Abstract: An otoplastic for a hearing aid, which otoplastic is manufactured from a UV light-curable synthetic resin composition, in particular an acrylate composition, to which a ceramic filler including at least 50% by weight Al2O3 is added to improve the properties of the otoplastic.

Abstract: An in-the-ear hearing aid has a collar which can form a flexible seal in the bony part of the ear canal so as to reduce the occlusion effect. The collar comprises a tubular portion which is engageable against the wall of the ear canal, a fixing portion and a curved sealing portion. Owing to the use of this collar it is not necessary to make a mold of the bony part of the ear canal. This collar enables the hearing aid to be constructed in a manner such that it can be inserted so deep into the ear.

Abstract: In a method of manufacturing an in-the-ear hearing aid an auxiliary element, whose cross-section is larger than that of an auditory canal, is introduced into the auditory canal. As a result, the auditory canal is expanded. Subsequently, a hollow vent tube is inserted into the auditory canal, after which the auditory canal is filled with a viscous material. After the viscous material has solidified the mold is removed from the auditory canal. The vent tube insures that air is admitted to a space behind the mold. The mold thus formed has a cross-section larger than the cross-section of the auditory canal. Subsequently, a housing for the hearing aid is made, the mold being used as a template. Consequently, the heating aid will fit tightly in the auditory canal, which improves the wearing convenience.

Abstract: In a method of manufacturing an in-the-ear hearing aid (25), a mould (23) is made of an ear canal for use as a moulding die for making a housing of the hearing aid. After the mould is made an auxiliary tool made up of a flexible tube (11) with a flange at one end is inserted into the ear canal into the proximity of the tympanic membrane of the ear. Subsequently, a curable material (19) is introduced into the ear canal. The material presses the flange against the tympanic membrane, which precludes the ingress of material between the flange and the tympanic membrane. After the material has cured the mould with the tube and the flange is removed from the ear canal. During removal of the mould the space between the tympanic membrane and the mould is in communication with the outer air via the tube, so that no partial vacuum is produced which otherwise might damage the tympanic membrane. The mould obtained is used as a moulding die for making a custom made in-the-ear hearing aid.

Abstract: A pull-out string for connection to a hearing aid which is constructed for use in an ear canal near a tympanic membrane. The pull out string has two ends and a fixing element at each end for connection to the hearing aid. The pull-out string has a plurality of beads, the distance from each bead to an end of the pull-out string being unique. In a method of manufacturing a hearing aid provided with such a pull-out string, the pull-out string is secured to the hearing aid at one end and is severed at a desired distance from the hearing aid such that the pull-out string has a bead at the resulting free end. This results in a hearing aid having a pull-out string whose length can be chosen from many possible values and whose free end can be gripped satisfactorily.