CBCT

Question 1

T/F: CBCT images the area in a slice by slice fashion.

Answer 1

False

Images as a volume

Question 2

T/F: CBCT uses an area detector.

Answer 2

True

Question 3

T/F: Several rotations are needed to get a CBCT image.

Answer 3

False

One rotation

Question 4

T/F: Routine CBCT imaging is the standard of care.

Answer 4

False

Only when will aid in diagnosis based on clinical exam

Question 5

What are the limitations of CBCT?

Answer 5

Image noise and poor soft tissue contrast

Question 6

T/F: CBCT has a submillimeter resolution.

Answer 6

True

Question 7

What is the advantage to image-intensifier detectors?

Answer 7

Compatible with bridging to other softwares (CAD/CAM)

Question 8

What are some disadvantages to image-intensifier detectors?

Answer 8

Larger, more sensitive to distortion, more calibration needed, earlier need for replacement

Question 9

The ________ is the part of the detector used to amplify the electrical signal from the x-ray attenuation.

Answer 9

scintillator

Question 10

_________ is defined as the ability to subtle changes in grayscale and distinguish from background noise.

Answer 10

Contrast resolution

*ability to see different densities

Question 11

________ is defined as the ability of an imaging system to record separate structures positioned close to each other.

Answer 11

Spatial resolution

Question 12

T/F: All metal including RPDs should be removed prior to CBCT imaging.

Answer 12

True

Question 13

T/F: The largest field of view possible should be used when taking CBCT image.

Answer 13

False

Smallest FOV that will see what you need to see

Question 14

What is typically included in a medium FOV scan?

Answer 14

Typically both arches

Question 15

What determines the spatial resolution?

Answer 15

Voxel size

Question 16

T/F: To achieve a sharper image, reduce the object-to-detector distance and increase the source-to-object distance.

Answer 16

True

Question 17

T/F: Smaller voxel size will equal a higher spatial resolution.

Answer 17

True

Question 18

What would be the result of a higher number of projections?

Answer 18

1. Higher spatial resolution
2. Greater contrast resolution
3. Increased radiation dose

Question 19

T/F: A 180 degree scan mode is adequate for implant treatment planning.

Answer 19

True

Want 360 for pulp canals

Question 20

_________ are seen in CBCT when sharp changes in density are present.

Answer 20

Streak artifacts

Question 21

What is a beam hardening artifact?

Answer 21

Center is very dark with bright edges

Question 22

What is a starburst artifact?

Answer 22

Object sends streaks into nearby tissues

Question 23

T/F: CBCT is much better for detecting proximal caries.

Answer 23

False

Question 24

T/F: CBCT is much better at detecting perio disease.

Answer 24

False

Maybe bone craters and furcations

Question 25

T/F: There is benefits for routine CBCT imaging in orthodontics.

Answer 25

False

Question 26

T/F: CBCT is a good tool for analyzing airway obstruction.

Answer 26

True

Question 27

T/F: The dentist is only responsible for reading the teeth in a CBCT scan.

Answer 27

False

Responsible for everything in the scan