Chapter 46- Impression Material

A(n) ___ is a gel or sol substance with its particles suspended in a water-based medium.

colloid

___ is the process of using the finger to achieve a closer adaptation of the edges of an impression

border molding

A(n) ___ impression material has elastic properties and is made from rubber

elastomeric

A foundation or basic ingredient of a material is the

base

To have something ____ is to have it centered, such as the maxillary teeth centered over the mandibular teeth

centric

___ is a gelatin-type material derived from seaweed

agar

___ is the loss of water, which causes shrinkage

syneresis

___ is a way of bringing a material to a desired temperature and consistency

tempering

___ describes a property of fluids with a high resistance to flow

viscosity

___ is the material of choice in dentistry for preliminary impressions

alginate

___ is to transform a material from one physical state to another

hysteresis

___ means water

hydro

A(n) ___ is a reproduction of someone's bite with the use of bite wax or elastomeric material

occlusal registration

A(n) ___ is a substance that modifies or increases the rate of chemical reaction

catalyst

___ is the absorption of water, which causes an object to swell

imbibition

An impression would be considered a

negative reproduction

Of the three classifications of impressions, which could a EDFA do.

preliminary and bite registration

Of the three classifications of impressions, which would be used by the dental lab tech for determining occlusal relationship

bite registration

Which type of stock tray would be selected and prepared to cover half of an arch?

quadrant

Which type of impression tray allows the impression material to mechanically lock on?

perforated

Which type of tray is constructed to fit the mouth of a specific patient?

custom

___ would be used to extend the length of a tray to accommodate third molars

utility wax

The organic substance of hydrocolloid material is

seaweed

Why would you select fast-set alginate when taking a preliminary impression?

the patient has a strong gag reflex

The powder/water ration for a maxillary preliminary impression is

3 scoops powder / 3 measures of water

Hydro- means

water

Irreversible hydrocolloid material is also referred to as

alginate

On or in what is irreversible hydrocolloid material mixed?

mixing bowl

Where would reversible hydrocolloid material be placed prior to taking the impression

conditioning bath

Elastomeric materials are intended for what type of impression

final

How is an elastomeric material supplied?

paste, cartridge, putty

Which viscosity of a final impression material is applied first to the prepared tooth or teeth.

light bodied

Another name for polysulfide is

rubber base

How is the light-body impression material applied during the final impression procedure

extruder with tip

What additional method can be used to mix final impression material instead of using an extruder?

spatula and pad

___ is the material universally used for taking bite registration

baseplate wax

What type of tray is most commonly selected when zinc oxide-eugenol bite registration material is used?

gauze

Baseplate wax is ___ before being placed in the patient's mouth for a bite registration

warmed

While the dentist is dispensing the syringe material around the prepared tooth, what should the dental assistant be doing during a final impression procedure?

readying the tray with heavy-body material

A preliminary impression is ___ before being transported to the lab for pouring up

rinsed, disinfected, wrapped in a moist paper towel and placed in a precautionary bag

The centric relationship of the upper and lower arches is recorded in the

bite registration and occlusal registration

A smooth impression tray is coated with a(n) ____________ before the final impression material is placed in the tray.

Adhesive

In terms of a final impression, wash is a term used to describe the

syringe-type material

To avoid air bubbles in a final impression, the heavy body material is

extruded, keeping the tip in the material

The gloves that must be worn when kneading silicone putty for an impression are

vinyl

Polysiloxane is a type of ____________ silicone impression material.

addition

The vacuum former is used to create a

custom tray, mouth guard, night guard vital bleaching tray

In the __________ bite registration technique, the patient is instructed to close his or her teeth together before the impression material is placed.

Closed

Gloves must be worn when handling

preliminary impressions, final impressions and laboratory case

In a two-step impression technique, before seating the heavy body impression material,

the syringe-type material is placed around the tooth

An impression tray with a smooth surface must be _________________ before use.

Painted with an adhesive substance

The final cure of an elastomeric impression material can occur

within 15 minutes

When an extruder is used, the impression material is mixed

as it moves through the mixing tip

The tubes of catalyst and base are interchangeable if they are

the same type of impression material

The impression material that has a very strong odor and will permanently stain clothing is

polysulfide

To prevent a custom tray from seating too far on the arch, _______ are created.

spacers

When mixing an alginate product, the warmer the water is, the ______ the set will be.

faster

A maxillary alginate impression usually requires ____ scoops of powder and three measures of water.

three

Normal-set alginate has a working time of

2 minutes

If stored in water, an alginate impression

absorbs water