100008874 (1).ppt

CONTENTS
 Introduction
 Definition
 Problems associated with single complete denture
 Diagnosis and treatment planning
 Various combinations of single complete denture

 Common occlusal disharmonies
 Methods used to achieve harmonious balanced occlusion
 Occlusal materials for single complete denture
 Changes caused by RPD opposing maxillary complete
denture
 Conclusion
 References

INTRODUCTION :
 The single complete denture opposing all or
some of the natural dentition is not an uncommon
occurrence.
 Causes for the loss of teeth from the dental
arches like periodontal problems, dental caries
and trauma.
 The incidence of tooth loss is more in maxillary
arch compared to mandibular arch
 The single complete denture should be given for
reasons like mastication and esthetics.

DEFINITION :
 Single complete denture is a prosthesis which
replaces the lost natural teeth and its associated
structures functionally and esthetically as a
single unit which opposes all or some of the
natural teeth.
The primary consideration for continued denture
success with a single conventional complete
denture is the preservation of that which remains

Indications
Remaining Natural teeth are in good
periodontal health.
A partially edentulous arch in which the
missing teeth have been or will be replaced
by a removable partial denture.
An existing single complete denture

Diagnosis and treatment
planning:
 The commonly sited long term goal in
Prosthodontics is the preservation of that
which remains.
 This demands an appreciation of occlusal
mechanics.

Problems:
1. Occlusal forces
2. Occlusal form of the natural teeth
3. Support for the denture base
4. Inter maxillary relations:

1. Occlusal forces
 These forces have been recorded as high
as 198 lbs on a single molar tooth.
 This is in contrast with the forces which a
complete denture - 26 lbs

2. Occlusal form of the natural
teeth
 The occlusal form of the remaining natural
teeth will dictate the occlusion of the
denture
 The natural teeth may be supra erupted or
tilted and there cusps may be high and sharp.
 Denture will constantly be thrust or dragged
horizontally on the ridge.

3. Support for the denture base:
 Denture base should have the maximum
extension within the functional anatomic
limits
 Lower complete denture opposing upper
natural teeth should be normally avoided.

4. Inter maxillary relations:
 When upper complete denture is being
made to occlude with lower natural teeth,
an error may be made in recording the
vertical dimension
 The labio- lingual thickness of the wax rim,
will usually not allow the lower incisor to
close beyond the occlusal surface
 Increased vertical dimension may be
recorded

Occlusal problems and fracture of denture base account
for structured difficulties and may result from one or all of
the following.
 Occlusal stress on the maxillary denture and the
underlying edentulous tissue from teeth and musculature
accustomed to opposing natural dentition.
 The position of the mandibular teeth which may not be
properly aligned for the achievement of bilateral balance
for stability.
 Flexure of the denture base

COMBINATIONS:
 Upper single complete denture opposing complete
set of lower natural teeth.
 Lower single complete denture opposing complete
set of upper natural teeth.
 Single complete denture opposing natural teeth
with a removable partial denture.
 A single complete denture opposing natural teeth
with a fixed partial denture.
 A single complete denture opposing an already
existing complete denture

Single complete denture (Maxillary)
to oppose natural mandibular teeth:
 More frequently encountered than the single
mandibular denture
 The occlusal forms of the natural teeth act as a
guide in selecting the occlusal form for the
maxillary posterior teeth
 However if the natural teeth are abraded
monoplane form may be the choice

 Some times the position of mandibular
teeth will not allow the maxillary
anterior teeth to be positioned in an
esthetically acceptable manner or for
balanced occlusion.

This problem may be solved as follows.
Reposition of the natural teeth with orthodontic
procedures
Alter the clinical crowns of the teeth by
grinding or with restoration.
Accept balanced occlusion with the jaws in
the terminal relation and not in the eccentric
position

 The mandibular arch may present two
planes of occlusion,
 An anterior plane and
 A posterior plane
The posterior teeth have extruded and
inter ridge space would be less.

 To prepare this mouth it requires extensive
restorative procedures in mandibular arch
and possibly surgery in the maxillary arch.
 To proceed with complete maxillary
denture procedures without first preparing
the environment into which the artificial
teeth will be placed is to invite trouble.

Mandibular denture to oppose
natural maxillary teeth:
 It usually happens as a result of either surgical
or accidental trauma i.e. irradiation or accident
or gunshot.
 Three factors in particular must be carefully
evaluated.
Preservation of the residual alveolar ridge
Necessity for retaining maxillary teeth
Mental trauma

Preservation of the residual alveolar
ridge
 The force of jaw closure with natural teeth is
greater than that with complete denture and
greater the force the more the pressure
which a contributing factor to bone
resorption

Necessity for retaining maxillary
teeth:
 The maxillary dentition may be needed to
retain prosthesis.
 This situation is usually associated with
congenital defects such as cleft palate or
stoma resulting from surgical or accidental
trauma.

Mental trauma
 A mental state exists when the patient loses the mandibular teeth,
removal of the remaining maxillary teeth may be more than he or she
can endure mentally.

Complete maxillary denture to oppose
a partially edentulous mandibular arch
with fixed or removable prosthesis :
 First it must be determined if the fixed
restorations are acceptable if they can be made
acceptable or if they must be rejected.
 When the restorations are acceptable one must
then decide what occlusal concept will be
pursued
 Teeth in single complete denture are on a
movable base and even though they function
against natural teeth they will function as a unit.

When there is a removable partial denture,
it must be evaluated critically.
 The occlusal plane
 Tooth arrangement for occlusion
 Esthetics and material composition of the
teeth
Treatment plan is or should be formulated
for both arches at the same time

Single complete denture to
oppose an existing complete
denture:
In this situation this following
factors must be considered.
Duration of existing denture
Was the denture an immediate insertion
at the time of teeth removal
These two factors are directly related to
the extent of bone resorption.

Does the denture meet the requirements of an
acceptable denture?
Condition of opposing arch in relation to the
existing denture.
A most serious consideration is the fact that
the dentist assumes the responsibility for both
dentures as soon as he accepts the patient for
treatment of the single complete denture.

COMMON OCCLUSAL
DISHARMONIES
 The most common occlusal adjustments involve the
anterior teeth and the last molar
 Frequently natural lower incisors and cuspids are very
long and there should be ground as much as is practicable
 If the molars are not severely lilted they may be reshaped
by selective grinding
 Stephen’s recommends that the distal half of the occlusal
surface should be ground flat and the denture teeth set to
occlude with only that area, leaving mesial cusps out of
contact.

 The ideal treatment is to restore the tilted
molar with cast gold crowns, onlays or fixed
bridge if a large edentulous space exists
mesial to the molars.
 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 molar.

 If the molar are severely tilted forward and
supraerupted the modification is not
possible, extraction is necessary.
 Another disharmony exists when
insufficient mandibular teeth are left to
occlude with a complete maxillary denture

Methods used to achieve
harmonious balanced occlusion:
Many techniques have been described
but all of them basically fall into two
categories.
Functional chew in techniques:
Articulator equilibration technique:

Functional chew in
techniques:
 Stransbury described the first functional chew in
technique in 1928
 He suggested using a compound maxillary
occlusal rim trimmed buccally and lingually so
that the occlusion is free in lateral excursions.
 Carding wax is then added to the compound rim
and the patient is instructed to perform eccentric
chew movements.

 The carding wax as slowly molded to the
functional movements while the compound in
the central fossa act as a guide to preserve
the vertical dimension.
 The generate occlusal rim is now removed
from the mouth and stone is vibrated into the
wax paths of the cusps and without
separating them both are mounted on the
articulator
 The denture teeth are set according to the
lower cast of the patients teeth

 After the esthetics has been approved at the
try-in, the lower cast is removed and lower
chew in record is secured to the articulator
 All interfering spots are carefully ground until
the incisal guide pin prevents further closure.
 Thus in centric and eccentric movements
maximum bilateral balanced occlusion will
have been established.

 VIG described as similar technique in which
he recommended the use of a fin of resin
placed into the central grooves of the lower
posterior teeth, instead of using compound as
mentioned by starsbury.
 The resin fin maintains the vertical dimension
and also helps diagnostically locate
interfering lower cusps
 In eccentric movements the lower cusp tips
are ground until equal contacts occur
between the teeth and the resin

 The fin is then built up using a soft wax and a
functional path is generated.
 Sharry’s technique
Lateral and protrusive chewing movements are
made so that the wax is abraded generating the
functional paths of the lower cusps.
This is continued until the correct vertical
dimension has been established.

 Rudd suggests a technique similar to
starsbury’s
 A thickness of recording matrix made up of
3 sheets of medium and pink base plate
wax and two sheets of red counter wax in
added to the buccal and lingual surface of
this compound rim.

Articulator equilibration
technique:
 If the denture bases lack stability or if the patient
is physically unable to perform a chew in record
the articulator equilibration method is preferred
 First the upper cast is mounted on the articulator
using a face bow with an orbital pointer
 The lower cast is related to the upper by a
centric inter occlusal record at an acceptable
vertical dimension.

 If the denture teeth apex to be placed too far to
buccal when articulated with the lower buccal
cusp, they are rest to oppose the lingual cusps.
 Once the holding cusps have been selected the
inclines of the remaining cusps are reduced and
vice-versa
 This allows for a cusp to fossa relationship
between the upper and lower teeth in centric .

 At the time of wax try in eccentric records are
made and the condylar inclinations are set on
the articulator
 The upper posterior teeth are arranged to be as
close to being balanced as is possible at this
time.
 After the denture has been processed it is again
related to the mounted lower cast with a new
centric intra-occlusal record.

The condylar inclinations previously
determined are reset on the articulator.
Once the centric holding cusps are
established by selective grinding, eccentric
balance is achieved.
This is simply accomplished by selectively
grinding the interfering buccal and lingual
cuspal inclines of the upper teeth.
Once the centric contacts have been
established it is advisable to use two colors of
articulating paper. One colour to mark the
centric contacts and other to mark the
eccentric contacts.

 The eccentric contacts are selectively
ground until a relatively continuous area of
contact is noted on the buccal and lingual
cuspal inclines of the upper teeth.

Types of teeth:
The most important aspects are to transmit
the occlusal forces vertically.
 Non – anatomic teeth
 Anatomic teeth

Non – anatomic teeth
 If the cusps of the natural teeth have been
reduced either naturally or artificially to such a
degree that their occlusal surface are fairly flat,
then non anatomic teeth maybe used on the
denture.
 These teeth have flat occlusal surfaces with
fissures and spillways carved into them which
help to provide an effective masticating surface.

Anatomic teeth:
 If the cuspal form of the lower teeth has been
retained anatomic teeth can be used
 These should be arranged with a cusp to fossa
relation.
 A small space distal to the cuspid looks quite
natural in an upper denture, spaces between the
posterior teeth provide extra channel for the
escape of food from the occlusal surfaces

Artificial tooth materials
 The materials available for occlusal
posterior tooth forms are
Porcelain
Acrylic teeth
Gold
Acrylic resin with amalgam stop
IPN

 Porcelain teeth wear slowly therefore the
occlusal vertical dimension is maintained
however they are predisposed to fracture and
chipping when opposed by natural teeth and
are more difficult to equilibrate.
 Also they cause rapid wear of opposing
natural teeth.
Porcelain teeth:

Acrylic resin teeth
 Since acrylic resin teeth cause no wear of the
opposing natural teeth they are the easiest to
equilibrate
 They are the teeth of choice.
 The major disadvantage of resin teeth is there
wear, which result in loss of vertical dimension

Gold occlusal:
 The best material for an artificial occlusion
opposing the natural teeth is gold
 A technique described by Wallace in 1964
 The occlusal surfaces of the posterior acrylic
denture teeth are then reduced by about 1mm
and a central channel is cut posteriorly along
them
 The wax patterns are cast in gold and cemented
with self cure acrylic resin.

Acrylic resin with amalgam
stops:
 This method is established by Frank R.
Lauciello.
 After the acrylic teeth have been balanced,
occlusal preparation are made in the acrylic
teeth, extending it include as much of the
articulating paper tracing as is possible.
 Amalgam is condensed into the preparation and
the articulator is gently closed, going side to side
and back and forth until the incisal guide pin is
again flush with the guide table.

 This material consist of an unfilled,
highly cross linked inter penetrating
polymer network.
 A three year clinical study by ogle and his
colleagues, has determined the wear of
new material to be significantly less when
compared to acrylic resin teeth.
Inter penetrating polymer net work
(IPN)

Changes caused by mandibular
removable partial denture apposing
maxillary complete denture:
 Another problem is combination syndrome.
 The syndrome is characterized by
Maxillary anterior ridge resorption
Palatal papillary hyperplasia
Enlargement of maxillary tuberosities
Supra eruption of lower anterior teeth
Resorption of mandibular posterior ridge

CONCLUSION:
The problems involved in providing comport,
function, proper esthetics and retention is a
vigorous challenge for practicing dentist. The
damage to the edentulous ridge and inability to
wear the denture may be avoided by good
prosthetic treatment which includes adequate
denture base, correct jaw relation record and
proper occlusion.

REFERENCES :
 Prosthodontic treatment for edentulous patients -
Boucher
 Essentials of complete denture Prosthodontics – 2nd
edn. Sheldon Winkler
 Syllabus of complete denture – Heartwell
 Complete denture Prosthodontics – Sharry
 Changes caused by a mandibular RPD opposing a
maxillary C.D. – Ellsworth Kelly J. Prosthet. D. 27;
140-150: 1972.
 Single complete denture – Charles W. Ellinger J.
Prosthetic. D. 26 ; 4-10 : 1971.

 CD’s opposing natural teeth - Robert W. Bruce JPD 26;
448 –55: 1971.
 Occlusion and single denture – Kenneth D. Rudd JPD
30; 4-10: 1973.
 The maxillary CD opposing natural teeth: the problems
and some solutions – Alex Koper JPD 57; 704 –07:
1987.
 The maxillary CD opposing mandibular bilateral distal
extension partial denture – Sounder RT JVD 41(2); 124-
28: 1979.
 Diagnosing functional CD fractures – Schineder L.
Robert 54; 804-14: 1985.

100008874 (1).ppt

More Related Content

Similar to 100008874 (1).ppt (20)

More from Aswitha Ganapathy (12)

Recently uploaded (20)

100008874 (1).ppt