dental materials ch 43 Flashcards
restorative
ability to replace or bring something back to its natural appearance and function. (chipped tooth)
esthetic
restoring to an artistically pleasing appearance
infection control
not to cross-contaminate, use over gloves, tissues, paper towel, cotton pliers, etc.. when handling containers/materials
biting forces
average biting/chewing with natural dentition= 130-170 lbs molar, 40lbs incisors.
Around 28,000 lbs of pressure per square inch on a single cusp of a molar
tensile stress
pulls and stretches the material
compressive stress
pushes the material together
shear stress
the breakdown of the material as a result of something sliding over the two areas
the measure of the capacity of a metal to be stretched or drawn by a tensile force without fracture
ductility
the measure of the capacity of a metal to be extended in all directions by a compressive force
malleability
thermal change
causes contraction and expansion, need to protect the pulp from thermal shock
microleakage
space between tooth structure and the restoration in which fluid debris and microorganisms could enter
how is an electrical current or galvanic action created
when two different metals are present in the oral cavity
corrosive properties
reaction within a metal when it comes into contact with corrosive factors (temp, humidity, saline)
most corrosion is
only surface discoloration (tarnish)
solubility
a substance dissolving in another substance
flow
a product going inside the tooth and how it flows inside
adhesion
to bond or attach two items together
what affects adhesion
wetting, viscosity, surface characteristics, and film thickness
wetting
the ability of a liquid to flow over the surface & into small irregularities
viscosity
property of a liquid that causes it not to flow easily
t/f; a liquid flows more easily on a rough surface than on a very smooth surface and will influence the wetting ability
true
film thickness
the thinner the film the stronger the adhesive junction
retention
ability to hold two things firmly together when they will not adhere to each other naturally
curing
setting material into a hardened, permanent state
auto-cured material
hardens as a result of a chemical reaction of the materials being mixed together.
must be mixed and placed when you need to use it
light-cured material
does not harden, until it has been exposed to a curing light.
how does an auto-cured material harden or set
by chemical reaction
what is used to triturate capsulated dental materials
amalgamator
