try-in of Complete removable denture .pdf

Complete Denture
Try in
DR. Marwa Amer
Lecturer of Prosthodontic Department
Faculty of Dentistry
Tanta University

• Def
• Objectives
• Extraoral examination
• Intraoral examination
• Patient approval

The process of placing a trial denture in the patient’s
mouth for evaluation the fit, esthetics,
maxillomandibular relations. GPT

Once the denture has been processed it is
difficult to make any changes whereas in try
in stage changes can be easily made

1) Identification and correction of any errors
before the denture are finished
2) Allowing the dentist to check all previous
recordings
3) Permit the patient to assess the appearance of
the dentures

Try in of complete denture
Extra oral
Intra oral
Patient approval
Phonetic test

Articulator
Master casts
Trial denture
base
The teeth
Occlusion

1. The vertical dimension of occlusion is properly maintained
(The top of the incisal pin is flush with the upper member
of the articulator and the incisal pin is in contact with
incisal guide table).
2. The mounting rings are firmly screwed in their positions.
3. moves smoothly from centric to eccentric positions
without interlocking of cusps.
4. When the articulator is locked in centric, no other
movements are permitted other than simple hinge
movement
5. In centric position, the joints must be firm and not loose.
❑On the Articulator

❑ The Master Casts
• As the finished denture is processed on the master cast. So,
the master cast should be:
✓Has 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.
✓Undercuts should be relieved to avoid scratching the cast
by the trial denture bases

❑The Trial denture bases:
Checking 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
✓ The border should be shaped to conform to the depth
and width of the sulci

try-in of Complete removable denture .pdf

❑ The teeth:
➢ Proper selection
- all instructions recorded on pt’s chart are fulfilled regarding shape, size, shade, type,
material .
➢Proper setting up of teeth:
-Upper anterior teeth should overlap the lower anterior teeth 1–2 mm, horizontally
and vertically (without touch except in edge-to-edge relation)
-The lower incisors do not protrude beyond the labial vestibule , should present a
curve when viewed from the occlusal surface (depends on the shape of the
underlying alveolus).

- Posterior teeth are in maximum interdigitation (when checked from both buccal,
lingual aspects)
- Lower posterior teeth should lie vertically on the crest of the ridge for better
stability of lower denture
- The posterior end of the occlusal plane should be located at the junction between
the middle and the distal thirds of the retro molar pad

➢Check for free articulation, balanced occlusion:
- Teeth set up should show free articulation of teeth when articulator is
moved from centric to any eccentric position without interlocking of
cusps

After being satisfied with the case
on the articulator
Intraoral examination of the trial
dentures

To reduce the risk of cross- contamination, the trial denture
should in a suitable antiseptic solution, washing in running
water , before inserted in patient mouth.
Upper
denture
Both
dentures
together
Lower
denture

Trying in of upper denture:
1. Extension (labial , buccal ,Posterior )
2. Retention
3. Stability
4. Lip contour and occlusal plane orientation

The entire periphery should be checked to ensure that it’s not
over or under extended
- If Overextended…..TDB tend to move away when seating
pressure is removed)
1- by visual examination of labial , buccal flanges after slight
raising of lip (horizontal retraction)
2-by palpation: at the tuberosity with mouth slightly open
1- Denture base extension

▪ Posterior extension
• The posterior border of the upper trial denture base should be seen to
extend from one hamular notch to the other, a long the vibrating line
of the soft palate.
• If the posterior palatal seal was not done before. it should be done at
this stage before processing the dentures

If retention is not as good, the cause should be identified and
corrected.
Contributing factors include:
A. absence of border seal resulting from underextension of
the denture base,
B. inadequate width of the flange,
C. ineffective seal at the posterior border
D. poor fit of the denture base
2- Retention

How to test the retention of the 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}.
Apply a tipping force
to the anterior
incisors to break the
seal
Apply upward &outward
pressure on the canine to
test the seal at tuberosity
area at the opposite side

Retention
It is noted that the retention of the trial denture is less
than that of completed denture, due to
1-Absence of a posterior palatal seal
2-Poor adaptation of the trial denture base to the tissues
As min requirement, The trial denture should stay in
position when the mouth is opened.
in patients with unfavorable anatomical factors: Looseness
of the upper trial denture may make it impossible to carry
out an accurate assessment of the occlusion denture
fixative can be used

3- Stability
It is the quality of a denture to be firm, steady or constant to
resist displacement by functional horizontal stresses.
▪ It is tested by applying pressure in a tissue-ward direction
with the ball of the index finger in the premolar and molar
regions on each side alternately. No rocking shod be found
▪ This pressure must be directed at right angles to the occlusal
surface where displacement does occur.

Causes of Denture Instability
a. Warpage of the denture base
b. Posterior teeth set buccal to the underlying alveolar ridge
c. Hard unrelieved area in the midline e.g torus palatinus.
Careful diagnosis of the causative factor will help in
identification of the problem so that it could be corrected before
the dentures are finished.

4- Occlusal plane orientation
➢ Properly oriented occlusal plane is important to patient esthetics, patient
comfort, chewing function, and the balance of occlusion.
The orientation of the anterior end of the occlusal plane is determined by
esthetics.
➢The amount of upper anterior teeth that will be seen during speech and
facial expression depends on the length and movement of the upper lip. If
the upper lip is relatively long, the teeth may not be visible when the lip is
relaxed or during speech and the reverse is true
➢The occlusal plane should be parallel to the interpupillary
line anteriorly and to alatragal line posteriorly

5. Lip contour
The trial denture should provide sufficient lip and cheek support.
• The position and expression of the lips is the best guide for determining the
anterio-posterior orientation of the anterior teeth.
• If the anterior teeth positioned too far posteriorly then this will result in
insufficient lip support as well as dropping of the corners of the mouth.
•
• If the anterior teeth positioned too far anteriorly then the lips are contracted
giving a stretched tight appearance and this will dislodge the denture during
function.

• Extension of the denture bases (labial, buccal,
posterior and lingual extensions)
• Retention
• Stability
• Height of the occlusal plane
• Tongue space

1. Extension of the denture bases
(labial, buccal, posterior and lingual extensions):
▪ tested with the patient mouth is opened no more than half opened
position to allow the surrounding musculature to be in an acceptable
state of relaxation.
▪ Labial and buccal extensions are checked as for the upper denture,

Clinical steps in lingual border extension
examination:
▪ The disto-lingual area: ask the patient to protrude the tongue to moisten the
lips. If the denture base lifts at the back so, the lingual pouch is overextended.
• The lingual area: ask the patient to move the tongue to bring the tip of the
tongue into contact with the cheek on each side so, any displacement of the trial
denture which arises note the site which extent.
The under extension is determined by the intraoral examination as the depth of
the sulcus will be greater than that of the denture flange.
• The lingual frenum area: ask the patient to curl the tongue backwards to touch
the posterior palatal tissues by the tongue tip; if the trial denture lifts in the
front, it is overextended.

2. Retention
Usually, the lower denture retention is poor when compared to the
upper denture.
This is due to the small denture bearing area and difficulty in obtaining
an efficient border seal.

3. Stability
• Stability of the lower trial denture is checked as for upper denture.
• Observation of the relationship of the tongue to the occlusal surface
of the lower denture,(the lateral margins of the tongue should be seen
to be lying over the occlusal surface of the posterior teeth).

4- Height of lower occlusal plane
• The position of the lower teeth is assessed relative to the
lower lip and retromolar pad, the height of the occlusal
plane in relation to the tongue should also be noted .
• When the tongue is relaxed it should be able to rest on
the occlusal surfaces of the teeth which favors the
retention of the lower denture
• 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.

5. Tongue space
▪ The positioning of teeth in the neutral zone is of particular importance in the
case of the lower denture because the physical retention is relatively weak.
▪ Neutral zone: is the zone where the inward pressure of the lips and the checks
is neutralized by an equal and opposite outward pressure of the tongue;
▪ The area or position where the forces between lip , cheeks and tongue are
equal, teeth should be located in this space…..outside this zone will cause
dislodge of denture

Lack of tongue space (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 and whenever the tongue
moves the denture will move.
▪ The movement of the denture caused by lingual overextension will not
be apparent until the tongue has risen some distance.

• Evaluation of the vertical dimension of occlusion
• Evaluation of the centric occlusion position
• Equilibration of occlusal forces
• Balanced occlusion
• Appearance

A – Evaluation of the vertical
dimension of occlusion
• The patient should be seated in an upright position
• The patient head is not supported by the headrest (the headrest may
affect the physiologic rest position of the mandible so; it affects the
amount of interocclusal distance.

Combination of methods to evaluate the vertical
1-Facial measurements
2-Phonetics
3-Esthetics
4-Patient's proprioception

1- Facial measurement
• Instruct the patient to wet his lips, swallow, and then allow his
mandible to rest.
• While the patient is in resting position. See if his teeth are touching, or
there is adequate space between his teeth.
• If the teeth are in contact while the mandible is at rest, the vertical
dimension of occlusion is high and need a new record of vertical
dimension of occlusion.

2 – Phonetics
➢ It is difficult to locate speech problems at the try-in stage because the
tongue not react with the wax as they do with the finished denture
and lips do not react the same with the polished denture base.
➢ But to accept the correct vertical dimension, the patient should put
through a series of phonetic test

Phonetic tests
• (F, V, PH) Labio-dental sounds determining proper tooth position.
• Letter (S) determining relationship of upper & lower anterior teeth
NB. If maxillary anterior teeth are placed Too far labially:
- it cause patient whistling
- ( S ) become (ch)
Causes of Speech defect in complete denture:
• Poor fit
• Improper arrangement of teeth
• High vertical dimension
• Reduced tongue space

1- Evaluation of the "closest speaking space”
Ask the patient to say s,s,s or count from 50 to 60
▪If the teeth make contact during speech, indicate that there is not
enough interocclusal distance between the teeth ( VD)
▪If there is whistling during saying sss, VD or the upper teeth are
inclined palatally with no sufficient overjet.
▪thickness of palatal area of upper denture may affect .

2-Instruct the patient to say "th"
▪{The tongue should protrude to occupy the interocclusal space}
▪If the interocclusal space is less than 2 – 4 mm
▪ the anterior teeth may be placed too far anteriorly, or the vertical
overlap may be so great that there is insufficient space for the
tongue to protrude between the teeth.

3-Instruct the patient to pronounce "m" rapidly
• The mandible should remain stationary while the lips contact each
other to make sound.
4- Instruct the patient to pronounce "t" and
"d“
These sounds are formed by contact of the tip of the tongue with the
anterior palate and lingual surfaces of the upper anterior teeth.
▪ If the upper teeth are placed too far lingually the "t" will tend to sound
like a "d".
▪ If the teeth are set too far labially, the "d" will sound like "t".
▪ There is over opening or over closing which will need to be corrected
by determination of a new vertical dimension.

5-"Instruct the patient to say "f" or "v (labiodental
sounds)
▪ To evaluate both the anterior – posterior, superior – inferior position of
the maxillary teeth
▪ If the incisal edges of the upper anterior teeth contact the lingual side of
the lower lip, so the upper anterior teeth are set too far lingually or the
lower anterior teeth are set too far labially.
▪ Difficulty in making contact between the lower lip and upper teeth
usually indicates that the maxillary anterior teeth must be moved
downward.
▪ The upper teeth are placed too far inferiorly if the incisal edges depress
the lower lip when the "f" and "v" sounds are formed

3– Esthetics
1- Facial form is an important guided to whether the patient is at the correct vertical
2- If the appearance of the patient from the front face and the lateral view --
approximation of the nose and chin, lips will be seen to be pressed too firmly together
with loss of vermilion border when the mouth is closed is like an old man this
indicated low vertical dimension
3- If the patient appear with his facial muscles are stretched, this indicated that there
is high vertical dimension

4 – Patient's proprioception
Ask the patient if:
➢He has the feeling that the teeth touch before his jaws are closed far
enough….high VD
➢If he feels that he closed too far before the teeth touch, this indicate low VD
➢If he feels that the teeth touch at about the right moment this means that
.it has correct vertical dimension

Correction of the vertical dimension of occlusion
If the interocclusal distance is too large
• adding appropriate thickness of wax to the occlusal surfaces of the
posterior teeth of the lower denture,
• adjusting the wax to produce an even occlusion at the desired occlusal
face height (VD) and then recording the jaw relationship in CR

The interocclusal distance is too small or absent
- Posterior teeth will be removed and replaced with a new wax, removed from
one of the trial dentures occlusion rim before a new record is made.
- However, note should be taken of the relation between the upper and the
lower anterior teeth,
- if it reached a point which prevent more closure, so the anterior teeth should
be removed from the lower trial denture and replaced with wax occlusion rim
- {occlusal plane should be examined, if it is correct all alterations should be
done on the lower occlusal plane, if it is not correct so a new one is made}.
o The wax occlusion rim is trimmed to occlude with the opposing teeth at the
new vertical dimension

B – Evaluation of the centric occlusion
position
• If the maxillomandibular relation wax correctly recorded, the teeth
should inter-digitate in the mouth in exactly the same manner as they do
on the articulator, when both condyles occupy their most posterior
functionally unstrained position in the glenoid cavity.
• If the opposing cusps fail to inter digitate, when the denture is inserted
in the mouth, this will indicate that the previous centric jaw relationship
record was incorrect. In such a circumstance a new centric jaw
relationship record will have to be recorded

To check the centric occluding relation
• Ask the relaxed patient to touch the posterior edge of the upper denture
.base with the tip of his tongue and slowly close the teeth together.
• The lower trial denture can be stabilized in its place by placing the index
fingers of both hands on the trial denture flanges in the premolar region,
while the thumbs are held gently under the lower border of the mandible.
• The tip of the cusp should meet its
corresponding fossa. But if the initial
contact between teeth is cusp incline to
cusp incline, an anteroposterior shift of
the mandible or denture is affected.
This means that the centric relation of
the jaws is not in harmony with centric
occlusion of the teeth

Correction of centric occlusion / relation disharmony
A new recording of centric relation position should be obtained after
the teeth from one of the dentures have been removed and replaced
with a wax occlusion rim
• Before carrying out any modifications in the trial dentures the
dentist should determine first whether or not the occlusal
plane of the upper trial denture is correct
• If it is correct, the alterations will be carried out on the lower
trial denture.
• If the upper occlusal plane will have to be modified by plane is
not correct, the upper trial denture. replacing the teeth with a
wax occlusion rim

3-Equilibration of occlusal pressure
➢ As teeth occlude, they should move evenly with equally distributed
pressure all around
➢ It frequently occurs that teeth on one side of mouth occlude slightly
before the teeth on the other side, this is escape notice at try in
especially when TB have little, or no retention denture will sink on site
of heavy pressure rise on other side if little pressure this appeared to
be in good occlusion
➢Sometimes when posterior teeth occlude before anterior teeth , lower
dentures sink posterior rise anterior the same thing if anterior teeth
occlude before posterior teeth

This may be due to:
• Unequal pressure on the two sides of occlusal rim during registration
trial denture base
• Touching at rear preventing teeth from coming into occlusion
• Error in seating the base on their cast due to warpage of base or
presence of wax or debris on cast
• Errors in mounting lower cast on articulator

Testing evenness of the occlusal pressure
1. Place two pieces of thin celluloid strips between the posterior teeth on each
side, ask the patient to close firmly and then try to pull the strips, any
difference in the force required to remove the strips is interpreted in terms
of difference in occlusal pressure. repeat at premolar region
2. Stabilize the upper and lower dentures with the thumb and index fingers of
both hands. Request the patient to close gently and slowly, and to stop
closing at the first tooth contact. Try to see the first contact and feel the
dentures rise from their basal seats.
3. Gross error in recording the occlusal position may be tested by inserting
the blade of the wax knife between the occluding surfaces of the upper and
lower posterior teeth on both sides.

Correction of unevenness of occlusal pressure:
If the error is slight:
• Gently soften the wax supporting the teeth of one denture on the offending
side (heavy pressure side).
• Insert the trial dentures in the patient mouth and hold the lower denture
firmly in place.
• Ask the patient to close. The teeth on the side of heavy-pressure will sink
slightly into the softened wax until the
• occlusion on the opposite side arrests them, thus equalizes the occlusal
pressure.
• The trial dentures sent directly to the processing procedure without putting
on the articulator. This method has the disadvantage that it will be difficult
to carry out laboratory remounting and selective grinding

If the error is gross
• A layer of softened wax is added between the occlusal surfaces of the
teeth on the side of light or no occlusal contact and the patient is asked
to close until the teeth on the opposite side will stop them, equalizing the
occlusal pressure. This is followed by remounting of the lower cast and
correcting the occlusion on the articulator. Or
• The posterior teeth are removed from one denture and are replaced by a
wax occlusion rim which should be trimmed to occlude with the opposing
posterior teeth without altering the original vertical dimension of
occlusion as set on the articulator. Then a new record of the retruded
contact position is taken and the lower cast is remounted on the
articulator for correction of the occlusal discrepancy

4- Balanced occlusion
➢Simultaneous contact to stabilize denture bases on their respective
ridges result from coordination of condyle path inclination, incisal
guidance, cusp height, compensatory curves, occlusal plane
➢occlusion is balanced when there is contact of at least three widely
separated points in any lateral or protrusive positions

• One of the main objectives in complete denture prosthodontics is to
produce a harmonious appearance of the denture when view the patient
from the front face and lateral view when the mouth is closed and also
in a half open position.
• evaluate the teeth while the patient rests, speaks, and smiles. This
assessment is important because dentures which have pleasant
appearance may suddenly become unsuitable if the patient moves his
lips during function.
5-Appearance of face and teeth

1- The midline:
• The midline of the upper and lower trial
dentures is evaluated in relation to the midline
of the patient's face. If it is incorrect, the upper
and lower teeth will have to reset to correct it.
2- Smile line:
• The incisal edges of the maxillary anterior, and
premolars should form a smile line which is
consistent with the age, sex, and personality of
the patient. This curvature tends to decrease
with age, and also tends to be flatter in men
than in woman. When the patient's smiles, the
maxillary teeth should just touch the lower lip
and should follow its curvature. The reverse
smile line or curvature should always avoid.
To achieve the best esthetic results certain aspects of appearance,
have to be checked as a routine:

3- Corners of the maxillary arch:
• The maxillary canines should be located at the corners of the mouth.
• A buccal corridor should be evident between the teeth and the
cheek.
• The patient must not exhibit an ear-to-ear smile.

4- Verify tooth selection:
• The appearance of the denture includes the shade, mould, and
size of the teeth, the orientation and level of the occlusal plane and
hence, the amount of the tooth visible and the degree of lip
support.
• If the shade and arrangement appear unnaturally uniform, mixing
shades and moulds may be indicated.
• In some patients the upper labial flange will be visible during
speech and smiling. In this case, a natural appearance will be
achieved when the acrylic flange is contoured to resemble natural
gum and the acrylic flange is slightly irregular or stippled to break
up any reflections.

5- Regularity of anterior teeth:
• The anterior teeth should not be placed so that the incisal edges are all at
the same level.
• Some form of crowding should be usually present in the arrangement of
the anterior teeth. This may be varying from minimum irregularity to
marked overlapping of the teeth.
• Create the final appearance by detailed arrangement of the anterior teeth,
shaping the gingival margins and, where necessary grinding the incisal
edges.

Approval of appearance by patients
• The patient should view the dentures at a normal speaking distance
within the context of the total appearance of the face. This should be
in front of a wall mirror,
• it's advisable to ask the patient to bring relative or a friend with him
at time of try in, for his or her opinion

try-in of Complete removable denture .pdf

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