosion

Question 11

Erosion of dental structures due to exposure to gastric secretions is called?

Answer 11

Perimolysis

Question 12

Loss of tooth structure from occlusal stresses and repeated tooth flexure is called?

Answer 12

Abfraction or Non-carious cervical lesions

Question 13

Teeth that are anchored in bone are referred to as?

Answer 13

Ankylosis

Question 14

A single enlarged tooth or joined tooth in which the tooth count is normal when the anomalous tooth is counted as one is called?

Answer 14

Gemination

Question 15

Single enlarged tooth or joined tooth in which the tooth count reveals a missing tooth when the anomalous tooth is counted as one is called?

Answer 15

Fusion

Question 16

Union of adjacent teeth by cementum (no dentin involvement) it is called?

Answer 16

Concrescence

Question 17

When a root is bent, it is referred to as?

Answer 17

Dilaceration

Question 18

An additional cusp found on the lingual of an incisor is called?

Answer 18

Talons cusp

*Extra cusps are called accessory cusps

Question 19

An outcropping, usually found bilaterally on premolars in association with shovel shaped incisors is called what?

Answer 19

Dens Evaginatus

*close to 100% in native americans

Question 20

What are two characteristics of the rare hereditary hypohidrotic ectodermal dysplasia?

Answer 20

1-No or very few sweat glands

2- Anodontia or very few teeth

Question 21

Hypodontia is a lack of one or more teeth. Lack or 6 or more is called?

Answer 21

Oligodontia

Question 22

What are the three most commonly congenitally missing teeth?

Answer 22

1-3rd molars
2-2nd premolars
3-Lateral incisors

Question 23

What is the most common form of hyperdontia or supernumerary teeth?

Answer 23

Mesiodens. Extra tooth between or around maxillary incisors

Question 24

What are two major characteristics of cleidocranial dysplasia?

Answer 24

1-Hypoplastic (missing) clavicles

2-Supernumerary impacted teeth

Question 25

Switched teeth are called?

Answer 25

Dental transposition

Question 26

Which disease is characterized by premature tooth eruption and traumatic ulcerations of adjacent soft tissues?

Answer 26

Riga-Fede

Question 27

What 3 teeth are most frequently impacted?

Answer 27

1-Mandibular 3rd molars 2-Maxillary 3rd molars 3-Maxillary canine

Question 28

A deep surface invagination of the crown or root that is lined by enamel is called?

Answer 28

Dens-in-dente

Question 29

What is the order of the 5 frequencies in which dens-in-dente occur?

Answer 29

``` 1-permanent lateral incisors 2-central incisors 3-premolars 4-canines 5-molars ```

Question 30

What 3 teeth most frequently have dilacerated roots?

Answer 30

1-mandibular 3rd molars 2-maxillary 2nd premolars 3-mandibular 2nd molars

Question 31

An enlargement of the body and pulp chamber of a multi-rooted tooth, with apical displacement of the pulpal floor is called what?

Answer 31

Taurodontism

Question 32

What 3 syndromes are associated with Taurodontism?

Answer 32

1-Kleinfelters syndrome 2-Amelogensis imperfecta 3-Tricho-dento-osseous syndrome

Question 33

In addition to Taurodontism, what three other things characterize Tricho-dento-osseous syndrome?

Answer 33

1-Kinky hair 2-Osteosclerosis 3-Brittle nails

Question 34

Non neoplastic deposition of excessive cementum that is continuous with the normal radicular cementum is called what?

Answer 34

Hypercementosis *may be caused by occlusal trauma or adjacent inflammation

Question 35

What disease is strongly associated with generalized hypercementosis?

Answer 35

Paget's Disease

Question 36

Developmental alterations in the structure of enamel in the absence of a systemic disorder is known as?

Answer 36

Amelogensis imperfecta

Question 37

What are the 3 types of Amelogensis imperfecta?

Answer 37

1-Hypoplastic 2-Hypocalcified 3-Hypomaturation

Question 38

Inadequate deposition of enamel matrix in pitting is what type of amelogenesis imperfecta?

Answer 38

Hypoplastic *yellow-brown dentin color to the tooth

Question 39

Enamel matrix is laid down and teeth are normal in shape but enamel is soft and chips away resulting in snow-capped, white opaque enamel resulting in what type of amelogenesis imperfecta?

Answer 39

Hypomaturation *Surface enamel is agar brown. Is x-linked but varies

Question 40

Which type of amelogensis imperfecta lays down matrix but it is not mineralized giving both pitting and snow capped look to the soft and easily lost enamel?

Answer 40

Hypocalcified *yellow-brown or orange and becomes black with rapid calculus apposition

Question 41

The Hereditary developmental disturbance of dentin in the absence of any systemic disorder is called?

Answer 41

Dentinogenesis imperfecta

Question 42

Which mutation is associated with dentinogenesis imperfecta?

Answer 42

Dentin sialophosphoprotein gene (DSPP)

Question 43

If dentinogenesis imperfecta is suspected and the patient has blue sclera, what is it?

Answer 43

Osteogenesis imperfecta with opalescent teeth *mutation of the COL1A1 or COL1A2

Question 44

What 4 characteristics are typical of dentinogenesis imperfecta teeth in a radiograph?

Answer 44

1-Bulbous crowns 2-Cervical constriction 3-Thin roots 4-Early obliteration of canals and pulp chamber

Question 45

Typically in baby teeth, what is it called when the thinness of enamel dramatically enlarges the pulp?

Answer 45

Shell teeth *does not have apically displaced floor

Question 46

Which type of dentin dysplasia has "rootless teeth", clinically normal crowns, and looks like a stream flowing around boulders in a microscope?

Answer 46

Type I dentin dysplasia *Autosomal dominant

Question 47

Which type of dentin dysplasia is similar to DI but has altered pulp anatomy (thistle tube-shaped and pulp stones)?

Answer 47

Type II dentin dysplasia *Autosomal dominant

Question 48

A localized, non-hereditary developmental abnormality of teeth resulting in "ghost teeth" is called what?

Answer 48

Regional Odontodysplasia