Radiology (T5)

Weak radiation leaving the tube during exposure is prevented by use of a/an:

Aluminum Filter

Which option below, best describes an ion?

An atom that has lost electrons

Disadvantages of the bisecting technique include:

Angulation problems and image distortion

When exposing periapical radiographs with the bisecting technique, always begin with the:

Anterior teeth

What does ALARA stand for?

As Low As Reasonably Achievable

Digital imaging systems can be used for which images?

Bite-wing Panoramic Cephalometric ALL OF THE ABOVE

Which of the following is the most radiosensitive?

Bone Marrow

When looking at amount of radiation needed for digital vs film x-ray, how do they differ?

Digital requires less radiation than film to produce an image

What is the negatively charged particle that is responsible for producing dental radiographs?

Electron

Which of the following appears most radiopaque on an image?

Enamel

Foreshortening of the maxillary radiographic image results from:

Excessive Vertical Angulation

All extraoral and intraoral radiographs can be taken with the same type of x-ray unit.

False

Radiation leaks are always detectable by either taste or smell.

False

The advantages of the bisecting technique outweigh the disadvantages.

False

The thyroid gland is more radiosensitive than small lymphocytes.

False

All x-ray machines made after 1974 must abide by ______ guidelines that regulate performance standards.

Federal

What is the speed of electrons through a circuit referred to as?

Kilovoltage

What is the term for a pattern of stored energy on the exposed film that cannot be visibly seen?

Latent Image

What component of the X-ray tubehead restricts the size of the X-ray beam?

Lead Collimator

Which of the following mandibular landmarks can be seen on a panoramic image but CANNOT be seen on intraoral images?

Mandibular Condyle

When taking an image of the maxillary molars, you are going to see which of the following landmarks?

Maxillary Sinus

A small, round radiolucency between apicies of the mandibular premolars:

Mental Foramen

The amount of electrons needed to produce a diagnostic film is referred to as:

Milliamperes

The cathode in the ________________ terminal.

Negative

Critical organs that can be damaged by dental radiography include all of the following except:

Oral Mucosa

When the contact area of a tooth is superimposed over the contact area of the adjacent tooth on a radiograph:

Overlapping

The styloid process is visible on which type(s) of images?

Panoramic Radiograph

In the bite-wing technique, the receptor is placed __________ to the crowns of both the maxillary and mandibular teeth.

Parallel

Primary Radiation is:

Penetrating beam that is produced at the target of the anode

The beam of radiation which is responsible for exposing the x-ray film is the:

Primary

Character Radiation is:

Produced when a high-speed electron dislodges an inner shell of a tungsten atom

General Radiation is:

Produced when an electron hits the nucleus of a tungsten atom

When looking at a film, which tooth structure is radiolucent?

Pulp

On a panoramic image, the lip-line appears:

Radiolucent where the lips do not cover the teeth and radiopaque where the lips cover the teeth

Sensors that cannot be sterilized

Require complete coverage with disposable plastic sleeves for each patient

The function of the collimator used in the panoramic x-ray machine is to ____________________.

Restrict the size and shape of the x-ray beam

The bisecting technique is based on the:

Rule of isometry

Effects seen in the individual that has been irradiated:

Somatic Effects

Advantages of panoramic imaging include which of the following?

The entire maxilla and mandible are seen on one image It is easy and quick to learn how to expose a panoramic image Patients prefer panoramic images and are exposed to less radiation ALL OF THE ABOVE

The panoramic image is the preferred image for the detection of caries and periodontal disease. The panoramic image is preferred for the evaluation of eruption patterns, growth, and development.

The first statement is false; the second statement is true

Your patient has asked why you prefer digital imaging to film. Which of the following reasons would you tell her?

The image appears almost instantaneously for both of us to view

In the bisecting technique, the receptor is placed perpendicular to:

The long axis of the tooth

Scatter Radiation is:

The result of an x-ray being deflected from its path

The J- or U-shaped radiopacity located superior to the maxillary first molars:

Zygomatic process of maxilla

To avoid a lead apron artifact on a panoramic radiograph

use a lead apron without a thyroid collar, and place the lead apron low around the neck of the patient so that it does not block the x-ray beam

Which describes the proper direction of the central ray in the bisecting technique?

90 degrees to the imaginary bisector

The speed of electrons through a circuit is referred to as:

Kilovoltage

Due to the slight bend in the vertical angulation during the bite-wing technique, what angle is used to compensate?

+10

Which of the following is the recommended angulation for properly capturing a periapical film of the mandibular premolars?

-10 to -15

When converted from the SI system to the Traditional system, one Gray is equivalent to how many rads?

100

According the the inverse square law, when the PID is changed from 16 inches to 8 inches, the resultant beam will be ____ times as intense

4

An occlusal receptor (size ____) may be used for some extraoral images.

4

What is the maximum permissible dose annually?

5 REMS

Extraoral images may be used in conjunction with intraoral images. Extraoral images are not as defined or sharp as intraoral images.

Both statements are true

The term used to describe the softer, matrix of spongy bone in-between 2 layers of dense bone is:

Cancellous Bone

The side of the patient's head is positioned adjacent to the receptor for what type of x-ray

Cephalometric

An "exaggerated smile line" is seen on the dental image if the patient's

Chin is tipped down

A "reverse smile line" is seen on the image if the patient's

Chin is tipped up

Secondary Radiation is:

Created when the primary beam interacts with matter

Radiation injuries that are not seen in the person irradiated but that occur in future generations are termed:

Genetic Effects

Each panoramic unit has a(n) ______ that is used to align the patient's teeth as accurately as possible.

Head positioner

A dental image that demonstrates very dark areas and very light areas is said to have:

High contrast

Exposure time is measured in _____ because x-rays are created in bursts rather than a continuous stream.

Impulses

What is the bite-wing technique used to examine?

Interproximal surfaces, detecting decay, and bone levels

Dental receptors placed inside the mouth are termed:

Intraoral

The term given to the intersection of the nasal cavity and the maxillary sinus is:

Inverted Y

Radiation is considered harmful because it:

Is cumulative

What exposure factor controls the quality of the x-ray beam?

KVp

Because biologic damage results from x-ray exposure, dental images should be prescribed for a patient only when the benefit of disease detection outweighs the risk of biologic damage.

True

Besides gamma rays, what additional radiation wave from the EMR spectrum is considered harmful to tissue due to its wavelength?

Ultra-Violet

Which of the following is an indication for the bisecting technique:

When the patient states that it is too painful to bite down, when the patient has a shallow palate, when rubber dam is placed ALL ARE INDICATIONS

After removing an exposed film from the patient's mouth, the first thing you should do is:

Wipe saliva from film

A beam of energy that has power to penetrate objects and record their shadows is an/a ___________.

X-ray

Which beam alignment device includes bite blocks, aiming rings, and indicator arms?

XCP