Chapter 13: The Periapical Examination- Paralleling Technique

d

Which of the following statements is false?

A) A sterile cotton roll may be placed on the opposite side of the biteblock for stabilization of the image receptor holder.

B) The external indicator ring attachment must be as close to the patient's skin as possible without touching.

C) The patient must bite down on the biteblock firmly enough to hold the image receptor in place.

D) The biteblock backplate must be at a 105-degree angle for use with the paralleling technique.

a

Excessive vertical angulation when using the paralleling technique results in

A) cutting off incisal/occlusal edges.

B) cutting off the apices.

C) foreshortened images of the teeth.

D) elongated images of the teeth.

a

Which image receptor placement is most likely to be more comfortable and allow the patient to become accustomed to the procedure?

A) Maxillary anteriors

B) Maxillary posteriors

C) Mandibular posteriors

D) Posterior bitewings

d

When using the paralleling technique, the patient must bite down on the image receptor holder biteblock as far away from the teeth as possible with the exception of which area?

A) Maxillary anteriors

B) Mandibular canines

C) Maxillary premolars

D) Mandibular molars

c

Which of the following is a basic principle of the paralleling technique?

A) The image receptor is placed perpendicular to the long axes of the teeth.

B) The central ray of the x-ray beam is directed parallel to both the teeth and the recording plane of the image receptor.

C) The image receptor is placed parallel to the long axes of the teeth.

D) The central ray of the x-ray beam is directed perpendicular to an imaginary bisector.

c

The principles of the paralleling technique include each of the following except one. Which one is the exception?

A) The image receptor is placed parallel to the long axis of the tooth of interest.

B) The central ray of the x-ray beam is directed perpendicular to the tooth and to the image receptor.

C) The central ray of the x-ray beam is directed at a plane halfway between the long axis of the tooth and the long axis of the image receptor.

D) Parallel placement of the image receptor is accomplished using an image receptor holder.

b

Which of these statements is false?

A) The paralleling technique does not meet all five shadow-casting principles in all regions of the oral cavity on all patients.

B) With the paralleling technique, it is not possible to direct the central rays of the x-ray beam to both the tooth and the image receptor simultaneously.

C) The paralleling technique is the technique of choice for obtaining periapical radiographs.

D) With the paralleling technique, the object and image receptor are positioned parallel to each other.

c

Each of the following statements regarding the principles of the paralleling technique is correct except one. Which one is the exception?

A) Parallel placement of the image receptor is accomplished using an image receptor holder.

B) The central ray of the x-ray beam is directed perpendicular to both the teeth and the image receptor.

C) The patient is directed to hold the image receptor in the mouth with a finger or thumb.

D) The image receptor is placed parallel to the long axes of the teeth of interest.

b

Comparing the paralleling technique with the bisecting technique, which of the following statements is correct?

A) The paralleling technique is easy to achieve on all patients.

B) Proficiency should be achieved in both techniques.

C) The bisecting technique is more likely to be uncomfortable for the patient.

D) Once the full mouth series procedure is started, the radiographer must continue with the bisecting or the paralleling technique and not mix the two.

a

The paralleling technique must achieve parallelism by placing the image receptor

A) away from the crowns of the teeth.

B) away from the root tips of the teeth.

C) closer to the crowns of the teeth.

D) closer to the root tips of the teeth.

b

To compensate for the increased object-image receptor distance needed to achieve parallelism

A) the target-image receptor distance should be decreased.

B) the target-image receptor distance should also be increased.

C) the object-image receptor distance should also be increased.

D) the object-image receptor distance should be decreased.

c

What is the ideal target-image receptor distance used with the paralleling technique?

A) 8 inches (20.5 cm)

B) 12 inches (30 cm)

C) 16 inches (41 cm)

a

Which of the following is not an advantage of the paralleling technique?

A) It is ideal for positioning radiographs for children.

B) It minimizes superimposition of adjacent structures.

C) It produces images with minimal dimensional distortion.

D) With appropriate image receptor-holding devices, it takes less time than trying to locate the position of an imaginary bisector

c

Which of the following is not a disadvantage of the paralleling technique?

A) The best images are obtained with the more difficult to position long (16 inch) PID.

B) Image receptor positioning is difficult for patients with small mouths.

C) There is a limited number of image receptor holders that accommodate the paralleling technique.

D) It is more likely to excite an exaggerated gag reflex to achieve parallel position in the posterior region.

a

Anterior periapical radiographs should be positioned in the oral cavity with the long dimension ________, and posterior periapical radiographs should be positioned in the oral cavity with the long dimension ________.

A) vertical, horizontal

B) horizontal, vertical

C) horizontal, horizontal

D) vertical, vertical

d

Which teeth should be imaged on an adult molar periapical radiograph?

A) Distal half of canine, first premolar, second premolar, and first molar

B) Distal half of first premolar, second premolar, first molar, and second molar

C) Distal half of second premolar, first molar, second molar, and third molar

D) Distal half of first molar, second molar, and third molar

b

What is the ideal design of a paralleling image receptor holder?

A) A short bite block and an L-shaped backing

B) A long bite block and an L-shaped backing

C) A short bite block and a 105-degree backing

D) A long bite block and a 105-degree backing

c

Image receptor positioning devices are available for use with the paralleling and bisecting techniques because slight modifications may be implemented.

A) The first part of the statement is true. The second part of the statement is false.

B) The first part of the statement is false. The second part of the statement is true.

C) Both parts of the statement are true.

D) Both parts of the statement are false.

d

The patient must bite down on the biteblock as far away from the teeth as possible, using the full extent of the biteblock to maintain a parallel relationship between the image receptor and the teeth in all regions of the oral cavity except the

A) maxillary incisors and canines.

B) mandibular incisors and canines.

C) maxillary premolars and the maxillary molars.

D) mandibular premolars and the mandibular molars.

a

Centering the image receptor to line up behind the central and lateral incisors to include recording the mesial halves of the canines if using a size 2 image receptor describes the placement of the image receptor for which periapical radiograph?

A) Central incisor

B) Canine

C) Premolar

D) Molar

a

With the paralleling technique, the central ray is directed perpendicular to the long axes of the teeth and the plane of the image receptor

a. True

b. False

b

When using the paralleling technique, insufficient vertical angulation will result in loss of the image of the crowns.

a. True

b. False

a

The paralleling technique is preferred over the bisecting technique.

a. True

b. False

a

The paralleling technique does not meet the shadow-casting principle that requires placement of the image receptor close to the teeth of interest.

a. True

b. False

b

To compensate for the increased object-image receptor distance needed to achieve parallelism, the target-surface receptor distance should be increased.

a. True

b. False

b

The use of the paralleling technique is ideal for adult patients with a small mouth or shallow palatal vault.

a. True

b. False

a

An advantage of the paralleling technique is that it produces accurate radiographic images with a minimal amount of superimposition of adjacent structures.

a. True

b. False

b

Image receptor holders designed for use with the paralleling technique usually have a short biteblock.

a. True

b. False

a

Universal image receptor positioners can accommodate a range of digital sensor sizes.

a. True

b. False

a

An image receptor holder with an external aiming device can make radiographic errors less likely.

a. True

b. False

a

When using an image receptor holder with an external aiming device, the patient's head does not need to be precisely positioned

a. True

b. False

b

An image receptor holder with an external aiming device is more comfortable for the patient.

a. True

b. False

b

In the paralleling technique, the distance between the tooth and the image receptor is usually closer than ideal.

a. True

b. False

b

If an image receptor holder has an external aiming device, then the patient must be seated upright with the head straight.

a. True

b. False

b

Because of the supporting structures on the maxillary arch, to accomplish a parallel relationship between the image receptor and the long axes of teeth, the image receptor must be placed closer to the teeth.

a. True

b. False

b

Image receptors with an external aiming device eliminate radiographic technique errors.

a. True

b. False

a

Correct vertical angulation is determined by positioning the central rays perpendicular to the long axis of the teeth of interest.

a. True

b. False

b

A patient may bite down on a sterilized cotton roll that is placed on the same side of the biteblock as the teeth to provide stabilization and add to patient comfort.

a. True

b. False

a

If using an image receptor holder with an external aiming device, the indicator ring attachment must be slid all the way down the metal arm of the device to be as close to the patient's skin as possible without touching the patient prior to the exposure.

a. True

b. False

a

Correct horizontal angulation is determined by positioning the image receptor parallel to the embrasure of two predetermined teeth.

a. True

b. False