Exam 3: Bonding to Enamel Flashcards
adhesion requirements
- clean adherend (substrate)
- good wetting
- intimate adaptation
- bonding
- good curing
requirement for a clean adherend
The substrate must not contain anything on the surface
that would prevent an adhesive from coming into good contact with it.
requirement for good wetting
The adhesive must spread onto the adherend with a low contact angle
so that it wets the surface and develops good intimate contact.
requirement for intimate adaptation
If good wetting occurs and the material flows adequately, then it
can penetrate into all the surface interstices and develop good adaptation
requirement for bonding
The adhesive should interact in as many ways as possible with the substrate.
requirement for good curing
The entire process depends on the adhesive (and restorative filling
materials) becoming fully cured
performance factors; what accounts for 50%+ observed variability?
- operator
- design
- materials
- intraoral location
- patient
operator (dentist)
in bonding to enamel, which bonding mechanism is most important?
micromechanical mechanism
in bonding to dentin, which bonding mechanism is most important?
all used in combination, micromechanical and hybridization are most relevant
______ and ______ can be used to
chemically bond to enamel.
Glass ionomer cements (GICs) and Resin-modified glass-ionomers (RMGICs)
in GIC and RMGICs, (+) charges in enamel (from ___ions) strongly interact with (-) charges in the dental material (______) in the GICs and RMGICs.
Ca, (from the carboxylic groups (-COO-)
what is buonocore?
formed in the 1950s that suggested etching enamel prior to the material application,
Between 1960-70s, optimum bonding conditions with ______ has been established,
and this technique is known as ________ or ______ technique
phosphoric acid, etch-and-rinse or the total etch
optimum bonding steps (4)
- etching
- etchant washed/rinsed away
- enamel surface dried
- apply adhesive
When the H3PO4 etches enamel, it reacts with the mineral and _______, which results in a ______, mostly the ____ etch pattern
dissolves it heterogeneously, rough etched enamel surface, Type I
long-term durability of bonding between
the material and enamel depends on…
- etching effectiveness
- strong interaction between etched enamel and material
- the intrinsic mechanical properties of the dental material and enamel
do you need rinsing in a self-etch system?
no
Orthodontic bands can be alternatively bonded to etched enamel with ___________
dimethacrylate-based resin adhesives or glass ionomer cements.
sealants are the ______ dimethacrylate-based resin composites
most flowable
The standard application of sealants is after enamel etching with _______ agent. They
are _____ materials
phosphoric acid, light cured
The acidic monomer used in self-etched systems normally bear _________,
in an attempt to produce etching effects
carboxylic or phosphoric acid groups
The smear layer is ________ with self-etch adhesive system
partially dissolved but not removed
The pH in self-etch systems is between ___________ than phosphoric acid based etchants
10 and 1000 times less acidic
