RPD Introduction and Classifications

Study Notes

RPD Overview

A removable partial denture (RPD) is used to replace some teeth in partially edentulous arches, easily inserted and removed by the patient.

Indications for Fixed Dental Prosthesis

Short spaces between teeth
Anterior spaces requiring modification
Aesthetic considerations

Indications for Removable Partial Denture

Long edentulous areas unsuitable for fixed prostheses
Need to restore tissue contours
Lack of adequate periodontal support
Compromised abutment teeth (clinical crown height, sound structure, position issues)
Need for cross-arch stabilization
Requirement for distal extension bases
Concerns for anterior aesthetics
Patient's physical/emotional issues preventing the use of fixed options
Increased ease of plaque removal
Economic considerations

Requirements of RPD Design

Retention achieved through clasps
Stabilization via cross-arch support
Support from denture base, major connectors, and occlusal rests

Surveyed Crown

Abutments for RPDs, typically full metal or metal-ceramic, designed for proper reciprocation and rests.
Rests and guiding planes (GPs) must be metal.

Occlusal Rest

Consists of horizontal and vertical components.
Horizontal part rests on abutment tooth, transferring masticatory forces.
Vertical part connects to the partial denture base.

Guiding Planes

Parallel surfaces on teeth or fixed prostheses to direct RPD placement.
Can be natural or created, often prepared on teeth near the edentulous space.

Clasp Types

Bar Clasp: Retentive tip approaches undercut from below the survey line (infrabulge/clasp).
Circumferential Clasp: Retentive tip approaches from above the survey line (suprabulge/clasp).

Kennedy Classification

Utilized for partially edentulous situations; class is determined by the most posterior edentulous area.
Class I: Bilateral posterior edentulous areas.
Class II: Unilateral posterior edentulous area.
Class III: Unilateral edentulous area with surrounding natural teeth.
Class IV: Bilateral area anterior to remaining natural teeth, crossing the midline.

RPD Classification Rules

Classification follows tooth extractions affecting the initial layout.
Missing 3rd molars not to be replaced are excluded from classification.
3rd molars can be included if used as abutments.
Missing second molars not considered if not planned for replacement.
Modification areas are numbered but do not include extent.
No modification areas allowed in Class IV arches.

Common and Least Common Classifications

Most prevalent classification (72%): Classes I & II, or Class I, Mod 2, Class II, Mod 1.
Least common classification (2.5%): Class II at midline and Class II, Mod 2.

Tooth-Tissue Borne Classifications

Class I and II are considered tooth-tissue borne.

Description

This quiz covers the fundamentals of removable partial dentures (RPD) and their classifications. It includes key terms and definitions essential for understanding RPD indications, as well as fixed dental prosthetics. Perfect for dental students and professionals looking to test their knowledge on this important topic.