Lec 5 Object Localization

Question 1

What are the 3 approaches to decipher three-dimensional relationships by radiography?

Answer 1

(1) Examine two conventional images projected at right angles to each other.

(2) Use the tube-shift technique employing conventional periapical views.

(3) Image the anatomic region with a three-dimensional imaging modality.

Question 2

Examine two images projected at __________ to each other

Answer 2

right angles

Question 3

Use ____________ employing conventional periapical views.

Answer 3

tubeshift technique

Question 4

Other terms for tubeshift technique (2)?

Answer 4

• buccal-object rule
• Clark’s rule

Question 5

It is the manner in which, the relative positions of radiographic images of two separate objects change when the projection angle at which the images were made is changed.

Answer 5

Tube-shift technique

Question 6

When an object lies ______ to the reference object, its image appears to move in the direction of the tube shift.

Answer 6

lingual

Question 7

When the object lies _____ to the reference object, its image appears to move in the direction of opposite to the tube shift.

Answer 7

buccal

Question 8

SLOB is an acronym for?

Answer 8

Same Lingual, Opposite Buccal

Question 9

SLOB technique is used for which structures? (5)

Answer 9

• Mental foramen
• Incisive foramen
• Impacted teeth
• Foreign objects
• Multiple pulp canals

Question 10

These are images that project a three-dimensional volume onto a two-dimensional receptor and may produce an eggshell effect of corticated structures.

Answer 10

Plain radiographs

Question 11

Tangential path of photons

Answer 11

Eggshell effect

Question 12

Eggshell effect are seen in:
- normal structures such as? (3)
- abnormal structures such as (1)?

Answer 12

Normal:
- lamina dura
- border of the maxillary sinuses
- nasal fossa

Abnormal:
- corticated walls of cysts and benign tumors