Introduction to Removable
Partial Prosthodontics
Rola M. Shadid, BDS, MSc
Partial Denture
A prosthesis that
replaces one or more,
but not all of the
natural teeth and
supporting
structures. It is
supported by the
teeth and/or the
mucosa. It may be
fixed (i.e. a bridge) or
removable.
Removable Partial Denture (RPD)
A partial denture that can be removed and
replaced in the mouth by the patient.
Can be interim RPD (all-resin) or definitive
cast framework RPD
Interim Rmovable Partial Denture
(Provisional; Temporary)
A denture used for a
short interval of
time to provide:
a. esthetics,
mastication, occlusal
support and
convenience.
b. conditioning of the
patient to accept the
final prosthesis.
Retention:
Resistance to removal from the tissues or
teeth
Stability:
Resistance to movement in a horizontal
direction (anterior-posteriorly or mediolaterally
Support:
Resistance to movement towards the
tissues or teeth
Abutment: A tooth
that supports a
partial denture.
Retainer: A
component of a
partial denture that
provides both
retention and
support for the
partial denture
Classification of
Partially Edentulous
Arches
Major Categories of Partial Tooth
Loss
Tooth- and tissuesupported space
Tooth-supported
space
Requirements of an Acceptable
Classification…..
 should permit immediate visualization of
the type of partially edentulous arch that
is being considered.
 should permit immediate differentiation
between the tooth-supported and the
tooth- and tissue-supported removable
partial denture.
 should be universally acceptable.
Classification of Partially Edentulous
Arches
 To assist our management of partially
edentulous patients
 Many classifications have been proposed but
Kennedy classification is the most widely
accepted
 Class II RPD
Kennedy classification
 Was proposed by Dr. Edward Kennedy in
1925
 Like Bailyn & Skinner classification, it
classifies the partial edentulous arches in a
manner that suggests principles of design for
a given situation
Kennedy classification
 He classified the partial edentulous arches
into four basic classes
 The other edentulous areas that donot
determine the class are considered as
modification spaces
Kennedy classification
Class I: Bilateral edentulous areas located posterior
to natural teeth
Class II: A unilateral edentulous area located
posterior to remaining natural teeth
Class III: A unilateral edentulous area with natural
teeth remaining anterior and posterior to it
Class IV: A single, but bilateral (crossing the midline)
edentulous area located anterior to remaining
natural teeth
Applegate’s Rules for Applying
the Kennedy Classification
Rule 1: the classification should follow, not precede
extractions.
Rule 2: if a 3rd molar is missing and not to be replaced,
it’s not considered in the classification.
Rule 3: if a 3rd molar is present and to be used as an
abutment, it’s considered in the classification.
Rule 4: if a 2nd molar is missing and not to be replaced,
it’s not considered in the classification.
Rule 5: the most posterior area always
determines the classification.
Rule 6: edentulous areas other then those
determining the classification are referred to as
modifications and are designated by their
numbers.
Rule 7: the extent of the modification is not
considered, only the number of additional
edentulous areas.
Rule 8: there are no modification areas in a K
Class IV.
What are the Available Options
to Manage This?
What are the Available Options
to Manage This?
What are the Available Options
to Manage This?
Missing Teeth May Be Replaced By
One of Three Prosthesis Types: *
1. An implant-supported fixed partial
denture
2. A tooth-supported fixed partial denture
(FPD)
3. A removable partial denture (RPD)
4. No replacement
Alternatives to RPD (Treatment
Options)
1. Implant-supported prosthesis – most
costly, closest replacement to natural
dentition, less costly over long term
2. Fixed partial denture – requires
abutments at opposite ends of edentulous
space, more expensive than RPD, must
grind down abutments, flexes and can fail
if too long
3. No treatment
No Treatment
 If a patient presents with a long-standing
edentulous space into which there has been
little or no drifting or elongation of the
adjacent or opposing teeth, the question of
replacement should be left to the patient's
wishes.
 If the patient perceives no functional,
occlusal, or esthetic impairment, it would
be a dubious service to place a prosthesis.*
No Treatment (Shortened Dental
Arch)
 Most patients can
function with a
shortened dental
arch (SDA)
 RPD doesn’t usually
improve function in
shortened dental
arch cases
Shortened Dental Arch
 Requires anterior
teeth + 4 occlusal
units (symmetric
loss) or 6 occlusal
units (asymmetric
loss) for acceptable
function Opposing PM =1
unit, opposing
molars = 2 units
Indications of RPD
A removable partial denture should
be considered only when a fixed
restoration (either tooth-supported
or implant-supported) is
contraindicated
Indications of RPD * (Span
Length)
 Edentulous spaces greater than two
posterior teeth, anterior spaces greater
than four incisors, or spaces that include
a canine and two other contiguous teeth;
i.e, central incisor, lateral incisor, and
canine; lateral incisor, canine, and first
premolar; or the canine and both
premolars.
Indications of RPD (Distal
Extension Situations)
 An edentulous space
with no distal
abutment will usually
require an RPD,
especially when
implant treatment is
not feasible for the
patient. *
Distal Extension Situations
 To minimize the leverage
effect, the pontic should be
kept as small as possible,
more nearly representing a
premolar than a molar .
 There should be light
occlusal contact with
absolutely no contact in any
excursion.
 The pontic should possess
maximum occlusogingival
height to ensure a rigid
prosthesis.
Indications of RPD (After Recent
Extractions)
Replacement of teeth after recent extractions often
cannot be accomplished satisfactorily with a fixed
restoration. When relining will be required later
or when a fixed restoration using natural teeth or
implants will be constructed later, a temporary
RPD can be used.
Indications of RPD (Abutment
Alignment)
Tipped teeth adjoining
edentulous spaces
and prospective
abutments with
divergent alignments
may lend themselves
more readily to
utilization as RPD
rather than FPD
abutments, if implant
therapy is not
amenable.
Indications of RPD (Need for
Effect of Bilateral Stabilization)
 Periodontally weakened primary
abutments may serve better in retaining a
well designed removable partial denture
than in bearing the load of a fixed partial
denture. *
Avoid Unilateral RPD
Indications of RPD (Abutment
condition)
 Teeth with short clinical crowns or
teeth that are just generally short
usually will not be good FPD
abutments.
 Unusually sound abutment teeth
Indications of RPD (Abutment
Condition)
An insufficient
number of
abutments may
also be a reason
for selecting a
removable rather
than FPD, if
implant therapy is
not amenable.
Indications of RPD (Excessive
Loss of Residual Bone)
 If there has been a
severe loss of tissue
in the edentulous
ridge, an RPD can
more easily be used
to restore the space
both functionally
and esthetically.
Gingival Reconstruction with
FPD
Indications of RPD ( Economic
Considerations)
 Economics should not be the sole criterion in
arriving at a method of treatment.
 When for economic reasons, complete treatment is
out of the question and yet replacement of missing
teeth is indicated, the restorative procedures
dictated by these considerations must be described
clearly to the patient as a compromise and not
representative of the best that modern dentistry
has to offer. *
Combination of RPD and FPD
Usually, any missing
anterior teeth in a
partially edentulous
arch are best replaced
by means of a fixed
restoration. Then, the
replacement of missing
posterior teeth is made
with an RPD .*
Combination of RPD and FPD
When an edentulous space
that is a modification of
either a Class I or Class
II arch exists anterior to
a lone-standing
abutment tooth, the
splinting of this
abutment to the nearest
tooth by FPD is
mandatory. *
Combination of RPD and FPD
Eliminate all but one
posterior edentulous
space per quadrant
by using an FPD to
simplify the RPD
design.
Removable Partial Denture
 Dry mouth poor
RPD risk
 Limited patient
finances
 Acceptable oral
hygiene
 Reliable recall
candidate
 Treatment
simplification
 Advanced age
 Systemic health
problems
 More adaptable to
dentition in
transition to
edentulous state
Conventional Tooth-Supported FPD
 Dry mouth high
caries risk
 Muscular
discoordination
 Mandibular tori
 Palatal soft tissue
lesions
 Large tongue
 Exaggerated gag
reflex
 Unfavorable attitude
toward RPD
 Patient can't cope
with aging, tooth loss
 Favorable opposing
occlusion
 Periodontally
weakened natural
dentition may permit
FPD in less than
optimal situations
Components of a Typical RPD




Major connectors
Minor connectors
Direct retainers
Indirect retainers (if
the prosthesis has
distal extension bases)
 One or more bases,
each supporting one to
several replacement
teeth
(a) Major Connector:
The unit of an RPD
that connects the
parts of one side of
the dental arch to
those of the other
side.
 Its principal
functions are to
provide unification
and rigidity to the
denture.
(b) Minor Connector:
A unit of a partial
denture that connects
other components (i.e.
direct retainer,
indirect retainer,
denture base, etc.) to
the major connector.
 The principle
functions of minor
connectors are to
provide unification
and rigidity to the
denture.
(c) Direct Retainer:
 A unit of a partial
denture that provides
retention against
dislodging forces.
 A direct retainer is
commonly called a
'clasp' or 'clasp unit'
and is composed of
four elements, a rest,
a retentive arm, a
reciprocal arm and a
minor connector.
(d) Indirect Retainer:
 A unit of a Class I or
II partial denture
that prevents or
resists movement or
rotation of the
base(s) away from
the residual ridge.
 The indirect retainer
is usually composed
of one component, a
rest.
(e) Denture Base:
The unit of a partial
denture that covers
the residual ridges
and supports the
denture teeth.
References
 McCracken’s Removable Prosthodontics, 11th
Edition 2005 by McGivney GP, Carr AB.
Chapter 2 and 3
 McCracken’s Removable Prosthodontics, 11th
Edition 2005 by McGivney GP, Carr AB.
Chapter 12 Diagnosis and Treatment Planning
P 215-220