test one Flashcards
When were X-rays discovered
1895
What is the approximate vertical angulation for bitewing radiographs?
+10 degrees
A radiograph is defined as
A picture on film produced by the passage of sprays through an object or body
An error in which of the following would result in overlapping
horizontal angulation
Who discovered the x-ray
Wilhelm Conrad Roentgen
Radiation is defined as
a form of energy carried by waves or streams of particles
Otto Walkhoff took the first radiograph on a patient T or F
False
While taking radiographic projections the patients head should be resting on headrest with the chin pointing towards the ceiling T or F
False
What is the purpose of BWX
To see maxillary, mandible and adjacent tooth surfaces
What are the types of BWX
horizontal and vertical
What are the 6 important concepts to remember
- Receptor placement
- Receptor position
- Vertical angulation
- Horizontal angulation
- PID position
- Receptor exposure
What is the receptor position for BWX
parallel to teeth you want to capture
What is the Horizontal angulation for BWX
(side to side) PID & PSP parallel
What is an example of a patient protection technique used before x-ray exposure
proper prescribing of radiographs
The main suggestion for the operator’s protection is that the operator must
Avoid the primary beam
The acronym for the permitted lifetime accumulated dose is
MAD-Maximum accumulated dose
Inherent filtration in the dental x-ray tubehead
Includes filtration that takes place when the primary beam passes through the glass tubehead seal
A circular collimator (diaphragm) produces a round beam that is ___Inches in diameter
2.75
The ALARA concept states that all radiation must be kepth
As Low As Reasonably Achievable
A film badge
is worn by the operator
____- speed film is currently the fastest intraoral film available
F
The single most important factor in patient protection is the inherent filtration of the X-ray tube head
FALSE
What does the collimator do
restricts the size and shape of primary beam
What is filtration
the use of absorbing materials for removing low energy x-rays from primary beam
What is inherent filtration
Glass window of X-ray tube head, insulating oil and tube head seal (lead glass or aluminum)
What is added filtration
aluminum disks added between collimator and the tube head seal
What is the filtration for a machine operation at or below 70 KVP
1.5 mm aluminum
What is the filtration for a machine operating at or above 70 KVP
2.5 mm aluminum
What after exposure technique will protect patient and operator
proper film/sensor handling and proper film processing/sensor retrieval
a small(short) object-receptor distance will increase magnification of the tooth image T or F
False
a periapical film must show
the crown to the apex of the tooth
According to the basic principles of the paralleling technique, the film is placed in the mouth ____ to the long axis of the tooth being radiographed, and the central ray of the x-ray beam is directed ____ to the film and long axis of the tooth.
Parallel; perpendicular
Elongation is caused by too much vertical angulation
False
In taking a periodical radiograph using the bisecting technique, the x-ray beam was not centered on the film packet. The resulting film shows
Cone cut
When using the Parallel technique the film and the ___ should be as parallel as possible
Long axis of the tooth
When using the bisecting technique what is the relationship between the imaginary bisector and the central ray
the central ray is perpendicular to the imaginary bisector
What factor affects forshortening and elongation of a tooth image on the film while using the bisecting technique
vertical angle
In taking a periodical radiograph using the bisecting technique, the x-ray beam was not centered on the film packet. The resulting film shows
Cone cut
When the bisecting technique is used, which of the following angles is bisected
the angle formed by the receptor and the long axis of the tooth
One of the advantages of the bisecting technique is
they can be used when a patient has a shallow palate
Who was responsible for using the paralleling technique in practical dental radiography
McCormack
Who developed the first x-ray tube
Coolidge 1913
Who introduced the bisecting technique
Price
Who wrote the first paper on the danger of x-radiation
Rollins 1896
Who exposed the first dental radiograph in the US using a skull?
Morton 1896
Who introduced the long-cone paralleling technique
Fitzgerald 1947
Who wrote the first dental text; introduced bite-wing technique
Raper 1925
Who exposed the first dental radiograph in the United States on a living patient?
Kells 1896
Who exposed the first dental radiograph
Walkoff 1896
What is a cathode ray
A stream of high-speed electrons that originates from the cathode in an x-ray tube
What is fluorescence
A glow that results when a fluorescent substance is struck by light, cathode ray, or x-rays
What is radiation
A form of energy carried by waves or a stream of particles
What is x-radiation
a high-energy radiation produced by the collision of a beam of electrons with a metal target in an x-ray tube
What is the purpose of radiation guidlines?
to protect the patients and ourselves to minimize the amount of radiation both parties are exposed to
What is an angle
A figure formed by two lines diverging from a common point
What is angulation
The alignment of the central ray of the x-ray beam in both planes
What is horizontal angulation?
The positioning of the pid in a side to side plane
What is vertical angulation
The positioning of the PID in an up and down plane
What is the difference between a horizontal and vertical bitewing
The position of the bitewing receptor; with the long portion of the receptor horizontal or vertical
What is crystal bone
The most coronal portion o the alveolar bone found between teeth; it composed of cortical bone and appears radiopaque
What are areas where teeth are no longer present called
endentulous
What is the bisecting technique
A method used to expose pariapical images
When does elongation occur
When the vertical angle is too flat
When does foreshortening occur
When the vertical angle is too extreme
What is the occlusal projection
An intra oral radiographic examination used to examine the buccal and lingual aspects of the mandible and locate foreign bodies
What is a topographic occlusal projection used for
to examine maxillary and mandibular anterior teeth
What is interpretation
The explanation of what is viewed on a dental radiograph
What is the primary beam
the penetrating x-ray beam produced at the target within the x-ray head
No federal standard existed for dental x-ray machines manufactured before what year?
1974
When were x-rays first used in dentistry?
1895
When x-rays were first used in dentistry, how long was the exposure?
25 min
Dental films placed inside the mouth are termed
Intraoral Films
The component part of the dental x-ray machine that contains the x-ray tube is termed the?
tube head
The component part of the dental x-ray machine that allows movement and positioning of the tube head is termed the?
extension arm
The dental radiographer can regulate the x- ray beam (kilovoltage, mA, time) through the use of the:
Control panel
A device that is used to stabilize an intraoral film is:
Film holder
A metal instrument that is used to restrict the size of the -ray beam to the size of the Intraoral film is the?
Collimator device
What does the term bitewing refer to
A patient biting on a wing or a tab
What is the purpose of a bitewing
To detect caries and see in between teeth
What size of film is recommended for the use with the bitewing technique in an adult patient?
Size 2
What does bisect mean
to divide into two equal parts
What are the advantages of the bisecting technique?
Easier placement for patients (more comfortable),
No anatomical restrictions
Name some disadvantages of the bisecting technique
More distortion
Harder to place x-ray beam
ln the bisecting technique the central ray is directed?
Perpendicular to the imaginary bisector
With the bisecting technique the vertical angulation is determined by the _____.
imaginary bisector
What are the common types of intraoral film?
1) Bitewing (Interproximal examination)
2) Periapical film
3) Occlusal
Which film is used to examine the entire tooth and supporting bone?
periapical film
Name advantages to the parallel technique.
Accurate Image
Easy to replicate beam angle from appointment to appointment
Easier to determine where the beam should be
How do you achieve parallelism?
Film must be placed away from the tooth and toward the middle of tiie oral cavity
The 8 inch PID is more effective in reducing radiation exposure to the patient than the 16 inch PID.
False
What is the most effective PID in reducing patient exposure?
Rectangular PID
What is used as a collimator?
lead plate
What is the recommended size of the beam at the patients face?
2.75 inches
