Principles of Tooth Preparation Multiple Choice Questions
1. The average root surface area of maxillary first molar is (in mm2):
A. 133
B. 233
C. 333
Answer: D. 433
2. The average root surface area (mm2) of the maxillary second premolar is:
A. 234
Answer: B. 220
C. 273
D. 204
3. Ante’s law is followed in the construction of:
A. Complete denture
Answer: B. Fixed partial denture
C. Removable partial denture
D. All of the above
4. Extra retention in abutment teeth is obtained with:
A. Dovetail
Answer: B. Slots, pins and grooves
C. Outline form
D. Increasing tooth reduction
5. The forces acting through a fixed partial denture on the abutment tooth should be directed:
A. As far as possible at right angles to the long axis of the teeth
Answer: B. Parallel to the long axis of the teeth
C. By decreasing the , mesiodistal dimension
D. None of the above
6. Supplementary retention on the abutment tooth is made possible by:
A. Greater bulk of the metal
B. Proper cementation technique
C. Shoulder preparation
Answer: D. Proper use of pins and grooves
7. Male component of pier abutment is placed on:
Answer: A. Mesial side of pontic
B. Distal side of pontic
C. Mesial side of abutment
D. Distal side of abutment
8. In FPD, retention is provided by:
A. Cement
Answer: B. Parallel walls
C. Grooves
D. Proximal slice
9. Structural durability is a:
A. Biological phenomenon
Answer: B. Mechanical phenomenon
C. Sructural phenomenon
D. None of the above
10. Which of the following may least be used as an abutment?
A. Tooth with minimum crown
Answer: B. Tooth with short tapered crown and conical roots
C. Rotated and tipped tooth
D. Pulp treated tooth
11. When the height and taper of the preparation are same, which of the following provides better resistance?
A. Large diameter molar
B. Small diameter molar
C. Large diameter premolar
Answer: D. Small diameter premolar
12. Optimum crown to root ratio of the tooth to be used as abutment is:
A. 1:2
Answer: B. 2:3
C. 1:1
D. 2:1
13. Over contoured crowns are most often the results of:
Answer: A. Insufficient tooth reduction
B. Overbuilding by technicians
C. Desirable if properly shaped
D. Increases retention
14. The functional cusps are beveled in the preparation of posterior cast crowns:
A. to reduce the stress at the line angles
B. to prevent the fracture of the tooth structure
Answer: C. for the structural durability of the restoration
D. to help in the retention
15. Ante’s law provides an aid for:
A. Selection of pontic
B. Selection of connector
C. Selection of retainers
Answer: D. Selection of abutments
16. Ante’s law concerns the:
A. degree of tipping allowable in an abutment tooth
B. amount of curvature acceptable at the plane of occlusion
C. Amount of increase in retentive factor with a full crown versus a three quarter crown
D. None of these
17. The taper that should be present in a prepared tooth as abutment for FPD is:
A. 10 degrees
Answer: B. 6 degrees
C. 2 degrees
D. not important
18. The ideal crown preparation has a degree of convergence from gingival finish line towards occlusal is:
A. 2-4 degrees
Answer: B. 3-5 degrees
C. 4-9 degrees
D. 8-11 degrees
19. An anterior FPD is contraindicated when:
A. Abutment teeth are non carious
B. An abutment tooth is inclined 15 percent
Answer: C. There is considerable resorption of the residual ridge
D. Crowns of abutment teeth are long
20. Which of the following teeth is the least desirable to use as an abutment tooth for a FPD?
A. Tooth with pulpal innvolvement
B. Tooth with minimal coronal structure
C. Tooth rotated and tipped out of line
Answer: D. Tooth with short, tapered root with long clinical crowns
21. Predicatble compliment of optimum tooth preparation should satisfy:
A. Biological requirement
B. Esthetic requirement
C. Combination of compromises among the prevalent biological and mechanical considerations
Answer: D. Biological, mechanical and esthetic requirement
22. The posterior tooth that gives a better support is:
A. With convergent roots
B. Divergent roots
C. Conical roots
Answer: D. Curved roots
23. The posterior tooth that gives a better support is:
A. With convergent roots
Answer: B. Divergent roots
C. Conical roots
D. Curved roots
24. A pier abutment is:
A. Periodontally weak abutment
Answer: B. With an edentulous space on mesial and distal sides of the abutment
C. Edentulous space on one side of the abutment
D. Abutment adjacent to edentulous space
25. In case, if maxillary canine is missing and we have to make a tooth supported FPD, abutment will be:
Answer: A. Central incisor, lateral incisor, and first premolar
B. Lateral incisor, First premolar and second premolar
C. Lateral incisor and first premolar
D. It depends upon periodontal status of remaining teeth
26. Pivoting movement is better resisted by a tooth preparation if:
Answer: A. Diameter is smaller
B. Diameter is large
C. Diameter is large and length is small
D. Do not depend upon diameter of tooth
27. Cavosurface margin angulation in chamfer finish line is:
A. Always 90 degrees
B. 90 degrees or less than 90 degrees
Answer: C. 90 degrees or more than 90 degrees
D. 120 degrees
28. To increase resistance form of an excessively tapered preparation:
A. Reduce height of preparation to shorten arc of rotation
B. Increase cervical reduction to taper
Answer: C. Add groove
D. Use adhesive cement
29. Ante’s law concerns the:
A. Degree of tipping allowable in the abutment tooth
B. Amount of increase in retentive factor with a full crown versus a 3/4th crown
C. Crown:Root ratio
Answer: D. Ratio of combined pericemental root surface area of the abutment teeth and the pericemental root surface areas of the teeth to be replaced
30. Functional cusp bevel is given for:
A. Marginal integrity
Answer: B. Structural durability
C. Retention and resistance form
D. To improve the geometry of the tooth surface
31. Grooves placed in vertical walls of bulk tooth structure must be:
Answer: A. At least 1.0 mm
B. At least 2.0 mm
C. At least 1.5 mm
D. At least 1.2 mm
32. Uniform reduction on the tooth surface may be ensured by the placement of:
A. Pins
Answer: B. Depth grooves
C. Ledges
D. Bevels
33. Occlusal offset in an anterior partial veneer crown may generally be necessary to provide:
A. Retention
B. Conservation of tooth structure
C. Esthetics
Answer: D. Structural durability
34. Recommended convergence between opposing axial walls, which optimize retention, is:
Answer: A. 6 degrees
B. 10 degrees
C. 15 degrees
D. 45 degrees
35. Overall optimum degree of taper of tooth preparation for maxillary anterior tooth is:
A. 6 degrees
Answer: B. 10 degrees
C. 14 degrees
D. 19 degrees
36. What is the minimum amount of taper that should be maintained for an ideal tooth preparation?
A. 4 degrees
B. 5 degrees
C. 6 degrees
Answer: D. 12 degrees
37. To achieve the additional retention following should be done during tooth preparation:
A. Excessive occlusal preparation
B. Tapered Preparation
Answer: C. Grooves and Boxes
D. Supragingival finish line