chapter 50 & 51 test

The cervical margins of the provisional should have no more than ___ mm of space between the crown margin and the finish line of the preparation.

0.5

The provisional is trimmed to within ___ mm of the gingival shoulder of the prepared tooth.

1

What is the set time for mixed acrylic before placing it into the mouth?

1 - 2 minutes

What is one disadvantage of using custom provisional coverage?

It can be the most time-consuming prosthesis to make.

Why would the operator "blow" a light stream of air onto the placed light-bodied impression material before seating the tray with heavy-bodied material?

It dries the area.

A cast post is associated with which statement?

It is cemented into the pulp canal. It is made from an acrylic pattern by a dental laboratory technician.

Which statement best describes an indirect restoration?

It is created in a dental laboratory.

Which statement is correct when packing retraction cord?

It is important to place the retraction cord into the sulcus without damaging the surrounding gingival tissues. The placement and removal of gingival retraction cord are expanded functions and may be performed by a dental assistant trained in expanded functions. Generally, the operator removes the cord while the assistant prepares the impression material.

What is the advantage of using preformed crowns for provisional coverage?

It reduces time required for the procedure. Preformed shells come with anatomic features of natural teeth.

How far below the margin of the preparation should the provisional crown sit?

It should be flush with the margin.

Which statement is incorrect about retention pins?

Retention pins can be used only if the tooth has been treated endodontically.

Which material could be used for a core buildup?

Self-curing composite material Reinforced glass ionomer cement Amalgam

When is laboratory-fabricated coverage used?

Several teeth have been prepared, such as in a multiunit bridge

Which device is used to determine the tooth color for ceramic crowns or bridges?

Shade guide

Which procedure takes place during the second appointment for the placement of a cast restoration?

Try-in

What is the setting time for the resin placed in a preformed crown?

90 - 120 seconds

If the liquid or powder acrylic material is being used for the provisional, how many drops of liquid are used?

10

How long does a provisional crown or bridge normally need to last?

2 weeks to 1 month

Once the acrylic-loaded impression is on the prepared tooth, it should remain on the tooth for approximately how long?

3 minutes

Which statement best defines the qualifications of a prosthodontist?

A dentist who is dedicated to restoring and replacing teeth, focusing on fixed or removable prosthodontics. A dentist who has received an additional 3 years of training in a program accredited by the American Dental Association.

Which indirect restoration is minimally invasive and can be used in selected situations, such as a replacement for a congenitally missing lateral incisor?

A resin-bonded bridge A Maryland bridge

Which component of a fixed bridge anchors to existing teeth?

Abutment

What should be done if the margins of the provisional are not adequate?

Add material at the inner aspect of the margin and then reseat the provisional for setting.

During a crown preparation appointment, when are preformed provisional crowns tried on for size and shape?

After

When is a thermoplastic tray, used to fabricate a custom provisional, made?

Before the dentist prepares the teeth

Which cast restoration is designed to fit snugly within a tooth preparation, such as a Class II restoration, and covers only a portion of the occlusal and proximal surface?

Inlay

Which statement is correct regarding prefabricated temporary crowns?

Cellulose acetate is a thin clear shell available in all tooth types.

What occurs at the final appointment in the crown and bridge process?

Cementation of a final restoration

What is the tapered finish line of the margin at the cervical area of a tooth preparation?

Chamfer

What is the final step after cementing the provisional crown?

Check the occlusion.

What is the most common method to obtain gingival retraction?

Chemical retraction

How is the area under the pontic of a bridge maintained?

Clean under the pontic using floss and a floss threader.

Which type of retraction cord is contraindicated for patients with a history of cardiovascular disease?

Cord impregnated with epinephrine

Which statement is a contraindication for provisional coverage?

Cover the facial of a veneer preparation.

What is the most common type of provisional coverage used for crown and bridge preparations?

Custom-made

Which items should be included on the laboratory prescription?

Dentist's name, license number, address, and signature Type of prosthesis requested Date when the case is expected back

When one or more teeth are missing from the same arch, which permanent restoration is recommended?

Fixed bridge

What home care instructions are given for a patient with provisional coverage?

If the provisional comes off, contact the office immediately so it can be put back on.

Which procedure would require a patient to wear a provisional prosthesis for

Implants or periodontal therapy

What could occur when fabricating a provisional if undercuts are present on proximal surfaces?

Locking on

Which statement best represents an important step in the construction and placement of veneers?

Match the tooth color of the veneer to the adjacent teeth.

Which material is placed under a porcelain veneer to mask tooth discoloration?

Opaque liner

Which provisional preformed crowns are used on anterior teeth when appearance is important?

Polycarbonate

Which component of a fixed bridge replaces a missing natural tooth?

Pontic

What is the material of choice for an inlay or onlay restoration if esthetics is a concern?

Porcelain

Which of the following is an example of a fixed prosthesis?

Porcelain veneer

What is the name for a full metal crown that is covered in a thin layer of porcelain?

Porcelain-fused-to-metal crown

What is the name for the opening into which a post is cemented?

Post channel

Methyl methacrylate is an example of which of the following types of materials commonly used for custom provisional coverage?

Powder/liquid materials

Which provisional uses a polymer shell filled with a composite resin that bonds with the preformed crown and tooth?

Preformed polymer

When would a stainless steel crown be used for provisional coverage?

Primary posterior teeth

Which of the following is appropriate patient home care instruction for someone with provisional coverage?

Pull floss through the contact, either to the facial or lingual side, once floss is placed below the contact.

Which cement is most commonly used with provisional crowns?

Temporary

Which of the following statements is correct concerning porcelain veneers?

The color of the finished veneer can be affected by the shade of the underlying tooth structure and by the color of the luting agent.

Which statement is incorrect about prefabricated crowns?

The crowns are available for bridges as well as for single units.

Which statement is correct regarding a fixed bridge?

The fixed bridge is described by the number of units involved. A fixed bridge consists of at least one abutment and one pontic.

What is an indication for prescribing fixed prosthodontics?

The patient wants it. One or two adjacent teeth are missing in the mouth. Suitable abutment teeth are present.

Under which condition would a post-and-core be recommended before placing a crown?

The tooth has been treated endodontically.

Which statement is correct regarding preformed polycarbonate crowns?

They can be used as a mold to fabricate a custom provisional.

Which type of crown does not cover the entire anatomic portion of the tooth?

Three-quarter

Why is it necessary to keep the preliminary alginate impression moist?

To keep the alginate from distorting

What is the purpose of provisional coverage?

To maintain or restore tooth function, or both To provide comfort for the patient while the permanent restoration is being fabricated To protect the margins of the prepared tooth

What is the purpose of a core buildup?

To provide a larger area of surface retention for cementation To replace large areas of missing tooth structure To support the cast crown

What is the term for each component of a fixed bridge?

Unit

How is a Maryland bridge held in place?

Winglike extensions are bonded onto the lingual surfaces of the adjacent teeth

A gingival retraction cord is placed _____ the crown preparation is completed; it is removed _____ the final impression is taken.

after; before

The two types of provisional coverage include _____ and _____.

custom; prefabricated

The occlusal surface of the provisional coverage should sit _____ the occlusal plane of the adjacent teeth.

even with

Why is the provisional placed on the tooth in the patient's mouth for the final curing stage?

o avoid excess shrinkage of the provisional during the final curing stage