Single Denture
Dr: Hussein Abd El-hady Hussein Taha
Lecturer of Removable Prosthodontics and Implantology
Faculty of Dentistry – Minia University
Definition:
A single complete denture is a complete denture that occludes against some
or all of the natural teeth, a fixed restoration, or a previously constructed
removable partial denture or a complete denture.
*Construction and delivery of single complete dentures is more
complicated than the delivery of upper and lower complete
dentures on a patient.
Problems of single denture:
1.The ability of the patient to generate heavy occlusal forces, due to the
existence of opposing natural teeth.
Problems of single denture:
2. Single denture syndrome. This situation is the result of the displacement
of the maxillary denture due to unfavorable occlusal relationship as a
result of tipped, malposed or supererupted natural teeth. It is presented as
mucosal irritation and ridge resorption of the edentulous ridge.
Problems of single denture:
3. The occlusal form of the remaining natural teeth and the uneven occlusal
plan (“mutilated” dentition).
Problems of single denture:
4. Esthetic and phonetic problems due to the fixed positions of the
mandibular teeth.
How to Overcome These Problems
- The primary consideration for a continued success of a
single complete denture is the preservation of that
which remains.
- All fundamental steps in denture construction must be
followed and completed to perfection( without minor
errors).
How to Overcome These Problems
- The occlusal plane of the natural teeth in the opposing
arch must be made harmonious.
- Maximum base extension within functional anatomical
limits (distributed forces over the largest possible area of
supporting structures and the force per unit area kept at
minimum.)
How to Overcome These Problems
Reduction of the forces to which the denture is subjected:
1- Reducing bucco-lingual width of posterior teeth.
2- Maximum tissue coverage.
3- Balanced harmonious occlusion.
4- Use of resilient denture liner in the mandibular denture.
5- Use of implant supported fixed or overdenture prosthesis.
6- Skeletal class III ( Mandible larger than maxilla).
7- Extraction of remaining teeth and complete denture are constructed.
Diagnosis and treatment planning:
1- Complete case history is taken and oral examination is done.
2- Study upper and lower casts are obtained.
3- The upper cast is mounted on the articulator using a face bow.
4- The lower cast is mounted on the articulator using a provisional centric
inter-occlusal record at an acceptable vertical dimension.
5- Eccentric records are made and the condylar elements of the articulator
are adjusted.
Common Occlusal disharmonies:
The remaining molars are often severely inclined Mesially and then
Distal halves super-erupted.
If this situation is left unaltered there would be no occlusion in protrusive
and lateral excursions except for contact on the distal half of the lower
molar.
This results in the maxillary denture being easily dislodged during
functional movements.
Common Occlusal disharmonies:
Treatment:
a) If the molars are not severely tilted they may be reshaped by selective
grinding.
Common Occlusal disharmonies:
Treatment:
b) When tooth reduction is found necessary, the ideal treatment is to
restore the tilted molars with cast gold crowns, onlays, or a fixed bridge if
a large edentulous space exists mesial to the molars.
Common Occlusal disharmonies:
Treatment:
c) If a large space does exist mesial to the tilted molars, another
alternative treatment is to design a removable partial denture that would
restore the mesial half of the molars by using an onlay mesial rest
Common Occlusal disharmonies:
Treatment:
d) If the molars are severely tilted forward and super-erupted, and
modification is not possible, extraction is necessary.
Methods used for detecting occlusal modifications:
Several techniques could be used to determine occlusal modifications
that are necessary prior to denture construction:
I- Swenson’s Technique
II- Bruce Technique
III- Yurkstas’Technique
IV- Boucher’s Technique
Methods used for detecting occlusal modifications:
1- Swenson’s Technique
Upper and lower casts are mounted on the articulator. The upper denture is
constructed. If the lower natural teeth interfere with the placement of the
denture teeth, they are adjusted on the cast and the area is marked with a pencil.
The natural teeth are them modified using the marked diagnostic cast as a guide.
This technique is simple but time consuming.
Methods used for detecting occlusal modifications:
The occlusal plane discrepancy is readily apparent when the denture teeth are
properly arranged.
This discrepancy can only be corrected by restorative means.
Methods used for detecting occlusal modifications:
2- Bruce Technique :
Use of a clear acrylic resin template fabricated over the modified stone
cast. The inner surface of the template is coated with pressure
indicating paste and placed over the patient's natural teeth.
The Modifications are made on the Stone cast. A Clear Acrylic Resin
Template as fabricated over the modified stone cast.
Methods used for detecting occlusal modifications:
3- Yurkstas Technique
Use of a commercially available U shaped metal occlusal template that
is slightly convex on the lower surface. This template is often an aid
in detecting minor deviations in the occlusal scheme
Methods used for detecting occlusal modifications:
4- Boucher Technique
The interferences are removed by movement of the maxillary porcelain teeth over
the mandibular stone teeth.
Pre-maturities are identified and removed by grinding the natural teeth. The
procedure is repeated for right and lateral excursions until a harmonious
balanced occlusion is established.
METHODS USED FOR A HARMONIES BALANCED OCCLUSION:
Many techniques have been used to achieve a harmonious balanced occlusion of a
complete maxillary denture opposing natural teeth. They basically fall into two
categories:
1. Dynamic equilibration of occlusion by the use of a functionally generating
path.
2. Static equilibration of occlusion with an adjustable articulator.
MATERIALS FOR ARTIFICIAL POSTERIOR TEETH:
Acrylic
resin.
Porcelain.Gold Cast metal
Acrylic resin with amalgam stops.
ESTHETICS OF MAXILLARY SINGLE DENTURE
The fixed positions of mandibular teeth limit the esthetic position of
maxillary anterior teeth. How to solve the esthetic problem?
To create enough horizontal overlap to allow freedom to balance in
eccentric movements.
Or to steeping the posterior cusp angles so that the posterior teeth
will disocclude the anterior teeth during eccentric movement.
MANDIBULAR SINGLE DENTURE:
The prognosis of a mandibular single denture against natural teeth is
less favorable than when the full upper denture is opposed by natural
lower teeth . It would be difficult to classify this case as clinically
successful.
This is due to:
1- Excessive resorption of lower ridge due to greater stresses per unit
area delivered to the mandibular ridge by the natural teeth.
2- Occlusal problems: The presence of natural teeth will present
difficulties in controlling the occlusal scheme.
MANDIBULAR SINGLE DENTURE:
3- Minimal denture foundation area
4- Fracture.
5- Tooth wear.
6- Tissue abuse.
MANDIBULAR SINGLE DENTURE:
The alternative line of treatment plan for such patient could be either:
1- Extraction of remaining teeth and complete upper and lower
denture are constructed.
MANDIBULAR SINGLE DENTURE:
Options other than extraction of maxillary dentition For Preservation of the Residual Alveolar
Ridge
1. Maximize denture base coverage
2. Minimized occlusal forces
3. Preprosthetic surgery
4. Retention of key roots
5. Use of osseointegrated implants
6. Temporary soft liners replaced on a regular basis
7. Permanent soft liners
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
A Combination Syndrome by Kelly (1972): destructive problems, that
may be encountered as a result of long term use of a mandibular
distal extension partial denture against a complete maxillary denture.
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
This syndrome consists of:
1. Loss of bone from the maxillary anterior edentulous ridge.
2. Down growth of the maxillary tuberosities .
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
This syndrome consists of:
3. Papillary hyperplasia of the tissues of the hard palate.
4. Extrusion of the lower anterior teeth and,
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
This syndrome consists of:
5. Loss of bone beneath the removable partial denture bases.
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
It usually has six associated changes:
1. Loss of vertical dimension of occlusion.
2. Occlusal plane discrepancy.
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
It usually has six associated changes:
3. Anterior spatial resorption of the mandible.
4. Development of epulis fissuratum .
5. Poor adaptation of the prosthesis
6. Periodontal changes.
COMBINATION SYNDROME AND ASSOCIATED CHANGES
(Kelly’s Syndrome)
The Combination Syndrome is a result of three main factors:
1. The great magnitude of forces involved from lower anterior teeth.
2. The unsuitability of the denture foundation to resist them
3. The particularly unfavorable occlusal relationship
Sincerely :
Dr. Hussein A. Hady Hussein