Pontics

Question 1

What types of edentulous spaces are there?

Answer 1

Class I: Bucco lingual loss of tissue + normal ridge height

Class II: Loss of ridge height, normal ridge width

Class III: Combination of loss in height and width

Question 2

What is a method for ridge augmentation?

Answer 2

• Split thickness pedicle graft
• Increases height of ridge by grafting extra tissue, methods include:
• Removing tissue from lingual, opening up the ridge and suturing this into the ridge tip
• Opening up the ridge and grafting foreign tissue inside then resuturing the ridge tissue together that foreign tissue is completely covered
• As with second option but some foreign tissue showing externally

Question 3

What are the functions of pontics?

Answer 3

• Substitute tooth
• Restore appearance, comfort, function, occlusion, speech
• Satisfy biomechanical needs of healthy tissues, promote mechanical longevity

Question 4

What materials are available for pontics?

Answer 4

• Cast alloy
• Acrylic resin
• CR (sinfony)
• FRC (fibre reinforced)
• Porcelain

Question 5

What are the advantages, disadvantages, indications, contraindications of metal ceramic pontics?

Answer 5

Adv:

• Aesthetics
• Biocompatible

Dis:

• Difficult if abutment not metal ceramic
• Weaker than all metal

Indicated for most situations

Contraindicated long spans with high stress

Question 6

What are the advantages, disadvantages, indications, contraindications of all metal pontics?

Answer 6

Adv:

• Strength
• Straightforward

Dis:
Non aesthetic

Indications: mandibular molars, high stress

Contra: aesthetics important

Question 7

What are the advantages, disadvantages, indications, contraindications of FRC pontics?

Answer 7

• Adv:
• Conservative when used with inlay preps
• Aesthetics
• Ease of repair

Dis:

• Long term success unknown
• Limited to short span

Indications:
-High aesthetic concern

Contra: Long span FPD

Question 8

What are the types of pontics?

Answer 8

Sanitary

• Generally posterior
• Space between pontic and ridge
• Easy for cleaning
• Poor aesthetics

Saddle ridgelap

• Pontic sits exactly over ridge
• hard to keep clean
• Generally not recommended

Conical

• Pontics have a cone shape and thus contact ridge only at the tip
• Generally for molars with non aesthetic requirement
• Good access for cleaning but food trap still problem in undercut
• Poor aesthetics
• contraindicated in poor OH and high aesthetic need

Modified ridgelap

• Contacts ridge on labial but stays clear of ridge on lingual
• Used for highly aesthetic situations
• Easy to clean
• Some food packing

Ovate

• Surgically modify alveolar ridge to resemble col shape (create concave shape for pontic to sit on)
• Primarily for upper anteriors
• Excellent aesthetics
• Minimal food entrapment + easy to clean
• Requires some surgical prep (so contra in pts who do not want minor surgery)

Question 9

What are the issues with cleaning ridgelap, modified ridge lap, ovate?

Answer 9

• Ridge lap: dental floss can not contact pontic tissue surface in concavity
• Modified ridge lap: dental floss can contact more of tissue but concave area in centre of tissue contacting surface can not be cleansed
• Ovate: dental floss can be brought into intimate contact with most tissue contacting surface

Question 10

T/F lingual/palatal embrasures are more opened (deeper/more pronounced) than buccal/labial embrasures?

Answer 10

T

Question 11

How can loading be reduced on distal cantilever pontics?

Answer 11

-REduce the size

Question 12

What are soldered connectors? When are they used? What is the limitation?

Answer 12

• When pontic is joined via soldering to retainers, rather than being a single piece of metal
• Used to correct fit of one-piece casting and simplify complex bridge construction
• Solder joint is weakest link in bridge