May be a silly Q but why do hearing aids have molds? whats the diff bewteen this vs open molds vs just an in ear headphone piece?


#1

Okay, I dont understand, I mentioned on another thread of mine, im new, just getting to grips with them, but I cannot seem to fathom the difrence between full molds, open molds and just what you would call “in ear” headphones, they all put put sound right into our ear right?

I have actually seen people with “in ear” headphone type vs molds and I just wonder whats the differences/benefits a mold actually gives?

The right ear mold to my hearing aids are just painful, have had it sanded down a few times, still pain, but in ear headphones are not painful for me at all… I cannot see any benefits a mold would give.


#2

I have profound hearing loss and require a very powerful bte hearing aid. I have used hard shell, soft shell earmolds. Soft earmolds stick to the ear better and cause no feedback noise. Open and closed domes do not work well with powerful bte hearing aids.l have tried in the ear headphones and it will wear out quickly due to strong amplification. A hearing aid has a heavy duty receiver and sound is transmitted to the ear mold by tubing. There are receiver in ear hearing aids that have larger receivers in earmold. If your right earmold is still painful then you need to try a softer earmold with less depth to your right ear canal.


#3

I wear in the ear hearing aids and really like them. For me they have been less trouble and I normally put it them in my ears when I get up and forget them.


#4

Not a silly question! Generally, we try to fit patients as “open” as possible. Sometimes this means using non-custom open domes, or using a large vent in an earmold. This allows low-frequency sound through, i.e. deep, bass sounds. We can do this so long as a patient has normal low-frequency hearing. If not, we use closed non-custom domes or earmolds with small or no vents so that the hearing aid can provide that low-frequency information without leaking out of the ear.


#5

Custom ear molds are also needed if there are issues adjusting the hearing aids without getting troublesome feedback between the microphones and speakers because they are so close together. With custom molds the microphones cannot pick up as much sound from the speakers…

For hearing aids, the speakers are generally referred to as receivers.


#6

I wear closed custom molds. The main reason is to prevent low frequencies with high volume (aka noise) to reach the ear directly. With open fittings the hearing aid has to amplify high frequencies much more than neccessary for closed fittings so that I could understand anything in loud noise (eg. driving car, train in underground). The side-effect is that music via bluetooth sounds much better.


#7

Thanks for all your replies everyone, I’m still having trouble somewhat with mine.
See thread “Bass frequencies help for Music”


#8

Since no replies, maybe make it that I can hear clearer with inear headphones vs on ear/overear and my question was why have molds? That was the general gist of my OP question…

I hear better over Xbox Live, taking my hearing aids out, and talking to people with IN EAR headphones than having over ear headphones with my hearing aids in… just leads me to (and I’ve seen them) why have ear molded hearing aids if I can hear better with direct in ear headphones… why have molded hearing aids at all if direct in ears make me hear best?


#9

Everyone is different I use my hearing aids as my headphones now. There was a time I used over the ear headphones with my hearing aids so could understand podcasts and audiobooks. But as hearing aids technology has improved I can now use my hearing aids as my headphones and enjoy my music and podcasts and audiobooks.


#10

Not sure what you mean by hear “best.” It’s common for in ear headphones to sound better because they have bigger speakers and provide more bass. Custom molds are used to create a good seal so that more gain in higher frequencies can be applied without generating feedback. Some of these higher frequencies can be helpful in making speech understandable. So for understanding speech, I’d think you could do better with hearing aids. Music on the other hand is in the ear of the beholder and whatever works for you is great.


#11

Since I’ve never hear above 8KHz What I mean is, I can clearly hear people talk with in ear headphones if i take my hearing aids out to place them in, but with over ears and hearing aids, its still garbled - although I do suffer recruitment hearing loss so it isnt as simple as just making sounds louder for me. BUT having said that, an in ear headphone I can talk to most people on Xbox Live or the PSN Network - I shouldnt be able to do this, but I can, however with hearing aids IN and a headphones the fit around it, perform worse, and I then cannot tell what they are saying. With in ear ones, I can - thus my question, why have molds?


#12

As explained, molds (as opposed to domes) are custom fit to create a better seal. If off the shelf domes work for you, than no need for custom molds.


#13

Oh and alright then, why do some people get those whats called “hidden” aids that sit IN EAR, these have no molds, what benefit do these even have? Jeeze!


#14

The in Ear aids are custom molded. The hearing aids are just contained in the molds.


#15

OK Crazy? You are NOT! Believe me, we’ve all lumped through the very same questions and issues you are experiencing now. In the 35 years I’ve worn aids, I’ve transitioned from ITE to full shell to ITE again, and now RIE as of the past couple years.

Some semantics here: ITE = In The Ear, hard plastic mold, flesh colored, fits in ear; full shell = hard plastic, flesh colored, fills most of the ear cup; RIE = Receiver In the Ear, can have either an open, closed, mound or in my case double silicone power dome for the best (tightest) fit in the ear canal.

The type of mold or dome a person gets on the aids is largely a function of their hearing loss, altho dexterity, vanity and other issues can also be factors. For me, ideally, I’d be wearing a BTE (Behind The Ear) unit connected by plastic tube to the receiver in my ear, but I am hideously allergic to that clear plastic mold that fills the ear cup. I’m lucky that the double dome does the job, but I find that matchstick-sized receiver HURTS when it’s seated nice and deep in my ears.

I no longer get molded plastic aids either, cuz with age, I’m finding that my ear canals swell and recess during the day - the mold would simply never fit optimally at any given minute of the day.

If your molds are STILL painful, DO go in and have them re-cast! It irks me that audis will sometimes blow this off (maybe they don’t want to pay $100 to send in the new impressions?). It’s critical that an aid feels like you’re not even wearing them - and also delivers excellent sound quality with NO squeaky-leakage.

Hope that helps! Persevere: after all YOU’re the one wearing them!


#16

I use custom molds with a single vent (small hole drilled through the acrylic mold). When I was trialing aids with domes, I had a lot of feedback issues (I could not bring my hand or any object close to my ear without aids squealing). The molds eliminated almost all feedback. They are not as comfortable as domes and I have to reposition the molds in my ears several times a day, but it is worth it to 1) be able to hear and understand what people are saying and 2) not worry about feedback squealing anymore


#17

OK: try this link, as it shows pictures and has a brief explanation of the different styles of hearing aids. Altho, even this page does not have the “in ear” headphones you refer to. You are right in that they ALL put sound right into our ear, BUT - and this is key! - different levels of hearing loss need BIGGER and more SNUG FITTING aids to get the best sound quality.

Again: RUN to your audi and have that uncomfortable aid re-cast! Geez! You should not have the case sanded down - it weakens the structure. Believe me, I’ve gone that route, and my aid was sanded down so much that the case became transparent in one spot.

By the same token, do NOT accept any mold that requires nail polish or some other toxic material to bulk UP the size for a better fit. Nope. That will lead you down the path to irritation, rash, and NO aids as your ears heal. Been there, done that, too.


#18

Looking for a recent “molds” discussion to add my $0.02.

Got fitted for silicone select-a-vent molds earlier this week and am awaiting finished product. My audi used the ReSound SYRINGE method of mold impression making and I found the following ReSound course on Audiology Online that discusses and ILLUSTRATES the mold impression making process in detail. The procedure is more complicated than just having an In-The-Canal mold in the end, since I take it the ReSound procedure can be used to manufacture a complete custom hearing aid to be inserted fully into the ear within the space taken by the impression. The niceties in getting a proper impression are discussed in detail (unfortunately, the 2015 presentation is in Adobe Flash so you’d have to have a setup that supports that if you want to watch the animations and the videos).

I learned one important (very rare?) risk from the video that my audi did not advise me about (informed consent in audiology?!). If the audi screws up and does not do a good job of placing the foam block in the ear canal to block access of the mold impression material to the tympanic membrane, the mold material can set glued to the tympanic membrane and a careless audi, when the impression is pulled out, can remove all or part of your tympanic membrane causing you permanent hearing loss.

The other end result that my audi showed me after taking my impressions is that my left ear has a very narrow canal until the canal reaches the vicinity of my ear drum, where it really flares out. That means that I’ll probably get a large mold for that ear that I’m going to have a bit of a time getting inserted through my narrow canal. But the impression, recreating the 3D structure of my ear canal, really illustrated why I have had a hard time finding the size power dome that I want to occlude my ear canal as much as I want - there is so much variability in the size of the canal along its route to my ear drum.

Looking forward to getting my finished molds and hoping it’s not a struggle to use them, esp. for the left ear.

https://www.audiologyonline.com/E/25843/384908/4450167f37ad55febc

P.S. the other thing my audi didn’t discuss was the impression technique left a lot of oily “stuff” in each ear canal. After the procedure, I just reinserted my HA’s and was shocked later to see how wet the domes and receivers looked the next time I pulled them out. Over the next few days the “wetness” has gone away. Perhaps it was some by-product of the polymerization process (low molecular weight silicone material that got left out of the polymerization process?). I’ll have to ask the audi the next time I see her.


What Did Your Provider Say When You Told Him/Her That Your'e a DIY'er?
#19

This is kind of an old post, but I think the simple answer to your question is feedback. A hearing aid has a microphone and speaker system. If the speaker output leaks back to the microphone input it causes feedback. The reason to have a dome or mold is to isolate the speaker from the microphone input to prevent feedback at higher gains. If you use basic earbuds from recorded music or other electronic source, there are no microphones involved, so no possible feedback, and higher gains can be used.


#20

Rare, yes. Impression taking and wax removal are really the most dangerous things that we do. And yes, audiologists in my experience don’t do a great job of laying out fully informed consent. Though, doctors/nurses do not either as I’ve never heard of a patient going to the doctor for wax removal and being told in advance that there is a non-zero risk that they will blow right through the eardrum with the big silver syringe. I see a lot of fall-out from doctor-office wax removals, from just infection through to ossicular damage and permanent hearing loss. I have happily never had an incident with taking impressions, though I’m sure in a long career many clinicians will have at least one nerve-wracking moment. We all hear horror stories circulated that may or may not be apocryphal, but mostly the worst is that the impression material gets stuck because of some blind corner and the patient has to see an ENT for removal with some pain but no permanent damage. I don’t know anyone directly who has ever seen significant trauma from an impression.

But to give you an idea of the rarity of real damage: Doctors pay thousands of dollars in insurance every year agaist medical mishaps. I pay only dozens of dollars per year.