Dental Radiography Principles and Practices, Exams of Advanced Education

Download Dental Radiography Principles and Practices and more Exams Advanced Education in PDF only on Docsity! National Boards Dental Hygiene Exam 2024 A film radiograph turns yellow-brown over a period of 5 months. What is the most likely explanation? Light leak in the dark room Film was used past its expiration date Inadequate washing of the film Film was excessively fixed - ANSWER-Inadequate washing of the film Excessively fixed= turns light Past expiration=looks fogged/light Light leak in dark room= turns dark/black A maxillary molar PA may show all of the following anatomical landmarks except one. Which one is the exception? Maxillary tuberosity Maxillary sinus Zygomatic Process Inverted Y - ANSWER-Inverted Y A wall of bone that separates the nasal fossa from the maxillary sinus. It is seen above the maxillary canines A periapical radiograph is exposed with a phospher plate. After exposure, the student opens up the packet in the clinic and leaves the plate under the white light. How will the radiograph appear after it is scanned? Light Dark Fogged Blurry - ANSWER-Light A periapical radiograph is intended to be exposed with a vertical angulation of +20 degree. The operator inaccurately uses a vertical angulation of +55 degree. What problem will occur? Foreshortening Overlapping Magnification Unsharpness Elongation - ANSWER-Foreshortening A radiograph is a three-dimensional representation of a three-dimensional object produced on an image receptor True False - ANSWER-False A radiograph is a TWO-dimensional representation of a three-dimensional object produced on an image receptor A radiograph is found to be too light. Which of the following could explain this problem? Developer temperature too high Exposure time too long Light leak in the dark room Exposure time too short - ANSWER-Exposure time too short All the others will cause film to be too dark According to the inverse square law, as the distance between the tungsten target and film is increased, the: Useful beam is less safe for the patient Useful beam has greater intensity resulting a darker film Useful beam is less intense Useful beam is decreased in size - ANSWER-Useful beam is less intense All of the following are examples of principles that contribute to an ideal radiographic image except one. Which one is the exception? • Small source of radiation • Long target-to-object distance • Long film-to-object distance • Object parallel to the film • Central ray perpendicular to the film - ANSWER-Long film-to-object distance All of the following characteristics of the darkroom safelight are correct except one. Which one is the exception? At least 4 ft between the light and the film Red filter safe for intraoral films No more than 15 watts light bulb Orange filter for extraoral films - ANSWER-Orange filter for extraoral films "" for Intraoral NOT extraoral The first statement is false, the second statement is true Both statements are true The first statement is true, the second statement is false Both statements are false - ANSWER-Both statements are false Distortion of images within a dental radiograph taken using the bisecting technique occurs primarily due to: -An incorrect exposure time -Incorrect placement of the film holder -The central ray not being perpendicular to the tooth and film -An excessive negative vertical angulation - ANSWER--The central ray not being perpendicular to the tooth and film E2 dental caries usually appears on the proximal tooth surfaces as a radiolucent triangle with the base at the _____ and the point at the ____. CEJ...Enamel surface DEJ...CEJ Enamel surface...DEJ DEJ...enamel surface - ANSWER-Enamel surface...DEJ Electromagnetic radiation is the transmission of energy thru space and matter. It is generated when the velocity of electrically charged particles is altered. The first statement is false, the second statement is true Both statements are true The first statement is true, the second statement is false Both statements are false - ANSWER-Both statements are true Factors that influence magnification of film images include all of the following except one. Which one is the exception? Focal spot size Target-fim distance Film speed Object-film distance - ANSWER-Film speed Film fog is caused by: High developer temperature Outdated films Light All of the above - ANSWER-All of the above How much added filtration is required for an x-ray unit that operates at 80 kVp? 1.0 mm Al 2.0 mm Al 1.5 mm Al 2.5 mm Al - ANSWER-2.5 mm Al Required for all units operating over 70 kVp. Units under should have 1.5 mm Al If the patient's head is too far backward (away from the sensor) in a pano, how will the teeth appear on the radiograph? Too wide Too narrow Too short Too long - ANSWER-Too wide Magnification of an image can be reduced with which of the following? Larger object-image distance Larger focal spot Longer source-image distance Shorter PID - ANSWER-Longer source-image distance Most of the crystals on a dental x-ray film are made up of which compound? Silver bromide Silver sulfide Potassium bromide Silver iodide - ANSWER-Silver bromide Make of 95% of crystals Pano's are useful for all of the following except one. Which one is the exception? Detection of large lesions Evaluation of of impacted teeth Evaluation of alveolar bone loss Evaluation of tooth eruption - ANSWER-Evaluation of alveolar bone loss Schedule I drugs have the least amount of abuse potential. Schedule V are drugs with no accepted medical use with extremely high abuse potential such as herion. The first statement is false, the second statement is true Both statements are true The first statement is true, the second statement is false Both statements are false - ANSWER-Both statements are false Schedule I = most abuse potential Schedule V= least abuse potential Static electricity appears radiographically as: Black lines White areas/sparks Scratched emulsion Film fog - ANSWER-Black lines The dentist wants to evaluate the floor of the mouth for presence of a sialolith. He should expose a mandibular occlusal radiograph using a vertical angulation of Anterior...-90 degrees Cross sectional...-90 degrees Anterior...-65 degrees Cross-sectional...-65 degrees - ANSWER-Cross sectional...-90 degrees CS are used for localization of objects in buccal, lingual, and to visualize floor of the mouth The following is an example of which type of radiation? Penetrating x-ray beams produced at tungsten target. Primary Secondary Scatter - ANSWER-Primary The following is an example of which type of radiation? Energy lost by deceleration/braking of high-speed electron. Bremsstrahlung Secondary Scatter - ANSWER-Bremsstrahlung The following is an example of which type of radiation? Form of secondary radiation that has been deflected from its path by interaction with matter (hard and soft tissues) Primary Scatter Bremsstrahlung - ANSWER-Scatter Ionized Shell Compton - ANSWER-Compton When taking a pano, the _____ must be perpendicular with the floor Maxilla Midsagittal plane Ala-tragus line Frankfort plane - ANSWER-Midsagittal plane When the process of ionization occurs within the x-ray tube head: Tungsten atoms lose and electron The filament is cooled Tungsten atoms remain neutral The focusing cup absorbs electrons - ANSWER-Tungsten atoms lose and electron When using the bisecting angle technique for PA's: - The film is placed at an angle with one edge touching the tooth - The central ray is directed perpendicular to the tooth and film - An increased target-receptor distance is required - The film is placed away from the tooth - ANSWER-- The film is placed at an angle with one edge touching the tooth Which division of the autonomic nervous system is responsible for increased heart rate, capillary constriction, dilation of bronchioles, decreased secretions Parasympathetic nervous system Sympathetic nervous system - ANSWER-Sympathetic nervous system Which extraoral projection depicts the soft tissue profile of the patient's face? Posterior-anterior skull Reverse Towne Lateral Oblique Lateral cephlomatic - ANSWER-Lateral cephlomatic Which of the following apical inflammatory lesions appear radiopaque? Periapical cyst Periapical granuloma Acute apical periodontitis Condensing osetetitis - ANSWER-Condensing osetetitis Which of the following are true regarding the latent image? It is formed after exposure, but before processing It results from the film placement in fixer before developer It can be seen with the eye as a light image It occurs late in the sequence of processing and developing - ANSWER-It is formed after exposure, but before processing Which of the following is NOT true regarding x-rays? Consist of particles with mass equal to an electron Can cause ionization of atoms Travel at the speed of light Can cause cancer in some tissues - ANSWER-Consist of particles with mass equal to an electron X-rays are weightless bundles of energy Which of the following is true regarding brehmmstrahlung x-rays? They have a single energy level They make up most of the x-rays produced Both are true Neither are true - ANSWER-They make up most of the x-rays produced aka "braking radiation" Which of the following is true regarding dental caries? Caries produces a radiolucent image Proximal caries usually arises apical to the contact point Caries on the root surface is called cervical burnout - ANSWER-Caries produces a radiolucent image Proximal caries usually arises apical to the contact point Cervical burnout is an optical illusion when the eye must distinguish between very light area and dark on the radiograph Which of the following is true regarding dental x-ray film? Exposure to white light will darken the radiograph It has emulsion on one side of the base Most crystals are silver iodide D-speed film is the fastest speed group - ANSWER-Exposure to white light will darken the radiograph Which of the following is true regarding ghost images on a pano? -Appear more blurred than the true image -The ghost image has the same general shape as its real counterpart -Appear at a lower level than the true image -Appear on the same side as the true image - ANSWER-The ghost image has the same general shape as its real counterpart Which of the following settings controls the energy (quality) of x-rays? Added filtration and millamperage Millamperage and exposure time Exposure time and Kilovoltage Kilovoltage and added filtration - ANSWER-Kilovoltage and added filtration ^kVp=more energy/strength of beam + filtration absorbs low energy photons( absorbs by tissue leading to biologic damage) Which of the following steps are different in the bisecting angle technique compared to the paralleling technique for PA's? Horizontal angulation, vertical angulation, and receptor placement Horizontal angulation and receptor placement Vertical angulation and horizontal angulation Receptor placement and vertical angulation - ANSWER-Receptor placement and vertical angulation Which of the following will reduce the patient's radiation dose during dental radiograph procedures? 12 inch instead of a 8 inch PID Circular instead of a rectangular PID F-speed instead of a D-speed film - ANSWER-F-speed instead of a D-speed film 12 inch instead of a 8 inch PID Which of the following would appear radioluscent on a radiograph? Anterior nasal spine Mental ridge Genial Tubercles Maxillary sinus - ANSWER-Maxillary sinus Which of the following would appear radiopaque on a radiograph? Incisive foramen Mylohyoid ridge