Regarding maxillary canine, all is true

1. 
   Regarding maxillary canine, all is true except:
   

1. 
   It is the longest tooth in dental arch.
   
2. 
   Has 3 pulp horns.
   
3. 
   Always found with one root canal.
   
4. 
   Access cavity preparation is oval in shape.
   

2. 
   Type II root canal system refers to:
   

1. 
   1 canal, 1 Orifice, 1 Foramen.
   
2. 
   2 canal, 2 Orifice, 2 Foramen.
   
3. 
   2 canal, 2 Orifice, 1 Foramen.
   
4. 
   2 canal, 1 Orifice, 2 Foramen.
   

3. 
   Maxillary first premolars:
   

1. 
   Most frequently have two roots
   
2. 
   Access cavity preparation is triangular in shape
   
3. 
   Have three pulp horns
   
4. 
   Cross-sections at cervical line shows pulp chamber wider mesiodistally that buccolingually.
   

4. 
   Root canal system in distal root of mandibular second molar is most frequently:
   

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

5. 
   Endodontic treatment is indicated in cases with:
   

1. 
   Massive root resorption
   
2. 
   Vertical root fracture
   
3. 
   Large long standing radiolucencies
   
4. 
   None of the above
   

6. 
   Smallest tooth in the dental arch is:
   

1. 
   Maxillary lateral incisor
   
2. 
   Mandibular central Incisor
   
3. 
   Mandibular lateral Incisor
   
4. 
   Mandibular second premolar
   

7. 
   2 canals are never found in:
   

1. 
   Maxillary canine
   
2. 
   Mandibular central incisor
   
3. 
   Mandibular lateral Incisor
   
4. 
   Mandibular first premolar
   

8. 
   In mandibular molars, access cavity preparation is:
   

1. 
   Within the confines of the mesial half of the crown
   
2. 
   Could be triangular
   
3. 
   Could be rhomboid
   
4. 
   All of the above
   

9. 
   Type I root canal system is most frequently found in:
   

1. 
   Maxillary second premolar
   
2. 
   Maxillary central incisor
   
3. 
   Mandibular first premolar
   
4. 
   Mandibular lateral Incisor
   

10. 
    Flaring during access cavity preparation can be done with:
    

1. 
   Round bur
   
2. 
   Endo-Z bur
   
3. 
   Fissure bur
   
4. 
   b, c
   

11. 
    First instrument to be used for coronal access cavity preparation is:
    

1. 
   Endo-Z bur
   
2. 
   Safe-ended stone
   
3. 
   Round bur
   
4. 
   a, b
   

12. 
    Apex of the triangle-shaped access cavity preparation of incisors is:
    

1. 
   Mesial
   
2. 
   Distal
   
3. 
   Incisal
   
4. 
   Cervical
   

13. 
    Access cavity preparation of all the following is oval or ovoid except:
    

1. 
   Maxillary canine
   
2. 
   Mandibular canine
   
3. 
   Mandibular first molar
   
4. 
   Maxillary second premolar
   

14. 
    Bayonet curvature of the roots is common in:
    

1. 
   Maxillary canine
   
2. 
   Maxillary second premolar
   
3. 
   Mandibular canine
   
4. 
   Mandibular second premolar
   

15. 
    Base of the triangle-shaped access cavity preparation of maxillary molars lies:
    

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

16. 
    Deroofing of the pulp chamber is important to:
    

1. 
   Locate the canals
   
2. 
   Decrease discoloration of the teeth
   
3. 
   Facilitate accessibility to the canals
   
4. 
   All of the above
   

17-The third phase of endodontic therapy is:

1. 
   Diagnostic phase.
   
2. 
   Obliteration phase.
   
3. 
   Preparatory phase.
   
4. 
   None of the above.
   

18-A case of vertical fracture has :

a)Moderate prognosis.

b)Hopless prognosis.

c)Good prognosis.

d)A good prognosis according to the age of the patient.

a)Is contraindicated for endodontic treatment.

b)Might have poor prognosis.

c)Will usually heal after treatment.

d)None of the above.
20-A tooth with large rapidly growing radiolucency:

a)Is out of the scope of endodontic treatment.

b)Will usually heal after treatment.

C)Have poor prognosis.

d)None of the above.
21-Prognosis of endodontic treatment in elderly patients is better than young patient

Is due to:

a)Tighter apical foramina.

b)Lack of completely patent auxiliary root canals.

c)Dense periapical bone.

d)All of the above

21. 
    Type IV root canal system refers to:
    
    1. 
       1 root canal, 1 orifice and 1 apical foramen.
       
    2. 
       1 root canal , 1 orifice and 2 apical foramina .
       
    3. 
       2 root canal, 2 orifice and 1 apical foramen.
       
    4. 
       2 root canal, 2 orifice and 2 apical foramina.
       

21. 
    Cervical section of the root canal in a maxillary central incisor is:
    

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

21. 
    The root canal system of maxillary canine is:
    
    1. 
       100 % type I.
       
    2. 
       100 % type III.
       
    3. 
       75 % type II.
       
    4. 
       85 % type I
       

21. 
    The root canals in the mandibular incisors are:
    
    1. 
       Wider mesiodistally than labiolingually.
       
    2. 
       Wider labiolingually than mesiodistally.
       
    3. 
       Most frequently type III canal system.
       
    4. 
       None of the above.
       

21. 
    The first mandibular premolar usually has:
    
    1. 
       One root with one root canal.
       
    2. 
       One root with two root canals.
       
    3. 
       Two roots with two canals that merge apically.
       
    4. 
       Two roots with two separate canals.
       
22. 
    Which of the following burs is not recommended to use during deroofing of the pulp chamber:
    
    1. 
       Safe ended bur.
       
    2. 
       Round bur.
       
    3. 
       Inverted cone bur.
       
    4. 
       None of the above.
       

21. 
    The outline of an access cavity in mandibular molars is:
    
    1. 
       Triangular in shape.
       
    2. 
       Square in shape.
       
    3. 
       Ovoid in shape.
       
    4. 
       None of the above.
       

21. 
    In the first maxillary molar, the second mesiobuccal canal (MB2) is located:
    

1. 
   In a palatal direction relative to MB1 canal.
   
2. 
   In a mesiobuccal direction relative to MB1 canal.
   
3. 
   In a mesiopalatal direction relative to MB1 canal.
   
4. 
   In a distopalatal direction relative to MB1 canal.
   

21. 
    The outline of the access cavity of maxillary premolars is:
    

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

31- In a mesial view, the palatal root of the maxillary molars curves:

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

32- A straight line access to the root canal ensures:

1. 
   Conservation of tooth structure.
   
2. 
   Unroofing of the pulp chamber.
   
3. 
   Guiding the instrument tips.
   
4. 
   None of the above.
   

33- Convenience form is a modification of the cavity to achieve:

1. 
   Complete authority over the enlarging instrument.
   
2. 
   Direct access to the apical foramen.
   
3. 
   Unobstructed access to the canal orifices.
   
4. 
   All of the above.
   

34-The outline of an access cavity in maxillary molars with four root canals is:

1. 
   Triangular in shape.
   
2. 
   Rhomboidal in shape.
   
3. 
   Ovoid in shape.
   
4. 
   None of the above.
   

35- Out line form of the access cavity in maxillary canine is :

a) Round

b) Trapezoid

c) Triangular

d) None of the above

36- Type III root canal sytem has:

1. 
   One orifice ,one canal and two apical foramina
   
2. 
   Two orifices, two canals and two apical foramina
   
3. 
   One orifice ,one canal and one apical foramen
   
4. 
   Two orifices, one canal and two apical foramina
   

37- - Maxillary lateral incisor has:

1. 
   Type I root canal system
   
2. 
   Type III root canal system
   
3. 
   Type IV root canal system
   
4. 
   All of the above
   

38- Endodontic treatment is contraindicated if :

1. 
   There is Insufficient periodontal support
   
2. 
   Non-strategic Tooth.
   
3. 
   c -Massive Resorption.
   
4. 
   d- All of the above
   

39- The part of the pulp tissue in the root is called :

1. 
   Coronal pulp
   
2. 
   Pulp horn
   
3. 
   Radicular pulp
   
4. 
   None of the above
   

40- Mandibular central Incisor may have:

1. 
   Three canals
   
2. 
   One canal
   
3. 
   Two canals
   
4. 
   b or c
   

1. 
   Buccally
   
2. 
   Incisally
   
3. 
   Lingually
   
4. 
   Distally
   

42-Factors affecting outline form of an endodontic access cavity :

1. 
   Age of patient
   
2. 
   Number of root canals
   
3. 
   Size of pulp chamber
   
4. 
   All of the above
   

43- Entrance in premolars is always gained through:

1. 
   Buccal surface
   
2. 
   Mesial surface
   
3. 
   Occlusal surface
   
4. 
   Distal surface
   

44- Out line form of the access cavity in mandibular premolars

1. 
   Oval
   
2. 
   Trapezoid
   
3. 
   c-Triangular
   
4. 
   None of the above
   

45- The second phase of endodontic therapy is called :

1. 
   Diagnosis
   
2. 
   Obliteration
   
3. 
   Preparation
   
4. 
   Restoration
   

46- Type IV root canal system has:

1. 
   One orifice ,one canal and one apical foramen
   
2. 
   Two orifices, one canal and two apical foramina
   
3. 
   One orifice ,one canal and two apical foramina
   
4. 
   Two orifices, two canals and two apical foramina
   

47- Maxillary canine has

1. 
   One root with apical cuvature
   
2. 
   Three roots
   
3. 
   One pulp horn
   
4. 
   a and c
   
5. 
   None of the above
   

1. 
   Triangular
   
2. 
   Round
   
3. 
   Rhomboid
   
4. 
   a or c
   
5. 
   a or b
   

49- The fourth canal in maxillary first molar is found in:

1. 
   Palatal root
   
2. 
   Mesibuccal root
   
3. 
   Distbuccal root
   
4. 
   None of the above
   

50- Average length of mandibular canine is:

a) 18.5 mm

b) 25.2 mm

c) 32 mm

d) 20mm
51- Principles of endodontic access cavity preparation :

1. 
   Outline form
   
2. 
   Convenience form
   
3. 
   Removal of carious dentine and defective resrorations
   
4. 
   Irrigation of the cavity
   
5. 
   All of the above
   

52- The only instrument of the following which is not used during access cavity preparation is:

1. 
   Endo-Z bur
   
2. 
   endodontic probe
   
3. 
   File size 15
   
4. 
   File size 40
   

53- Shape of the access cavity preparation of maxillary canine is:

a) Rhomboid

b) Oval

d)Rectangular

1. 
   5%
   
2. 
   9%
   

d)hardly any.

55-Percentage of maxillary first premolars having two roots:

a)20%

c)80%

56-Mandibular first premolars most often have:

a)one root with 2 root canals

b)one root with 1 root canal

c)2 roots with 2 root canals

d)2 roots with 3 root canals

b)Fractured two thirds of the crown.

c)Teeth with massive resorption

d)Teeth with sharp dilacerations.

1. 
   1 root canal , 1 orifice and 1 apical foramen .
   
2. 
   1 root canal , 1 orifice and 2 apical foramina .
   
3. 
   2 root canal , 2 orifice and 1 apical foramen .
   
4. 
   2 root canal , 2 orifice and 2 apical foramina.
   

59-Cervical root section of upper central incisor is:

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

60-The longest tooth in the arch is:

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

61-Mandibular incisors root canals are:

1. 
   Wider mesiodistally than labiolingually
   
2. 
   Wider labiolingually than mesiodistally
   
3. 
   Most frequently type III canal system
   
4. 
   None of the above
   

62-Which premolar has most frequently type I canal system

1. 
   Upper 4
   
2. 
   Lower 4
   
3. 
   Upper 5
   
4. 
   Lower 5
   

63-Cavity outline form in molars is located

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

64-Maxillary canine contains

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

65-The access outline form of upper premolars is

1. 
   round
   
2. 
   triangular
   
3. 
   oval
   
4. 
   rhomboid
   

66-Indications of endodontic therapy include:

a) Insufficient periodontal support

b) Non-strategic tooth

c) Vertical fracture

d) Non of the above

1. 
   Single root canal,single orifice,and single apical foramen
   
2. 
   Two root canals,two orifices,and two apical foramina
   
3. 
   Two canals,two orifices ,and one apical foramen
   
4. 
   Single root canal,single orifice ,and two apical foramina
   

68-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
   

1. 
   Maxillary central incisor
   
2. 
   Maxillary canine
   
3. 
   All of the above
   
4. 
   Non of the above
   

70-Cross section in the cervical third of maxillary canine is :

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

71-Maxillary first premolar root canal configuration is 70% :

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

72-Maxillary first molar may contain an extra canal called :

1. 
   MB2
   
2. 
   D2
   
3. 
   P2
   
4. 
   Non of the above
   

73-During access cavity preparation, straight line access is an objective to guarantee :

1. 
   Improved obturation
   
2. 
   Conservation of the tooth structure
   
3. 
   Unroofing of the pulp chamber
   
4. 
   b&c
   

74-Convenience form depends on :

1. 
   Size of the pulp chamber
   
2. 
   Shape of the pulp chamber
   
3. 
   Number of root canals
   
4. 
   Non of the above
   

75-Endo-Z bur is used in :

1. 
   Penetration
   
2. 
   Deroofing
   
3. 
   Flaring
   
4. 
   b&c
   

1. 
   Missed canal
   
2. 
   Gouging
   
3. 
   Perforation
   
4. 
   All of the above
   

77-The outline form of maxillary molars is:

1. 
   Oval
   
2. 
   Round
   
3. 
   Triangular
   
4. 
   Non of the above
   

78-Reference point should be :

1. 
   Easily visualized
   
2. 
   Changed during operation
   
3. 
   Usually the lowest point in the incisal edge of anteriors or cusp tip of posteriors
   
4. 
   a&c
   

79-The coronal pulp is formed of :

a) Pulp chamber and root canal

b) Pulp chamber and pulp horns

c) Pulp chamber and accessory canals

d) Root canal and accessory canals

80-The basic phases of endodontic therapy(Tripod) include all of the following except :

17. 
    Diagnostic
    
18. 
    Preparatory
    
19. 
    Irrigation of the cavity
    
20. 
    Obliteration
    

81-When shooting maxillary first premolar from mesial side, root (a) is considered:

1. 
   Palatal
   
2. 
   Buccal
   
3. 
   Mesial
   
4. 
   Distal
   

1. 
   Radiography
   
2. 
   Tactile sensation
   
3. 
   Electronic
   
4. 
   Common average tooth length
   

83-Difference between radiographic apex and actual foramen is approximately :

1. 
   1-3mm
   
2. 
   6mm
   
3. 
   4mm
   
4. 
   Non of the above
   

84- Diagnostic materials and devices include:

a- Vitality testing.

b- Tooth slooth.

C -Radiography.

d. Visual aids.

e. All of the above.
85- Instruments for access cavity preparation include:

a- Burs.

c -Barbed broach.

d. A & b.

e- None of the above.

86- Electric pulp testing is done to:

a- Determine whether pulp is normal or diseased.

b- Determine whether tooth is carious or not.

c- Differentiate between acute and chronic pulpits.

d- Differentiate between vital and non vital pulp.
87- Which of the following instruments is most likely to break during the root canal treatment :

a- Barbed broach.

b- K file.

c- K reamer.

d- Spreader.

88- All the following are exploring instruments except:

a -Endodontic explorer.

b- Smooth broach.

c- Apex locator.

d- Micro-opener.

a-Exploring canals orifices.

b-Enlarging root canals.

c-Extirpating pulp tissue

d-Determination of the tooth length

90-K File is:

a-Fabricated by twisting counter clock wise.

b-Square in cross section.

c-Used in filing and reaming action.

d-All of the above.

a-Used for reaming only.

b-Used for filing and reaming.

c-Has triangular cross section.

d-Is fabricated by twisting counter clock wise.
92- H File is:

a- Fabricated by machining (grinding).

b- Used for filing only.

c- None of the above.

d-A & b

93- Flexibility is increased by:

b- Decreasing the length.

c- Increasing the length.

D -Increasing the number of flutes per millimeter.

a - Nickel-titanium instruments.

b - Stainless steel instruments.

c- Carbon steel instruments.

d- A & c only.
95-According to ISO standardization the length of the cutting part is:

a - 0.02 mm.

b - 21 mm.

c – 0.32 mm.

d - 16 mm.

96-According to ISO standardization all the following is right except:

a- Taper is.02 mm/mm.

b- Tip design is 75+ or – 15 H degrees.

c- Linear increase in D1 by 0.05 mm from #15 to 60&0.1 mm from #.

d- D16=D1+ 0.21 mm.

a-The increase in diameter from D1 to D16 is 0.15 mm.

b-The length from D1 to D16 is 15 mm.

c- Diameter at D1=0.15 mm.

d- The length from the working tip to the file handle is 15 mm.
98-Hybrid instruments means presence of modifications include:

a- The depth and the angle of the blades.

b-The material: carbon steel, St St, Ni Ti.

c- Method of manufacture.

d- Standardization.

e- All of the above.

99-Spreaders are used for:

a- Vertical condensation.

b- Lateral condensation.

c-Pulp extirpation.

d-Root canal preparation.

100-Satisfactory sterilization of endodontic instruments may be achieved by:

a- Autoclave with steam under pressure at 121 c for 20 minutes.

b- Dry heat at 160 c for one to one and half hours.

c-Both of the above are correct.

d-None of the above are correct.

101-In endodontic, sterilization methods used are:

a- Dry heat and autoclave.

b- Hot bead sterilizer and chemical sterilization.

c- Both A and B.

d-None of the above.
102-The rubber dam is used mainly to:

a-Prevent irrigating solution from entering the oral cavity.

b-Prevent salivary contamination of the root canal system.

c- Prevent the patient from aspirating files.

d-All of the above.
103-Headstrom-type files are more prone to separation because of:

a-The decreased cross-sectional diameter of equivalent-sized instruments.

b-Their design does not facilitate reaming.

c-A and B.

d-None of the above.
104-The main objectives of cleaning and shaping are:

a- Cleaning the root canal system from organic remnant.

b- Cleaning root canal system from inorganic irritants.

c- Shaping the root canal system to receive a three dimensional hermetic seal.

d-All of the above.
105-The root canal should be enlarged enough to:

a-Permit adequate debridement.

b-Manipulate and control of obturating materials.

c-Both A and B.

d-None of the above.
106-The first file used in apical preparation after straight line access is:

a- The initial file.

b-The master apical file.

c-The final file.

d-None of the above.

107-Biomechanical preparation of root canal is done :

a-In a wet environment with irrigants flooded in the canal.

b-In dry environment with no irrigants.

c-In dry or wet environment depending on the operators choice.

d-All of the above.

a-Creation of ledge.

b Debridement of root canal.

c-perforation of apical foramen.

d-None of the above.
109-Motion used in apical preparation is.

a-Reaming.

b-Filing.

c-Watch winding motion.

d-Balanced forced.
110-Motion used in coronal flaring:

a-Reaming.

b-Filing.

c-Watch winding.

d-Balanced force.
111-The instrument used in flaring is:

a- K reamer.

b- plugger

c- H file.

d- None of the above.
112- Flaring means:

a- Apical third preparation.

b- Apical stop creation.

c- Funneling the coronal two thirds.

d- Funneling the apical third.
113-Obturation techniques include the following:

1. 
   Cold lateral compaction.
   
2. 
   Warm vertical condensation.
   
3. 
   Step back technique.
   
4. 
   a & b.
   

1. 
   Continuously tapered funnel shaped with apical matrix in sound dentin 0.5-1 mm short of radiographic apex.
   
2. 
   Cylindrical with apical matrix in sound dentin 0.5-1mm short of radiographic apex.
   
3. 
   Continuously tapered funnel shaped flushing with the radiographic apex.
   
4. 
   Continuously tapered with open apex 0.5-1mm short of the radiographic apex.
   

115-These instruments and materials are used in obturation except :

1. 
   Lentulo spiral .
   
2. 
   Spreaders.
   
3. 
   Tooth slooth.
   
4. 
   Heat carrier
   

116-Master cone should fulfill the following except:

1. 
   reach full working length.
   
2. 
   Fit tightly in canal from orifice to apex.
   
3. 
   Resist removal (tug back).
   
4. 
   Resist moving beyond the apex.
   

117-If the master cone selected is tested and found to be passing beyond the apex by 2mm ,we can solve this problem by:

1. 
   Withdrawal of the cone 2 mm.
   
2. 
   Use larger cone not necessarily reaching the working length.
   
3. 
   Cut off 1-2 mm from the tip of the cone and remark the working length.
   
4. 
   None of the above.
   

118-If the selected master cone is tested and found to be shorter than the working length,this may be due to:

1. 
   Debris packed in the apical portion.
   
2. 
   Presence of a ledge shorter than the working length.
   
3. 
   The working length was not measured from the selected reference point.
   
4. 
   All of the above.
   

119-Radiograph shows the master cone extended beyond the working length, but the visual and tactile tests were correct. what is the cause of the problem?

1. 
   Gatta percha is small.
   
2. 
   Spreader is large.
   
3. 
   Apical stop is violated.
   
4. 
   Incorrect working length determination.
   

a) Reach full working length when the canal is empty.

b) Reach 2mm short along side of the master cone.

c) Should be smaller in size than #25.

d) Spreader applies lateral force on the gutta percha.
121--The requirements of the ideal root canal sealer are :

1. 
   easily manipulated .
   

c)Should be of thick consistency upon mixing.

d)a & b .

e)b & c .

1. 
   Extend to prepared length .
   
2. 
   Have uniform density from coronal to apical aspect .
   
3. 
   Have close adabtation to canal walls.
   
4. 
   All of the above.
   

123- Master cone selection is based on :

1. 
   Initial file size .
   
2. 
   Master apical file size .
   
3. 
   Spreader size .
   
4. 
   Accessory cone size.
   

124-Ideal master cone should be :

1. 
   Fit only in the apical 1-2mm of the canal.
   
2. 
   Binding along the canal.
   
3. 
   One size larger than the initial file .
   
4. 
   None of the above .
   

125- Sealer may placed by any of the following except:

1. 
   Lentulo spiral
   
2. 
   Condenser
   
3. 
   Master cone
   
4. 
   Paper point.
   

126-The proper root canal sealer consistency may be verified by :

1. 
   String test.
   
2. 
   Rubber dam test.
   
3. 
   Test drop.
   
4. 
   a & c .
   

1. 
   Same size as the master cone .
   
2. 
   One size larger than the selected spreader .
   
3. 
   Same size of the master apical file .
   
4. 
   One size smaller than the selected spreader.
   

128-The following materials are can be used as irrigants except :

1. 
   Chlorhexidin
   
2. 
   H2O2
   
3. 
   NaOCl
   
4. 
   Zinc Oxide Eugenol
   

129-The apical 1-2 mm of the canal is enlarged by :

1. 
   filing motion
   
2. 
   Reaming motion
   
3. 
   In and out motion
   
4. 
   Watch winding motion
   

130- underfilling may be due to

a) over instrumentation beyond the apical constriction.

b) lack of canal patency and insufficient taper

c) use of exssecive amount of force.

d) a & c
131- the following are needed for lateral compaction method except:

a) sealer

b) gutta-percha points

c) spreaders

d) pluggers

a-Enlarging the apical foramen.

b-Incomplete preparation of the root canal.

c-Ledging the canal.

d- Traumatizing the apical tissue.

133- The fracture of root canal instrument may be caused by:

a- Incorrect access to the root canal.

b- Too vigorous instrumentation.

c- Using a too large sized reamer.

d- Using twisted or rusted or damaged instruments.

e- All of the above are correct.
134- Sodium hypochlorite solution is good for irrigation of root canal because:

a- It acts as bactericidal.

b- It acts as solvent for pulp tissue and debris.

c- It acts as lubricant for instruments within canals. d - It bleaches teeth.

e- All of the above are correct.
135- Obturation of canal system aims to:

a- Three dimensionally seal the root canal system (laterally, apical and cervical).

b- Two dimensionally seal the root canal system apical and cervical.

c- Apical seal the root canal system.

d- None of the above.
136- Prepared canal that will be obturated with lateral cold compaction should be:

a- severely curved canal.

b- Internally resorped canal.

c- Continuously tapered funnel shape with an apical matrix.

d. All of the above.
137- Cold lateral compaction technique include the following steps except:

a- Master cone and spreader selection.

b- Mixing of sealer and sealer placement.

c- Master cone placement, compaction and placement of accessory cones.

d- Flaring of the coronal two third.

e- Removing excess gutta-percha and management of pulp chamber.

a-Reach the full working length.

b-Fit only in the apical 1-2 mm of the canal.

c-Slightly resist removal on withdrawal from the canal space (tug back action).

d.Resist moving beyond the apex.

e- All of the above are correct.

139--The master gutta-percha cone must fill the canal tightly in the:

a-Apical third.

b-Middle third.

c-Occlusal third.

d-None of the above.
140- Ideal root canal filling material should be:

a-Easily introduced into the canal.

b-Semisolid.

c-Dimensionally stable.

d-All of the above.
141- The disadvantage of gutta-percha used as filling material is:

a- Poor biocompatibility.

b-Difficulty in preparing post space.

c.Lack of rigidity in smaller size.

d.Solubility in organic solvent.
142--The term "tug back" is related to:

a-Condensation of the gutta-percha.

b-Fit of the master cone in the apical third.

c-Length of the cone.

d-Tensile strength of gutta-percha.

e-Width of the cone.

a-Beyond the radiographic apex.

b-The dentinocemental junction.

c-To the radiographic apex.

d-None of the above.
Good Luck

1- b 2- c 3- a 4- a

5- c 6- b 7- a 8- d

9-b 10-d 11-c 12-d

13-c 14-b 15-b 16-d

17-b 18-b 19-c 20-b

21-d 22-b 23-c 24- a

25-b 26-a 27-c 28 -a

29-c 30-c 31-a 32-c

33-d 34-b 36-d 36-b

37-a 38-d 39-c 40-b

41-b 42-d 43-c 44-a

45-c 46-c 47-a 48-a

49-b 50-b 51-e 52-d

53-b 54-d 55-c 56-b

57-b 58-b 59-c 60-d

61-b 62-d 63-a 64-a

65-c 66-d 67-b 68-a

69-c 70-a 71-c 72-a

73-a 74-d 75-d 76-a

77-c 78-a 79-b 80-c

81-a 82-d 83-a 84-e

85-d 86-d 87-a 88-c

89-c 90-d 91-b 92-d

93-c 94-a 95-d 96-d

97-c 98-e 99-b 100-c

101-c 102-d 103-c 104-d

105-c 106-a 107-a 108-b

109-a 110-b 111-c 112-c

113-d 114-a 115-c 116-b

117-c 118-d 119-d 120-c

121-d 122-d 123-b 124-a

125-b 126-a 127-d 128-d

129-b 130-b 131-d 132-c

133-e 134-e 135-a 136-c

137-d 138-e 139-a 140-d