different treatment options in kennedy class iv

1. Kennedy class IV partial dentures
By
MOHAMMAD AL-GHRAISI
Assistant-lecture
Misrata university

2. Management of classIV
Definition: A single saddle lies entirely anterior to the abutments.
 This class has no modifications
 The length of the saddle may vary from a single tooth to include posterior
teeth in both sides of the jaw.
 Such dentures are commonest in the maxillary arches.
 The most frequent mandibular anterior saddle denture is the one that
replaces the four incisors lost through periodontal disease.
 May occur in childhood and adolescence.

3. Treatment options of classIV
In children
Spoon denture
Modification of
spoon denture
In adults
Short
span
Long
span
 Single implant
• Implant
supported
fixed prosthesis
Fixed
bridge
Composite
bonded
bridges
RPD
Implant
supported
fixed
prosthesis
RPD

4. The treatment of children
Spoon denture
• The spoon denture is a mucosa-borne partial denture which is constructed
either in acrylic resin or in cast metal
• The denture should cover a large area of the hard palate to overcome the
problem of poor retention. It should also be preferably extended to junction
between the hard and soft palate in order to:
 Obtain retention by physical means as adhesion.
 Obtain an adequate posterior palatal seal necessary for denture retension.
 Benefit from the upward pressure of the tongue causing seating of the
denture against vertical displacement.
• The borders of denture should be 3-4 mm away from the gingival margin to
avoid caries and gingivitis.

5. Modifications of spoon denture
spoon denture could be modified to improve retention and stability in the
following manner:
1. Spoon denture modified by use of Adams clasps
The palatal plate is extended laterally above the survey line of the first
molars.
2. T-shaped cobalt chromium denture
The spoon dentures in the form of a combination of an anterior cast cobalt
chromium base and posterior acrylic resin extension carrying an Adam crib
clasp for providing retention

6. Factors affecting success of spoon dentures
1. Nature of the mucosa
the presence of firm mucosa of adequate thickness rather than thin
mucosa that is usually encountered in children provides better denture
retention.
2. Form of the hard palate
• Large palate provides better retention by adhesion
• Palates with steep slopes offer more resistance to lateral forces and
provide denture stability
3. Use of anterior flange that helps to resist downward dispalcement of
the restoration
4. Degree of vertical overlap
the presence of deep vertical overlap associated with a small horizontal
overlap resulting due to partial edentulism induces stresses on the denture
during incision.

7. Treatment of adult patients
four lines of treatment are proposed for the
treatment of unilateral bounded areas. These
are:
1. Implant supported prosthesis
2. Fixed bridges
3. RPD
4. Composite bonded bridges

8. IMPLANT OPTION

9. Class IV skeleton design
Class IV skeleton design is an alternative line of treatment to
fixed bridge. It is indicated in the following conditions:
• Cases where marked bone resorption necessitates the addition of an
anterior flange to restore esthetics and provides lip support.
• Patients who refuse extensive preparation required to prepare the
abutments supporting the bridge.
• Cases having long, markedly curved edentulous span because this may
add excessive stresses on abutments.

10. Generally two skeleton design were proposed:
1. the first uses an anterior clasping system in the form of I bar clasp located
on the canine and a re-enforcing circumferential aker clasp located on the
first premolar. This clasping system has the disadvantage of placing
excessive stresses on the canine and bad esthetics. The canines used
should be strong and should have long well formed roots to resist torque.
2. The second design uses a posterior clasping system in the form of an
embrassure clasp or multiple clasp located as far posteriorly as possible.
This system is more favorable because it provides more direct and indirect
retention. It also esthetically more satisfactory and more hygienic. The
canines are also saved from excessive torque placed on them.

11. The general design for posterior clasping system employed in either upper or
lower classIV consist of:
a. Denture base
a combination metal-acrylic base is usually indicated to provide esthetics and
to allow for future relining when bone resorption occurs .
b. Supporting rests
support is preferably provided by cingulum rests located on adequatley
prepared rest seats on the canine teeth.
c. Clasps
embrassure or aker clasp located posteriorly preferably on the first molar
teeth are used. The more posteriorly located the clasps the more will be the
retention of the appliance.

12. d. Major connector
• for upper class IV , anterior plate or anteroposterior platal plate may be
used
• For lower class IV, lingual bar connector is used.
e. Indirect retainer
• indirect retention to counteract around the fulcrum axis is encountered
by the rests of posterior clasps.
• Indirect retention to counteract displacement of upper dentures resulting fro
heavy weight of the cast metal appliance is counteract by proper extension
of the labial flange and by the labial flange designed to engage a soft tissue
undercut