A cleaning device for a voice prosthesis and method of manufacturing the cleaning device

Abstract

A cleaning device for a voice prosthesis including a brush element extending along a longitudinal axis of the cleaning device including a core column of twisted steel wire and a first plurality of individual filaments extending from the brush portion of the core column. An intermediate portion of the filaments is attached to the brush portion so that each filament extends generally radially from the core column. At least one of two opposing end portions of each individual filament is configured to form a bristle being at a predetermined first angle to the core column and pointing in the direction of the distal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

Description

[0001] A CLEANING DEVICE FOR A VOICE PROSTHESIS AND METHOD OF MANUFACTURING THE CLEANING DEVICE

[0002] A cleaning device for a voice prosthesis and a method of manufacturing the cleaning device is provided in the following disclosure.

[0003] Background

[0004] A total laryngectomy is a surgery performed in the advanced stages of laryngeal cancer. The procedure involves removing the voice box or larynx. After a laryngectomy, breathing happens via an opening in the neck instead of the nose and mouth as there is no longer a connection between the lungs and nose and mouth. Therefore, a neck stoma is created for respiration. To enable speech, the patient can have a puncture created between the oesophagus (foodpipe) and the trachea (windpipe). This is done by performing a tracheoesophageal puncture (TEP) procedure. A small hole or puncture is created in the tissue between the trachea and the oesophagus. This can either be done at the time of the total laryngectomy surgery or during a second subsequent surgical procedure.

[0005] In most cases, a suitable device including a one-way valve is inserted in the TEP already during the laryngectomy procedure. Such a device may be known as a voice prosthesis. The one-way valve of the voice prosthesis protects the airway during swallowing but opens under positive pressure on the tracheal side. The voice prosthesis thereby permits a patient to divert air from the lungs into the oesophagus and out through the mouth. Speech is created during passage of air through the upper part of the oesophagus. The voice prosthesis maintains the puncture open, transfers air from the trachea to the oesophagus for voice (speech) production and prevents oesophageal leakage into the trachea during swallowing.

[0006] The oral cavity which extends into the throat has a high microbial population. A voice prosthesis being in contact with moisture in a hot, dark nutrient rich environment is subject to growth of microorganisms commonly found in the oral cavity and upper airways, typically Candida, on the valve mechanism of the voice prosthesis and on the portions of the voice prosthesis configured to keeping it in place in the TEP. The microbial growth onto the surfaces of the voice prosthesis can interfere with the valve function and causes leaks. Leaks through the puncture in the tissue can also occur along the outer periphery or edges of the voice prosthesis due to microorganism ingrowth on these portions or due to an insufficient fit between the voice prosthesis and the tissue around the puncture. Moreover, leaks can also be caused by food residues entering from the oesophagus side and / or by mucus interfering with the valve function of the voice prosthesis.

[0007] As it is desired to ensure the best possible functionality of a voice prosthesis for as long as possible, solutions exist which allow the user or patient to clean the voice prosthesis sitting in its use position in a TEP, particularly the internal surfaces and the valve mechanism of the voice prosthesis. It is advantageous that cleaning is done frequently, such as several times a day, e.g., after each consumption of at least solid foodstuffs. One type of solution involves brushes. One example of a brush for cleaning a voice prosthesis is disclosed in publication number WO 02 / 064271.

[0008] Users of voice prostheses and health care professionals alike would welcome improvements in cleaning solutions for voice prostheses.

[0009] Summary

[0010] In one aspect, the present disclosure relates to a cleaning device for a voice prosthesis. In another aspect, the disclosure relates to a method for manufacturing a cleaning device for a voice prosthesis as described herein. The aspects are further defined by the appended claims.

[0011] Brief Description of the Drawings

[0012] The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The figures illustrate embodiments and together with the description explain principles of embodiments. Other embodiments and many of the intended advantages of all embodiments will be readily appreciated as they become better understood by reference to the following detailed description. Various exemplary embodiments and details are described hereinafter, with reference to the figures when relevant. It should be noted that the figures may or may not be drawn to scale and that elements of similar structures or functions are represented by like reference numerals throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the embodiments. They are not intended as an exhaustive description of the invention or as a limitation on the scope of the invention. In addition, an illustrated embodiment needs not have all the effects or advantages shown. An effect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and may be practiced in other embodiments even if not so illustrated, or if not so explicitly described.

[0013] The figures can be listed as follows:

[0014] Figure 1A is a top view illustrating a cleaning device extending through a voice prosthesis, the cleaning device being according to one embodiment of the present disclosure.

[0015] Figure IB is a cross-sectional side view according to the cross-section indicated by arrows / line A-A in Fig. 1A.

[0016] Figure 1C is an enlarged cross-sectional view of a brush element of the cleaning device extending through the voice prosthesis according to the indication of the portion marked with circle C in Fig. IB.

[0017] Figure 2 is a cross-sectional view of a brush element according to one embodiment.

[0018] Figure 3 is a schematic view through an exemplary voice prosthesis.

[0019] Figure 3B is a schematic cross-sectional view through an exemplary voice prosthesis.

[0020] Figure 4 is a schematic illustration showing a voice prosthesis 10 located in a user.

[0021] Figure 5 is a schematic view illustrating one embodiment of a cleaning device according to the disclosure inserted into a voice prosthesis located "in situ" in a tracheoesophageal puncture (TEP) of a user.

[0022] Figure 6 is a schematic illustration indicating a unit length "L" on a brush element disclosed herein. Figure 7 is a schematic perspective view illustrating embodiments of a brush element of a cleaning device according to the disclosure.

[0023] Figure 8 is a boxplot graphically illustrating an improved cleaning efficacy of a brush element of a cleaning device according to the disclosure.

[0024] Figure 9 is a schematic perspective view illustrating one embodiment of a brush element of a cleaning device according to the disclosure.

[0025] Detailed Description

[0026] In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "back," "leading," "trailing," etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is not necessarily limiting. It is to be understood that other embodiments may be utilized, and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. In this application, the term "proximal" or "proximal direction" signals that something is towards the (center of) the user's body, and the term "distal" or "distal direction" signals that something is away from the (center of) the user's body.

[0027] It is to be understood that individual features of the various exemplary embodiments described herein may be combined with each other, unless specifically noted otherwise.

[0028] In this disclosure, a person or subject using the cleaning device may be referred to as "patient" or "user". However, in some cases, "user" can also relate or refer to a health care professional (HCP), such as a doctor / physician, nurse, or other person.

[0029] In this disclosure, 'axially' or 'axial direction' should generally be considered as being along or parallel to a described longitudinal axis of a thing. The radial direction should be understood as being at an angle to the axial direction. In some sentences, the words "inner" and "outer" can be used. These qualifiers should generally be perceived with reference to the radial direction, such that a reference to an "outer" element means that the element is generally farther away from a centre portion of a component than an element referenced as "inner". In addition, "innermost" should be interpreted as the portion of a component forming a centre of the component and / or being adjacent to the centre of the component. In analogy, "outermost" should be interpreted as a portion of a component forming an outer edge or outer contour of a component and / or being adjacent to that outer edge or outer contour. In further analogy this is also the case regarding the use of the words "upper" / "lower" and "uppermost" / "lowermost".

[0030] The use of phrases such as (but not limited to) "substantially" and "approximately" as qualifiers of certain features or effects in this disclosure, is intended to simply mean that any deviations are within tolerances that would normally be expected by the skilled person in the relevant field.

[0031] The use of the word "generally" as a qualifier to certain features or effects in this disclosure is intended to mean - for a structural feature: that a majority or major portion of such feature exhibits the characteristic in question, and - for a functional feature or an effect: that a majority of outcomes involving the characteristic provide the effect but that, exceptionally, some outcomes may not provide the effect.

[0032] In the present disclosure, the term "filament(s)" is to be understood as thin or slender natural or synthetic fibers or strands, or as an object that looks like fibers or strands.

[0033] In the present disclosure, the term "bristle(s)" is to be understood as the hairs or fibers / strands, natural or synthetic, as provided in a brush of a brush element according to the disclosure.

[0034] In the present disclosure, the larynx or voice box, is to be understood as the part of the respiratory (breathing) tract containing the vocal cords which produce sound. A total laryngectomy means the surgical removal of the larynx and separation of the airway from the mouth, nose, and oesophagus. A tracheostomy (or -stoma) is a hole (opening) made in the skin in the front of the neck to allow breathing. The stoma is made at the base of the neck. Air goes in and out of the trachea and lungs through this hole. In a first aspect, the present disclosure relates to a cleaning device for a voice prosthesis including a brush element extending along a longitudinal axis of the cleaning device. Optionally, the cleaning device includes a handle element configured to be attached to the brush element. In embodiments, the handle element is attached to the brush element at manufacture. In other embodiments, the handle element is provided separately allowing users to attach the handle element themselves to the brush element. This is advantageous for making the handle element suitable for longterm repeated use e.g., with substitutable brush elements. In some implementations, the brush element according to the disclosure can be configured as a single-use element or device. Generally, however, the disclosed brush element is designed for repeated uses. In other embodiments, the cleaning device can be provided without a handle element. One effect of this is that it facilitates use of the brush element with different types of handle elements. This can be advantageous in cases where a user has dexterity challenges and therefore may need a customized or personalized handle element to be able to best perform cleaning.

[0035] The brush element includes a core column of twisted steel wire. The core column includes a proximal end portion, a distal end portion, and a brush portion. The brush portion can be understood to extend between the proximal end portion and the distal end portion of the core column. The 'core column' should be understood as a central-most part of the brush element forming an oblong longitudinal central axis of the brush element and constitutes a 'backbone' or 'spine'-like feature of the brush element, sometimes also referred to as a 'stem' of the brush element.

[0036] The brush element includes a first plurality of individual (brush) filaments extending from the brush portion of the core column.

[0037] An intermediate portion of each individual filament of the first plurality of filaments is attached to the brush portion of the core column so that each individual filament extends generally radially from the core column. In embodiments, each individual filament is attached to the twisted steel wire of the core column at their intermediate portion (e.g., by having been placed in the gap between two parallel legs of a piece of bent steel wire upon which the steel wire is twisted, thereby making the steel wire securely pinch on the filaments for their attachment). At least some of the intermediate portion of each filament is in contact with the steel wire and extends generally transverse to the longitudinal axis of the cleaning device (longitudinal axis here defined through the core column of the brush element). It is further to be understood that any portion of each of the individual filaments located radially outward of (free from contact with) the steel wire can be at an angle to the longitudinal axis different from 90°. In embodiments, the angle can vary in steps or continuously along the radial length of the filament, such as to provide a curved arrangement of the filament along at least a portion of the radial length thereof.

[0038] At least one of two opposing end portions of each individual filament of the first plurality of filaments is configured to form a bristle being at a predetermined first angle to the core column and pointing in the direction of the distal end portion of the core column seen relative to the longitudinal axis of the cleaning device. Generally, the filament end portions forming a bristle are all at the substantially same uniform predetermined first angle to the core column.

[0039] Further, those filament end portions of the individual filaments of the first plurality of filaments forming a bristle, all point in the same direction, which is the distal direction of the cleaning device and thus towards the distal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

[0040] Moreover, as used in this application, the wording "is configured to form a bristle being at a predetermined first angle" means that the end portions of those filaments forming a bristle at manufacture undergo treatment to make them all generally form said predetermined first angle to the core column, but that occasionally, due to production tool tolerances and / or influence from external factors (e.g., handling during or after manufacturing and / or packaging), a minority of bristles of the brush element end-product may form (an)other angle(s) with the core column.

[0041] One advantageous effect of the above-described structure of the brush element of the cleaning device for a voice prosthesis is that the brush element is more effective in cleaning components of the valve mechanism of the voice prosthesis compared to currently available cleaning device solutions. Keeping the valve mechanism of the voice prosthesis as clean as possible can be critical to the intended correct functioning of the voice prosthesis, as described above.

[0042] One particularly advantageous effect of the cleaning device according to the disclosure is that the sealing surface(s) of the valve seat of the valve mechanism of the voice prosthesis can be more effectively cleaned, which has been confirmed by tests involving prototypes of the described brush element. In this disclosure, a valve seat is to be understood as a generally annular ring of a suitable material forming a sealing surface on which the valve flap of the voice prosthesis rests when closed. The shape of the valve seat surface can be defined by an outer contour being adjacent to other portion of the voice prosthesis and by an inner contour being in alignment with the walls of an inner lumen of the voice prosthesis). Both the inner and outer contours can include both linear and curved sections whereby the valve seat surface can have a e.g., non-symmetrical or irregular shape. Ideally, the valve flap always remains closed when speech is not initiated by the user. This will as an example also include the situations when the user is eating and thus swallowing food and liquids. A standard cleaning procedure for cleaning a voice prosthesis with a brush as currently available on the markets includes the insertion and rotation of the brush in the voice prosthesis. Such standard cleaning procedure is also equally suitable and useful for the cleaning device including a brush element as disclosed herein.

[0043] Particularly, tests have been conducted wherein prototype brush elements each having different outer diameter and each with bristles resultantly forming different predetermined first angles to the core column of the brush element were tested for valve seat cleaning efficacy and measured against the cleaning efficacy of an existing cleaning solution comprising a brush forming bristles with an approximate 90° angle to the longitudinal direction of the cleaning device. The results of the tests generally indicate that angling of the bristles of the brush element provides a distinct and significant improvement in cleaning efficacy over the existing solution, particularly and at least up to a certain optimal level of resulting angling determined by the effective diameter of the bristles of the manufactured brush element. In other words, angling of the bristles of the brush element is found to have a high marginal benefit up until a certain level of angling, based on measurements that show that (otherwise identical) prototype brushes with different effective diameters between 3.5mm and 4.5mm exhibit similar cleaning efficacy, while being distinctly better than an existing brush with straight (90° angle) bristles.

[0044] One reason for the proposed brush element of the cleaning device being more efficient in cleaning of the valve seat of the voice prosthesis is found to be that the predetermined first angle arrangement of the bristles pointing towards the sealing surface of the valve seat, results in an increased (higher) level of friction in the direction of the valve seat during a brushing action (the bristles of the first plurality of filaments point towards the distal end of the core column of the brush element, thus when the brush element is inserted into a voice prosthesis and used for cleaning by back and forth movements, the distally pointing bristles point towards and engage with the valve seat in the voice prosthesis). The higher level of friction induced by the angled bristles on the sealing surface of the valve seat is believed to be suitable and useful for ensuring that food residues and / or mucus on the valve and the valve seat are more efficiently removed during brushing. Thus, even very viscous, or sticky or otherwise cumbersome-to-remove food residues and / or mucus can be more efficiently removed. However, the angled bristles are also likely useful for targeting beginning regions of microorganisms, such as Candida, if the valve seat is of a material prone to microorganism ingrowth. One theory is that this is because the friction provides for the bristles to press or squeeze entirely through the microorganism layer on the valve seat, and thereby lets the bristles undermine the microorganism layer from underneath them (i.e., attacking the surface below the microorganisms).

[0045] When carrying out the brush element prototype testing regime mentioned above, it was further found that the predetermined first angle arrangement of the bristles of the first plurality of filaments does not significantly compromise the brush element's efficiency in cleaning other portions of the voice prosthesis, such as particularly the inner lumen extending through the voice prosthesis, providing the passageway for air. As explained above, occasionally some bristles may have end portions forming a different angle with the core column deviating from the predetermined first angle with the core column formed by a majority of bristles - in this regard, it is noted that except if the level of bristles of different angle(s) influences the generally improved cleaning efficiency of the brush element, such minority deviations (in terms of number of bristles with another angle than the predetermined first angle) do not place such "deviating" brush elements outside the scope of the appended claims.

[0046] In embodiments, the predetermined first angle is an angle in the range from 5- 60 degrees, such as 10-55 degrees, such as 15-45degrees, such as 25-40 degrees, such as approximately 30 degrees. In one embodiment, the predetermined first angle is approximately 27 degrees. In embodiments, the predetermined first angle can be understood as the tangential angle of an end-most portion of each individual filament of the first plurality of bristle filaments to the (longitudinal axis through the) core column. The proposed range for a suitable predetermined first angle is found to provide the bristles with a more aggressive angle of attack towards the sealing surface(s) of the valve seat of the voice prosthesis, which in turn provides more efficient cleaning thereof.

[0047] In embodiments, the radially extending filaments of the first plurality of filaments of the brush element provide the brush element with a(n) (approximate) radius, which is suitably arranged to make the brush element proportional to a diameter of an inner lumen of a voice prosthesis to be cleaned. In embodiments, the radially extending filaments of the first plurality of filaments of the brush element provide the brush element with a(n) (approximate) radius, which is suitably arranged to make the brush element proportional to a diameter of the valve seat of a voice prosthesis to be cleaned. Hereby, proportional does not necessarily mean that the brush element is provided with an outer diameter identical to an inner diameter of a given size of VP but may also mean proportionally smaller or larger than the inner diameter, and / or the diameter of the valve seat of the VP in question.

[0048] In embodiments, a radial length of each individual filament is in a range of 1.5 - 4.5 mm. This range of radial length of the individual filaments is found to ensure the suitability of the filaments for being both securely attached to the core column of twisted steel wire and sufficiently long to ensure cleaning of all portions of a voice prosthesis, including reaching entirely across a diameter of the valve seat of the largest model of voice prosthesis. In embodiments, before the brush element undergoes treatment (curing) as described below, the radially extending filaments of the first plurality of filaments of the brush element are configured to provide the brush element with an approximate diameter of 3.0 mm. In one embodiment, the diameter before curing is approximately 4.0 mm. In one embodiment, the diameter before curing is approximately 4.4 mm. In one embodiment, the diameter before curing is approximately 4.6 mm. In one embodiment, the diameter before curing is approximately 4.8 mm. In one embodiment, the diameter before curing is approximately 5.2 mm. In one embodiment, the diameter before curing is approximately 5.4 mm. In one embodiment, the diameter before curing is 5.65 mm. In one embodiment, the diameter before curing is approximately 5.8 mm. In one embodiment, the diameter before curing is approximately 5.9 mm. In one embodiment, the diameter before curing is approximately 6.0 mm. In one embodiment, the diameter before curing is approximately 6.5 mm. In one embodiment, the diameter before curing is approximately 7.0 mm.

[0049] The size of lumens in medical devices are often measured in the unit "French", abbreviated Fr. Examples of sizes of voice prostheses addressed by the claimed range of lengths of the individual filaments include voice prostheses of size ranging from 17 Fr and up to at least 22.5 Fr. These sizes of voice prostheses exhibit approximate valve seat diameters ranging from about 4.4 mm to about 6.0 mm.

[0050] In embodiments, after the brush element has undergone treatment (curing) as described below, the radially extending filaments of the first plurality of filaments of the brush element provide the brush element with an approximate diameter in a range of

[0051] 3.5 - 5.0 mm. It is understood that not each and every individual filament of the first plurality of filaments necessarily provide the brush element with the exact specified diameter. Instead, it is understood that generally the first plurality of the filaments in combination exhibits the specified approximate diameter. In one embodiment, the diameter after curing is approximately 3.5 mm. In one embodiment, the diameter after curing is approximately 3.6 mm. In one embodiment, the diameter after curing is approximately 3.7 mm. In one embodiment, the diameter after curing is approximately 3.8 mm. In one embodiment, the diameter after curing is approximately 3.9 mm. In one embodiment, the diameter after curing is approximately 4.0 mm. In one embodiment, the diameter after curing is approximately 4.1 mm. In one embodiment, the diameter after curing is approximately 4.2 mm. In one embodiment, the diameter after curing is approximately 4.3 mm. In one embodiment, the diameter after curing is approximately 4.4 mm. In one embodiment, the diameter after curing is approximately

[0052] 4.5 mm. In one embodiment, the diameter after curing is approximately 5.0 mm. In one embodiment, the diameter after curing is approximately 5.5 mm.

[0053] The filaments of the first plurality of filaments are attached to the twisted steel wire along the longitudinal axis at the brush portion of the core column. Considering or looking at the locations where the intermediate portion of each individual filament is attached to the core column of twisted steel wire, the attachments of the filaments are distributed along the longitudinal axis of the core column in an axially progressing and "turning" or "coiling" manner around the longitudinal axis. Thus, in embodiments, the end portions of the individual filaments of the first plurality of filaments forming the bristles are arranged in accordance with a helical distribution pattern along the longitudinal axis at the brush portion of the core column. Such helical distribution pattern of the bristles provides that the valve seat is not contacted by all the bristles simultaneously over its entire surface during cleaning of the sealing surface(s) of the valve seat of a voice prosthesis. This configuration and its effect is advantageous in that it reduces the magnitude of the combined, distally directed force exerted on the valve seat during cleaning with the brush element, while still ensuring and achieving locally (i.e., on a portion of the valve seat being less than an entirety thereof) the benefit of the improved cleaning of the sealing surface(s) of the valve seat, as described above. A reduced magnitude of the combined, distally directed force exerted by the bristles on the valve seat reduces discomfort for the user when brushing and reduces or eliminates the possibility of exceeding a force-threshold for unintended dislocation of the voice prosthesis from its position in the TEP, due to the brushing / cleaning by the movements of the brush back and forth in the voice prosthesis.

[0054] In embodiments, the first plurality of filaments is attached to the twisted steel wire over a minimum length of approximately 4 mm and up to a maximum length of approximately 25 mm measured along the longitudinal axis of the cleaning device. This length range provides for designing the brush element for the cleaning device for a voice prosthesis to accommodate a full range of voice prostheses sizes. In embodiments, the brush element in its entirety can be of different lengths, e.g., accommodating for different lengths of the brush portion of the core column and the longitudinal extent of where the filaments forming the bristles are provided. It is advantageous that the cleaning device and voice prosthesis can form a combined offering with suitable mutually corresponding dimensions to best accommodate for different user anatomies, and for allowing users to securely use the cleaning device for cleaning in the vicinity of the delicate body tissue of the airways. In embodiments, the first plurality of filaments is attached to the twisted steel wire over a length of approximately 15 mm.

[0055] In embodiments, the brush portion of the core column of the brush element overlaps with the proximal end portion of the core column of the brush element. This means that the first plurality of filaments is attached to the twisted steel wire of the core column over an entirety of the brush portion and the proximal end portion. In other words, the filaments are attached to the core column (and extending therefrom) over both the brush portion and the proximal end portion. Thereby, the plurality of filaments substantially extends to a proximal end of the core column of the brush element ('substantially' here meaning that the proximal-most filaments are at or just adjacent the proximal end of the brush element).

[0056] In embodiments, the proximal end portion of the core column of the brush element is of minimal length seen in relation to a total length of the brush element. In embodiments, a reduced-length proximal end portion of the core column can be used for attachment of an oesophageal-tissue protective means immediately adjacent to the (proximal-most end of the) brush portion of the core column. This arrangement can be useful for a cleaning device adapted for smaller lengths in the range of voice prosthesis sizes.

[0057] In embodiments, a distribution density of the filaments of the first plurality of filaments is in a range of 40 to 400 filaments per unit length L. In one implementation, the distribution density of the filaments can be understood as the number of units of filament per 'one axial length of a full winding of the two legs of the steel wire' (one full "coil winding") around the longitudinal axis of the brush element of the cleaning device (note that in embodiments, one unit of filament can be regarded as equalling two bristles as each individual filament extends radially from the core column at the brush portion in two directions). For reference, the axial length of one full coil winding can be referred to as the unit length "L". In embodiments, one full coil winding, i.e., the unit length "L", is approximately 3mm. In embodiments, the number of filaments is in a range of 100-120 per full coil winding / per unit length. In embodiments, this corresponds to approximately double the number of bristles, i.e., a range of approximately 200-240 bristles.

[0058] In embodiments, a distribution density of the filaments of the first plurality of filaments towards a proximal end segment and / or towards a distal end segment of the brush portion is in a lower end of the range proposed above, such as in a range of 40 - 100 filaments per unit length L. In embodiments, a distribution density of the filaments of the first plurality of filaments at a middle segment of the brush portion is in a higher end of the range, such as in a range of 200 - 400 filaments per unit length L. In embodiments, a distribution density of the filaments of the first plurality of filaments at a middle segment of the brush portion is in a range of 180 - 220 filaments per unit length L. In embodiments, a thickness of each individual filament of the first plurality of filaments is in a range of 0.04 mm to 0.20 mm. In embodiments, the thickness of each individual filament of the first plurality of filaments is in a range of 0.05 mm - 0.15 mm. In embodiments, the thickness of each individual filament of the first plurality of filaments is approximately 0.05 mm - 0.06 mm. It is believed that a filament thickness of approximately 0.05 mm - 0.06 mm ensures that a force applied to pull out the brush element of a voice prosthesis after cleaning is at a comfortable level for the user. If the pull-out force required would be too high, irritation of the TEP and / or general discomfort for the user could occur. In embodiments, the thickness of each individual filament of the first plurality of filaments is 0.064 mm (2.5 mils, a mil being 1 / 1000 of an inch). In embodiments, the thickness of each individual filament of the first plurality of filaments is 0.076 mm (3.0 mils). In embodiments, the thickness of each individual filament of the first plurality of filaments can be in a range of 0.064 mm - 0.076 mm (2.5-3.0 mils). However, it is found that a filament thickness in the higher end of the proposed range, such as approximately in the range of 0.10 mm - 0.15 mm, could also incur an acceptable pull-out force of the brush element if the distribution density of the filaments is concurrently in the lower end of the range proposed above, such as in the range of 40 - 100 filaments per unit length L.

[0059] In embodiments, the core column comprises a spacer portion extending along the longitudinal axis between the proximal end portion of the core column and the brush portion of the core column. The spacer portion can be understood to provide additional length to the core column of the brush element. Additional length of the core column can be useful particularly for voice prostheses of the larger dimensions, e.g., used in larger anatomies. In embodiments, inclusion of a spacer portion can provide room for additional elements and thus functionality of the brush element, if required.

[0060] In embodiments, the spacer portion has a length being in a range of 1-10 mm, such as 2-9 mm, such as 3-8 mm, such as 4-7 mm, such as 5-6 mm, such as approximately 5.5 mm. This range of lengths of the spacer portion provides accommodation of a majority of voice prostheses sizes and provides flexibility in options for designing a cleaning device for voice prostheses in that these can include additional features, including additional cleaning means, safety means, and / or other functional means. In embodiments, the spacer portion comprises a second plurality of individual filaments wherein an intermediate portion of each of individual filament of the second plurality of filaments is attached to the spacer portion so as to extend generally radially from the core column, and wherein at least one of two opposing end portions of each individual filament of the second plurality of filaments is configured to form a bristle being at predetermined second angle to the core column and pointing in the direction of the proximal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

[0061] In embodiments, wherein the brush element includes a second plurality of individual filaments wherein at least one of two opposing end portions of each individual filament forms a bristle being at predetermined second angle to the core column and pointing in the direction of the proximal end portion of the core column, additional functionality is added to the brush element according to the disclosure. This will be explained in more detail below. In some implementations, a bristle formed by one of the individual filaments of the second plurality of filaments may be referred to as a 'valve-flap bristle'.

[0062] Similar to the manner in which the individual filaments of the first plurality of filaments are attached to the brush portion of the core column, an intermediate portion of each individual filament of the second plurality of filaments is attached to the spacer portion of the core column so that each individual filament extends generally radially from the core column. In embodiments, each individual filament of the second plurality of filaments is attached to the twisted steel wire at the spacer portion of the core column by the intermediate portion (in the same manner of attachment as the first plurality of filaments described above). At least some of the intermediate portion of each individual filament of the second plurality of filaments is in contact with the steel wire and may extend generally transverse to the longitudinal axis of the cleaning device (longitudinal axis here defined through the spacer portion of the core column). It is further to be understood that any portion of each of the individual filaments of the second plurality of filaments located radially outward of (free from contact with) the steel wire, can be at an angle to the longitudinal axis different from 90°. In embodiments, the angle can vary in steps or continuously along the radial length of the filament, such as to provide a curved arrangement of the filament along at least a portion of the radial length thereof. Similar to the first plurality of bristle filaments, at least one of the two opposing end portions of each individual filament of the second plurality of filaments is configured to form a bristle being at a predetermined second angle to the core column and pointing in the direction of the proximal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

[0063] Generally, the filament end portions of the second plurality of filaments forming a bristle are all at the substantially same uniform predetermined second angle.

[0064] Further, those filament end portions of the individual filaments of the second plurality of filaments forming a bristle ('valve-flap bristle') all point in the same direction, which is in the proximal direction of the cleaning device and thus towards the proximal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

[0065] Moreover, as used in this application, the wording "is configured to form a bristle being at a predetermined second angle" means that the end portions of those filaments of the second plurality of filaments forming a bristle, at manufacture undergo treatment to make them all generally form the predetermined second angle to the core column, but that occasionally, due to production tool tolerances and / or influence from external factors (e.g., handling during or after manufacturing and / or packaging), a minority of the bristles formed by the second plurality of filaments of the brush element, in the end-product may form (an)other angle(s) with the core column.

[0066] Generally, it is to be understood that in embodiments implementing a second plurality of filaments extending radially from the spacer portion of the core column, the at least one of two opposing end portions of each of the individual filaments of the second plurality forms a bristle which is pointing proximally, i.e., generally in the opposite direction (towards the other end of the cleaning device) than the distally pointing bristles formed by the first plurality of filaments.

[0067] In embodiments, the predetermined second angle of the at least one of two opposing end portions of a filament of the second plurality with the core column, is different from the predetermined first angle of the at least one end portion of each of the individual filaments of the first plurality of filaments forming a bristle.

[0068] In embodiments, the predetermined second angle is an angle in the range from 10-35 degrees, such as 15-30 degrees, such as 20-25 degrees, such as approximately 25 degrees. In embodiments, the predetermined second angle can be understood as the tangential angle of an end-most portion of each individual filament of the second plurality of bristle filaments to the (longitudinal axis through the) core column. The proposed range for the predetermined second angle is found to provide the bristles formed by the second plurality of filaments with a suitable angle of attack towards the surface of the valve flap, which valve flap surface faces towards the valve seat of the valve mechanism of the voice prosthesis.

[0069] The proposed angle of attack of the bristles helps provide additional efficient cleaning of the valve flap of the valve mechanism of the voice prosthesis during cleaning with the cleaning device in the voice prosthesis (this effect or functionality can be obtained and / or reinforced by subsequent / repeated movements of the cleaning device in and out of the voice prosthesis).

[0070] In embodiments, a handle element is fixedly attached to the brush element. In this disclosure, "fixedly" attached is intended to mean that when a handle element and a brush element are fixedly attached to each other, the connection between them is secure and stable and not intended to be separated again (and this cannot be done without breaking the cleaning device). In embodiments, the twisted steel wire of the distal end portion of the core column of the brush element is integrated with a proximal end portion of the handle element. In embodiments, the brush element and the handle element are permanently attached to each other during manufacture of the cleaning device. In embodiments, the handle element is an injection moulded handle element. In embodiments, the injection moulded handle element is configured to include an elongated internal lumen in at least a proximal end portion of the handle element suitable for receiving and engaging with the distal end portion of the core column of the brush element. In other embodiments, the distal end portion of the core column can be attached to an external surface of the handle element at the proximal end portion thereof. In embodiments, the proximal end portion of the handle element can include a reinforcement portion useful for stabilizing and supporting the steel wire and its attachment to the handle element.

[0071] In embodiments, the handle element is an elongated rod-like element, preferably made from a suitable plastics material, such as, but not limited to, polypropylene (PP) or acrylonitrile butadiene styrene (ABS). In embodiments, the handle element suitable has a total length of in the range of approximately 12-20 cm, such as approximately 15 cm. In embodiments, the handle element suitable has a total length of in the range of approximately 9-12 cm, such as approximately 10.5 cm. In embodiments, the handle element can include one or more flanges extending generally transverse to the longitudinal direction of the rod-like element. The one or more flanges are generally arranged to provide a safety means, having an extent in a direction to the longitudinal axis of the cleaning device, which is greater than the stoma opening in the user's neck, to ensure against unintentional slipping of the cleaning device into the trachea and lungs of the user. The one or more flanges can additionally help provide the user with a more convenient and secure grip on the handle element. In embodiments, the handle element can include one or more surface portions formed to provide increased grip for the user's fingers, such as by providing the handle element with one or more carvings and / or a roughened or textured surface. In embodiments, the handle element includes a further radially extending stop flange provided at or near the proximal end portion of the handle element. The stop flange is adapted to prevent the cleaning device, and particularly the brush element, from being inserted too far into the voice prosthesis. The stop flange can be provided by an increased diameter of the handle element at the proximal end portion, the diameter being greater than an inner lumen of the voice prosthesis.

[0072] In other embodiments, the handle element and the brush element are configured to be attached and detached from each other. Such attachment and detachment action is intended to happen outside of a manufacturing setting, e.g. allowing for a user's own substitution of brush elements to be used with a re-useable handle element.

[0073] In embodiments, the proximal end portion of the core column comprises a protective means adapted for protection of the oesophageal tissue of a user. In embodiments, the protective means can be attached to the proximal end portion of the core column of the brush element. In embodiments, the protective means can include a plastic material element including a generally rounded external surface, e.g., a shaped as a ball or spherical plastic element into which the proximal end portion of the core column of the brush element extends and attaches safely to. In embodiments, the protective means can be provided by a location on the steel wire used for forming the core column of the brush element, where the steel wire has been manipulated to include a 180-degree bend and thus forms two parallel legs, which are then subsequently coiled into the core column's twisted steel wire by a twisting or coiling action. The 180-degree bend can be adapted to sufficiently provide a suitably safe rounded surface for contact with oesophageal tissue, or, the 180-degree bend of the steel wire may too additionally be equipped with a ball or spherical plastic element. Other embodiments of protective means are acceptable. The protective means provides for secure insertion of the cleaning device into (and through the valve of) the voice prosthesis (while the voice prosthesis is sitting in the TEP in the user / patient). The tissue of the oesophageal walls is delicate and very sensitive to externally induced effects, and by including the protective means insertion of the cleaning device and cleaning of the voice prosthesis can be done even more safely.

[0074] In embodiments, suitable materials for the filaments of the brush element include nylon (polyamides), polyester, or polypropylene. Other materials can be acceptable provided they are processible to provide the angled bristles of the brush element in accordance with the disclosure.

[0075] It is to be understood that, in embodiments, regarding parameter values, dimensions, material choices, described ways of arranging, and other variables, any relevant description relating to the individual filaments of the first plurality of filaments is also applicable to the individual filaments of the optional second plurality of filaments, except where otherwise different values, effects, and / or arrangements etc., are explicitly mentioned and / or described, in particular concerning different angles and angle ranges.

[0076] In another aspect, the disclosure relates to a method for manufacturing a cleaning device according to the first aspect. The cleaning device is configured for cleaning a voice prosthesis, particularly a voice prosthesis of the types referred to in this disclosure. The method for manufacturing the cleaning device includes the steps described below.

[0077] Step (a) involves providing a brush element comprising a core column of twisted steel wire comprising a proximal end portion, a distal end portion, and a brush portion, and comprising a first plurality of individual filaments extending radially from the brush portion of the core column.

[0078] According to one implementation, a brush element "blank" (the wording "blank" to be understood as a partially prepared goods intended to be further processed) is provided, e.g., received from a supplier, and then subjected to processing according to the manufacturing method disclosed herein. In other implementations, the manufacturing method can additionally include one or more initial steps of preparing the brush element blank, e.g., including at least steps of providing a steel wire, and twisting or coiling it to for example a coil-like shape with the filaments attached thereto.

[0079] Regarding the filaments, the brush element blank can be provided to include at least a first plurality of filaments. As described, the filaments are arranged to extend radially from the brush portion of the core column. In some implementations, at least one of the two opposing end portions of each of the individual filaments of the brush element blank extend generally perpendicular to the core column (meaning that the at least one end portion of the individual filament is substantially at a 90-degree angle to the core column).

[0080] Step (b) involves providing a fixture comprising a rotational symmetrical hole which comprises at least a first longitudinal segment having a diameter which is less than a largest width of the brush element. In this context, "longitudinal" segment is intended to mean that the first segment of the hole in the fixture has a larger extent in a first direction than in a second, transverse direction of the fixture. In embodiments, the larger extent in a first direction can be considered a depth of the hole in the fixture. The rotational symmetrical hole of the fixture can include more segments than the first segment. In case there are two or more segments, each individual segment can be rotational symmetrical. In case there are two or more segments, the different segments of the rotational symmetrical hole can have different diameters. At least one segment (here 'the first') has a diameter which is less (smaller) than a largest width of the brush element. In a general sense, the rotational symmetrical hole in the fixture is configured to receive parts, or an entirety, of the twisted steel wire including attached filaments, and to be used in the manufacturing method for providing the brush element according to the disclosure. The fixture can thus be understood to be a type of work-holding or support device as known in manufacturing industry. The rotational symmetrical hole can suitably be provided e.g., by milling various segments along a common axis in the fixture with different-sized (milling) tools. In embodiments, the fixture is configured as a stand-alone production support device or tool that can be moved between different workstations / locations. In embodiments, the fixture comprises aluminium. In embodiments, the fixture is made from aluminium. In embodiments, the fixture is a metal fixture made by 3D printing using a printing material of metal (SLS, Selective Laser Sintering). As can be understood, at least one segment of the rotational symmetrical hole (here: the "first" segment) is configured to have a diameter which is less (smaller) than a largest width of the brush element. The notion 'a largest width of the brush element' is to be understood in relation to the width of the brush element blank described above under step (a): it is the largest distance between the end portions of two bristle filaments extending farthest (longest distance) away from each other in opposite transverse directions in relation to the longitudinal axis on the brush element blank. In embodiments of aluminium and 3D printed metal fixtures, the fixture can advantageously include one or more holes and / or cavities around the rotational symmetrical hole. This may help reduce the mass of the fixture facilitating easier and quicker heating and cooling. Moreover, such holes and / or cavities can further provide canals for additional heating and / or cooling and for other or additional manipulation of the brush element in the fixture during the curing.

[0081] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is in a range of approximately 2.3mm - 5.3mm.

[0082] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is in a range of approximately 3.5mm - 5.0mm.

[0083] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 2.3 mm.

[0084] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.4 mm.

[0085] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.5 mm.

[0086] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.6 mm. In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.7 mm.

[0087] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.8 mm.

[0088] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 3.9 mm.

[0089] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.0 mm.

[0090] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.1 mm.

[0091] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.2 mm.

[0092] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.3 mm.

[0093] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.4 mm.

[0094] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.5 mm.

[0095] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 4.6 mm.

[0096] In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 5.0 mm. In embodiments, at least one segment of the rotational symmetrical hole, such as the "first" segment, is configured to have a diameter which is approximately 5.3 mm.

[0097] In embodiments, the rotational symmetrical hole in the fixture is arranged as a cylindrical hole. In embodiment, the rotational symmetrical hole in the fixture is arranged as a cylindrical hole formed as one (single) longitudinal segment having the same diameter over the entire length of the segment. In embodiments, the rotational symmetrical hole in the fixture is arranged to include two or more longitudinally extending segments, each of cylindrical shape, wherein each individual segment is arranged with different diameters of the cylindrical shape. In embodiments, the rotational symmetrical hole in the fixture is arranged as a truncated-cone shaped hole.

[0098] Step (c) involves inserting at least the brush portion of the core column of the brush element into the first longitudinal segment of the rotational symmetrical hole of the fixture so that the proximal end portion of the core column enters the hole first, thereby causing at least one of the two opposing end portions of each individual filament of the first plurality of filaments to flex and form a bristle pointing in the direction of the distal end portion of the core column.

[0099] This means that at least the first longitudinal segment of the rotational symmetrical hole in the fixture provides a portion of the hole that is so configured that it causes the end portions of the individual filaments to bend in a direction which is opposite to the direction of insertion. As the proximal end portion of the core column of the brush element is entering (being inserted) the hole first, the end portions of the individual filaments along the brush portion of the core column are flexed and (then) form a bristle pointing in the direction of the distal end portion of the core column. According to step (c) of the manufacturing method, the brush element is not necessarily inserted entirely into the hole in the fixture. As long as at least the brush portion of the core column of the brush element is inserted in the first longitudinal segment of the hole in the fixture, the relevant filament end portions are flexed to form bristles pointing in the direction of the distal end portion of the core column. Therefore, if the brush portion of the brush element is so inserted that the bristles will be formed, a remainder of brush element does not necessarily have to be inserted as well, thus the brush element can be understood to be 'at least partially inserted' into the fixture. Step (d) involves placing the fixture with the at least partially inserted brush element in an oven and curing the brush element at a temperature in a range of 170- 200°C for a period of 10-30 minutes. In embodiments, the oven temperature according to step (d) of the method is in a range of 170-220°C. In a specific embodiment, the oven temperature according to step (d) of the method is approximately 180°C. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 18 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 19 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 20 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 21 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 22 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is in a range of 22-30 minutes.

[0100] In an alternative approach, step (d) involves placing the fixture with the at least partially inserted brush element in an oven and curing the brush element at a temperature in a range of 90-140°C for a period of 1-10 minutes. In embodiments, the oven temperature according to step (d) of the method is in a range of 125-135°C. In a specific embodiment, the oven temperature according to step (d) of the method is approximately 130°C. In a specific embodiment, the oven temperature according to step (d) of the method is approximately 90°C. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 2 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 3 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 4minutes. In a particular embodiment, the period in which the brush element is cured in the oven according to step (d) of the method is approximately 5 minutes. In embodiments, the period in which the brush element is cured in the oven according to step (d) of the method is in a range of 5-10 minutes. Alternatively, or additionally, to step (d), in a sub-step (d-sub) a source for blowing hot air into and / or around the fixture containing the brush element can be provided and applied to reduce the time it takes to reach the relevant fixture / brush element temperature in the center of the fixture. In one test set-up, a relevant temperature in the center of the fixture was reached in approximately 10 minutes using a source of hot air. In embodiments, the hot air is being blown into at least one segment of the fixture.

[0101] With respect to the manufacturing parameters and / or settings, such as particularly one or more of those of step (d) of the method, it has been found the oven temperature (curing temperature) affects the level of bristle rebound after cool-down. An investigation of the bristles of otherwise identical brush elements, which were cured in fixtures, each fixture provided with a cylindrical hole of identical diameter throughout (one longitudinal segment of fixed diameter), at different oven temperatures ranging from 170° - 2000C, revealed that bristles cured at a temperature in the higher end of the range better retain the incurred bend and thus predetermined angle to the longitudinal axis. The angle, at which the bristles meet the valve seat, further affects how the bristles engage with and slide across the sealing surface of the valve seat, as the cleaning device is moved axially by the user during brushing / cleaning, and consequently affects the level of cleaning of the surface.

[0102] Step (e) involves removing the fixture with the at least partially inserted, cured brush element from the oven and allowing the fixture to cool. In embodiments, the method includes letting the fixture containing the cured brush element cool off for approximately 20 minutes. In embodiments, the fixture cools to room temperature before any further activity or processing involving the fixture, and / or the at least partially inserted, cured brush element, is carried out. In embodiments, the fixture and the brush element cool to below room temperature before any further activity or processing is carried out. In embodiments, the cooling includes blowing cool, compressed air on the bristles while they are still inserted or partially inserted in the fixture. Using a source of cooled air and blowing the cool air into and / or around the fixture can further reduce the production time of the brush element.

[0103] Applying an accelerated manner of heating the fixture (or at least one or more relevant segments thereof) with the inserted brush element in it, to the curing temperature, and applying a subsequent accelerated cooling, has been found to combine to reduce the total production time of a brush element significantly, while not reducing the quality of the curing process of the brush element and hence not reducing the quality and ability of the brush element to improve the cleaning of the valve seat of the voice prosthesis.

[0104] Step (f) involves removing the cured brush element from the fixture by pulling it out of the fixture with the distal end portion of the core column exiting first. In other words, the cured brush element is removed from the fixture by pulling it out of the same end / side of the fixture at which the brush element blank was inserted. The resulting cured brush element includes bristles provided with a semi-permanent deformation in the form of the angle incurred to the bristles by the equipment / tools used in and the steps of the manufacturing method ("semi-permanent" in the sense that the bristles will be affected by the use for cleaning of the voice prosthesis by repeated stroking in and out of the voice prosthesis).

[0105] The manufacturing method can optionally include an additional step (g) involving attaching a protective means to the proximal end portion of the core column of the brush element. In embodiments, the protective means is a generally rounded plastic element, such as a spherical plastic element into which the proximal end portion of the core column of the brush element is inserted and safely attached to, e.g., by a press-fit connection, injection moulding, and / or by a gluing step. Other manners of embodying optional step (g) of the manufacturing method are acceptable. Alternatively, optional step (g) of attaching a protective means can be implemented prior to any of the other step (b) to (f) of the manufacturing method. The choice of material of the protective means can influence the optimal timing of the optional step (g) of attaching the protective means. In embodiments, the protective means can be attached already to the brush element blank. In embodiments, the protective means can be injection moulded onto the brush element.

[0106] The manufacturing method can optionally include an additional step (h) (with or without the manufacturing method also including the optional step (g)). Optional step (h) involves attaching a handle element to the brush element. In embodiments, the handle element is an injection moulded handle element, which includes an elongated internal lumen in at least a proximal end portion of the handle element into which the distal end portion of the core column of the brush element is arranged and processed for being fixedly attached. In embodiments, the distal end portion of the core column of the brush element is attached to an external surface of the handle element at the proximal end portion thereof by gluing. Other manners of embodying optional step (h) of the manufacturing method are acceptable.

[0107] In embodiments, if relevant, one or both optional steps (g) and (h) can alternatively be carried out before the brush element is cured in an oven according to step (d) and optionally sub-step (d-sub) of the manufacturing method. In such events, the fixture can suitably be arranged to accommodate an entirety of the cleaning device, i.e., the cleaning device then including both the brush element and the handle element and / or a protective means according to step (g). In embodiments, the protective means and the handle element can be attached to the brush element in the same manufacturing step.

[0108] In embodiments, a length of the first longitudinal segment of the rotational symmetrical hole of the fixture is longer than a length of the brush element in its entirety. This arrangement ensures that an entirety of the brush element can be retained in the hole and that all the filaments of the brush element can be processed to be angled in relation to the longitudinal axis at the same time.

[0109] In embodiments, the rotational symmetrical hole of the fixture comprises two or more additional segments, each additional segment having a diameter dimension and a length dimension being different from the diameter dimension and the length dimension of the first longitudinal segment. In embodiments, the fixture includes two longitudinal segments. One advantageous effect of having two or more segments is that one or more segments can be provided in which the brush element with the bristles will not be processed to have a predetermined first angle with the longitudinal axis. In one embodiment, the hole in the fixture is arranged so as to be able to process the brush element to have different predetermined angles along the longitudinal axis. In one example, the brush element can have shorter bristles from the middle of the brush portion and towards the distal end portion of the core column, which shorter bristles may therefore not be engaged by the walls of the fixture hole and thus remain at an approximate 90° angle to the longitudinal axis. Thereby, a diameter of the brush element at this portion can be provided to match an inner lumen of a specific size voice prosthesis. Thereby, the shorter bristles are perpendicular to the inner lumen of the specific size voice prosthesis, which can be useful for the effect of the local cleaning of the inner lumen walls. At the same time, a portion of the brush element towards the proximal end portion of the core column may then have the angled bristles, particularly suitable for the cleaning action of the valve seat of the voice prosthesis, which has a different spatial orientation than the inner lumen of the voice prosthesis. In embodiments, the fixture can be arranged to include a hole including one segment forming a tapered hole (i.e., having varying diameter along the depth of the hole). In embodiments, the manufacturing of the cleaning device and particularly the processing of the bristles is arranged such that the resulting brush element has a first brush portion with bristles at a predetermined first angle to the longitudinal axis and a second brush portion with bristles being substantially perpendicular to the longitudinal axis. This can be useful for effectively cleaning both the inner lumen and the valve seat of the voice prosthesis with the same brush element.

[0110] In embodiments, the steps of the manufacturing method, such as at least steps (b) - (f), can be repeated using the same or a different fixture to process the filaments of a second plurality of filaments to form bristles having a predetermined second angle to the longitudinal axis which point towards the proximal end portion of the core column of the brush element. In embodiments, processing of a first plurality of filaments and processing of a second plurality of filaments can be interchanged, i.e., such that the second plurality of filaments is processed before the first plurality of filaments. In embodiments, processing of the first and the second plurality of filaments (to have different angled, oppositely pointing bristles) can be carried out simultaneously, e.g., by arranging the hole in a fixture in accordance with one or more of the structural implementations proposed above.

[0111] Experiments

[0112] Table 1 below shows measurements of the resulting predetermined angle of the bristles to the core column after treatment and curing of a brush element according to the manufacturing method described in this disclosure. Table 1 illustrates the resulting predetermined first angle versus treatment using fixtures with rotation symmetrical holes of different diameters. The tested brush elements all had an initial diameter before treatment and curing of the bristles of 5.5 mm, a filament thickness of 0.064 mm (2.5 mils), a bristle density of -100-120 filaments (200-240 bristles) per coil winding of the steel wire, and the different test specimen were cured in the fixtures for a period of 20-30 minutes and at 180°-200°C.

[0113] Table 1

[0114] Table 2 below shows the resulting cleaning efficacy (measured as the percentage of a colouring pigment provided on the valve seat of voice prostheses) of brush elements after treatment and curing of a brush element according to the manufacturing method described in this disclosure under the conditions and parameters stated above in relation to Table 1. All cleaning efficacy tests were done on voice prostheses of size 22.5 FR, corresponding to a valve seat diameter of approximately 5.9 mm.

[0115] The right-hand most column of Table 2 provides comparable test results for the cleaning efficacy of an untreated brush element of a bristle diameter of 5.5 mm with bristles at 90 degrees to the longitudinal axis of the brush element. Table 2 illustrates that angling of the bristles yield a significantly improved cleaning efficacy of the brush element according to the invention compared to currently available cleaning devices with brush elements where the bristles extend straight outward from the center axis.

[0116] Table 2 Table 2 further illustrates a trend indicating an optimum cleaning efficacy relative to the predetermined first angle of the bristles of the brush element to the core column when the angle is approximately 27 degrees. However, Table 2 further illustrates that angles both smaller and greater than 27 degrees yield better results than a brush with straight bristles.

[0117] Detailed description of the drawings

[0118] Figure 1A relates to the first aspect of the present invention and is a top view illustrating a cleaning device extending through a voice prosthesis, the cleaning device being according to one embodiment of the present disclosure. Figure IB is a cross- sectional side view according to the cross-section indicated by arrows / line A-A in Fig. 1A. Figure 1C is an enlarged cross-sectional view of a brush element of the cleaning device extending through the voice prosthesis according to the indication of the portion marked with circle C in Fig. IB.

[0119] Figs. 1A, IB, and 1C illustrate one embodiment of a cleaning device 20 for a voice prosthesis 10. The cleaning device 20 includes a brush element 22 extending along a longitudinal axis CL of the cleaning device 20. In the embodiments of Figs. 1A and IB, the cleaning device 20 includes a handle element 24 attached to the brush element 22. In the embodiments of Fig. 1A and IB, the handle element 24 has been fixedly attached to the brush element 22 at manufacture.

[0120] As best shown in Fig. 1C, the brush element 22 includes a core column 26 of twisted steel wire 28. The core column 26 includes a proximal end portion 30, a distal end portion 32, and a brush portion 34. The brush portion 34 extends between the proximal end portion 30 and the distal end portion 32 of the core column 26. The core column 26 is shown as the central-most part of the brush element 22 forming an oblong longitudinal central axis of the brush element 22 and can be seen to constitute a stem of the brush element 22.

[0121] As indicated in embodiments illustrated by the view of Fig. IB, the twisted steel wire 28 of the distal end portion 32 of the core column 26 of the brush element 22 is integrated with and fixedly attached to a proximal end portion 36 of the handle element 24. In the embodiments of Figs. 1A and IB, the handle element 24 is an injection moulded handle element. As shown in Figs. IB and 1C, the injection moulded handle element 24 includes an elongated internal lumen 38 in the proximal end portion 36, which receives and engages with the distal end portion 32 of the core column 26 of the brush element 22. Also, in the embodiments illustrated by the views of Figs. 1A and IB, is an optional reinforcement portion 40 that can be useful for stabilizing and supporting the steel wire 28 and the attachment of the core column 26 to the proximal end portion 26 of the handle element 24.

[0122] In Figs. 1A and IB, the illustrated handle element 24 is an elongated rod-like element of a suitable plastics material. In the embodiments illustrated in Figs. 1A and IB, the handle element 24 includes two flanges 42a, 42b extending generally transverse to the longitudinal direction of the rod-like handle element and suitably wide to ensure against unintentional slipping of the cleaning device 20 into the trachea and lungs of the user. In embodiments, and as best shown in Fig. 1A, the handle element 24 includes surface portions in the form of carvings 44a, 44b to help provide increased grip for the user's fingers. Further illustrated is a stop flange 41 adapted to prevent the cleaning device, and thus the brush element 22, from being inserted too far into the voice prosthesis 10 during cleaning / brushing.

[0123] Turning now generally to Figure 2, which is a cross-sectional view of a brush element 22 according to one embodiment, the illustrated brush element 22 includes a first plurality 46 of individual filaments 48 extending from the brush portion 34 of the core column 26. As best shown in Fig. 1C, an intermediate portion 50 of each individual filament 48 of the first plurality 46 of filaments is attached to the brush portion 34 of the core column 26 so that each individual filament 48 extends generally radially from the core column 26 at the intermediate portion 50. This generally radial extending is indicated by indication of angle a of 90° between the central longitudinal axis CL and where the filaments 48 extend from the brush portion 34. Figs. 1C and 2 further schematically illustrate how the twisted steel wire 28 pinches on the intermediate portion 50 of the individual filaments 48 for their attachment to the brush portion 34. Portions of each of the individual filaments 48 free from contact with the steel wire 28, are at predetermined first angle, indicated in Fig. 2 as , to the longitudinal axis CL, which first angle is different from 90°.

[0124] As schematically and best indicated in Fig. 1C, the end portions 52 of each of the individual filaments 48 of the first plurality 46 of filaments form bristles 54 being at a predetermined first angle to the core column and pointing in the direction of the distal end portion 32 of the core column 26 seen relative to the longitudinal axis CL of the cleaning device 20. In Fig. 1C, and particularly looking at the bristles 54 located towards the distal end portion 32 of the core column 26, it is intended to illustrate how the individual filaments 48 of the first plurality 46 of filaments form the bristles 54 and that the bristles 54 are formed around the longitudinal axis CL through the core column 26. In other words, even if the cross-sectional views of Figs. IB and 2 illustrate a plurality of individual filaments 48 being in the (same) plane of the paper along the core column 26, the individual filaments 48 in practice extend from the core column 26 in an entire 360° rotation around the longitudinal axis CL. In Fig. 2, each of the filament end portions 52 forming a bristle 54 are shown to form generally the same uniform predetermined first angle to the core column 26. As also illustrated in Figs. IB, 1C, and 2, the filament end portions 52 of the individual filaments 48 of the first plurality of filaments 46 forming a bristle 54 all point in the same direction towards the distal end portion 32 of the core column 26 seen relative to the longitudinal axis CL.

[0125] Figure 3 is a schematic view through an exemplary voice prosthesis 10. One advantageous effect of a brush element 22 of a cleaning device 20 according to the embodiments described in this disclosure is that the novel brush element 22 is particularly effective in cleaning in particular a valve mechanism 12 of the voice prosthesis 10. Particularly, the brush element 22 of the cleaning device 20 is efficient for cleaning the sealing surface of the valve seat 16 of the valve mechanism 12 of the voice prosthesis 10. The valve seat 16 is the portion on which a distal side of the valve flap 14 of the valve mechanism 12 rests when it is closed. Figure 3B is a schematic cross-sectional view through the valve seat portion of an exemplary voice prosthesis 10, such as the one of Fig. 3. Fig. 3B does not show the valve flap of the voice prosthesis 10 but focuses on the valve seat 16. The arrows A point towards oppositely located sealing surfaces 16a, 16b of the valve seat 16 of the voice prosthesis 10. As illustrated in the view of Fig. 3B, the sealing surface of the valve seat 16 can be inclined at an angle relative to the longitudinal direction of the voice prosthesis 10, such as indicated at 16c. The surface portions 16a, 16b indicated by the arrows A, and the remainder of the sealing surface of the valve seat such as 16c exhibit an increased level of cleaned surface area using the advantageous brush element 22 of the disclosure as illustrated by the results of Table 2 above. The cleaning device according to the invention has additionally been found to be particularly efficient in cleaning portion of the sealing surface corresponding to the lowermost sealing surface portion 16b (to the right in Fig. 3B). Such a lowermost sealing surface has shown difficult to reach by the bristles of the presently available cleaning devices.

[0126] During cleaning (brushing) with the cleaning device 20 including the brush element 22 according to the embodiments disclosed herein, the arrangement of the bristles 54 formed by the end portions 52 of the individual filaments 48 of the first plurality 46 of filaments to point towards the sealing surface of the valve seat 16 (cf. Fig. 1C and 3B) results in an increased level of friction between the bristles 54 and the valve seat 16 during brushing. This efficiently removes food residues and / or mucus from the valve seat 16 and may also remove other unwanted matter.

[0127] Figure 4 is a schematic illustration showing a voice prosthesis 10 located in a user. A neck stoma has been created allowing the user to breathe. The neck stoma is covered by a heat-moisture-exchanger 11. To enable speech, the user has a puncture (TEP) created in the tissue between the oesophagus 13 and the trachea 15. A voice prosthesis 10 being in such an environment is subject to leakage from the oesophagus to the trachea caused by food residues entering from the oesophagus 13 side and interfering with the valve mechanism 12 of the voice prosthesis 10, particularly food residues settling on the valve seat 16 (Fig. 3), and / or from mucus. Such "central" leaks are illustrated by arrow Pl. Leaks through the puncture in the tissue can also occur along the outer periphery or edges of the voice prosthesis due to insufficient fit between the voice prosthesis and the tissue around the puncture which can be caused by poor tissue conditions. These "peripheral" leaks are illustrated by arrows P2.

[0128] Figure 5 is a schematic view illustrating one embodiment of a cleaning device 20 according to the disclosure inserted into a voice prosthesis 10 which is located "in situ" in the TEP of a user. When carrying out cleaning or brushing with a cleaning device 20 including a brush element 22 as disclosed herein the inner lumen 17 (Fig. 4) and particularly the valve seat 16 (Fig, 3) of the voice prosthesis 10 are effectively cleaned.

[0129] Referring again to Fig. 2, the figure illustrates one embodiment of a brush element 22 wherein the predetermined first angle of the bristles 54 is in the range from 20-70 degrees, and here approximately 45°. This is an example of one angle of attack of the bristles 54 towards the sealing surface(s) of the valve seat 16 of the voice prosthesis 10, which provides efficient cleaning thereof. In the view of Fig. 2, it is further illustrated the radially extending filaments 48 of the first plurality 46 of filaments of the brush element 22 provide the brush element with a radius <d2>, which is suitable to make the brush element 22 proportional to the diameter of the inner lumen 17 (Fig. 4) of a voice prosthesis 10 to be cleaned. In embodiments as illustrated particularly in Figs. 2 and 3, a radial length of each of individual filament 48 from the attachment to the core column 26 at the central longitudinal axis CL to the end of the bristle 54 is suitably in a range of 1.5 - 4.5 mm.

[0130] As illustrated particularly in Figs. 1C and 2, the filaments 48 of the first plurality 46 of filaments are attached to the twisted steel wire 28 along the longitudinal axis CL at the brush portion 34 of the core column 26. In the embodiments of Figs. 1C and 2, the attachments of the filaments 48 are distributed along the longitudinal axis CL of the core column 26 in an axially progressing and "turning" or "coiling" manner around the longitudinal axis. The end portions 52 of the individual filaments 48 forming the bristles 54 are arranged in accordance with a helical distribution pattern along the longitudinal axis CL. The first plurality 46 of filaments 48 is attached to the twisted steel wire 28 over a length between approximately 4 and 25 mm measured along the longitudinal axis CL of the cleaning device 20 (the figures are not to scale).

[0131] Figure 6 is a schematic illustration indicating a unit length "L" on a brush element prior to the processing incurring the predetermined first angle to the end portions 52 of the filaments 48. In this disclosure the unit length L can be understood as the axial length of one full coil winding of the twisted steel wire 28. can be referred to as "L". In embodiments, a distribution density of the filaments 48 of the first plurality 46 of filaments is in a range of 40 to 400 filaments per unit length L. In Fig. 6, the distribution density is approximately 180-220 per L. The black colouring on the end portions 52 of the filaments in Fig. 6 is simply used in testing to indicate the end portions of individual filaments 48 belonging to the same individual filament. Note that some end portions 52 being close to the steel wire 28 in the illustration are pointing towards the spectator, i.e., out of the plane of the paper.

[0132] Figure 7 is a schematic view illustrating embodiments of a brush element 22 of a cleaning device according to the disclosure. Fig. 7 includes an (A) and a (B) side showing a brush element 22. On the left side, indicated (A), the brush element 22 is not attached to a handle element 24 and does not include a protective means 56. On the right side, indicated (B), the brush element 22 is attached to a handle element 24 and includes a protective means 56 attached to a proximal end portion 30 of the core column 26. Moreover, on side (B), the first plurality 46 of filaments of the brush element 22 have not yet been processed to be arranged at a predetermined first angle. On both sides (A) and (B), the core column 26 of the illustrated brush element 22 includes a spacer portion 58 extending along the longitudinal axis CL between the proximal end portion 30 of the core column 26 and the brush portion 34 of the core column 26. The spacer portion 58 provides additional length to the core column 26 of the brush element 22.

[0133] In embodiments, as illustrated by the view of Fig. 7, the spacer portion 58 includes a second plurality 60 of individual filaments 62 wherein an intermediate portion of each of individual filament 62 is attached to twisted steel wire 28 at the spacer portion 58 of the core column 26 and extends generally radially from the core column 26. End portions 64 of each individual filament 62 of the second plurality 60 of filaments form bristles 66, being at predetermined second angle to the core column 26, and point in the direction of the proximal end portion 30 of the core column 26, seen relative to the longitudinal axis CL. The bristles 66 formed by individual filaments 62 of the second plurality 60 of filaments may be referred to as a valve-flap bristle 66. The proximally pointing bristles 66 formed by the second plurality 60 of filaments 62 can be seen in Fig. 7 (A) to generally point in the opposite direction (i.e., towards the other end of the brush element 22) than the distally pointing bristles 54 formed by the first plurality 46 of filaments 48. As is further identifiable in the view of Fig. 7 (A), the predetermined second angle of the end portion 64 of a filament 62 of the second plurality 60 with the core column 26 is different from the predetermined first angle of the end portion of each of the individual filaments 48 of the first plurality 46 of filaments forming distally pointing bristles 54. In Fig. 7 (A), the predetermined second angle is approximately 20-25°. This provides the bristles 66 with a suitable angle of attack towards a distal surface of the valve flap 14, which valve flap distal surface faces towards the valve seat 16 of the valve mechanism 12 of the voice prosthesis 10 (Fig. 3) and helps provide efficient cleaning of the valve flap 14 during cleaning / brushing with the cleaning device 20 in the voice prosthesis 10 (Fig. 5).

[0134] Figure 8 is a boxplot graphically illustrating a portion of the results according to Table 2. The subject of the x-axis is the approximate predetermined angle of the bristles after treatment and also showing (right-hand most) the result for a brush with straight bristles. Along with the indication of the approximate predetermined angle is the size of the fixture hole used to obtain the relevant angles. Regarding the sample brush element, the conditions and parameters for preparing the brushes were as stated above in relation to Table 1.

[0135] Figure 8 illustrates that angling of the bristles yield a significantly improved cleaning efficacy of the brush element according to the invention compared to currently available cleaning devices with brush elements where the bristles extend straight outward from the center axis. The results of the tests illustrated in Fig.8 generally indicate that angling of the bristles of the brush element provides a distinct and significant improvement in cleaning efficacy over the existing solution, particularly up to and around an optimal level of resulting angling of the bristles of the manufactured brush element of approximately 27 degrees. As seen from Fig. 8, the results show that angling of the bristles of the brush element has a high marginal benefit up until this level of angling, measured on otherwise identical prototype brushes with different effective diameters between 3.5mm and 5.0mm. Fig. 8 generally illustrates the benefits on bristle angling by the angled brushes exhibiting a distinctly better cleaning efficiency than a brush with straight (90° angle) bristles.

[0136] Figure 9 is a schematic view illustrating one embodiment of a brush element 22 of a cleaning device according to the disclosure. The brush element 22 is shown attached to a handle element 24 at the distal end portion 32 of the core column 26. The first plurality 46 of filaments of the brush element 22 have been processed to be arranged at a predetermined first angle. The first plurality of filaments extends along the longitudinal axis CL at the brush portion 34 to the proximal end 31 of the core column 26. As illustrated by the view of Fig. 9, the first plurality 46 of filaments including individual filaments 62, wherein an intermediate portion of each of individual filament 62 is attached to twisted steel wire 28 along the brush portion 34 of the core column 26, extends generally at the predetermined first angle from the core column 26. The bristles 54 formed by the first plurality 46 of filaments 62 generally point in the distal direction, i.e., towards the distal end portion 32 of the brush element 22. In Fig. 9, the predetermined first angle is approximately 44°. This is one embodiment according to the invention which provides the bristles 54 with a suitable angle of attack towards the relevant sealing surface of the valve seat of the voice prosthesis to be cleaned and which in turn helps provide efficient cleaning of the valve seat during cleaning / brushing with the cleaning device 20 through the voice prosthesis 10 (cf. Fig. 5).

[0137] Although particular features have been shown and described, it will be understood that they are not intended to limit the claimed invention, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the scope of the claimed invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than restrictive sense. The claimed invention is intended to cover all alternatives, modifications, and equivalents.

[0138] Index of reference numbers

[0139] 10 voice prosthesis

[0140] 11 heat-moisture-exchanger

[0141] 12 valve mechanism

[0142] 13 oesophagus of user

[0143] 14 valve flap

[0144] 15 trachea of user

[0145] 16 valve seat

[0146] 16a, 16b, 16c surface portions of valve seat

[0147] 17 inner lumen of voice prosthesis

[0148] 20 cleaning device

[0149] 22 brush element

[0150] 24 handle element

[0151] 26 core column

[0152] 28 twisted steel wire

[0153] 30 proximal end portion of core column

[0154] 31 proximal end of core column

[0155] 32 distal end portion of core column

[0156] 34 brush portion of core column

[0157] 36 proximal end portion of handle element

[0158] 38 elongated internal lumen of handle element

[0159] 40 optional reinforcement portion

[0160] 42a, 42b flanges

[0161] 44a, 44b carvings

[0162] 46 first plurality of individual filaments

[0163] 48 individual filaments

[0164] 50 intermediate portion of individual filament

[0165] 52 end portion of individual filament of first plurality of filaments

[0166] 54 bristles

[0167] 56 protective means

[0168] 58 spacer portion

[0169] 60 second plurality of individual filaments 62 individual filaments

[0170] 64 end portion of individual filament of second plurality of filaments

[0171] 66 (valve-flap) bristles

[0172] predetermined first angle <d2> radius of brush element

Claims

CLAIMS:

1. A cleaning device for a voice prosthesis, comprising:- a brush element extending along a longitudinal axis of the cleaning device, and, optionally,- a handle element configured to be attached to the brush element; wherein the brush element comprises a core column of twisted steel wire comprising a proximal end portion, a distal end portion, and a brush portion, and comprising a first plurality of individual filaments extending from the brush portion of the core column; wherein an intermediate portion of each individual filament of the first plurality of filaments is attached to the brush portion of the core column so that each individual filament extends generally radially from the core column, and, characterized in that at least one of two opposing end portions of each individual filament of the first plurality of filaments is configured to form a bristle being at a predetermined first angle to the core column and pointing in the direction of the distal end portion of the core column seen relative to the longitudinal axis of the cleaning device.

2. The cleaning device of claim 1, wherein the predetermined first angle is an angle in the range from 5-60 degrees, such as 10-55 degrees, such as 15-45 degrees, such as 25-40 degrees, such as approximately 30 degrees.

3. The cleaning device of claim 2, wherein the predetermined first angle is approximately 27 degrees.

4. The cleaning device of any one of claims 1-3, wherein the predetermined first angle varies continuously along the radial length of the individual filament, such as to provide a curved arrangement of the filament along the radial length thereof.

5. The cleaning device of any one of the preceding claims, wherein a radial length of each of individual filament is in a range of 1.5 - 4.5 mm.

6. The cleaning device of any one of the preceding claims, wherein the end portions of the individual filaments of the first plurality of filaments forming the bristles are arranged in accordance with a helical distribution pattern along the longitudinal axis at the brush portion of the core column.

7. The cleaning device of any one of the preceding claims, wherein the first plurality of filaments is attached to the twisted steel wire over a minimum length of approximately 4 mm and up to a maximum length of approximately 25 mm measured along the longitudinal axis.

8. The cleaning device of claim 7, wherein the first plurality of filaments is attached to the twisted steel wire over a length of approximately 15 mm.

9. The cleaning device of any one of the preceding claims, wherein the brush portion of the core column of the brush element overlaps with the proximal end portion of the core column of the brush element, such that the first plurality of filaments is attached to the twisted steel wire of the core column over an entirety of the brush portion and the proximal end portion.

10. The cleaning device of any one of the preceding claims, wherein a distribution density of the filaments of the first plurality of filaments at the brush portion is in a range of 40 to 400 filaments per unit length L.

11. The cleaning device of any one of the preceding claims, wherein a distribution density of the filaments of the first plurality of filaments at the brush portion is in a range of 100 to 120 filaments per unit length L.

12. The cleaning device of any one of the preceding claims, wherein a thickness of each individual filament of the first plurality of filaments is in a range of 0.04 mm to 0.20 mm.

13. The cleaning device of any one of the preceding claims, wherein a thickness of each individual filament of the first plurality of filaments is in a range of approximately 0.064 mm to 0.076 mm.

14. The cleaning device of any one of the preceding claims, wherein a handle element is fixedly attached to the brush element.

15. The cleaning device of any one of the preceding claims, wherein the proximal end portion of the core column comprises a protective means adapted for protection of oesophageal tissue of a user.

16. A method for manufacturing a cleaning device according to any one of claims 1-15, comprising the steps of:- (a) providing a brush element comprising a core column of twisted steel wire comprising a proximal end portion, a distal end portion, and a brush portion, and comprising a first plurality of individual filaments extending radially from the brush portion of the core column;- (b) providing a fixture comprising a rotational symmetrical hole which comprises at least a first longitudinal segment having a diameter which is less than a largest width of the brush element;- (c) inserting at least the brush portion of the core column of the brush element into the first longitudinal segment of the rotational symmetrical hole of the fixture so that the proximal end portion of the core column enters the hole first, thereby causing at least one of the two opposing end portions of each individualfilament of the first plurality of filaments to flex and form a bristle pointing in the direction of the distal end portion of the core column;- (d) placing the fixture with the at least partially inserted brush element in an oven at a temperature in a range of 170-200°C for a period of 10-30 minutes;- (e) removing the fixture with the at least partially inserted brush element from the oven and allowing the fixture to cool;- (f) removing the brush element from the fixture by pulling it out of the fixture with the distal end portion of the core column exiting first, and, optionally;- (g) attaching a protective means to the proximal end portion of the core column of the brush element, and / or, optionally;- (h) attaching a handle element to the brush element.

17. The method according to claim 16, wherein step (d) includes placing the fixture in the oven at a temperature of 180°C.

18. The method according to any one of claims 16 or 17, wherein step (d) includes placing the fixture in the oven for a period of approximately 20 minutes.

19. The method according to any one of claims 16, 17, or 18, further comprising a step (d-sub) coinciding with step (d) comprising providing a source for blowing hot air into and / or around the fixture containing the brush element to reduce the time it takes to reach the curing temperature in the center of the fixture.

20. The method according to any one of claims 16, 17, 18, or 19, wherein a length of the first longitudinal segment of the rotational symmetrical hole of the fixture is longer than a length of the brush element in its entirety.

21. The method according to any one of claims 16, 17, 18, 19, or 20, wherein the rotational symmetrical hole of the fixture comprises two or more additional segments, each additional segment having a diameter dimension and a length dimension being different from the diameter dimension and the length dimension of the first longitudinal segment.

22. The method according to any one of claims 16-21, wherein the diameter of the at least first segment of the rotational symmetrical hole of the fixture is in a range of approximately 2.3 mm - 5.3 mm.

23. The method according to claim 22, wherein the diameter of the at least first segment of the rotational symmetrical hole of the fixture is in a range of approximately 3.5 mm - 5.0 mm.

24. The method according to any one of claims 16-23, wherein the diameter of the at least first segment of the rotational symmetrical hole of the fixture is 4.2mm.

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