Surveying and denture design Flashcards
instrument used to analyse tissue undercuts and determine path of insertion
analysing rod
instrument used to scribe tooth and tissue undercuts on model
graphite model
instrument for measuring desired amount of undercut for clasp material used
undercut gauge
instrument used to trim the blocked out undercut areas on model
the chisel
what clasp can be used for a diagonal survey line?
occlusally approaching clasp
what clasp can be used for a high survey line?
gingivally approaching T bar
what clasp can be used for a low survey line?
gingivally approaching I bar
what depth of undercut can a CoCr utilise?
0.25mm
what depth of undercut can SS utilise?
0.5mm
what depth of undercut can gold clasp utilise?
0.75mm
what is the most brittle material of clasp?
cocr
what are the 3 functions of occlusal rests?
support
direct occlusal loads down long axis of tooth
indirect retention
what thickness is required for a PMMA plate?
1.5-2mm
what thickness is required for cocr plate?
0.5mm
what depth is required from sulcus to gingival margin to prescribe a lingual bar?
7mm
what does the 7mm sulcus depth allow for a lingual bar?
3.5mm bar width
3.5mm clearance from gingival margin
what can be added to a lingual bar to resist posterior uplift (indirect retention)?
cummer arms
what is a requirement for a dental bar?
no spacing between anterior teeth
minimum crown height of 9mm
what does 9mm crown height allow with a dental bar?
bar width 5mm
2mm clearance from gingival margin
2mm clearance from incisal tip
list types of cocr clasps
ring clasp
occlusally approaching
3 arm
what type of clasp can engage deeper undercuts than metal clasps?
dental d acetyl resin clasp
variations of gingivally approaching clasps
T
I bar
dimension requirements for mid palatal bar, post bar or ant bar?
width between 7-12mm
what are undercut areas on the cast filled with?
plaster
why are undercut areas on casts filled with plaster?
so PMMA cant enter undercuts
