RPD Design I

Question 1

minimal tissue/tooth coverage is achieved via

Answer 1

Major connector with open design

avoiding plating teeth

Question 2

each RPD component must ____

Answer 2

have a function

Question 3

five big general design principles

Answer 3

1. Keep it simple
2. Maintain symmetry
3. incorporate essential elements into the design
   (retention guidance support stabilization)
4. Incorporate essential elements in each direct retainer
5. Widely distribute design elements around the arch
6. Avoid placing framework on occlusal contact areas
7. consider likelihood of tooth loss

Question 4

Retention elements

Answer 4

1. direct retainer engaging the undercut
2. friction from guide planes
3. physical retention form denture base

Question 5

C+1 rule

Answer 5

RPD needs Kennedy Class # + 1 = # of clasps needed

Question 6

exception to C+1 rule

Answer 6

• Class IVs

- Class II w/out modification= only 2 clasps

Question 7

Support is from

Answer 7

1. primary rests
2. auxilary rests (indirect retainers)
3. denture base (for distal extensions)
4. RPD components above the survey line
5. some maxillary major connectors

Question 8

guidance/stabilization is from

Answer 8

1. including opposing surfaces

2. placed on many teeth

Question 9

support for aker’s arm is from

Answer 9

1. ⅓ of retentive arm that’s above the survey line
2. rest
3. reciprocal arm

Question 10

for questionable prognosis teeth use mandibular bar or plate?

Answer 10

plate- allows for adding teeth

Question 11

select ___ retainer in anterior abutment of a tooth supported area

Answer 11

stress releasing

Question 12

presence of a fulcrum line determines:

Answer 12

• choice and design of direct retainer (ie. stress releasing_
• requirement of an indirect retainer

Question 13

nature of tissue support determines

Answer 13

• type of denture base

- need for future reline

Question 14

esthetic consideration determines

Answer 14

anterior clasp design

Question 15

steps for RPD design

Answer 15

1. review diagnostic date
2. survey diagnostic cast
3. formulate RPD design
4. draw design on cast (diagnostic then surveyed cast) and lab Rx

Question 16

review diagnostic data for

Answer 16

• quality of soft tissue support
• quality of perio support for remaining teeth (C/R ratio)
• examine mounted diagnostic cast for occlusal scheme, centric contact and inter-occlusal space.

Question 17

survey diagnostic casts orders

Answer 17

• survey duplicate of diagnostic cast
• survey duplicate of definitive cast (after fixed prostheses were delivered)
• survey both teeth and tissue

Question 18

determining the RPD design sequence

Answer 18

1. select ideal major connector
2. identify axis of rotation for class 1 and 2
3. determine teeth for direct retainer
4. determine teeth for indirect retainer (class 1 and 2)
5. determine teeth for auxiliary rest
   6 determine specific direct retainer types

Question 19

determining factors for selecting major connectors

Answer 19

• maxillary arch classification
• mandibular floor of the mouth depth
• arch configuration (teeth missing or no)
• anatomical factors (ie. tori)
• perio condition of remaining teeth
• quality of soft tissue

Question 20

at some point make a flash cards for the summary of major connectors on slides 21 and 22

Answer 20

ss

Question 21

in max arch, the border of major connector should be at least ___ mm form FGM.. otherwise ___

Answer 21

in max arch, the border of major connector should be at least 6 mm form FGM.. otherwise plate teeth

Question 22

in mandibular arch, the border of major connector should be at least ___ mm form FGM.. otherwise ___

Answer 22

in mandibular arch, the border of major connector should be at least 3 mm form FGM.. otherwise plate teeth

Question 23

border of the major connector should run ____ to the gingival margins

Answer 23

parallel

Question 24

for class 1 put one clasp on each____

Answer 24

terminal abutment

Question 25

determining teeth for indirect retainers

Answer 25

- teeth located as far from the fulcrum line as possible - indirect retainer should be perpendicular to the fulcrum line - usually an auxiliary rest - most commonly on canines or first premolars - avoid incisors - class 1s usually require two indirect retainers

Question 26

teeth for auxiliary rests

Answer 26

- put on abutments next to edentulous areas that don't have direct retainers - put on long segments of major connector that doesn't have a direct retainer - on each end of anterior segment of mandibular lingual plate

Question 27

determination of specific direct retainer types

Answer 27

- location and amount of tooth undercuts - presence and location of soft tissue interference when selecting infra-bulge clasps - tooth condition (existing restorations) - occlusal contact - esthetic consideration

Question 28

steps for drawing an RPD design

Answer 28

1. draw all rests (primary, indirect, auxiliary) 2. draw direct retainer 3. locate and draw all acrylic resin retention elements 4. draw major connector outline 5. draw minor connectors to connect all unattached components 6. finish drawing major connector

Question 29

``` for class III fulcrum= indirect retainer= use ___ direct retainers impression method is ___ denture base is ___ ```

Answer 29

``` fulcrum= nonexistent indirect retainer=nonexistent use simple direct retainers impression method is less critical denture base is not critical (short=metal, long=combined) ```

Question 30

mandibular lingual bar vs. plate

Answer 30

bar is best... pts. like it | plate is used more bc there are more indications

Question 31

CC = ""

Answer 31

"Aker" "Simple Clasp"

Question 32

primary direct retainers for class III

Answer 32

CC or infrabulge

Question 33

class III special situation (undercut location) clasps

Answer 33

embrasure clasp ring clasp hairpin clasp

Question 34

cast circumfrential clasps disadvantage

Answer 34

non stress breaking poor esthetic could create occlusal interference limited adjustability

Question 35

infrabulge clasp indications

Answer 35

``` esthetic conserns class II or II survey line, when akers is not indicate ```

Question 36

invrabulge clasp advantage

Answer 36

good esthetics | minimal tooth coverage

Question 37

Infra bulge clasp design

Answer 37

- I bar - must keep distal rest and reciprocal arm - approach tooth starting 4mm away from FGM - cross FGM at 90deg angle - reciprocal arm is similar to CC

Question 38

infrabulge contraindications

Answer 38

- inadequate vestibular depth - deep soft/hard tissue undercuts - high frenum attachment

Question 39

ring clasps indication

Answer 39

``` medially tipped isolated molars class II survey line ```

Question 40

ring clasp disadvantage

Answer 40

extensive tooth coverage

Question 41

hairpin clasps indications

Answer 41

class II survey line

Question 42

hair pin clasp disadvantage

Answer 42

extensive tooth coverage | food trap!!!

Question 43

embrasure clasps indication

Answer 43

tooth supported without a mod space | extremely narrow mod space

Question 44

embrasure clasp disadvantages

Answer 44

extensive tooth coverage extensive tooth modification retainer/rests not widely spread

Question 45

class 1 survey line use: posterior = anterior=

Answer 45

``` class 1 survey line use: posterior =CC anterior= I bar ```

Question 46

class II survey line use: posterior = anterior=

Answer 46

``` class 2 survey line use: posterior =ring or hairpin anterior=mod. T or T clasp ```

Question 47

``` class III survey line use: posterior = tooth modification surveyed crown anterior= I bar ```

Answer 47

``` class III survey line use: posterior = tooth modification surveyed crown anterior= I bar ```

Question 48

palatal strap design requirement = indication= contraindication=

Answer 48

``` design requirement = at least 1mm thick and 8mm wide indication=short span class III contraindication= large tori ```

Question 49

palatal bar design requirement = indication= contraindication=

Answer 49

``` design requirement = 2-3mm thick indication= very short span class III contraindication=mesial to 2nd pmolar ```

Question 50

AP Strap design requirement = indication= contraindication=

Answer 50

``` design requirement = less than 1mm thick at least 8mm wide anterior terminate at anterior abutment in rug valley posterior terminates at vibrating line ``` ``` indication= class 1 with less ideal support few remaining teeth inadequate retainer compromised anterior ```

Question 51

Palatal strap design requirement = indication= contraindication=

Answer 51

``` design requirement = less than 1mm thick partial or full coverage variable anterior termination posterior terminates at vibrating line ``` ``` indication= class 1 with less than ideal support few remaining teeth inadequate retainer compromised anterior ```

Question 52

U shaped design requirement = indication= contraindication=

Answer 52

``` design requirement = more than 1mm thick terminate at the junction of vertical ridge and horizontal plate indication= inoperable tori gaging patient ``` contraindication= avoid if possible lacks rigity

Question 53

lingual bar design requirement = indication= contraindication=

Answer 53

design requirement = 5mm tall x 2.5 mm thick half pear shape at least 3mm from gingival margin indication= 8mm depth of floor of the mouth first choice for major connection contraindication= lingual plate indication

Question 54

lingual plate design requirement = indication= contraindication=

Answer 54

``` design requirement = covers cingulum up to proximal contact supported by rest on both sid lingual plate only distal posterior abutment indication= insufficient vest depth compromised anterior teeth missing anterior teeth furure anterior tooth loss not ideal support most frequently used monor lingual tori ```