Fundamentals of RPD Design Flashcards
which kennedy classification cannot have a modification space?
four
tooth tissue supported (2)
kennedy class 1
kennedy class 2
tooth supported (2)
kennedy class 3
kennedy class 4 (single edentulous area crossing the midline)
whats next (4)
survey the cast and draw/carve orientation (tripod) lines
draw heights of contour
evaluate possible guide planes
identify undercuts
what is opposing (2)
natural teeth or denture
super erupted teeth
lets take this info and make an RPD (6)
Major Connectors
* Minor Connectors
* Rests
* Retentive Clasps
* Reciprocal clasps/plates
* Indirect retainers
mandibular RPD major connectors (2)
lingual plate
lingual bar
5 reasons to lingual plate
- Opposing a maxillary denture
- Inadequate space for a bar (8mm needed)
- Anticipate loss of additional teeth
- Mandibular tori
- Aid in lateral and rotational stability
maxillary major connectors (4)
palatal strap
AP strap
anterior palatal strap
full palatal coverage
if the major connector is not plating the lingual surfaces of the max teeth the frame needs to be at least
6 mm away from the gingival margin
minor connectors
portion of the RPD framework that connects the major connector to
-the clasp assembly
-indirect retainer
-denture base
in a kennedy class 3 RPD the rests of the RPD are located….
A. Away from the edentulous area on the on the teeth adjacent to the edentulous area
B. Toward the edentulous area on the teeth adjacent to the edentulous area
C. As far away from the edentulous area as possible
D. Rest seats should not be located on the teeth next to the edentulous area.
RPD Rests
* Need approx – mm of inter-occlusal clearance
* – the buccal/lingual width
* Edentulous area bordered by teeth on anterior and posterior
- Rests located — the edentulous space
* Free end distal extension
- Rest located — from the edentulous area
1.5
1/3
toward
away
How many retentive clasps would typically be utilized in a kennedy class 1 RPD design?2
3
4
5
Number of clasps Necessary (4)
1: 2 clasps
2: 3 clasps
3 & 4: 4 calsps
of clasps =
kennedy class + 1 with a max of 4 clasps
how to alter the retentiveness of a clasp? (6)
- Clasp length
- Clasp diameter
- Clasp taper
- ½ round or round
- Material
- Amount of undercut engaged
retentive clasps (2)
infrabuldge
suprabuldge
infrabuldge
(3)
suprabuldge
(2)
I bar clasp
T and 1/2 T clasp
Y clasp
cast circumferential clasp (1/2 round and round)
wrought wire (combination clasp)
Infrabuldge clasps
advantages (2)
contraindications (3)
esthetic
more retentive
- Excessive soft tissue undercut
- Lack of vestibular depth (min 4 mm)
- Inability to place the terminus at the gingival 1/3
infrabuldge clasps
best utilized on a sound abutment tooth adjacent to a free end edentulous area provided the tooth is tall enough and provides relief (undercut( gingival to the distal guide plate
suprabuldge clasps
* Circumferential
* 1/2 round or round cast
* Best utilized
* ½ round -
* round -
Tooth supported RPDs
Tooth/Tissue supported RPDs
Wrought Wire Clasps (Combination)
Best used on Tooth/Tissue Supported RPDs when the abutment tooth is compromised and an ideal guide plane is not present
THE REST SEAT IN THIS SENARIO WILL BE TOWARD THE FREE END DISTAL EXTENSION
what if i dont have any undercut (3)
surveyed crown
place a divot
place a composite