RPD Lecture 1

Question 1

what is the most common reason for PRDP?

Answer 1

age factor! usually posteriors go first

Question 2

is the proportion of edentulous adults in the US increasing or decreasing?

Answer 2

decreasing for sure…
13% of the population in the US is 65 % or older. this number is expected to double by 2030
**so this means that the projected unmet needs for FDPs, PRDPs and implants will increase between 2005 and 2020

Question 3

what is the metal framework composed of?

Answer 3

cobalt chrome

Question 4

what is the purpose of the reciprocal arm?

Answer 4

it’s for support and stability

Question 5

what is the kennedy classification of partially edentulous arches based on?

Answer 5

the frequency of observation in a patient population

and the suggested design principles.

Question 6

describe kennedy class I

Answer 6

it’s a BILATERAL edentulous located posterior to the natural teeth
MOST COMMON

Question 7

describe class Kennedy Class II?

Answer 7

it’s a unilateral edentulous area located posterior to the remaining teeth

Question 8

describe kennedy class III?

Answer 8

a unilateral edentulous area with natural teeth ANTERIOR and POSTERIOR to it

Question 9

this class is bound on BOTH sides by abutment teeth?

Answer 9

class III

Question 10

describe kennedy class IV?

Answer 10

a single, bilateral (crosses midline) edentulous area located ANTERIOR to the remaining teeth

Question 11

what are class IV generally caused by?

Answer 11

trauma.
*must cross midline to be a class IV
anteriors

Question 12

what dicates the path of insertion for removable?

Answer 12

the TEETH

external surfaces of the teeth and their relationship (parallelism to each other)

Question 13

what is the INFRABULGE?

Answer 13

that’s what is apical to the survey line-

that’s where we place the RETAINING cusp to resist VERTICAL displacement.

Question 14

infrabulge resists what?

Answer 14

vertical displacement.

it’s for retention

Question 15

does the supra bulge help with retention?

Answer 15

no, just to brace to tooth

Question 16

what kind of forces does the supra bulge resist?

Answer 16

lateral stresses on abutment tooth

Question 17

frictional forces that increase the PRDP retention, help control stress, and define the path of insertion?

Answer 17

guide plane/plates

Question 18

because these have destrutvie potential during rotation of the PRDP, in most cases, use them sparingly to reduce stress?

Answer 18

claps

Question 19

what’s the most favored clasp position?

Answer 19

quadrilateral- super stress reducer.

all occlusal forces are supported by the abutment teeth.

Question 20

what classifications allow to use quadrilateral support?

Answer 20

Kennedy III and IV

Question 21

chewing efficiency of quadrilateral?

Answer 21

30%

Question 22

what class is associated with Kennedy II?

Answer 22

tripod.

place cusps on dentate side as far away as possible.

Question 23

what is the worst clasp position?

Answer 23

bilateral.
unavoidalbe in conventional PRDP design.
use for Kennedy I mods/no mods

Question 24

what kind of undercut to most retentive clasps use?

Answer 24

.01 undercut apical to the survey line

Question 25

resistance to displacement towards teeth and soft tissue

Answer 25

support

Question 26

resistance to displacement in a mediolateral or anteroposterior direction.

Answer 26

stability

Question 27

what does occlusion depend on?

Answer 27

the type (canine protected, group function, or bilaterally balanced) depends on the opposing occlusion

Question 28

what is the purpose of surveying?

Answer 28

it determines what tooth mods will be needed to facilitate the design USES surveyor and the DIAGNOSTIC casts

Question 29

what is the instrument called that measures the path of insertion with the surveyor?

Answer 29

the STYLUS

Question 30

what does the PATH of placement identify?

Answer 30

it will eliminate or minimize interference upon insertion and removal. it will identify interferences that cannot be eliminated or minimized without corrective action

Question 31

are ALL proximal surfaces adjacent to the edentulous spaces involved in path of placement?

Answer 31

yes, IN GENERAL

Question 32

where the horizontal disc meets the tooth surface and the barrel is tangent to the survey line?

Answer 32

that's the .01 mid facial undercut

Question 33

what is TRIPODING or INDEXING?

Answer 33

this si to record the cast position in relation to the path of insertion. So that we can see this anywhere in the world? **3 points is the most stable

Question 34

what are advantages of using Kennedy's classes?

Answer 34

- immediate visualization of the arch - distingushies between tooth and tooth/soft tissue supported PRDPs. - permits a logical approach to design.

Question 35

RULE 1 APPELLATE | do you classify before or after extraction?

Answer 35

after duh.

Question 36

if a third molar is missing, is it considered in the classification?

Answer 36

NOPE

Question 37

if a third molar is PRESENT and to be used as an abutment, do we consider it/

Answer 37

makes sense-duh

Question 38

what happens if a second molar is missing and not to be replaced?

Answer 38

don't include it

Question 39

what is RULE 5!?!? of applegate

Answer 39

the most POSTERIOR edentulous area or areas always determines the classification

Question 40

what do you call edentulous areas other than those determining the classification?

Answer 40

those are MODIFICAITONS and designated by the absolute number observed. *Class II with 2 mod spaces*

Question 41

is the extent of the modification considered?

Answer 41

NO, just the absolute number of additional edentulous areas.

Question 42

What class Kennedy has no mods?

Answer 42

``` class IV because of rule 5? the posterior rule? ```

Question 43

do the mods change depending on how many teeth missing?

Answer 43

nope

Question 44

what does length os span have to do with abutment teeth force?

Answer 44

the greater the edentulous span, the greater to force to the abutment teeth

Question 45

what is the best Ridge shape?

Answer 45

inverted U | size = you want large in height and width

Question 46

what determines the clasp and stress?

Answer 46

so with clasps, the longer and more flexible= less stress

Question 47

what metals are more rigid than gold?

Answer 47

base metals.