RP - surveying and design

Question 1

what is used to analyse tooth and tissue undercuts and determine the path of insertion?

Answer 1

analysing rod

Question 2

what is used to scribe tooth and tissue undercuts on the model with the graphite marker?

Answer 2

graphite marker

Question 3

what is used to measure the desired amount of undercut for the clasp material used?

Answer 3

undercut gauge

Question 4

what is used to trim the blocked out undercut areas on the model?

Answer 4

chisel

Question 5

what information is gained from the survey line?

Answer 5

indicates the undercut area on tooth and non undercut area
the type of survey line indicated what retentive component can be used to help retain the denture

Question 6

what type of clasp would be used for a diagonal survey line?

Answer 6

occlusally approaching clasp
(ss or cocr)

Question 7

what type of clasp would be used for a high survey line?

Answer 7

gingivally approaching clasp

Question 8

what type of clasp would be used for a low survey line?

Answer 8

gingivally approaching clasp - mesial, central or distal positioned.

Question 9

what material of clasp is used for an undercut of up to 0.25mm?

Answer 9

cocr (brittle)

Question 10

what material of clasp is used for an undercut of up to 0.5mm?

Answer 10

ss (more flexible, so can engage deeper undercut)

Question 11

what material of clasp is used for an undercut of up to 0.75mm?

Answer 11

gold - most flexible

Question 12

what are the 2 parts of a clasp?

Answer 12

bracing area
flexible tip

Question 13

what are the 3 functions of occlusal rests?

Answer 13

provide support
direct occlusal loads down long axis of tooth
provide indirect retention

Question 14

how thin is a cocr plate?

Answer 14

0.5mm

Question 15

how thick is PMMA for a denture base?

Answer 15

1.5-2mm

Question 16

how much space is required from the sulcus depth to the gingival margin to prescribe a lingual bar?

Answer 16

7mm

allows for 3.5mm bar width and 3.5mm clearance from gingival margin

Question 17

how thick should a lingual bar be?

Answer 17

3.5mm

Question 18

what can be added to a lingual bar to add indirect retention?

Answer 18

cummer arms

Question 19

when is it a good idea to prescribe a lingual bar?

Answer 19

spaced anteriors

Question 20

how much crown height is required for a dental bar?

Answer 20

9mm

bar width 5mm
2mm clearance from gingival margin
2mm clearance from incisal tip

Question 21

what is more hygienic? lingual bar or dental bar?

Answer 21

dental bar - frees up the gingival margins and lingual mucosa

Question 22

list the different designs of clasps used to retain dentures?

Answer 22

• cocr ring clasp with occlusal rest
• occlusally approaching circumferential clasp, cocr with occlusal rest
• 3 arm clasp cocr with occlusal rest
• ss occlusally approaching
• gold gingivally approaching clasp
• dental.d.acetyl resin clasp

Question 23

advantages of dental.d.acetyl resin clasps?

Answer 23

very flexible
can engage deeper undercuts than metal clasps
available in tooth shades

Question 24

what are the variations of gingivally approaching clasps?

Answer 24

roach T or T clasp
I bar clasp

Question 25

what are the dimension requirements for a mid palatal bar, posterior bar or anterior bar?

Answer 25

bar width 7-12mm