Earmold and Impression Techniques Flashcards

Silicone impression material is generally preferred over powder-and-liquid acrylic for ear impressions because silicone:

Answer: Is more dimensionally stable and flexible for easier removal

Silicone impression materials exhibit excellent dimensional stability after setting and their flexibility allows for easier, safer removal from the ear canal.

A patient complains that their new earmold causes a 'plugged up' or occlusion effect when chewing or speaking. The most appropriate first modification would be to:

Answer: Add or enlarge a vent in the earmold

The occlusion effect is caused by bone-conducted sound being trapped in a sealed ear canal, and adding or enlarging a vent allows this energy to escape.

When using a syringe to inject impression material, the nozzle should be positioned:

Answer: Touching the otoblock before slowly withdrawing as the canal fills

Starting at the otoblock and withdrawing as the material fills prevents air pockets from being trapped behind the material as it is injected.

Which earmold tubing size is most commonly used with a standard behind-the-ear hearing aid for adults?

Answer: #13 tubing

#13 tubing is the standard size used with most conventional BTE hearing aids and provides the appropriate acoustic bore diameter for typical amplification needs.

A 'skeleton' earmold differs from a 'semi-skeleton' earmold primarily in that the skeleton style:

Answer: Has material only in the helix and anti-helix area with an open concha bowl

A skeleton earmold has a rim of material following the helix and anti-helix contours but leaves the center of the concha bowl open, while a semi-skeleton retains part of the bowl.

Before taking an ear impression, otoscopic examination is performed to:

Answer: Assess the health of the ear canal and determine safe otoblock placement depth

Otoscopy allows the clinician to inspect the ear canal for cerumen, inflammation, perforation, or other contraindications to impression taking, and to gauge safe otoblock depth.

Which condition would be an absolute contraindication to taking an ear impression without physician clearance?

Answer: A suspected perforated tympanic membrane

A perforated tympanic membrane means impression material could enter the middle ear space, making physician evaluation and clearance mandatory before proceeding.