Question (1): Enumerate with drawings different types of root canals

(5 marks)

(5 marks)

(10 marks)

1. 
   H-file cuts dentin more efficiently than K-file ( ).
   
2. 
   File size 25 is blue in colour ( ).
   
3. 
   Nickel Titanium material has high modulus of elasticity ( ).
   
4. 
   Flex-O-file has triangular cross section ( ).
   
5. 
   K-file is more flexible than K-reamer ( ).
   
6. 
   Golden medium system offers intermediate sizes between ISO files ( ).
   
7. 
   Ultrasonic instruments are ideal tools for canal shaping ( ).
   
8. 
   Ledge formation results from using non-flexible instruments in curved canals ( ).
   
9. 
   Cutting 1mm from tip of file no 10 will generate file no 12 ( ).
   
10. 
    Dangerous zone area of minimal dentin thickness in molars is located toward the furcation area ( ).
    

(30 marks)

1. 
   Apical third root cross section of upper central incisor is:
   

1. 
   Round
   
2. 
   Oval
   
3. 
   triangular
   
4. 
   ovoid
   

2. 
   The longest tooth in the arch is:
   

1. 
   Upper central incisor
   
2. 
   Lower canine
   
3. 
   Upper first molar
   
4. 
   Upper canine
   

3. 
   Cavity outline form in molars is located:
   

1. 
   in mesial half
   
2. 
   in distal half
   
3. 
   in the center of the tooth
   
4. 
   shifted lingually
   

4. 
   Maxillary premolar contains:
   

1. 
   1 pulp horn
   
2. 
   2 pulp horns
   
3. 
   3 pulp horns
   
4. 
   4 pulp horns
   

5. 
   Indications of endodontic therapy include:
   

b) Non-strategic tooth

c) Vertical fracture

d) None of the above

6. 
   From the mesial view of maxillary central incisor we can see :
   

1. 
   Wide pulp chamber with 3 pulp horns
   
2. 
   Pulp chamber is pointed incisally and widen cervically
   
3. 
   Triangular in shape with the base towards the labial and apex towards the palatal
   
4. 
   b&c
   

7. 
   The root canal system configuration is always type I except in :
   

1. 
   Maxillary central incisor
   
2. 
   Maxillary canine
   
3. 
   Maxillary lateral incisor
   
4. 
   Mandibular central incisor
   

8. 
   Cross section in the root cervical third of maxillary canine is :
   

1. 
   Oval
   
2. 
   Triangular
   
3. 
   Trapezoid
   
4. 
   Rhomboid
   

9. 
   70% of maxillary first premolar root canal configuration is:
   

1. 
   Type I
   
2. 
   Type II
   
3. 
   Type III
   
4. 
   Type IV
   

10. 
    Maxillary first molar may contain an extra canal called :
    

1. 
   MB2
   
2. 
   D2
   
3. 
   P2
   
4. 
   DB2
   

11. 
    Convenience form depends on :
    

1. 
   Size of the pulp chamber
   
2. 
   Shape of the pulp chamber
   
3. 
   Number of root canals
   
4. 
   All of the above
   
5. 
   None of the above
   

12. 
    Base of the triangle-shaped access cavity preparation of maxillary molars lies:
    

1. 
   Mesially
   
2. 
   Buccally
   
3. 
   Distally
   
4. 
   Palatally
   

13. 
    The coronal pulp is formed of :
    

b) Pulp chamber and pulp horns

c) Pulp chamber and accessory canals

d) Root canal and accessory canals

14. 
    The basic phases of endodontic therapy include all of the following except :
    

1. 
   Diagnostic
   
2. 
   Preparatory
   
3. 
   Irrigation of the cavity
   
4. 
   Obliteration
   

15. 
    Endodontics is a branch of dentistry concerned with:
    

1. 
   Pulp diseases.
   
2. 
   Periapical diseases.
   
3. 
   Pulp and periapical diseases.
   
4. 
   Pain due to pulp injury.
   

16. 
    Outline form of mandibular premolars is:
    

1. 
   Round
   
2. 
   Ovoid
   
3. 
   Oval
   
4. 
   Triangular
   

17. 
    Pulp chamber of upper central incisor is :
    

1. 
   Wider in buccolingual dimension.
   
2. 
   Wider in mesiodistal dimension.
   
3. 
   Has two pulp horns.
   
4. 
   oval in shape.
   

18. 
    Diagnostic materials and devices include:
    

1. 
   Vitality testing.
   
2. 
   Tooth slooth.
   
3. 
   Radiography.
   
4. 
   Visual aids.
   
5. 
   All of the above.
   

19. 
    Instruments for access cavity preparation include:
    

1. 
   Burs.
   
2. 
   Exploring instruments.
   
3. 
   Barbed broach.
   
4. 
   a& b.
   
5. 
   None of the above.
   

20. 
    Barbed broach is used for:
    

1. 
   Exploring canals orifices.
   
2. 
   Enlarging root canals.
   
3. 
   Extirpating pulp tissue.
   
4. 
   Determination of the tooth length.
   

21. 
    K File is:
    

1. 
   Fabricated by twisting counter clock wise.
   
2. 
   Square in cross section.
   
3. 
   Used in filing and reaming action.
   
4. 
   All of the above.
   

22. 
    Which of the following is true for K Reamer:
    

1. 
   Used for reaming only.
   
2. 
   Used for filing and reaming.
   
3. 
   Has square cross section.
   
4. 
   Is fabricated by machine grinding.
   

23. 
    H File is:
    

1. 
   Fabricated by machining (grinding).
   
2. 
   Used for filing only.
   
3. 
   Triangular in cross section
   
4. 
   All of the above
   
5. 
   a & b
   

24. 
    Flexibility is increased by:
    

1. 
   Decreasing the cross section.
   
2. 
   Decreasing the length.
   
3. 
   Increasing the length.
   
4. 
   increasing the cross section.
   
5. 
   a&c
   
6. 
   b&d
   

25. 
    The most flexible instruments are :
    

1. 
   Nickel-titanium instruments.
   
2. 
   Stainless steel instruments.
   
3. 
   Carbon steel instruments.
   
4. 
   a& c only.
   

26. 
    According to ISO standardization the length of the cutting part is:
    

1. 
   0.02 mm.
   
2. 
   21 mm.
   
3. 
   0.32 mm.
   
4. 
   16 mm.
   

27. 
    According to ISO standardization all the following is right except:
    

1. 
   Taper is 0.02 mm/mm.
   
2. 
   Tip design is 75 ± 15 degrees.
   
3. 
   Linear increase in D0 by 0.05 mm from #15 to 60.
   
4. 
   D16=D0+ 0.21 mm.
   

28. 
    Number 15 on the handle of file indicates that:
    

1. 
   The increase in diameter from D0 to D16 is 0.15 mm.
   
2. 
   The length from D1 to D16 is 15 mm.
   
3. 
   Diameter at D0 =0.15 mm.
   
4. 
   The length from the working tip to the file handle is 15 mm.
   

29. 
    Removal of pulp horn is necessary to avoid:
    

1. 
   Missing canal
   
2. 
   Ledge and perforation
   
3. 
   Discoloration
   
4. 
   All of the above
   

30. 
    Cross section of K-flex file is:
    

1. 
   Rhomboid
   
2. 
   Triangular
   
3. 
   Round
   
4. 
   Square
   

Model Answer

1. 
   ( True)
   
2. 
   ( False )
   
3. 
   ( False )
   
4. 
   ( True)
   
5. 
   ( False)
   
6. 
   (True)
   
7. 
   (False)
   
8. 
   (True)
   
9. 
   (True )
   
10. 
    (True )
    

1. 
   A
   
2. 
   D
   
3. 
   A
   
4. 
   B
   
5. 
   D
   
6. 
   B
   
7. 
   D
   
8. 
   A
   
9. 
   A
   
10. 
    A
    
11. 
    E
    
12. 
    B
    
13. 
    B
    
14. 
    C
    
15. 
    C
    
16. 
    B
    
17. 
    B
    
18. 
    E
    
19. 
    D
    
20. 
    C
    
21. 
    D
    
22. 
    A
    
23. 
    E
    
24. 
    F
    
25. 
    A
    
26. 
    D
    
27. 
    D
    
28. 
    C
    
29. 
    C
    
30. 
    A