Flashcards in framework and pontic design Deck (18):
what thickness is needed to avoid fracture on ceramic veneer? whats the min. for esthetic reasons?
at what rate does enamel ware?
10 micrometers a year
why is it a good idea to have metal on the lingual surface of maxillary incicors?
it wears less than ceramic against the natural teeth.
what should you keep in mind while restoring opposing teeth?
contacting surfaces must be the same material, like ceramic opposing ceramic.
what must you analyze before placing a pontic?
mesiodistal width, occlusocervical width, buccolingual width, and edentulous ridge area.
what are biological considerations for successful pontic design
easy to clease, can access abutment teeth easily, no pressure on ridge
what are esthetic considerations for successful pontic design?
shape of a tooth, appears to "grow" out of edentulous ridge, sufficient space for porcelain
what are mechanical considerations fo successful pontic design?
rigid, strong connectors, metal ceramic framewor( to resist fracture)
residual ridge ideal
smooth regular surface of attached gingiva, good height and width, no freenum attachment
what would a loos in residual ridge result in?
open gingival embrasures and food compaction.
pontic designs are classified into 2 general groups....
those that contact the oral mucosa and those that dont.
selection mainly depends on ...
esthetics and oral hygiene.
Anterior: pontic adapted to tissue, emerging from gingiva.
Posterior: less esthetic but amenable to oral hygiene.
name the 5 pontics
Saddle/Ridge Lap pontic
Modified Ridge Lap pontic
advantages and disadvantages of sanitary/hygienic pontic
A: easy cleaning
D: entrapment of food, may lead to tongue habits
advantages and disadvantages of saddle/ridge lap ponitc
A: concave shape that overlaps ridge simulating emergence
D: not accessible to clean which leads to plaque and tissue inflammation.
advantages and disadvantages of modified ridge lap pontic
A:combines best features of saddle and hygenic pontics, good esthetics and easy cleaning, overlaps ridge on facial side but not on lingual,( gingival surface must have no depressions), Most common pontic for visible teeth.
advantages and disadvantages for conical pontic
AKA: egg, bullet, or heart shaped
A: easy cleaning,
Should be as convex as possible with only one contact at center of ridge, Most commonly used in mandibular incicors where esthetics is less important.