Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Occlusion > Alginate and Dental Stone > Flashcards

Alginate and Dental Stone Flashcards

1
Q

SKIPPED

the ideal impression material

A 
EASY TO MIX AND HANDLE.
SUITABLE WORKING TIME.
SUITABLE SETTING TIME.
COMPATIBLE WITH STONE
NOT TOXIC OR ALLERGENIC TO THE PATIENT.
DIMENSIONALLY STABLE ON SETTING.
ACCURATE TO RECORD THE FINE DETAILS
HAS ACCEPTABLE ODOR AND TASTE.
ADEQUATE STRENGTH.
ADEQUATE SHELF LIFE.
ECONOMICAL
 READY TO BE DISINFECTED WITHOUT LOSS OF ACCURACY.
 FLUID OR PLASTIC WHEN INSERTED INTO THE MOUTH.
IT MUST BE AN EXACT RECORD OF ALL THE ASPECTS 
OTHER TEETH AND TISSUE SURROUNDING 
IT MUST BE FREE FROM AIR BUBBLES ESPECIALLY IN THE FINISH LINE AREA.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

key properties of impresion materials (2)

A

accuracy

dimensional stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

accuracy

A

ability to replicate the intraoral surface details

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

dimensional stability

A

ability to retain its absolute dimensional size over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

nonelastic impression materials (4)

A

gypsum (plaster)
impression compound
zinc oxide eugenol
impression waxes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

elastic impression material (2)

A

hydrocolloids

non aqueous elastomers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

hydrocolloids (2)

A

agar reversible

alginate irreversible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

non aqueous elastomers (4)

A

polysulfide
polyethers
condensation silicone
addition silicone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

ALGINATE

(IRREVERSIBLE HYDROCOLLOID)(IRREVERSIBLE HYDROCOLLOID) was developed as a substitute for

A

AGAR IMPRESSION
MATERIAL WHEN ITS SUPPLY BECAME SCARCE DURING WORLD
WAR II.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

ALGINATE IS BASED ON A NATURAL SUBSTANCE EXTRACTED FROM CERTAIN — —. THE SUBSTANCE IS CALLED

A

BROWN SEAWEED
ANHYDRO-Β-D-
MANNURONIC ACID OR ALGINIC ACID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

THE PRINCIPAL FACTORS RESPONSIBLE FOR THE SUCCESS OF THIS

TYPE OF IMPRESSION MATERIAL ARE THAT IT IS (3)

A

EASY TO MANIPULATE,
COMFORTABLE FOR THE PATIENT,
AND RELATIVELY INEXPENSIVE SINCE IT DOES NOT REQUIRE ELABORATE EQUIPMENT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

THE CHIEF ACTIVE INGREDIENT OF THE IRREVERSIBLE
HYDROCOLLOID IMPRESSION MATERIALS IS ONE OF THE SOLUBLE
ALGINATES, SUCH AS (3)

A

SODIUM,
POTASSIUM,
OR TRIETHANOLAMINE ALGINATE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

WHEN THE SOLUBLE ALGINATES ARE MIXED WITH WATER,

THEY FORM A – QUITE READILY

A

SOL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

alginate composition (6)

A 
potassium alginate 
calcium sulfate 
zinc oxide 
potassium titanium fluoride 
diatomaceous earth
sodium phosphate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

potassium alginate
function:
weight percentage:

A

soluble aginate

15

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

calcium sulfate
function:
weight percentage:

A

reactor

16

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

zinc oxide
function:
weight percentage:

A

filler particles

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

potassium titanium fluoride
function:
weight percentage:

A

accelerator

3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

diatomaceous earth
function:
weight percentage:

A

filler particles

60

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

sodium phosphate
function:
weight percentage:

A

retarder

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

THE TYPICAL SOL-GEL REACTION CAN BE DESCRIBED SIMPLY

AS A REACTION OF

A

SOLUBLE ALGINATE WITH CALCIUM SULFATE
AND THE FORMATION OF AN INSOLUBLE CALCIUM ALGINATE
GEL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

IN THE CLINICAL SETTING, IT IS TEMPTING TO ALTER THE
SETTING TIME BY CHANGING THE W/P RATIO OR THE MIXING
TIME. THIS SLIGHT MODIFICATION CAN HAVE MARKED EFFECTS
ON THE (3)

A

PROPERTIES OF THE GEL,
THE TEAR STRENGTH,
AND THE ELASTICITY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

THE CLINICIAN, HOWEVER, CAN SAFELY INFLUENCE THE
SETTING TIME BY ALTERING THE — OF THE
WATER.

A

TEMPERATURE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

ALGINATE IMPRESSION MATERIALS ARE —, SO

MOIST TISSUE SURFACES ARE NOT A PROBLEM

A

HYDROPHILIC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
GENERALLY, ALGINATES ARE USED AS A
FIRST PRELIMINARY IMPRESSION TO CONSTRUCT A CUSTOM TRAY FOR A MORE ACCURATE SECOND IMPRESSION OR TO MAKE STUDY MODELS TO HELP WITH TREATMENT PLANNING AND DISCUSSIONS WITH THE PATIENT.
26
SKIPPED | MAKING AN ALGINATE IMPRESSION (7)
1. THE MEASURED POWDER IS SIFTED INTO PREMEASURED WATER THAT HAS ALREADY BEEN POURED INTO A CLEAN RUBBER BOWL. 2. THE POWDER IS INCORPORATED INTO THE WATER BY CAREFULLY MIXING WITH A METAL OR PLASTIC SPATULA THAT IS SUFFICIENTLY FLEXIBLE TO ADAPT WELL TO THE WALL OF THE MIXING BOWL. ALL OF THE POWDER MUST BE DISSOLVED. 3. THE RESULT SHOULD BE A SMOOTH, CREAMY MIXTURE THAT DOES NOT READILY DRIP OFF THE SPATULA WHEN IT IS RAISED FROM THE BOWL. 4. BEFORE SEATING THE IMPRESSION, THE MATERIAL SHOULD HAVE DEVELOPED SUFFICIENT BODY SO THAT IT WILL NOT FLOW OUT OF THE TRAY AND GAG THE PATIENT. 5. THE MIXTURE IS PLACED IN A SUITABLE TRAY, WHICH IS THEN PLACED IN THE MOUTH. IT IS IMPERATIVE THAT THE IMPRESSION ADHERE AND BE RETAINED TO THE TRAY SO THAT THE IMPRESSION CAN BE WITHDRAWN FROM AROUND THE TEETH. 6. ALGINATE IS VERY WEAK; THEREFORE THE TRAY MUST FIT THE PATIENT'S ARCH SO THAT THERE IS A SUFFICIENT BULK OF MATERIAL. THE THICKNESS OF THE ALGINATE IMPRESSION BETWEEN THE TRAY AND THE TISSUES SHOULD BE AT LEAST 3 MM. 7. ALGINATE HYDROCOLLOID MATERIALS ARE STRAIN- RATE DEPENDENT. THUS THE TEAR STRENGTH IS INCREASED WHEN THE IMPRESSION IS REMOVED WITH A SNAP.
27
mixing time
45 s to 1 min
28
THE THICKNESS OF THE ALGINATE IMPRESSION BETWEEN THE TRAY AND THE TISSUES SHOULD BE AT LEAST - MM.
3
29
impression disinfection
disinfectant soaked paper towel/plastic bag, 10 min
30
does disinfection affect VPS?
not adversely affected
31
HYDROCOLLOIDS | •• IMBIBITION:
EXPANSION AFTER 10 MIN
32
POLYSULFIDE, POLYETHER | •• POTENTIAL EXPANSION,
increase exposure time
33
digital impressions (2)
* LESS FOCUS ON RESEARCH AND DEVELOPMENT OF IMPRESSION MATERIALS * DIGITAL IMPRESSIONS, SCAN AND THEN SEND ELECTRONIC FILE
34
SOME CURRENT digital impression SYSTEMS: (3)
crerec itero element LAVA
35
which digital impression system will we use in lab?
cerec
36
CHEMICALLY, THE GYPSUM PRODUCED FOR DENTAL APPLICATIONS | IS NEARLY PURE
CALCIUM SULFATE DIHYDRATE
37
DIFFERENT --- FORMS OF GYPSUM HAVE BEEN USED FOR CENTURIES FOR CONSTRUCTION PURPOSES AND FOR MAKING ARTIFACTS.
CRYSTALLINE
38
GYPSUM PRODUCTS ARE USED IN DENTISTRY FOR THE
PREPARATION OF STUDY MODELS FOR ORAL AND MAXILLOFACIAL STRUCTURES AND AS IMPORTANT AUXILIARY MATERIALS FOR DENTAL LABORATORY OPERATIONS THAT ARE INVOLVED IN THE PRODUCTION OF DENTAL PROSTHESES.
39
WHEN PLASTER IS MIXED WITH FILLERS, SUCH AS DIFFERENT | FORMS OF SILICA, IT IS KNOWN AS A
GYPSUM DENTAL | INVESTMENT
40
THE PRINCIPAL CONSTITUENT OF GYPSUM-BASED PRODUCTS SUCH | AS DENTAL PLASTERS AND STONES IS
CALCIUM SULFATE | HEMIHYDRATE
41
VARIOUS GYPSUM PRODUCTS REQUIRE DIFFERENT AMOUNTS OF WATER AND THESE DIFFERENCES ARE ACCOUNTED FOR PRINCIPALLY BY THE
SHAPE AND COMPACTNESS OF THE CRYSTALS. THESE FACTORS ARE REGULATED BY THE MANUFACTURER
42
THE --- THEORY PROPOSES THAT WHEN MIXED WITH WATER, PLASTER ENTERS INTO THE COLLOIDAL STATE THROUGH A SOL-GEL MECHANISM.
COLLOIDAL
43
THE --- THEORY SUGGESTS THAT REHYDRATED PLASTER PARTICLES JOIN TOGETHER THROUGH HYDROGEN BONDING TO THE SULFATE GROUPS TO FORM THE SET MATERIAL.
HYDRATION
44
HOWEVER, THE MOST WIDELY ACCEPTED MECHANISM IS THE --- --- THEORY BASED ON DISSOLUTION OF PLASTER AND INSTANT RECRYSTALLIZATION OF GYPSUM, FOLLOWED BY INTERLOCKING OF THE CRYSTALS TO FORM THE SET SOLID
DISSOLUTION PRECIPITATION
45
THE SETTING REACTION OF GYPSUM OCCURS BY: (4)
DISSOLUTION OF CALCIUM SULFATE HEMIHYDRATE FORMATION OF A SATURATED SOLUTION OF CALCIUM SULFATE AGGREGATION OF LESS SOLUBLE CALCIUM SULFATE DIHYDRATE, AND PRECIPITATION OF THE DIHYDRATE CRYSTALS.
46
THE -- RATIO IS AN IMPORTANT FACTOR IN DETERMINING THE PHYSICAL AND CHEMICAL PROPERTIES OF THE FINAL GYPSUM PRODUCT.
W/P
47
``` Mixing time (MT)  ```
DEFINED AS THE TIME FROM THE ADDITION OF THE POWDER TO THE WATER UNTIL THE MIXING IS COMPLETED.
48
MECHANICAL MIXING OF STONES AND PLASTERS | IS USUALLY COMPLETED IN
20 TO 30 SEC.
49
HAND-SPATULATION GENERALLY REQUIRES AT | LEAST --- TO OBTAIN A SMOOTH MIX.
A MINUTE
50
WORKING TIME (WT)
WORKING TIME IS THE TIME AVAILABLE TO USE A WORKABLE MIX, ONE THAT MAINTAINS A UNIFORM CONSISTENCY TO PERFORM ONE OR MORE TASKS.
51
SETTING TIME (ST)
THE TIME THAT ELAPSES FROM THE BEGINNING OF MIXING | UNTIL THE MATERIAL HARDENS
52
PROBABLY THE MOST EFFECTIVE AND PRACTICAL METHOD FOR | CONTROLLING THE SETTING TIME IS THE
ADDITION OF CERTAIN CHEMICAL MODIFIERS TO THE MIXTURE OF PLASTER OR DENTAL STONE.
53
IF THE CHEMICAL ADDED DECREASES THE SETTING TIME, IT IS KNOWN AS AN---; IF IT INCREASES THE SETTING TIME, IT IS KNOWN AS A ---
accelerator | retarder
54
THE CRYSTALLIZATION PROCESS IS PICTURED AS AN
OUTGROWTH OF CRYSTALS FROM NUCLEI OF CRYSTALLIZATION. ON THE BASIS OF THE ENTANGLEMENT OF THE DIHYDRATE CRYSTALS, CRYSTALS GROWING FROM THE NUCLEI CAN INTERMESH WITH AND OBSTRUCT THE GROWTH OF ADJACENT CRYSTALS.
55
WHEN SUFFICIENT CRYSTALS FORM TO PRODUCE THE | OUTWARD THRUST BY IMPINGEMENT,
SETTING EXPANSION | FOLLOWS
56
SOMETIMES A SETTING EXPANSION IS ADVANTAGEOUS FOR A DENTAL PROCEDURE; SOMETIMES IT IS DISADVANTAGEOUS, BECAUSE IT MAY BE A SOURCE OF ---.
ERROR
57
SETTING EXPANSION MUST BE CONTROLLED TO OBTAIN THE | DESIRED --- IN DENTAL APPLICATIONS.
ACCURACY
58
THE MOST EFFECTIVE METHOD FOR CONTROLLING THE SETTING EXPANSION IS THROUGH THE ADDITION OF CHEMICALS BY THE MANUFACTURER. THE SETTING EXPANSION CAN BE REDUCED BY ADDING EITHER (3)
POTASSIUM SULFATE, SODIUM CHLORIDE, | OR BORAX.
59
IMPRESSION PLASTER (TYPE I) (2)
COMPOSED OF PLASTER OF PARIS, TO WHICH MODIFIERS HAVE BEEN ADDED TO REGULATE THE SETTING TIME AND THE SETTING EXPANSION. RARELY USED ANYMORE FOR DENTAL IMPRESSIONS.
60
MODEL PLASTER (TYPE II) (2)
IT IS USUALLY MARKETED IN THE NATURAL WHITE COLOR, THUS CONTRASTING WITH STONES THAT ARE GENERALLY COLORED. TYPE II MODEL PLASTER IS RELATIVELY WEAK AS EVIDENCED BY A COMPRESSIVE STRENGTH AS LOW AS 9 MPA AND A TENSILE STRENGTH OF 0.6 MPA.
61
DENTAL STONE (TYPE III)
TYPE III STONES ARE PREFERRED FOR CASTS USED TO PROCESS DENTURES, BECAUSE THE STONE HAS ADEQUATE STRENGTH FOR THAT PURPOSE AND THE DENTURE IS EASIER TO REMOVE AFTER PROCESSING.
62
DENTAL STONE, HIGH STRENGTH (TYPE IV)
 A HARD SURFACE IS NECESSARY FOR A DIE STONE, BECAUSE THE CAVITY PREPARATION IS FILLED WITH WAX THAT IS CARVED FLUSH WITH THE MARGINS OF THE DIE.
63
DENTAL STONE, HIGH STRENGTH, HIGH EXPANSION (TYPE V)
THE TYPE V DENTAL STONE GYPSUM PRODUCT EXHIBITS AN EVEN HIGHER COMPRESSIVE STRENGTH THAN DOES THE TYPE IV DENTAL STONE.
64
THE SETTING EXPANSION HAS BEEN INCREASED FROM A MAXIMUM OF (TYPE V)
0.10% TO 0.30%.
65
THE RATIONALE FOR THE INCREASE IN SETTING EXPANSION | LIMITS IS THAT
CERTAIN NEWER ALLOYS, SUCH AS BASE METAL, HAVE A GREATER CASTING SHRINKAGE THAN DO THE TRADITIONAL NOBLE METAL ALLOYS. THUS HIGHER EXPANSION IS REQUIRED IN THE STONE USED FOR THE DIE TO AID IN COMPENSATING FOR THE ALLOY SOLIDIFICATION SHRINKAGE.
66
Maximum | Intercuspation
All the teeth contact in a stable way
67
Centric Occlusion | Contact:
First contact when leaf gauge is in place on the anterior teeth
68
CR: Condyle in the most --- position
anterior-superior

Occlusion (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions