Couplers Flashcards
What material is recommended for a rigid pinna?
Soft material
What material is recommended for a soft/floppy pinna?
Hard material
What are some things we need to consider when fitting a pediatric patient?
Hygiene, activities, insertion, and growth
How often will kids up to the age of 4 get a new earmold?
Every 3 months
What is chosen as a last resort for its hypoallergenic properties?
Polyethylene
What is soft vinyl used for?
Infants
Firm ear texture
High gain devices
What is hard vinyl used for?
Older adults with dexterity issues
Facial flex problems (requires tight seal of aperture)
What are some disadvantages of vinyl?
Shrinks, hardens, and discolors quickly
Polishing requires toxic solvent with 24 hr drying time
What does vinyl feel like?
Soft but not grippy
What is silicone typically used for?
Pediatric
High gain devices
Allergies
Facial flex problems
What does silicone feel like?
Soft and grippy
What are some disadvantages of silicone?
Grippy material can cause blisters or increased discomfort
Difficult to modify
Tubing cannot be glued (requires tube locks)
Costs slightly more
What is platinum cure silicone?
Most popular type
Hardness varies from Shore A 25 to Shore A 60
Glossy or matte
Known for longevity
Modification requires special tools
What is heat cure silicone?
Better choice when high precision is needed for intricate details (power BTE hearing aids)
Provides a superior seal
What is lucite commonly used for?
Adults
Mild to severe loss
Floppy pinna
What are some disadvantages of lucite?
Will not compress to move beyond narrow areas
Increased risk of feedback with movement (creates gaps)
Potential risk of injury if hit
What is a combination mold?
Hard material on the outside for the concha
Use soft, semi-soft, or pliable materials for the canal
Provides a stronger seal
What are some reasons for selecting a style?
Retention
Aperture seal
Cosmetics
Vent size needs
Is output dependent on the acoustic seal?
Yes
Can jaw movement impact the acoustic seal?
Yes
What decisions can the movement of the canal impact?
Material
Anti-tragus or cymba concha retention points
Are most custom molds equal in their fitting ranges?
Yes
What is the primary purpose of a full shell mold?
Max retention and acoustic seal
High output for severe to profound losses
What is the purpose of a skeleton mold?
Maximizes retention and acoustic seal
Offers comfort as the concha bowl remains exposed to air
Decreases moisture accumulation
Inconspicuous
Mild to severe losses
Why would a semi-skeleton be used?
For insertion ease
Is deep insertion (2 mm beyond second bend) required for smaller customs?
Yes
What is the purpose of a canal mold?
Cosmetic
Lowest degree of acoustic seal
What is the purpose of a canal lock?
Cosmetic with retention lock
Improved retention
What is the purpose of a half shell?
Ease of insertion
Retention
Fills half of concha
Can canal, canal lock, and half shell molds all accommodate mild to severe losses if they go beyond the 2nd bend?
Yes
When should an open dome be used?
High frequency loss with normal hearing up to 1500 Hz
When should a closed or tulip dome be used?
Mid freq amplification
Requires hearing thresholds better than 40 dB HL below 1 kHz
When should a power dome be used?
Some amplification in mid to lows
Requires thresholds to be better than 40 dB HL below 1 kHz
