Ear Impression Taking
WHAT ARE EAR IMPRESSIONS?
Ear impressions are the “casts” taken individually from each person’s ear. The earmoulds for behind-the-ear (BTE) hearing aids and the custom-made hearing aids, including in-the-ear (ITE), in-the-canal (ITC) and completely-in-the-canal (CIC) hearing aids are derived from the ear impressions. Therefore, taking ear impressions is a very important step in the prescription of hearing aids. A good ear impression would ensure a hearing aid fits properly and comfortably in a person’s ear.
WHAT ARE THE STEPS OF TAKING EAR IMPRESSIONS?
Step 1: Getting medical clearance
Prior to taking ear impressions, a client would need to make sure he has no ear disease, infection and operation in the past 90 days. The client would also need to be certain that he has no itchiness, pus, wound, etc. in his ears at present. Clients with any symptoms mentioned above are not encouraged to proceed with ear impressions taking.
Step 2: Examination of the outer ear
An audiologist would examine the client’s outer ear, including pinna, ear canal and eardrum using an otoscope before he take ear impressions for the client. The audiologist would make sure there is no pus, infection or redness in the ear. In case of excessive or impacted earwax found in the client’s ear, the audiologist would refer the client for earwax cleaning. If any anomaly is found with the ear canal structure, the audiologist would also take extra care when taking ear impressions for the client.
Step 3: Taking ear impressions
i) Insert a cotton or foam block until the second bend of the ear canal.
ii) Mix one scoop of A material with one scoop of B material.
iii) Place the mixed impression materials inside a syringe.
iv) Insert the syringe inside the ear canal and then inject the material into the ear canal.
v) Fill the pinna with the material after the ear canal is filled up.
vi) Gently touch the material after a few minutes to check its hardness.
vii) Remove the material after 10 minutes or when it hardens.
viii) Re-inspect the ear with the otoscope to be certain that the ear is clear of the material.
x) These ear impressions will be sent to the lab for custom made ear moulds and hearing aids.
(Special thanks: We would like to thank 20dB Hearing’s audiologist and assistant for volunteering in the photo taking process. A heartfelt thanks to the audiologist, Elaine Yu, for wording this post.)