prep of the mouth and teeth for RPD definitive impressions

Question 1

what are the 4 stages in a restorative tx plan?

Answer 1

immediate tx
initial phase (hygienic or preparatory)
reconstructive (corrective) phase
maintenance

Question 2

what are the clinical stages of RPD construction?

Answer 2

primary impressions
primary jaw registration
mounted, surveyed study casts
design denture
tooth prep and definitive impressions
jaw registration
trial
delivery
review

Question 3

what may be included in mouth prep?

Answer 3

initial prosthetic tx
pre-prosthetic surgery
periodontal tx
orthodontic tx
fixes prosthodontic tx and endodontics
tooth prep

Question 4

what would be done in initial prosthetic tx?

Answer 4

repair and additions
temporary relines
occlusal adjustment
tx of denture stomatits

Question 5

what is pre-prosthetic surgery?

Answer 5

remove retained roots/unerupted teeth
remove pathology
improve contours of edentulous areas-by reducing bony prominences and hyperplastic soft tissue
eliminate prominent fraenal attachments

Question 6

what is periodontal tx?

Answer 6

establish health in periodontal tissues
assess px motivation
detailed instruction in oral hygiene procedures
scaling and root planing
periodontal surgery

Question 7

what is orthodontic tx ?

Answer 7

to optimise space
to optimise abutment alignment
cleft, hypodontia, perio px

Question 8

why is fixed prosthodontic tx used?

Answer 8

should follow denture design and precede denture construction
establishes clinical integrity of teeth before master impressions recorded
facilitates provision of crowns with guide planes rest seats etc.

Question 9

what is the purpose of tooth preparation?

Answer 9

provide rest seats
establish guide surfaces
modify unfavourable survey lines
create retentive areas

Question 10

what instrument is used to shape enamel surfaces?

Answer 10

rotary diamond instruments

Question 11

what is ideal rest seat prep?

Answer 11

produce favourable tooth surface for support
prevent interference w/ occlusion
reduce prominence of rest

Question 12

describe a maxillary anterior rest seat

Answer 12

a well-developed cingulum allows prep to stay w/i enamel

cylindrical diamond stone w/ rounded tip

Question 13

describe a mandibular anterior rest seat

Answer 13

lingual surface undeveloped cingulum - incisal rest seats used as cingulum will penetrate enamel

Question 14

what are the alternatives to rest seat prep?

Answer 14

produce rest seat in composite applied to cingulum area

bond a cast metal cingulum to tooth

Question 15

describe a posterior rest seat

Answer 15

reduce marginal ridge
saucer shaped to allow horizontal movement and dissipation of occlusal forces
rest at least 1mm thick

Question 16

what should be done if there is no space occlusally for a clasp to extend buccally from an occlusal rest?

Answer 16

prep must be extended as a channel on to the buccal surface

Question 17

what are guide planes?

Answer 17

2 or more parallel axial surfaces on abutment teeth, which limit the path of insertion of a denture, may occur naturally but prob need prepared

Question 18

what do guide planed provide?

Answer 18

increased stability
reciprocation
prevention of clasp deformation
improved appearance

Question 19

how are guide planes prepared?

Answer 19

tooth surfaces prepared to be parallel to each other and the path of insertion
extend vertically 3mm kept away from gingival margin
no more than 0.5mm enamel removed

Question 20

what would unfavourable survey lined cause?

Answer 20

clasp would be positioned too close to occlusal surface, causing occlusal interference -> px annoyance
deformation of clasp

Question 21

how are retentive areas created?

Answer 21

addition of acid-etched composite
broad area of attachment of restoration to enamel
ultrafine/hybrid composites

Question 22

what are the clinical stages of master impression?

Answer 22

obtain an accurate impression of the denture-bearing area
use individual tray
use an appropriate impression material

Question 23

what are the lab stages of master impressions?

Answer 23

produce casts
produce casting 
(if cobalt chrome)
produce record blocks
produce trial denture
produce finished denture

Question 24

what are individual trays?

Answer 24

made on primary casts from heat-cured or light cured acrylic
try in
adjust periphery as required

Question 25

what are the options for impression material?

Answer 25

alginate
polyvinylsiloxane
polyether
+ adhesive