Intraoral radiography

Question 1

How do the voltage and the mAmps affect the number of X-rays?

Answer 1

kV affects penetration of X-rays

mAMPs affects the number of X-rays

Question 2

What percentage of electrons in an X-ray tube are converted to X-rays?

Answer 2

1% of electrons are converted into photons

Question 3

Good description of x-ray interaction with objects?

Answer 3

Objects are in the way of x-rays which means there is a shadow formed behind the object.

Question 4

What is the peri-apical radiography technique?

Answer 4

Peri-apical literally means beyond the apex of the tooth

Question 5

What are the things taht should be noted during image formation?

Answer 5

Crown of the tooth should be fully implemented

No distortion of the image should occur

Question 6

What is the parallel technique used for?

Answer 6

It allows us to obtain the best image possible.

Question 7

What is required for the parallel technique?

Answer 7

Parallel X-ray

Image receptor as close and parallel to the teeth

X-rays perpendicular aimed at image receptor

Question 8

How should orientation of the plate be different between incisors/canines and the molars/premolars?

Answer 8

Incisors and canines: Long axis of the detector should be placed vertically.

Molars and premolars: Long axis of the detector should be placed horizontally.

Question 9

Which plate size should be used for different teeth?

Answer 9

Incisors/canines: Size 1 plates

Molars/premolars: Size 2 plates

Question 10

What are the image detectors used in the dental school called?

Answer 10

PhotoStimulable Phosphor Storage Plates (PSPP)

Question 11

Why are PSPPs placed in a plastic envelope/barrier?

Answer 11

To avoid cross contamination

To avoid poisoning

To avoid light from erasing the latent image

Question 12

How can damage to PSPPs be avoided?

Answer 12

Use proper cleaning agents

Never bend a PSPP

Tell patients not to bite on the plate

A piece of cardboard inside the plastic envelope may be useful to avoid bitemarks

Question 13

How are image receptors held in the right place?

Answer 13

Using image receptor holding devices such as the Rinn set which uses a firm grip to hold image receptor and provides a good aiming aid for the X-ray machine to be positioned correctly.

Question 14

Why are bitewing radiographs taken?

Answer 14

They allow one to assess interproximal decay as well as interproximal bone height.

Question 15

How are bitewings modified to assess patients with severe periodontitis?

Answer 15

The image receptor is arranged vertically rather than horizontally.

This allows a better view and assessment of the actual vertical bone loss.

Patients with second permanent molars erupted require 2 bitewings from each side.

Question 16

How are bitewing images taken?

Answer 16

With parallel technique since this is the only way to aim perpendicular at the image receptor and through the contact points/interproximal surfaces.

Question 17

How should the orientation marker be oritentated for periapical radiographs?

Answer 17

Should be projected superior of the crown of the tooth. If one uses PSPP upside down, the marker will be projected on top of a root, apex or its vicinity.

Question 18

Where should the orientation marker be for bitewings?

Answer 18

Always in corner of image projected on or near a root.

Question 19

What is the orientation marker?

Answer 19

The little ‘a’ on PSPPs

Question 20

How should radiographs be looked at?

Answer 20

Mount radiographs as if you would look at the patient.