2. Definition
Try-in Verification / Aesthetic try-in :
“A preliminary insertion of a removable denture wax- up
or a partial denture casting or a finished restoration to
determine the fit, aesthetics, maxillomandibular relation.”
– GPT
Trial denture :
“A preliminary arrangement of denture teeth that has
been prepared for placement into the patients mouth to
evaluate aesthetics & maxillomandibular relationships”
- GPT
Importance:
It is the last opportunity to evaluate many of the
previous steps already accomplished.
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3. Objectives
1) To check and verify the established maxillomandibular
relationship:
Verify that centric occlusion and centric relation
coincide.
Test for the acceptance of the established vertical
dimension of occlusion.
2) To determine if the positions of the teeth and the
contours of the denture bases are compatible with the
surrounding oral environment.
1) To verify tooth selection and arrangement for proper
esthetics and phonetics.
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4. Various aspects of try in:
Extraoral examination of the trial dentures.
Intraoral examination of the trial dentures.
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6. The master cast
As the finished denture is processed on the master cast.
So the master cast should be:
In good shape.
Free from air bubbles or scratches.
Free from wax debris which lead to improper adaptation
of the trial denture bases leading to false relationships.
If there are any undercuts present in the cast, these
undercuts should be relieved to avoid scratching of the
cast by the trial denture bases.
7. The trial denture bases
Check the following:
The trial denture bases must be
stable.
The borders of the trial denture
base should be smooth, round, and
have no sharp edges.
Also the border should be shaped
to conform to the depth and width
of the sulci.
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8. On the articulators
The mounted cast is checked for:
a) Maintaining of the vertical
dimension of occlusion
Top of the incisal pin is flush
with the upper member of the
articulator.
The incisal pin is in contact
with the incisal table.
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9. b) The mounting rings are firmly screwed in their position
c) Moving of the articulator smoothly from centric to
eccentric positions without cuspal interlocking.
d) The trial denture bases lie properly on their casts and
the teeth meet evenly in centric relation.
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10. The teeth
It is the dentist responsibility to select the proper
shade, and mould of the teeth and to determine that
the teeth are set correctly.
Elimination of the excess wax is done to avoid the
camouflages of the teeth relationships to overlook the
occlusion.
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12. To reduce the risk of cross- contamination, the
trial denture should be sprayed with suitable
antiseptic solution and washed in running water,
before inserted in patient mouth.
1) Checking the trial dentures separately:
Trying- in the upper denture.
Trying- in the lower denture.
2) Checking the upper and lower dentures
together.
13. Maxillary trial denture
Denture base extension:
The labial and buccal extension:
marked overextension of the flanges, will stretch the
sulcus tissues and when denture is inserted, leads to
elastic recoil resulting in dislodgment of the denture,
immediate denture displacement after its seating.
Examination of the extension:
Insertion of the upper trial denture in its place with
light pressure on the occlusal surface, move the cheek
in functional movement. With the release of the
pressure, the denture will fall down.
Need adjustment till little or no movement occurs.
14. Also under extension of the upper trial denture leads to
poor physical retention.
Correction will usually entail making a new final
impression.
Provision of the frena {labial and buccal} should be done
to ensure that they have adequate clearance.
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15. Posterior extension
The posterior border of the upper trial denture base
should extended from the one hamular notch to the
other along the vibrating line of the soft palate, and
correctly placed on the master cast.
If the p.p.s is not done before, it should be done at
this stage.
Arbitary scraping of the cast and redapting the
record base
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16. Establishment of Posterior
Palatal seal
Advantages to placing the seal in Trial dentures :
1)Trial base will be more retentive, this can produce more
accurate maxillomandibular records
2) Patients will be able to experience retentive qualities of
the trial base, giving them psychologic security about
retention
3)Denture wearer will be able to realize the posterior
extent of denture.
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17. Retention
It is noted that the retention of the trial denture is
less than that of completed denture, due to:
Absence of a posterior palatal seal.
Poor adaptation of the trial denture base to the
tissues.
The trial denture should stay in position when the
mouth is opened.
Looseness of the upper trial denture makes it
impossible to carry out an accurate assessment of the
occlusion {may use denture fixative} especially, in
patients with unfavorable anatomical factors.
18. How to test the retention of
upper denture?
Seat the upper trial denture with a firm
upward and backward pressure.
Allow the tissues to settle around the
denture
Grip the labial and lingual surfaces of the
upper denture teeth between the thumb
and forefinger
Apply a firm downward vertical pull to
dislodge the denture away from the
tissues
If the retention is good, dislodgment of
the trial denture may be difficult
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19. Stability
It is tested by applying pressure in a tissueward direction
with the ball of the index finger in the premolar and molar
regions on each side alternately.
This pressure must be directed at right angles to the
occlusal surface where displacement does occur.
Causes of instability
Warpage of the denture base.
Posterior teeth set buccal to the underlying alveolar
ridge
Hard unrelieved area in the midline
e.g. torus palatinus.
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20. Orientation of the occlusal
plane
Properly oriented occlusal plane is
important to:
Patient esthetics.
Patient comfort
Chewing function
Balance of occlusion
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21. Orientation of the anterior end of the occlusal plane is
determined by esthetics.
The amount of the upper anterior teeth that will be seen
during speech and facial expression depends on length
and movement of the upper lip.
If the upper lip is relatively long, the natural teeth may
not be visible when the lip is relaxed or even during
speech.
The movement of the lips during function varies
considerably among patient thus , the amount of the
upper teeth that will be visible varies for each patient.
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22. Lower denture trial
Denture base extension:
The lower trial denture extension should be tested
with the patient mouth is opened no more than half
opened position to allow the surrounding
musculature is in an acceptable state of relaxation.
Labial and buccal extensions are checked as for
the upper trial denture.
23. How to evaluate lower denture retention?
Usually the lower denture retention is poor when
compared to the upper denture due to:
1. Small denture bearing area
2. The difficulty in obtaining an efficient border seal.
Testing of the lower trial denture retention:
a) Ask the patient to open his mouth slightly and let his
tongue touch the cingula of the lower anterior teeth,
support the chin of the patient with the left hand and
pull the teeth straight upwards to check the retention of
the anterior labial and lingual flanges.
b) Tilt the lower trial denture outward from the canine
region to test the retention of the opposite retro molar
pad.
24. Lower occlusal plane
In most patients, the incisal edges
of the natural lower canines and
the cusp tips of the lower first
premolars are located at the level
of the lower lip at the corner of
the mouth when the mouth is
slightly open.
The posterior end of the occlusal
plane should be at the level of the
anterior two thirds of the retro
molar pad.
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25. Tongue space
Natural teeth occupy a position in the mouth where the
inward pressure of the lips and the cheeks is neutralized
by an equal and opposite outward pressure of the tongue,
and it is in this zone of neutral pressure that the artificial
teeth must be set (neutral zone).
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26. To check for the neutral zone in the patient’s mouth, let the
patient open his mouth half-way and touch the lower
anterior teeth with the tip of his tongue, while his tongue is
relaxed. Feel the amount of pressure exerted by the tongue
and cheek on the lower teeth, using a plastic filling
instrument. Pressure should be roughly equal on the lingual
and buccal sides of the teeth.
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27. Lack of tongue space
(cramped tongue)
If the tongue is more mobile than the cheeks will cause
greater instability of the lower denture.
Cramped tongue may be due to:
1. Posterior teeth set lingually to the neutral zone.
2. Posterior teeth tilted lingually
3. Posterior teeth too broad bucco-lingual.
Testing of the tongue space:
Ask the patient to raise the tongue. If the tongue is
cramped, the denture will begin to rise immediately. As
the tongue moves it tries to expand laterally and
whenever the tongue moves the denture will move.
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28. Checking the upper and lower
dentures together
It is usually advisable to insert the lower
trial denture first and then the upper
because there is less chance of having the
upper denture drop down.
The patient should be seated in an upright
position.
The patient head is not supported by the
headrest (the headrest may effect the
physiologic rest position of the mandible
so, it effect the amount of interocclusal
distance).
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30. Verifying the Vertical dimension
Checking of labial frenum
Evaluation of Vertical dimension at rest & at occlusion
pre extraction records
amount of inter occlusal distance to which pt. was
accustomed
phonetics & esthetics
facial dimension & facial expressions
lip length in relation to teeth
inter arch distance & parallelism of the ridges
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31. Verifying Centric Relation
Intra Oral Observation of Intercuspation
Pt. is guided into CR by a thumb placed on the anteroinferior
portion of the chin & index finger bilaterally on the buccal
flanges of the lower denture.
Any Error in CR will be apparent when teeth slide over each
other.
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32. If Error is due to mounting :
anterior teeth if not placed to support lip, are corrected.
vertical overlap of anterior teeth are carefully noted .
posterior teeth are removed from lower occlusal rim
Impression plaster is mixed & placed on the rim.
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33. Pt. is instructed to close the mouth slowly until the
anterior teeth have same vertical overlap as they had
before the posterior teeth were removed.
After the plaster is set, rims are removed & this
corrected new record is mounted on a articulator.
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34. Extra oral articulator method
Process :
- Impression material (eg. Aluwax) is placed over mandibular
posterior teeth
- wax sealed – denture placed in mouth – just wax portion is
immersed in water bath of 130o
F for 30 secs – denture
placed back in pts mouth - mandible guided into CR so that
upper teeth makes contact with the wax – denture
removed & chilled in ice water & returned back to patients
mouth for re-checking
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35. – CR is confirmed – Trial dentures are then locked in
articulator – opposing teeth should fit in the indentation in
every way (anteriorly, posteriorly, laterally & vertically ) if
the original CR was correct.
- If it does not fit, mandibular cast should be separated &
remounted with last occlusal record.
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36. Eccentric relation records
It is essential that the movements of articulator should
simulate movements of the patient within the range of
normal functional contacts of teeth.
For this, condylar elements of articulator must be adjusted
so that they approximate condylar guiding factors within
TMJ.
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39. Creating facial & functional harmony
with Anterior teeth
Appearance of entire lower half of face depends on
dentures.
After vertical dimension of occlusion & CR has been
verified. To obtain a harmonious effect with the patient
face, modifications are made in arrangement of teeth
Incorrect positioning of anterior teeth or supporting base
material alters normal appearance of vermilion border, the
philtrum & mentolabial sulcus
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41. 1. Preliminary selection of
artificial teeth
Evaluated for size, form & color
6 anterior teeth should be of sufficient overall width to
extend approx. corner of mouth
Color should blend with the face
Any records used in initial selection
should be consulted & changes should
be made if it improves the appearance of patient
42. 2. Horizontal orientation of anterior teeth
Teeth set directly over ridges causes insufficient lip
support characterized by:
Drooping of corners of mouth,
Reduction in visible part of vermilion border,
Deepening of nasolabial sulcus,
Wrinkles over vermilion border
Excessive lip support causes stretched lips, tendency
of lips to dislodge dentures during function,
elimination of normal contours of lips, philtrum &
sulci.
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43. Labial surface of many natural central incisors are about
8 – 10mm from center of incisive papilla
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44. 3. Vertical orientation of anterior teeth
Index finger is placed on incisive
papilla with relaxed upper lip &
amount of finger covered gives
indication of length of upper lip.
Lower lip is better guide for
vertical orientation of anterior
teeth. Incisal edges of lower
canine & cusp tip of lower first
premolar are even with corner of
mouth when mouth is slightly open.
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45. If lower teeth are above then,
1. plane of occlusion may be too high
2. vertical overlap of anterior teeth may be too much
high
3. vertical space between the jaws may be excessive
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46. 4. Inclination of anterior teeth
Inclination of labial surface of residual ridges seen on
edentulous cast gives guide to inclination of anterior
teeth
Inclination of anterior teeth parallels the profile line
of face
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47. 5. Harmony in general composition of
anterior teeth
A. Harmony of dental arch form & form
of residual ridge:
I. Square arch form
Central incisors are more nearly in line with
canine
4 incisors should have little rotation to give
broader effect to teeth
II. Tapering arch form
Central incisors are greater distance
forward from canine
rotating or lapping of teeth may be present
III. Ovoid arch form :
teeth seldom rotated
show greater amount of labial surface
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48. B. Harmony of long axis of central incisors
& face
Imaginary perpendicular line from mid point of Inter
pupillary line should mark middle of dental arch to be in
harmony with face
Mid line also determined by observing position of incisive
fossa
Mid line of mandibular central incisor is aligned with that
of maxillary incisors
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49. C. Harmony of the teeth with smiling line of the
lower lip
Line formed by upper anterior teeth should follow curved
line of lower lip during smiling
Vertical positioning of upper canines are responsible for
shape of smile line
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50. Canines should be arranged in such a way that their
incisal edges should be slightly shorter than that of
lateral incisors, if not it will create reverse smile
line.
Reverse smile line is one of the frequent cause of
artificial appearing dentures.
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51. D. Harmony of opposing lines of Labial & Buccal
surfaces
Asymmetrical symmetry is essential for natural
appearing teeth
eg. If maxillary right lateral incisor is set at 5 degrees
to perpendicular then opposing lateral should be of
same angle but in opposite direction
Labial & buccal lines should be in harmony with lines of
face.
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52. E. Harmony of incisal wear & age
Incisal edges of denture teeth should be grinded to
simulate the wear surface that would have developed by
the time patient reached his current age.
This wear is placed on teeth where it would have occurred
during function & also where it assists in the mechanics of
balancing the occlusion
53. F. Harmony of spaces & individual tooth
position
Use of spaces between teeth can be effective in
emphasizing individual tooth position & natural
appearing arrangement
Spaces designed should be self cleansing
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54. Conclusion
For the success of a complete denture the teeth should
be arranged in harmony with the intraoral and circumoral
structures and adjusted so that they occlude and
articulate evenly.
After the preliminary arrangement of the artificial
teeth on the occlusion rims, it is essential that the
accuracy of the jaw relation records made with the
occlusion rims be tested, perfected if incorrect, and
then verified to be correct.
During Try-in all the procedures carried out in
fabrication of denture are verified clinically.
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55. References
Prosthodontic Treatment for Edentulous patients, 12th edition :
Zarb – Bolender
Essentials of complete denture prosthodontics, 2nd edition :
Sheldon Winkler
Text book of prosthodontics, Deepak Nallaswamy
http://www.slideshare.net/narendrabasutkar/try-in-complete-
dentures
www.gr.dentistbd.com
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