Transcript DENTURE PLACEMENT & PATIENT EDUCATION

Denture Placement & Occlusion
Correction
Rola M. Shadid, BDS, MSc
Causes of Denture Errors
 Clinical errors
 Technical errors
 Inherent deficiencies in the material
itself
Evaluation Procedures
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Processing
Polished surfaces
Tissue fit and comfort
Retention, stability and support
Jaw relations
Occlusion
Esthetics
Speech
Evaluation of Processing *
 Inspect for processing errors, e.g.
porosity
 Inspect for inadequate polishing
 Run your finger along the borders &
impression surface to check if sharp
edges or acrylic spicules exist
 Examine frenal notches for sharp
edges
 Examine for adhered plaster or stone
fragments
Patient Education & Preparation *
• First oral feeling with fullness is normal
& will disappear over time
• Excessive salivation
(compulsive spitting or rinsing should be
avoided, instead swallowing encouraged
to remove excess saliva)
Evaluation of Tissue Fit &
Comfort
Pressure Indicating Paste (PIP)*
• Every new denture must be checked
with PIP to identify and determine if
pressure areas exist to reduce them.
Evaluation of Tissue Fit &
Comfort
• Never adjust unless you can
see exactly where to adjust
• Use indicator medium
- (PIP, indelible marker, etc)
Place Paste with Streaks
How to Read PIP?
• Streaks - no
contact (N)
• No Paste Impingement (I)
• Paste, no streaks
- normal contact
(C)
Evaluation of Tissue Fit &
Comfort
Severe undercuts
• Cause abrasion and soreness in
seating and removal
• Management
Relieve with extreme caution with
aid of PIP
Evaluation of Tissue Fit &
Comfort
Overextended borders
• Denture appears to rise or has
inadequate retention
• Management
Identify the offending borders, mark with
indelible marker inside the pt mouth and
carefully reduce
Evaluation of Retention,
Stability & Support
• Test for retention*
• Test for posterior palatal seal
Test for Rocking
• Apply alternating finger pressure
on occlusal surfaces of R & L
sides
• Rocking around fulcrum point
• Midpalatal raphe is a common
fulcrum point if inadequate relief
has been provided *
Evaluation of Occlusion
• Denture processing almost always causes
changes in occlusion due to dimensional
changes in resin
• These changes are usually manifested as
increase in OVD
Causes of Occlusal Errors
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Errors in impressions
Ill-fitting trial denture bases
Inaccurate jaw relation records
Errors during transfer of the records
to articulator
• Incorrect arrangement of posterior
teeth
• Dimensional changes during curing
• Processing faults……..*
Why is it difficult to detect
occlusal errors in the
mouth? *
Negative attitude (assume an
error exists and try to find it)
What is the ideal occlusal contact?
At first contact, even maximum
intercuspation at CR without denture
shifting or instability & without pain *
Types of Occlusal Errors
• CO not coincide with CR
• Premature contact (high point) in one or
both sides
• Uneven distribution of occlusal contacts
• Eccentric movement prematurities
(protrusive & lateral)
What are the Methods of
Detecting Occlusal Errors?
 Touch & slide method (Refer to lecture 9)
 Denture dislodges or shifts when pt
occludes
 Pt complains of pain beneath
denture bases
Correction of Occlusal
Errors
1. Laboratory remounting
2. Clinical remounting
3. Direct intraoral correction
Laboratory Remounting *
Disadvantages
Cannot correct errors made while
recording jaw relations
Cannot correct errors made while
mounting the casts on the articulator
Does not compensate changes caused by
settling of the denture bases
Clinical Remounting with New
Interocclusal Records *
Advantages
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Correct errors made during recording of
jaw relations, or while mounting cast on
articulator
Less chair side time
Corrections away from the patient’s view
No saliva which makes detection by
articulating paper difficult
No shifting of dentures or incorrect closure
by pt
The Aim of Clinical Remounting
The prematurities are ground
until multiple, uniformly
distributed and even contacts
are obtained bilaterally
Clinical remounting is currently
the most commonly preferred
method of occlusal correction
Clinical Remounting
Procedure
• Ask patient to bite on
cotton rolls for 10 min.
• Guide mandible into
CR several times.
• Bite registration
material is placed on
the post. teeth of the
mandibular denture
Clinical Remounting
Procedure
• Guide mandible into
CR
• Obtain interocclusal
record of CR.
Clinical Remounting
Procedure
• Mount upper denture
using remounting jig
• Mount lower denture
Clinical Remounting
Procedure
Selective Spot Grinding *
The art of reducing premature
contacting surfaces, so that
an equal pressure exists at all
points with interference at no
point.
How to Recognize
Premature Contacts?
• A dark ring with a light
center usually denotes a
premature contact
• You should distinguish
betw. marks made by
normal occlusal contacts
and those of premature
contacts
• Articulating paper
should not be reused
many times and should
be changed often.
Selective Spot Grinding
Make grinding until
even (same intensity),
stable, and multiple
marks spread over wide
area in both sides
Eliminating Occlusal Errors
• Re-establishment of CO.
• Correction of protrusive relation.
• Correction of working side occlusal errors.
• Correction of balancing side errors.
Initially, centric occlusion errors are
corrected, followed by protrusive, R & L
lateral interferences.
Basic Tooth Positions
Balancing Contacts
Centric Occlusion
Working Contacts
Selective Grinding Rules to
Obtain CO
 After the first few taps on the articulating paper only a
few high contacts appear.
 The marking process and the grinding are repeated until
all except the anterior teeth contact in CO.
 Ideally all holding cusps * of the maxillary and
mandibular posterior teeth will make simultaneous
contacts.
 It is not uncommon for one or two functional cusps not to
make contact after establishing the final CO.
 It is not necessary to continue adjusting until these cusps
make contacts because aggressive adjustment will
sacrifice the established OVD
Selective Grinding Rules to
Obtain CO
 As far as possible, avoid grinding cusp tips
especially centric holding cusps, instead grind the
opposing fossae or marginal ridges where the
centric holding cusps occlude
 If the high contact is on the centric holding cusp
inclines, the cuspal inclines can be reduced, thereby
gradually moving the contact more toward the
bearing cusp tip.
 A centric holding cusp may be reduced when it
interferes with another centric holding cusp or when
makes interferences in centric and eccentric
positions
Re-establishment of CO
Problem: Teeth too long
Solution: Deepen the fossae
Re-establishment of CO
Problem: Teeth too nearly end to
end
Solution: Grind Inclines
Re-establishment of CO
Problem: Too much horizontal
overlap
Solution: Broaden central fossae
After the CO re-establishment….
• DO NOT:
- Reduce maxillary lingual cusps.
- Reduce mandibular buccal cusps.
- Deepen the fossae.
Correction of Protrusive
Relation
• The teeth are brought
edge to edge
• Any interferences to
smooth anterior gliding
of dentures are
eliminated by grinding
• Elimination of
protrusive interferences
along a path of 3 to 5
mm is sufficient
Correction of Working Side
Occlusal Errors
BULL rule
buccal upper-lingual lower
Correction of Working Side Occlusal
Errors
• Reduce lingual inclines of buccal cusps of
upper teeth.
• Reduce buccal inclines of lingual cusps of
lower teeth.
ON WORKING SIDE ONLY!!!
Correction of Working Side
Occlusal Errors
Problem: Buccal and
lingual cusps too long.
Solution: Change
inclines of balancing
cusps.
Correction of Working Side
Occlusal Errors
Problem: Buccal cusps are
too long
Solution: Change lingual
incline of maxillary buccal
cusp
Correction of Working Side Occlusal
Errors
Problem: Lingual cusp
too long.
Solution: Change buccal
incline of lingual cusp of
mandibular tooth.
Correction of Balancing Side
Errors
On the balancing side, the cusps usually
involved are the functional cusps and
therefore grinding becomes more
confusing
Correction of Balancing Side
Errors
• Decide which supporting cusp maintains
CO and reduce its opponent.
Correction of Balancing Side
Errors
Grind the lingual
incline of the
mandibular
buccal cusp.
Direct Intraoral Correction
Disadvantages
 Requires a lot of pt cooperation
 Pt should have good neuromuscular
control
 Saliva
 Inaccurate closure by pt
 Misleading due to resiliency of tissues and
shifting of denture bases
References
1. Boucher's Prosthodontics Treatment for
Edentulous Patients. Twelfth
Edition.Chapter 20.
2. Dalhousie continual education
3. Complete Denture Prosthodontics, 1st Edition,
2006 by John Joy Manappallil, Chapter 19