Test your basic knowledge |

Dentistry Tooth Development And Eruption

Subjects : health-sciences, dentistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What type of tissue is dentin - cementum - and alveolar bone?
Connective
May be confused as calculus deposit on root
Common on permanent molars or cingulum of anterior teeth
Enamel organ forms into cap - surrounding mass of dental papilla from the ectomesenchyme and surrounded by mass of dental sac also from the ectomesenchyme. Formation of the tooth germ.

2. What is matrix?
Abnormally large teeth
An extracellular substance that is partially calcified - yet serves as a framework for later calcification
Maturation
Bud stage

3. What is fusion?
Odontoblastic process
A bilayer rim that consists only IEE and OEE
Union of 2 adjacent tooth germs
Induction - proliferation

4. What hard tissue is can not have tissue formation after eruption?
Dentin secreting cells (odontoblats)
An extracellular substance that is partially calcified - yet serves as a framework for later calcification
In the cap stage
Enamel

5. What is the important acelluar structure that seperates the oral epithelium and the ectomesenchyme?
Dental papilla
The basement membrane
It disintegrates as the developing oral mucosa comes to line the oral cavity
Odontoblasts

6. What are the clinical ramifications?
8th week
Union of root structure of two or more teeth by cementum
After the crown is completely shaped and the tooth is starting to erupt into the oral cavity
Common on permanent molars or cingulum of anterior teeth

7. When does the tooth bud become a tooth germ?
An extracellular substance that is partially calcified - yet serves as a framework for later calcification
Common on permanent molars or cingulum of anterior teeth
Initiation
In the cap stage

8. What will the outer cells of the dental lamina differentiate into?
The stellate reticulum
Dentin and alveolar bone
Into odontoblasts
Dentin secreting cells (odontoblats)

9. What is the embryological background for dentin - cementum and alveolar bone?
Dental papilla
Future dentin and pulp tissue
Epithelial
Absence of single or multiple teeth

10. What stage does the dental tissues subsequently fully mineralize
Hereditary
Maturation
An extracellular substance that is partially calcified - yet serves as a framework for later calcification
Inner

11. What is amelogenisis?
Proliferation - differentiation - morphogenesis
9th to 10th weeks
There are none - they are lost with eruption
The apposition of the enamel matrix

12. What are the clinical ramifications of anodontia?
May cause disruption of occlusion and aesthetic problems - may need partial or full dentures - bridges - and/or implants
The ectomesenchyme
Apposition of the cementum
The primary tooth can now erupt into the oral cavity - the REE fuses with the oral epithelium - then enzymes from the REE disintegrate the central portion of the epithelial tissue leaving an epithelial tunnel for the tooth to erupt

13. What is enamel dysplasia?
Commonly affects the permanent maxillary lateral incisor. tooth may have deep lingual pit and need endodontic therapy
Faulty development of enamel from interference involving ameloblasts
Traumatic injury or crowding of teeth
Common on permanent molars or cingulum of anterior teeth

14. What stage does anodontia occur?
Commonly involves permanent maxillary lateral incisor and 3rd molars
Osteoblasts
9th to 10th weeks
Initiation stage

15. What is the time span for the bell stage?
The enamel organ
Cementoid
11th to 12th weeks
Tall columnar cells

16. Where is the dental sac originally derived from?
Epithelial
The primary tooth can now erupt into the oral cavity - the REE fuses with the oral epithelium - then enzymes from the REE disintegrate the central portion of the epithelial tissue leaving an epithelial tunnel for the tooth to erupt
The ectomesenchyme
Outer

17. What are the cell layers found in the enamel organ in the bell stage?
Odontogenesis
Dental papilla
Commonly involves permanent maxillary lateral incisor and 3rd molars
The outer enamel epithelium - the inner enamel epithelium - the stellate reticulum - and the stratum intermedium

18. What are the developmental disturbances of the cap stage?
Differentiation of enamel organ into bell with four cell types and dental papilla into two cell types.
Dens in dente - gemination - tubercle - and fusion
Growth of the dental lamina into bud that penetrates growing ectomesenchyme
The primordium of the pulp

19. What are the 2 layers in the dental papilla within the concavity of the enamel organ?
The outer cells of the dental papilla and the central cells of the dental papilla
Absence of single or multiple teeth
The primordium of the pulp
Imbrication lines of von Ebner

20. How is the dentinocemental junction formed?
Trauma - pressure or metabolic disease
As a result of the apposition of cementum over dentin
Growth of the dental lamina into bud that penetrates growing ectomesenchyme
Proliferation - differentiation - morphogenesis

21. The remaining ectomesenchyme surrounding the outside of the enamel organ condenses into what?
The dental sac
Proliferation
The outer enamel epithelium - the inner enamel epithelium - the stellate reticulum - and the stratum intermedium
Hereditary

22. What are succedaneous teeth?
Pressure on the area
Permanent teeth formed with primary predecessors - the anterior teeth and the premolars
Trauma - pressure or metabolic disease
As a result of the apposition of cementum over dentin

23. What happens to the thickened non tooth producing portions of the dental lamina eventually?
Dental tissues fully mineralize to their mature levels.
It disintegrates as the developing oral mucosa comes to line the oral cavity
Bud stage
Osteocytes

24. What hard tissue has vascularity?
Growth of the dental lamina into bud that penetrates growing ectomesenchyme
Morphogenesis
The basement membrane
Alveolar bone

25. What is the main process involved in initiation?
Dental papilla
Large single rooted tooth with one pulp cavity and exhibits 'twinning' in crown area. normal number of teeth in dentition. may cause problems in appearance and spacing
There is unequal growth in different parts of the tooth bud
Induction

26. What are supernumerary teeth?
Development of one or more extra teeth
Induction - proliferation
Proliferation - differentiation - morphogenesis
The primary tooth can now erupt into the oral cavity - the REE fuses with the oral epithelium - then enzymes from the REE disintegrate the central portion of the epithelial tissue leaving an epithelial tunnel for the tooth to erupt

27. What causes the induction of the preameloblasts to differentiate into ameloblasts?
Enamel organ forms into cap - surrounding mass of dental papilla from the ectomesenchyme and surrounded by mass of dental sac also from the ectomesenchyme. Formation of the tooth germ.
The cervical loop
The disintegration of the basement membrane allows the preameloblasts to come into contact with the newly formed predentin
Cementocytes

28. What are the etiological factors of tubercle?
Large tooth with two pulp cavities. one fewer tooth in dentition. may cause problems in appearance and spacing
The apposition of the enamel matrix
Displacement of ameloblasts to root surface
Trauma - pressure or metabolic disease

29. What is macrodontia?
Abnormally large teeth
Abnormally small teeth
The ectomesenchyme
A mineralized cylinder - the dentinal tubule

30. What is the predominate process of the cap stage?
Morphogenesis
An extracellular substance that is partially calcified - yet serves as a framework for later calcification
Permanent teeth formed with primary predecessors - the anterior teeth and the premolars
Outer

31. Passive eruption
The enamel organ is compressed
There is unequal growth in different parts of the tooth bud
6th to 7th weeks
When the gingiva recedes and no actual tooth movement takes place

32. The stratum intermediate is located inner or outer?
Occurs commonly between the maxillary centrals - distal to the 3rd molars and premolar region. may cause crowding - failureof normal eruption and disruption of occlusion
The outer enamel epithelium - the inner enamel epithelium - the stellate reticulum - and the stratum intermedium
Inner
Common on permanent molars or cingulum of anterior teeth

33. What is the time span for the cap stage?
The enamel organ is compressed
Extra cusp due to effects on enamel organ
Epithelial rests of Malassez
9th to 10th weeks

34. What is microdontia?
Abnormally small teeth
Hereditary
The successional dental lamina - an extension of the dental lamina that extends out lingually to the primary tooth germs
Imbrication lines of von Ebner

35. How many types of cells are found in the enamel organ in the bell stage?
Enamel organ invaginates into the dental papilla
The enamel organ
Differentiation
4 types

36. What are the mature cells for cementum?
A mineralized cylinder - the dentinal tubule
The primary tooth can now erupt into the oral cavity - the REE fuses with the oral epithelium - then enzymes from the REE disintegrate the central portion of the epithelial tissue leaving an epithelial tunnel for the tooth to erupt
When the gingiva recedes and no actual tooth movement takes place
Cementocytes

37. What will the dental sac give rise to?
Hereditary
Proliferation
Enamel organ invaginates into the dental papilla
The cementum - PDL - and alveolar bone

38. Do odontoblasts start their secretion of matrix before the ameloblasts?
Yes - this is why the dentin is thicker in the mature tooth structure than the enamel
Differentiation
Growth of the dental lamina into bud that penetrates growing ectomesenchyme
The apposition of the enamel matrix

39. What is the cementum matrix called?
Induction
Epithelial
Cementoid
Dental tissues secreted as matrix in successive layers.

40. What is the site for the future dentioenamel junction?
After the crown is completely shaped and the tooth is starting to erupt into the oral cavity
Dentinogenesis - Which is the apposition of dentin matrix - or predentin - on the other side of the basement membrane
The basement membrane that seperates the enamel organ and dental papilla
Osteoblasts

41. In the cap stage the tooth bud does not grow - what happens?
Future dentin and pulp tissue
There is unequal growth in different parts of the tooth bud
Hereditary in localized form. endocrine dysfunction is complete
The ectomesenchyme

42. What conveys communications between the cells of the enamel organ - the dental papilla - and the dental sac allowing tissue interactions?
The basement membrane
May be confused as calculus deposit on root
A mineralized cylinder - the dentinal tubule
Hereditary

43. What are the incremental lines for enamel?
The primary tooth can now erupt into the oral cavity - the REE fuses with the oral epithelium - then enzymes from the REE disintegrate the central portion of the epithelial tissue leaving an epithelial tunnel for the tooth to erupt
Lines of Retzuis
11th to 12th weeks
Absence of single or multiple teeth

44. When the undifferentiated cells of the dental sac come into contact with the root dentin they differentiate into what?
Cementoblasts
Dental tissues fully mineralize to their mature levels.
Union of root structure of two or more teeth by cementum
Oral epithelium

45. What are the clinical ramifications of micro/macrodontia?
Enamel pearl - enamel dysplasia - and concresence
Commonly involves permanent maxillary lateral incisor and 3rd molars
Epithelial rests of Malassez
Enamel organ

46. What happens during the maturation stage?
Enamel organ invaginates into the dental papilla
The dental lamina
Large single rooted tooth with one pulp cavity and exhibits 'twinning' in crown area. normal number of teeth in dentition. may cause problems in appearance and spacing
Dental tissues fully mineralize to their mature levels.

47. What is the predominate process in the bell stage?
Differentiation
Odontoclasts
Commonly affects the permanent maxillary lateral incisor. tooth may have deep lingual pit and need endodontic therapy
Absence of single or multiple teeth

48. What are the etiological factors for fusion?
Bud stage
Ameloblasts
Abnormally large teeth
Pressure on the area

49. What is anodontia?
Odontoclasts
Dental papilla
Cementoblasts
Absence of single or multiple teeth

50. What happens during the cap stage?
Apposition of the cementum
Enamel organ forms into cap - surrounding mass of dental papilla from the ectomesenchyme and surrounded by mass of dental sac also from the ectomesenchyme. Formation of the tooth germ.
Osteocytes
Yes - this is why the dentin is thicker in the mature tooth structure than the enamel