Impression: (CH 2)

1-Which of the following impression materials is thermoplastic?

A. Impression compound b. Zinc oxide and eugenol
C. Plaster of Paris d. None of the above
2-Which of the following impressions can be electroplated?
A. Polyether B. Impression compound
C. Agar-Agar D. Alginate
3-Which of the following impression produces the highest elastic recovery
A. Addition silicon B. Poly-sulphide
C. Polyether D. Alginate

4-Surfactant is added to :
A. Addition silicone. B. Agar-Agar.
C. Plaster of Paris impression. D. Alginate.
5-Rubber bases can be disinfected by various antimicrobial solutions for long periods without dimensional changes
except:
A. Addition silicon. B. Poly-sulphide.
C. Polyether. D. Impression compound.

6- Which of the following materials is the stiffest?

A. Condensation silicon B. Impression compound
C. Alginate D. Polyether
7. ---------inelastic impression material can be used in edentulous patients with high degree of accuracy.
A. Addition silicone. B. Impression compound
C. Plaster of Paris impression D. Alginate.
8. -------is Inelastic impression used as primary impression for edentulous patient :
A. Impression compound B. ZnO/E
C. Plaster of Paris D. Alginate
9. Impression can be classified according to manner of setting into:
A. Inelastic and elastic impression B. Physical and chemical set
C. Primary and secondary D. Dentulous and edentulous
10. Flexibility of impression means:
A. Ease of removal from undercut
B. Recover to original shape when removed from undercut
C. Permanent deformed when removed from under cut
D. Fractured when removed from undercut

11. Which of the following impression materials is used as primary impression:

A. Impression compound B. Zinc oxide and eugenol
C. Plaster of Paris D. None of the above
12. Which of the following impressions can not be electroplated?
A. Polyether B. Impression compound
C. Agar-Agar D. Alginate E. A&C&D
13. Loss of water by evaporation from the surface of hydrocolloids gel is called :
A. ImbibitionB. MemoryC. HysteresisD. Syneresis

14. For better accuracy , an impression tray should:

A. Adhere to the impression
B. Allow an impression of an even thickness
C. Be rigid
D. All of the above
15. Alginate impression material :
A. Can be electroplated
B. have higher tear strength
C. Is an irreversible hydrocolloids impression material
D. Used as a secondary impression
16. A complete denture patient having difficulty with retention of a maxillary denture because :
A. Of its high strength
B. Of its high density
C. Of its high coefficient of thermal expansion and contraction
D. Of its high modulus of elasticity
17. Alginate impression should be removed by sharp snap removal from the patient mouth to :
A. Increase permanent deformation
B. Increase tear strength
C. Decrease permanent deformation D. B & C E. A & C
18. The best method to store an alginate impression is in :
A. water for maximum one hour
B. air for maximum one hour
C. a damp towel for maximum one hour
D. 100 % relative humidity up to 24 hours
19. The impression material with the highest tear strength is :
A. Addition silicon rubber B. Polyether rubber
C. Polysulfide rubber D. Agar-agar hydrocolloid
20. The rubber base impression that is most easy to remove after setting is :
A. Addition silicon rubber
B. Polyether rubber
C. Polysulfide rubber D. Condensation silicon
21. Which of the following impression water is essential for its setting :
A. Impression compound
B. Zinc oxide eugrnol
C. Polyether
D. None of the above
22. Electroplated dies can be made from the following impression except :
A. Polyether
B. Polysulfide
C. Addition silicon
D. Condensation silicon
23. The most flexible impression material is :
A. Polysulfide rubber
B. Condensation silicon rubber
C. Addition silicon rubber
D. Polyether rubber
24. Rubber base impression set by :
A. Gelation B. Chelation
C. Polymerization reaction D. Acid – base reaction

25. Sulfur containing gloves should be avoided during mixing ……….. impression material as it affects its setting reaction:
A. Addition silicon B. Polysulfide
C. Polyether D. Impression compound
26. Material used for border molding is:
A. Addition silicon B. polysulfide
C. polyether D. Impression compound (green stick)
27. ……… represents the most none acceptable elastic impression material by the patient:
A. Addition silicon B. Polysulfide
C. Polyether D. Impression compound
28. Which of the following statements is true regarding the impression compound:
A. Should have a very low strength to be broken away easily after casting
B. Impression compound has low thermal conductivity
C. Impression compound can be used as secondary impression material
D. Impression compound is highly accurate for completely edentulous patient
E. All of the above
29. All of the following statements is true except:
A. Electroplating is not indicated in hydrocolloid impression
B. Impression compound and agar set by reduction in temperature
C. No separating medium is recommended during pouring of elastic impression
D. All elastic impressions are self adhesive to the tray

30. Plaster impression material:

A. Dehydrates the oral tissues
B. cannot be reassembled
C. Is difficult in manipulation
D. All of above
31. Polyether should be used in thick section as result of low:
A. Flexibility
B. Tear strength
C. Permanent deformation
D. Flow
E. None of the above
32. Elastic impression materials should be flexible to:
A. Record undercut areas
B. Be compatible with gypsum product
C. Be easily removed from the patient mouth
D. Be compatible with tray materials
E. Record fine details

33. …………… is a factor affecting accuracy of an impression material:

A. Malleability B. Ductility C. Plasticity D. Fluidity
34. Which of the following impression materials need separating medium before pouring the gypsum products:
A. Agar- agar B. Polyether C. Plaster of Paris D. Impression compound
35. Agar-agar can be used multiple times for the same patient as:
A. It sets by physical reaction B. It sets by chemical reaction
C. It has an elastic property D. It is a hydrophilic material
E. All of the above
36. …………is essential for the reaction Zinc oxide eugrnol impression material:
A. Water
B. Gum rosin
C. Oil of cloves
D. Magnesium chloride E. All of the above

37. The hydrophilic nature of polyether allows for the following except:
A. Proper reproduction of fine details
B. Disinfection by spraying
C. Proper accuracy in wetting
D. Electroplating
38. The following impression materials need perforated tray except:
A. Light body addition silicon B. Putty type condensation silicon
C. Putty type addition silicon D. Alginate impression material
39. The tray used with alginate impression is:
A. Ready-made B. Specially made C. None of them
40. The tray made from with alginate impression is:
A. Metal B. Plastic C. Acrylic resin
41. The tray with alginate impression is:
A. Perforated B. None perforated C. None of them
42. Alginate supplied in form of :
A. Two paste B. Powder and water liquid
43. Alginate was mixed by using:
A. Glass slab and spatula B. Rubber bowel and spatula
44. Thickness of alginate impression in tray:
A. 2-3mm B. 4-6mm C. 3-4mm
45. Alginate impression set by:
A. Chemically B. Physical

46. Increase powder/liquid ratio in alginate:

A. Increased setting time (prolonged)
B. Not affect setting time
C. Decreased setting time (fast setting)

47. Vigorous, rapid mixing of alginate will lead to:

A. Increased setting time
B. Not affect setting time
C. Decreased setting time (fast setting)
48. The obtained gypsum for alginate impression should be:
A. Immediately B. After one hour. C. After 24 hours
49. For proper storage of alginate:
A. Wrapped by wet towel and inserted in plastic bag
B. Immersed in rubber bowel containing water
C. Air bench stored
50. The tray used with agar-agar impression is:
A. Ready-made B. Specially made C. Specially desinged
51. The tray made from with agar-agar impression is:
A. Metal B. Shellac base C. Acrylic resin
52. Agar-agar supplied in form of :
A. Two paste
B. Powder and water liquid
C. Jar and two pasts
D. Jell in sealed container
53. Agar-agar was softened by:
A. Flame B. Water bath C. Special softening equipment
54. Agar-agar impression set by:
A. Gellation B. Chelation C. Polymerization reaction
55. The most common use of agar-agar impression is:
A. Primary impression B. Secondary impression C. Cast duplications
56. The tray used with rubber base medium flow is:
A. Ready-made B. Specially made C. None of them
57. The tray made from with rubber base medium flow is:
A. Metal B. Shellac base C. Acrylic resin
58. The tray with rubber base medium flow is:
A. Perforated B. None perforated C. None of them

59. Rubber base medium flow supplied in form of :

A. Two paste B. Powder and water liquid C Jar and two pasts
60. Rubber base medium flow was mixed by using:
A. Glass slab and spatula B. Rubber bowel and spatula
61. Thickness of all rubber base impression in tray except polyether is:
A. 2-3mm B. 4-6mm C. 3-4mm
62. Rubber base impression set by:
A. Chelation B. Gellation C. Polymerization reaction
63. Try should be painted by adhesive liquid before rubber base impressions loading due to:
A. Hydrophilic nature of rubber base impression
B. Hydrophobic nature of rubber base impression
C. Low viscosity of rubber base impression
64. Surfactant applied above silicon impression before gypsum pouring to:
A. Reduce contact angle between gypsum products and hydrophobic impression
B. Decrease surface air bubbles of model (Rough model surface)
C. All of the above
65. The tray used with rubber base heavy and light flow is:
A. Ready-made B. Specially made C. None of them

66. The tray made from with rubber base heavy and light flow is:
A. Metal B. Shellac base C. Acrylic resin
67. The tray with rubber base heavy and light flow is:
A. Perforated B. None perforated C. None of them
68. Rubber base heavy and light flow supplied in form of :
A. Two paste B. Powder and water liquid C Jar and two pasts
69. Heavy or putty consistency impression considers:
A. Secondary impression B. Primary impression
C. Tray for light consistency impression
70. Wash technique impression considers:
A. Primary impression B. Secondary impression
71. Gypsum model for Rubber base heavy and light flow is:
A. Study cast B. Master Cast C. Primary cast
72. All rubber base impression can be electroplated except polyether due to:
A. It is hydrophobicity B. It is hydrophilicity C. It is high flow
73. Type one gypsum product is used as:
A. Die material
B. Impression material C. Model material
D. Investment material E. All of the above
74. Perforated tray is used with:
A. Putty consistency condensation silicone
B. Zinc oxide and eugenol impression material
C. Plaster impression material
D. Impression compound
E. None of the above
75. An assistant was in a hurry, and did not pour the alginate impression material till the next day what will happen to the
impression?
A. Deformation B. Imbibition C. Loss of accuracy D. Synersis

76. …………. Represents the hydrophilic elastic impression material:

A. Zinc oxide and eugenol impression material
B. Polysulfide impression material
C. Plaster of paris impression material
D. Polyether impression material
 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
A B A A C D C A B A A E D D C B D D C C

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
B A A C A D B B D A A C D C A A D A A A

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
A B B B A C C A A C A D C A C B C B A A

61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
C C B C A A A A C B B B B A D D
- MCQ:

1. The presence of excess mercury in the amalgam mix:

A. Decreases the strength B. Increases the creep.

C. Increases the setting expansion D. All of the above E.A&B

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2. High-copper amalgam is characterized by elimination of:

A. Ag3 Sn (γ phase) B. Ag2 Hg3 (γ1 phase)

C. Sn8 Hg (γ2 phase) D. Cu6Sn5 (η phase)

3. Homogenization of amalgam ingot results in:

A. Decrease in the corrosion resistance

B. Decrease in the mechanical properties of amalgam

C. Even distribution of Ag and Sn in the Ag3Sn crystals

4. The weakest and most corrodible phase of dental amalgam is:

A. Ag3 Sn (γ phase) B. Ag2 Hg3 (γ1 phase)

C. Sn8 Hg (γ2 phase) D. Cu6Sn5 (η phase)

5. Dental amalgam is bonded to tooth structure via:

A. Chemical bonding B. Micro-mechanical bonding

C. Physical bonding D. Macro-mechanical bonding

6. ………… is added to dental amalgam alloy to control oxidation:

A. Zinc B. Tin C. Copper D. Silver

7. All of the following elements of dental amalgam decrease the creep except:

A. Silver B. Copper C. Tin D. Zinc

8. The ingredient that increases the corrosion resistance of dental amalgam is:

A. Hg B. Sn C. Zn D. Ag

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9. Silver is added to amalgam powder to increase:

A. Creep B. Corrosion susceptibility C. delayed expansion D. strength

10. The phase having the lowest strength in set amalgam is:

A. Gamma one B. Eutectic silver copper C. Gamma phase D. Gamma two

11. Dental amalgam undergoes creep because of its:

A. Fluidity B. Viscosity C. Elasticity D. Viscoelasticity

12. Mercury needed for lath cut alloy when compared to spherical one:

A. Larger amount B. The same amount C. Lesser amount D. Dull appearance

13. Mercury needed for zinc free lath cut alloy when compared to zinc containing spherical one:

A. Larger amount B. The same amount C. Lesser amount D. Dull appearance

14. Immediate dimensional in amalgam results from:

A. Moisture contamination during trituration

B. Moisture contamination after hardening

C. Crystal impingement during growth D. after 5 days of amalgamation

15. The role of copper in dental amalgam:

A. Acts as scavenger B. Increases creep

C. Increases strength D. Causes immediate dimensional changes

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16. Silver is added to amalgam powder to increase:

A. Creep B. Corrosion susceptibility

C. delayed expansion D. Corrosion resistance

17. The admixed high copper amalgam contains:

A. Copper more than 6% B. No eutectic silver copper alloy

C. Zinc metal more than high copper amalgam D. Tin less than 6%

18. The presence of excess mercury in the amalgam mix:

A. Decreases the strength B. Decreases creep.

C. Decreases setting expansion D. Increases corrosion resistance

19. Homogenization heat treatment of amalgam powder is important for:

A. Elimination of remaining zinc B. Elimination of coring (heterogonous)

C. Elimination of gamma two D. Elimination of coarser powder particles

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

D C C C D A C D D D D A A C C D A A B

MCQ:

1. The greatest amount of polymerization shrinkage occurs in:

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A. Fine particle- resin composite B. Micro-filled composite

C. Macro-filled resin composite D. Hybrid resin composite.

2. Diluent is incorporated in the resin composite:

A. To reduce the viscosity of the material.

B. To allow the incorporation of sufficient amount of fillers.

C. To facilitate the clinical manipulation of the material. D. All of the above.

3. In composite restoration, the ……….. decreases polymerization shrinkage and coefficient thermal

expansion:

A. Matrix B. Filler particles C. Silane coupling agent D. Pigments

4. Compared to posterior composite, the micro-filled composites have:

A. High mechanical properties B. High polymerization shrinkage

C. High coefficient of thermal expansion D. B&C

5. The function of silane coupling agent in a dental composite composition is:

A. Stress transfer from the matrix to filler B. Prevention of early loss of fillers

C. Bonding of filler to matrix D. All of the above

6. The organic matrix of recent dental restorative resin composites is composed of:

A. UDMA and/or Bis-GMA B. PMMA polymer

C. Polystyrene polymer D. Silicon rubber

7. The main possible cause of a composite filling with stained margin is:

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A. Low wear resistance B. High polymerization shrinkage C. Water sorption

D. Low strength

8. For increasing shelf life (storage time) of photo-initiated (light) composites, …………. must be

present:

A. Hydroquinone B. Camphorquinone and tertiary amine

C. Triethylene glycol dimethacrylate D. Silane coupling agent

9. Which of the following is higher for fine particle composites than for micro-filled composites?

A. Polymerization shrinkage B. Thermal expansion

C. Water sorption D. Mechanical properties

10. Which of the following fillers may provide radiopaque composites?

A. Quartz B. Lithium aluminum silicate C. Colloidal silica D. Barium glass

11. Presence of multiple voids in an anterior tooth colored restorations; the material appears more

opaque due to ………. of light:

A. Dispersion B. Distortion C. Scattering D. Fluorescing

12. Dental composite filling material have:

A. Polymer matrix + Glass filler B. Polymer matrix + Metallic filler

C. Polymer filler + Glass matrix D. Glass matrix + Metallic filler

13. The role of hydroquinone in dental composite is to decrease:

A. Wear. B. Radiolucency. C. Water sorption. D. None of answer.

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14. The residual monomer in composite resin make the composite:

A. Irritant B. Harder C. Stronger D. More esthetics

15.The visible wave length used for light activated composite resin is:

A. Yellow range B. Green range C. Blue range D. Red range

16. Light cured composite have more color stability than cold cured one due to difference in:

A. Type of filler B. Type of matrix C. Type of coupling agent

D. Type of activator

17. A hybrid dental composite is a mixture of:

A. BIS – GMA and Bowen's resin B. BIS – GMA and filler

C. BIS – GMA and coupling agent D. Fine-filled and micro-fine

18. For a chemical bond to be achieved between filler and resin matrix in composite, filler particles

are usually treated with:

A. Deoxidizing agent B. Wetting agent C. Coupling agent D. Etching agent

19. Dimensional instability and consequently microleakage of dental resins are usually due to:

A. High coefficient of thermal expansion B. Polymerization shrinkage

C. Water sorption D. All of answers

20. Difference in hardness between resin matrix and filler creates a problem in:

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A. Adapting the resin against the cavity walls B. Finishing and polishing

C. Removal of filling after setting D. Diagnosing caries recurrence

21. A cavity liner placed under the composite resin to act as:

A. Thermal insulator B. Chemical insulator C. Bonding agent

22. Chemically activated composites are:

A. Two paste systems B. Single paste system

23. Material is recommended as sub base under composite filling is:

A. ZOE B. Ca (OH) 2 C. Cavity varnish

24. The most important contribution of filler in a resin matrix is to improve:

A. Polishability B. Water sorption C. Modulus of elasticity

25. A composite can be bonded to the enamel by use of acid etch technique. The effect of acid is to:

A. Clean the surface of the enamel B. Cause rough surface

C. Remove the organic matrix D. Both A & B

26. All except one are effects of fillers on composite properties:

A. Improve mechanical properties B. Minimize thermal expansion

C. Minimize polymerization shrinkage D. Maximize water sorption

27. The more the filler you add to the composite resin:

A. The more polymerization shrinkage you get

B. The more favorable tensile strength you get

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C. The more favorable bonding to tooth you gets

28. The filler particle size of fine filled composite is:

A. 0.005 – 0.01 µm B. 0.5 – 3 µm C. 2 – 5 µm

29. The most commonly used photoinitiator is:

A. Zenon B. Camphoroquinone C. Hydroquinone

30. Light cured composite is:

A. More color stable than dark cure one B. Less color stable than dark cure one

31. Acid etching technique:

A. Increases composite / tooth tissues chemical bonding

B. Increases composite / tooth tissues mechanical bonding

32- Etching of dentin will lead to:

A- Increase surface energy of dentin B- Remove smear layer

C- Decrease organic content D- All of the above

33- Factors that present difficulty in adhesion with tooth structure is:

A- Presence of smear layer B- Homogenous composition

C- Clean length or tooth or surface D- All of the above

34- A layer of resin that infiltrated dentin known as:

A- Hybrid layer B- Smear layer C- All of the above

35- Acid etching of tooth surface lead to:

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A-increase surface energy of enamel B-increase surface energy of dentin

C-increase surface tension of enamel D-all of the above

36. What type of enamel / restoration bond is created when an acid-etch technique is used ?

A) Chemical (ionic) B) Chemical (covalent)

C) Micromechanical D) All of the above

37. What is 'conditioner'?

A) Acid B) Dentin priming agent C) Dentin bonding agent D) Alcohol

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

B D B D D A B A D D C A D A C D D C B B

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

B A B C D D B B B A B B A A A C A

- Cements: (CH 3)

- MCQ:

1. The purpose of adding epoxy benzoic acid to zinc oxide and eugenol is:

A. To improve the strength B. To improve ease of manipulation

C. To improve bonding to the tooth structure D. To improve esthetics

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2. Which of the following statement about glass ionomer cement is not true:

A. the cement liquid is a polycarboxylate copolymer in water

B. the cement must be protected from exposure to water during setting

C. the cement powder is an aluminosilicate glass

D. the cement bond mechanically to tooth structure

3. Zinc oxide and eugenol cement has an inhibiting effect on :

A. all the answer are correct B. setting reaction of glass ionomer

C. setting reaction of zinc phosphate cement

D. amalgamation reaction of dental amalgam

E. polymerization reaction of dental composite resin

4. Zinc phosphate cement is the best choice for permanent cementation of a restoration because :

A. it is the highly soluble cement

B. it has the lowest bond strength of all cements

C. it has the least film thickness D. it has the lowest strength among all cements

E. it is translucent cement

5. Zinc polycarboxylate cement is less irritant than zinc phosphate cement as the former (zinc

polycarboxylate) :

A. has less PH B. all answer are correct

C. is of higher molecular weight D. reaches neutrality in 48 hours

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6. Which of the following cement bond to tooth structure has an anticariogenic effect , has a degree of

translucency and does not irritate to the pulp:

A. resin cement B. zinc polycarboxylate cement

C. glass ionomer cement D. silicate cement

7. Which of the following cement is\are opaque:

A. zinc polycarboxylate B. zinc oxide and eugenol cement

C. zinc phosphate cement D. all of the above

8. the glass ionomer cement margin are coated with a coating agent to :

A. lubricate the tooth B. enhance bonding

C. protect against light D. protect against moisture

9. the lowest film thickness of these cement is :

A. zinc oxide and eugenol B. zinc phosphate

C. zinc polycarboxylate D. reinforced zinc oxide \ eugenol

10. the purpose of adding ethoxybenzoic acid to zinc oxide eugenol cement is to :

A. improve the compressive strength of the cement

B. render the cement light curable

C. improve the ease manipulation of the cement

D. improve the tensile strength of the cement

11. which of the following describe cermet cement :

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A. cermet cement is glass ionomer cement with porcelain ceramics filler

B. cermet cement is glass ionomer cement with silver amalgam alloy particles in it

C. cermet cement is a mixture of glass ionomer and resin cements

D. cermet cement is a self cure composite resin

12. regarding zinc phosphate cement :

A. powder and liquid are mixed in cold glass slab

B. powder and liquid are mixed in hot glass slab

C. zinc phosphate cements have endothermic reactions

D. retention is via chemical bond

13. calcium hydroxide cements :

A. used for direct and indirect pulp capping

B. interfere with the polymerization of restorative material

C. have acidic PH D. all of the above

14. Adhesive resin cements are also known as phosphonate cements because :

A. have phosphonate end that reacts with calcium of the tooth

B. Are similar in properties to zinc phosphate cements

C. Are similar in reaction to zinc phosphate cements

D. all of the answers are correct

15. Concerning calcium hydroxide cement, which of the following statement is true:

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A. it is highly alkaline and soluble material

B. it is used as base under amalgam restorations

C. it is used as a pulp capping agent due to its high acidity

D. it should be applied to the wall of the cavity

16. in a patient with a high caries tendency, the use of ………. is recommended:

A. amalgam B. porcelain C. composite D. glass ionomer

17. unmodified zinc oxide and eugenol cement should not be used under amalgam restorations as it

has :

A. has obtunding effect B. low film thickness C. low mechanical properties

D. poor optical properties

18. the following cements are not irritant to the pulp except :

A. conventional glass ionomer cement B. zinc phosphate cement

C. hybrid ionomer cement D. zinc poly carboxylate cement

19. Among to the following cements, ……… has the highest initial sensitivity to moisture :

A. conventional glass ionomer cement B. zinc polycarboxylate

C. hybrid ionomer cement D. resin cement

20. film thickness of dental cements is affected by :

A. temperature B. liquid\powder ratio

C. mixing time and rate D. all of the above

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21. Which of the following cements has the highest modulus of elasticity:

A. zinc polycarboxylate cement B. zinc oxide and eugenol cement

C. zinc phosphate cement D. calcium hydroxide cement

22. water settable cements include :

A. ZnO\E and Zn phosphate cements

B. Zn phosphate and Zn polycarboxylate cements

C. Zn phosphate and silicate cements

D. Zn polycarboxylate and glass ionomer cements

23. Resin cements are characterized by :

A. obtunding B. transparent C. insoluble D. anticariogenic

24. The properties of conventional ZnO\E cements make it the choice to be used as:

A. temporary filling material B. cement base under amalgam

C. cement base under composite D. permanent luting cement

25. According to zinc phosphate cement :

A. it has the least film thickness B. it has the least modulus of elasticity

C. chemical bonding to tooth structure

D. anticariogenicity due to fluoride release

26. Among the following cements,…………. is the best choice as a pulp capping material:

A. Calcium hydroxide B. Silicate cement

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C. Zinc phosphate cement D. Resin cement

27. The main advantage of zinc phosphate cement is:

A. It has the least film thickness compared to other cements

B. It has the least modulus of elasticity compared to other cements

C. Chemical bonding to tooth structure

D. Anticariogenicity due to fluoride release

28. The main disadvantage of zinc phosphate cement is:

A. Low strength B. Low rigidity C. High initial acidity D. All of the above

29. Which of the following cements could be used for temporary cementation?

A. Zinc phosphate B. Zinc polycarboxylate

C. Glass ionomer cement D. None of the above

30. Zinc phosphate cement has:

A. Mild effect on pulp B. Sedative effect upon pulp

C. Higher compressive strength D. Higher tensile strength

31. The cement adhering chemically to tooth structure is:

A. Zinc phosphate B. Zinc oxide and eugenol C. Composite cement

D. Zinc polycarboxylate cement

32. Polycarboxylate cement is biocompatible to pulp due to:

A. High molecular weight B. Slow PH rise C. Higher intrinsic toxicity

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33. The cement that hardens by chelating process is:

A. Zinc oxide and eugenol

B. Modified zinc oxide and eugenol /ethoxybenzoic acid

C. Resin modified zinc oxide and eugenol D. All of answers

34. Zinc oxide and eugenol cement is better than zinc phosphate one in:

A. Biocompatibility B. bonding with tooth C. Compressive strength

D. All answers

35. Zinc polycarboxylate cement and glass ionomer cements are similar in:

A. Their liquid B. Their powder

36. Glass ionomer cement makes chemical bond with porcelain:

A. True B. false

37. Glass ionomer cement is anticariogenic because it contains:

A. Aluminum polycarboxylate matrix B. Calcium polycarboxylate matrix

C. Unreacted alumino silicate powder containing fluorine

38. Cavity varnish is used under glass ionomer cement to stimulate reparative dentin:

A. True B. false

39. Cavity varnishes are:

A. Calcium hydroxide in a resin base B. Used to insulate pulp thermally

C. Used beneath composite resin to insulate the pulp against chemical irritation

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D. Synthetic resin dissolved in acetone

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

A D E C C C D D B A B A A A A D C B A B

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

C D C A A A A C D C D A D A A B C B D

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