Module 1 Flashcards
Metal has atoms arranged in ______ or ________ arrangements?
regular
crystalline
Metal has a _____ thermal and electrical conductivity?
high
What 3 materials make up Porcelain/Ceramic?
Kaolin
Feldspar
Quartz
Porcelain is very ______ until it is _______
brittle
bonded
Porcelain has a _______ thermal and electrical conductivity?
low
Ceramic is termed ______ to mean it is not chemically reactive?
inert
A _______ ______ polymer is molded without chemical reaction?
thermoplastic
(molded by thermal means)
ex: mouthguard material
Thermosetting is a _____ change that takes place during _______?
chemical
molding
Thermoplastic polymers change due to _______ not _______ _______?
temperature
chemical reaction
Polymers are made up of?
monomers
Monomers are small ______ molecules that can be bound to _____ monomers to form a polymer?
organic
similar
Plastic is a type of ______ polymer?
synthetic
Rubber is a type of _______ polymer?
natural
What is the term for the conversion of monomers to polymers?
polymerization
What is a Copolymer?
two different monomers put together
What is the term for a network of adjacent polymer chains which make a polymer stronger?
Cross-Linking agent
________ is a type of dimethacrylic acid polymer?
Composite
Composite restorations are ______ filled?
heavily
What is the term for a coupling of two dissimilar metals?
galvanic response
The rate at which heat flows through a material is termed _______ ________
thermal conductivity
The ability to dissolve in a liquid is termed?
solubility
The liquid in which a substance dissolves is called the _____
solvent
The uptake of fluids into a solid is termed?
Absorption
Absorption can cause restorations or cements to?
deteriorate
What is the most common type of molecular response?
Secondary
A secondary molecular response is one that has no _______ union but unites by?
chemical
physical forces
The primary molecular response takes place due to chemical bonds that are based on _______ ______
polyacrylic acid
ie: glass ionomer
The ______ _______ is how well a liquid covers the surface of a solid?
wetting angle
A good adhesive has a wetting angle that approaches?
zero
We want ______ or a low wetting angle?
hydrophillic
A high wetting angle is said to be?
hydrophobic
What is the end process of fluid and material interactions?
disintegration
Term for the means of attaching two solids together?
Adhesion
Adhesion can occur by _________ _______ or sharing of _______
mechanical interlocking
electrons
Viscosity defined as?
resistance of a material to flow
We want substances with a ______ viscosity?
low
What is the term for the ability of a material to change viscosity with pressure?
thixotropic
What is the force that attracts molecules together?
cohesion
Hue = \_\_\_\_\_\_\_\_\_\_\_ Value = \_\_\_\_\_\_\_\_\_\_\_\_ Chroma = \_\_\_\_\_\_\_\_\_\_\_\_\_\_
color
brightness of color
vividness of the color
An _______ substance absorbs light?
opaque (dental material)
A _______ substance allows light to pass through?
transparent
Translucency is defined as?
the way light is affected in a substance
______ is when colors look different under different lights?
metamerism
Corrosion = ________ of the surface?
pitting
_______ is the surface discoloration due to the deterioration of a material?
tarnish
What 3 things can affect the mechanical properties of a material?
Load
Stress
Strain
Load on a material can cause _______ damage and _____ change?
structural
shape
Stress on a material is the amount of _____ applied to a ______ area?
force
specific
Stress = ____ / ______
force
area
Strain is an _______ rearrangement of _____ to adjust to ______
internal
atoms
stress
Strain = ________ / _________
deformation
length
Ability to resist pulling forces is termed?
tensile
Ability to resist pushing forces is termed?
Compressive
Ability to resist tearing forces parallel to each other is termed?
Shear
Compression = \_\_\_\_\_\_\_ Tension = \_\_\_\_\_\_\_\_\_\_ Shearing = \_\_\_\_\_\_\_\_ Torsion = \_\_\_\_\_\_\_\_
dent
stretch
bending
twisting
The elastic limit of a material measures?
stiffness of material OR the MAX stress without permanent deformation of the material
The point just before fracture is termed?
ultimate strength
The ability to be drawn into a “wire” is termed?
ductility
A material with low ductility is more ______?
brittle
The ability to be hammered/rolled thin without fracture/compression is termed?
malleability
Resilience is the energy necessary to cause _____ ______
permanent deformation
The ability to resist fracture is termed?
toughness
Define Creep?
gradual permanent change in dimension due to constant loading
What is created by repeated application of stress thus causing tiny “cracks” in the material?
fatigue
What are the 2 ways to measure the harness of a material?
Rockwell (RHN) #
Knoop (KHN) #
What hardness scale measure the depth of the indent and is mostly used on composite materials?
Rockwell
The KNOOP hardness scale measures the _____ of the _____?
length
diagonal
The KNOOP hardness scale is used with what materials?
metal and porcelain
Mouthguard material is made of _______ resin plastics?
semi-rigid
Mouthguard material is _____ and is softened upon _____?
thermoplastic
softened
What are 2 functions of temporary restorations?
maintain integrity and function of dentition
protect tooth from oral environment and bitting forces.
What type of temporary restorative material gives off heat and can damage the pulp and surrounding tissues?
Acrylic Resin
What type of resin material is used in dentistry and ALL other aspects of life. IE: molds of toys?
synthetic
How is an acrylic resin made?
adding methacrylic acid and heat to the monomers
What is the main type of intermediate restorative material (IRM) that is acidic but helps stimulate secondary dentin formation?
ZOE (zinc oxide eugenol)
ZOE material can’t be used under _______?
WHY?
composites
affects polymerization
ZOE is ______ in oral fluids and has poor ______ strength due to being very _____?
soluble
compressive
porous
