Primary Bonds
ionic bonds, covalent bonds, metallic bonds.
Secondary Bonds
hydrogen bonds, Van der Vaals bonds.
Brittleness
hard and likely to to crack.
Density
the measure of the weight of a material compared with its volume.
Hardness
the resistance of a solid to penetration.
Ultimate Strength
the maximum amount of stress a material can withstand without breaking.
Elasticity
the ability of a material to recover its shape completely after deformation from an applied force.
Stiffness
a material's resistance to deformation.
Proportional Limit
the greatest stress a structure can withstand without permanent deformation.
Resilience
the resistance of a material to permanent deformation.
Toughness
the ability of a material to resist fracture.
Ductility
the ability of an object to be pulled or stretched under tension without rupture.
Malleability
the ability to be compressed and formed into a thin sheet without rupture.
Edge Strength
the strength of a material at fine margins.
Viscosity
the ability of liquid material to flow.
Thixotropic
property of a liquid to flow more readily under mechanical force.
Direct Restorative Material
restorations placed directly into a cavity preparation.
Indirect Restorative Material
materials used to fabricate restorations outside the mouth that are subsequently placed into the mouth.
Mixing time
the amount of time alloted to manipulate the material in the mouth.
Initial set time
the time at which the material can no longer be manipulated in the mouth.
Final set time
the time at which the material has reached its ultimate state.
Chemical Set Material
materials that set through a timed chemical reaction with the combination of a catalyst and base.
Light-Activated Materials
materials that require a blue light source to initiate a reaction.
Dual Set Material
materials that polymerize by a chemical reaction when the material is mixed with a catalyst or intiated by exposure to the blue light, or by a combination of chemical or light reaction.
Shelf life
the useful life of a material before it deteriorates or changes in quality.
1) A defining characteristic of a solid is that it has
a. Shape and volume
b. Shape only
c. Neither shape nor volume
d. Volume but not shape
a. Shape and volume
2) The most primary bonds
a. Have random form
b. Have regular crystalline structures
c. Are amorphous
d. Have mixed physical structure
b. Have regular crystalline structures
3) The correct term for describing when an applied stress is proportional to a resulting strain is
a. Toughness
b. Elasticity
c. Ultimate Strength
d. Ductility
c. Ultimate Strength
4) When the weight of a material increase in relationship to its volume, it is describes as
a. Elastic
b. Resilient
c. Dense
d. Hard
c. Dense
5) Hardness determines the material's ability to
a. Deform and object
b. Break an object
c. Be easily compressed
d. Penetrate an object
d. Penetrate an object
6) When deformation is not permanent and a material recovers, it has good
a. Toughness
b. Elasticity
c. Malleability
d. Ductility
b. Elasticity
7) Resistance to flow is known as
a. Viscosity
b. Film thickness
c. Density
d. Curing
a. Viscosity
8) Thixotropic materials are those that
a. Have poor viscosity
b. Flow under mechanical forces
c. Flow at higher temperatures
d. Flow at lower temperature
b. Flow under mechanical forces
9) Indirect restorative materials would include all of the following except
a. Porcelain crowns
b. Amalgam restoration
c. Gold crowns
d. Porcelain veneers
b. Amalgam restoration
10) Mixing time is the length of time from
a. The beginning of mixing time to the end of setting time.
b. The beginning of mixing time to the end of the initial set time
c. The beginning of mixing to the beginning of working time.
d. The beginning of mixi
c. The beginning of mixing to the beginning of working time.
11) A material mixed slowly on a cooled glass surface will
a. Have a shorter working and setting time.
b. Have a longer setting and working time.
c. Have a shorter working and longer setting time.
d. Have a longer working and shorter setting time.
b. Have a longer setting and working time.