9/19 - Prosthodontic Procedures: Implant Impressions

Question 1

how many tabs are on the implant interface and pick-up interface of self-guiding impression copings

Answer 1

7 tabs

Question 2

what is the purpose of implant impressions

Answer 2

1. capture 3D position of implant in relation to adjacent teeth and soft tissue
2. fabrication of implant restoration

Question 3

impression copings are specific to what

Answer 3

diameter of implant

Question 4

what are the different types of impression copings

Answer 4

transfer (closed tray) and pick-up (open tray)

Question 5

are transfer/closed tray impression copings fixture level impressions

Answer 5

YES

Question 6

what impression coping remains in mouth when impression material is removed

Answer 6

transfer (closed-tray)

Question 7

what impression coping needs to be removed, attached to replica, and is repositioned into impression

Answer 7

transfer (closed tray)

Question 8

how do transfer/closed tray impression copings introduce error

Answer 8

1. hyperocclusion
2. misfit of abutment/crown

Question 9

indications for transfer/closed tray impression copings

Answer 9

1. individual implant restorations
2. limited vertical opening/access

Question 10

are pick-up/open tray impression copings fixture level impressions

Answer 10

YES

Question 11

what impression requires a hole made in tray to access and unscrew guide pin prior to removal of impression

Answer 11

pick-up (open tray)

Question 12

what impression coping is removed from mouth with impression

Answer 12

pick-up (open tray)

Question 13

which impression tray has improved accuracy

Answer 13

pick-up (open tray)

Question 14

indications for pick-up (open tray)

Answer 14

1. custom impression coping
2. multiple implants
3. full arch implant cases

Question 15

examples of implant cases that indicate need for pick-up (open tray)

Answer 15

1. splinted restorations/implant FDPs
2. converging/diverging implants

Question 16

you should request implant impression components ___ week(s) prior to appointment

Answer 16

at least one week

Question 17

T/F: throat packs are dumb and aren’t needed when creating implant impressions

Answer 17

FALSE! need

Question 18

is it okay if you work slowly when removing healing abutments and then taking impressions?

Answer 18

NO! don’t want to let the tissue collapse

Question 19

what do you do with CHX when creating implant impressions

Answer 19

1. irrigate sulcus w/ mono jet syringe
2. cleanse healing abutments

Question 20

how do you know when closed tray impression coping is in?

Answer 20

feel it ‘drop in’ and engage slots/tabs

Question 21

do you hand tighten or use hand piece to place closed tray impression copings

Answer 21

hand tighten

Question 22

when taking radiographs of impression coping, what must be present in pic

Answer 22

1. confirmation of components seated
2. clear, sharp threads
3. x-ray beam parallel to implant (BW)
4. do not need apex, just need connection and crestal bone

Question 23

which is acceptable, which is unacceptable?

Answer 23

top = unacceptable
bottom = acceptable

Question 24

what do you place in the hex portion of implant impressions

Answer 24

red rope wax in hex

Question 25

light body PVS goes where? medium body PVS goes where?

Answer 25

light body turquoise -> gingival medium body purple -> custom tray

Question 26

once you remove impression copings and place healing abutments back on implants by hand tightening in patient, can the patient be dismissed?

Answer 26

YES

Question 27

T/F: healing abutments should be tightened with a hand piece

Answer 27

FALSE! HAND TIGHTEN ONLY

Question 28

how should implant impression closed tray be repositioned into impression

Answer 28

spline should be in line

Question 29

what happens if spline is not aligned in closed tray

Answer 29

30 degree misfit/shift of abutment and crown will not sit

Question 30

what happens if you don't seat impression coping fully back into impression

Answer 30

hyperocclusion of implant restoration

Question 31

what is the purpose of custom impression copings

Answer 31

1. make an impresion coping that replicates cervical contoours 2. communicates with lab tech (final custom abutment contours, soft tissue support simlar to provisional)

Question 32

what impression coping is used for custom impression copings

Answer 32

pick-up (open-tray)

Question 33

when creating custom impression coping, do you place the PVS around provisional in patient's mouth or on cast?

Answer 33

on cast

Question 34

once PVS is set around custom impression coping, what do you do?

Answer 34

unscrew abutment and leave PVS material in then place open tray impression coping with hex driver

Question 35

once open tray impression coping is placed back into the hard rock cast without the provisional, what do you do? why

Answer 35

space is filled with flowable composite so when placed in mouth, it puts pressure on the tissue the same way provisional did and tissue doesn't collapse

Question 36

after composite is placed into provisional PVS impression, what do you do?

Answer 36

cure! make sure composite is not bonded to adjacent teeth

Question 37

what can you place in your custom tray to help guide where you drill your hole for open tray coping

Answer 37

red wax

Question 38

is adhesive needed in custom tray

Answer 38

yes

Question 39

do you unscrew the open tray impression coping BEFORE or AFTER removing custom tray?

Answer 39

BEFORE REMOVAL

Question 40

once replicas are placed back onto the impression coping in custom tray w/ PVS, what do you place around the copings? what is this for

Answer 40

GINGIVAL MASK (resilient in nature) placed around interface of coping and impression material this is so that when you pour in stone, the two aren't locked together

Question 41

what stone do you use for implant master cast

Answer 41

HARD STONE

Question 42

before you remove the custom tray from the hard stone, what must you do?

Answer 42

remove anterior pin w/ open tray with hex