Pontics Flashcards
What types of edentulous spaces are there?
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
What is a method for ridge augmentation?
- 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
What are the functions of pontics?
- Substitute tooth
- Restore appearance, comfort, function, occlusion, speech
- Satisfy biomechanical needs of healthy tissues, promote mechanical longevity
What materials are available for pontics?
- Cast alloy
- Acrylic resin
- CR (sinfony)
- FRC (fibre reinforced)
- Porcelain
What are the advantages, disadvantages, indications, contraindications of metal ceramic pontics?
Adv:
- Aesthetics
- Biocompatible
Dis:
- Difficult if abutment not metal ceramic
- Weaker than all metal
Indicated for most situations
Contraindicated long spans with high stress
What are the advantages, disadvantages, indications, contraindications of all metal pontics?
Adv:
- Strength
- Straightforward
Dis:
Non aesthetic
Indications: mandibular molars, high stress
Contra: aesthetics important
What are the advantages, disadvantages, indications, contraindications of FRC pontics?
- 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
What are the types of pontics?
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)
What are the issues with cleaning ridgelap, modified ridge lap, ovate?
- 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
T/F lingual/palatal embrasures are more opened (deeper/more pronounced) than buccal/labial embrasures?
T
How can loading be reduced on distal cantilever pontics?
-REduce the size
What are soldered connectors? When are they used? What is the limitation?
- 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
