Developmental Conditions of Teeth Flashcards Preview

Oral Pathology Exam 4 > Developmental Conditions of Teeth > Flashcards

Flashcards in Developmental Conditions of Teeth Deck (63):
1

What is the most common microdontia?

Peg lateral

2

What is the 2nd most common microdontia?

3rd Molars

3

In hypodontia/oligodontia what are the most common teeth that fail to form?

  • 3rd molars
  • Maxillary laterals
  • 2nd premolars

4

What is the etiology of hypodontia, in several cases?

Autosomal Dominant

5

What teeth are missing if you have an AXIN2 gene mutation? 

  • 2nd molars
  • 3rd molars
  • 2nd premolar
  • mandibular incisors
  • maxillary laterals 

6

What is a serious concern that requires follow up in those with the AXIN2 gene mutation?

Colonic polyps that will become malignant 

7

What is the etiology of Ectodermal Dysplasia?

X-linked Recessive 

Males

8

What is the appearance of the teeth in pts with Ectodermal Dysplasia?

Hypodontia = only a few peg shaped teeth

9

What is the most common supernumerary tooth?

Mesiodens 

  • between maxillary incisors 
  • Can impede eruption similar to an odontoma

10

What are distomolars?

4th molars

11

What are paramolars?

Supernummerary tooth buccal or lingual to molars

12

In what arch do 90% of supernumeraries occur in?

Maxillary - most are peg shaped

  • 10% in mandible - most with normal anatomy 

13

What diseases/syndromes are associated with supernumerary teeth?

  • Gardner Syndrome
  • Cleidocranial Dysplasia
  • Riga Fede Disease
    • Accessory natal teeth present at birth 
      • Crowns but no roots

14

  • "twinning"
  • Single tooth bud that didn't divide completely 
    • Bifid crown with shared root canal 
  • Have to count teeth to be able to tell what it is
    • normal tooth count

Gemination 

15

  • Two tooth buds
    • Separate root canals 
  • Lack of space/trauma pushed these together in early development and they conjoined 
  • Will have less teeth than normal 

Fusion

16

  • 2 teeth joined ONLY by cementum
  • Hypercementosis ridged two roots 
  • Separate dentin and enamel on biopsy

Concrescence

17

What is the etiology of a abnormally deviated root = dilaceration?

  • Abnormal shape from trauma
  • Hertwig's Root Sheath deviated producing a root that is deviated to the side in abnormal fashion 
  • No problems until extraction

 

18

What tooth is most commonly affected by dens invaginates/ dens in dente?

Maxillary lateral (14%)

19

What is the etiology of Dens invaginates?

  • Invagination of enamel epithelium from the lingual pit area forms a thin layer of enamel and dentin within the crown. 
  • Bacteria enters and creates pulp exposure, leaving the teeth vulnerable to occult caries = PA Pathosis 

20

  • Nodules of enamel on root trunk where it doesn't belong 
  • Ameloblasts get displaces
  • No periodontal attachment - can cause a perio defect

Enamel pearl

21

What population is mostly affected by Enamel Pearls?

Asains 

22

  • "bull tooth"
  • Elongated clinical crown + short roots
    • Bifurcation of roots occurs at the apex 
  • Rectangular shaped root and crown 
  • Big pulp canal

Taurodontism 

23

In what population does Taurodontism mostly occur?

Asians

24

What teeth are most commonly effected by taurodontism?

Mandibular molars

25

What is the pathogenesis of Taurodontism?

Late invagination of HERS

26

Shovel shaped incisors are most common on what teeth? 

Prominent marginal ridges on maxillary incisors 

 

27

Shovel shaped incisors are most common in what populations?

Asians + Native Americans 

normal anatomy for these ethnicities

28

Cingulum enlarged to for a cusp

Talon cusp

29

What tooth most commonly has a talon cusp?

Lateral incisor

30

What are some dental considerations for pts with talon cusps?

  • Pulp exposure if removed
  • Can interfere with occlusion

31

Cusp like projection in the central fossa

Dens Evaginatus

32

Dens Evaginatus is most common in what tooth? 

Occlusal of mandibular 2nd premolar

33

In what population is Dens Evaginatus common?

Asians

34

What are some dental considerations for a tooth with dens evaginatus?

Potential pulp exposure if removed

35

Where is the Cusp of Carabelli?

MesioPalatal 

Maxillary 1st Molar

36

Where is the protostylid cusp?

Mesiobuccal 

Mandibular 1st molar

37

In what population are protostylids ONLY found in?

Native Americans 

38

Where is the Cusp of Bolk?

Mesiobuccal 

Maxillary 2nd Molar

39

  • Looks like an enamel pearl that stays attached
  • Extension of enamel into the buccal furcation of a mandibular molar

Bikini Enamel

40

What is the dental consideration for pts with Bikini Enamel?

  • If the follicle that accompanies the extension gets inflammed in a partly erupted 3rd molar it can cause: 
    • Perio furcation
    • Buccal Bifurcation Cyst 
      • Squamous lined INFLAMMATORY follicular cyst

41

In what population does Bikini enamel occur?

Asians

42

  • Affects ONLY crowns or portions of crowns developing at the time of insult
  • Epithelium problem 
  • Ameloblasts are vulnerable to injury (hypoxia, chemicals, trauma, drugs) can become etched into the enamel 
  • Ameloblasts can recover and produce enamel again = Bands of Enamel

Enamel Hypoplasia: Environmental

43

What can cause Enamel Hypoplasia? (5)

  • Childhood infections
  • Congenital Syphilis
    • Hutchinson's incisors
    • Mulberry molars
  • Birth trauma/Cerebral Palsy
  • Vitamin Deficiency:
    • A = Enamel
    • C = Collagen
    • D = Deficient miineralization 
  • Maternal Diabetes

44

Affects ENTIRE Crown of BOTH Dentitions 

Epithelium problem 

Enamel Hypoplasia/Amelogenesis Imperfecta: Inherited

45

What are the Characteristics of Hypoplastic Amelogenesis Imperfecta?

  • Calcification, histology, and mineralization all normal 
  • Enamel matrix is thin
    • ​Spacing between teeth: due to enamel that should be present
    • Radiograph shows thin enamel - even in teeth that havent erupted yet
  • Small, yellow teeth with rough enamel surface, significant attrition, anterior open bite, and open contacts 
  • Teeth resemble crown preps, and some teeth can fail to erupt

46

What are the Characteristics of Hypocalcified Amelogenesis Imperfecta?

  • Normal thickness, but doesn't calcify right
  • Soft, shallow, brown discolored enamel
  • Enamel flakes off occlusal and incisal surfaces, and is easily damaged by dental tools and the cavitron
  • Shows up radiographically, not the normal RO of enamel, but similar to the opacity of dentin

47

What are the Characteristics of Hypomaturation Amelogenesis Imperfecta?

  • Normal thickness of matrix and normal calcification
  • Post-calcification - crystals of calcium fail to grow and interlock 
  • Discolored crowns with normal anatomy
    • Snow Caps
    • Mottled, opaque whie enamel with scattered areas of brown discoloration 
  • Can't penetrate with explorer, but vulnerable to cavitron 

48

What is the treatment for Hypoplastic and Hypocalcified Amelogenesis Imperfecta?

Veneers or Full Crowns 

49

What is the treatment for Hypomaturation Amelogenesis Imperfecta?

Might not need crowns, but be careful not to damage with dental instruments

50

Deciduous Tooth erupts looking chipped 

Turner Tooth

51

What is the pathogenesis of Turner's Tooth?

  • Focal Enamel Hypoplasia of Succedaneous tooth
  • Due to trauma, or periapical inflammation in the overlying deciduous tooth, not a systemic problem affecting amelobalsts 

52

What teeth are most commonly affected with Turner's Tooth?

Deciduous Molars and Maxillary Centrals 

53

What concentration of fluoride causes Flurosis?

> 1ppm

54

What are the characteristics of teeth with Fluorosis? 

  • Opaque, brown, chalky white areas
  • NOT hypoplastic, just discoloration 
  • Caries resistant 
  • No x-ray findings - enamel looks normal

55

What is the pathogenesis of Dentinogenesis Imperfecta?

  • CT Problem
    • Mesenchymal defect affecting dentin
  • Enamel is normal although teeth look bad
    • See dentin through translucent enamel

56

What teeth are affected in Dentinogenesis Imperfecta?

All teeth of BOTH dentitions, but teeth developing latest are least affected

57

What is the appearance of the teeth in Dentinogenesis Imperfecta?

  • Opalescent and brown/purple
  • Pulp Chambers completely lost
  • Roots thinner and shorter
  • Crowns bulbous/tulip shaped 

58

What are the dental considerations for DI?

  • Caries is not a problem - dentinal tubules are spared
  • A pt with DI is at NO risk of getting OI
    • But a pt with OI will get DI
  • Early attrition can lead to exposure of thin pulp horns which can lead to loss of crown length and PA pathosis  
  • Implants and Dentures are the recommended treatment

59

What is the etiology of Dentin Dysplasia Type I and II?

Autosomal Dominant

60

What are the characteristics of teeth in a person with Dentin Dysplasia Type I?

  • Rootless Teeth - absent/very short
  • Obliteration of pulp chamber
    • Like in DI

A image thumb
61

What are the characteristics of teeth in a person with Dentin Dysplasia Type II?

  • Crowns of deciduous teeth resemble Dentinogenesis Imperfecta
  • Permanent dentition looks normal 
  • X-ray shows thistle tube pulpe chambers + pulp stones

A image thumb
62

What are the characteristics of Regional Odontodysplasia?

Ghost Teeth

  • 1 or 2 teeth per quad
  • Pulp chambers are enormous
  • Thin enamel and dentin 
  • Many teeth don't erupt 
  • Subject to early pulp and PA pathosis for those that do erupt

A image thumb
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