RPD 04 - Components Part 2 (Quiz 2)

Indirect retainers

Define the following:

Framework components that assist the direct retainers in preventing displacement of distal extension denture base away from the supporting tissues by resisting lever action from the opposite side of the fulcrum line

fulcrum line

Define the following:

An imaginary line that crosses the most distal rests of a retainer

greater

the further away an indirect retainer is from the fulcrum line, the _______ the retention

indirect retainers

All of the following are factors influencing the effectiveness of _______:

- Distance from the fulcrum line

- Perpendicular to and as far from the fulcrum line

- Rigidity of the connector

- Supporting tooth structure

- No tooth incline/weak tooth

- Accurate and definite contact with properly designed horizontally oriented rest seats

Indirect retainers

What should be perpendicular to and as far from the fulcrum line as possible?

retention

Indirect retainers participate in stability, retention AND support. But what is the PRIMARY function?

- Aid in stabilization

- Support major connector

- Facilitating stress distribution

- Indicator for relining

What are the auxiliary functions of a indirect retainer?

Major connectors

What has the following characteristics:

- Connect all parts of the partial denture together

- Must be rigid to transmit force equally to all areas and structures

- Must be properly located in relation to gingiva and movable tissue

- Must not impinge on gingiva

Support

What is the MAIN function of a maxillary major connector?

maxillary major connectors

What has the following characteristics:

- Usually a plate that touches the tissue

- No relief

- Provides support

Maxillary major connector

What has the following characteristics:

- 6 mm from the gingival margins

- Parallel to the gingival margin

- 90 degrees to palatal midline

- Not extend onto the soft palate

6mm

maxillary major connectors borders must be ___mm from the gingival margin

parallel

maxillary major connectors borders must be __________ to the gingival margin

90°

maxillary major connectors borders must be _____ degrees to the palatal midline

soft palate

maxillary major connectors borders must not extend onto the ________

rugae (run through valleys to reduce the sensation of foreign object)

when fabricating a maxillary major connector, you should open the ______ area to allow for better speech

beading

What accommodations are being made for this maxillary major connector:

0.5mm

when fabricating a maxillary major connector, beading anteriorly and posteriorly for better tissue contact to prevent food entrapment should be ___mm deep with a rounded channel

6mm

when fabricating a maxillary major connector, the material should fade away within ___mm from the gingival margin of the remaining teeth

irritation/inflammation

when fabricating a maxillary major connector, the channel depth should be reduced in areas of thin tissue coverage such as mid- palatine raphe or a palatal torus to prevent ________

Palatal torus or a prominent median suture line

Relief should NOT be used under the maxillary major connector, except in the presence of what?

Kennedy Class III with short edentulous span

When fabricating a maxillary major connector, palatal straps are most common for which Kennedy Class?

8-15mm

when fabricating a maxillary major connector, the width of a palatal strap must be between ____-____mm for good support and rigidity

palatal strap

ID the type of maxillary major connector:

- Good support and rigidity

- Most comfortable

Palatal plate/extended strap

ID the type of maxillary major connector:

palatal plate/extended strap

This type of maxillary major connector is:

- For any classification when edentulous support needed (keep rugae open when possible)

- Periodontally compromised remaining teeth

- Patient has no interfering torus

- Enhances thermal conductivity

anterior palatal strap/Horseshoe

ID the type of maxillary major connector:

anterior palatal strap/Horseshoe

this type of maxillary major connector is least desirable due to poor support and rigidity:

anterior palatal strap/Horseshoe

This type of maxillary major connector is:

- Least desirable due to poor support and rigidity

- May be used for Kennedy Class IV or III w/ anterior modification

- Good for patient with palatal tori

antero-posterior palatal strap

ID the type of maxillary major connector:

antero-posterior palatal strap

This type of maxillary major connector is:

- Used for any classification with strong abutment teeth and excellent residual support

- Good support, excellent rigidity

- Maybe not acceptable by patient due to the multiple borders

- Both straps should be at least 8mm in width

8

when fabricating a antero-posterior palatal strap, the width of both anterior and posterior straps must be at least ___mm for good support and rigidity

complete palatal plate

ID the type of maxillary major connector:

complete palatal plate

This type of maxillary major connector is:

- With poor abutment support, poor ridge conformation, and weak periodontal support, palatal support becomes very important

- Patients do NOT have interferring tori

- Location and size of edentulous area

- Amount of support available

- Patient preference

- Future tooth loss

- Fulcrum line

What are the 5 selection criteria for selecting a maxillary major connector?

half pear shaped

What is the shape of a Lingual Bar mandibular major connector?

5mm

A lingual bar should have a height of ___ mm

2mm

A lingual bar should have a thickness of ___ mm

3mm

The superior border of a Lingual Bar should sit ___mm away from the gingival margin

8mm

In order for a patient to receive a lingual bar, they must have a functional depth of at least ___mm of lingual vestibule

lingual bar

ID the type of mandibular major connector:

lingual bar

ID the type of mandibular major connector:

- Half pear shaped: 5 mm high, 2mm thick

- Superior border: 3mm from the gingival margin

- At least 8 mm of functional depth of lingual vestibule (vertical space between gingival margins of teeth and floor of mouth)

- Most comfortable

lingual bar

What is the most common and most comfortable type of mandibular major connector?

lingual bar

What mandibular major connector is contraindicated for patients with mandibular tori?

Lingual border molding to fit bar into the lingual sulcus like a denture border

When fabricating a mandibular lingual bar major connector, the final impression should include...

Blocking salivary ducts

When designing a mandibular lingual bar, care must be taken to avoid what?

lingual bar OR lingual plate (Linguoplate)

A patient that needs a mandibular denture and has 8mm of space between the gingival margin of the anterior teeth and the lingual sulcus. What is the patient eligible for?

lingual plate (linguoplate)

A patient that needs a mandibular denture and has less than 7mm of space between the gingival margin of the anterior teeth and the lingual sulcus. What is the patient eligible for?

lingual plate (linguoplate)

ID the type of mandibular major connector:

lingual plate (linguoplate)

ID the type of mandibular major connector:

- Used for patients with less than 7mm lingual vestibule

- Contacts teeth just above cingulum rests at each end

- Scalloped appearance for patients with close interproximal spaces

- Good for patients with weak periodontal support requiring splinting

- Good for patients with mandibular tori

- Patients with future loss of teeth

- Steps back for diastemas

- Can interfere with speech

Double lingual bar (Kennedy bar or Split bar)

ID the type of mandibular major connector:

Double lingual bar (Kennedy bar or Split bar)

ID the type of mandibular major connector:

- Similar to lingual plate except for large open space between two bars

- 2-3mm in height (incisogingival)

- About 0.6-1mm thick (faciolingual)

- Rests at each end

- Risk of food trapping, especially in crowded dentition

- Can cause tongue irritation

- Interferes with speech

- Indicated when open embrasures exist

2-3mm

the height of the most superficial bar of a Double lingual bar (Kennedy bar or Split bar) is between ___-___ mm inciso-gingivally

0.6-1mm

the width of the most superficial bar of a double lingual bar (Kennedy bar or Split bar) is between ___-___mm faciolingually

labial bar

ID the type of mandibular major connector:

labial bar

ID the type of mandibular major connector:

- Patients with severely lingually inclined teeth

- Used for patients with VERY large tori

swing lock

ID the type of mandibular major connector:

swing lock

ID the type of mandibular major connector:

Used for patients with:

- Unfavorable tooth contour

- Unfavorable soft tissue contour-tori

- Teeth with questionable prognosis

swing lock

Which mandibular major connector has a gate, latch and hinge?

- Location of edentulous area

- Functional depth of lingual vestibule

- Anticipated loss of natural teeth

- Inclination of remaining teeth

What are the 4 selection criteria for selecting a mandibular major connector?

minor connectors

These connect parts of the partial denture to the major connector such as:

- Indirect retainers or auxiliary rests

- Clasp assemblies (rests, retentive arms, bracing arms)

- Mesh that retains denture base, esthetic and occlusal components

stability

IMPORTANT: What is the primary function of minor connectors?

Minor connectors

What has the following characteristics:

- Acts as a stability element

- Transfers functional stress to abutment teeth

- Must be rigid

- Crosses gingival margin at right angle

- Junction to major connector is slightly curved

5mm

IMPORTANT: Minor connectors positioned in embrasure spaces should have at least ___mm between two minor connectors

3mm

There should be ___mm space between the gingival margin and the mandibular minor connector

open lattice or ladder like design

ID the design of denture base minor connector:

mesh design

ID the design of denture base minor connector:

loop design

ID the design of denture base minor connector:

beads

ID the design of denture base minor connector:

retentive posts

ID the design of denture base minor connector:

mesh and loop

Which design for the denture base minor connectors have very good retention?

As far posteriorly as is practical

In a maxillary RPD, where should the denture base minor connector extend to?

2/3 the length of the residual ridge

In a mandibular RPD, where should the denture base minor connector extend to?

minor connector

Are tissue stops considered a major or minor connector?

tissue stops

What part of the minor connectors stabilize the framework during resin packing and processing; indicator for the fit, contact the oral mucosa?

tissue stops

ID what the arrows are pointing at:

1mm

on the buccal side, the denture base minor connector extension should be about ___mm over the residual ridge crest

2mm

the lingual side, the denture base minor connector extension should be about ___mm short of the denture border in the lingual aspect

finish line

What has the following characteristics:

- < 90° butt joint (internal angle) between major connector and minor connector for mechanical retention

- Smooth transition between denture base metal and acrylic

2mm

The external finish line for the maxilla, should be _____mm palatal to the palatal surfaces of adjacent teeth

Guide plate

The external finish line for the mandible, should be continuous from the _________

Palatal

when establishing the internal finish line for the maxilla, it should be slightly more ______ to the external finish line

mesial

when establishing the internal finish line for the mandible, it should be______ to the external finish line

maxilla's external finish line

The left arrow denotes the location of what finish line?

mandible's external finish line

The arrow denotes the location of what finish line?

maxilla's internal finish line

The purple line in the picture denotes the location of what finish line?

maxilla's external finish line

The blue line in the picture denotes the location of what finish line?

mechanical retention

What is the purpose of finish lines?

snowshoe principle (distribution of forces to as large as an area as possible)

Define the following:

The broader coverage of the denture base, the more support with the least load per unit area (more forces distributed per surface area)

Denture bases

What has the following functions:

- Support the artificial teeth

- Transfer the functional forces to supporting tissues

- Functional stability and comfort

- Snowshoe principle

- Cosmetic effect of the replacement

- Stimulation of underlying tissue the residual ridge

- Secondary retention via intimate contact with the underlying tissue

support

What is the PRIMARY function of denture bases?

resin denture base

ID denture base type:

- Restoration of anatomic contour, occlusion, and esthetics

- Anticipated need to reline or adjust the base

- Variety of shades

- Poly-methyl-methacrylate (PMMA)

metal denture base

ID the denture base type:

- Short-span tooth supported

- Limited vertical height

- Cast metal pontic

- Maximum strength

- Better tissue adaptation

- More accurate form

- Enhanced thermal conductivity

- Less bulk

- Inability to relining or rebase poorly fitting areas

metal denture base

What kind of denture base should be used for well healed and ideally contoured residual ridges?

- Acrylic resin (mostly use this)

- Porcelain teeth

- Reinforced acrylic pontics

What are the options for replacement of anterior teeth on a RPD ? (3)

- Acrylic resin

- Composite resin

- Porcelain teeth

- Metal pontics

- Tube tooth

What are the options for replacement of posterior teeth on a RPD ? (5)