Which earmold material is most prone to feedback with more severe hearing loss?

Acrylic/Lucite earmolds are most prone to feedback with more severe hearing loss due to their rigid structure and smooth surface, which may not create as effective a seal in the ear canal compared to other materials. When there is a more significant hearing loss, it is necessary for the hearing aid to deliver more amplification. If there are gaps between the earmold and the ear canal, sound can escape, leading to the possibility of feedback.

Silicone, while flexible and able to provide a better seal, can also be used effectively in cases of more severe hearing loss since it conforms better to the shape of the ear as it can accommodate changes in the ear canal size. Polyvinylchloride, on the other hand, is often used for its durability and can also minimize feedback but might not be as effective as silicone in terms of achieving a snug fit.

It is important to recognize the relationship between earmold material, the level of hearing loss, and how different materials interact with the shapes and surfaces of the ear canal. This dynamic aspect is crucial for minimizing feedback and ensuring the best possible hearing aid performance.