Posterior Crown Preparations Flashcards
What are the functions of posterior crowns?
Maintenance of existing tooth structure, maintenance of occlusion, mastication, and aesthetics
What are posterior all ceramic crowns made of?
Amber Mill
What preparation is required for posterior all ceramic crowns?
Minimal preparation required
What is Amber Mill?
Lithium disilicate milled blocks
What are the properties of Amber Mill?
Relatively strong, digital milling high fit accuracy, good longevity durable, bio-inert, good aesthetics, and can be used anteriorly
What is the section of Amber Mill at margins?
Thin 0.3-1mm section
What is the definition of milled?
Reduced to fine particles by grinding in a mill
What are the new all ceramic crowns at dental hospital?
Table tip, thin veneer, veneer, anterior crown, inlays, onlays, partial crown, and posterior crown
What are posterior metal ceramic crowns made of?
Co Cr base layer with ceramic overlay (previous presentation) cast/digitally printed
What are the properties of Co Cr base layer with ceramic overlay?
Relatively strong, good longevity durable, bio-inert, and good aesthetics
What preparation is required for posterior metal ceramic crowns in functional cusp area?
Heavier preparation required 2mm
What is the functional cusp in maxillary arch?
Palatal cusp
What is the functional cusp in the mandibular arch?
Buccal cusp
What are the old style posterior metal ceramic crowns?
Porcelain fused to metal crowns
What are the modern posterior metal ceramic crowns?
All porcelain crowns
What did full veneer metal crowns used to be known as?
Full gold crowns
What was originally used in full venner metal crowns?
Type III gold alloy (75% gold Au) expensive
What is a benefit of using type III gold alloy (75% gold Au)?
Softer malleable deformed in thin sections
What are the properties of type III gold alloy (75% gold Au) full veneer metal crowns?
Strong, well fitting, good longevity durable, bio inert, and poor aesthetics
What is the section of type III gold alloy (75% gold Au) at margins?
Thin 0.3mm section
What alternative alloys are used in full veneer metal crowns?
White gold and non-precious alloys
What are the constituents of white gold?
Au – 30%, Pd – 10-35%, Ag – 35-60%
What are the disadvantages of white gold?
More difficult to cast and corrosion
What are the constituents of non-precious alloys?
Nickel-Chromium, Chrome-Cobalt, & Titanium