Radiographic Technique Flashcards
The distance of the x-ray machine head from the patient should be what?
Kept as short as possible
What are the results when kVp is low?
Low density
High contrast
What are the results when kVp is high?
High density with very little contrast
Where should the radiographic film be placed?
So that the plastic side is facing toward the subject and head of the radiographic unit
When is the parallel technique for oral radiographs indicated?
To evaluate the caudal mandibular teeth and the nasal cavity
Where is the x-ray film packet or sensor inserted to capture the posterior mandible (mandibular premolar and molar teeth)
Between the tongue and mandible
Where can the parallel technique not be used?
The rostral and caudal maxilla (the hard & soft palates are in the way)
The rostral mandible (the mandible prevents putting the film parallel to the teeth)
What can be used instead in areas where the parallel technique cannot be used?
The bisecting angle technique
How is the bisecting angle obtained?
By visualizing an imaginary line that bisects the angle formed by the x-ray film and the structure being radiographed
What happens to the image if the x-ray beam is aimed at the tooth?
The image will be distorted by elongation
What happens to the image if the x-ray beam is aimed at the film?
The image will be foreshortened
How do you take an x-ray using the bisecting-angle technique?
The x-ray head is positioned so that the beam of the x-ray will be perpendicular to the imaginary bisecting-angle line
Where is the film placed to capture the maxillary caudal teeth?
Across the maxilla parallel to the hard palate
Equal margins on both sides of the maxilla
The long end of the film is parallel with the muzzle
Where is the machine head placed to capture the maxillary caudal teeth?
45 degrees off the vertical and horizontal planes of the muzzle
Where is the film placed to capture the maxillary rostral teeth?
Parallel to the hard palate
Where is the machine head placed to capture the maxillary rostral teeth?
45 degrees off the vertical and horizontal planes of the patient’s muzzle
Where is the film placed to capture the mandibular anterior teeth?
Parallel to the mandible
Where is the machine head placed to capture the mandibular anterior teeth?
70 degrees off the horizontal plane of the anterior mandible with the patient in dorsal recumbency
What are the least views used to obtain a complete radiographic study?
6 views Right and left posterior maxilla Right and left posterior mandible Anterior maxilla Anterior mandible
How are the canine teeth best evaluated?
By placing the machine head 45 degrees from the front of the patient and 45 degrees from the side of the patient
Where should the dimple of the film be?
“In the air” on the right side
“In the bone” on the left
How many roots does the maxillary 4th premolar have?
3
What rule describes what to do when the mesiobuccal and palatal roots are lining up together?
The SLOB rule
Same lingual, opposite buccal
The thickness of the sensor makes it difficult to get it back far enough in the mouth to reach the maxillary second molar. What is the solution to this?
Move the sensor as far back as possible, then move the machine head further caudal and aim it more rostral
Due to the thickness of the sensor and the musculature and angle of the jaw, it is difficult to reach the mandibular third molar. What is the solution to this?
Move the machine head further caudal and aim it more rostral
Due to the location of the maxillary canine, what is the best bisecting angle to capture this tooth?
Angled midway between the front and side of the muzzle and midway from the plane of the tooth and plane of the sensor
What are the two techniques to help visualize the roots of the third and fourth premolar of cats?
The extraoral technique
The almost parallel technique
Where is the sensor, the patient and the head of the machine placed for the extraoral technique?
The sensor is placed directly on the tabletop
The patient’s head is placed on the sensor
The x-ray beam is directed so that it skylines the palate
Where are the film and head of the machine placed for the almost parallel technique?
The film is on the opposite side of the mouth being studied
The beam is directed to that it skylines the palate
