robbypowell's version from 2016-10-30 18:42

Lab session 1

Question Answer
Cement viscosity ______ (increases/decreases) as the particle size of filler increasesIncreases
T/F: Resin cements are essentially diluted contain less filler and are less viscousTrue
A greater proportion of resin in a resin cement makes for _____ (more/less) wear resistanceLess
Are conventional resin cements chemically bonding?No
_____ _____ implies a resin cement is capable of initiation by visible light-curing as well as by a self-curing reaction.Dual Cure
________ are so thin and translucent, light loss through material is minimal, and only the light-curable portion of a dual-cured resin cement is used.Veneers
The more _______ the indirect restoration is, the greater is the indication for dual-cured resin cementsopaque
The ________ the overlying restoration, the greater is the need for a dual-cured resin cement because of lack of light to drive photoinitationthicker
What type of "cement" is Rely-X?RESIN MODIFIED GLASS IONOMER luting cement
The commercial products Nexus, Variolink, and RELY•X ULTIMATE Adhesive Resin Cement are all ____ ______ resin cementsDual-cured
Power-liquid GI cements have a _____ bond strength to ceramic, but paste-paste GI has a ______ bond strength to ceramicLow; High
What is the reaction of conventional Glass Ionomer cements? (powder-liquid)GLASS attacked by the liquid acid, causing release of metal ions (calcium and aluminum), as well as fluoride. The metal ions now in solution react with the acid groups of the long chain polyacrylic acids, and form cross-links and build strength.
In an RMGI reaction and setting... which reaction happens first.... the GI or the Resin reaction?Resin reaction (providing early strength and resistance to water exchange.)
State what structures glass ionomers need in order to form chemical bonding to a substratePOSITIVE METAL IONS (cations) such as calcium in teeth and aluminum in ceramics or other metals.)
4 advantages of using a resin modified glass ionomer as a dental cementearly strength, early curing of margins, fluoride release, can bond other resins
These cements are typically called “universal,” because they can be used in almost any clinical situationSelf-adhesive cements
T/F: self-adhesive cements bond chemicallyTrue
Self-adhesive cements _______ (are/are not) associated with increased sensitvity? why?Are not; because smear layer is not removed
T/F: self-adhesive cements are good for porcelain veneers, zirconia and goldFalse (not good at any of these)
T/F: self-adhesive cements should not be used with porcelain veneers, zirconia indirect restorations, or goldTrue (cant bond chemically)
Effects of sandblasting metal are that it roughens the surface and increases the surface ______ and surface "energy". It is also has enhanced _______ , allowing resin to more easily flow along the surfaceArea; Wetting
is sandblasting alone is sufficient in providing adequate, long-term retention of a resin cement to metal surface?No
State the amount of silica present in the surface of metal alloys used for indirect restorations.Virtually NONE
State how a metal surface must be treated in order for a silane coupling agent to adhere to it. ______ needs to be addedSilane
State why noble metal surfaces are difficult for resin cements to bond to. _______ do not form at room temperature on noble metals.Oxides
State a simple method that can be performed to metal surfaces (without silica deposition) to render them more retentive to resin cements and the mechanisms for this retention. SULFUR-AND PHOSPHATE CONTAINING METHACRYLATES painted on to surface
State what components are found naturally in a ceramic to which a resin-based dental cement can bond.None
Does air abrasion of ceramics create micro-undercuts?No
Is zirconia acid-etchable?No
Acid is added to dental porcelain because acid removes _______ which then exposes the large particles of leucite (a crystalline component in some ceramics) and then corrodes them as well. This process leaves relatively large voids (lots of places for undercuts).Glass
t/f: all ceramics are etchableFalse
t/f: not all ceramics are etchableTrue
State the mechanism whereby a silane coupling agent attaches to bonding resin....covalently w 2 reactive sites (Si-O-Si bonds form on the end with glassy types of surfaces & carbon double bonds form with methacrylate C=C)
State why it is preferred to use warm air to dry the silane prior to placing on cementApplication of warm air speeds evaporation of water and ethanol from the silane, increasing bond strength to the ceramic by providing more bound Si-O units to the glass))

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