Access Prep Flashcards
definition of access cavity
The opening prepared in a tooth to gain entrance to the pulp canal system for the purpose of cleaning, shaping, and obturating
occlusal clearance of posterior teeth
reduce occlusion by 1-2mm
produce flat surface for reproducable reference point
*only for posterior teeth
if there is an existing bridge or crown on posterior teeth?
do NOT reduce the occlusal plane
access cavity objectives
removal of pulp chamber roof removal of pulp stones locating of all canals straight line access to every canal divergent smooth walls preservation of structural integrity of the tooth
shape of walls in access prep and reason
parallel or slightly divergent walls to allow better light and visibilty and hold restoration
access cavity knowledge requires
- root canal morphology
- access cavity outline shape
- depth of preparation
- long axis of the tooth
most teeth have what inclination?
mesial inclination
maxillary 1st molar access prep details
shape details, root morphology, pulp chamber details?
Rhomboid-shape access
3 roots
*MB root has a second canal in 95.2% of the time
Pulp chamber is closer to the mesial
straight line access
have to remove cervical dentin overhang - like creating the ‘flare’
mandibular 1st and 2nd molar access prep details
shape details, root morphology, pulp chamber details?
FIRST: Rhomboid outline
fourth canal in 33%
SECOND: same as first, less common two distal canals (4%)
C-shaped configuration in 4-7.6%
Maxillary 1st pre-molar
access prep details
shape details, root morphology, pulp chamber details?
TWO Canals in 69% - two roots
Ovoid outline
Mandibular 1st pre-molar
access prep details
shape details, root morphology, pulp chamber details?
70
pre-treatment objectives
- evaluation of existing restoration
- removal of existing restoration
- removal of all caries
- evaluate restorability
- occlusal clearance of posterior teeth
