MCQs on Principles of Cavity Preparation

1.A prepared cavity is best protected from moisture by:

Cotton rolls
Saliva ejector
Rubber dam
Paper napkin

2. Retentive grooves in the proximal box of a class II amalgam cavity should be:
Sharp and elongated at the dentinoenamel junction
Round and elongated in the dentin
Round and short in the dentin
Sharp and elongated in the dentin

3. Incipient caries consists of opaque, chalky white areas that appear when the tooth surface is dried, this is referred as :
White spot
Hot spot
Translucent zone
Body of lesion

4. Smear layer consists of:
Enamel debris
Micro organismas
Dentinal chips
All of the above

5. A butt joint is a :
70 degree joint
90 degree joint
120 degree joint
180 degree joint

6. Enameloplasty is:
is same as prophylactic odontomy
filling of enamel fissures with amalgam
elimination of shallow enamel fissures
All of the above

7. The term "primary prevention" means all of the following except :
Planning the patient's diet
Prophylactic odontomy
Topical application of fluoride
Extending cavity preparation to prevent recurrence

8. Cavities beginning in the proximal surfaces of bicuspids and molars are?
Class I
Class II
Class IV
Class VI

9. "Saucering" out of small pits tom improve self cleansing property is called :
Saucerisation
Odontomy
Enameloplasty
None of the above

10. Deepening of the pulpal floor during cavity preparation provides for:
Outline form
Retention form
Convenience form
Resistance form

11. In which type of the lesion "eburnation" of the dentin is seen?
Acute Caries
Chronic caries
Arrested caries
Root caries

12. Resistance form is that shape of the cavity which:
prevents displacement of the restoration
permits the restoration to withstand occlusal forces
allows adequate instrumentation
allows the restoration to withstand occlusal forces and prevent displacement

13. Which of the following is the commonly recommended procedure for debridement?
Citric acid
Hydrogen peroxide 10%
Air and water spray
Hydrochloric acid

14. The axiopulpal depth of the proximal box in class II cavity is:
0.2-0.8 mm into dentin
0.5-1 mm into dentin
1 to 2 mm into dentin
2 to 3 mm into dentin

15. The base of class III preparation is:
Axial wall
Facial wall
Gingival wall
Lingual wall

16. To avoid pulpal irritation below a resistant metallic restoration, the minimum dentin thickness which should remain is:
0.5 mm
1.5 mm
1.0 mm
2.0 mm

17. The most common cause of fracture at the isthmus of class II dental amalgam restoration is ?
Delayed expansion
Inadequete depth at the isthmus area
Inadequete width at the isthmus area
Moisture contamination of the amalgam during placement

18.While preparing occlusal cavity for amalgam in mandibular first premolar, the bur:
is kept absolutely vertical
is tilted slightly bucally
is tilted slightly lingually
can be kept in any direction