Fixed 1 Midterm

The full-coverage crown and its preparation:

• may protect weakened tooth structure

• requires more tooth structure removal than an intercoronal restoration

• encircles all the remaining coronal tooth structure

• A and C

• A, B, and C

Indications for placement of a full-coverage crown may include:

• teeth with large existing restorations

• cracked tooth

• broken cusps

• the patient desires a more esthetic tooth

• all of the above

Which of the following is NOT one of the principles of tooth preparation?

• preservation of the periodontium

• preservation of the pulpal innervation

• preservation of tooth structure

• retention and resistance form

• marginal integrity

4. ____________ prevents dislodgment of a restoration by forces directed in apical or oblique directions.

• resistance

• retention

• abrasion

• adhesion

Crown preparations are tapered (converge occlusally) to:

• allow us to visualize the preparation walls from the occlusal direction

• eliminate axial wall undercuts

• create maximal retention for the preparation

• A and B

• A, B, and C

The acceptable range for crown preparation convergence of the total axial walls in our course is _____ degrees.

• 0-10

• 0-16

• 5-20

• 6-16

• 10-20

While longer axial wall lengths are generally more retentive, the minimal axial wall length should be _____ mm.

• 2-3

• 3-4

• 4-7

• 5-8

• 6

__________________ is the imaginary line in which a restoration can be placed onto or removed from a preparation.

• resistance form

• path of insertion

• freedom of displacement

• principle of substitution

• structural durability

The complete gold crown (full gold crown) preparation should include each of the following reduction guidelines EXCEPT one. Which one is the EXCEPTION?

• 1.0 mm on the non-functional cusp

• 1.5 mm on the functional cusp

• 0.7-1.0 mm buccal and lingual axial reduction

• 0.7-1.0 mm chamfer thickness

• 0.3-0.5 mm chamfer thickness

The Exaflex putty impression prior to beginning tooth preparation for a full gold crown:

• is made with a vinyl siloxane impression material

• is used as a mold for the provisional crown restoration that is placed at the end of the preparation appointment.

• is used to form the wax pattern for the full gold crown

• A and B

• A, B, C