9/19 - Prosthodontic Procedures: Implant Impressions Flashcards
how many tabs are on the implant interface and pick-up interface of self-guiding impression copings
7 tabs
what is the purpose of implant impressions
- capture 3D position of implant in relation to adjacent teeth and soft tissue
- fabrication of implant restoration
impression copings are specific to what
diameter of implant
what are the different types of impression copings
transfer (closed tray) and pick-up (open tray)
are transfer/closed tray impression copings fixture level impressions
YES
what impression coping remains in mouth when impression material is removed
transfer (closed-tray)
what impression coping needs to be removed, attached to replica, and is repositioned into impression
transfer (closed tray)
how do transfer/closed tray impression copings introduce error
- hyperocclusion
- misfit of abutment/crown
indications for transfer/closed tray impression copings
- individual implant restorations
- limited vertical opening/access
are pick-up/open tray impression copings fixture level impressions
YES
what impression requires a hole made in tray to access and unscrew guide pin prior to removal of impression
pick-up (open tray)
what impression coping is removed from mouth with impression
pick-up (open tray)
which impression tray has improved accuracy
pick-up (open tray)
indications for pick-up (open tray)
- custom impression coping
- multiple implants
- full arch implant cases
examples of implant cases that indicate need for pick-up (open tray)
- splinted restorations/implant FDPs
- converging/diverging implants
you should request implant impression components ___ week(s) prior to appointment
at least one week
T/F: throat packs are dumb and aren’t needed when creating implant impressions
FALSE! need
is it okay if you work slowly when removing healing abutments and then taking impressions?
NO! don’t want to let the tissue collapse
what do you do with CHX when creating implant impressions
- irrigate sulcus w/ mono jet syringe
- cleanse healing abutments
how do you know when closed tray impression coping is in?
feel it ‘drop in’ and engage slots/tabs
do you hand tighten or use hand piece to place closed tray impression copings
hand tighten
when taking radiographs of impression coping, what must be present in pic
- confirmation of components seated
- clear, sharp threads
- x-ray beam parallel to implant (BW)
- do not need apex, just need connection and crestal bone
which is acceptable, which is unacceptable?
top = unacceptable
bottom = acceptable
what do you place in the hex portion of implant impressions
red rope wax in hex
light body PVS goes where? medium body PVS goes where?
light body turquoise -> gingival
medium body purple -> custom tray
once you remove impression copings and place healing abutments back on implants by hand tightening in patient, can the patient be dismissed?
YES
T/F: healing abutments should be tightened with a hand piece
FALSE! HAND TIGHTEN ONLY
how should implant impression closed tray be repositioned into impression
spline should be in line
what happens if spline is not aligned in closed tray
30 degree misfit/shift of abutment and crown will not sit
what happens if you don’t seat impression coping fully back into impression
hyperocclusion of implant restoration
what is the purpose of custom impression copings
- make an impresion coping that replicates cervical contoours
- communicates with lab tech (final custom abutment contours, soft tissue support simlar to provisional)
what impression coping is used for custom impression copings
pick-up (open-tray)
when creating custom impression coping, do you place the PVS around provisional in patient’s mouth or on cast?
on cast
once PVS is set around custom impression coping, what do you do?
unscrew abutment and leave PVS material in then place open tray impression coping with hex driver
once open tray impression coping is placed back into the hard rock cast without the provisional, what do you do? why
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
after composite is placed into provisional PVS impression, what do you do?
cure! make sure composite is not bonded to adjacent teeth
what can you place in your custom tray to help guide where you drill your hole for open tray coping
red wax
is adhesive needed in custom tray
yes
do you unscrew the open tray impression coping BEFORE or AFTER removing custom tray?
BEFORE REMOVAL
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
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
what stone do you use for implant master cast
HARD STONE
before you remove the custom tray from the hard stone, what must you do?
remove anterior pin w/ open tray with hex