Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Removable Pros > L2-Impression and Impression Materials + Trays and Retention > Flashcards

L2-Impression and Impression Materials + Trays and Retention Flashcards

1
Q

Goal of impression

depends on…

A
  1. type of impression depends on..
  2. purpose of impression depends on…
  3. type of prostheis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what will tear easier… alginate or PVS?

A

alginate

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

Primary cast - purpose?

A

Support and Surface Area
DIAGNOSTIC
capture the SA and see what support we can get

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

T/F you can fabricate a denture on a primary cast

A

FALSE

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

Secondary cast - purpose?

A

RETENTION
can see more defined rugae and more accuracy here

make sure to have right type of trey and material

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

RETENTION is a function of what? (five)

A
  1. patient adaption
  2. polished surface contour
  3. atmospheric pressure
  4. adhesion
  5. cohesion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

adhesion and how to increase it

A

attraction of DIFFERENT molecules to each other - and increases by increasing SURFACE AREA

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

cohesion and how to increase it

A

attraction of the IDENTICAL molecules to each other - increase by increasing CONTACT (closeness)

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

atmospheric pressure

A

the pressure exerted on the denture by the air around it vs the LACK OF AIR inside the denture

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

is adhesion enough for denture retention?

A

NO - need the addition of cohesion

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

clinical significance of saliva-mucosa and attraction type?

A

adhesion

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

saliva-denture attraction is an example of?

A

adhesion

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

saliva-saliva attraction is an example of?

A

Cohesion attraction

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

what contributes to the suction formed by posterior palatal seal?

A

atmospheric pressure and by using mucodynamic capture of the folds by the final impression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

atmospheric border seal - clinical significance

A

the contact of the denture border with the underlying or adjacent tissues to prevent the passage of air or other substances

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

wash impression material?

A

VERY light bodied - barely signals on tissue and barely compresses the tissue so we can see detail of rugae and any other detail on the surface

this is a very low viscocity material

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

Muco-dynamic where? wht?

A

at the borders to create SUCTION

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

Muco-static where? why?

A

everywhere else

to limit resorption and increase cohesion

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

why cover as much surface area as possible?

A

to reduce movement and limit resorption and increase adhesion

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

muco-dynamic definition

A

selective displacing certain musculature and tissues of the oral cavity during an impression to force out air, changing the atmospheric pressure and create suction

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

muco-static definition

A

an impression taken without displacing any tissue - the mucosal tissues of the jaws as they are in a state of rest..

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

how do we (steps) for making impressions for edentulous?

A
  1. preliminary and final
  2. border molding and final impressions
  3. selective impressioning -
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

impression compound, ZOE paste and plaster are rigid or elastomeric?

A

rigid — NOT GOOD FOR UNDERCUTS

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

hydrocolloids, Polysulfide (rubber-base), silicones (PVS) and polyether are rigid or elastomeric?

A

elastomeric - GOOD FOR UNDERCUTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

impression compound is reversible or irreversible?

A

reversible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

impression compound used when?

A

for preliminary impressions - also alginate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

characteristics of compound impressions?

A 
mucodynamic 
more stable than alginate
better extension into vestibule folds 
can be removed before set (gagger)
can bead and box
inelastic
cost-low
28
Q

alginate is mucostatic for?

A

hard tissues

29
Q

alginate is muco-dynamic for?

A

soft tissue - heavy body

30
Q

can you bead and box alginate?

A

no- may deform under wight of stone if unsupported

31
Q

trays for preliminary impressions?

A

Must use edentulous trays if patient is edentulous because dentate stock trays will hold excessive alginate

32
Q

“Best” tray fit mindset?

A

may not be perfect - so adjust when need to with periphary wax
use periphary wax in areas that need more coverage or added material like to cover the RMP area or hamular notches

33
Q

general characteristics of final impressions

A

they are BOTH mucostatic and mucodynamic (so mucoselective)

34
Q

general final (2) impressions objective

A

Mucostatic detail (closeness= cohesion)
Diagnose denture
Mucodynamic (at the borders - and includes PPS)

35
Q

two types of material (general) that are required for final impressions

list the examples

A

Dynamic - at border
using compound and PVS - heavy bodied

Static (recording the interior tissues)
using light body polysulfide (rubber base)
PVS - Light and extra-light viscosity
ZOE (zinc oxide and eugoenol)

36
Q

Polyvinyl Siloxanes

A

Excellent surface details
;ight body PVS and XLV
static impression material - recording excellent tissue detail w/o compressing tissues

37
Q

characteristics of ZOE

A

most mucostatic
but are very sensative to moisture
are inelastic/rigid
irreversible but relinable

there are patient sensativity issues
also contraindicated if patient has exccess saliva or xerostomatic

38
Q

rubber base impressions are mucostatic if?

A

if they are light bodied

39
Q

tear energy between PVS and Rubber base?

A

PVS has MUCH HIGHER tear energy

40
Q

when is PVS contraindicated?

A

when patient has undercuts and large embrasures

41
Q

heavy body where?

A

borders - mucodynamic

42
Q

medium body where?

A

interior

43
Q

light or XL where?

A

intaglio - interior tissues - mucostatic detail

44
Q

impressions increase adhesion by?

cohesion by?

A

Adhesion by increasing surface area

cohesion by increasing closeness

45
Q

primary imperssion obkectives

A 
patient diagnosis
tissue outline 
preliminary casr
tray fabrication
adhesion
46
Q

secondary / final impression objectives

A
  1. denture diagnosis
  2. tissue detail
  3. final cast
  4. denture fabrication
    cohesion
47
Q

a well made custom tray?

A
  1. Fits closely to allow use of static impression materials
  2. relieved with wax depending on impression material used
  3. can be adapted at the borders to produce a dynamic seal (compound, PVS heavy)
  4. results from a great preliminary impression
48
Q

need tissue spacer when using PVS?

A

yes- PVS needs body in order to capture details without breaking apart

49
Q

custom trey is made from?

A

preliminary impression

50
Q

what do you use to make final impression (not material)

A

custom treys

51
Q

potential problomatic areas?

A

Anterior and Posterior undercuts

52
Q

where should you block out?

A

in the undercuts - we can increase closeness which will increase cohesion

53
Q

Effect on anterior blockout for anterior of tray

A
  1. maintains tissue contact
  2. maintains lip position
  3. maintains border seal

important the tray goes with path of insertion and maintains contact everywhere

54
Q

what do you do if anterior undercuts exist?

A

alter the path of insertion

if undercut - will need to position the tray up and back not just in and up

55
Q

what do you do if there are posterior undercts?

A
  1. alter the path

2. block out EVENLY

56
Q

corrective procedure for undercut in anterior only?

A

eliminate or decrease with TAIL DOWN TILT

57
Q

corrective procedure for undercut in posterior only?

A

eliminate or decrease with NOSE DOWN TILT IF NO ANTERIOR UNDERCUTS–anterior undercuts could increase with this if they exist OR block out evenly in posterior

58
Q

corrective procedure for undercut in anterior and posterior?

A
  1. eliminate or decrease anterior undercut 1st with TAIL DOWN TILT, then block out posterior undercuts evenly

so use the anterior as the new path and block out the posterior undercuts

59
Q

if patient has anterior and posterior undercuts will blocking out anterior work?

A

it could increase the posterior undercuts by doing tail down tilt (if dont block out posterior) and just change path of insertion

60
Q

adapt denture where and block out where?

A

adapt in anterior - to avoid too much thickness and blockout in the posterior

61
Q

posterior blockout compromises what?

A

loss of cohesion but not loss of esthetics

62
Q

tail down tilt

A

eliminates the anterior undercut

63
Q

nose down tilt

A

eliminates posterior undercut

64
Q

fabricating trey in SLC vs clinical?

A

clinical – all the way then cut 3mm from full depth of fold (with width remaining at 3mm) for clinical patient
SLC - went to the full depth and width of fold for SLC dentoform

65
Q

spacer and tissue stops for PVS? for PSR?

A

PVS - yes

PSR- no

Removable Pros (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions