Pontic Design, Index, Connectors, Etc Flashcards
When would post porcelain soldering be indicated on a PFM FPD?
If teeth have moved between final impression and restoration
What is an advantage of pre-porcelain soldering of PFM FPD?
Allows diagonal cut across a full pontic to have greater surface area than interproximal cut. Done when a cast FPD had to be made in 2 pieces
How do you index a FPD with duralay?
Cut gap b/w retainer and pontic, place duralay on top, invest, heat and flow solder in, must account for metal expansion
Which is the strongest type of rigid connector: pre-porcelain vs post-porcelain?
Pre-porcelain is stronger than the post porcelain connector
What is the strongest type of rigid connector: cast vs soldered?
Cast Connector is stronger than the soldered connectors
Which nonrigid connector is used when abutment teeth have disparate long axis, so they are prepared respective to their long axis, then the wing is made parallel to the long axis of the most mesial prep. The pontic is designed to accommodate the wing, and the pontic is attached to the mesial abutment?
Cross pin and Wing
Which nonrigid connector is placed entirely in the pontic and is useful on tilted abutments where the dovetail prep would mean very drastic box prep in the abutment. In layman’s term one half of the pontic ( e.g. the bottom half) is attached to a crown, while the other half of the pontic (e.g. the top half)is attached to another crown. When the individual crowns are placed, their extensions form the entire pontic. The two pieces of pontic are not cemented together
Split pontic
What is the term for when there is a key in pontic with Keyway in retainer as a nonrigid connector best suited for relieving stress at midspan on long pointics or to align distal path of insertion on tilted abutment. The Key and keyway are not cemented together
Dovetail
What are 2 types of pontic connectors?
- Rigid (solder or cast connectors)
2. Non rigid (precision or stress breakers)
What is the most common edentulous ridge classification?
Class III
What is the classification for a normal ridge with minimal deformity?
Class N
What is the ridge classification with loss of both ridge width and height?
Class III
What is the ridge classification with loss of ridge height with normal width?
Class II
What is the ridge classification with loss of faciolingual ridge width, with normal apicocoronal height?
Class I
Can the pontic extend past the mucogingival junction?
No, doing so would create an ulcer
What is the only tissue a pontic should contact?
Keratinized
Should the pontic be narrower or wider than natural tooth?
Slightly narrower
Should resin pontic be used near tissue?
No because resin is porous
What are 3 pontic materials?
- Metal ceramic
- Cast metal
- Resin processed to metal
What pontic has a round end design where esthetics are a concern. Tissue contacting edges is bluntly rounded and is set into a concavity on the ridge. Works well with a broad flat ridge?
Ovate
What is a pontic with a rounded tip that is small in relation to the overall pontic size and is indicated on a thin mandibular ridge in nonappearance zones?
Conical
What is a pontic that has no contact with edentulous ridge. Used in nonappearance zones. Can be all metal, and the occlusal gingival thickness should be no less than 3.0mm?
Hygienic
What is a pontic that possesses all convex surfaces, that does contact the ridge, but is cleansable. Most common pontic design in the appearance zone?
Modified ridge lap
What is a pontic that looks most like a tooth, but obliterates the facial, lingual and proximal embrasures, and is hard to clean and causes tissue inflammation. Should not be used.
Saddle/Ridge lap
