Earmold Impressions

Question 1

Does the valley of the ear become a helix lock for retention?

Answer 1

Yes

Question 2

What is the valley?

Answer 2

The area right behind the crus

Question 3

Does the crus align with tube orientation?

Answer 3

Yes

Question 4

Does the concha bowl provide stability and/or retention?

Answer 4

Yes

Question 5

Does the antitragus provide retention?

Answer 5

Yes
It keeps the earmold from coming out

Question 6

Where is the isthmus?

Answer 6

Before the 2nd bend
About 10 mm into the canal

Question 7

Where does cartilage change to bone in the ear canal?

Answer 7

At and past the 2nd bend

Question 8

Is the isthmus placement consistent in all people?

Answer 8

Yes

Question 9

How far do we want to go past the 2nd bend?

Answer 9

2 mm

Question 10

Why do we want to go 2 mm past the 2nd bend?

Answer 10

For retention

Question 11

What is aperture?

Answer 11

Acoustic seal area

Question 12

Do we need to stretch the aperture to create the proper fit?

Answer 12

Yes
A loose hearing aid is actually more uncomfortable

Question 13

Do you choose what kind of impression material to use based on how much you want to stretch the aperture?

Answer 13

Yes
Some stretch it more than others

Question 14

What are the three kinds of impression material?

Answer 14

Addition-cured silicone
Condensation-cured silicone
Methyl-methacrylate

Question 15

What is addition-cured silicone?

Answer 15

Combines 1:1 polyvinyl-siloxane parts of paste
This is the one we use in class

Question 16

What is condensation-cured silicone?

Answer 16

Dimmethyl-siloxane paste mixed with hardener
Not as commonly used

Question 17

What is methyl-methacrylate?

Answer 17

Powder and liquid
Pre-measured acrylic powder and liquid formulas are rapidly mixed together
Mainly used when someone has silicone allergies

Question 18

What is viscosity?

Answer 18

Refers to how easily material flows before it cures

Question 19

What is high viscosity?

Answer 19

Thick
Resistant to flow
Condensation-cured silicone
Stretches the aperture of the canal

Question 20

What is medium viscosity?

Answer 20

Provides some stretch to aperture
Addition-cured or methyl-methacrylate

Question 21

What is low viscosity?

Answer 21

Runny and loose
Flows easily
Will not alter the anatomical structure of the ear canal
Most suitable for devices requiring deep insertion
Addition-cured silicone
Doesn’t stretch the aperture very much

Question 22

Is aperture stretching important for attenuation products and deep in canal impressions?

Answer 22

No

Question 23

What is stress relaxation?

Answer 23

Materials ability to return to its shape after removal

Question 24

What material is superior for stress relaxation?

Answer 24

Silicone
Methyl-methacrylate’s shape can distort during removal (low stress relaxation)

Question 25

What is contraction ratio?

Answer 25

It refers to shrinkage over a 7-day period

Question 26

How much will silicone shrink (contraction ratio)?

Answer 26

0.1-0.7%

Question 27

How much will methyl-methacrylate shrink (contraction ratio)?

Answer 27

3%

Question 28

What is shore value?

Answer 28

It refers to the after-cure hardness Lower shore values are likely to be damages during the shipping process

Question 29

What is the shore value of silicone?

Answer 29

High

Question 30

What is the shore value of methyl-methacrylate?

Answer 30

Low and is susceptible to heat Requires being glued to box for shipping

Question 31

What are the mandatory case history questions before earmold impressions?

Answer 31

Immunocompromised or diabetes? Blood thinners? History of ear surgery? Allergies to silicone or nut oils?

Question 32

Should you sit down while performing otoscopy?

Answer 32

Yes

Question 33

What should you visualize during otoscopy?

Answer 33

Pinna, TM, and anterior canal wall

Question 34

Why do you want to visualize the anterior canal wall?

Answer 34

It will help us guide down the otoblock

Question 35

Should you pay attention to the vagus nerve activity?

Answer 35

Yes, it may impact impression taking May make them cough or gag

Question 36

Should you identify any congenital malformations or surgical signs during otoscopy?

Answer 36

Yes, could be a widening after the 2nd bend

Question 37

Should you document any pre-impression abnormalities in the medical record?

Answer 37

Yes

Question 38

What are some of the things you should document in the medical record?

Answer 38

Cerumen Active infection Prolapsed canal (exostoses and osteoma) Collapsing canal Significant jaw movement Things that require precautions (perf, malformation, thick hair growth)

Question 39

Should you note the ear canal direction during otoscopy?

Answer 39

Yes Awareness of the variety shapes, textures, and sizes increases efficiency and safety

Question 40

Should you pull up and back (down for peds) on the pinna during otoblock insertion?

Answer 40

Yes

Question 41

Should you pull up and back (down for peds) on the pinna during the ear mold impression?

Answer 41

No

Question 42

What are the three types of canal blocks?

Answer 42

Foam otoblock, cotton block, and pressure release block

Question 43

What is a pressure release block?

Answer 43

It has a clear tube in it that is open at one end It allows air between the otoblock and the TM to release through the tube

Question 44

What are some benefits of a cotton block?

Answer 44

Provides more information on the anatomy of the ear canal Easier to modify It is easier to confirm block immovability

Question 45

Is foam more abrasive than cotton?

Answer 45

Yes

Question 46

How big should a foam block be?

Answer 46

Just bigger than the ear canal opening

Question 47

How big should a cotton block be?

Answer 47

The same size as the opening

Question 48

What extra precaution should you take if you have a patient with a perf?

Answer 48

Ensure there are no gaps between the block and the canal wall

Question 49

What should you be cautious of with a patient with PE tubes?

Answer 49

Aggressive block depth may cause pain

Question 50

What should you be cautious of with a patient with a widening canal/mastoidectomy?

Answer 50

May require more than one block

Question 51

What is a sign of a widening canal?

Answer 51

If insertion beyond isthmus becomes easier

Question 52

How do you confirm block placement?

Answer 52

Removal string is at the center of the canal Visualize anterior canal bend (2nd bend placement) Apply slight pressure to feel bone on anterior canal wall (2nd bend placement) Check for gaps Should not move with slight pressure

Question 53

Do open jaw impressions increase the size of the aperture for a snugger fit?

Answer 53

Yes Condyle of the mandible moves forward and pulls on the anterior canal wall

Question 54

How should you place the block in the mouth for a single impression?

Answer 54

Place in mouth horizontally on the side of the impression

Question 55

How should you place the block in the mouth for a double impression?

Answer 55

Place vertically in the center of the mouth

Question 56

What are some benefits of a spleen pad?

Answer 56

Maintains temperature Reduces risk of health hazard to audiologists following repeated absorption of chemicals into the skin Reduces risk of contaminating material

Question 57

Should you wear medical gloves when hand mixing?

Answer 57

No

Question 58

How should you dispense the impression material?

Answer 58

Keep the tip embedded in the material so it will flow in an outward direction

Question 59

What should you do with the syringe after dispensing the material?

Answer 59

Remove the hardened silicone Wipe down with disinfectant

Question 60

What is a precaution you should always take when taking impressions?

Answer 60

Hold the string

Question 61

Should you fill the canal slowly?

Answer 61

Yes To avoid the otoblock moving deeper

Question 62

What is the last step of impression making?

Answer 62

Use a level marking

Question 63

How should you remove the impression?

Answer 63

Wiggle it to release pressure seal Remove from under antihelix and twist forward

Question 64

When should you do otoscopy?

Answer 64

Before and after impressions

Question 65

What should you do if someone is bleeding after an impression?

Answer 65

Apply pressure to wound for 10 minutes Use a large cotton otoblock soaked in a vasoconstrictor (afrin) Recheck heath of ear one week later

Question 66

What are some rules to check is an impression is good?

Answer 66

Are there concentric circles? Is the valley filled? Is the concha cymba filled? Is the concha cavum filled?