Ch 2 - Abnormalities of Teeth 2

Question 1

How much of the tooth root is formed when emergence through the gingiva occurs?

Answer 1

2/3s of the root is developed

Question 2

What are 3 “local” conditions associated with delayed eruption?

Answer 2

1. supernumerary teeth 2. Regional odontodysplasia 3. Segmental Odontomaxillary Dysplasia

Question 3

What are 3 “systemic” conditions associated with delayed eruption?

Answer 3

1. Anemia 2. Celiac Dz 3. Cerebral palsy

Question 4

Some authors subdivide these non-erupted teeth into those that are obstructed by a physical barrier (impacted) and those that appear to exhibit a lack of eruptive force (________).

Answer 4

embedded

Question 5

Impaction of deciduous teeth is extremely rare, when it is seen which teeth are most likely involved? What pathologic process is most commonly the cause?

Answer 5

second molars…ankylosis

Question 6

HOLY S! One review of 2646 pericoronal lesions submitted to an active oral pathology service revealed that ___% of cases had pathologically significant lesions! A good reason to get them taken out…

Answer 6

32.9%

Question 7

infraocclusion, secondary retention, submergence, reimpaction, and reinclusion are all terms for:

Answer 7

ankylosis

Question 8

What is the most common tooth to have ankylosis?

Answer 8

mandibular primary first molar

Question 9

What is the difference between hypodontia and oligodontia?

Answer 9

Hypo: 1 or more teeth…Oligo: 6 or more teeth excluding 3rd molars

Question 10

How many genes are involved in odontogenesis?

Answer 10

more than 200

Question 11

What are the 7 implicated genes in hypodontia?

Answer 11

1. PAX9
2. MSX1
3. AXIN2
4. He-Zhao
5. LTBP3
6. EDA
7. WNT10A

Question 12

What are 5 syndromes (out of 39) associated with hypodontia?

Answer 12

1. Down 2. Ectodermal Dysplasia 3.Ehlers-Danlos 4.Gorlin 5.Otodental dysplasia

Question 13

What are 5 syndromes (out of 20) associated with hyperdontia?

Answer 13

1. Apert 2. Cleidocranial Dysplasia 3.Gardner 4.Down 5. Leopard

Question 14

Failure of teeth to form is one of the most common dental developmental abnormalities, with a reported prevalence of ___-___% in permanent teeth when absence of third molars is excluded. The prevalence increases to __% if third molars are considered.

Answer 14

3% to 10%…20%

Question 15

Hypodontia gender predominance?

Answer 15

A female predominance of approximately 1.5 : 1 is reported.

Question 16

Anodontia is rare with most cases arising from which condition?

Answer 16

hereditary hypohidrotic ectodermal dysplasia

Question 17

Which 3 teeth are LEAST likely to be congenitally missing?

Answer 17

max central incisors, mand first molars, mand canines

Question 18

In the deciduous dentition, 90% of missing teeth involve the _______ and _______

Answer 18

maxillary lateral incisors and mandibular incisors

Question 19

Mutation of the PAX9 gene creates an ___ pattern of oligodontia that can involve various teeth but most commonly affects WHICH TEETH?

Answer 19

AD…permanent molars

Question 20

Mutation of the MSX1 gene also is inherited as an
_____ trait. Those affected with this mutation
tend to demonstrate loss of the distal tooth of each
type, with more severely affected individuals also revealing anterior progression of the agenesis. In these patients, the most commonly missing teeth are the ________ and _______

Answer 20

AD…second premolars and third molars

Question 21

Which hypodontia gene mutation is associated with and average of approximately 12 missing teeth?

Answer 21

MSX1

Question 22

Which hypodontia gene deficiency was discovered in a large kindred from northwest China?

Answer 22

He-Zhao

Question 23

Which hypodontia gene mutation was discovered in a Pakistani lineage?

Answer 23

LTBP3

Question 24

The _____ gene is associated with a nonsyndromic X-linked pattern of hypodontia, which primarily affects the maxillary and mandibular central incisors, lateral incisors, cuspids, and premolars.

Answer 24

EDA (ANTERIOR TEETH most affected)

Question 25

Hypodontia associated with nonsyndromic mutation of the _____ gene appears limited to maxillary and mandibular lateral incisors and second premolars...weird

Answer 25

WNT10A

Question 26

*Which hypodontia gene mutation is associated with adenomatous polyps and colorectal carcinoma?

Answer 26

AXIN2

Question 27

Percent range of supernumerary teeth in whites? What race has a slightly higher percentage? Which race has a significantly higher rate compared to whites?

Answer 27

0.1-3.8%...Asian...American blacks: up to 9x more than whites

Question 28

Single-tooth hyperdontia occurs more frequently in the permanent dentition, and approximately 95% present in the ______ region.

Answer 28

maxillary anterior

Question 29

Unlike hypodontia, hyperdontia is positively correlated with ________ and exhibits a 2 : 1 ____ predominance.

Answer 29

macrodontia...male

Question 30

A supernumerary tooth in the maxillary anterior incisor region is termed a ?

Answer 30

mesiodens

Question 31

What are the two names for an accessory fourth molar?

Answer 31

distomolar or distodens

Question 32

A posterior supernumerary tooth situated lingually or buccally to a molar tooth is termed a ?

Answer 32

paramolar

Question 33

Supernumerary teeth are divided into _________ | (normal size and shape) or ________ (abnormal shape and smaller size) types

Answer 33

supplemental (normal size and shape)....rudimentary (abnormal shape and smaller size

Question 34

What are the 3 descriptive terms for rudimentary supernumerary teeth?

Answer 34

1. conical (small, peg-shaped) 2. tuberculate (barrel-shaped anterior with more than one cusp) 3.molariform (small premolar-like or molarlike)

Question 35

One of my new favorite Oral Path terms: On rare occasions, an affected patient can present with both hypodontia and hyperdontia - termed _______. Whats the pattern?

Answer 35

hypohyperdontia...missing mandibular incisors followed by second premolars; in contrast, supernumeraries in anterior maxilla followed by supplemental canines or maxillary premolars

Question 36

What is the term for a normal tooth that erupts in an abnormal location? (e.g. canine erupting between two premolars)...Which is associated with this - hyper or hypodontia?

Answer 36

dental transposition..associated with hypodontia

Question 37

Teeth present in newborns have been called ______ teeth; those arising within the first 30 days of life are designated ______ teeth - but now all should just be called ______

Answer 37

natal...neonatal...all should be called NATAL teeth

Question 38

What is the most common natal tooth?

Answer 38

mand ant incisior

Question 39

Patients with _______ exhibit an | increased prevalence of orthodontics-associated external root resorption.

Answer 39

oligodontia

Question 40

What is the term for traumatic ulcerations of the adjacent soft tissue that occur during breast feeding?

Answer 40

Riga-Fede disease

Question 41

Microdontia is associated strongly with _____dontia

Answer 41

hypodontia

Question 42

macrodontia often is seen in association with _____dontia

Answer 42

hyperdontia

Question 43

Which gender demonstrates a higher frequency of microdontia and hypodontia?

Answer 43

Female

Question 44

Which gender has agreater prevalence of macrodontia and hyperdontia?

Answer 44

male

Question 45

What are the 2 disorders associated with diffuse, true microdontia?

Answer 45

1. Down syndrome 2.pituitary dwarfism

Question 46

What is the inheritance pattern and percent range of prevelence for isolated microdontia of the max lat incisor (peg lateral)?

Answer 46

0.8-8.4%, AD

Question 47

5 disorders associated with diffuse MACROdontia

Answer 47

1. pituitary gigantism 2.otodental syndrome 3.XYY males 4. pineal hyperplasia with hyperinsulinism 5. Hemifacial hyperplasia

Question 48

Isolated macrodontia is reported to occur most frequently in which teeth?

Answer 48

incisors or canines