operative dentistry

1. Adhesion & Composite

2. Choose the most suitable answer

3. 1- the most common acid used for etching teeth is:
a- hydrochloric acid
b- Phosphoric acid
c- Sulfuric acid
d- Acetic acid

4. 2- Retention form for resin composite restorations is
achieved through:
a- chemical bond with the tooth
b- Adhesion to enamel and dentin
c- Mechanical undercuts.
d- all of the above

5. 3- Metal instruments are contraindicated to be used with
resin composite restoratives because:
a- the metal is abraded by the filler and discolors
the restoration
b- The monomer reacts with the metal and forms corrosion
products which affects the final shade
c- The polymer reacts with the metal to affect the shade
d- The metal inhibits polymerization.

6. 4- Adhesive cavity design for class I should be
characterized by:
a- conservative outline
b- Diverging buccal and lingual walls
c- Rounded pulpal floor
d- Occlusal lock retention
e- a and c
f- a and d
g- all of the above.

7. 5- The advantages of visible light curing resin composite
system are:
a- adequate degree of conversion
b- Possibility of air inclusion
c- Superior color stability
d- Controlled shrinkage
e- c and d
f- all of the above

8. 6- What is the term used for polyacid modified resin
composite?
a- hybrid ionomer
b- Compomer
c- Hybrid composite
d- Resin modified glass ionomer
e- Microfilled composite.

9. 7- The primary factor in developing the outline form for
a composite resin restoration on the proximal surface of
an anterior tooth is:
a- the position of the contact
b- The relationship to the adjacent tooth
c- The esthetics required
d- Extent of caries involvement
e- Extension for prevention

10. 8- The best surface finish on a composite resin restoration
is created by:
a- the 12 fluted finishing burs
b- Fine silica grit disks
c- Lubricated disks
d- The matrix band with no addy finish

11. 9- One should select the shade of composite resin utilizing:
a- bright light
b- Dry shade guide
c- Dry tooth isolated by rubber dam
d- all of the above
e- None of the above

12. 10- The depth of a cavity preparation for resins:
a- is limited to enamel
b- Extends 0.5 mm into dentin
c- Depends on pulpal extent of caries
d- Is 1 mm short of pulp.

13. 11- Instruments used for handling composite resins are
made of:
a- stainless steel
b- Carbon steel
c- Teflon coated
d- Platinum
e- Gold plated
f- a and c
g- c and e
h- None of the above

14. 12- Addition of fillers in resins:
a- increase polymerization shrinkage
b- Decrease polymerization shrinkage
c- Has no effect on shrinkage but increase strength
d- Decrease wear resistance

15. 13- Composite resin restorations are contraindicated in:
a- veneer for metal restoration
b- Class VI cavities
c- Poor oral hygiene
d- Small pit cavities

16. 14- Advantage of composite resin restoration:
a- low modulus of elasticity
b- Anticariogenic property
c- Low thermal conductivity
d- Higher wear resistance

17. 15- Cavity preparations for composite resin restorations do
not require:
a- beveling of cavosurface margins
b- Extension for prevention
c- Acid etching
d- Retentive undercuts
16- Beveling of cavosurface margin in composite resin restorations
a- removes the fluoride-rich enamel
b- Provides more surface area for bonding
c- Provides minimum surface area for bonding
d- a and b
e- a and c
f- None of the above

18. 17- Polishable composites refer to:
a- unfilled resins
b- Conventional composites
c- Microfilled resins
d- All composite resins

19. 18- The color matching for composites when done in a dry
state would make the tooth appear:
a- darker than the adjacent teeth
b- Lighter than the adjacent teeth
c- Same as that of the adjacent teeth
d- Does not have any effect

20. 19- The purpose of acid etching is:
a- to produce surface irregularities in which resins can penetrat
b- To produce a clean enamel surface
c- To increase the surface area of enamel
d- All of the above

21. 20- When there is no need to support functional stresses,
the choice of composite resin in esthetic restoration is:
a- hybrid composite resin
b- Macrfilled composite resin
c- Microfilled composite resin
d- Small particle composite resin

22. 21- the conditioner (etchant) of a typical 3-step dentin bonding
System does which of the following?
a- demineralizes dentin
b- reinforces the smear layer
c- increases dentin permeability
d- a and b
e- a and c
f- b and c
22- bonding of composite to tooth is:
a- micromechanical for dentin but not enamel
b- micromechanical for enamel but not dentin
c- micromechanical to both enamel and dentin
d- not micromechanical

23. 23- it is more difficult to bond to dnetin than to enamel
because:
a- dentin contains more mineralized tooth structure
b- dentin contains more water
c- the presence of the organic smear layer
d- a & b
e- b & c
f- a & c
24-the primer of a typical 3-step dentin bonding system does which of
the following?
a- demineralizes dentin
b- deminerlizes enamel
c- promotes infiltration of dentin by the adhesive
d- inhibits dentin permeability
e- increases the contact angle of the conditioned dentin

24. State whether True (T) or False (F)

25. 1] Smear layer reduces dentin permeability.
2] priming of dentin is mandatory for bonding to both
Enamel and dnetin
3] the diluents used in resin composite not only increases
the wettability but also decreases the polymerization
shrinkage
4] increasing the filler content increases the viscosity of
the material
5] microfilled resin composites are indicated when maximum
esthetics is needed and minimal forces are expected
T
F
F
T
T

26. GLASS IONOMER

27. Choose the most suitable answer

28. 1- Glass ionomer cement has the advantage of:
a- increased opacity
b- Resistance to solubility
c- Adhesive potential
d- all of the above
e- None of the above.
2- Fluoride released from glass ionomer cement has an anticariogenic
effect due to:
a- enhancement of remineralization of tooth structure
b- Formation of more acid resistant fluoroapatite
c- Bacteriostatic or bacteriocidal effect on cariogenic bacteria
d- all of the above
e- None of the above.

29. 3- Root carious lesions are best restored by:
a- glass ionomers
b- Zinc oxide and eugenol
c- Calcium hydroxide
d- a and b
4- What is the powder component in conventional glass ionomer cements?
a- Zinc oxide
b- Polyacrylic acid
c- Methyl methacrylate
d- Fluoro-aluminosilicate glass
e- Calcium oxide.

30. 5- Marginal leakage related to temperature change occurs to the
greatest extent with:
a- amalgam alloy
b- Unfilled resin
c- Composite resin
d- Silicate cement
e- Direct filling gold
6- Itaconic acid in the GIC liquid:
a- Inhibit gelation caused by intermolecular hydrogen bonding
b- Serves as an accelerator
c- Increases the working time and reduces the setting time
d- Reacts with the powder to form the salt gel matrix

31. 7- "Miracle Mix" refers to a:
a- Metal reinforced glass ionomer cement.
b- Type of proportioning of dental amalgam alloy and mercury
c- Superior mixture of filler and resin in composite restoratives
d- None of the above
8- Currently the most effective agent for removing smear layer while
retaining the dentinal plug is:
a- tannic acid
b- EDTA
c- Citric acid
d- Polyacrylic acid

32. 9- An aged patient with high caries index has class III carious lesion
extending onto the root surface. Material of choice to restore the
carious lesion is:
a- composite resin
b- Silicate cement
c- Glass ionomer cement
d- Polycarboxylate cement

33. 10- Metallic instruments should not be used with:
a- composite restorations
b- glass ionomer restorations
c- zinc phosphate cement
d- only a and b
e- only c and d
f- all of the above

34. 11- Which of the following is not an indication for type III
glass ionomer cements?
a- base under resin composite
b- restoration of class III
c- restoration of class V
d- only a and b
e- only b and c
f- none of the above

35. 12- What is the liquid component in Anhydrous glass ionomer
cements?
a- polyacrylic acid
b- itaconic acid
c- water
d- copolymers of polyacrylic acid
13- glass ionomer cement restoration is highly recommended in:
a- cooperative patients
b- good oral hygiee patients
c- patients with low salivary flow
d- patients with high dietary acidic intake
f- all of the above

36. 14- Which of the following is NOT a major use for type II
glass ionomer cements?
a- erosive class V cavities
b- base under resin composite
c- class III carious lesion
d- root caries
15- Which of the following has NOT been used as a part of
the glass ionomer cements?
a- citric acid
b- phosphoric acid
c- hydrochloric acid
d- all of the above

37. 16- conventional glass ionomer cements suffer from:
a- long working time and long setting time
b- short working time and short setting time
c- long working time and short setting time
d- short working time and long setting time