Quizlet Midterm Ver. 2

1. (1) The bite-wing tab is a heavy paperboard tab or loop fitted around a periapical film or sensor and used to stabilize the receptor during exposure. (2) The periapical receptor is oriented in the bite loop so that the tab portion extends from the white side (tube side) of the film or sensor.

a. Both statements are true.

b. Both statements are false.

с. The first statement is true; the second statement is false.

d. The first statement is false; the second statement is true.

A

2. —sizes of bite-wing receptors are available.

a. Two

b. Three

c. Four

d. Six

B

3. You have a 4-year-old boy in your chair, which size receptor will you need to use to take bite-wing images on him?

a. Size 0

b. Size 1

C. Size 2

d. Size 3

A

4. Which size bite-wing receptor may be placed in a horizontal or vertical position?

a. Size 0

b. Size 1

C. Size 2

d. Size 3

C

5. Your 35-year-old patient has clinical attachment loss in the posterior teeth. What type of bite-wing images should you take, and what size receptor should you use?

a. Horizontal; 1

b. Horizontal; 2

с. Vertical; 1

d. Vertical; 2

D

6. (1) Size 3 receptor can only be used for bite-wing images. (2) Size 3 receptor is the recommended size for adult bite-wing images.

a. Both statements are true

b. Both statements are false.

C. The first statement is true; the second statement is false.

d. The first statement is false; the second statement is true.

C

7. In the adult patient, which size receptor is recommended for bite-wing exposures?

a. Size 0

b. Size 1

C. Size 2

d. Size 3

C

8. When taking a molar bite-wing image, in order to follow rule number 5 of the bite-wing technique, receptor exposure, what must the mesial part of the PID cover?

a. Mesial of the mandibular first molar

b. Both first molars

c. Mesial of the mandibular second premolar

d. Both second premolars

D

9. The problem with a single bite-wing receptor per side for adult patients is increased

a. X-гау еxposure.

b. possibility of inciting the gag reflex.

с. overlapped contacts.

d. useful diagnostic information.

C

10. When determining vertical angulation, if the position-indicating device (PID) is positioned above the occlusal plane and the central ray is directed —the vertical angulation is termed —

a. upward; positive

b. downward; positive

с. upward; negative

d. downward; negative

B

11. Which of the following exposure sequences is recommended for the patient who requires both periapical and bite-wing images?

1. Bite-wing exposures

2. Anterior periapical receptors

3. Posterior periapical receptors

a. 1, 2, 3

b. 2, 1, 3

с. 2, 3, 1

d. 3, 1, 2

C

12. Vertical bite-wings are often used for patients with

a. mixed dentition.

b. extensive decay.

с. bone loss.

d. sealants.

C

13. What modification in technique is recommended when the patient has an edentulous space causing a problem with bite-wing receptor placement?

a. Skip the bite-wing receptor.

b. Place a cotton roll in the area of the missing tooth or teeth.

с. Have the patient hold the receptor in position with a hemostat.

d. Take a periapical receptor with a bite-block instead.

B

14. According to the text, the identification dot on the film in bite-wing placement

a. should be oriented "dot down."

b. should be oriented "dot distal."

C. should be oriented "dot up."

d. has no significance.

D

15. When taking a premolar bite-wing image, in order to follow rule number 5 of the bite-wing technique, receptor exposure, what must the mesial part of the PID cover?

a. Both premolars

b. Both canines

с. Mandibular canine

d. Mandibular premolar

B

16. Where should you position the mesial edge of the receptor when taking a premolar bite-wing image?

a. Midline of the maxillary canine

b. Midline of the mandibular canine

с. Mesial of the maxillary first premolar

d. Mesial of the mandibular first premolar

B

17. Where should you position the mesial edge of the receptor when taking a molar bite-wing image?

a. Distal of the maxillary first premolar

b. Distal of the mandibular first premolar

C. Midline of the maxillary second premolar

d. Midline of the mandibular second premolar

D

18. (1) Overlapped interproximal contacts are caused by improper vertical angulation. (2) To prevent overlap, the vertical angulation should be adjusted to +10 degrees.

a. Both statements are true.

b. Both statements are false.

c. The first statement is true; the second statement is false.

d. The first statement is false; the second statement is true.

B

19. What vertical angulation should you use when adjusting the PID to take bite-wing images with bite-tabs?

a. -10 degrees

b. 0 degrees

с. +5 degrees

d. +10 degrees

D

20. The contacts on your dental image are closed. You will need to take a retake. What should you do in order to achieve open contacts on your retake dental image?

a. Direct the PID at a +10 degree vertical angulation.

b. Direct the PID at a -10 degree vertical angulation.

C. Direct the PID through the contacts of the teeth.

d. Stabilize the receptor when the patient bites.

C

1. Which of the following areas would appear the most radiopaque on a dental image?

a. Composite

b. Amalgam

C. Air space

d. Enamel

B*

2. Density is defined as

a. a radiopaque image.

b. a radiolucent image.

c. the overall blackness or darkness of an image.

d. the difference in degrees of blackness between adjacent areas on a dental image.

C

3. You are showing your patient a bite-wing image. Your patient points to a portion of the tooth that is the most radiopaque and wants to know what it is. What portion of the tooth is your patient pointing to?

a. The enamel

b. The pulp

с. The denton

d. The periodontal ligament space

A

4. Radiolucent refers to that portion of a dental image that is

a. black.

b. white.

с. contains the tooth.

d. within the plastic base.

A

5. If the milliamperage is increased, the receptor density —-and the image appears —-

a. increases; lighter

b. increases; darker

с. decreases; darker

d. decreases; lighter

B

6. If the operating kiloyoltage is increased, the receptor density— because the average energy of the x-rays is raised.

a. increases

b. decreases

с. remains the same

d. is divided by two

A

7. You have to take retake a dental image on your patient because the image is too light and is undiagnostic. Which of the following could you change to produce an image with increased density?

a. Increasing the exposure time

b. Increasing the subject thickness

с. Decreasing the milliamperage

d. Decreasing the operating kilovoltage

A

The teeth on your patient's images appear very radiopaque and the periodontium and tissue appear very radiolucent. Your patient's dental image has

a. high density.

b. low density.

с. low contrast.

d. high contrast.

D

9. A dental image that has— is said to have high contrast.

a. a very dark overall appearance

b. a very light overall appearance

с. many shades of gray

d. very dark areas and very light areas

D

10. An increase in— temperature will result in a film with increased contrast.

a. development

b. water bath

C. fixer

d. room

A

11. When a high operating kilovoltage is used, (low/high) subject contrast and (many shades of gray/areas of black and white) are seen on the dental image.

A.Low subject contrast; many shades of gray

b. Low subject contrast; areas of black and white

C. High subject contrast; many shades of gray

d. High subject contrast; areas of black and white

A

12. The range of useful densities seen on a dental image is termed the

a. film contrast.

b. subject contrast.

c. scale of contrast.

d. kilovoltage peak.

C

14. The typical stepwedgę is constructed of

a. aluminum.

b. steel.

C. wood.

d. сopper.

A

17. Which of the following influencing factors would degrade sharpness?

(1) Smaller silver halide crystal size

(2) Larger silver halide crystal size

(3) Smaller focal spot

(4) Larger focal spot

a. 1 and 3

b. 1 and 4

с. 2 and 3

d. 2 and 4

D

16. The geometric characteristic of —refers to an image that appears larger than the actual size of the object it represents.

a. magnification

b. distortion

C. sharpness

d. parallax

A

15. A stepwedge will reveal that images taken at a higher kV will have —-versus images taken at a lower kV.

a. long-scale contrast

b. high contrast

с. only two densities

d. many areas of black and white

A

13. A stepwedge will reveal that images taken at a lower kV will have —-than images taken at a higher kV.

a. more shades of gray

b. higher contrast

c. lower contrast

d. both A and C

B

18. The primary factor that limits the size of the tungsten target is

a. the cost of the materials.

b. heat production.

c. the limited kinetic energy of the electrons.

d. the limited kinetic energy of the photons.

B

19. Which of the following factors would improve image sharpness?

a. Larger focal spot

b. Larger crystal size in the film

с. Smaller crystal size in the film

d. Patient movement during x-ray exposure

C

20. In order to use the paralleling technique when taking periapical images on your patient, you will need to place the receptor approximately an inch from the teeth. Which of the following will you need to do to decrease image magnification?

a. Increase target-receptor distance.

b. Decrease target-receptor distance.

с. Decrease source to object distance.

d. There is no change in magnification; therefore, no changes need to be made.

A

21. A longer position-indicating device (PID) results in

a. an increased target-receptor distance.

b. a more divergent x-ray beam.

с. more image magnification than when a shorter PID is used.

d. an increased object-receptor distance.

A

22. To minimize dimensional distortion, the object and receptor must be —one another.

a. perpendicular to

b. parallel to

c. at a 45-degree angle to

d. more than the length of the PID apart from

B

23. You are taking dental images on your patient. You have directed the position indicating device (PID) perpendicular to the tooth and the receptor. Which of the following would you minimize by doing this?

a. Sharpness

b. Grain size

с. Focal spot size

d. Dimensional distortion

D

25. You are in charge of monitoring the film badges. Film badges are checked on a quarterly basis. Your co-worker is 4 months pregnant. The badge registered 5.0 Sv for the previous quarter. Based on the National Council on Radiation Protection and Measurements (NCRP), what information should you give the dentist?

a. The reading is well below the allowable limit. Nothing needs to be done.

b. The reading is at the allowable limit. Nothing needs to be done.

C. The reading is at the allowable limit. She has reached her maximum dosage and cannot have any more exposure during the pregnancy.

d. She has exceeded her maximum dosage and cannot have any more exposure during the pregnancy.

D

26. You are 36 years old. What is your cumulative occupational dose recom- mended by the National Council on Radiation Protection and Measurements (NCRP)?

a. 360 millirems

b. 360 mSv

с. 180 millirems

d. 180 mSv

B

27. Your patient is a 5-year-old boy who you have been seeing since he was 3 years old. He is always eating candy and drinking cola beverages. Six months ago he had A, J, and T restored. One year ago he had B, I, and L restored. Which of the following should you do regarding taking radiographs?

a. Take bite-wings and occlusal radiograph today.

b. Insurance covers bite-wings once a year, take the dental images in 6 months.

с. Re-evaluate in 1 year for the need for dental images.

d. Dental images are taken every 2 years.

D

28. Your next patient is a 35-year-old man who you have been seeing for the past 10 years. The only treatment he has needed since coming to the dental practice has been his 6-month "prophys." He has no periodontal issues and is on a 6-month recall cycle. You last took four bite-wing images 1 year ago. Which of the following should you do?

a. Take bite-wings during this appointment.

b. Take the images in 6 months.

c. Take the images in 1 to 2 years.

d. No images will be needed for 5 years.

C*

20. (1) Radiation legislation varies greatly from state to state. (2) For example, in some states a dental radiographer must successfully examination before he or she may expose dental x-rays. complete a radiation safety

a. Both statements are true.

b. Both statements are false.

с. The first statement is true; the second statement is false.

d. The first statement is false; the second statement is true.

A

21. According to the current recommendations (2003) of the National Council on Radiation Protection and Measurements, the current MPD for occupationally exposed persons is —-/year.

a. 500 millirem

b. 5.0 rem

с. 50 rem

d. 5000 rem

B

22. According to the current recommendations (2003) of the National Council on Radiation Protection and Measurements, the current MPD for an occupationally exposed pregnant women is the equivalent of

A. 50 mSv/year.

b. 0.05 Sv per month.

с. 0.5 mSv/year.

d. 0.01 mSv/month.

C

23. The acronym for the maximum dose permitted in a year is

a. MPD-maximum permissible dose

b. MPD maximum possible dose

с. MAD -maximum accumulated dose

d. MAD maximum allowed dose

A

24. The ALARA concept states that all radiation must be kept

a. as long as readily achievable.

b. as low as reasonably allowable.

C. as low as reasonably achievable.

d. as long as reiably achievable.

C

15. Which of the following can you do after x-ray receptor exposure to reduce(s) the amount of x-radiation your patient receives?

a. Proper placement of the lead apron

b. Proper image retrieval

c. Proper instrument technique

d. Selecting proper exposure settings

C

16. The primary dictum of operator protection guidelines is that the operator must

a. remain in the room with the patient while the receptor is being exposed.

b. avoid the primary beam.

с. hold the receptor in the patient's mouth with their own finger.

d. hold the tubehead during x-ray exposure.

B

17. In order to avoid the primary beam while taking dental images, you should stand at a ——degree to —-degree angle to the beam.

a. 0; 45

b. 45; 90

с. 90; 135

d. 135; 180

C

18. Radiation monitoring can be used to protect the dental radiographer and includes monitoring of

a. equipment

b. personnel

c. both equipment and personnel

d. drywall for residual radiation

C

19. A film badge

a. is worn at waist level by the patient.

b. is worn at waist level by the operator.

с. is clipped to the shirt pocket of operator.

d. is clipped to the shirt pocket of the patient.

B

10. Which type of PID would be most effective in reducing patient exposure?

a. Conical

b. A 16-inch round PID

с. An 8-inch rectangular PID

d. A 16-inch rectangular PID

D

11. The thyroid collar

a. is recommended for all intraoral exposures.

b. is recommended for all extraoral exposures.

с. is placed over the patient's chest and lap and extends to protect the thyroid.

d. is recommended for both intraoral and extraoral exposures.

A

12. The lead apron

a. is recommended for intraoral exposures.

b. is not recommended for extraoral exposures.

с. is an option; use is not mandated by any state or federal law.

d. is used to protect the thyroid gland.

A

14. On some dental x-ray machines, only the — can be altered; the other parameters are preset by the manufacturer.

a. kilovoltage

b. exposure time

c. PID length

d. milliamperage

B

13. ***—-speed film is currently the fastest intraoral film available.

a. D

b. E

C. F

d. G

C

8. A rectangular collimator

a. restricts the beam 3 times more than a circular collimator.

b. restricts the beam less than a circular collimator.

с. decreases patient exposure considerably.

d. is considerably larger than a size 2 intraoral receptor.

C

9. Which of the following types of position-indicating devices (PIDS) produces scatter radiation?

a. Rectangular

b. Conical

c. Round

d. Square

D

7. A circular collimator produces a cone-shaped beam that is __________ inch(es) in diameter.
a. <1
b. 1.25
c. 2.75
d. 5.0

C

6. The collimator

a. is always round.

b. restricts the size and shape of the x-ray beam.

с. is a solid piece of aluminum.

d. is fitted within the copper stem beneath the molybdenum cup.

B

5. State and federal laws require that dental x-ray machines operating above 70 kVp have a minimum total (inherent plus added filtration) of —-mm of aluminum filtration.

a. 1.5

b. 2.0

с. 2.5

d. 5.0

C

1. Which of the following should you do prior to taking x-rays to protect your patient from radiation exposure?

a. Proper film processing

b. Proper prescribing of radiographs

c. A lead apron

d. A thyroid collar

B

2. The "Guidelines for Prescribing Dental Radiographs" state that

a. dentulous adult recall patients at increased risk for caries should have posterior bite-wing examinations at 12- to 24-month intervals.

b. X-rays are not taken on patients who are pregnant unless absolutely necessary.

с. edentulous adults should have posterior bite-wing examinations at 12- to 36-month intervals.

d. dentulous adult recall patients who are not at increased risk for caries should have posterior bite-wing examinations at 24- to 36-month intervals.

D

3. Inherent filtration in the dental x-ray tubehead

a. includes filtration that takes place when the primary beam passes through the glass window of the x-ray tube, the insulating oil, and the tubehead seal.

b. includes the placement of aluminum discs in the path of the x-ray beam between the collimator and the tubehead seal.

C. alone meets the standards regulated by state and federal law.

d. is equivalent to approximately 5.0 mm of aluminum.

A

4. Added filtration in the dental x-ray tubehead

a. refers to the placement of tungsten discs in the path of the x-ray beam between the collimator and the tubehead seal.

b. filters out shorter-wavelength x-rays from the x-ray beam.

c. results in a lower-energy beam.

d. results in a more penetrating useful beam.

D

The fundamental unit of matter is the

a.proton.

B.neutron.

C.electron.

d. atom.

D

2. The nucleus of an atom contains

A protons.

B. neutrons

C. protons and neutrons.

D.electrons.

C

3. Which subatomic particle carries a negative electrical charge?

a. A neutron

b. A proton

c. An electron

d. A nucleon

C

4. Which of the following elements is the simplest atom?

a. Hydrogen (H #1)

b. Helium (He #2)

C. Nitrogen (N #7)

d. Oxygen (O #8)

A

Which of the following statements is true of orbits or shells in the atom?

a. Protons travel around the nucleus in well-defined shells.

b. An atom contains innumerable shells.

C. The energy level within each shell is the same.

d. The orbiting shell closest to the nucleus has the highest energy level.

D

6. The binding energy or binding force of an electron is

a. determined by the distance between the neutrons and protons within the nucleus.

b. determined by the distance between the orbiting electrons and the nucleus.

c. weaker for electrons located in inner shells than in outer shells.

d. determined by the atomic number.

B

Which of the following statements is true of ionization?

a. An atom that gains an electron will have a negative charge.

b. An atom that loses an electron will have a negative charge.

C. An atom that loses an electron will have a positive charge.

d. An atom that gains an electron has a negative charge, and an atom that loses an electron has a positive charge.

D

8. An ion pair results when

a. a proton is removed from an atom.

b. an electron is removed from an atom.

с. a neutron is removed from an atom.

d. two atoms share a pair of electrons.

B

9. (1) Radiation is the emission and propagation of energy through space or a substance in the form of waves or particles. (2) Radioactivity can be defined as the process by which certain unstable atoms or clements undergo spontaneous disintegration, or decay, in an effort to attain a more balanced nuclear state.

a. Both statements are true.

b. Both statements are false.

с. The first statement is true; the second statement is false. '

D. The first statement is false; the second statement is true.

A

10. The spontaneous emission of radiation from the disintegration of unstable atomic nuclei is

a. beta particle decay.

b. radiation.

C. radioactivity.

D. alpha particle decay.

C

1. Which of the following statements is true of ionizing radiation?

a. It is radiation that is capable of producing ions by removing or adding an electron to an atom.

b. It is strictly an electromagnetic radiation and does not involve particles that have mass.

C. It is strictly particulate radiation and cannot travel as waves.

d. It can only travel at the speed of light.

A

12 Cathode rays are derived from which of the following types of particulate radiation?

a. Electrons

b. Alpha particles

с. Protons

d. Neutrons

A

13 Electromagnetic radiations

a. are entirely human-made.

b. include x-rays and visible light.

C. are a form of particulate radiation.

d. have mass.

B

14. Which of the following forms of electromagnetic radiation are capable of ionization?

a. Radio waves

b. Visible light

C. Ultraviolet light

d. X-rays

D

15. Photons are

a. bundles of energy with mass and weight.

b. bundles of energy that travel at the speed of sound.

C. a component of the particle concept of electromagnetic radiation.

d. a component of the wave concept of electromagnetic radiation.

C

16. Which of the following statements is true of the wave concept of electro- magnetic radiation?

a. Wavelength refers to the speed of the wave.

b. Velocity refers to the number of wavelengths that pass a given point in a certain amount of time

c. Frequency is defined as the distance between the crest of one wave and the crest of the пеxt.

d. Frequency and wavelength are inversely related.

D

17. Which of the following forms of electromagnetic radiation has the shortest wavelength?

a. Radio wave

b. Television wave

C. Radar wave

d. Dental x-ray wave

D

18. Which of the following components of the x-ray machine would have two indicator lights?

a. X-ray tube

b. X-ray tubehead

C. The control panel

d. The extension arm

C

19 Heat is a byproduct of x-ray production. Which component of the x-ray tubehead dissipates the heat created by the production of x-rays?

a. Metal housing

b. Insulating oil

c. Aluminum discs

d. Lead collimator

B

20. Your patient had x-rays taken in her previous dental office. She notices that the long metal tube at the end of the x-ray head is longer than it was at the other office. What explanation would you give for the purpose of the tube, or cone, attached to the x-ray head?

a. It surrounds the x-ray tube, protects the x-ray tube, and grounds the high-voltage components.

b. It seals the oil in the tubeh and acts as a filter to the x-ray beam.

с. It filters out the nonpenetrating, longer-wavelength x-rays.

d. It aims and shapes the x-ray beam.

D

21. Within the x-ray tube, electrons are generated by the

a. tungsten filament in the cathode.

b. tungsten filament in the anode.

c. molybdenum cup.

d. copper stem.

A

22. The purpose of the anode is to

a. produce electrons when heated.

b. convert electrons into x-ray photons.

C. absorb heat created by the production of x-rays.

d. filter out nonpenetrating, longer-wavelength x-rays.

B

23. In the dental x-ray tube, the number of electrons created is controlled by

a. alternating curent.

b. direct current.

c. milliamperage.

d. kilovoltage.

C

24. Your x-ray machine runs off 110 volts. Theoretically what would occur if there was no step-down transformer in the x-ray control panel?

a. Too few electrons would be produced for the purpose of dental x-rays. 65,000 to 100,000 volts are required to heat the tungsten filament

. b. Too few electrons would be produced for the purpose of dental x-rays. 50,000 to 75,000 volts are required to heat the tungsten filament.

C. Too many electrons would be produced for the purpose of dental x-rays. Only 3-5 volts are required to heat the tungsten filament.

d. There would be no interruption in function of the machine.

C

25. Thermionic emission of electrons occurs at the

a. tungsten filament in the anode.

b. tungsten filament in the cathode.

с. copper stem.

d. molybdenum cup.

B

26. Approximately what percentage of the kinetic energy of the electrons is converted to x-rays at the anode?

a. Less than 1%

b. 25%

C. 50%

d. 100%

A

27, The lead collimator

a. carries away the heat produced during the production of x-rays.

b. permits a small number of x-rays to exit from the x-ray tube.

c. filters the longer-wavelength x-rays from the beam.

d. restricts the size of the x-ray beam.

D

28. Which of the following statements is true of characteristic radiation?

a. It is also known as braking (bremsstrahlung) radiation.

b. It only occurs at 70 kV and above.

с. It is the source of the majority of x-rays that are produced.

d. The high-speed electron passes close to the nucleus or hits the nucleus of the tungsten atom.

B

29. Which form of the x-ray beam is most detrimental to the patient and operator?

a. Primary radiation

b. Secondary radiation

C. Scatter radiation

d. Useful beam

C