Dental Materials Chapter 2: Oral Environment and Patient Considerations

Review questions & vocab

The safe interaction of a dental material with the rest of the body is defined as the material's

Biocompatibility

What does the study of dental materials include knowledge of?

Causes for the failure of the material

What is the internal reaction to an externally applied force called?

Stress

When increasingly higher forces are applied to a material, it will eventually fracture, and the point of fracture is called

Ultimate strength

Material subject to repeated stresses, such as in mastication, may be subject to a fracture due to

Fatigue Failure

Which of the following restorative materials is the most soluble?

a. amalgam

b. glass ionomer

c. porcelain

d. acrylic

Glass ionomer

Corrosion is of greatest concern for which of the following restorative materials?

a. gold

b. composite resin

c. amalgam

d. porcelain

Amalgam

What is the surface discoloration of a metal restoration called?

Tarnish

Restorative materials with values of thermal conductivity similar to enamel include:

a. gold

b. composite resin

c. amalgam

d. silver

Composite resin

Susan has just had an MOD amalgam placed on tooth #30. When biting, this tooth is in contact with a gold crown on tooth #3. Susan complains of an electric shock sensation and metal taste. This is most likely due to

A. galvanism

B. corrosion

C. Tarnish

D. Metamerism

Galvanism

Microleakage may be responsible for

A. recurrent decay

B. marginal staining

C. postoperative sensitivity

D. all of the above

All of the above

What may the excessive film thickness of cements cause?

a. an increase in retention

b. a decrease in marginal leakage

c. improper seating of the restoration

d. fracture of the restoration

Improper seating of the restoration

Color shades can vary depending on the incident light or source of light. This effect is called

a. spectrum

b. chroma

c. meniscus

d. metamerism

Metamerism

What is the term used to describe the intensity of color?

a. hue

b. value

c. chroma

d. opacity

Chroma

What is an oral biofilm?

Is a complex organization of microorganisms on oral surfaces and restorations

An adhesive that spreads on the surface of the tooth and restoration will be more ______.

Retentive

Preventative materials…

prevent dental related disease or trauma

Restorative materials….

Repair or replace a tooth structure

Direct restorations are…

shaped, molded, and hardened directly inside the patient’s mouth in a single appointment. Typically composite fillings.

Indirect restorations are ….

custom-made outside the patient’s mouth in a dental lab or by a computer milling machine, then glued onto the tooth at a separate visit. Typically porcelain crowns or veneers.

Galvanism is

an electrical current transmitted between 2 dissimilar metals in a solution of electrolytes

Galvanic shock is

the result in stimulation of pulp

Dimensional change is

a change in the size of matter, caused by heating and contraction caused by cooling.

Coefficient of thermal expansion is

the measurement of change in volume or length in relation to change in temperature.

Thermal conductivity is

the rate at which heat flows through a material over time.

Viscosity is

the ability of a liquic material to resist flow.