Practice Midterm: Chapters 45, 47-49

Model plaster

Which of the following gypsum products has the highest powder-to-water ratio?

TRUE

If used as a base, zinc phosphate requires the use of a liner first.

It is equally as important as when you are with a patient.

Which statement regarding infection control in the dental laboratory is accurate?

Stringy or weblike

How should polycarboxylate cement appear once setting has initiated?

Slowly

How should the patient bite when positioning the bite-fork during a face-bow registration?

bite record & centric relation both a and c

The ______ is the measurement of where the teeth are positioned when the joints are aligned correctly and before the teeth actually come together.

Luting

Which type of dental cement is used as an adhesive for permanent indirect restorations?

anatomical; art

A model consists of the _____ portion, which represents the teeth and tissues of the mouth, and the _____ portion, which forms the base of the cast.

Zinc phosphate

Which cement is the most acidic and irritating to the pulp?

Baseplate

Which type of dental wax is used to construct occlusal rims and set denture teeth in the wax-up?

Midline

When taking a face-bow registration, the vertical indicator rod should be aligned with which oral landmark?

Weaker

How will gypsum material be affected if additional powder is added after mixing has begun?

In large amounts

Which technique listed would be incorrect when pour an impression?

TRUE

Properly mixed glass ionomer cement should have a glossy appearance.

Dental lathe

Which item is used to polish or trim custom trays, provisional coverage, dentures, and indirect restorations?

Thermoplastic

Which type of resin is formed into a diagnostic model using heat and a vacuum former?

a mouth guard

When constructing ______ with a vacuum former, use a heavier-gauge, flexible plastic that does not require a spacer but does require an attachment for the strap.

Improper pouring of the impression

What causes air bubbles in a model?

both a and b Composite resin
Glass ionomer

Which type(s) of cements can be light-cured?

For 2 minutes

How should light-cured resin tray material be cured?

Mix slowly.

Which technique will help to dissipate heat when mixing zinc phosphate cement?

On a glass slab

How should glass ionomer cement be mixed to increase the working time?

After 24 hours

After fabrication, when can a self-cured resin custom tray be used?

Glass ionomer

Which cement inhibits recurrent decay?

Humidity
Temperature
Mixing time
All of the above

Which factor(s) influence the cementation procedure?

both a and b
Free of all plaque and debris
Etched or treated with a bonding system

When composite resin cement is used, how should the tooth surface be prepared?

Add a thin lining to cover all internal walls of the casting.

How should cement be placed into an indirect restoration for delivery?

Use a gentle stream of air to remove excess moisture.

What should be done to an impression before pouring?

stops

Which of the following is used to prevent a custom impression tray from sitting too deeply when taking the impression?

Dry the enamel and dentin completely.

Which statement is incorrect as it relates to preparing a tooth for a composite restoration?

The inverted-pour method consists of mixing one large mixture of plaster or stone and pouring both portions of the model in a single step.

Which of the following statements correctly describes the pouring methods used to create the base portion of a dental model?

Articulator

What device that holds maxillary and mandibular models in an occlusal relationship?

Type I ZOE

What type of cement is frequently used to cement provisional crowns?

Placing a provisional crown

When are temporary cements used?

Pull excess cement down away from the casting.

Which method would not be used to remove excess cement from an indirect restoration?

Separation medium

Before constructing a light-cured tray, what would be painted on the model?

Follow the manufacturer's instructions.

Which statement best represents the dental assistant's priority when preparing dental cements?

Results can vary.

Which factor is not an advantage of using glass ionomer in premeasured capsules?

Composite resin

Which type of cement is preferred for cementation of ceramic veneers?

I

Which type of glass ionomer cement is used to cement orthodontic appliances?

Amalgam

Which is an example of a direct restorative dental procedure?

Both a and b

An example of esthetic dentistry includes which procedure?

Mesial

During a class III restoration, the dentist will enter the tooth from which surface to minimize the size of the restoration?

inner knob

The ______ is used to decrease the size of the matrix band loop after the band has been placed on the tooth.

Intermediate

A temporary restoration that can be placed in any tooth or tooth surface for a short period is also known as which type of restoration?

Cavity wall

What are the internal surfaces of a cavity preparation called?

The class V lesion occurs on the incisal third of the facial and lingual surface of any tooth.

Which of the following statements is true?

General dentist

Who performs the majority of operative dental procedures?

the size and position of the pulp of the tooth.

Complete the statement: "When completing a permanent restoration, the dentist should have knowledge of:

It is as effective as other tooth-whitening methods.

Which statement is incorrect regarding brush-on whitening methods?

Between the band and wedge

For there to be a solid closure of margins on a posterior composite restoration, where should the prongs of the tension ring for the Palodent system be placed?

Overhang

What is the term for excess restorative material that extends beyond the cavity margin?

Mandrel

How would an anterior matrix band be contoured?

Preparing, mixing, and transferring dental materials

What are a dental assistant's responsibilities in a restorative procedure?

Either a or c

Which type of matrix system is used for the primary molars?

Outer guide slots

What is the component of a universal matrix retainer that serves to guide the direction of the matrix loop according to the quadrant that is being treated called?

Ensure that the final restoration will have proper contact with the adjacent tooth.

Why is a matrix band contoured prior to placing the restorative material?

Both b and c

A matrix must be used to create a temporary wall for which of the following classifications of tooth restoration?

Palodent

Which matrix system that is used with posterior composite restorations?

On the buccal surface of the tooth being restored

The universal, or Tofflemire, retainer holds the matrix band snugly in position. It is most often positioned in which area?