WO2013014172A2

WO2013014172A2 - Mouth guard

Info

Publication number: WO2013014172A2
Application number: PCT/EP2012/064544
Authority: WO
Inventors: Garrit Koller; Timothy Watson; Richard Cook
Original assignee: Kings College London
Priority date: 2011-07-28
Filing date: 2012-07-24
Publication date: 2013-01-31
Also published as: WO2013014172A3; GB201113041D0

Abstract

An oral device for delivery of fluid to the mouth having a teeth engagement element and a fluid delivery conduit for the flow of fluid or receipt of a fluid delivery tube, which is formed about the periphery of the teeth engagement element and is capable of delivery of fluid to one or more outlets to pre-determined locations in the mouth is formed such that when not in use in a user's mouth the fluid delivery conduit is readily accessible for cleaning. Effective treatment of dry mouth syndrome can be achieved whilst allowing for conduits and cavities to be readily accessed for cleaning thus providing a more hygienic oral device for fluid delivery.

Description

Mouth Guard

FIELD OF THE INVENTION

This invention pertains generally to the field of clinical dry mouth (such as dry mouth syndrome and drug-induced dry mouth) and to methods and devices of treating or preventing dry mouth. More particularly, the invention relates to a device and method for delivering fluid to the mouth.

BACKGROUND OF THE INVENTION

Dry mouth syndrome, or xerostomia, is a symptomatic condition of insufficient salivation in the mouth. The cause of dry mouth symptom can be an underlying medical condition (or its treatment), such as the autoimmune disease Sjogren's syndrome, diabetes, Alzheimer's disease, stroke, anxiety disorders and depression, or damage to the saliva glands in the mouth as is common in patients having received radiation therapy to the head or neck region or surgery, or temporary malfunction of the salivary glands as a side-effect of certain therapeutic treatments, such as some medications, for example (but not exclusively) for the treatment of depression and anxiety, antihistamines, high blood pressure medications, anti-diarrhoeals, muscle relaxants, drugs for urinary incontinence, Parkinson's disease medications and cancer chemotherapeutics. Thus dry mouth syndrome is a particular problem among oncology patient populations.

Patients with persistent dry mouth syndrome suffer severe discomfort, including a feeling of thirst and the development of a burning or scalding sensation. Secondary issues include interrupted sleep and tertiary issues associated with that, dental hygiene problems (such as increased dental caries, periodontal disease and oral infections, especially candidiasis), halitosis, difficulty with swallowing, acid reflux, sensitivity to certain foods, such as acidic, salty and spicy foods.

Efforts at treating the symptoms of dry mouth syndrome include devices for the delivery of fluid to the mouth and formulations for delivery to the mouth to treat the symptoms of dry mouth and/or mimic saliva. US2007/0204867 describes a device for controlled flow of fluid to the mouth, which comprises a reservoir, tubing and a mouthpiece, where the mouthpiece is configured to fit over the user's upper or lower frontal teeth and held in place by closure of the mouth, and defines an open arcuate channel. In use fluid is delivered into the channel at the front of the mouth and may escape from apertures positioned in a cross-member surface and/or by seeping from the arcuate channel past the teeth. Typically, the mouthpiece is pre-formed, but it may be made from a mould made to the user's specification. There is no disclosure of a separate channel for the passage of fluid than that for accommodating the user's dentures. Further, the fluid is delivered to a location close to the front of the mouth, which is less beneficial.

US2008/0161750 is concerned with an oral fluid delivery device which comprises a reservoir or source, tubing to the mouth and an oral insert. The oral insert primarily takes the form of an insert for engaging with the upper palate of the mouth to be held in place with the tongue or by being of such a size as to occupy a substantial portion of the oral cavity. It is held in place by a bite on the portion feeding into the mouth. There is an embodiment that comprises an insert configured to fit in the space between the gum/teeth and the cheek.

WO-A-2009/078024 describes an adaptation of a reservoir for use with an oral fluid delivery device, which reservoir is adapted with a spring device for controlled pressurisation of fluid. Multiple embodiments for delivering fluid from the reservoir are described.

US2008/0272153 discloses a mouthpiece comprising a mouth guard adapted to have a coupler in the form of a tube receiving aperture on the peripheral surface. The aperture, in the form of a tubular conduit, is adapted to receive tubing, which may be tied at the end to retain it in position. The distal end of the tubing may be provided with an aperture to allow fluid to seep or pump into the mouth. However, the coupler appears to be such that supply tubes are

unrestrained and would be irritating to the user and easily bitten themselves, thus reducing fluid flow and causing discomfort. Further, the coupler apertures provide a location for bacterial growth, which is inaccessible to clean. One problem with existing oral devices for delivery of fluid for the symptoms of dry mouth is the effectiveness of fluid delivery to the mouth. Another potential problem and concern among users of mouth guards and other oral devices adapted for delivery of fluid is hygiene associated with the mouthguard. Hygiene is a particular problem and concern for those patient groups having compromised immune systems, e.g. those whose xerostomia stems from radiation therapy or surgery or from ongoing chemotherapy. Devices which have the potential to harbour bacteria represent a health risk in such patients.

The prior art devices do not provide effective and efficient delivery of fluid to the mouth whilst addressing the problems associated with hygiene and risk of bacterial infection.

The present inventors have found that a new design of oral device for the delivery of fluid to the mouth allows them to overcome or address the above problems.

PROBLEM TO BE SOLVED BY THE INVENTION

There remains a need for improvements in fluid delivery to the mouth for the treatment of symptoms of dry mouth syndrome.

It is an object of this invention to provide a device for enabling fluid to be delivered and appropriately distributed in the mouth.

It is a further object of the invention to provide such a device that is readily cleaned and which does not represent an unnecessary health risk for users with compromised immune systems.

It is a further object of the invention to provide a mould blank configured to form a device for delivery of fluid shaped for fitting to an individual user.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the invention, there is provided an oral device for delivery of fluid to the mouth, the device comprising a teeth engagement element for engagement with the upper and/or lower teeth of a user and comprising a fluid delivery conduit for the flow of fluid or receipt of a fluid delivery tube, the fluid delivery conduit being formed about a periphery of the teeth engagement element and which fluid delivery conduit is, in use, capable of delivery of fluid to one or more outlets via which fluid may be delivered to one or more pre- determined locations in the mouth, wherein, extra-corporeally, the fluid delivery conduit may be exposed and accessed for cleaning.

In a second aspect of the invention, there is provided an oral device blank for forming an oral device as defined above for fitting an individual user.

In a third aspect of the invention, there is provided a fluid delivery system for delivery of fluid to the mouth, the system comprising a fluid reservoir, an oral device as defined above and a supply connector for connecting the fluid reservoir to the oral device.

In a fourth aspect of the invention, there is provided a method of delivering fluid to the mouth, the method comprising providing an oral device as defined above and fitting same into a user's mouth, connecting to the oral device a fluid reservoir via a fluid supply line such that fluid communication is achieved and causing fluid to flow from the fluid reservoir through the fluid supply line into the oral device and from the oral device into the mouth according to a pre-determined regimen and/or on demand of the user.

In a fifth aspect of the invention, there is provided a method for the treatment or prevention of dry mouth syndrome or symptoms thereof, the method comprising the steps of providing to a patient in need thereof an oral device as define above, and administering to the patient via the oral device a mouth wetting or lubricating fluid.

In a sixth aspect of the invention, there is provided a method of manufacturing an oral device as defined above.

ADVANTAGES OF THE INVENTION

The device of the present invention enables fluid to be delivered effectively to the mouth of a sufferer of dry mouth syndrome securely distributing the fluid to a chosen position in the mouth for most effective wetting whilst allowing for conduits and cavities to be readily accessed for cleaning. Thus a more hygienic oral device for fluid delivery is provided which is suitable for use by patients having dry mouth who have compromised immune systems, such as oncology patients.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a plan view of an oral device of one embodiment of the fitted onto a mould of a set of teeth; and

Figure 2 is a diagrammatic representation of a cross section through a posterior portion of the device of the embodiment of Figure 1.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides for an improved oral device for the delivery of fluid to the mouth of a user for the treatment of symptoms of dry mouth. The oral device according to the present invention comprises a teeth engaging element, for engagement with the upper or lower teeth (which may be the teeth, gums (in the absence of teeth) or dentures) and which comprises a fluid delivery conduit for the flow of fluid or receipt of a fluid delivery tube, which fluid delivery conduit is capable of delivery of fluid to one or more outlets via which fluid may be delivered to one or more pre-determined locations in the mouth. The fluid delivery conduit is formed about a periphery of the teeth engagement element, whereby the conduit does not interrupt or inconvenience the bite of the user.

The oral device of the invention provides the particular benefit that when outside the mouth, the interior of the fluid delivery conduit, whether it is configured for flow of fluid or for receipt of a fluid delivery tube, may be exposed and accessed for cleaning. This benefit is particularly important as unexposed areas in mouthguards or other oral devices, such as apertures for receiving tubing or for fluid containment, are ideal for biofilm development and microbial growth. This is a potentially serious problem for patient groups, such as oncology patients (who represent a signification proportion of sufferers of xerostomia), whose immune systems are compromised. The oral device of the invention may be defined as having an interior or internal surface, being that side or surface of the device in engagement (or adapted for engagement) with the teeth, and an exterior or external surface, being that side or surface that is not engaged (or not adapted for engagement) with the teeth. Preferably, the fluid delivery conduit may be exposed and accessed from the internal surface of the oral device.

Preferably, the teeth engagement element comprises at least a facial portion adapted for engagement with the facial surfaces of the teeth and/or a lingual portion adapted for engagement with the lingual surfaces of the teeth and, more preferably, also a bite portion adapted for engagement with the occlusal and/or incisal surfaces of the teeth.

Preferably, the teeth engagement element comprises at least a facial portion adapted for engagement with the facial surfaces of the teeth and a bite portion adapted for engagement with the occlusal and/or incisal surfaces of the teeth and wherein the fluid delivery conduit is formed proximal to the junction between the facial portion and the bite portion of the teeth engagement element. The fluid delivery conduit may thus preferably be accessed for cleaning via an interior surface of the device, enhanced by parting the facial and bite portions of the teeth engagement element. Preferably, the fluid delivery conduit, which is preferably formed proximal to the junction of a facial portion and a bite portion of the teeth engagement element about the periphery thereof, is of substantially tubular shape and in cross-section is a substantially circular protrusion from the junction of a facial portion and a bite portion of the teeth engagement element providing an unbroken connection on the external surface of the device between the facial portion and the bite portion. On the internal surface of the device between the junction of the facial portion and the bite portion, in cross-sectional view, the circumference of the circular protrusion forming the fluid delivery conduit is broken (by which it is meant the circular protrusion is not continuous in a material sense, although it may be continuous by virtue of abutment of the facial and bite portions). Accordingly, in this preferred embodiment the break in the circumference of the protrusion forming the fluid delivery conduit defines a crevice, along the extent of the fluid delivery conduit, accessible from the in internal surface of the oral device, typically between the facial and bite surfaces of the teeth engagement element. In use, the width of the crevice (and thus the size of the break in circumference of the circular protrusion) may be limited according to the embodiment of the invention utilised. With reference to two preferred embodiments of the invention: according to a first, in which the fluid delivery conduit itself carries fluid to be dispersed in the mouth, the crevice is substantially absent due to abutment of a shoulder of the facial portion (being a shoulder formed or defined as that point on the internal surface of the device where the facial portion meets the fluid delivery conduit) and a shoulder of the bite portion (being a shoulder formed or defined as that point on the internal surface of the device where the bite portion meets the fluid delivery conduit), whereby fluid seepage through the crevice is low and/or substantially minimised; and according to a second, in which the fluid delivery conduit receives a further integral fluid delivery tube whereby the size of the crevice is of lesser consequence and is preferably minimised to a level that minimises movement of the tube that it receives.

Optionally, the crevice may be minimised during use by a closure element which may be of any suitable form and which may be engaged prior to fitting into the user's mouth. However, more preferably, there is no closure element as such as typically this provides locations for stagnation of water, growth of biofilm and bacteria and are troublesome to clean. It would also complicate manufacturing somewhat.

Preferably, the fluid delivery conduit is generally integrally formed with the teeth engagement element, by which it is meant that the oral device is formed of a single piece mould as and between the teeth engagement element and the fluid delivery conduit.

Preferably, to the peripheral extent of the fluid delivery conduit, the facial portion and the bite portion of the teeth engagement element are joined only by the material defining the fluid delivery channel.

In one preferred embodiment, the teeth engagement element comprises a lingual portion adapted for engagement with the lingual surfaces of the teeth, preferably in addition to the facial and bite portions. In this preferred embodiment, the device comprises a teeth engagement element having a facial portion, a bite portion and a lingual portion which together engage the teeth of the user. The facial, bite and lingual portions together define a channel of a generally U-shape in section, typically a flattened U-shape, in which channel the teeth of a user may be received in engagement of the user's teeth. The interior surface of the channel may, of course, be moulded to the individual user's teeth.

Optionally, according to one application of this embodiment, the fluid delivery conduit may be configured to be formed in association with the lingual portion of the teeth engagement element (e.g. at the junction of the lingual portion and the bite portion or along a palatal edge of the lingual portion of the teeth engagement element). To this extent, the fluid delivery conduit may be said to extend along a lingual surface. The conduit may be arranged to feed to the lingual surface of the teeth engagement element in any suitable way, e.g. via a gap in the teeth. Preferably, however, in this embodiment, in order to deliver fluid to the lingual surface of the teeth or to the tongue or area of the mouth within the boundary of the dentition, the conduit may extend along the periphery of the teeth engagement element and form a return whereby in use it may pass around the back of the teeth engagement element (which in use will preferably allow the conduit to pass around the back of the dentition) and extend along the lingual surface of the teeth engagement element. The fluid delivery conduit in this embodiment may then be configured to deliver fluid to any one or more locations about the periphery of the teeth engagement element and/or along the lingual surface of the teeth engagement element.

The oral device of the present invention may be of a size and fit to provide a teeth engagement element of various configurations as may be desired. For example, the teeth engagement element may be configured for engaging with just molar and premolar teeth on one side of the mouth (for which facial, bite and lingual portions would certainly be required) or for engaging with incisors and molars on one side of the mouth, whereby fluid delivery to one side of the mouth may be provided. Alternatively, the teeth engagement element may be such as to provide engagement with premolars and molars on each side of the mouth (on the upper or lower teeth) whilst having only a facial portion or a lingual portion about the incisors. Alternatively, and more preferably, the teeth engagement portion is configured to engage with front and back teeth at each side of the mouth on the upper or lower set.

Preferably, the device is of a generally U-shaped form corresponding to the outline of the upper or lower set of teeth. Preferably, the teeth engagement portion is configured to engage with the incisors and the premolars and at least one molar and optionally the full upper or lower set of teeth (which may be referred to herein as dentitions).

Preferably, the device of the invention is configured such that the fluid delivery conduit extends about the periphery of the teeth engagement element from an incisor portion to a molar portion thereof on one or both sides, preferably on both sides.

The fluid delivery conduit typically comprises an inlet aperture for receiving fluid or a fluid delivery tube which inlet aperture is preferably provided proximal to a labial portion of the teeth engaging element, preferably on the mesial surface thereof.

The fluid delivery conduit typically comprises one or more outlet apertures which may be configured to allow fluid to be delivered from the fluid delivery conduit to various positions in the mouth or may be aligned with outlets provided in a fluid delivery tube to be received in the fluid delivery conduit.

As mentioned above, the oral device of the invention may be configured for use on the upper teeth or on the lower teeth. Optionally, a user may use a device adapted for use with the upper teeth and a device for use on the lower teeth. However, it is expected that only one device would be used at a time. As a further option, the device may be configured for use on both the upper and lower teeth. Preferably, the device is configured for use on the upper teeth only.

According to this embodiment, the inlet aperture may be configured to be associated with the mid or apex part of the incisors preferably at or about the medial line. As mentioned above, the fluid delivery conduit may perform the function itself of carriage of fluid to outlets for delivering and/or dispersing fluid to the mouth or it may merely be used to received and retain a fluid delivery tube through which fluid is delivered to the mouth.

In one embodiment of the invention, where the fluid delivery conduit is adapted to contain and deliver fluid, the delivery conduit is preferably adapted such that in the mouth the crevice on the internal surface of the device between the bite portion and the facial portion is substantially occluded, typically by the configuration of the element, whereby it is capable of substantially containing and/or distributing fluid from an inlet aperture to one or more outlet apertures, at least one of which is preferably located proximal the first and/or second molar of a user. Optionally, the device comprises a closure element by which the crevice may be secured and/or sealed closed, but preferably there is no such closure element. A device according to this embodiment preferably comprises an inlet aperture which comprises a connector for connecting a fluid supply line for supplying fluid from, for example, a reservoir of fluid, to the fluid delivery conduit. Once connected, the fluid supply line is typically in fluid communication with the fluid delivery conduit, whereby fluid may pass through the fluid supply line, through the inlet aperture of the fluid delivery conduit, through the delivery conduit and through the outlets. Optionally, the inlet aperture or the fluid supply line has associated with it a valve, whereby fluid communication is achieved on opening of such a valve. Typically, in an embodiment where the oral device is generally U- shaped and serves fluid delivery to each side of the mouth, a single fluid delivery conduit is provided which serves both sides of the mouth and is supplied by a single fluid supply line to a single inlet aperture. However, in an alternative embodiment in which the oral device is generally U-shaped an service fluid delivery to each side of the mouth, the fluid delivery conduit may be configured such that each side of the mouth is served by a separate fluid delivery conduit, each separated by a partition associated with the fluid inlet and wherein a fluid supply line is provided to supply fluid to both fluid delivery conduits or two fluid supply lines are provided, each to supply fluid to one of the fluid delivery conduits. This latter embodiment may be beneficial, for example, where a patient is sleeping on its side so as to ensure an equal distribution of fluid to each side of the mouth.

In a second embodiment of the invention, where the fluid delivery conduit is adapted to receive a fluid delivery tube, itself for the carriage and delivery of fluid, the conduit may be adapted to be capable of receiving the fluid delivery tube, but need not be capable of containing and delivering fluid in itself. The fluid delivery conduit preferably is capable of receiving and retaining a fluid delivery tube, which may be typically a catheter tubing material capable of passage of fluid, which fluid delivery tube is preferably provided with one or more outlet apertures for distribution of fluid in the mouth. Preferably, the fluid delivery conduit is provided with outlet aperture corresponding to those of the fluid delivery tube.

In either embodiment, and according to the device of the invention in general and other embodiments thereof, the device is preferably configured to distribute fluid to one or a plurality of locations in the mouth according to the location of outlet apertures in the fluid delivery conduit and (where appropriate) outlet apertures in a fluid delivery tube contained in the conduit. For example, the device may be configured to deliver fluid to one or more locations such as along the periphery (e.g. the facial surface) of the dentition (or set of teeth) at locations proximal the incisors and/or the canines, to the premolars or locations proximal the first and/or second and/or third molars, at the back of the dentition, and/or to locations along the lingual surface of the teeth (i.e. lingual side of the dentition) such as proximal to the first and/or second and/or third molars, to the premolars or at locations proximal the canines and/or the incisors. In each case, the device may be configured to deliver fluid in any one or more directions from the conduit according to the orientation of apertures therein (e.g. toward the teeth, or according to the location of the apertures toward the cheek or tongue). Preferably, the device is configured to deliver fluid at least to a location proximal to the first and second molars, optionally between the first and second molars. The first and second molars are adjacent to the primary saliva gland in the mouth, the parotid saliva gland. Without being bound by theory, it is believed that delivering fluid to a location proximal the parotid saliva gland, maximum benefit from the natural fluid dynamics and contours of the mouth can be achieved. Preferably, therefore, the device is adapted to deliver fluid to the mid-buccal region wherefrom effective distribution about the mouth can be achieved.

Optionally, the oral device of the present invention may be configured as useable by any user, e.g. ready-to-use, in which the teeth engaging element is of a generalised shape. Optionally, the teeth engaging element can be configured to be of one of a range of sizes according to the range of patient requirement. Optionally, the oral device may be formed to fit a particular user, e.g. by taking a mould of the user's teeth and manufacturing the device to the mould.

Alternatively, and preferably, the device of the invention may be formable (or fabricated) from a thermally formable blank to fit an individual user. In this preferred form, which is otherwise known as a boil-in-the-bag device, the oral device may be formed according to a generally U-shaped configuration, having a pre-formed and pre-shaped external surface in which the external surfaces (e.g. the external surface of the bite portion and of the facial portion) of the device and the fluid delivery conduit are formed of a material that is not readily mouldable and conformable by the user, whereas the internal surface of the teeth engagement element, which define a channel for receiving the teeth of the user, may be formed of a mouldable or conformable material, e.g. a thermoplastic material, whereby the device may be conformed for use by the user by heating the device and biting onto the device, without detriment to the shape and configuration of the fluid delivery conduit and without detriment to the access provided to the fluid delivery conduit from the internal surface of the device.

According to a further aspect of the invention, there is provided an oral device blank for use in forming an oral device as defined above. Preferably, the oral device blank may be pliable (thermally or otherwise) to enable it to be user mouldable to form an oral device for the delivery of fluid as defined above.

Preferably, the oral device blank according to this aspect comprises a teeth engagement element which may be moulded or conformed for engagement with an individual user's teeth, which teeth engagement element comprises at least a bite portion and a facial portion as defined above and which oral device blank further comprises a fluid delivery conduit for the flow of fluid or receipt of a fluid delivery tube, the fluid delivery conduit being formed about the periphery of the teeth engagement element and preferably proximal to the bite and facial portions of the teeth engagement element and which fluid delivery conduit is, in use, capable of delivery of fluid to one or more outlets via which fluid may be delivered to one or more pre-determined locations in the mouth, wherein, extra-corporeally, the fluid delivery conduit may be exposed and accessed for cleaning. Preferably, the oral device blank of this aspect comprises a non-mouldable portion, which may be referred to as a base portion, which preferably comprises at least an external portion or layer of a bite portion of the teeth engagement element, which includes the external surface of the bite portion, at least part of an external portion or layer of a facial portion of the teeth engagement element, which includes at least a part of the external surface of the bite portion, and the fluid delivery conduit.

Accordingly, during a user-conforming process, the integrity of the shape of the device and the integrity of the fluid delivery conduit and its relationship with the bite and facial portions of the teeth engaging element may remain. Preferably, any facial portion shoulder and/or bite portion shoulder form part of the non- conformable or base portion. Preferably, the oral device blank comprises a mouldable or conformable portion, which preferably includes the remainder of the teeth engagement element (other than that forming the non-mouldable portion) and in any case preferably comprises at least an internal portion of the bite portion or layer of the teeth engagement element, which includes at least an internal surface of the bite portion, and an internal portion or layer of the facial portion of the teeth engagement element, which includes at least an internal surface of the facial portion, and, where present, at least an internal portion or layer of a lingual portion of the teeth engagement element, which includes at least an internal surface of the lingual portion. Accordingly, a user may adapt the internal surface of the teeth engagement element to the shape and conformation of their teeth without disrupting the overall shape of the device or the integrity of the fluid delivery conduit or its relationship with the bite and facial portions of the teeth engagement element.

The conformable or mouldable oral device blank may take any suitable form. Two embodiments of such a device blank are envisaged. In a first embodiment of an oral device blank, the non-mouldable portion or base portion is formed of a non-thermoplastic material, by which it is meant a material that is not thermoplastic at a temperature of 100°C or less, whilst the mouldable portion is formed of a thermoplastic material, by which it is meant a material that is thermoplastic at 100°C or less and which is substantially non conformable at room temperature and at body temperature (e.g. at a temperature of 45°C or less). In a second embodiment of an oral device blank, the non-mouldable portion or base portion is formed of a pre-cured polymer material which is non-conformable and non-thermoplastic material, by which it is meant a material that is not thermoplastic at a temperature of 100°C or less, whilst the mouldable or conformable portion comprises a pliable curable polymer resin in a flexible outer membrane, which pliable curable polymer resin may be shaped to a desired shape (e.g. by a user biting on it) and cured to retain that shape.

The oral device of the present invention may be formed of any suitable material or combination of materials. For example, the device may be formed of a non-conformable or non-thermoplastic material, such as polycarbonate or polyethylene (e.g. HDPE) or polyurethane or polypropylene. In the

embodiment of the device which is thermally mouldable (i.e. boil-in-the-bag type devices), there is preferably a base portion which may comprise a non- thermoplastic polymer and a mouldable or conformable portion which comprises a thermoplastic polymer. The base portion may be comprised of, for example, any one or combination of polyethylene (e.g. HDPE), polyurethane, polypropylene or polycarbonate and optionally a thermoplastic polymer in an amount of up to 25% by weight, preferably up to 10% by weight, and still more preferably in the range 4 to 8% by weight in order to give the base portion a degree of pliability for improved comfort in the mouth, the thermoplastic polymer being optionally selected from those thermoplastic material mentioned elsewhere herein. The mouldable or conformable portion of such an embodiment, may be selected from, for example, any suitable thermoplastic polymer material which is thermoplastic at 100°C or less and preferably is pliable at a temperature of no less than 40°C, more preferably no less than 45°C and still more preferably no less than 50°C. The thermoplastic polymer material may be any suitable polymer or copolymer and most preferably comprises or consists of poly ethylene vinyl acetate (poly EVA) or a soft impressionable low density polyethylene such as that described in US-A- 2002/0144686.

In another embodiment described above in which the mouldable portion comprises a pliable and curable resin, the base portion may comprise a non- thermoplastic polymer such as those mentioned above or a cured resin, whereas the mouldable or conformable portion may be formed of a curable resin in a polymer membrane. The curable resin may be, for example, a curable elastomeric rubber such as a curable silicone resin, a curable polyurethane resin, curable epoxy resin, curable polyacrylic resin or a curable polymethacrylic resin. Typically, the formulation comprises a two part formulation including the curable resin and the curing agent. Optionally, the curable resin may be UV curable or heat curable, preferably the latter. The polymer membrane may be any suitable material that is suitable for use with the curable resin, e.g. polyethylene.

In the embodiment in which a fluid delivery tube is used, it is preferably formed of a medical grade polymer as typically used in catheters, e.g. silicone rubber or latex.

Preferably, the materials used are medical grade materials or food grade materials.

Optionally, the oral device of the present invention and embodiments thereof described herein may be provided with an antimicrobial or antibacterial function, e.g. by way of a coating of an antibacterial formulation or impregnated with an antibacterial component. In one embodiment, for example, the oral device is provided with a silver-based antimicrobial (e.g. within the conduit), preferably as a surface coating or impregnated into the material of the device. The silver-based antimicrobial may comprise polymer-stabilised silver nano-particles. Optionally the silver based antimicrobial may be one of several known in the art suitable for impregnation into or coating onto the oral device of the present invention, e.g. that available commercially as ComfortCoat™ from DSM Biomedical.

The oral device of the present invention is, as is mentioned above, typically supplied by a fluid supply line from a fluid reservoir. Accordingly, there is further provided as a further aspect of the invention a fluid delivery system for the delivery of fluid to the mouth of a user, the system comprising an oral device as defined above, a fluid reservoir for containing a fluid to be supplied to or via the oral device and at least one fluid supply line for supplying fluid to the oral device from the fluid reservoir. Optionally, the system further comprises a propulsion component for propelling fluid from the fluid reservoir to the oral device.

Any suitable reservoir may be provided. For example, the reservoir may be a rigid container, a syringe or piston-type container or a flexible bladder type container. Optionally, the reservoir comprises a fluid in a flexible bladder container, which is preferably adapted to be worn by a user so that the length of a supply line tubing is as short as possible (to reduce the feeling of being tied to an external device). For example the flexible bladder container may be adapted for incorporation into an article of clothing and thus may be for example: a bladder sack, which may be of a ruck sack configuration comprising a flexible bladder; or a bladder hat, which comprises a bladder formed of a material in the shape of a hat (and optionally attached to or sewn into a hat), which may optionally have a chinstrap (to which a supply line may be associated); or a bladder mask, which comprises a bladder element configured for fitting to the chin of the user, but not covering the mouth or nose, and typically held in place with a strap about the back and/or top of the head. According to this embodiment, a supply line may feed from a bladder outlet just below the mouth the inlet aperture of an oral device, which supply line may be, for example, up to about 5 cm in length. According to any of these worn bladder embodiments, it is possible for the supply line to be 30 cm or less in length, more preferably 20 cm or less and still more preferably 10 cm or less. In any case, the reservoir container preferably is sized to hold a volume of fluid of up to 1 litre, preferably up to 750 ml, preferably at least 5 ml or at least 10 ml, more preferably at least 100 ml e.g. in the range 250-750 ml.

Propulsion of fluid may be by any suitable means. Of three embodiments envisaged, the propulsion of fluid may be achieved according to a first embodiment by a mechanical or electromechanical propulsion component, such as a pump, according to a second embodiment by a gravity feed, or according to a third embodiment fluid propulsion may be suction-driven.

According to the third propulsion embodiment, where the propulsion of fluid is suction driven, the system may comprise, for example, a bladder-type reservoir connected to the oral device via a supply line and the oral device comprises a fluid delivery conduit having at least one fluid outlet, which is preferably proximal to the first and/or second molars. By positioning the outlet by the upper 1^st and 2^nd molars, it is believed that it is ideally positioned to be drawn into the mouth by natural sucking action, in a manner in which the saliva gland is naturally induced to wet. Fluid distribution may then be maximised by utilising the natural contours of the mouth and teeth which are naturally adapted to distribute fluid from the mid-buccal region. Fluid may be delivered to the patient simply by the action of the patient applying a suction action to the mouth (e.g. with the mouth closed) such as might occur naturally during the process of swallowing.

Whilst a certain degree of training may be required on the part of the user, a cycle of swallowing fluid in the mouth and inducing flow of further fluid into the mouth may be developed. Preferably, the suction-induced flow is augmented by a certain amount of positive pressure on the volume of the reservoir, such as may be achieved by the patient's weight applied to a wearable bladder reservoir whilst sleeping. This method is particularly useful as it is demand driven. In one embodiment, the inlet aperture of the oral device has a one-way valve to prevent fluid in the oral device from exiting via the inlet aperture.

According to the second embodiment, the reservoir is required to be suspended at a position above the user in order to provide a head of pressure to drive fluid through the oral device. Such gravity driven propulsion may be augmented by user suction.

According to the first embodiment or collection of embodiments in which propulsion of fluid is provided by a mechanical or electromechanical pump, such propulsion may be achieved in many suitable ways. In one such embodiment, the reservoir comprises an outlet and a fluid compression means for compressing fluid, which fluid compressing means may be activated by engaging a resiliently compressible or resiliently stretchable member such as a coil spring. Alternatively, a drive mechanism (or mechanical pump) may be provided which is powered by a wind-up mechanism comprising a spring-coil or other such mechanism, whereby drive pressure is applied at a low level on a continuous basis for the duration of the device, e.g. over an 8-hour period. In an alternative, the propulsion mechanism is an electromechanical system driven by an electrical motor, e.g. an electrically powered pump, which may be powered, for example, by a battery. A pump may be fitted at the outlet of the fluid reservoir or anywhere along the supply line.

In another embodiment in which the propulsion of fluid is achieved by a mechanical propulsion component, the fluid may be pumped by a biting action by the user, which may be achieved if, for example, the fluid conduit is configured such that it is compressed during biting by the user. By fitting the fluid inlet of the fluid conduit with a one-way valve which allows fluid only into the oral device and by fitting the fluid outlet with a one way valve which allows fluid only out of the fluid delivery conduit, each bite has the effect of pumping an amount of fluid into the mouth. Thus, in one embodiment, the system (and oral device) is provided with a fluid delivery conduit which is configured to be compressible by a bite by the user, which fluid delivery conduit has a fluid outlet provided with a one-way valve and a fluid inlet provided with a one way valve.

Where the fluid propulsion is provided by an electomechanical pump, the system may be configured to provide a controlled and pre-determined supply of fluid continuously or over a pre-determined period. For example, the pump may be configured to deliver a continuous low-flow of fluid (e.g. from 0.1 to 5 ml per minute, preferably 0.5 to 1.5 ml per minute) and, optionally, may be configured to deliver a user-demanded bolus (e.g. from 1 ml to 10 ml, e.g. 2 ml to 5 ml) delivery of fluid, which user demand may be, for example, on depression of a button so configured.

The reservoirs described herein are provided as further aspects of the invention that are or may be adapted for use in any fluid delivery system for delivery of fluid to the mouth and/or for use in any oral fluid delivery device.

Optionally, the reservoir or supply line may be refrigerated or otherwise associated with a refrigerated coolant in order to deliver a chilled liquid to the patient. For example, the reservoir may be kept cold by recirculating a coolant through a thermally conductive coil provided in the reservoir.

Alternatively, the supply line may be passed through a reservoir of coolant.

The fluid being delivered to the mouth may be any suitable f uid and is typically a water or aqueous liquid. Typically, for the treatment of xerostomia, the f uid is an aqueous lubricating liquid as a substitute for saliva. Preferably, the fluid may contain components for providing viscosity enhancement, lubrication, re- mineralising agents, and certain enzymes and amino acids that may help mimic the effect of natural saliva (including the breakdown of foods). Optionally, an aqueous lubricating fluid as a substitute for saliva may comprise further components selected from, for example, ethylene glycol, propylene glycol, carboxymethyl cellulose, hydroxymethyl cellulose, buffering agents, and enzymes such as alpha amylase.

The fluid may be adapted to have a low viscosity for ease of delivery, e.g. for delivering along fine bore tubes from reservoir to mouth, or a high viscosity for improved adhesion in the mouth, depending upon the clinical condition being managed.

Optionally, certain commercially available saliva substitute products may be utilised, such as Salivart™, Orallube™, Xerolube™, Saliva Orthana™, Glandosane™ and Biotene™ Oral Balance Gel.

Optionally, the fluid may contain therapeutic or analgesic active compounds, such as antimicrobial compounds or other orally available drugs. Therapeutic or analgesic components may be, for example, antibiotics, anti-virals (e.g. acyclovir type preparations), antifungals (e.g. nystatin or miconazole), disinfectants (e.g. chlorhexidine) or drugs for mucosal absorption, such as cardiac dilators (e.g. glyceryl trinitrates), or tissue modulators (e.g. fluoride for mineral repair), immune-modulators for soft tissues (e.g. steroids) or immunosupressants (e.g. protopic or similar compounds).

The invention will now be described in more detail, without limitation, with reference to the accompanying Figures.

In Figure 1 , an oral device 1 in U-shaped form to generally relate to the shape of the set of teeth comprises a teeth engaging element 3, for fitting to the upper set of teeth of the user, and a fluid delivery conduit 5 is provided about the periphery thereof on each side. The fluid delivery conduit 5 extends about the periphery from the incisor portion 7 (adjacent the first incisor 9) to the molar portion 11 of the teeth engaging element 3 (adjacent the first molar 13) on each half of the device and comprises an aperture at the posterior end 15 of each delivery conduit 5 to deliver fluid to a position adjacent the first molar 13 and second molar 17, which is a position corresponding to the major saliva gland (the parotid saliva gland) of the mouth, whereby maximum benefit from the natural fluid dynamics of the mouth can be drawn. Each fluid delivery conduits 5 is adapted to receive a fluid supply tube 19 along its length via an inlet aperture 21, which fluid supply tubes 19 are typically fed fluid from one or more connected reservoirs (not shown). The teeth engaging element 3 is made up of a facial portion 23, bite portion 25 and lingual portion 27 which together form a generally flattened U- shaped section channel, which is moulded to fit the teeth of the user. Accordingly the device 1 may be held securely in the mouth whilst delivering fluid to the buccal portion of the mouth adjacent the second and third molars for maximal wetting effect.

The fluid delivery conduit 5 is formed at the junction of the bite portion 25 and the facial portion 23 of the teeth engaging element 3 about the periphery thereof and adjacent the facial surface. By providing the fluid delivery conduit at the junction of the bite and facial surfaces of the teeth engaging element 3, the device 1 worn on the upper set of teeth of the user allows the fluid delivery conduit 5 to be comfortably accommodate the delivery conduit in the spacious mid-buccal area at the sides of the mouth (rather than, for example, at a position by the gums that tends to irritate).

As can be seen in Figure 1 , the device is of unitary plastic form moulded to shape. Thus, to the extent of the fluid conduit, the bite portion and facial portion of the teeth engaging element are joined only by the material forming the fluid delivery conduit. By applying opposing pressure to the interior surface of each of the facial and bite portions when the device is disengaged from the teeth of the user, the fluid delivery conduit cavity is exposed, unoccluded for cleaning. Thus, the device may be readily and effectively cleaned minimising the risk of bacterial infection.

Figure 2 shows a cross section through the device 1 at the posterior end 15 of one of the sides thereof. U-shaped channel 29 is formed together by facial portion 23, bite portion 25 and lingual portion 27 and fluid delivery conduit 5 is shown at the junction of facial portion 23 and bite portion 25. The external surface 31 of the device 1 is continuous, by which it is meant unbroken, from facial portion 23 to fluid delivery conduit 5 to bite portion 25. On the internal surface 33, the continuity of the internal surface 33 of the facial portion 23 and that of the bite portion 25 is broken by a crevice 35 defined by a gap between facial portion shoulder 37 and bite portion shoulder 39. The crevice 35 runs along the length of the fluid delivery conduit 5 providing exposing the conduit and providing access for cleansing. The width of crevice 35 can be increased extra-corporeally by applying an outward force to separate facial portion 23 from bite portion 25 thus providing better access to clean the interior of the conduit 5. The embodiment of the device 1 shown in figure 2 is capable of receiving and retaining a fluid delivery tube (not shown). For the embodiment of the invention where the fluid delivery conduit 5 is adapted for passage of fluid, the device is formed such that in resting position in the mouth the facial portion shoulder 37 abuts the bite portion shoulder 39 thereby minimising the width of crevice 37 and occluding access to the conduit 5, which may still be accessed extracorporeally by separating the facial portion 23 and bite portions. Thus the conduit 5 may distribute fluid via outlets (not shown) formed therein.

The invention has been described with reference to a preferred embodiment. However, it will be appreciated that variations and modifications can be effected by a person of ordinary skill in the art without departing from the scope of the invention.

Claims

CLAIMS:

1. An oral device for delivery of fluid to the mouth, the device comprising a teeth engagement element for engagement with the upper or lower teeth of a user and comprising a fluid delivery conduit for the flow of fluid or receipt of a fluid delivery tube, the fluid delivery conduit being formed about a periphery of the teeth engagement element and which fluid delivery conduit is, in use, capable of delivery of fluid to one or more outlets via which fluid may be delivered to one or more predetermined locations in the mouth, wherein, extra-corporeally, the fluid delivery conduit may be exposed and accessed for cleaning.

2. An oral device as claimed in claim 1 , wherein the teeth engagement element comprises at least a facial portion adapted for engagement with the facial surfaces of the teeth and a bite portion adapted for engagement with the occlusal and/or incisal surfaces of the teeth and wherein the fluid delivery conduit is formed proximal to the junction between the facial portion and the bite portion of the teeth engagement element.

3. An oral device as claimed in claim 2, wherein the teeth engagement element comprises a lingual portion adapted for engagement with the lingual surfaces of the teeth.

4. An oral device as claimed in claim 2 or claim 3, wherein to the peripheral extent of the fluid delivery conduit the facial portion and the and the bite portion of the teeth engagement element are joined only by the material defining the fluid delivery conduit.

5. An oral device as claimed in claim 4, wherein the fluid delivery conduit may be accessed for cleaning via an interior surface of the device by parting the facial and bite portions of the teeth engagement element.

6. A device as claimed in any one of the preceding claims, wherein the device is of a substantially U-shaped form corresponding to the outline of the upper or lower set of teeth.

7. A device as claimed in any one of the preceding claims, wherein the tooth engagement element comprises a facial portion, a bite portion and a lingual portion which together define a generally U-shape sectioned channel in which the teeth of a user may be received in engagement of the user's teeth.

8. A device as claimed in any one of the preceding claims, wherein the fluid delivery conduit extends about the periphery of the teeth engagement element from an incisor portion to a molar portion thereof on one or both sides.

9. A device as claimed in any one of the preceding claims, wherein the fluid delivery conduit comprise an inlet aperture for receiving fluid or a fluid delivery tube which inlet aperture is provided proximal to a labial portion of the teeth engaging element, preferably on the mesial surface thereof.

10. A device as claimed in any one of the preceding claims, wherein the fluid delivery conduit comprises an outlet aperture proximal for the first and/or second molar of the user.

11. A device as claimed in any one of the preceding claims which is thermally formable from a blank for fitting to an individual user.

12. An oral device blank for use in forming an oral device as claimed in claim 11.

13. An oral device or oral device blank as claimed in any one of the preceding claims, which comprises a base portion of non-thermoplastic material and a mouldable or conformable portion of thermoplastic material.

14. An oral device as claimed in any one of the preceding claims, wherein the fluid delivery conduit is extends from the incisors to the molars and is adapted to receive a fluid delivery tube along its length through an inlet aperture at the labial portion of the teeth engagement element, which fluid delivery tube is retained within the fluid delivery conduit and which fluid delivery tube has one or more apertures associated with outlets of the fluid delivery conduit.

15. A fluid delivery system for delivery of fluid to the mouth, the system comprising a fluid reservoir, an oral device as claimed in any one of claims 1 to 11 and a supply connector for connecting the fluid reservoir to the oral device.

16. An oral device, an oral device blank or a fluid delivery system as hereinbefore described with reference to the drawings.