Ear model function and type introductio
The fit of the hearing aid ear mold not only plays an important role in the hearing aid itself, but also the suitability of the wearer. The following hearings provide you with a summary of the functions and types of ear molds, so that you can better understand the importance of ear molds and help you choose the type of hearing aids.
First, the function of the ear mold:
1Fixed hearing aid
The ear mold is completely made according to the various parts of the outer ear of the hearing aid wearer, and has the physiological structure of the external ear canal, the ear arm cavity, the ear armor and the like, so that the hearing aid can be worn more firmly, not easy to fall off, and can also increase the wearer’s Comfort.
2Assisting the hearing aid to transmit sound
When the ear mold or earplug is not tightly sealed and the hearing aid output volume is large, the output speech and ambient sound will leak through the external auditory canal, and the second feedback of the hearing aid will cause acoustic feedback, which can not satisfy the severe or severe hearing impairment. Listening to the needs, therefore, it is necessary to make ear molds for such people.
3Improve acoustic properties
The length of the ear mode channel and the size of the sound hole will directly affect the characteristics of sound conduction. Therefore, through the change of the shape and size of the two passes, it can compensate for some deficiencies in the learning characteristics of the hearing aid to a certain extent, thereby improving the hearing aid effect. . Some wearers may have a blocked ear phenomenon. By increasing the listening hole, the ear can be well relieved.
Second, the type of ear mold
According to the size of the logical external auditory canal occupied by the ear mold, the ear mold can be divided into a plug type and a non-block type.
The ear plug ear mold can be divided into standard type, shell type, skeleton type (frame type), half shell type, ear canal type, ear wheel ear canal lock type ear mold and the like. Since many ear molds have a low probability of being used clinically, here I mainly introduce several clinical common ear molds.
1) shell ear mold: it has a relatively complete ear and ear lock, and has a high degree of firmness and airtightness. Because the shell ear mold occupies the entire ear cavity, the outer ear canal has good sealing, which can prevent the occurrence of howling. Therefore, the patient sometimes feels uncomfortable in the ear part. The ear mold can be polished into a thin shell to reduce the weight and increase the aesthetic effect. This ear mold is suitable for patients with severe to very severe hearing loss.
2) Skeleton (frame) ear mold: similar to the shell ear mold, but without the central part of the ear, in order to increase patient comfort, the central part of the shell ear mold can be hollowed out, leaving only the edge of the bone ring, Embedded in the ear cavity. In this way, the weight of the ear mold is reduced, and the area where the ear mold is in contact with the auricle is reduced, thereby improving the comfort of wearing the ear mold. This ear mold is suitable for patients with mild, moderate and partial severe hearing loss.
3) half-shell ear mold: half-shell ear mold, also known as ear shell shell ear mold. The ear canal portion of the ear mold is removed, and the ear mold covers only the portion of the ear cavity. The half-shell ear mold is suitable for patients with inflexible fingers and mild to moderate hearing loss, and is generally the majority of elderly patients.
4) Ear canal ear mold: This ear mold retains only the outer ear canal. Because it has the least contact area with the outer ear, it is the most comfortable to wear and easy for the patient to wear. However, its firmness and tightness are poor.
2Non-blocking ear mold
The most characteristic feature of the non-blocking ear mold is that it completely eliminates the wearer’s discomfort and completely preserves the auricle effect of the outer ear and the external auditory canal.