Materials Exam 1 Chapters 1,3,9,20
An example of a physical of a physical property is: A. Density B. Strength C. Stiffness D. Setting reaction
A
The design of a cavity preparation aids in the retention of a restoration. The walls of a amalgam preparation diverge while in the walls of an inlay converge. A. The first statement is true, second is false B. The first statement is false, second is true C. Both are true D. Both are false
A
Using Figure 1.9A and D, which of the following guest describes the roots of the teeth? A. Calculus is visible on the distal of tooth #2 B. Calculus is visible on several roots C. The roots are radiographically foreshortened D. The roots are radiographically elongated
A
Which of the following defines the modulus of elasticity? A. Stress/strain B. Stress2/strain C. Strain/strain D. 2x stress/strain
A
Which of the following restorations is utilized when a substantial amount of a tooth is missing? A. Crown B. Pontic C. Implant D. Fixed partial denture
A
An amalgam restoration located on the gingival third of tooth #3 would be a Class __ restoration. A. I B. II C. III D. IV E. V F. VI
E
A drop of water on a popsicle is an example of: A. Poor wetting (low contact angle) B. Good wetting (high contact angle) C. Good wetting ( low contact angle) D. Poor wetting (high contact angle)
C
All of the following are reasons for a dental hygienist to have knowledge and understanding of dental materials EXCEPT: A. Explaining the different types of restorative materials available to the patient B. Assessing the patients oral condition C. Deciding which material is best for the patients restoration D. Understanding the behavior of dental materials
C
Cooled material will contract, and heated materials will expand. A measurement of this change in volume in relation to change in temperature is called the coefficient of thermal expansion. A. the first statement is true, second is false B. The first statement is false, second is true C. Both are true D. Both are false
C
Medical devices are grouped into three categories according to the Medical Device Amendment of 1976. Which of the following devices is most regulated? A. I B. II C. III D. IV
C
The ability of a material to dissolve in a liquid is termed: A. Viscosity B. Water sorption C. Solubility D. Wetting
C
The biologic nature of the oral environment and the size3 of the oral cavity restrict the use of dental materials. One restriction is the degradation of restorations. A. The first statement s true, second is false B. The first statement is false, second is true C. Both are true D. Both are false
C
The modulus of elasticity is an indication of what property of a material? A. Resilience B.Strength C. Stiffness D. Tension
C
Which of the following oral tissues provides feedback to the individual regarding the forces placed on the tooth? A. Pulp B. Dentin C. Periodontium D. Gingival tissue
C
A twisting force is termed: A. Compression B. Shear C. Tension D. Torsion E. Bending
D
An example of an indirect restorative material would be: A. Amalgam B. Glass ionomer cement C. Composite D. Ceramic (porcelain)
D
The tightening of a guitar string is an example of which of the following stresses? A. Compression B. Torsion C. Shear D. Tension
D
When the temperature changes in the mouth, the teeth and most restorative materials expand and contract by the same amount. No leakage occurs around the restoration. A. The first statement is true, second is false B. The first statement is false, second is true C. Both are true D. Both are false
D
Elasticity is an example of which of the following properties? A. Physical B. Mechanical C. Chemical D. Biologic
B
If a restoration is fabricated on a replica (positive reproduction) of a patients teeth, it is referred to as a : A. Student model B. Cast C. Diagnostic cast D. Any of the above terms may be used
B
In the United States, standards for dental materials are developed and administered by the: A. FDA (Food and Drug Administration) B. ADA (American Dental Association) C. AADR (America Association for Dental Research) D. OSHA (Occupational Safety and Health Administration)
B
When a stress is induced in a material that is greater than the materials yield strength, the stress is ___ proportional to the strain, and the material does not return to its original shape. A. Always B. No longer C. Equally D. None of the above
B
