Download point angles

# 23 Full Crown Wax Up
#23 Full Crown Wax Up
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Standardized Approach
Terminology & Nomenclature
Waxing Techniques
Dental Anatomy
Standardized Approach
• Follow a logical series of steps
• Use anatomical references that
are present:
• on the tooth peg
• adjacent teeth
• contra-lateral tooth
• opposing teeth
• A purely artistic approach is very
difficult
Anatomical References
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Embrasures
Line Angles
Heights of Contour
Point Angles
Proximal Contact
Areas
#23 Tooth Peg
The tooth peg is actually a prepared #23 dentoform
tooth.
The adaptation &
contour of wax at
the finish line
creates the
margin.
The end of the
preparation is the
finish line.
Notice the smooth
transition from the
un-prepared
portion of the
tooth peg to the
image of the
crown form. Your
wax ups should
demonstrate the
same smooth
transition from
unprepared tooth
peg to wax.
Focus on One component at a Time
• Evaluate each component from
multiple views:
• Facial
• Lingual
• Occlusal
• Lateral
Beginning at the most incisal point, add a thin coat
of wax to the prepared surface of the peg. Melt
each addition into previously applied wax.
Establish Fit and Contour at the Margin
Add a band of wax
around the margin;
melt wax into and
past the finish line.
Add slightly more
contour than you see
on the unprepared
tooth peg.
Creating a Margin
Use a Hollenback
carver to carve the
wax flush with the
finish line and with
the proper contour.
The margin will
become very distinct
when properly
carved. This is a
mechanical process.
Begin the margin
trim with the tip of
the carver in
contact with the
tooth peg below
the finish line.
The blade of the
carver is 90° to
the wax.
As you carve
away wax rotate
the blade toward
the finish line.
As you continue to
carve away wax
rotate the blade
toward the finish
line until the
unprepared tooth
structure stops you.
This is a learned
tactile skill. The
only thing you
observe visually is
the appearance of
a clean, distinct
junction.
Keep the wax shavings under control!
Locate Proximal Contacts
Occlusogingival Proximal Contact Location
Typically the occlusogingival location of proximal
contacts is most occlusal at the midline and moves
more gingival as you move away from the midline.
Faciolingual Location of Proximal Contacts
With a pencil, mark the “typical” location for the
mesial proximal contact. The red mark indicates
where the contact would need to be for a rotated,
overlapping tooth.
Mark the location for the distal contact of #23. You
can look at the contralateral contact area for
reference.
The arch is “turning the corner” at this
point. It is very easy to place your mark too
far to the facial.
Beginning with a small increment of wax build a
cone toward one of the marks. Verify that you
are heading in the correct direction.
Add small increments to the cone, allow the wax
to cool slightly (allow the shine to disappear),
then replace the peg in the dentoform. Continue
until the cone makes firm contact with the mark.
Repeat the process for the distal proximal contact.
Proximal contact location are very specific, try to be
precise with your cone locations.
From “Ten Rules for Developing Contours in
Restorations” Dr. James G. Burch, D.D.S.
Rule 5: “The proximal surface between the
marginal ridges and the CEJ is always flat to
slightly concave both buccolingually and
occlusocervically.”
Paraphrase: Proximal surfaces are relatively flat
from the contact area to the cervical line.
We can now add wax from the margin we created to
the proximal contact that we created, keeping the
surface relatively flat.
Distal
Mesial
Inspect from the facial:
Are the gingival embrasures open? Compare
these to the contralateral embrasures. The profile
of the proximal surfaces should be relatively flat.
Make the same comparisons from the lingual.
What do we do next?
What visual references do we have for the
proper positioning of the incisal edge?
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Occlusal embrasure form
Facial & Lingual embrasure form
Facio-incisal and linguoincisal line angles
Opposing tooth contacts
Contralateral outline form
Occlusal Embrasure Form: Form the point angles
(corners) of the incisal edge so that the occlusal
embrasures are mirror images of the contralateral
embrasures.
Add wax to the mesial and distal occlusal
embrasure areas. Use the contralateral tooth
as a guide.
Add wax between the mesial an distal point angles;
this gives you an initial indication of the outline
profile when viewed from the facial. To this point
you are referencing occlusal embrasure form.
Opposing tooth as reference: You can
manually position the lower member of
your dentoform so that the teeth adjacent
to #23 are in contact.
At this position the incisal edge of #23 should
either be slightly in contact or be slightly out of
contact with the opposing tooth.
Facial
embrasure
Occlusal View
Lingual embrasure
Facioincisal Line Angles
Linguoincisal Line Angles
The facioincisal & linguoincisal line
angles form the faciolingual boundaries
of the incisal edge. These are very
useful references to use in positioning
the incisal edge.
Add wax to develop the faciolingual width & location
of the incisal edge. Your references are the facial
embrasures, facioincisal and linguoincisal line
angles. This step is viewed from the incisal.
Facial & Lingual Line Angles
• Transitional junctions between one surface
and another, i.e. facial to mesioproximal
• Properly positioned line angles yield
proper contours & pleasing esthetics.
Distofacial Line Angle
Mesiofacial Line Angle
Add wax to create the mesiofacial and distofacial
line angles. Reference: the contralateral tooth.
Check and adjust these using facial, occlusal
and lateral views.
Lateral View
Occlusal View
- Evaluate facial embrasures
The lingual line angles of anterior teeth are the
marginal ridges. The lingual height of contour is
the cingulum. Add wax to create these structures
using the same methods that were used on the
facial.
Lingual View
Occlusal View
Evaluate lingual embrasures
Remove the tooth
from the
dentoform. There
will be “gaps”
between the
line angles just
formed and the
proximal surfaces
that were formed
previously. Blend
these areas on all
four line angles.
From either proximal view the waxing should
appear to be complete. Do not try to eliminate the
facet at the proximal contact.
Complete the facial surface, including the height of
contour. The boundaries are in place. The wax will be
thin over the facioincisal aspect of the peg. Evaluate
contours from facial, occlusal and lateral views.
Complete the lingual fossa. Remember that a
fossa is slightly concave.
Cleiod “Claw”
Discoid “Discus or Round”
The discoid end of the Cleiod-Discoid carver is
handy for refining the lingual fossa.
Final Contouring and Smoothing
• Heat smooth as well as you can
• Plane the surface with a carver
• Make necessary adjustments with
additions of wax and/or heat smoothing
• Plane the surface again
• Repeat the sequence as needed
• Buff lightly with nylon or cotton
Use light pressure and hold the blade at a 90° angle
to the wax. Let the blade gently ride the contours
that you have developed. Apply more pressure only
when you want to reduce a contour.
One of the final steps is re-sealing the margins.
First, re-melt the wax into the junction of the margin
and finish line. Then add a small excess of wax over
the junction & heat smooth to incorporate. Re-trim
the margin and blend the contours.
Facial View
Lingual View
Lateral View
Occlusal View
Remove the waxing from the dentoform and verify
that the transition from the unprepared tooth to the
wax is smooth. At this point you can hold the
unprepared #23 tooth adjacent to your wax-up and
compare contours.
Nomenclature :
Dilaceration-an abnormal angulation in the
Root (or crown) of a formed tooth.
Passive Eruption
Normal Recession of the periodontium resulting in a longer clinical crown. This is called
“passive” eruption since the teeth are not really moving or erupting, but the receding
gums create the impression of active tooth movement.
Passive eruption
Alerted Passive Eruption
• Root of the Maxillary central incisor has a small
distal inclination
AXIAL INCLINATION
Proximal view: 28 degrees(apex tilted lingually)
Labial view: 2 degrees(Apex tilted mesially)
I know that something is not right but I
can’t figure out what it is!
Midline/Facial View – Symmetry at the midline is the
most important esthetic consideration.
Midline/Facial View – Symmetry at the midline is the
most important esthetic consideration.
Midline/Facial View – Symmetry at the midline is the
most important esthetic consideration.
Midline/Facial View – Symmetry at the midline is the
most important esthetic consideration.
Locate Size and Location of Proximal Contacts
Great view for seeing contours of an
anterior tooth.
While focusing on the midline, make sure all four
point angles on the incisal edge are of the correct
length and shape.