Taking the primary impressions Flashcards
What is the retromolar pad and what is the pear shaped pad?
What areas need to be captured in the mandibular impression? - buccal side
retromolar pad
pear shaped pad
buccal shelf
frenum attachments
What areas need to be captured in the mandibular impression? - lingual side
Full depth of the sulcus to the floor of the mouth
capturing the mylohyoid ridges
lingual frenum attachment
What is the lingual frenum attachment?
connects the tongue to FOM
MYLOHYOID RIDGE?
What are the important features to capture in the maxillary arch impression?
post amp area - from hamular notch to hamular notch
Should extend forward to the midline fovea
distobuccal folds behind last standing molars
rugae
What is the point of perforations in plastic trays?
retention of material
What do metal trays have to allow retention of material?
rim lock undercut periphery
What do you want the mandibular and maxillary trays to avoid hitting at the bad?
mandibular impression = don’t want tray to hit ramus
maxillary impression = coronoid process
Do you get the pt to move their mandible when taking maxillary impressions?
yes
left to right
capture where the coronoid process is coming in
What do place on the plastic tray before impression material added?
impression tray adhesive
What is being mixed for impressions here?
silicon putty
When you are taking a lower impression, do you get the pt to move their tongue?
yes…
up, down, left , right and forwards
The dentulous areas have not had any silicon putty, why is this?
shows muscle attachments
allow the saddle areas to better support a denture base under functional load
Is any more silicon putty added after this has been taken?
yes, add more silicon putty
sulcus depth, muscle attachments and free end saddle during natural mouth movements
fully capture all the surrounding anatomy
What is being cut away here?
areas with undercuts
would interfere with taking impression of hard tissue areas
When you have your silicon putty trimmed and muscle attachments etc have been captured, what do you do next?
apply alginate
take impression
What are the stages after taking the impression?
rinse
disinfect and wrap in damp paper towel
prescribe for lab to cast up and articulate
What other information do you send to the lab along with the impression?
wax registration paste
wax squash bite
If you do not have posterior teeth (as shown) lab will need to make light cured acrylic based bite registration blocks
you will then use them to register pts bite
