GB2084072A - A method of forming an impression of the inside of an ear - Google Patents
A method of forming an impression of the inside of an ear Download PDFInfo
- Publication number
- GB2084072A GB2084072A GB8128113A GB8128113A GB2084072A GB 2084072 A GB2084072 A GB 2084072A GB 8128113 A GB8128113 A GB 8128113A GB 8128113 A GB8128113 A GB 8128113A GB 2084072 A GB2084072 A GB 2084072A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ear
- former
- impression
- hardenable
- passage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
- H04R25/65—Housing parts, e.g. shells, tips or moulds, or their manufacture
- H04R25/652—Ear tips; Ear moulds
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F11/00—Methods or devices for treatment of the ears or hearing sense; Non-electric hearing aids; Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense; Protective devices for the ears, carried on the body or in the hand
- A61F11/06—Protective devices for the ears
- A61F11/08—Protective devices for the ears internal, e.g. earplugs
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/38—Moulds or cores; Details thereof or accessories therefor characterised by the material or the manufacturing process
- B29C33/3842—Manufacturing moulds, e.g. shaping the mould surface by machining
- B29C33/3857—Manufacturing moulds, e.g. shaping the mould surface by machining by making impressions of one or more parts of models, e.g. shaped articles and including possible subsequent assembly of the parts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C39/00—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor
- B29C39/02—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C39/026—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor for making articles of definite length, i.e. discrete articles characterised by the shape of the surface
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
- H04R25/65—Housing parts, e.g. shells, tips or moulds, or their manufacture
- H04R25/658—Manufacture of housing parts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/38—Moulds or cores; Details thereof or accessories therefor characterised by the material or the manufacturing process
- B29C33/3842—Manufacturing moulds, e.g. shaping the mould surface by machining
- B29C33/3857—Manufacturing moulds, e.g. shaping the mould surface by machining by making impressions of one or more parts of models, e.g. shaped articles and including possible subsequent assembly of the parts
- B29C2033/3871—Manufacturing moulds, e.g. shaping the mould surface by machining by making impressions of one or more parts of models, e.g. shaped articles and including possible subsequent assembly of the parts the models being organic material, e.g. living or dead bodies or parts thereof
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Neurosurgery (AREA)
- Signal Processing (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biophysics (AREA)
- Psychology (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Vascular Medicine (AREA)
- Animal Behavior & Ethology (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Mechanical Engineering (AREA)
- Prostheses (AREA)
Abstract
A method of forming an impression of the inside of an ear comprises arranging for a former, having a base and a projecting portion and provided with a through hole extending from the base to the tip of the projecting portion, to be coated with a layer of hardenable impression material so as not to block the through passage. The coated former is then inserted into the ear and the coated layer of impression material is allowed to harden to form an impression of the inside of the ear. preferably the former is pre-formed by introducing hardenable impression material into the inside of the ear and allowing it to harden. The former is then removed from the ear and the through passage is formed therein.
Description
SPECIFICATION
A method of forming an impression of the inside of an ear
This invention relates to a method of forming an impression of the inside of an ear, e.g. a human ear, to be used in the subsequent manufacture of ear inserts or earmolds, e.g. for hearing aids, as plugs for swimmers or noise abatement use, or to assist stammerers or tinnitus sufferers.
Previously impressions of the inside of an ear have been formed by inserting impression material into the external acoustic meatus of the ear using a syringe, by pouring or by employing the most widely used finger-pressing method, allowing the impression material to harden and finally removing the finished impression from the inside of the ear.
However it has been found that impressions which do not accurately reproduce the inside of the ear are produced by this known method since the inside of the ear is often distorted by the act of inserting the impression material into the inside of the ear and pressing the inserted impression material to conform to the shape of the inside of the ear.
In many applications such "inaccurate" impressions, although undesirable, are tolerated. However in the manufacture of hearing aids for very deaf people, where high powered hearing aids instead of ordinary hearing aids are employed to enable the deaf people to hear, it is essential for accurate ear inserts or earmolds to be produced so that the high powered hearing aids can be used at maximum volume without feedback problems. With the known method of forming an impression of the inside of an ear it has proved difficult to obtain easily the desired accuracy of reproduction of the inside of an ear to enable earmolds of sufficient quality to be produced for such high powered hearing aids. Consequently the earmold has to be subsequently modified to obtain the desired quality or the hearing aid has to be operated at less than full volume.
The present invention seeks to provide an improved method of forming an accurate impression of the inside of an ear.
According to the present invention a method of forming an impression of the inside of an ear comprises providing a coating of a hardenable impression material on a former having a base and a projecting portion extending therefrom, the former having a through passage therein which passes from the base of the former, through the projecting portion of the former to emerge at or adjacent the tip of the projecting portion, the coating of hardenable impression material not blocking said through passage, inserting the coated former into the inside of the ear with the coated base positioned in the outer ear and the coated projecting portion positioned in the external acoustic meatus, allowing the coated impression material to harden and removing the hardened impression from the inside of the ear.
The provision of the through passage in the coated former allows air to escape from behind the coated former as it is inserted into the inside of the ear. Thus the air pressure on either side of the coated former is equalised as the coated former is positioned so as to be fully seated inside the ear.
It may be necessary on inspection of the hardened impression to repeat the method one or more times, the "former" being constituted by the hardened impression which is removed from the inside of the ear.
Preferably, in a particularly advantageous embodiment of the invention, the former is initially formed by inserting hardenable impression material to fill the inside-of the ear, allowing the impression material of the former to harden to form the former with its said base and projecting portion but without the said through passage, removing the former from the ear, and providing the said through passage in the former. Conveniently, a canal plug, e.g. a small piece of cotton wool or sponge material attached to a length of thread, is inserted into the external acoustic meatus prior to inserting the hardenable impression material of the former in the inside of the ear. Such a canal plug is also preferably employed during any subsequent insertions of the coated former into the inside of the ear.
The hardenable impression material employed for forming the former may be a putty-like material or a mixture of one or more putty-like materials and/or one or more gels suitably admixed with an activator.
Suitably the coating impression material comprises a gel mixed with an activator.
The through passage formed in the former may comprise tubing, e.g. a metal tube or plastics, such as polyethylene, tube, fitted into a pre-drilled or otherwise formed hole.
The invention will now be described, by way of example, with reference to the following nonlimitative example.
Example
The inside of a patient's ear was examined to ensure that there was no infection, no excessive build up of wax, no collapsed canals or no abnormal growths. The ear was then syringed and cleaned and all hairs removed therefrom. A small piece of cotton wool (or sponge) was then tied to a piece of nylon thread and inserted into the external acoustic meatus of the patient. This cotton and string (i.e. the so-called "canal stop") serves to plug the external acoustic meatus and protect the ear drum so that impression material to be used subsequently for forming an ear impression does not flow into the ear drum.
A quantity of hardenable impression material was then prepared according to the manufacturer's instructions. Although many types of hardenable impression materials may be used, in the present example 17 - 20 g of putty-like material, e.g. Eden putty was mixed with 3 - 20 g of an activator or hardener, e.g. Eden gel, the Eden putty and Eden gel both being obtainable from Edenvale Laboratories of 10, Balcarres Road, Musselburgh, EH21 7SD.
The mixed impression material was then pressed into the inside of the patient's ear whilst the material was still in workable state by the well-known fingerpressing method. After approximately 2 minutes when the impression material had set hard, the impression was withdrawn from the patient's ear and a hole of varying diameter was cut in the impression to extend from a base of the impression to a free end of a meatus projecting portion extending from the base. A polyethylene tube (having an internal diameter of from 1 mm to 3 mm, typically 2,5 mm) was then fitted in the hole.
Further impression material comprising 2 g of gel material mixed with 21 g of activator was then thoroughly mixed and applied by brush or with the aid of a spatula overthe impression taking care not to cover the ends of the tube so ensuring that the tube was not blocked. The coated impression was then gently replaced in the ear and the coating material was allowed to set. The impression was then removed from the ear and inspected to see if there were any defective areas. If a defective area is found, a further coating of hardenable impression material is provided on the coated impression and the impression once again inserted into the ear and the coating allowed to set. Thus the coating step is continually repeated until a perfect impression is obtained.
It was found that the provision of the polyethylene tube in the impression allowed air to escape from behind the impression as it was inserted into the ear, thus ensuring that the ear was not excessively distorted during the formation of the impression. If air is not allowed to escape, air pressure on the ear drum prevents the impression from being fully reseated in the ear and the resulting impression has areas of air voids. A high-powered hearing aid was fitted to the finished impression at this stage to ensure that there was no feedback with the impression when the latter was inserted in the patient's ear.
If there is any feedback this can be easily rectified by coating the impression with further hardenable gel material and re-inserting the impression into the patient's ear until a final impression is obtained giving no feedback even at maximum volume of the hearing aid.
The finished impression was then employed to manufacture an earmold by pressure deforming, e.g.
vacuum drawing, a sheet of pressure deformable material over the impression to conform the sheet to the shape of the impression, separating the impression from the sheet of material without permanently disturbing the shape into which the sheet has been deformed to leave the mould cavity in the sheet material, and introducing moulding material into the mould cavity to form an earmold. Such a method of forming an earmold is described and claimed in the complete specification of my U.K. Patent No.
1,596,369.
As a preferred optional step, after cleaning and stopping the patient's ear and prior to pressing the hardenable impression material into the inside of the patient's ear to form the initial impression during making of the "former", hardenable liquid silicone material (e.g. Eden silicone spray available from
Edenvale Laboratories) is applied, e.g. sprayed into the inside of the patient's ear. Conveniently the silicone spray is applied to the inside of the ear out to the pinna by spraying two or three times in a circular
motion.
As an alternative to the step of coating the impression with further impression material by applying the latter with a brush or spatula, the impression may be coatd by dipping it into a thin solution of gel material containing an activator or by spraying it with sprayable hardenable silicone impression material to provide the impression with a uniform coating of further impression material.
Furthermore for children or adults with sensitive ears or ears having severe undercuts or thin pinnas, the initial impression of the ear can advantageously be formed without the use of the putty-like material.
In this case, hardenable, inert gel material (e.g. Eden gel) may be poured into the patient's ear so as to flow inside the ear to reproduce any undercuts. The gel material being inert does not generate any heat of reaction and will not affect the patient's ear.
The main advantage of the present invention is the employment of the through passage in the impression which enables air to be removed from the ear as the set hard impression is fully seated inside the ear.
If the through passage was not provided, the seating of such set hard impression in the ear would be accompanied by extreme pain and/orwould possibly cause damage to the ear drum. By subsequently coating the set hard impression with further hardenable impression material and reseating the coated impression in the ear, it is possible to provide an extremely accurate reproduction of the inside of the ear, even enabling severe undercuts in the ear to be reproduced. Thus it is possible, from such an impression, to form an earmold of such quality as to be usable in a high powered hearing aid with no feedback when the hearing aid is used at maximum volume.
In other embodiments of the invention, a preformed former having a passage therethrough may be provided instead of having to form a first impression and then subsequently cut a hole in the latter and fit a tube therein. However, it is preferable to form the first impression as previously described.
Furthermore, the impression obtained by the method according to the invention may be employed to make earmolds other than by the method described and claimed in the afore-mentioned U.K.
Patent No. 1,596,369.
Claims (18)
1. A method of forming an impression of the inside of an ear comprising:
(a) providing a coating of a hardenable impression material on a former having a base and a projecting portion extending therefrom, the former having a through passage therein which passes frem the base of the former, through the projecting portion of the former to emerge at or adjacent the tip of the projecting portion, the coating of hardenable impression material not blocking said through passage,
(b) inserting the coated former into the inside of the ear with the coated base positioned in the outer ear and the coated projecting portion positioned in the external acoustic meatus,
(c) allowing the coated impression material to harden, and
(d) removing the hardened impression from the inside of the ear.
2. A method according to claim 1, in which steps (a) to (d) are repeated in sequence at least one further time, the "former" in the or each repeated sequence of method steps (a) to (d) being constituted by the "hardened impression" formed at step (d) of the immediately preceding sequence of method steps (a) to (d).
3. A method according to claim 1 or 2, in which the former is initially formed by introducing harden~ able impression material into the inside of the ear, allowing the impression material oftheformerto harden to define the former with its said base and projecting portion but without the said through passage, removing the former from the ear, and providing the said through passage in the former.
4. A method according to any of the preceding claims, in which a removable canal plug is inserted into the external acoustic meatus priorto performing method step (a).
5. A method according to any of claims 1 to 3, in which, prior to performing method step (a), a removable canal plug is inserted into the external acoustic meatus and a thin layer of hardenable liquid silicone material is applied inside the ear and allowed to harden.
6. A method according to claim 5, in which the hardenable liquid silicone material is sprayed inside the ear.
7. A method according to claim 3 or any of claims 4 to 6 when dependent upon claim 3, in which the hardenable impression material employed for forming the former comprises a putty-like material or a mixture of one or more putty-like materials and/or one or more gels suitably admixed with an activator.
8. A method according to claim 3 or any of claims 4 to 6 when dependent upon claim 3, in which the hardenable impression material employed for forming the former comprises a hardenable liquid silicone material introduced into the inside of the ear.
9. A method according to claim 8, in which the former-forming hardenable liquid silicone material is introduced into the inside of the ear by means of a syringe.
10. A method according to any of the preceding claims, in which the said coating impression material comprises either a gel mixed with an activator or a hardenable liquid silicone material.
11. A method according to any of the preceding claims, in which the through passage formed in the former comprises tubing fitted in a pre-drilled or otherwise pre-formed hole.
12. A method according to claim 11, in which the said tubing has a bore of from 1 mm to 3mm in diameter.
13. A method of forming an impression of the inside of an ear substantially as carried out in the foregoing Example.
14. A method of improving the fit of an impression of the inside of an ear comprising:
(a) introducing first hardenable impression material into the inside of the ear,
(b) allowing the first hardenable impression material to harden to define a former having a portion projecting into the external acoustic meatus,
(c) removing the former from the ear,
(d) providing a through passage in the former which passage passes through the projecting portion to emerge at or adjacent the tip of the projecting portion,
(e) applying a layer of a second hardenable impression material to the projecting portion so as not to block the said through passage, the second hardenable impression material being the same material as, or different material from, the first hardenable impression material,
(f) re-inserting the former into the ear until it is fully seated therein, the coating on the former being shaped by the inside of the ear, to improve the fit of the former within the ear, under conditions in which the air pressure on either side of the coated former is equalised via said through passage,
(g) allowing the layer of second hardenable impression material to harden within the ear, and
(h) removing the hardened impression from the ear.
15. An impression formed by the method claimed in any of claims 1 to 14.
16. An improved impression of the inside of an ear comprising a former of a first hardenable impression material with a through passage therein and at least one coating of a second hardenable impression material, which coating(s) improves (improve) the fit of the former within the ear and has (have) been shaped by the inside of the ear under conditions in which the air pressure on either side of the coated former is equalised via said through passage.
17. An impression according to claim 16, in which said first hardenable impression material is the same material as said second hardenable impression material.
18. An earmold manufactured from an impression according to any of claims 15 to 17.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8128113A GB2084072B (en) | 1980-09-18 | 1981-09-17 | A method of forming an impression of the inside of an ear |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8030229 | 1980-09-18 | ||
| GB8128113A GB2084072B (en) | 1980-09-18 | 1981-09-17 | A method of forming an impression of the inside of an ear |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2084072A true GB2084072A (en) | 1982-04-07 |
| GB2084072B GB2084072B (en) | 1984-03-14 |
Family
ID=26276932
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8128113A Expired GB2084072B (en) | 1980-09-18 | 1981-09-17 | A method of forming an impression of the inside of an ear |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2084072B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0245741A1 (en) * | 1986-05-16 | 1987-11-19 | Siemens Aktiengesellschaft | Method and device for making an ear impression and transforming the ear impression into a ear mould |
| EP0289750A1 (en) * | 1987-05-06 | 1988-11-09 | Siemens Aktiengesellschaft | Method and device for making and ear tip |
| US4828777A (en) * | 1986-05-16 | 1989-05-09 | Siemens Aktiengesellschaft | Method and apparatus for the manufacture of an otoplastic shell |
| US5008058A (en) * | 1988-01-19 | 1991-04-16 | Siemens Aktiengesellschaft | Method for manufacturing an otoplastic or an ear adaptor member |
| US5131411A (en) * | 1990-08-20 | 1992-07-21 | Virginia Polytechnic Institute & State University | Custom-fitting earplug formed in situ using foaming action |
| US5440082A (en) * | 1991-09-19 | 1995-08-08 | U.S. Philips Corporation | Method of manufacturing an in-the-ear hearing aid, auxiliary tool for use in the method, and ear mould and hearing aid manufactured in accordance with the method |
-
1981
- 1981-09-17 GB GB8128113A patent/GB2084072B/en not_active Expired
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0245741A1 (en) * | 1986-05-16 | 1987-11-19 | Siemens Aktiengesellschaft | Method and device for making an ear impression and transforming the ear impression into a ear mould |
| US4828777A (en) * | 1986-05-16 | 1989-05-09 | Siemens Aktiengesellschaft | Method and apparatus for the manufacture of an otoplastic shell |
| US4834927A (en) * | 1986-05-16 | 1989-05-30 | Siemens Aktiengesellschaft | Method and apparatus for producing an ear impression |
| EP0289750A1 (en) * | 1987-05-06 | 1988-11-09 | Siemens Aktiengesellschaft | Method and device for making and ear tip |
| US4871502A (en) * | 1987-05-06 | 1989-10-03 | Siemens Aktiengesellschaft | Method for manufacturing an otoplastic |
| US5006055A (en) * | 1987-05-06 | 1991-04-09 | Siemens Aktiengesellschaft | Apparatus for manufacturing an otoplastic |
| US5008058A (en) * | 1988-01-19 | 1991-04-16 | Siemens Aktiengesellschaft | Method for manufacturing an otoplastic or an ear adaptor member |
| US5131411A (en) * | 1990-08-20 | 1992-07-21 | Virginia Polytechnic Institute & State University | Custom-fitting earplug formed in situ using foaming action |
| US5440082A (en) * | 1991-09-19 | 1995-08-08 | U.S. Philips Corporation | Method of manufacturing an in-the-ear hearing aid, auxiliary tool for use in the method, and ear mould and hearing aid manufactured in accordance with the method |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2084072B (en) | 1984-03-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |