Patent Publication Number: US-2021169624-A1

Title: Oral Care Device with Sacrificial Electrode

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a divisional of U.S. patent application Ser. No. 16/215,236, filed Dec. 10, 2018, which is a continuation of U.S. patent application Ser. No. 14/983,724, filed Dec. 30, 2015, now U.S. Pat. No. 10,179,038, the entireties of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     Various oral care implements, such as toothbrushes, dental trays, and dental strips, are conventionally known. Such implements often act as a carrier for a dentifrice, which may be provided as a paste, gel, powder, liquid or some other composition. It is also conventionally known to provide one or more active ingredients in the dentifrice to achieve different oral health benefits. For example, conventional dentifrices may include ingredients that freshen breath, others that enhance tooth whitening, and/or still others that kill bacteria. However, it would be desirable to provide an oral care implement that can provide oral health benefits in addition to the separate dentifrice or without the requirement for the separate dentifrice. 
     Accordingly, there is a need in the art for an oral care implement that provides oral health benefits without or in addition to a dentifrice solution. 
     For example, there is a need in the art for an oral care implement that can generate ions in the head of the toothbrush, which may be used to promote oral health from within the oral cavity. 
     BRIEF SUMMARY 
     This application describes improved oral care implements, containers, or other devices that incorporate one or more electrode pairs. Within each electrode pair, a sacrificial metal is used that breaks down when a potential difference is applied across the electrode pair. Ions are released when the metal breaks down, and those ions aid in oral health. 
     In one aspect, the invention may be a container comprising; a body adapted to contain an oral care solution; and a cap selectively removable from the body, wherein the cap comprises: a cavity configured to contain a fluid; a first electrode comprising a sacrificial metal; a second electrode spaced from the first electrode; and an electrical connection electrically connecting the first electrode and the second electrode to a power source; and wherein activation of the power source generates an electric field between the first and second electrodes, thereby causing the sacrificial metal of the first electrode to release ions into the fluid in the cavity of the cap 
     In another aspect, the invention may be an oral care device configured for placement in an oral cavity comprising: a base layer having a longitudinal axis; a power source disposed on a surface of the base layer; and an electrode layer disposed on the surface of the base layer or on a surface of the power source, the electrode layer comprising a first electrode comprising a first metallic strip electrically connected to the power source and a second electrode comprising a second metallic strip electrically connected to the power source and substantially parallel to the first metallic strip, wherein the electrode layer is disposed such that a length of the first electrode and a length of the second electrode are substantially parallel to the longitudinal axis of the base layer 
     In yet another aspect, the invention may be a toothbrush comprising: a head; a plurality of tooth cleaning elements extending from the head; a first pair of electrodes coupled to the head, the first pair of electrodes comprising a first electrode and a second electrode, at least one of the first and second electrodes being a first sacrificial electrode; a second pair of electrodes coupled to the head, the second pair of electrodes comprising a third electrode and a fourth electrode, at least one of the third and fourth electrodes being a second sacrificial electrode; a power source operably coupled to the first and second electrodes and to the third and fourth electrodes to supply a current to the first and second electrodes and to the third and fourth electrodes, thereby causing the first and second sacrificial electrodes to release ions; and wherein the first sacrificial electrode comprises a first sacrificial metal and the second sacrificial electrode comprises a second sacrificial metal 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of an oral care implement, embodied as a toothbrush, according to an example implementation of this disclosure; 
         FIG. 2  is an exploded cross-sectional view of an example implementation of the toothbrush of  FIG. 1 , taken along section line  2 - 2  in  FIG. 1 ; 
         FIG. 3  is a partial perspective view of another example implementation of the toothbrush of  FIG. 1 ; 
         FIG. 4  is a partial perspective view of another example implementation of the toothbrush of  FIG. 1 ; 
         FIG. 5  is an exploded perspective view of an oral care implement, embodied as a dental strip or patch, according to another example implementation of this disclosure; 
         FIG. 6  is a perspective view of a container for a dentifrice solution according to another example implementation of this disclosure; 
         FIG. 7  is a perspective view of a cap, such as a cap for the container illustrated in  FIG. 6 , according to an implementation of this disclosure; 
         FIG. 8  is a perspective view of a cap, such as a cap for the container illustrated in  FIG. 6 , according to another implementation of this disclosure; 
         FIG. 9  is a graph illustrating the production of zinc ions using sacrificial electrodes according to example embodiments of this disclosure; 
         FIG. 10  is a graph illustrating viability data relating to an ATP assay test, using sacrificial electrodes according to example embodiments of this disclosure; and 
         FIG. 11  is a graph illustrating viability data relating to a Resazurin assay test, using sacrificial electrodes according to example embodiments of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     This description of presently preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls. 
     This disclosure relates generally to oral care implements, and more particularly to implements configured to include electrodes connected to a power source. Some examples of the following detailed description may generally refer to embodiments of the inventive implements in the context of a toothbrush, but the disclosure is not limited to toothbrushes; other oral care implements may also incorporate features of this disclosure. By way of non-limiting example, and as will be described in some examples below, mouth guard- and tray-type oral care implements and oral strips which do not include a handle, are known, and aspects of this disclosure may be incorporated into such implements. Moreover, features of the disclosure may be incorporated into other oral health-related applications. 
       FIG. 1  illustrates a toothbrush  100  according to a first implementation of this disclosure. The toothbrush  100  generally includes a handle  102 , a head  104  disposed at the distal end of the handle  102 , and a neck portion  106  generally disposed between the handle  102  and the head  104 . As illustrated, the handle has a generally elongate shape, along a longitudinal axis. This disclosure is not limited to the shape and/or size of the toothbrush  100  illustrated in  FIG. 1 . In alternative implementations, one or more of the handle  102 , head  104 , and/or neck  106  may have different shapes, sizes, orientations, and/or the like. Additional features may also be incorporated into the toothbrush or disposed on the toothbrush. 
     In the embodiment illustrated in  FIG. 1 , the head  146  of the toothbrush  100  also includes a plurality of tooth cleaning elements  108  disposed on a tooth cleaning element support  110 . As used herein, the term “tooth cleaning elements” includes any type of structure that is commonly used for or is suitable for use in providing oral health benefits (e.g., tooth cleaning, tooth polishing, tooth whitening, massaging, stimulating, etc.) by making intimate contact with portions of the teeth and/or gums. Such tooth cleaning elements include but are not limited to tufts of bristles that can be formed to have a number of different shapes, sizes and relative configurations, massage elements, and elastomeric cleaning members that can be formed to have a number of different shapes and sizes, or a combination of both tufts of bristles and elastomeric cleaning members. The tooth cleaning elements  108  may be arranged on the tooth cleaning element support  110  in many configurations. 
     In  FIG. 1 , the tooth cleaning elements  108  include bristles, which may be formed as bristle tufts. The tufts may be formed with bristles of the same or different bristle materials (such as nylon bristles, spiral bristles, rubber bristles, etc.). Moreover, while the tooth cleaning elements  108  may be arranged so that they are generally perpendicular to a top surface  112  of the tooth cleaning element support  110 , some or all of the tooth cleaning elements may be angled with respect to that surface and/or with respect to each other. When the tooth cleaning elements  108  includes bristle tufts, it is thereby possible to select the combination of bristle configurations, bristle materials and/or bristle orientations to achieve specific intended results and operational characteristics, thus maximizing and enhancing cleaning, tooth polishing, tooth whitening, massaging, stimulation, and the like. 
     The tooth cleaning elements  108  may be attached to the tooth cleaning element support  110  by any conventional method. In certain embodiments, the tooth cleaning element support  110  may comprise a head plate having a plurality of holes formed there through, and the tooth cleaning elements may be mounted to the head plate within the holes. This type of technique for mounting the tooth cleaning elements to a head plate as the tooth cleaning element support  110  is generally known as anchor free tufting (AFT). In AFT a head plate or membrane is created and the tooth cleaning elements (such as bristles, elastomeric elements, and combinations thereof) are positioned into the head plate so as to extend through the holes of the head plate. The free ends of the tooth cleaning elements on one side of the head plate perform the cleaning function. The ends of the tooth cleaning elements on the other side of the head plate are melted together by heat to be anchored in place. As the tooth cleaning elements are melted together, a melt matte is formed, which is a layer of plastic formed from the collective ends of the tooth cleaning elements that connects the tooth cleaning elements to one another on one side of the head plate and prevents the tooth cleaning elements from being pulled through the tuft holes. 
     In some conventional designs, such as some conventional manual toothbrushes, after the tooth cleaning elements are secured to the head plate, the head plate may be secured to the head  104 , such as by ultrasonic welding. When the head plate is coupled to the head  104 , the melt matte is located between a lower surface of the head plate and a floor of a basin or cavity of the head  104  in which the head plate is disposed. The melt matte, which is coupled directly to and in fact forms a part of the tooth cleaning elements, prevents the tooth cleaning elements from being pulled through the holes in the head plate thus ensuring that the tooth cleaning elements remain attached to the head plate during use of the oral care implement. 
     In another embodiment, the tooth cleaning elements may be connected to a head plate or membrane later incorporated using a technique known in the art as AMR. In this technique, a head plate is provided and the bristles are inserted into holes in the head plate so that free/cleaning ends of the bristles extend from the front surface of the head plate and bottom ends of the bristles are adjacent to the rear surface of the head plate. After the bristles are inserted into the holes in the head plate, the bottom ends of the bristles are melted together by applying heat thereto, thereby forming a melt matte at the rear surface of the head plate. The melt matte is a thin layer of plastic that is formed by melting the bottom ends of the bristles so that the bottom ends of the bristles transition into a liquid, at which point the liquid of the bottom ends of the bristles combine together into a single layer of liquid plastic that at least partially covers the rear surface of the head plate. After the heat is no longer applied, the melted bottom ends of the bristles solidify/harden to form the melt matte/thin layer of plastic. In some conventional applications, after formation of the melt matte, a tissue cleaner is injection molded onto the rear surface of the head plate, thereby trapping the melt matte between the tissue cleaner and the rear surface of the head plate. Other structures may be coupled to the rear surface of the head plate to trap the melt matte between the rear surface of the head plate and such structure without the structure necessarily being a tissue cleaner. For example, in embodiments of this disclosure, a structure covering the melt matte may be a plastic material that is used to form a smooth rear surface of the head, or the like. In still other embodiments, the structure can be molded onto the rear surface of the head plate or snap-fit (or other mechanical coupling) to the rear surface of the head plate as desired. 
     Of course, techniques other than AFT and AMR can be used for mounting tooth cleaning elements to the tooth cleaning element surface  110 , such as widely known and used stapling/anchoring techniques or the like. In such embodiments the tooth cleaning elements may be coupled directly to the tooth cleaning element surface  110 . Furthermore, in a modified version of the AFT process discussed above, the head plate may be formed by positioning the tooth cleaning elements within a mold, and then molding the head plate around the tooth cleaning elements via an injection molding process. 
     Moreover, in certain embodiments, the invention can be practiced with various combinations of stapled, IMT, AMR, or AFT cleaning elements. Alternatively, the tooth cleaning elements could be mounted to tuft blocks or sections by extending through suitable openings in the tuft blocks so that the base of the tooth cleaning elements is mounted within or below the tuft block. In still other embodiments, likely in which the tooth cleaning elements are not bristles, the tooth cleaning elements may be molded integrally with the tooth cleaning element surface  110 . 
     A plurality of apertures  114  is also illustrated in  FIG. 1 . The apertures  114  are disposed through a sidewall  116  of the head  104  and provide a channel or passageway through the sidewall  104 . Such a channel may allow for fluid communication between an inner cavity of the head  104  of the toothbrush  100  and the external environment. The cavity, which may be bounded by the tooth cleaning element support  110 , the sidewall  104  and a base  118 , will be discussed in more detail below. 
     In some embodiments of this disclosure, an electrode system is disposed in the cavity in the head  104 . Providing electrical current to the electrode system may be useful to provide oral health benefits in addition to the benefits obtained by use of the tooth cleaning elements  108 . The electrode system may be controlled, at least in part, by a user operating the toothbrush  100 . For example, a user interface, embodied as a switch or button, may be provided on the handle  102 . 
       FIG. 2  shows an exploded, cross-section of a toothbrush  200 . The toothbrush  200  is an example implementation of the toothbrush  100 . As illustrated, the head  104  of the toothbrush  200  includes a cavity  202 . The cavity  202  is a basin or void defined by the sidewall  116  that extends upwardly from the base  118  of the head  104 . A first electrode  204  and a second electrode  206  are disposed in the cavity  202 . The electrodes  204 ,  206  may be any known shape or configuration, in addition to the configurations described in the examples herein. In the illustrated implementation, the electrodes  204 ,  206  are formed as electrical coils, and include a number of turns of a metallic wire. In the illustrated embodiment each of the electrodes  204 ,  206  includes such a winding, wound about a core  208 . The cores  208  may be formed integrally with the base or may be formed separately and subsequently fixed to the base. In other embodiments, the cores  208  may not be present at all. Electrical or conductive leads  210  connect each of the electrodes  204 ,  206  to a power source  212 . In the illustrated embodiment, the power source  212  is a plurality of batteries disposed in the handle  102  and the leads  210  extend from the electrodes  204 ,  206  through the neck  106  and into the handle  102  via a passageway or channel  214  connected to the cavity  202  of the head  104 . In some embodiments the batteries may be replaced with some other power source, and the power source may be rechargeable. 
     As also illustrated, the tooth cleaning element support  110  is positioned relative to the head  104  to cover the cavity  202 , thereby enclosing the electrodes  204 ,  206  in the cavity  202 . In some implementations, the tooth cleaning element support  110  is fixed at a distal end of the sidewall  116 , e.g., by an adhesive, welding, or other mechanical means. 
     Application of current to the electrodes  204 ,  206  creates an electrical field between the electrodes  204 ,  206 . More specifically, the electrodes may be positioned to act as an anode and a cathode. The toothbrush may also include a controller and/or additional electronics  216 . For example, the controller  216  may control current and/or voltage from the power source  212  to the electrodes  204 ,  206 . In some embodiments, the controller may alternate the current through the electrodes  204 ,  206  and/or otherwise control the current, such as through pulse width modulation or alternating the current through the coils, to achieve desired activation sequences of the electrodes  204 ,  206 . The controller  216  may also include a timing mechanism, such that the electrodes  204 ,  206  are activated for a predetermined time, for example. 
     In embodiments of this disclosure, at least one of the first electrode  204  and the second electrode  206  comprises a sacrificial electrode. A sacrificial electrode includes a sacrificial metal, and when current is applied between the first and second electrodes  204 ,  206 , the sacrificial electrode gives up ions, e.g., by oxidizing. In one presently preferred embodiment, the sacrificial electrode includes zinc and the presence of an electrical potential oxidizes the zinc to release Zn 2+ . Zinc ions are conventionally known to provide oral health benefits including e.g., anti-bacterial benefits. In this example, the zinc ions are given off in the cavity  202  of the head  104  of the toothbrush  200 . Once released from the electrode to the cavity  202 , the beneficial zinc ions enter the oral cavity via the apertures  114 . 
     The apertures  114  also allow fluids, e.g., saliva and water, in the external environment to enter the cavity  202 . Once in the cavity, the fluids act as an electrolyte to promote the release of the ions from the charged electrodes. 
     As noted above, in some embodiments the sacrificial metal may be zinc. When the electrode is a winding, as illustrated in  FIG. 2 , the wire comprising the winding may include zinc or a zinc alloy. In other embodiments, the electrodes may alternatively be formed as metal plates or other spaced-apart metal fixtures. Such other electrodes may also include zinc, zinc alloy, or some other sacrificial metal. In embodiments of this disclosure, zinc may comprise 90% or more of the metal making up the electrode, for example. 
     The description is not limited to the use of zinc and zinc alloys as the sacrificial electrode. In other implementations, for example, the sacrificial electrode may include different metals that can be oxidized to provide ions that give alternative oral benefits. For example, Tin ions, i.e., Sn2+ and Sn4+ have known oral health benefits and the sacrificial electrode could include Tin. Moreover, the oxidation of iron and/or manganese can drive the formation of hydroxide radicals from hydrogen peroxide, e.g., via the Fenton reaction, which may provide other benefits in the oral cavity. 
     Although one pair of electrodes is illustrated in  FIG. 2 , additional pairs of electrodes may also be present. For example, a first pair of electrodes may include zinc as a sacrificial metal, whereas a second pair of electrodes may include iron as a sacrificial metal. A controller such as the controller  216  may be used to individually power the pairs of electrodes, to provide varied oral care. In other implementations, multiple pairs of electrodes may include the same sacrificial metal, but the increased number will allow for release of additional ions. 
     Modifications to the toothbrush  200  described above are contemplated. For example,  FIG. 3  illustrates a toothbrush  300  having a different electrode arrangement. 
     More specifically,  FIG. 3  illustrates that the toothbrush  300  includes a head  302  defining a cavity  304 , similar to the cavity  202  described above. Four posts  306  are positioned in the cavity and extend from a bottom surface of the cavity  304 . A first electrode  310  is formed as a series of windings  312  around a pair of the posts  306 . A second electrode  314  is formed as a second series of windings  316  about the other two posts  306 . Although not illustrated in  FIG. 3 , the first electrode  310  and the second electrode  314  are electrically connected to a power source. According to the arrangement of  FIG. 3 , the elongate windings  312 ,  316  provide increased surface area over the windings about a single post. 
     The toothbrush  300  functions in substantially the same manner as toothbrush  200  described above. That is, at least one of the electrodes  310 ,  314  preferably includes a sacrificial metal, such as zinc. When a potential is applied across the electrodes, the sacrificial metal oxidizes, releasing ions into the cavity  304 . Apertures  318  are provided in the head  302  that allow for fluid flow between the cavity  304  and the external environment of the toothbrush  300 . In this manner, as in the embodiment described above, released ions may exit the head  302  and provide a benefit in the external environment, e.g., the oral cavity. The apertures  318  also allow for the flow of fluids, such as saliva and/or water into the cavity  304 , which fluids may act as an electrolyte to promote the oxidation of the sacrificial metal. 
     As also illustrated in  FIG. 3 , the toothbrush  300  may further include a barrier  320  disposed between the first electrode  310  and the second electrode  314 . The barrier  320  may be any physical structure that will prevent migration of released ions. More specifically, when a zinc sacrificial electrode is used, the barrier  320  will prevent zinc ions released from the sacrificial electrode from migrating to the other electrode. Instead, the ions will remain suspended in the electrolyte, and eventually exit the head  302  via the apertures  318  to enter the oral cavity. 
     As noted above, a benefit of the configuration of the toothbrush  300  over that of the toothbrush  200  may be that each of the electrodes of the toothbrush  300  has an increased surface area versus that of the electrodes in the toothbrush  200 . For example, in some embodiments, it may be desirable to provide each electrode with a surface area greater than about 1 cm 2  to produce sufficient ions for a desired oral benefit. For example, each electrode may be formed of 15 to 20 cm long wire having 0.25 to 0.5 mm diameter. Winding of any length of wire about two spaced posts will require fewer turns than winding about one post. As will be appreciated, the release of ions will be dependent upon a number of factors, including the surface area of the electrode, the purity of the material forming the electrode, a distance between the electrodes, and the like, and different configuration may be appropriate in different applications. 
     Other electrode configurations also are contemplated. For example,  FIG. 4  illustrates a toothbrush  400  having a cavity  404  in which a pair of electrodes  410 ,  414  is disposed. Each of the electrodes  410 ,  414  is wound about a pair of posts  406 , similar to the embodiment of  FIG. 3 . However, the wire comprising the windings  412 ,  416  of each of the electrodes  410 ,  414  is wound in a  FIG. 8  pattern. This configuration may allow for additional surface area of the electrode over the embodiment illustrated in  FIG. 3 , because it accommodates a longer length of wire in the same footprint. In each of  FIGS. 3 and 4 , the tooth cleaning elements are removed for clarity. 
     Those having ordinary skill in the art will understand that additional electrode configurations are possible. As noted above, one or both of the electrodes in an electrode pair may be formed as a metal plate or a thin metal strip, for example. 
     In some embodiments, the ions released by the electrodes may provide a direct oral care benefit, as in the case of zinc ions, which are known anti-bacterial agent. Conventionally, zinc ions have been formulated into a dentifrice or mouthwash for delivery into the oral cavity. However, aspects of the present disclosure allow for delivering free or weakly chelated zinc species directly into the oral cavity. Moreover, the zinc species may be delivered into a non-therapeutic dentifrice or mouthwash. That is, the benefits of zinc ions may be realized without the need for a specific dentifrice including the zinc. According to aspects of this disclosure, a zinc electrode may be oxidized from its metal Zn 0  state to Zn 2+  state by the removal of electrodes electrochemically: Zn→Zn 2+ +2 electrons. 
     In addition to contemplating additional electrode arrangements in a toothbrush or similar device, the inventors also contemplate the use of electrode arrangements in different oral care devices. For example,  FIG. 5  illustrates an oral care device  500  according to other implementations of this disclosure. More specifically,  FIG. 5  is a schematic illustration of a plurality of layers or substrates that are stacked or otherwise disposed together to form a complete device  500 . In embodiments of this disclosure, the device  500  is embodied as a strip or patch sized for placement in the oral cavity. The device  500  is illustrated in  FIG. 5  as having a generally rectangular shape, but this disclosure is not limited to rectangular forms. For example, the size and/or shape of the footprint of the device  500  may be varied depending upon such factors as the application, desired aesthetics, or manufacturability concerns. The strip is preferably between about 1 mm and about 5 mm thick, and more preferably about 1.5 mm to about 3 mm thick. The reduced thickness may result in more comfort for a user of the device, and may promote flexure or bending of the device, e.g., to better conform to the contours of the oral cavity. 
     As illustrated, the oral care device  500  includes a base layer  502 , a power source  504 , and an electrode layer  506 . Other layers, which may include a covering  512 , an adhesive layer  514 , and a release layer  516  also are illustrated in phantom lines in  FIG. 5 . One or more of these layers may be included in various embodiments of this disclosure. 
     The base layer  502  is preferably a thin, flexible substrate. The substrate may be made from any number of orally acceptable materials, including but not limited to, textiles, cloth, wood composite, resin, elastomer, paper, insoluble or less soluble cellulose derivatives such as ethyl cellulose and cellulose acetate, polyvinyl chloride, wax, Parafilms™, polyethylene, polyvinyl alcohol, Teflon™, polyvinyl chloride, polyvinyl acetate and their derivatives. In some instances, the flexible substrate may also or alternatively include a water-soluble polymer to promote adhesion of the device  500  to the teeth or gums. For example, the base layer  502  may include hydrophilic cellulose ethers (e.g. carboxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose), polyvinyl acetates, carbomers (e.g., Carbopol 97 IP), polysaccharide gums (e.g. xanthan gum), modified food starches, gelatin (e.g. animal or fish-based gelatin), cross-linked carboxyvinyl copolymers, cross-linked polyvinylpyrrolidones, polyethylene oxide (e.g., Polyox), polyacrylic acids and polyacrylates, polyvinyl alcohols, alginate, casein, pullulan, and combinations thereof. 
     The power source  504  is disposed on the base substrate  502 , and may be a battery. The power source may be single use or rechargeable. Although several types of batteries, including button and coin batteries, may be used in accordance with principles of this disclosure, in some preferred embodiments the power source  504  comprises a flexible power source, such as a polymer battery. Polymer batteries may be preferred for their thin profile and/or their flexibility. For instance, polymer batteries may be as thick as 750 microns, or thinner. The power source  104  may be a printed battery such as a battery commercially available from Imprint Energy, Inc. of Alameda, Calif. The printed battery may include a metal screen-printed on a flexible substrate, for example. 
     In some embodiments, the power source  504  may be adhered to the base substrate using any known adhesive, epoxy, or the like. Alternatively, the power source  504  may include the base substrate  502 . For example, some commercially available polymer batteries generally include components printed on a substrate. When such a commercially available battery is used in embodiments of this disclosure, the substrate of the battery may also act as the base substrate  502 . 
     The electrode layer  506  generally includes a pair of electrodes  508  disposed on an electrode substrate  510 . As illustrated, the electrodes  508  may be formed as two spaced-apart conductive strips functioning as an anode and a cathode with applied current. The electrodes  508  are substantially parallel and extend generally longitudinally, i.e., parallel to a longitudinal axis  518  of the device  500 . The electrodes are sufficiently thin that they can bend with, e.g., without delaminating from, the base layer  502  and the electrode substrate. The electrodes  508  may be printed or otherwise formed on the electrode substrate  510  and may comprise any number of materials including, but not limited to, tin, silver, copper, platinum, and the like. The materials comprising the electrodes preferably are chosen for their flexibility, as well as for their compatibility with the environs of the oral cavity. Also, in embodiments of this disclosure, at least one of the electrodes  508  may be formed from a sacrificial material, such as a sacrificial metal. For example, as described above, an electrode made of zinc will oxidize upon application of current, thereby releasing Zn 2+ . These zinc ions are recognized as effective anti-bacterial agents. 
     The electrodes  508  are attached to terminals of the power source  504 . In some embodiments, the electrode  508  may be connected to the power source  504  using leads or similar conductors. In still other embodiments, the electrode layer  506  may be affixed on the power source  504  in such a manner as to create an electrical communication between the electrode  508  and the power source  504 . In still other embodiments, the power source  504  and the electrodes  508  may be disposed on a common substrate, such as the base substrate  502  or the electrode substrate  510 . 
     Although two electrodes  508  are illustrated in  FIG. 1 , additional electrodes  508  may also be provided. For example, the electrodes may be positioned and numbered generally to correspond with a location and number of a user&#39;s teeth. Moreover, the electrodes may be arranged generally perpendicularly relative to the axis  516 . 
     The device  500  comprising the base substrate  502 , the power source  504 , and the electrode layer  506  may form a complete oral care device  500 . In operation, the oral care device  500  may be placed in a user&#39;s oral cavity and current is passed through the electrodes  508  to provide an electrochemical benefit in the oral cavity. As discussed above, the benefit may constitute release of ions or the like upon degradation of the electrode  508 . To promote the release of ions, the electrodes may be exposed to the environs of the oral cavity, e.g., such that saliva can act as an electrolytic solution. Alternatively, the covering  512  may be disposed over the electrodes, such that the electrodes are sandwiched between the covering and the electrode substrate. In this manner, the electrode substrate  510  and the covering  512  form a housing containing the electrodes. The covering  512  and/or the electrode substrate  510  may be formed to allow migration of saliva or other fluids therethrough, and into contact with the electrodes. For example, pores or openings may be formed through one or both of the electrode substrate and the covering  512 . Moreover, the covering may be affixed to the substrate only about a periphery of the covering, thereby allowing for a volume around the electrodes. The interface between the electrode substrate and the covering may also be a discontinuous attachment, creating openings or voids through which fluid can enter and leave the volume. 
     While the device  500  may be complete with the base substrate  502 , the power source  504 , the electrode layer  506 , and optionally the covering  512 , one or more optional components may also be included. For example, the device  500  may also or additionally include an adhesive layer  514 , to promote retention of the device  500  in a desired position in the oral cavity. The adhesive layer may include any conventional orally-compatible, releasable adhesive. For example, water-soluble polymers, noted above as an example of a base layer substrate, may also be used as an adhesive in the present disclosure. As illustrated in  FIG. 5 , the adhesive layer  514  may have the same general footprint as the other components making up the strip. As a result, the entire strip may include adhesive. In other embodiments, less adhesive may be included. For example, only portions of the footprint of the strip may be adhesive. For instance, adhesive may be provided only at longitudinal ends of the strip, with the strip being applied much like other commercially available bandages. In other implementations, adhesive may be applied about the periphery of the strip and in still other embodiments the adhesive layer may include a plurality of adhesion points or regions. 
     The oral care device  500  may also include a release layer  516 . The release layer  516  may be a removable member disposed over components of the device  500 , for example to prevent contamination of the oral care device  100  prior to insertion into the mouth. The release layer  516  illustrated in  FIG. 5  comprises a thin sheet of flexible material, e.g., a polymeric material, that a user peels off to reveal the electrode layer, covering and/or adhesive layer, depending upon the construction of the device  500 . When the adhesive layer  514  is present, for example, the release layer will ensure that the adhesive remains tacky until the device  500  is to be used. Although the release layer  516  is shown as a single layer, in other embodiments the release layer may instead take the form of an envelope or complete package, e.g., for completely retaining the oral care device  500  therein. 
     In some embodiments, the release layer  516  may also control activation of the device  500 . For example, the release layer may include a physical obstruction that prevents electrical communication between the power source  504  and the electrodes  508 . Removing the release layer will also remove this obstruction, thereby allowing current to flow from the power source to the electrode  508 . In other implementations, removal of the release layer  516  may be detected, e.g., using a presence/absence sensor, and the output from that sensor may trigger powering-up of the device. 
     Although not illustrated, the device  500  may also include control circuitry or similar features to control the electrical circuit created by the power source  504  and the electrode  508 . For example, the control circuitry may alternate the polarity of the electrodes during use. Alternating the polarity may prevent accumulation of charged particles or ions on the electrodes. The control circuitry may also be programmed to control an amount of current supplied to the electrode  508 . The control circuitry may also include a power-up function, or the like, to activate the power source when the device is ready for use. The control circuitry may include a manual switch as part of the power-up function, such as a toggle or push button switch. Moreover, as discussed above, the release layer could also be integrated into the power-up function, e.g., such that removal of the release layer powers up the device. In other embodiments, the control circuitry may include sensor outputs. For example, a conventional presence/absence sensor could be disposed to be covered by the release layer, and detect removal of the release layer. This detection could then be used to turn on the device. In another embodiment, a water- or liquid moisture-detecting sensor may be provided. When the sensor comes in contact with saliva, i.e., upon being inserted into the mouth, the power source is turned on. The control circuitry could be provided on a separate layer, or could be integrated into another layer. For example, it may be desirable to incorporate the control circuitry into the electrode layer, the base layer, and/or the power source layer. 
     As will be appreciated, the oral care device  500  is generally a thin, flexible device capable of simple insertion into the oral cavity. Depending upon the benefit to be achieved from the device, the device may be placed over one or more teeth, on the gums, on the inside of the cheek, and/or on or under the tongue. In some embodiments, it may be desirable to situate the electrodes as close to the teeth as possible. Because the device is flexible, in some examples the device can be folded, for example, proximate the longitudinal axis  518 , such that device can be placed around one or more teeth with one of the electrodes  508  in front of the tooth/teeth and the other of the electrodes  508  disposed behind the tooth/teeth. In this manner, the electrical field generated at the electrodes  508  would pass through the tooth/teeth disposed between the spaced electrodes  508 . This arrangement disposes the electrodes in intimate contact with the teeth. Such an arrangement may also be beneficial to drive ions released from the sacrificial electrode(s) into the tooth enamel. 
     In another, similar implementation, the oral care device may take the form of a molded tray. For example, the base substrate  502  may be relatively rigid, such as molded. In still further alternatives, the power source may be disposed outside the oral cavity and/or separate from the device  500 , yet electrically connected to the electrodes. Other modifications will also be appreciated by those having ordinary skill in the art, with the benefit of this disclosure. 
     Yet other implementations of this disclosure are illustrated in  FIGS. 6-8 .  FIG. 6  shows a container  600  for a dentifrice, which may be a liquid dentifrice, such as mouthwash or whitening solution, for example. The container  600  includes a body  602  and a cap  604  configured for selective placement on and removal from the body  602 . 
       FIGS. 7 and 8  illustrate examples of the cap  604 , as shown in  FIG. 6 . In  FIG. 7 , a cap  700  includes an annular sidewall  702  terminating at a closed end  704 . The sidewall  702  and the closed end  704  define a volume. Threads (not shown) or another known mechanism may be provided on an inner surface of the sidewall  702  to promote attachment of the cap  702  to a container body. A first electrode  706  and a second electrode  708  also are disposed on the inner surface of the sidewall  702 . The electrodes  706 ,  708  are illustrated as spaced-apart metallic windings fixed to the sidewall  702 . Although not illustrated, a power source electrically connects the electrode  706 ,  708  to provide a potential difference between the electrodes. When the power source is activated, an electrical field is created between the electrodes. As in embodiments discussed above, one of the electrodes preferably is a sacrificial electrode, made of a sacrificial metal such as zinc. 
     The closed end  704  of the cap  700  is relatively flat, such that the cap  700  may be placed on a flat surface, with the closed end  704  resting on the surface. In this manner, the volume defined by the sidewall  702  and the closed-end  704 , can hold a substance, such as the dentifrice carried in the container. In use, the cap  700  is filled with the dentifrice and power is applied across the electrodes  706 ,  708 . The dentifrice acts as an electrolyte, and ions from the sacrificial metal comprising the sacrificial electrode are released into the dentifrice. A user then empties the contents of the cap  700  into his mouth so the ions may provide an oral benefit. This oral health benefit may be in addition to any benefit received from the dentifrice itself. In other uses, the cap  700  may be used separately from the dentifrice contained in the container. For example, the cap  700  with electrodes  706 ,  708  may be filled with water and ions from the electrodes may be released into the water. The user may then rinse with the ion-infused water to obtain an oral health benefit separate from the dentifrice. 
     Although the power source and electrical connections between the power source and the electrodes  706 ,  708  are not illustrated in  FIG. 7 , those components may be disposed proximate the closed end  704  of the cap  700 . A false end or other substrate may be provided over the power source and/or electrical connections to ensure that fluid in the cap  700  does not contact those components. Similarly, it may be desirable to substantially shield the electrodes from the atmosphere. In one implementation, the sidewall  702  may comprise two concentric sidewalls with the electrodes disposed between the concentric walls. Thus, the user may grasp the outer sidewall when removing the cap from or placing the cap on the container while the inner sidewall is visible inside the cap. In this embodiment, the inner sidewall may be provided with apertures or other holes that allow for fluid flow into the space between the concentric sidewalls, such that the fluid contained in the cap may come into contact with the electrodes. 
       FIG. 8  is another example implementation of a cap  800 , such as the cap  604  of  FIG. 6 . In this example, the cap  800  includes an annular sidewall  802  terminating at a closed-end  804 , much like the embodiment illustrated in  FIG. 7 . Two electrodes  806 ,  808  are disposed to depend from the closed end  804  into a volume defined by the sidewall  802  and the closed-end  804 . The electrodes  806 ,  808  are illustrated as parallel plates, although they may take other forms, including but not limited to the wound electrode configurations illustrated in preceding embodiments. As with previous embodiments, at least one of the electrodes is preferably a sacrificial electrode, formed of a sacrificial metal. Use of the cap  800  is similar to that of the cap  700  described above and will not be described again here. 
     Although not illustrated, the caps  700 ,  800  may also include a user interface, such as a button or switch that is pressed by a user to activate the electrodes. Control circuitry, which may include timing circuitry, may be provided to activate the electrodes for a predetermined amount of time, for example in response to user interaction with the user interface. The timing may be sufficient to release a predetermined amount of ions from the sacrificial electrode, for example. An indicator or the like, such as an indicator light or sound may also be provided to indicate to a user that the activation of the electrodes is complete. 
     Other modifications to the container and cap embodiment also are contemplated. For example, containers are known that have a separate reservoir proximate an open mouth of the container. In these containers, a user squeezes a main body of the container to move fluid to the reservoir. The reservoir may include gradations or other markings as visual indications of an amount of the fluid in the reservoir, for example. According to an embodiment of this disclosure, a pair of electrodes may be provided in the reservoir. Also, the power source and the electrical connections may be associated with the container body, instead of the cap. 
     The foregoing embodiments illustrate example devices related to oral health that incorporate electrodes. At least one of the electrodes is a sacrificial electrode, made of a sacrificial metal. For example, the sacrificial electrode may be made of zinc, which may be 90% or more pure zinc. When an electrical potential is produced across the electrodes, zinc ions are released into an electrolyte, which may be saliva, water, or a dentifrice. In embodiments of this disclosure, the electrolyte is then transferred to the oral cavity to provide a benefit to the oral cavity. For example, when zinc is used as the sacrificial metal, the electrolytic fluid will carry zinc ions, which act as an antibacterial agent in the oral cavity. Other sacrificial metals, such as iron, or tin, may also or alternatively be used, to provide other or additional oral benefits. When the electrolyte used is a dentifrice solution, such as a mouthwash or tooth whitening agent, the electrodes may also act to activate components in the dentifrice. 
     Although other or additional metals may be used in the sacrificial electrodes, the inventors have conducted a number of tests using zinc. 
     In one example test, a manual toothbrush (Colgate  360  toothbrush) was used to simulate brushing. Specifically, simulated brushing was performed in a 10 mL vial with 1 gram of great regular flavor toothpaste and 1 mL saliva. Also in the test, a toothbrush as illustrated in  FIG. 4  was provided. Each of the electrodes of the toothbrush comprised zinc wire wound in a figure-eight about spaced posts. Simulated brushing also was performed using this toothbrush in a 10 mL vial with 1 gram of great regular flavor toothpaste and 1 mL saliva. The brushing using the toothbrush with electrodes was done with the brush in an OFF state as well as in an ON state. In the ON state, current was provided at approximately 2 mA and voltage was set to 2V. 
       FIG. 9  shows the results of the just-described example test. Specifically,  FIG. 9  illustrates a concentration of zinc in saliva (as parts per million) for two iterations of simulated brushing for each state, i.e., manual toothbrush, electrode toothbrush in OFF state, and electrode toothbrush in ON state. In this example, the samples were tested using inductively coupled plasma atomic absorption spectroscopy. 
     In additional tests, an ATP or bioluminescent assay and a Resazurin assay were completed for a strip (like that shown in  FIG. 5 ), a tray and a toothbrush (“eTB”—as shown in  FIG. 4 ).  FIG. 10  shows the results of the ATP assay and  FIG. 11  shows the results of the Resazurin assay. The Planktonic resazurin assay was used to determine the relative amount of bioactive metal compound in a formula. This assay uses a mixed species bacterial inoculum and the metabolic indicator dye resazurin is used as a measure of bacterial viability following treatment. The ATP or bioluminescent assay is used to measure total generic bacteria. For both assays the five species mix of planktonic bacteria ( Actinomyces viscosus, Lactobacillus casei, Streptococcus oralis, Veilonella parvula  and  Fusobacterium nucleatum ) is treated for one hour with the indicated dilution of dentifrice. Following treatment, the samples are washed and incubated with the non-fluorescent blue dye resazurin. When metabolically active cells reduce resazurin, it is converted to the pink fluorescent dye resorufin. The ATP assay uses the luciferin-luciferase ATP-dependent reaction to evaluate the viability of populations of organisms. By comparing the fluorescence of the test cultures to a standard curve, we can determine the percentage of the initial population of bacteria that remains viable after the one hour treatment. 
     The ATP viability data illustrated in  FIG. 10  is also shown in Table 1: 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 ATP viability 
               
            
           
           
               
               
               
            
               
                   
                 Product 
                 % Viability 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                   
                 ZnCl gen tray 
                 56.19 
               
               
                   
                 ZnCl gen eTB 
                 57.93 
               
               
                   
                 ZnCit gen tray 
                 19.44 
               
               
                   
                 ZnCit gen eTB 
                 20.57 
               
               
                   
                 NaCl eTB-a 
                 23.51 
               
               
                   
                 NaCl eTB-b 
                 21.92 
               
               
                   
                 Citrate eTB-a 
                 46.62 
               
               
                   
                 Citrate eTB-b 
                 60.71 
               
               
                   
                 1% ZnCl soln 
                 20.82 
               
               
                   
                 1% ZnCl soln 
                 31.73 
               
               
                   
                   
               
            
           
         
       
     
     The Resazurin viability data illustrated in  FIG. 11  is also shown in Table 2: 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Resazurin viability 
               
            
           
           
               
               
               
            
               
                   
                 Product 
                 % Viability 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                   
                 ZnCl gen tray 
                 37.71618426 
               
               
                   
                 ZnCl gen eTB 
                 34.24028388 
               
               
                   
                 ZnCit gen tray 
                 13.2054818 
               
               
                   
                 ZnCit gen eTB 
                 16.81131976 
               
               
                   
                 NaCl eTB-a 
                 20.64760777 
               
               
                   
                 NaCl eTB-b 
                 17.23116481 
               
               
                   
                 Citrate eTB-a 
                 37.74257346 
               
               
                   
                 Citrate eTB-b 
                 33.95196444 
               
               
                   
                 1% ZnCl soln 
                 15.7617772 
               
               
                   
                 1% ZnCl soln 
                 26.64967783 
               
               
                   
                   
               
            
           
         
       
     
     The test results illustrated in  FIGS. 10 and 11  and Tables 1 and 2 show that a tray, a strip and an electric toothbrush may be used to deliver zinc electrochemically. The zinc may enhance already existing products, including those whose original purpose may have been other than therapeutic. 
     The foregoing examples describe oral care implements incorporating a sacrificial electrode to release ions that provide benefits in the oral cavity. To the extent that some implementations contemplate placing electrical components and/or generating electrical fields in the oral cavity, it should be noted that the devices are operated with sufficiently low current and voltage that will not have an adverse effect to the oral cavity or the user. For example, currents are on the order of not more than 5 milliamps and voltages of no greater than about 3 Volts may be used to generate ions according to embodiments of this disclosure. 
     Although example embodiments have been described in language specific to the structural features and/or methodological acts, the claims are not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the example embodiments.