Ear molds are one of the most fundamental parts of a traditional, behind-the-ear (BTE) hearing aid. The first main component of a BTE is the hearing aid itself, which includes the microphones and the electrical components as well as the battery. This portion comes in a variety of sizes depending on the power required based on the degree of hearing loss.

The second main component of a BTE hearing aid is the ear mold. Your audiologist will have taken an impression of your ear for a custom ear mold, which may come in a variety of materials such as silicone (soft) or acrylic (hard) and may fill your entire concha or just a portion. A soft tube will connect the earmold to the hearing aid itself, and this tubing (and possibly the earmold) will be replaced regularly. 

hearing aid ear molds
Image Credit: Widex

This article will provide an overview of the process of getting a custom ear mold, their functionality in hearing aid use, the different types of ear molds and how the material and shape are selected, as well as the appropriate care and maintenance of an ear mold. 

Understanding ear molds in hearing aid fittings

Every ear is uniquely shaped and sized with different nooks and grooves. An ear mold is custom-made for each individual ear. This involves the audiologist or hearing aid dispenser putting a small cotton or foam block in your ear canal, followed by soft impression material. It takes a few minutes to cure, and then it is removed and sent to the manufacturer for the custom devices to be made. The impression needs to go relatively deep into the ear canal so that the manufacturer can determine how best to orient the opening.

The ear mold is the bridge between the hearing aid and the ear canal, and it is critical for sound quality for the sound to be directed at the ear drum. Some ear canals are straighter or curvier than others, so by providing a deeper impression, the technology can determine the best position for the opening as well as any venting requested. If the impression isn’t deep enough, it’s possible the sound could be directed straight into the wall of the ear canal, which would lead to poor sound quality. 

It is normal for the process of having an ear mold impression taken to feel a bit uncomfortable. Rest assured that it only takes a couple of minutes, so any discomfort will be temporary. There is a brand-new technology available to some providers that allows the professional to create a 3D scan of the ear without using any physical impression material at all. This may be especially appealing for patients who struggle with the earmold impression process or need to have them made regularly, such is the case with pediatric patients.

What are ear molds made of? 

There are three main materials used in the manufacturing of ear molds: silicone, vinyl, and acrylic (sometimes referred to as lucite). Silicone is a soft, slightly flexible material, whereas acrylic is hard and solid. Vinyl is somewhere in between on the spectrum; it is not quite as soft as silicone or as hard as acrylic.

There are different reasons why a provider would recommend one material over the other. Soft silicone ear molds tend to provide a better seal on the ear and, therefore, are commonly recommended for patients with severe to profound hearing loss in order to maximize the amount of amplified sound that remains in the ear canal. They are also recommended for children, in part because of their growing ears and because of the greater likelihood that a child may fall or hit their head, which would be considerably more painful with a hard ear mold in their ear.

Here are some testimonials from patients who have used soft ear molds made of silicone material and are pleased with them:

The most annoying thing about hearing aids is the screeching – such as when you hug someone, or a jet flies overhead, or when your ear gets close to anything. This solved that problem perfectly because it really forms to your ear, and no more squealing!

Sharolin

I have been using this one for over a year, and have found it to be ultra-comfortable, great sound and very good quality. It is very soft silicon and has lasted far longer than any other piece I have used.

Brian

So comfortable, and sound is perfect.

Amy

Acrylic ear molds are the most durable; they will not shrink, break down, or harden over time. They are very easy to clean and may be more comfortable for some patients. Additionally, they are often recommended for new hearing aid users as they are easier to insert than soft ear molds. Acrylic ear molds are more prone to feedback (the whistling sound occasionally heard from hearing aids) because they do not form as tight of a seal and will not move with the jaw while chewing or talking. Acrylic is available in all kinds of colors and patterns, with glitter and glow-in-the-dark options for patients who want to make a statement with their ear molds or hearing aids.

These are some testimonials from patients who have used hard acrylic or lucite ear molds and liked them:

My ear molds are so easy to insert and, once they are in, I barely notice them throughout my workday.

Lucille

I have had my acrylic molds for over a year and they are as good as new. Really easy to wipe down at the end of the day with a cloth to remove any wax. I love how low maintenance they are.

Richard

After a few days with my new ear molds, the left one was bothering me. I took it back to my audiologist’s office and she was able to shave it down in about two minutes and the issue was totally resolved.hout my workday.

Barbara

Vinyl is somewhere in between and, therefore, is not typically recommended as a first choice for ear mold material but is used when one of the other two is not optimal. Perhaps a patient tries an acrylic mold and finds it easy to insert but is uncomfortable with jaw movement; an audiologist might recommend trying vinyl before moving to silicone.

Vinyl is not usually recommended for patients who have any allergy concerns, and it is not available in all of the bright multicolored or glitter options. Additionally, it is susceptible to shrinking, hardening, and becoming discolored over time. Another disadvantage to vinyl ear molds is that the tubing needs to be glued in place, which can be cumbersome for the audiologist or hearing aid dispenser.

hearing aid ear molds
Image Credit: www.audiologyonline.com

All of these materials are able to be modified by the audiologist or hearing aid dispenser if needed. 

What are the shapes of ear molds?

Now that we have reviewed the choices of materials for ear molds, we will cover the shapes and styles. We will start with the largest mold and work our way through the more open-fit and smaller styles.

hearing aid ear molds
Image Credit: Oticon
  1. Full-shell molds. “Full-shell” refers to the mold filling the concha bowl. This type of ear mold is recommended for severe to profound hearing losses to ensure the tightest possible seal and keep all the sound in the ear canal. It is also recommended for children due to the retention. Some patients may opt against a full-shell mold for aesthetic reasons, as it is very visible, while others may prefer a larger canvas to express themselves with different colors and patterns on their ear molds!
  2. Half-shell molds. As the name implies, this type of ear mold would fill about half of the concha bowl. It may be more aesthetically pleasing for some patients but maintains most of the benefits of a full-shell mold in terms of the seal and ease of insertion.
  3. Skeleton molds. A skeleton mold holds the shape of the ear with the outer edge, but the inside of the mold is open. This style appeals to many patients because the ear feels a bit less occluded, so it can be more comfortable while still maintaining good retention. While skeleton molds can be made in hard or soft materials, they are more often recommended in acrylic. The retention and durability of this style with the thin edge is better in acrylic than silicone.
  4. Canal molds. These earmolds fit into the ear canal without extending into the concha bowl. These are obviously a more discrete option which appeals to many patients, though retention can be an issue. In these cases, a “canal lock” mold can be used, which has a sort of tail that extends into the bottom of the concha bowl and helps to keep the earmold in place while still remaining relatively invisible.
  5. Micro molds. The most commonly dispensed type of hearing aids today is receiver-in-canal (RIC) or receiver-in-the-ear (RITE), which sit behind the ear but with the receiver (speaker) placed in the ear canal. This type of hearing aid is most often fit with plastic domes for coupling, which are not custom and can be regularly replaced. The two groups of patients who will be most often advised to pursue traditional ear molds would be those with severe to profound hearing loss and pediatric patients.

    However, there is a group in between who can use RIC/RITE hearing aids based on their degree of hearing loss, but they have difficulty with domes. This group can benefit from what is often known as a “micro mold.” It is a custom earpiece that the receiver fits into, so that the patient can use this type of hearing aid but benefit from the retention and the tighter seal offered from a custom ear mold.
hearing aid ear molds
Image Credit: www.advhearingaid.com

Customization and Individual Needs

The two most important decisions regarding ear molds are the shape and material. These are likely going to be dictated in large part by the degree of hearing loss. Another factor will be dexterity; your audiologist or hearing aid dispenser will want to ensure you will be able to successfully put your hearing aids on properly. Any allergies will also be considered when choosing materials, and your own feelings about the aesthetics can weigh in, too.

In addition to these choices, your provider will also select the canal length. This decision is a gentle balance between comfort and sound quality: getting the sound closer to the ear canal is ideal, but if the ear mold is too deep, it can be uncomfortable and/or difficult to insert. 

A vent is also an option on an ear mold order form; this is a hole drilled through the earmold that provides physical comfort through airflow to the ear canal and can alleviate the occlusion effect. This is the sensation that low-frequency sounds, particularly your own voice, are disproportionately loud. There are different vent sizes, the selection of which is determined by the degree of hearing loss. A pressure vent is just a pin prick of a hole, with increasing sizes all the way up to “as large as possible” given the size of the ear canal and the way the sound bore is positioned. 

Finally, the hearing care provider will select the tubing that connects the ear mold to the hearing aid. There are a few varieties, and the choice is based upon the degree of hearing loss and body chemistry. Sometimes tubing with a horn is selected to provide extra emphasis on high frequencies, perhaps when they cannot be fully attained through programming.

Sometimes, the audiologist will order the ear mold from the same manufacturer as the hearing aid, while others use manufacturers that solely produce custom molds (such as Westone). You can trust that your audiologist or hearing aid dispenser has worked with different ear mold companies and likely has reasons for choosing one over another. You should ask about the cost of the ear molds, as well as warranties for service, loss, and damage.

Common Concerns 

There are some common complaints or concerns that can come up with ear molds, particularly with newly fit molds. Many are easily alleviated with minor modifications, either to the ear mold itself or to the hearing aid programming, or both.

  1. “My own voice sounds muffled” or “My own voice sounds too loud.”: These are two different manifestations of the occlusion effect mentioned earlier. Adding a vent or expanding an existing vent can help, and hearing aid software now includes compensatory programming for the occlusion effect, which can reduce the emphasis on low-frequency amplification. The audiologist will want to strike a balance between maintaining good audibility of low-frequency sounds for the best hearing performance, while simultaneously finding comfort in listening for the patient.
  2. Feedback: This is the whistling sound that occurs when amplified sound escapes the ear and is re-amplified by the hearing aid microphones, creating a “feedback loop.” Again, this is an issue that can be resolved with a mixture of physical modification to the ear mold and programming of the digital hearing aid.

    Sometimes, it involves taking a new impression of the ear if the mold is not fitting snugly enough; other times, it may mean closing a vent or reducing the vent size. All of the prescription hearing aid manufacturers have sophisticated feedback management algorithms, as well. The software is able to run a feedback test and make adjustments based on the coupling method, so it could also be as simple as re-running this test.
  3. Pain or sores: Sometimes, even with the most accurate ear mold impression, a sore or pain point can develop in the ear. In these cases, the ear mold can be shaved or filed down, depending on the material, to alleviate the pressure in that area.

    There are a variety of tools used by audiologists and hearing aid dispensers to modify ear molds; this is part of the training they undergo to fit patients with hearing aids. Do not hesitate to let your provider know if your ear mold is not comfortable. If modification isn’t successful, the ear mold can be remade with an indication to the manufacturer about where the pain is occurring or potentially made in a different material and/or shape.

Caring for Hearing Aid Ear Molds

Hearing aid ear molds are generally low maintenance and should last a long time if they are well taken care of. The individual body chemistry of each patient can affect the longevity of the ear mold, as can the weather/climate, particularly the humidity level. However, there are some general rules of thumb that will make your ear mold last as long as possible.

How do I clean my ear molds?

With an earmold, always check to see if there is wax or other debris in the opening or anywhere along the tubing. You should also check to ensure your tubing is soft and supple- if it becomes hard or discolored, it’s time to have it changed by your audiologist. Some earmolds also include a vent or a small hole through the mold, which should remain clear for comfort and ventilation. Your earmold should be wiped with a soft cloth or tissue when you remove your hearing aids. Try to avoid using alcohol or other chemicals which may break down the material.

How should I remove my ear mold from my hearing aid?

First, you should try to avoid separating your ear mold and your hearing aid too frequently as it can put wear and tear on both the tubing and the ear hook. The tubing can be quite tricky to replace and will likely need to be done by your audiologist or hearing aid dispenser. Therefore, if you do have to remove the ear mold, you should remove the tubing and ear mold together from the ear hook on the hearing aid. You may need to do this if you see moisture or wax in the tubing.

Hold the hearing aid in one hand with your fingers firmly pinching the ear hook. With your other hand, gently coax the tube off the ear hook, taking care not to twist the ear hook too much. (Note: some ear hooks screw on and others click into place, but if you do accidentally take the ear hook off, you should be able to put it back on.)

If moisture is a problem, your audiologist may have already provided you with a little tool to insert at one end of the tube and blow any water droplets through to the other side. Conversely, you can use a drying kit to remove any moisture. For wax, you can thread a piece of fishing line or dental floss through the tube to pull wax out.

How often do I need to have my tubing and/or ear molds replaced?

This will depend entirely on your body chemistry and how you care for your ear molds, as well as the material of the molds. The tubing will likely need to be replaced every few months, while the ear molds may last more than a year. If sound quality is diminished or you notice that your ear molds or tubing are hard or discolored, it is a good idea to consult with your hearing care professional to see if anything needs replacing.

Hearing Aid Ear Molds Conclusion

As you can see, there is quite a lot to consider when selecting ear molds for behind-the-ear hearing aids. Fortunately, much of the decision-making regarding material, shape, and style is going to be dictated by your type and degree of hearing loss. You should have a collaborative conversation with your audiologist or hearing aid dispenser to hear what their recommendations are and contribute your thoughts on aesthetics, comfort, your own dexterity to insert the ear molds, and any allergies you might have to synthetic materials.

It is important to remember that, like hearing aids, ear molds can come with warranties. That means that if you are not satisfied with the look, comfort, or performance of the ear mold, it can be remade in a different style. Sometimes, it takes a little troubleshooting to find the right fit, and that can be a combination of ear mold modifications and hearing aid programming in the software. 

erin edwards aud
Clinical Audiologist at Towson University | + posts

Erin Edwards received her Doctor of Audiology degree from Towson University in 2015 and her Ph.D. in Education and Leadership from Pacific University in 2022. She has worked with patients of all ages in a variety of settings and has a specific interest in cochlear implants, the relationship of hearing loss and dementia, and interdisciplinary healthcare.

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