RPD Introduction and Classifications

Questions and Answers

What is a RPD?

A removable denture that replaces some teeth in a partially edentulous arch; the removable partial denture can be readily inserted and removed from the mouth by the patient.

What are indications for fixed dental prosthesis?

Anterior modification spaces (correct)

Esthetics (correct)

Costs too high

Short tooth bound space (correct)

What are indications for a removable partial denture?

Problems with dental implants

Unilateral edentulous area (correct)

Lack of clinical crown height (correct)

Need to restore soft and hard tissue contours (correct)

What are the 3 requirements of RPD design?

Retention, Stabilization, Support Signup and view all the answers

What is a surveyed crown?

Crowns that are used as abutments of RPDs, made to have proper reciprocation, grooves, rests, and undercuts. Signup and view all the answers

What is an occlusal rest?

An occlusal rest consists of a horizontal portion that rests on the abutment tooth and a vertical component connecting to the denture base. Signup and view all the answers

What are guiding planes?

Two or more vertically parallel surfaces on abutment teeth that help in the path of placement and removal of RPD. Signup and view all the answers

What is a bar clasp?

A type of clasp where the retentive tip approaches the undercut from below the survey line. Signup and view all the answers

What is a circumferential clasp?

A clasp where the retentive tip approaches the undercut from above the survey line. Signup and view all the answers

What is the Kennedy Classification?

A classification system for partially edentulous situations consisting of four classes. Signup and view all the answers

What is the most common Kennedy Classification?

Class I Signup and view all the answers

What is the least common Kennedy Classification?

Class II (at midline) Signup and view all the answers

Which Kennedy Classifications would be tooth-tissue borne?

Class II Signup and view all the answers

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.