Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Prostho 2 (RPD) > Lec 3: Components > Flashcards

Lec 3: Components Flashcards

1
Q

Resistance to removal from the tissues or
teeth.

A

Retention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Resistance to movement in a horizontal
direction (anterior-posteriorly or mesio- laterally.

A

Stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Resistance to movement towards the
tissues or teeth.

A

Support

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  • The unit of a removable partial denture 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.
A

Major connector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  • A unit of a partial denture that provides retention against dislodging forces.
  • 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.
A

Direct retainer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  • 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.
A

Minor connector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

4 components of a clasp unit?

A

retentive arm
reciprocal arm
rest
minor connector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

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.

A

Indirect retainer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The indirect retainer is usually composed
of one component, which is the?

A

Rest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  • The unit of the denture that rests on the foundation tissues and to which prosthetics teeth are attached.
  • Attaches the prosthetic teeth to the denture base retention minor connector which attaches the base to the major connector.
A

Denture base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  • Are artificial teeth used on a denture to substitute for natural teeth.
  • By substituting for missing natural teeth, it provide esthetics and masticatory functions.
A

Prosthetic teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

A major connector unites all other
components of a partial denture so that the partial denture acts as one unit.

A

Unification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

– By unifying all elements of a partial
denture the major connector can distribute functional loads to all abutment teeth, so that no one abutment is subjected to extreme loading.
– Unification of the direct retainers with the denture bases aids in distributing forces between both the teeth and the mucosa.

A

Stress distribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  • By uniting one side of the arch to the other bracing elements on one side of the arch can aid in providing stability to the other.
  • This can aid in dissipating twisting and torqueing forces.
A

Cross-arch stabilization (counterleverage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

– Necessary to ensure that the partial denture functions as one unit.
– If the denture flexes, stress distribution and cross arch stabilization can be compromised since different portions of the denture can move independent of the others.

A

Rigidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Major connectors should not enter into undercut areas unless tissue impingement can be avoided by changing the selected path of insertion or by using minor undercut blockout.

A

Non-interference with soft tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

This can be minimized by locating the margins of the connectors at the prescribed distance from the free gingival margin and by taking care that the presence of minor connectors, clasp arms and major connectors does not create “traps” or large concavities where food can collect.

A

Food impaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

– The margins of the major connector should have a smooth transition from connector to tissue so as to minimize the obtrusiveness.
– All line angles and edges should be smooth and rounded.
– Borders should not be placed in locations where they might interfere with speech.
– Bulk should be reduced enough so as not to interfere with speech or appearance, yet thick enough to ensure rigidity.

A

Unobtrusive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

This is the most commonly used mandibular major connector.

It should be used whenever possible unless there are advantages that can be obtained from another major connector.

A

Lingual bar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lingual bar:
Shape:
– ___ on tissue side
– convex or ____ on tongue side
– 1/2 pear shape, with thin edge toward teeth

Size:
– occluso-gingival width = ?
– thickness = ?

Position:
– The inferior border should be as low as the ________ and tissue reflections of the floor of the mouth will permit, as determined by observing functional movements of the tongue.
– The superior border should be
at least _____ below the free gingival margin. For hygienic reasons the superior border should still be kept as far from
the gingival margin as possible.

A

shape:
flat = tissue
tear-drop = tongue
1/2 pear shape

size:
occlusogingival = 4mm
thickness = 1.5-2mm

position:
inferior border = low as lingual frenum
superior border = 3mm below FGM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  • Consists of a lingual bar plus an extension over the cingulum of anterior teeth.
  • This mandibular major connector should only be
    considered in those rare instances where a lingual bar cannot be used.
  • Occurs when there is a high floor of
    the mouth, a prominent lingual frenum or lingual tori that would be impinged upon by a lingual bar, if it was made with adequate height and distance from the free gingival margin.
  • Also advocated for extensive distal extension cases with severe vertical resorption of ridges (i.e. little resistance to horizontal rotational tendencies).
A

Lingual plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  • Must be prepared at each end of the anterior segments of the lingual plate.
  • This prevents excessive forces being directed facially by movements of the distal extension base.
A

Vertical stop/rest area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
  • The connector consists of a lingual bar plus a secondary bar resting above the cingulum of the anterior teeth.
  • The secondary bar supposedly acts as an indirect retainer and performs a role in the horizontal stabilization of periodontally-involved teeth.
  • The performance of these functions is questionable. Additionally, this major connector can create a food trap between the two bars.
  • The use of this type of connector is not encouraged.
A

Continuous bar retainer / Kennedy bar / Double lingual bar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Major connectors in the upper arch should terminate ________ or more from the gingival crest tissues.

A

6 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q
  • Provides maximum rigidity and minimum bulk.
  • The strength of this connector lies in the fact that the anterior and posterior sections are joined together by longitudinal connectors on either side.
  • Each component braces the other against possible torque and flexure.
A

Anterior-posterior palatal strap

26
Q
  • Particularly indicated when maximum tissue support is required.
  • Major connector of choice in long distal extension cases or where six or less anterior teeth remain.
  • It should be selected where the primary abutments are periodontally involved, requiring maximum stress distribution.
A

Full palatal plate

27
Q
  • This type of connector can be Wide or narrow, depending upon its location or the need for strength or support of the denture.
  • Should only be used in tooth supported cases where no other connector can be used. - It is usually objectionable due to its bulk. It should never be used in cases involving distal extensions or replacement of anterior teeth since it must be made to bulky for rigidity.
A

Palatal strap / bar

28
Q
  • A poor connector and should never be used unless absolutely necessary.
  • To be rigid, it must have bulk in the rugae area where the tongue requires freedom. Without sufficient bulk, it becomes flexible and allows movement posteriorly. In distal extension partial dentures where posterior tooth support is nonexistent, movement is particularly noticeable and is traumatic to the residual ridge causing continual irritation during function.
  • Should only be prescribed where the TORUS PALATINUS prohibits the use of other connectors.
A

Anterior palatal plate / Horseshoe-shaped / U-shaped palatal connector

29
Q

Functions of _______:

1) Provide unification and rigidity.

2) Provide stress distribution by transferring stresses
from the major connector to other parts of the partial denture and from the partial denture to the
abutment teeth.

3) Act as bracing elements through contact with
guiding planes opposing the retentive arms.

4) Maintain a path of insertion via contact with guiding planes.

A

Minor connector

30
Q

These connectors should be somewhat triangular shaped in cross section to minimize intrusion into the tongue or vestibular spaces, while still providing adequate bulk for rigidity

A

Minor connectors placed into EMBRASURES between two adjacent teeth.

31
Q

These minor connectors are adjacent edentulous spaces and usually connect the major connector to a clasp assembly as well.

A

Minor connectors that connect the denture base and teeth to the major connector.

32
Q

Tends to be flatter, with more potential rigidity. Conversely, it has been shown provide less retention for the acrylic if the openings are insufficiently large.

A

Mesh type gridwork

33
Q

Has superior retentive potential, but can interfere with the setting of teeth, if the struts are made too thick or poorly positioned.

A

Lattice type gridwork

34
Q

Minor connectors originating from the gridwork in an edentulous area usually take the form of vertical metal plates called __________, that make broad contact with prepared guiding planes.

A

Proximal plates

35
Q

Mandibular distal extension gridworks should have a __________ at their posterior limit. This is an extension of the metal through the relief wax providing direct contact with the ridge. It prevents framework deformation and its consequences.

A

tissue stop

36
Q

The ability of a removable partial denture to resist dislodging forces during function.

A

Retention

37
Q

A unit of a removable partial denture that engages an abutment tooth in such a manner as to resist displacement of the prosthesis away from basal seat tissues.

A

Direct retainer

38
Q

Resistance to gingival displacement
(occlusal rests).

A

Support

39
Q

During placement and removal of the partial denture the retentive arm flexes over the height of contour and generates energy. At this point the rigid reciprocal arm should contact the guiding plane and prevent orthodontic movement from taking place.

A

Reciprocity

40
Q

Resistance to lateral movement (reciprocal arms, minor connectors).

A

Stability

41
Q

Retentive arms located in undercuts on the abutments are for the function of?

A

Retention

42
Q

Encirclement of ___________ of the tooth prevents the prosthesis from moving away from the tooth.

A

greater than 180°

43
Q

At rest, a direct retainer should not exert force against a tooth.

A

Passivity

44
Q

4 clasps used in tooth borne (class iii, iv) cases?

A
  1. simple akers (circumferential)
  2. ring clasp
  3. double akers (embrassure)
  4. c-clasp
45
Q
  • The most simple and versatile clasp (clasp of choice in tooth-borne cases)
  • Clasp assembly has one retentive arm opposed by a reciprocal arm originating from the rest.
A

Simple akers (circumferential) clasp

46
Q

Begins above the height of contour, and curves and tapers to its terminal tip, in the gingival 1/3 of the tooth, well away from the gingiva.

A

Retentive arm

47
Q

Is in the middle 1/3 of the tooth, and is broader occluso- gingivally, does not taper and is either entirely above the height of contour or completely on a prepared guiding plane – it should never be designed into an undercut, as it is a rigid element.

A

Reciprocal / bracing arm

48
Q

Advantages:
- Excellent bracing qualities.
- Easy to design and construct.
- Less potential for food
accumulation below the clasp.

Disadvantages:
- More tooth coverage than bar clasps.
- More metal is displayed than with
bar or combination clasps.
- Adjustments are difficult or impossible due to the half round nature of the clasp.

A

Simple Akers

49
Q
  • Encircles nearly the entire abutment tooth.
  • Usually used with mesially and lingually
    tilted mandibular molars.
  • Should always be used with a supporting
    strut on the non-retentive side with an auxiliary occlusal rest on the opposite side.
A

Ring clasp

50
Q
  • Used in a quadrant where no edentulous area exists, or where a distal approach clasp cannot be used on the most.
  • Two rests, two retentive arms, and two bracing arms
  • Double rests with definite shoulders to
    prevent weakening of clasp arms,
    separation of teeth and food impaction.
A

Double Akers (embrassure) clasp

51
Q
  • The retentive area (undercut) is adjacent
    the occlusal rest.
  • The upper arm is a minor a connector
    giving rise to tapered lower arm.

Advantages:
- Allows use of undercut adjacent
to edentulous space.

Disadvantages:
- Almost impossible to adjust.
- Non-esthetic.
-Difficult to fabricate so the upper portion of the retentive arm clears the opposing occlusion.
- Covers extensive tooth surface
and acts as a food trap.
- Insufficient flexibility on short crowns due to insufficient clasp arm length.

A

C-Clasp / hair-pin / reverse action

52
Q

Stress releasing clasp assemblies include: (3)

A
  1. Bar clasp with mesial rest (RPI)
  2. RPA clasp
  3. Combination clasp
53
Q

This clasp assembly is similar to the RPI design except a circumferential clasp (Akers) is used instead of the I-bar.

This clasp arises from the proximal plate and terminates in the mesio-buccal undercut.

It is used when there is insufficient vestibule depth or when a severe tissue undercut exists.

A

RPA clasp

54
Q

Is similar to the cast circumferential clasp with the exception that the retentive arm is fabricated from a round wrought wire (platinum-gold- palladium alloy or chrome-cobalt alloy).

A

Combination clasp

55
Q

This rest could lead to distal tilting and possible loss of the abutment tooth.

A

Distal rest / disto-occlusal

56
Q

This axis passes through rests of the most posterior
abutment teeth and is called?

A

Fulcrum line

57
Q

Rotation of a partial denture about the fulcrum line is prevented by __________ placed against definite rest seats on the opposite side of the fulcrum line from the distal extension base.

A

indirect retainers

58
Q

Functions of this is to:

  • Support and retention of the denture teeth.
  • Transmission of stresses to oral tissues (maximal coverage within anatomic limitations,
    accurate reproduction of supporting tissues)
  • Improve esthetics.
A

Denture base & denture teeth

59
Q

The most common type of denture base used in RPD; they should be routinely used in distal
extension cases to allow for relining of the base to maintain mucosal support.

A

Acrylic resin base

60
Q

Can be used wherever acrylic resin bases are used. However, the esthetic result can be compromised unless the metal can be veneered with sufficient thickness of acrylic.

A

Metal base

Prostho 2 (RPD) (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions