Surveyed Crowns Flashcards
Dental Terminology
The advantages to the dental profession of a
successful effort in this direction are manifold. The
most important of these is that the use of a
uniform
terminology would permit authors to discuss their
concepts and techniques and be sure that these
would be understood by those who would read
the articles, regardless of the geographic location
or the specialty of the reader
What to Look For
(5)
Condition of all the remaining teeth
- Periodontal/Caries
Condition of the ridges
Inter-occlusal space
Supra-eruption of teeth
Occlusion
- Attrition/Wear Facets
- Interferences
Which Teeth are Valuable?
(5)
Canines?
Premolars/Lone standing premolars?
Maxillary incisors?
Mandibular incisors?
Molars?
Which Teeth Require Surveyed
Crowns?
(4)
Abutment teeth with large restorations
Abutment teeth with existing crowns that cannot be modified
Supra-erupted teeth
Teeth without the needed contours (guide plane, undercut, etc.)
Let’s Make a Surveyed Crown
Things to do prior to cutting the crown
(4)
Design the RPD (have it approved)
Identify any necessary changes in the occlusal plane
Make RPD preparations on the other teeth involved
Fabricate a COMPLETE ARCH custom tray
Preparing the Crown
(3)
Minimal changes from a conventional crown preparation
Additional reduction to allow space for rest seats or to allow for
guide planes on teeth that have drifted
Evaluate and identify the appropriate occlusal plane and adjust
occlusal reduction as needed. (Warn patient of possible pulpal
exposures and need for RCT or TE)
Evaluating and
Preparing the
Model Work
(2)
Survey the cast and
draw tripod marks
If there are no
posterior stops, an
additional
appointment will be
needed to record the
VDO/jaw relation with
a wax rim.
Fabricating an occlusal registration
when posterior occlusion is not
present:
The lab should provide a pindexed model and a static model
A wax rim should be fabricated on the — cast
A wax rim may also be necessary for the opposing arch if minimal
natural occlusion is present
Pt returns and provisional(s) removed
Wax rim placed and occlusion record made with Regisil
Provisonal(s) recemented and — model articulated using
the wax rim and occlusal registration
STATIC
PINDEXED
The Lab Script
The RPD modifications need to be
indicated in your lab script (guide
planes, rest seats, designated undercuts)
Example:
Please fabricate #3 PFM surveyed
crown using UMKC design #9
including a M guide plane and MO
rest in metal and a 0.01” DF
undercut. Shade A2.
Please fabricate #15 noble metal
surveyed crown with a M guide
plane, MO rest seat, and 0.01 DF
undercut
Cementation
(3)
Utilize the same techniques used with traditional crowns.
Evaluate inter-occlusal clearance with rest seats
Verify guide planes and undercuts with other abutment teeth
Fabricating a surveyed crown on a
posterior mandibular tooth to an
ideal occlusal plane when there is
no opposing occlusion is present or
an opposing denture is yet to be
fabricated
Use the same anatomical
landmarks you would use with a
mandibular denture.
WARNING!!!!
The use of the plane created with
the anterior teeth and the retromolar
pads only works if the
anterior teeth
have not supra-erupted.
If the anterior teeth have supra-
erupted, a maxillary wax rim or
maxillary denture wax try-in will need
to be competed first followed by
fabrication of anterior surveyed
crowns or enameloplasty to ensure
proper height.
Scenario #2
Fabricating a surveyed crown to
correct an issue with supra-
eruption.
Wax an opposing tooth to an ideal
occlusal height.
Reduce the
occlusion of the
supra-erupted
tooth on a
duplicate cast to
the ideal waxed
occlusion.
Make a vacuum form matrix on the
cast with the corrected occlusion.
Utilize the clear matrix to evaluate
for adequate reduction.
Take Home Tips
(3)
Evaluate the “Whole” not the “Hole”.
The prognosis of an RPD is only as good as it’s weakest abutment.
Do not compromise the minimal treatment necessary due to the
patient’s finances (or lack there of).
