Dental Materials Flashcards
chemical attraction between unlike molecules
adhesion
chemical attraction between like molecules
cohesion
index which indicates how one material reacts to temperature extremes in relation to another
Coefficient of thermal expansion
force at which a material breaks under pressure
compressive strength
slow dimensional change caused by compression
creep
ability to undergo change of form without breaking
ductility
materials ability to recover its initial shape after undergoing force
elasticity
electrical current generated by dissimilar metals in an acidic environment
galvanism
process of gelling (solidification by cold)
gelation
volumetric weight of one cubic cm or mm of water
gram
absorption of a solvent by a gel
imbibition
materials capacity to be shaped by force or pressure
malleability
linking, branching, or cross linking of smaller molecules
polymerization
force at which material cannot return to its original shape
proportional limit
contraction of a gel due to loss of a solvent
syneresis
force need to stretch material to point of fracture
tensile strength
resistance to flow
viscosity
change a materials components its properties change
truism
Mat - an alloy of mercury with silver, copper, tin and zinc
amalgam
Mat - added to amalgam to minimize corrosion (gamma 2 phase eliminated)
copper
polish - amalgam and gold
tin oxide
polish - for composites
diamond
used to SEAL dentin to MEDICATE dental pulp
liners
liner that stimulates reparative dentin formation
calcium hydroxide
used to provide thermal INSULATION or mechanical PROTECTION for dental pulp
bases
cement - exothermic reaction on mixing
zinc
cement - binds to dentin, thermal expansion, class V restorations
glass ionomer
cement - temporary, orange solvent used to clean contaminated instruments
ZOE - zinc oxide eugenol
types of impression materials (2)
rigid - inelastic
flexible - elastomeric (aqueous/non-aqueous)
Mat - flexible, aqueous, undergoes physical reaction; temp dependent
Hydrocolloid (agar)
Mat - flexible, aqueous, undergoes chemical reaction; Not temp dependent- but temp speeds or slows setting, need for fluff
Irreversible Hydrocolloid (alginate)
Mat - flexible, non-aqueous, unstable in presence of moisture
polyether rubber
Mat - flexible, non-aqueous, addition reaction silicone
vinylpolysiloxane
Mat - primarily made of paraffin, used to modify the shape of impression tray and cushion braces
Utility wax
Leading cause of implant failure
mobility - due to inadequate bone, lack of osseointegration, peri-implantitis
Active ingredient in Tartar control toothpaste; leading cause of dentinal hypersensitivity
pyrophosphate
Active ingredient in Gum care toothpaste; antimicrobial agent
triclosan
Active ingredient in Desensitization toothpastes (3)
potassium nitrate, sodium citrate, strontium chloride
Highly effective Desensitizers professionally placed (2)
potassium oxalate, fluoride varnish
Active ingredient in Vital bleaches (home bleach) (2)
carbamide peroxide, hydrogen peroxide
GV Black Class 1
pits and fissures
GV Black Class 2
posterior proximals
GV Black Class 3
anterior proximals
GV Black Class 4
anterior proximals including incisal edge
GV Black Class 5
facial or lingual cervical third
GV Black Class 6
cusp tips and incisal edges
Mat - added to non-metal restorative materials to appear radiopaque in X-rays (2); if not added X-ray will appear radiolucent and look like decay
barium, strontium
amount of time used to etch
20 seconds
time before stone cast is removed from an alginate impression
30-60 minutes
Brinell and Knoop test used to determine
hardness