MEDICINE
RADIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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all exposure time is significantly longer
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image distortion is less likely
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image distortion is more likely
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the amount of radiation absorbed by the patient is increased
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Detailed explanation-1: -Disadvantages to the bisecting technique include image distortion, and excess radiation due to increased angulations exposing the eyes and thyroid. Paralleling technique provides less image distortion, and reduces excess radiation to the patient.
Detailed explanation-2: -A method of taking a periapical radiograph such that the x-ray tube is placed at 90° to a line bisecting the angle between the long axis of the tooth and the periapical film. The method is designed to reduce distortion of the radiographic image.
Detailed explanation-3: -Magnified distortion is influenced by the distance of the object to be radiographed from the film, and the distance of the focal spot of the tube from the film.
Detailed explanation-4: -The major disadvantages of the paralleling technique are difficulty in placement of the receptor, relative discomfort to the patient caused by the receptor holding devices. In order to achieve parallelism, the receptor must be placed away from the tooth.