Removable Partial Denture (RPD)

REMOVABLE PARTIAL DENTURE RPDs are components of prosthodontics ( branch of Dentistry) pertaining to the restorations and maintenance of oral function, comfort, appearance, and health of the (pt) by replacement the missing teeth and craniofacial tissues with an artificial substitute.

INDICATIONS FOR REMOVABLE PARTIAL DENTURES

No abutment tooth posterior to edentulous space (Free end edentulous area)
Long edentulous bounded span, too extensive for fixed restoration
Periodontally weak teeth not sufficiently sound to support fixed- partial denture.
With excessive loss of residual bone, the use of labial flange or need to restore lost tissues.
After recent extraction, usually done only to improve esthetics, or for patient satisfaction.
Need of bilateral bracing (cross arch stabilization)
Young age (less than 17 years).
Enhancing esthetics in anterior region, by the use of translucent artificial teeth instead of dull fixed partial denture pontic.
Economic considerations, attitude and desire of the patient.

OBJECTIVES OF REMOVABLE PARTIAL DENTURES

Elimination of oral disease.
Preservation of the health and relationship of the teeth, and the health of the oral and para-oral structure.
Restoration of oral function (comfort, esthetic, speech).

CLASSIFICATION OF PARTIALLY EDENTULOUS ARCHES

The most familiar classification are those proposed by Kennedy, Cummer, and Bailyn, Beckett,
The recent classification has been proposed for partial edentulism that is based on diagnostic criteria.

KENNEDY CLASSIFICATION

4 basic classes.
Edentulous areas other than those determining the basic classes were designated as modification spaces

Kennedy referred each additional edentulous areas a modification area,(eg; class I modification, class II modification III)
In class IV, the most posterior space determines the classification. so cannot have modification spaces.

APPLEGATE’S MODIFICATION

Applegate expand kennedy’s classification by adding class 5 and class 6,

Class 5:edentulous area bounded anteriorly and posteriorly by natural teeth,but in which the anterior abutment is not suitable for support.
Class 6:an edentulous areain which teeth adjacent to the space are capable of total support of required prosthesis,this denture hardly required any tissue support,

APPLEGATE'S RULES FOR APPLYING THE KENNEDY CLASSIFICATION

Rule 1 : The classification should follow, not precede extractions.
Rule 2 : If a 3 rd molar is missing and not to be replaced, it is not considered in the classification.
Rule 3 : If a3rd molar is present and not to be used as an abutment, it is not considered in the classification.
Rule 4 : If a 2 nd molar is missing and not to be replaced, it is not considered in the classification.
Rule 5 : The most posterior area always determines the classification.
Rule 6 : Edentulous areas other than those determining the classification are referred to as modifications and designated by their No.
Rule 7 : The extent of the modifications is not considered, only the No. of additional edentulous areas.
Rule 8 : There are no modification in Class IV.

ADVANTAGES OF KENNEDY’S CLASSIFICATION	DISADVANTAGES OF KENNEDY'S CLASSIFICATION
Universally accepted, Most widely used system, It permits immediate visualization of partialy edentulous arch, It allow easy distinction between tooth supported versus tooth and tissue supported prosthesis, It aids in identity and planing the design,	It tells about the spaces but not teeth to be replaced, It does not applicable to in case of single standing tooth, It does not maintain the condition of the abutment teeth

OTHER CLASSIFICATIONS

CUMMERS CLASSIFICATION (1921)
W. BAILYN (1928)
NEUROHRS CLASSIFICATION
FRIEDMANS SYSTEM
OSBORNE and LAMMIE

CUMMERS CLASSIFICATION (1921)

First classification to be recognised by the dental profession
He classified partial dentures than edentulous spaces
Four types
1. Diagonal: 2 retainers diagonally opposite another
2. Diametric: 2 retainers diametrically opposite one another.
3. Unilateral: 2 or more direct retainers on same side.
4. 4. Multilateral: 3 direct retainers on either side.

CHARLES. W. BAILYN (1928)

He emphasized the importance of support for partial dentures.
“A”- Anterior restorations where there were saddle areas anterior to the bicuspids.
“P”- Posterior restorations where there were saddle areas posterior to the canines.

CLASSIFICATION

Class I: Bounded saddle (Tooth supported).
Class II: Free end saddle (Mucosa supported).
Class III: Bounded saddle (More than 3 tooth missing). Example: If all posterior teeth from canines till molars are missing with lateral incisors then the classification is AI P III.

NEUROHRS CLASSIFICATION

Class I:

Variation I:

Posterior missing, Anterior all teeth present.
Posterior missing, some anterior teeth missing.

Variation II

Anterior missing, All posteriors present.
Anterior missing, some posteriors missing.

Class II: Division I has variation 1 and 2.
Division II has variation 1 and 2
This classification is tooth tissue bearing.
Class III is edentulous state.

FRIEDMANS SYSTEM

A- Anterior space
B- Bound posterior space.
C- Cantilever situation or a posterior free end saddle.

OSBORNE and LAMMIE

Class I: Mucosa borne.
Class II: Tooth borne
Class III: Combination of mucosa borne and tissue borne.

MCQs

1. Indication of Removable Partial Denture

Large edentulous space, deep undercut of abutment, not posterior of abutment
Periodontitis of abutment, esthetic for posterior tooth, not posterior of abutment
Large edentulous space, not posterior of abutment, periodontitis of abutment
Deep undercut of abutment, periodontitis of abutment, not posterior of abutment

Answer: C

2. The Kennedy Classification for this cast is

a. Class III mod I
b. Class III mod II
c. Class III
d. Class III mod III
In the picture a mandibular with missing teeth: #36,35,46

Answer: A

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