L5 Intra and Extraoral Scan

Question 1

digitalization

Answer 1

the conversion of text, pixtures, or sound into a digital form that can be processed by a computer

Question 2

digitalization

Answer 2

the conversion of text, pictures, or sound into a digital form that can be processed by a computer

Question 3

digital dental impression

Answer 3

the conversion of 3D image data of oral and other structures into a digital format that can be processed by a computer

Question 4

STL (meaning)

Answer 4

steriolithography

Question 5

STL (definition)

Question 6

STL stands for

Answer 6

steriolithography

Question 7

STL (definition)

Answer 7

standard tesselation language or standard

Question 8

STL stands for

Answer 8

steriolithography

standard tesselation language

Question 9

STL files

Answer 9

-accepted by most CAD/CAm software
-no information on colors
-no information on internal structures

Question 10

image capture made by

Answer 10

light projection and capture

Question 11

reconstruction of 3D data

Answer 11

matching poitns of interest taken uner different angles

Question 12

what type of light is captured by the scanner

Answer 12

diffuse light

Question 13

d

Question 14

diffuse reflection

Answer 14

the reflection of light from a surface such that incident ray is reflected at many angles, rather than at just one angle

Question 15

what is detected to reconstruct 3D data?

Answer 15

detection of transition areas, such as strong curvatures, physical limits, or difference of gray intensity

Question 16

what is created to evaluate similarity between images?

Answer 16

transformation matrix

Question 17

resolution (definition)

Answer 17

number of points per mm squared

Question 18

does resolution affect the accuracy of scan?

Answer 18

no

Question 19

what affects the accuracy of scan?

Answer 19

software advancement

Question 20

depth of view

Answer 20

distance between scanner tip and object needed to capture an image

Question 21

is it better to have a fixed or range depth of view?

Answer 21

better to have RANGE

Question 22

speed of scanner

Answer 22

faster = more convenient

Question 23

are smaller or larger scanners good for capturing hard areas?

Answer 23

smaller

Question 24

closed system scanners

Answer 24

-sends scan to one of a few software programs for designing or milling

Question 25

main advantage of closed system scanner

Answer 25

straightforward flow

Question 26

main disadvantage of closed system scanner

Answer 26

limited

Question 27

example of closed system scanner

Answer 27

PrimeScan (CEREC)

Question 28

open system scanner

Answer 28

sends scans to all other open system software programs for design for milling

Question 29

main advantage of open system scanner

Answer 29

versatile

Question 30

main disadvantage of opens ystem scanner

Answer 30

complex workflow

Question 31

main disadvantage of opens system scanner

Answer 31

complex workflow

Question 32

examples of closed system scanners

Answer 32

Trios 4 (3Shape) emerald (planmeca)

Question 33

caries detection by scanner

Answer 33

same / not better than visual detection potential against histological detection!

Question 34

shade matching by scanner

Answer 34

not there yet! digital intraoral scanner may not be used as an accurate method of shade selection (must confirm with visual verification)

Question 35

2 factors that can affect your scan

Answer 35

isolation retraction and placement of margin

Question 36

isolation and scanner

Answer 36

saliva or blood in the scan will appear as hard tissue scanning in a dry field is a must!

Question 37

retraction and placement of margin and scanner

Answer 37

you must be able to clearly visualize your margin so that the scanner can capture it the scanner does not see what you can't see!

Question 38

scanning errors

Answer 38

1. contaminated field / unexposed margins 2. missing data 3. double scan

Question 39

extraoral scanning

Answer 39

-light capture -reconstruction of 3D data (matching of points of interest taken under different angles)

Question 40

what is different about extraoral scanning

Answer 40

-capture area -moisture control (not an issue) -double scan (not a problem)

Question 41

is there a difference in accuracy of extraoral vs intraoral scanning?

Answer 41

no

Question 42

benefits of intraoral scanning

Answer 42

-saves time -supra or equigingival margins -hard and attached soft tissue -severe undercuts

Question 43

benefits of extraoral scanning

Answer 43

-saves cost -subgingival margins -boarder molding (complete denture)