RPD LAB CHAPTER 4 MOVEMENTS

-Horizontal

-Sagittal

-Frontla planes

3 fundamental planes

3 fundamental planes

this is used to describe potentiak movement of a RPD

Linear axis

INtersection of any two planes results into?

Sagittal

in the first movement what is its plane:

TRansverse

in the first movement what is its axis:

Most posterior abutment

in the first movement what is its fulcrum :

-Vertical tissueward to denture base

-Vertical tissue away from the denture base

in the first movement what is its mvoement:

FRontal

in the Second movement what is its plane:

Sagittal

in the Scond movement what is its axis:

LOngitudinal axis over the crest of the residual ridge

In the second movement, what is its fulcrum

ROtary direction about the reisdual ridge

in the Second movement what is its movement:

Horizontal plane

in the third movement what is its plane:

Vertical

in the third movement what is its Axis :

Imaginary vertical axis located near the center of the dental arch

in the third movement what is its fulcrum:

HOrizontal rotary direction about the arch midline

in the third movement what is its movement:

• Length of edentulous span

• Quality of residual ridge

• Clasp flexibility

• Clasp design

• Materials used in clasp construction

• Surface characteristics of abutment

• Occlusal harmony

FACTORS INFLUENCING STRESS TRANSMITTED TO ABUTMENT TEETH

Length of edentulous span

IN influencing stress to abutment teeth, this is when the longer the edentulous span is, the longer the denture base will be, and the greater the leverage force transmitted to the abutment teeth will be. For each distal extension base, the fulcrum is lcoated at or near the occlusal rest on the msot posterior abutment

Broad ridges with parallel sides

In influencing stress to abutment teeth, what type of ridge permits the use of denture bases with longer vertical surfaces

1mm

In influencing stress to abutment teeth, how much mm in thickness of a healthy mucoperiosteum allows bearing of greater functional load

Wrought-wire retentive clasp

in clasp flexibility, what type of clasp is recommended for chosen class I and class II applications

CHromium based alloy

clasp cosntructed of a _________________ alloy will normally exert a greater load on the abutment than will a gold-based alloy

-Lever

-Incline plane

-Wedge

simple machiens that affect RPD design

-Rigid bar

-Fulcrum

A lever consists 2 components

First class

THis class of lever has the potential to be very efficient

Second class

THis class of lever is less efficienct

Third class

THis class of lever is the least efficient

Incline plane

This simple machine is a flat surface set at an angle to a horizontal surface. used to facilitate the movement of objectes by reducing the required force.

WEdge

This machine is made of two inclined planes taht converts force into lateral pressure, useful for cutting or splitting

Wedge

THis machine aids in isolating class II cavities