dental materials (quizzes)

an impression is a ______ reproduction of the teeth

negative

the model created from the impression is a _____ reproduction of the teeth

positive

today what two choices do we have in how we take a dental impression

• traditional material-based impressions

• digital impressions

the most widely irresistible hydrocolloid material for preliminary impressions is _______

alginate

a ______ is constructed in the lab to fit the mouth of a specific patient

custom tray

____ can be used to extend the size of a stock impression tray?

utility wax

what color is a rubber base adhesive?

brown

true or false: alginate material is available in two setting types - fast set or normal set

true

hydro means

water

______ hydrocolloid impression materials cannot return to the sol state after they become a gel

irreversible

what does CAD stand for?

computer-aided design

where is CAD/CAM used?

in both the dental office and the dental laboratory

which of the following CAD/CAM procedures is the dental assistant able to perform?

• turn on the computer and ready the computer programs

• set up the scanner to create a digital impression

• prepare the ceramic block to be milled

• all of these

all of these

with CAD/CAM training the dental assistant can compete all of the following except?

• scan the cavity preparation to create a digital impression

• create the digital restoration using the CAD system

• send the digitized restoration to the CAM for milling without the dentists evaluation and consent

• place the ceramic block in the milling machine

send the digitized restoration to the CAM for milling without the dentists evaluation and consent

what is not an advantage of CAD/CAM?

the fee is reduced because there is not dental laboratory involvement

which of the filling is not a component of CAD/CAM?

• intraoral camera (scanner)

• CAD/CAM software

• milling machine

• gold or gold alloy blocks

gold or gold alloy blocks

restorations using CAD/CAM technology in the dental office and laboratory are

completed in one or two appointments

CAD/CAM systems sometimes use a ____ to obtain an enhanced digital image

reflective powder

which of the following is not true regarding CAD/CAM?

• images of the occlusion or bite registration are scanned before the tooth is prepared

• no shade needs to be taken; the computer selects the shade to match the patients teeth

• the digitized impression can be modified to enhance the gingival margins of the preparation

• diamond burs and water are used during the milling process of the ceramic block

no shade needs to be taken; the computer selects the shade to match the patients teeth

the patients should be made aware of the shorted appointment time for CAD/CAM and the greater cost of the restoration as compared to a traditional lab fabricated cast restoration

the first statement is true, second is false

is an impression a negative or positive reproduction?

negative reproduction

which type of impression is used to record occlusal relationships

bite registration

which type of impression tray covers half of the dental arch?

quadrant tray

which type of impression tray allows impression material to lock into the tray mechanically

perforated tray

which tray of impression tray is designed to fit a specific patient

custom tray

what material can be used to extend the length of an impression tray?

utility wax

what is the most widely used irreversible hydrocolloid for preliminary impressions?

alginate

what organic substance found in hydrocolloid materials is derived from seaweed?

potassium alginate

why would you select a fast set alginate instead of a normal set alginate?

the patient has a strong gag reflex

what is the water-to-powder ratio for taking a maxillary impression, according to the procedure used in this course

3 scoops of powder to 3 scoops of water

hydro means

water

do you mix irreversible hydrocolloid on a paper pad or in a mixing bowl?

in a rubber mixing bowl

before an impression is taken with reversible hydrocolloid, where is the material kept?

conditioning bath

is an elastomeric material used for preliminary impressions or final impressions

final impressions

in which three forms are elastomeric materials supplied?

light, regular, heavy

what technique is used to place light-body material round a prepared tooth?

a special syringe or extruder

what impression material will the dentist first apply to a prepared tooth?

light-body

what system completes the mixing of final impression material for you?

automix system

what is another term for polysulfide

rubber base

which type of bite registration material is most popular?

polysiloxane paste

what is done during the CAD portions of the CAD/CAM process

a scanner creates a digital model of the preparation

what are the advantages of using a CAD/CAM system?

• faster productions

• fewer appointments

• improved accuracy

what are the disadvantages of using a CAD/CAM system?

• equipment/software maintenance

• need for training

• high equipment cost