Test Bank on Essentials of Dental Radiography 9th Edition By Evelyn Thomson, Orlen Johnson

Test Bank on Essentials of Dental Radiography 9th Edition By Evelyn Thomson,Orlen Johnson Chapter 1 Multiple Choice 1. Who was awarded the first Nobel Prize for physics in 1901, for his experimental work with radiation? a) W. J. Morton b) O. Walkhof c) W. D. Coolidge d) W. C. Roentgen 2. Who is credited with introducing the bitewing radiograph? a) F. W. McCormack b) H. R. Raper c) G. M. Fitzgerald d) C. E. Kells 3. Who developed the hot cathode ray tube? a) W. D. Coolidge b) W. A. Price c) H. R. Raper d) W. H. Rollins 4. The development of radiation protection as a science is credited to: a. Cieszyński. b. W. D. Coolidge. c. W. H. Rollins. d. F. Mouyen. 15. What New Orleans dentist first made practical use of x-rays in the treatment of dental patients? a. H. R. Raper b. G. M. Fitzgerald c. F. Mouyen d. C. E. Kells 6. Early researchers working in the field of radiography were not aware that continued exposure to x-rays produced accumulations of radiation efects in the body because x-rays are invisible. a. Both the statement and reason are correct and related. b. Both the statement and reason are correct but NOT related. c. The statement is correct, but the reason is NOT. d. The statement is NOT correct, but the reason is correct. e. NEITHER the statement NOR the reason is correct. 7. The most significant advancement in the early days of radiography came in 1913 when W. D. Coolidge: a. became the first to alert the profession of the dangers of radiation exposure and advocated for the science of radiation protection. b. exposed a prototype of a dental radiograph, setting the stage for preventive oral health care. c. developed a variable, high kilovoltage x-ray machine compatible with the paralleling technique. d. introduced an x-ray tube that allowed for an x-ray output that could be predetermined and accurately controlled. 8. The first dental radiograph was produced using an exposure time of: a. 0.5 second. b. 1 minute. c. 5 minutes. d. 25 minutes. e. 1 hour. 29. What component of the dental x-ray machine best limits the size of the x-ray beam to the approximate size of the image receptor? a. A pointed cone b. An open round cylinder c. A rectangular PID d. A slit collimator 10. Panoramic radiology became popular in the: a) 1930s. b) 1940s. c) 1950s. d) 1960s. e) 1970s. 11. Which of the following is NOT true regarding cone beam volumetric imaging? a) It images a single selected plane of tissues. b) It is based on computed tomography. c) It uses less radiation than a panoramic radiograph. d) It is designed specifically for imaging dental applications. e) It is purported to become the gold standard for imaging certain oral conditions. 12. Early dental film required long exposure times because: a) it was hand-wrapped. b) the emulsion was only on one side. c) glass plates were used as the base. d) the packets were not moisture resistant. 13. Each of the following is an advantage of digital imaging EXCEPT one. Which one is the EXCEPTION? 3a) It reduces radiation over film-based radiography. b) It eliminates the need for the darkroom and processing chemistry. c) It allows the use of pointed cones without radiation hazards. d) It avoids the need for disposal of hazardous materials such as lead foils from film packets. e) It produces enhanced two- and three-dimensional images. 14. The KTbisecting technique was the first and earliest radiographic technique for exposing intraoral radiographs because the bisecting technique is based on the rule of isometry. a) Both the statement and reason are correct and related. b) Both the statement and reason are correct but NOT related. c) The statement is correct, but the reason is NOT. d) The statement is NOT correct, but the reason is correct. e) NEITHER the statement NOR the reason is correct. 15. The KTparpaparalleling technique is taught in all dental assisting, dental hygiene, and dental schools because it is the technique of choice for imaging intraoral radiographs. a) Both the statement and reason are correct and related. b) Both the statement and reason are correct but NOT related. c) The statement is correct, but the reason is NOT. d) The statement is NOT correct, but the reason is correct. e) NEITHER the statement NOR the reason is correct. 16. The rule of isometry is the basis for what dental radiographic technique? a) Bisecting b) Paralleling c) Panoramic d) Digital 4e) Computed tomography 17. Each of the following is a potential use of dental radiographs EXCEPT one. Which one is the EXCEPTION? 5a) Diagnosing dental caries b) Evaluating development of dentition c) Detecting missing teeth d) Assessing patient self-care e) Evaluating trauma to teeth and supporting bone 18. Producing radiographs of the teeth and/or the oral cavity is called: a) Radiation producing. b) Radiology. c) Roentgenograph. d) X-raying. e) Radiography. 19. Dental assistants and dental hygienists meet an important need by providing each of the following EXCEPT one. Which one is the EXEPTION? a) Exposing radiographs b) Processing radiographs c) Mounting radiographs d) Prescribing radiographs e) Interpreting radiographs 20. The positioning indicating device (PID) is sometimes called a “cone” because the PID of early dental x-ray machines was of a pointed shape. a) Both the statement and reason are correct and related. b) Both the statement and reason are correct but NOT related. 6c) The statement is correct, but the reason is NOT. d) The statement is NOT correct, but the reason is correct. e) NEITHER the statement NOR the reason is correct. True/False 1. William Herbert Rollins was awarded the first Nobel Prize for physics. 2. C. Edmund Kells encouraged the practical use of radiographs in dentistry. 3. The radiographer should help the patient hold the image receptor in place during exposure. 4. In the early 1900s dental patients would have to be sent to hospitals or a physician’s office to have a dental radiograph exposed. 5. Early dental x-ray machines were an electrical hazard. 6. Pointed cones should be used to direct radiation from the x-ray tube to the patient. 7. Dental x-ray film available today is coated with emulsion on both sides. 8. The bisecting technique is the technique of choice for intraoral radiography. 9. Dental radiography supplements visual and physical examination to provide a quality evaluation of a patient. 10. Digital imaging systems can reduce radiation dosage more than film-based radiography. 11. A radiograph is an image produced by exposure to x-rays. 12. Computed tomography eliminates the use of radiation to produce an image. 13. Digital imaging replaces the conventional dental x-ray machine. 14. The paralleling technique is based on the rule of isometry. 15. The PID is used to direct the useful beam of radiation. 16. X-radiation was discovered when Roentgen was working with a Crookes tube. 17. Roentgen named his discovery the roentgen ray. 718. The x-radiation output of the Crookes tube (named after the English chemist William Crookes) could be predetermined and accurately controlled. 19. Early scientists and researchers working in the field of radiography were not aware that continued exposure produced accumulations of radiation efects in the body. 20. In the early 1900s, it was common practice for the radiographer to help the patient hold the film in place while making the exposure. Short Answer 1. Who first determined that x-rays would play a role in dentistry? 2. Who is considered to be the first advocate for the science of radiation protection? 3. Who developed the hot cathode ray tube? 4. Which radiograph displays the entire dentition and surrounding structures? 5. What is the technique of choice for intraoral radiography? 6. In dental digital imaging systems, what replaces film? 7. What medical imaging modality records a selected plane of tissues? 8. What is the name of the device that functions to direct the x-ray beam toward the patient? 9. What is the purpose of studying the history of radiography and dental radiography? 10. What are the two techniques for exposing intraoral dental radiographs? Chapter 2 Multiple Choice 1. Each of the following is a form of energy EXCEPT one. Which one is the EXCEPTION? a) Heat 8b) Water c) Light d) X-radiation 2. What is the maximum number of electron shells (energy levels) an atom can have? a) 7. 1 b) 8. 3 c) 9. 5 d) 7 3. Each of the following is a form of ionizing radiation EXCEPT one. Which one is the EXCEPTION? a) Cosmic rays b) X-rays c) Radio waves d) Gamma rays 4. Each of the following statements about electromagnetic radiations is true EXCEPT one. Which one is the EXCEPTION? a) They have a negative electrical charge. b) They have no mass. c) They pass through space as particles and in a wave-like motion. d) They have no weight. 5. Which of the following statements about x-rays is NOT true? a) They travel at the speed of light. b) They are invisible. c) They have no mass. 9d) They travel in convergent lines. 106. Which one of these is NOT a Système International (SI) unit of measurement? a) Sievert b) Roentgen c) Coulombs per kilogram d) Gray 7. The Système International unit for measuring absorbed dose is the a) Gray b) Sievert c) Rad d) Rem 8. The greatest exposure to ionizing radiation to the population comes from a) Medical x-rays b) Occupational exposure c) Dental x-rays d) Background radiation 9. The speed of a wave is its a) Wavelength b) Velocity c) Frequency d) Photon 10. The majority of x-rays produced by dental x-ray machines are formed by: a) Characteristic radiation b) Radionuclide decay 11c) Bremsstrahlung radiation 12d) Coherent scattering 11. Radiation is best described as a: a) substance that occupies space. b) resistor of heat. c) type of electricity. d) movement of energy. 12. The smallest particle of a substance that still retains the properties of that substance is a/an: a) atom. b) electron. c) neutron. d) molecule. 13. The emission and movement of electromagnetic or particulate energy through space is known as: a) ionization. b) radiation. c) radioactivity. d) the formation of ion pairs. 14. The measure of the number of waves that pass a given point per unit of time is known as the: a) angstrom unit. b) wavelength. c) frequency. d) velocity. 15. When x-rays pass through matter, which interaction results in x-rays being scattered in all directions? a) The coherent efect 13b) The photoelectric efect c) The Compton efect 16. The amount of energy deposited in the teeth or soft tissue by any type of radiation is called the: a) exposure amount. b) absorbed dose. c) dose equivalent. d) background radiation. 17. The units used to measure the dose equivalent of radiation is the: a) Gray (Gy). b) Sieverts (Sv). c) Coulombs per kilogram (C/kg). d) Roentgens (R). 18. The sievert and rem are units of measurement for: a) the radiation exposure in the air. b) the amount of energy absorbed by tissues. c) the comparison of biological efects. d) All of the above. 19. A weighting (qualifying) factor is used to determine which of the following? a) coulombs per kilogram b) sievert c) roentgen d) gray 20. The wavelength determines the energy and penetrating power of the radiation. The longer the wavelength, the higher the energy of the radiation. 14a) The first statement is true. The second statement is false. b) The first statement is false. The second statement is true. c) Both statements are true. d) Both statements are false. True/False 1. Matter is defined as the ability to do work and overcome resistance. 2. An atom is the smallest part of an element that still retains properties of that element. 3. Electrons have a positive charge. 4. The inner-most electron shell in an atom is the K shell. 5. Dental x-rays do not involve the use of radioactivity. 6. X-rays travel at the speed of sound. 7. Wavelength and frequency are directly related. 8. X-rays make the materials they pass through radioactive. 9. The photoelectric efect is an all-or-nothing energy loss. 10. The Compton efect causes x-rays to be scattered in all directions. 11. The number of electrons in the nucleus of an element determines its KTatomic number. 12. Background radiation includes cosmic rays from outer space, naturally occurring radiation from the earth, and radiation from radioactive materials. 13. Kinetic energy is the internal energy within the atom that holds its components together. 14. The total number of protons in the nucleus of an atom determines the atomic number. 15. Energy that travels in a diferent direction than that of the original x-ray is collectively called “secondary radiation.” 16. The majority of x-rays produced by dental x-ray machines are formed by general (bremsstrahlung) radiation. 1517. The electromagnetic spectrum arranges energy types by decay rates. 18. X-rays of high energy and extremely short wavelengths are classified as hard radiation. 19. Ionizing radiation is energy that is capable of producing ions. 20. Electromagnetic radiation is propelled through space as both a particle and a wave. Short Answer 1. What is defined as anything that occupies space and has mass? 2. What are the positively charged particles in the nucleus of an atom called? 3. What is the term for atoms that have gained or lost electrons and electrical neutrality? 4. What is the name of the process in which unstable elements undergo spontaneous decay in order to become stable? 5. What is the term for bundles of energy that travel through space at the speed of light? 6. What is the speed of a wave called? 7. When radiation has great penetrating power it is called what? 8. Should you wait 30 seconds after making an exposure before entering the room? 9. People living on the Colorado plateau receive a higher dose of what type of radiation than people living in Philadelphia? 10. One gray equals how many rads? Chapter 3 Multiple Choice 161. Dental x-ray machines contain each of the following components EXCEPT one. Which one is the EXCEPTION? a) Control panel b) Extension arm c) Radioactive material d) Tube head 2. Which regulating device on the control panel measures the amount of current passing through the wires of the circuit? a) The timer b) The line switch c) The kVp selector d) The mA selector 3. Each of the following conditions must exist for x-rays to be produced EXCEPT one. Which one is the EXCEPTION? a) A target capable of stopping the electrons b) An air-filled glass tube c) High voltage to impart speed to the electrons d) A source of free electrons 4. Which of the following is NOT a function of the tube head? a) It allows all radiation to exit. b) It provides grounding for the electrical components. c) It protects the x-ray tube from accidental damage. d) It prevents overheating of the x-ray tube. 5. The anode is composed of the focusing cup and the filament, and must be charged negative during x-ray production. a) The first part of the statement is correct, the second part of the statement is NOT correct. 17b) The first part of the statement is NOT correct, the second part of the statement is correct. c) Both parts of the statement are correct. d) Both parts of the statement are NOT correct. 6. How many electrical circuits are used in a dental x-ray machine? a) One b) Two c) Three d) Four 7. Sixty (60) impulses is equivalent to: a) 1/6 second. b) 1/10 second. c) ½ second. d) 1 second. 8. The intensity of the x-ray beam is afected by each of the following EXCEPT one. Which one is the EXCEPTION? a) Target size b) Kilovoltage c) Exposure time d) Milliamperage 9. A 1/10-second exposure equals how many impulses? a) 4 b) 6 c) 10 d) 60 1810. Which of these statements is FALSE? a) The positive anode and negative cathode are sealed within the x-ray tube. b) The control panel may be integrated with the x-ray machine tube head support. c) The exposure button should be on the end of a 3-foot timer cord. d) The x-ray tube contains a target capable of stopping the electrons. 11. The duration of an x-ray exposure is determined by which control? a) The timer b) The line switch c) The kVp selector d) The mA selector 12. The filament and target are made out of tungsten because it: a) produces fewer electrons. b) prevents electrons from being liberated. c) withstands high temperatures. d) ensures that x-rays are projected in one direction. 13. Which transformer corrects minor fluctuations in the current flowing through the wires? a) The step-up transformer b) The step-down transformer c) The autotransformer 14. X-rays originate at the: a) cathode. b) port. c) focusing cup. d) focal spot. 19e) Amperage measures the electric potential or force that moves electrons along a conductor. 15. Increasing the force with which the electrons move increases the penetrating potential of the x- ray beam. a) The first statement is true. The second statement is false. b) The first statement is false. The second statement is true. c) Both statements are true. d) Both statements are false. 16. Which of the following best describes how x-rays are actually produced in the dental x-ray tube? a) Radioactive particulate matter undergoes controlled disintegration. b) Electrical current passes through an oil mixture, creating minute explosions. c) Low milliamperage current is transformed to high kilovoltage current. d) High-speed electrons collide with target material electrons. 17. What percent of the kinetic energy inside the x-ray tube is actually converted to x-radiation? a) 99 percent b) 50 percent c) 25 percent d) 1 percent 18. Increasing which of the following would best increase the number of electrons flowing through the dental x-ray electrical circuit? a) Impulses b) Kilovoltage c) Milliamperage d) PID length 19. Which of the following removes the soft x-rays for the /KTx-ray beam as it exits the port? 2020. The positioning indicating device (PID) a) The collimator b) The filter c) The transformer 21. How does the radiographer know when the x-ray exposure cycle is complete? a) When the deadman switch cannot be depressed b) When the audible beep stops c) When the timer dial completes the rotation d) When the indicator light illuminates True/False 1. Electricity is defined as electrons in motion. 2. The metal housing of the tube head increases the safety of the x-ray machine. 3. Direct current flows in pulses and changes direction. 4. Voltage is the measurement of the number of electrons moving through a wire conductor. 5. If the tube head is properly sealed, the port is the only place through which x-rays can escape. 6. The x-ray beam formed at the focal spot is monochromatic. 7. The intensity of the beam refers to the quantity and quality of the x-rays. 8. The filament is on the negative side of the vacuum tube in the dental x-ray machine. 9. Dental x-ray machines may have controls for manual adjustment of kVp and mA, or these controls may be preset by the manufacturer. 10. In the ON position, the line switch on the control panel energizes the low- and high- voltage circuits. 11. Increasing the amperage will result in a production of more x-rays. 2112. That part of the cathode designed to direct the free electrons toward the tungsten target of the anode is called the “focal spot.” 13. The tungsten anode is embedded in a core of copper to conduct heat away to a radiator. 14. A small area on the tungsten target of the anode toward which the electron beam is directed is called the “focal spot.” 15. The step-down transformer corrects fluctuations in the current flowing through the x-ray machine. 16. The anode is the negative electrode (terminal) in the x-ray tube. 17. The collimator is a lead diaphragm that restricts the dimensions of the useful beam. 18. Thermionic emission refers to the release of electrons from the target material during the process of incandescence. 19. Primary beam refers to a high-energy, short wavelength x-ray beam. 20. An x-ray beam composed of many diferent wavelengths is called “polychromatic.” Short Answer 1. What does adjusting the kilovolt peak (kVp) do? 2. What is the name of the device that allows the amount of current passing through the wires of the circuit to be changed? 3. Why are the extension arm and yoke of the x-ray machine insulated? 4. What is the term for the measurement of the number of electrons moving through a wire conductor? 5. Inside the dental x-ray machine, what does the speed of the electrons determine? 6. Who is responsible for the radiation dose incurred by the patient during x-ray exposure? 7. What does kVp measure? 8. What is the purpose of a “deadman” exposure switch? 229. What is the term for the process by which electrons are created at the filament wire of the cathode? 10. In the cathode, the wire filament is recessed into what? Chapter 4 Multiple Choice 1. Which of these statements is FALSE? a) Structures should be magnified to enhance interpretation. b) An area of interest must be recorded completely with sufficient surrounding structures for a frame of reference. c) A radiograph should be of proper density, contrast, and definition. d) An image should be free of errors. 2. Each of the following is a term used to describe visual image characteristics EXCEPT one. Which one is the EXCEPTION? a) Sharpness b) Contrast c) Milliamperage d) Density 3. Which of these statements regarding radiographic contrast is FALSE? a) There are few shades of gray in a radiograph with short-scale contrast. b) Short-scale contrast describes a radiograph in which the density diferences between adjacent areas are large. c) There are many shades of gray in a radiograph with long-scale contrast. d) Long-scale contrast describes a radiograph in which the density diferences between adjacent areas are large. 234. The degree of overall blackness of a radiographic image is termed: a) sharpness. b) density. c) resolution. d) contrast. 5. The diference in densities between adjacent areas on the radiograph is termed: a) sharpness. b) density. c) resolution. d) contrast. 6. Which of these is NOT a shadow-casting principle? a) A large focal spot b) Long target–image receptor distance c) Short object–image receptor distance d) Parallel object–image receptor relationship 7. Which of the following statements about dental radiographic exposure variables is true? a) Increasing the mA darkens the radiograph. b) Decreasing exposure time darkens the radiograph. c) Exposure time is difficult to change on most machines. d) Milliamperage afects radiographic contrast. 8. An original radiograph is exposed at 8 mA for 1.0 seconds. If the mA is increased to 10, which of the following exposure times would be correct to maintain radiographic density? a) 0.4 b) 0.6 24c) 0.8 d) 1.0 40. Which of these statements is FALSE? a) Increasing the target–image receptor distance reduces penumbra. b) Radiation intensity is directly proportional to the square of the distance from the source. c) A long PID increases image sharpness. d) A recessed tube increases the target–image receptor distance. 41. Which of the following is recommended for increasing radiographic contrast while maintaining radiographic density? a) Increase kVp and increase exposure time. b) Decrease kVp and decrease exposure time. c) Increase kVp and decrease exposure time. d) Decrease kVp and increase exposure time. 42. Radiolucent images appear dark or black because: a) hard radiation was allowed to reach the image receptor. b) dense structures stopped x-rays from reaching the image receptor. c) soft radiation was stopped before reaching the image receptor. d) less dense structures permitted more x-rays to reach the image receptor. 43. Each of the following appear radiopaque EXCEPT one. Which one is the EXCEPTION? a) Bone b) Dentin c) Pulp d) Enamel 44. Which kVp setting produces long-scale image contrast? 25a) 65 kVp b) 75 kVp c) 85 kVp d) 95 kVp 45. Each of the following results in image unsharpness EXCEPT one. Which one is the EXCEPTION? a) Patient movement during exposure b) Image receptor positioned close to the teeth c) A short PID d) The use of intensifying screens 46. A radiographic film with a small crystal size 47. creates sharpness. 48. causes magnification. 49. decreases exposure time. 50. increases contrast. 51. Image magnification can be decreased by: 52. increasing the target-object distance. 53. increasing the object–image receptor distance. 54. decreasing the target-surface distance. 55. increasing the focal spot size. 56. When changing the PID length from 8 inches (20.5 cm) to 16 inches (41 cm), what corresponding change must be made to maintain image density? 57. Decrease exposure time. 58. Increase exposure time. 59. Decrease kilovoltage. 2660. Increase kilovoltage. 61. The inverse square law states that the intensity of the radiation: 62. increases as the distance from its source increases because the beam of radiation converges. 63. decreases as the distance away from its source increases because the beam of radiation diverges. 64. increases as the distance away from its source increases because the beam of radiation diverges. 65. decreases as the distance away from its source increases because the beam of radiation converges. 66. Which of the following refers to a radiographic image that is black and white with many shades of gray in between? 67. Low contrast 68. High contrast 69. Low density 70. High density 71. Which of the following indicates a radiographic image that is black and white with few shades of gray in between? 72. Short resolution 73. Long resolution 74. Short scale 75. Long scale True/False 1. White areas on a radiographic image are termed radiolucent. 2. Radiographic density (film darkening) is decreased when the milliamperage or exposure time is increased. 27