Brainscape's Knowledge GenomeTM

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


See full index

Fixed 2- Summer 2015 > Fixed Partial Dentures and Pontic Design > Flashcards

Fixed Partial Dentures and Pontic Design Flashcards

1
Q

Which component of the Fixed Partial Denture will fit onto the abutments?

A

the retainers

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

Which component of the Fixed Partial Denture will fit over the edentulous area?

A

the pontic

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

How does the pontic attach to the retainers?

A

through the “connectors”

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

What are two major contraindications to an FPD?

A
  1. Excessive edentulous span

2. Weak abutment teeth

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

Ante’s Law states that the peri-cemental area of the abutment teeth must be _______ the peri-cemental area of the pontic.

A

greater than or equal to

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

What is the effect of length (edentulous area) on deflection of the FPD?

A

Deflection = length cubed
2x length = 8x deflection
3x length = 27x deflection

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

What is the effect of “connector thickness/height” on deflection of the FPD?

A

Increased connector thickness/height results in decreased deflection. D= (1/H)^3
example: 1/2 thickness = 8x deflection

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

What is the danger of having three pontics between two abutments?

A

with heavy occlusal loads the metal will flex and the porcelain will chip

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

What are three considerations for abutment selection?

A
  1. Clinical crown-to-root ratio
  2. Root form
  3. Tooth angulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the MINIMUM amount of bone (crown-to-root ratio) that is acceptable as an abutment?

A

1:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the IDEAL crown-to-root ratio (amount of bone) that is acceptable as an abutment?

A

2:3

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

True or False: If the clinical crown-to-root ratio is greater than one, the FPD will fail.

A

True, minimum required bone is a ratio of 1:1

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

When selecting abutments, what is the importance of “root surface area?”

A

Root surface area = periodontal support

*Certain teeth have a better cross-sectional configuration for support of the partial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which teeth have a root surface area (cross-sectional configuration) that is NOT well suited for use as abutments?

A

Lateral incisors (uniform and ovoid shape)

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

The root design for abutment teeth will influence stability of the partial. Which is stronger: curved or straight roots?

A

Curved

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

The root design for abutment teeth will influence stability of the partial. Which is stronger: convergent or divergent roots?

A

Divergent

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

Why are “curved” and “divergent” roots preferred over “straight” and “convergent” roots for abutment teeth?

A

Curved/Divergent provides greater root surface area

Root Surface Area = Periodontal Support

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

What happens if the connector size is sacrificed for esthetics?

A

The connector will break

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

What are the boundaries within which esthetics may be considered more than strength?

A

Anterior…or where ever the client thinks it is important

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

Why must you check the tooth preparations from all different angles?

A

Because there may be an undercut within one prep, between the two preps, or both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are three options for preparing abutment teeth that have different long axes?

A
  1. Reposition teeth prior to FPD: orthodontics
  2. Use intracoronal attachments
  3. Conservative removal of offending proximal contacts
22
Q

What are precision attachments? Common type?

A

-Fixed attachments that provide retention and/or support in the case that abutments are not parallel; therefore, there is a contraindication for FPD
Key-Way attachments: “female and male parts” that connect together

23
Q

If removal of proximal contact is necessary when preparing abutment teeth (due to different long axes), what must be considered for the proximal teeth?

A

PULP HORNS: careful, patient’s age?

24
Q

What are the three general considerations when evaluating the edentulous area for a pontic?

A
  1. Mesio-distal width
  2. Occlusocervical distance
  3. Bucco-lingual diameter of remaining alveolar ridge
25
Q

_____ _____ _____ has most likely occurred in the edentulous area if a tooth were extracted several years prior.

A

Buccal Plate Resorption

26
Q

Why would buccal plate resorption cause an issue for the FPD?

A

The ridge thickness B-L would most likely be uneven and would cause the pontic to lean toward the recessed area.

27
Q

If vast amounts of resorption occurred, an edentulous ridge can be prepared for the FPD by use of a ______.

A

Graft

28
Q

If cervical lines are uneven (ex. one tooth appears pushed in), how can the arch be restored to a more even contour?

A

Orthodontics (erupt that tooth)

29
Q

Why would you use orthodontics prior to extracting a tooth?

A

Ortho can be utilized in order to erupt teeth and pull BONE down prior to extractions. This will prevent serious resorption of the edentulous area.

30
Q

What are the six common pontic forms?

A
  1. Ridge Lap (saddle)
  2. Modified Ridge Lap
  3. Hygienic (sanitary)
  4. Modified hygienic
  5. Bullet
  6. Ovate
31
Q

What is a “ridge lap” pontic used for? Why is it not recommended?

A
  • Eshthetics*
  • emulates the contours and emergence profile of the missing tooth
  • Difficult to clean*
  • mucosal surface follows the contours of the gingiva
  • formation of ulcers
32
Q

What is a hygienic pontic used for? What is its disadvantage? Advantage?

A

Use: Mandibular posterior teeth
Disadvantage: No indication for maxillary teeth (shelf)
Advantage: Easy plaque control

33
Q

The distance between the pontic mucosal surface and gingiva should be _____ mm.

A

1-2 (definitely not less than 1 mm, 1.5 mm is ideal)

34
Q

What would happen if the hygienic pontic was not 1-2 mm from the gingiva?

A

It would be too difficult to clean under, the mucosa would become severely inflamed.

35
Q

What is the difference between a “modified hygienic” and “hygienic” pontic?

A

Modified = wider connectors = stronger, less esthetic

36
Q

What is a “modified ridge lap” pontic design?

A

MOST COMMON design

  • Hygienic from the lingual
  • Saddle from the buccal
37
Q

What are the benefits of the modified ridge lap design?

A

Esthetic

Cleansible

38
Q

True or False: The modified ridge-lap design should have a tight T-shaped tissue contact on the lingual.

A

FALSE. the T-shaped contact should be on the buccal (the side with the saddle, not the hygienic) and contact should be very minimal.

39
Q

Where is a “bullet” pontic design used?

A

Mandibular molars with knife-edge alveolar ridges

-if the ridge is wide…use a hygienic or food will get impacted

40
Q

Of the two mandibular molar pontic designs, which one is in contact with the mucosa?

A

“Bullet” Pontics (knife edge ridges)

41
Q

An ______ pontic will most likely be used if it is placed at the time of extraction. It provides good emergence profile but is hard to clean underneath.

A

Ovate

42
Q

When using an ovate pontic, what must be done extremely well?

A

the pontic MUST be highly POLISHED…risk for tissue damage or ulceration due to extension into the open socket

43
Q

The ovate pontic eliminates the potential for _______ ______ in the cervical portion of an anterior pontic.

A

Unsupported Porcelain

44
Q

Which two pontic designs have no contact or slight mucosal contact?

A 
Hygienic (none)
Modified Hygienic (slight)
45
Q

If using a cantilever pontic (one connector), where should the pontic be in regards to the abutment?

A

MESIAL

distal cantilever causes unfavorable load on abutment

46
Q

What is the best indication for a cantilever pontic? Why?

A

Missing lateral incisors

-the canine can be used as an abutment, leaving the central incisor un-prepared

47
Q

(Biological Consideration)
______-_______ contact between the pontic and underlying tissues is indicated to prevent ulceration and inflammation of soft tissue.

A

Pressure-free

48
Q

In the _____ region, a pontic should contact the gingival tissue.

A

anterior (appearance of emergence from soft tissue)

49
Q

(Biological Consideration)

To enhance hygiene, what must the patient be instructed to do?

A

Perform efficient plaque control and prevention

50
Q

What is a “pier abutment”?

A

Two edentulous ridges are separated by a tooth that can be prepped and made into an abutment (pier). Therefore, there are three abutment teeth and two ridges.
1110____0____0111

51
Q

What is the alternative to having a pier abutment? Why would this be chosen instead?

A
  1. Non-rigid connector (connects two separate pieces)
    -if common POW is too difficult to create
  2. Cantilever one of the pontics
    -prevents preparation of three teeth
    11111___0___0111
52
Q

The pontic design should be of ______ form for #20 and of _________ form for #4.

A

Hygienic #20 (mandibular)

Modified Ridge Lap #4 (maxillary)

Fixed 2- Summer 2015 (7 decks)

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