Patent Publication Number: US-2012040308-A1

Title: Hand-held teeth treatment device

Description:
The present invention relates to a hand-held teeth treatment device, an applicator and set of applicators for the device and to a device for applying a plurality of different types of treatment to teeth, such by application of an active gaseous species. The present invention also relates to a teeth treatment kit. 
     An active gaseous species, for example, one contained in a non-thermal gaseous plasma, can be used in a number of different oral treatments. The active species may, for example, be used to combat dental caries or whiten teeth. 
     US-A-2004/0255409 relates to an electric toothbrush of a conventional kind, that is a device having a brush head which is contacted by the user with his or her own teeth in order to clean them. The electric toothbrush has a removable brush section having a transponder communicating with a handle portion of the toothbrush via a non-contacting inductive coupling. The data transmitted between the brush section and the handle section may include data for activating the motor or other driving means of the toothbrush. 
     The present invention provides a hand-held teeth treatment device or kit for applying a plurality of different types of treatment to teeth, comprising: 
     a base unit which is configured to be hand-held and -operated, and comprises a source of electrical energy; 
     a plurality of interchangeable applicators comprising applicator heads for applying different respective treatments to teeth, each of said applicators having a connecting portion for engaging with a complementary connecting portion of the base unit for connecting the applicator to the base unit such that any one of said applicators can be connected to said base unit; 
     treatment generating means for receiving electrical energy from said source, the treatment generating means being configured for generating an active gaseous species for application by at least a chosen one of the applicators when the chosen applicator is connected to said base unit; and 
     treatment activation means for allowing generation of a type of treatment according to the respective applicator connected to the base unit, wherein the connecting portion of each of said applicators comprises means co-operable with the connecting portion of the base unit for selecting the type of treatment which can be generated by the device when the applicator is connected to the base unit. 
     Accordingly, the treatment generating means can be activated only if an applicator is connected to the base unit. 
     The treatment generating means may be capable of generating any one of a plurality of different types of treatment and said treatment activation means allows generation of any one type of treatment only when a selected said applicator associated with said one type of treatment is connected to the base unit. 
     Accordingly, a user may be able to select from more than one type of treatment. The device is operable to deliver a selected type of treatment according to the type of applicator which is connected to the base unit. 
     One of the applicator and the base unit may comprise locking protrusions and the other of the applicator and the base unit may comprise locking recesses for receiving the locking protrusions for locking the applicator to the base unit. In a set of applicators for use in the device, each applicator may have a different configuration of locking recesses or locking protrusions. 
     The treatment generating means may additionally comprise a motor for moving said applicator head for treating teeth, for example, by reciprocating or rotating movement. 
     Each applicator head may be configured for applying one particular type of treatment to teeth and the connecting portion of said applicator is co-operable with said treatment activation means when the applicator is connected to the base unit for allowing generation of only that particular type of treatment by said treatment generating means. 
     At least one applicator may comprise a duct for connecting with a supply of active gaseous species generated in the base unit when the applicator is connected to the base unit for conveying species from the base unit to the applicator head; wherein the applicator head comprises at least one aperture therein in gas communication with the duct for applying species to an oral treatment region. 
     At least one applicator head may comprise an envelope which is sized and shaped to cover an inwardly and/or outwardly facing surface of one or more teeth and said at least one aperture is formed in the envelope for applying species to said teeth surface. The envelope may be shaped in the form of an arch and sized to cover the inwardly and/or outwardly facing surfaces of the upper and/or lower teeth and a respective plurality of said apertures are formed in said envelope for applying species to said inwardly and/or said outwardly facing teeth surfaces. The or each of the apertures may be configured to be in a closed condition to prevent the application of species to teeth and when clamped between upper and lower teeth, the apertures are opened to allow said application. 
     At least one applicator may comprise a motor for receiving electrical energy from said source when the applicator is connected to the base unit, said motor when activated causing movement of said applicator head. The applicator head may comprise a brush and said motor is adapted for causing one of reciprocating, rotational or vibrational movement of said brush. 
     The invention also provides a teeth treatment kit comprising a device as described above, there being a plurality of applicators, each applicator enabling a different treatment to be performed, whereby a user can select from the plurality of applicators a particular one to perform a particular treatment. 
     The device may be self-contained wherein during application of treatment said treatment generation means generates treatment without the device being connected to a remote source of gas and/or power. 
    
    
     
       In order that the present invention may be well understood, embodiments thereof, which are given by way of example only, will now be described with reference to the accompanying drawings, in which: 
         FIG. 1  shows a hand-held teeth treatment device; 
         FIG. 2  shows the device in  FIG. 1  modified for applying a plurality of different types of treatment to teeth; 
         FIG. 3  shows schematically apparatus comprising a device for generating a non-thermal plasma for application to teeth and a recharging unit for recharging the device; 
         FIG. 3   a  shows a modified apparatus; 
         FIG. 4  show cut-away views of the device in  FIG. 3 ; 
         FIG. 5  shows a first applicator of the device in  FIG. 3 ; 
         FIG. 6  shows a second applicator of the device in  FIG. 3 ; 
         FIG. 7  shows a third applicator of the device in  FIG. 3 ; 
         FIG. 8  shows schematically connection of the applicator shown in  FIG. 5  to the housing; 
         FIG. 9  shows schematically connection of the applicator shown in  FIG. 6  to the housing; 
         FIG. 10  shows a fourth applicator of the device; 
         FIG. 11  shows a fifth applicator of the device; 
         FIG. 12  shows a sixth applicator of the device; 
         FIG. 13  shows seventh and eighth applicators of the device; 
         FIG. 14  shows ninth and tenth applicators of the device; 
         FIG. 15  shows eleventh and twelfth applicators of the device; 
         FIG. 16  shows a thirteenth applicator of the device; and 
         FIG. 17  shows a fourteenth applicator of the device. 
     
    
    
     Referring to  FIG. 1 , a hand-held teeth treatment device  1  is shown. The device  1  comprises a base, or hand, unit  2  which is configured to be hand-held and operated and an applicator  3  comprising an applicator head  4  for applying treatment to teeth. The applicator comprises a connecting portion  5  for engaging with a complementary connecting portion  6  of the base unit for connecting the applicator to the base unit. Treatment generating means  7  receives electrical energy from a source of electrical energy  8  for generating treatment for application by the applicator. Treatment activation means  5 ,  6  (described in more detail below with reference to  FIGS. 8 and 9 ) allow activation of the treatment generating means only when the applicator  3  is connected to the base unit  2 . 
     As shown in  FIG. 2 , the device  1  is capable of applying a plurality of different types of treatment to teeth. A plurality of applicators  3   a ,  3   b  and  3   c  comprise applicator heads  4   a ,  4   b ,  4   c  for applying different respective treatments to teeth. Each applicator has a connecting portion  5   a ,  5   b ,  5   c  for engaging with the complementary connecting portion  6  of the base unit for connecting the applicator to the base unit  2  such that any one of the applicators can be connected to the base unit. 
     The treatment activation means allows activation of the type of treatment generated according to the applicator which is connected to the base unit. For example, applicator  3   a  has an applicator head  4   a  in the form of a brush to which a reciprocating motion can be imparted by a motor for cleaning teeth. The motor may be housed in the base unit  2  but in a preferred arrangement the motor is housed in the applicator and connected to the source  8  of electrical energy via treatment activation means  5 ,  6 . In another example, applicator  3   b  has an applicator head  4   a  in the form of a brush to which a rotating motion can be imparted by a motor for cleaning teeth. In the third example, the treatment generation means  7  is configured for generating an active gaseous species and the applicator  3   c  is adapted to convey species to the applicator head  4   c  for application to teeth. Depending on the type of species selected, the teeth may be treated for example by cleaning or whitening. The active gaseous species may be a non-thermal plasma further details of which are provided below. 
     Accordingly,  FIG. 2  shows a teeth treatment kit comprising a device  1 , there being a plurality of applicators  3   a ,  3   b ,  3   c , each applicator enabling a different treatment to be performed, whereby a user can select from the plurality of applicators a particular one to perform a particular treatment. Depending on the type of applicator connected to the base unit, any one of a plurality of different treatments can be performed. For example, as shown in  FIG. 2 , the device can treat teeth by reciprocating or rotational motion of a brush or by application of a gaseous species to teeth. Alternatively, the device can be adapted for treatment of reciprocating and rotational motion of a brush but without the capability of application of a gaseous species. Still further and as described in more detail below, the device may be capable of applying active gaseous species, optionally with more than one applicator, but without the capability of treatment by abrasive action with a brush. An applicator may also be provided which de-activates electric action of the device so that traditional manual brushing may be performed. 
     Referring to  FIGS. 3 and 4 , a device  10  is shown for generating a non-thermal plasma  24  which may be a flow of plasma in the form of a plasma plume emitted from the device. The device is disclosed in detail in the applicant&#39;s co-pending international application entitled “Device For Generating Gaseous Species”, which was filed on the same date as the present application. The contents of the co-pending application are hereby incorporated by reference. 
     The treatment generating means comprises a gas capsule  12  for holding a gas  14  under pressure and forming a flow of gas through a expansion chamber  16  to an plasma generator ( ) then to an applicator  18  when released from the gas capsule and plasma generation means  22  electrically connected to a source of electrical energy for energising gas  14  in the plasma generator  16  to form a gas plasma  24 . 
     In a modified device shown in  FIG. 3   a , high pressure gas may flow from the capsule through an orifice plate  13  into an expansion chamber  15  which slows flow and which can then be released in a controlled way to the reaction generator  16 . 
     A housing  28  of the base unit houses the gas capsule  12 , expansion chamber plasma chamber  16 , source of electrical energy  20 , and plasma energising means  22 . The device is sized and of a weight such it can be held and operated by a user by hand and the gas plasma  24  readily applied by a user to treat a treatment region of an object or human or animal body. In this regard, the device is operable without the requirement for its connection by a gas line to a gas supply. The device  10  may also receive power from the source without the requirement for electrical cabling connecting the device to a mains supply. In this regard, the device is self-contained wherein during application of treatment said treatment generation means generates treatment without the device being connected to a remote source of gas and/or power. However, in other embodiments of the invention the device may be connected to receive gas or power from a supply. 
     The device  10  has particular utility in, for example, teeth whitening, dry cleaning of teeth, or treatment of gingivitis and periodontis. The application for teeth whitening is described in more detail in the applicant&#39;s co-pending application number GB 0823435.3 filed 23 Dec. 2008, the contents of which are hereby incorporated by reference. In this regard, the treatment region may be a single tooth, two teeth or the upper and/or lower arch of teeth. Alternatively, the treatment region may be a portion of the gingiva or a pocket. Still further, the treatment region may be the oral cavity. The flow rate of non thermal gaseous plasma may be selected according to the treatment. 
     The components of device  10  will now be described in more detail, giving modifications and alternatives where relevant. 
     A control indicated generally at  30  is provided for selectively releasing gas from the gas capsule for forming the flow of gas. As shown in this example, the control  30  comprises a valve  32  which when open allows the flow of gas through a conduit from the gas capsule optionally through an expansion chamber to the plasma generator, and when closed resists flow. The control  30  comprises a mechanical push switch  34  which can be operated by a user for controlling the valve  32 . 
     The housing  28  comprises means  36  for locating the gas capsule  12  in the housing so that the gas capsule is operable to release gas for forming the gas flow. The housing may further comprise a gas release mechanism operable for releasing gas from the gas capsule when the locating means locates the gas capsule in the chamber. 
     As shown in  FIG. 3  and described in more detail below, the device  10  comprises a filler valve  52  for allowing gas from a gas supply to re-fill or recharge the gas capsule  12 . 
     The plasma energising means  22  comprises two electrodes  54 ,  56  for generating an electric field in the plasma chamber  16 . A signal generator  58  generates an electrical signal for driving, or energising, the electrodes. At least one, and preferably both or all, of the electrodes are dielectric barrier discharge electrodes insulated from gas in the plasma generator by a dielectric to prevent heating of the plasma in response to the transfer of electrical charge between plasma in the plasma chamber and the electrodes. Suitable dielectric materials are ceramic, plastics or glass. 
     The plasma energising means may  22  may operate in any of one or more plasma energising modes for example alternating, DC, pulsed, and can be capacitively coupled or inductively coupled to the plasma generator In this example, the signal generator  58  is configured to generate a pulsed DC signal for driving the electrodes. The signal generator may be configured as a pulsed signal generator to generate a low duty cycle signal in which the electrical energy is provided to the electrodes for less than 10% of the duty cycle. 
     The control  30  is operably connected to the plasma energising means  22  for controlling energisation of, or supplying energy to, the electrodes. In this example the control  68  comprises an electrical switch  70  which when closed allows energisation of the electrodes  54 ,  56 . The switch  70  is manually operable by a user using the previously referenced button switch  34  (which also activates valve  32 ). The use of the same user input device for controlling the flow of gas into the plasma chamber and the energisation of the electrodes  54 ,  56  is desirable because preferably gas flow and energisation of the electrodes occurs at the same time. Further, it is preferable that energisation of the electrodes does not occur unless gas flow exceeds a predetermined minimum required flow. 
     The source  20  of electrical energy may be one or more batteries and preferably the batteries are rechargeable. In this case, the housing  28  may comprise an electrical socket for receiving a plug connected to a mains power source and a recharging circuit  82  for recharging the batteries. 
     The housing  28  comprises an enclosure  84  for locating the batteries in the housing and electrical terminals (not shown) which connect to the batteries when they are located in the enclosure for supplying energy to the plasma energising means  22 . 
     In order to permit a free range of movement of the device by a user, it is preferable that the source of electrical energy is not connected to a mains or other supply during use. It will also be appreciated that as the device may be used in a wet environment for instance a bathroom it is advantageous to avoid cabling. 
     Various embodiments of the applicator are shown in more detail in  FIGS. 5 to 17 . 
     Referring to  FIG. 5 , an applicator  90  is shown which is connectable to a housing of the device  10  for applying active gaseous species generated inside the housing  28  to an oral treatment region. The applicator  90  comprises a connecting portion  94  comprising connecting formations  95  for engaging with complementary connecting formations  96  of the housing for connecting the applicator to the housing. A duct  88  connects with the supply of active gaseous species generated in the housing when the connecting portion is connected to the housing and conveys the species from the housing to an applicator head  92 . The applicator head is configured for treatment of an oral treatment region and has one aperture  99  therein in gas communication with the duct for applying species to the oral treatment region. The applicator head  92  is sized and shaped for introduction to an oral cavity for treatment of one or more teeth. In this example, the head comprises a flexible skirt  101  which can fit over two teeth so that species ejected through the aperture  99  are applied to the surfaces of the teeth. The head  92  is adapted such that when it is fitted in position substantially all of the surface area of the enamel of the teeth, and optionally a proximate portion of gingival, is exposed to plasma or other active gas species for treatment. 
     Two further ducts  116  are in flow communication with the applicator head for evacuating species from the treatment region to the housing after treatment. Ducts  116  form an exhaust duct in the applicator  90  extending from the treatment region and in fluid communication with pumping means  118  in the device  10 . The pumping means  118  is driven by a motor  120  for pumping gas or plasma from the treatment region. It is preferable that gas or plasma is exhausted from the treatment region after treatment so that a user does not inhale significant quantities of gas or plasma. 
     In this example, the formations of the connecting portion are shaped protrusions  95  which are received in a respective plurality of shaped recesses  97  in the housing connecting portion  96 . Once received in the recesses, the applicator and housing are relatively rotated to lock the applicator in place. 
     The connecting portions  94 ,  96  are configured to allow activation of one or more functions of the device  10  when connected and to prevent activation of functions when not connected. Similarly, as a user may choose from any one of a plurality of different applicators (described below in more detail) the connection of one applicator to the housing may allow activation of one set of functions whilst the connection of another applicator to the housing may activate another set of functions. In this regard, each applicator of a set of applicators may have a different configuration of locking recesses or locking protrusions. The connection of applicator  90  to housing  28  is configured to allow activation of the plasma energising means  22  and of gas flow to plasma chamber  16  when user input device  34  is operated. Without such connection, operation of the user input device cannot activate these functions. 
     As shown in  FIG. 5 , the connecting portions  94 ,  96  comprises treatment activation means which in this example comprise complementary electrical contacts which are closed to allow activation of certain, selected, functions. The arrangement is shown schematically in  FIG. 8 . In  FIG. 8 , connecting portion  94  is rotatable in connecting portion  96  to lock the applicator to the housing. When locked, electrical contacts  98  on the connecting portion  94  contact electrical contacts  100  on the connecting portion  96  thereby closing respective electronic switches allowing activation of the gas flow by valve  32 , activation of the plasma energising means by switch  70 , and activation of evacuation means  102 . 
     Accordingly, if a correct applicator is not connected to the housing, gas flow and energisation is not permitted thus conserving gas and power if the push button  34  is inadvertently operated. 
     When a different applicator is connected to the housing different functions of the device are allowed. In this regard,  FIG. 9  shows schematically an applicator  110  illustrated in more detail in  FIG. 6 . Applicator  110  comprises an applicator head  112  similar to a typical tooth brush comprising bristles  111  for cleaning teeth. Applicator  110  further comprises connecting portion  114  for engaging with connecting portion  96  of the housing  28 . Ducting is not required in applicator  110  between the connecting portion  114  and the head  112  as the applicator  110  is designed to be used without plasma treatment. As shown in  FIG. 9 , when connection portion  114  is received in connecting portion  96  and rotated to lock applicator  110  to the housing  28 , electrical contact  106  on connecting portion  114  contacts electrical contact  108  on the connecting portion  96  thereby closing an electronic switch allowing activation of for example a motor  104  for imparting rotating or reciprocating motion to the brush of the applicator head for aiding teeth brushing. The other functions of device  10  ( 32 ,  70 ,  102 ) are deactivated in this arrangement so that plasma is not delivered when normal teeth brushing is performed. 
     Although applicator  110  is shown comprising an electrical contact for activating a motor, instead connecting portion  114  may be devoid of electrical contacts and the applicator  110  is then used as a normal tooth brush with all other available treatments deactivated. 
     A third applicator  122  is shown in  FIG. 7  which is generally similar to applicator  90  shown in  FIG. 8  although with a different head and without the evacuation ducts  116 . The species release portion of applicator head  124  comprises a plurality of fine hollow tubes, or fibres,  125  in the form of a brush for directing plasma or active gas species onto a treatment region such as the teeth of a user. One end of each fibre is in flow communication with the duct and the other end of each fibre forms an aperture for applying species to a tooth surface. The fine hollow tubes may be formed by any suitable technique. The tubes may be connected to a plenum chamber, or manifold cavity,  127  in the head for distributing generally equally plasma or active species to the tubes. 
     A fourth applicator  160  is shown in  FIG. 10 . Applicator  160  comprises similar features to those discussed above in relation to  FIG. 3  and those similar features will not be described again in detail for brevity. 
     Applicator  160  is shown connected to housing  28  of device  10 . An applicator head  162  is flexible curved and hollow, and sized to fit over one or more teeth  166  as shown. The head is connected to a neck portion of the applicator by a ball joint  168  to allow pivotal movement of the head relative to the rest of the device  10 . A plurality of apertures  170  are formed in an inner surface of the head so that when the head is in position in an oral cavity the apertures face the teeth. The length and curvature of the head is chosen so that it can fit over each of the teeth in a typical mouth (e.g. molars and incisors) and locate the apertures  170  closely adjacent to the surface of the tooth to be treated. If the apertures are located too far from a tooth surface the species may become diluted by mixing with ambient air and therefore be less effective in treating the teeth. If the apertures are located too close to a tooth surface, the tooth surface may itself block the aperture or the species may be concentrated at only one portion of the tooth surface. 
     In this example, the upper and lower teeth can be treated in zones, one zone after another until the mouth is fully treated. Each zone  165  may comprise one or more teeth. The hollow interior of the head forms a plenum chamber in flow communication with both duct  88  for receiving species generated inside the housing  28  and the apertures  170  to allow a relatively equal amount of species to flow from each of the apertures. The apertures are positioned so that an inwardly facing surface  167  and an outwardly facing surface  169  of teeth in a zone are treated together. 
     A fifth applicator  172  is shown in  FIG. 11 . Applicator  172  comprises similar features to those discussed above in relation to  FIG. 5  and those similar features will not be described again in detail for brevity. 
     Applicator  172  comprises an applicator head  174  which is generally arch shaped and sized to cover the inwardly and outwardly facing surfaces of the upper or lower teeth. A plurality of apertures  176  are formed in the inner surface of the head for applying species to the teeth. In more detail, the head  174  forms a channel for receiving a full row of either the upper or the lower teeth. The apertures are located closely adjacent to the teeth surfaces when the head is fitted so that species can flow over the exposed teeth surfaces thereby treating all the upper or lower teeth together. 
     The connecting portion  178  of the applicator extends through 90° for convenient holding of the housing and is swivel fitted to the head  174  so that a user can use the device  10  with the housing extending downwardly from the mouth as shown for treating both the upper and the lower teeth. 
     The arrangement shown in  FIG. 11  is advantageous in that all of the upper or lower teeth can be treated together making efficient use of gas and reducing the time of treatment. 
     A sixth applicator  180  is shown in  FIG. 12 . Applicator  180  comprises similar features to those already discussed above and those similar features will not be described again in detail for brevity. 
     Applicator  180  comprises a head  182  which is configured for treating the inwardly and outwardly facing teeth surfaces of both the upper and lower teeth together. The head  182  comprises a first, front, curved piece  184  adapted to be received between the teeth and the lips and a second, rear, flexible curved piece  186  adapted to be received behind the teeth. Apertures  188  are formed in the rear surface of the front piece and in the front surface of rear piece. A connecting piece  190  extends through a hole  192  in the front piece  184  and is fixed to the rear piece  186  so that when a user fits the head  182  over their teeth, the housing  28  can be pulled to bring the front and rear pieces towards each other thereby locating the apertures  188  relatively close to the teeth. Both front and rear pieces are hollow and are in flow communication with duct  88  in the connecting piece  190  for connecting the apertures to the species generator in the housing  28 . 
     Two further applicators  194 ,  196  are shown in  FIG. 13 . Applicator  194  is adapted for treating the outwardly facing surfaces of the upper and lower teeth and applicator  196  is adapted for treating the inwardly facing surfaces of the upper and lower teeth. Since, the outwardly and inwardly facing surfaces of the teeth may require different treatments or different exposure times, the arrangement shown in  FIG. 11  may be advantageous. For example, different exposure times may be required as teeth whitening is more critical for the outwardly facing surfaces of teeth. 
     The applicator  194  comprises an applicator head  198  and a connecting portion  200  containing duct  88  for connecting to the supply of species. The applicator head  198  comprises locating means in the form of bite grips  202  which can be clamped between upper and lower teeth for locating the applicator head in the oral cavity. The head is flexible and biased to adopt a straight configuration. When inserted in the mouth by a user the head is curved and the user bites down on the bite grips to locate the head. The bite grips may comprise cross-extending tabs or flanges  204  to aid location. The head  198  comprises spacing means in the form of projections  206  for spacing the apertures  208  from respective teeth surfaces when the applicator head is located in the oral cavity. Spacing the apertures from the teeth in this way allows gas to spread throughout the surfaces of the teeth generally equally rather than being concentrated at one portion of a tooth surface. 
     The applicator  196  comprises an applicator head  210  and a connecting portion  212  containing duct  88  for connecting to the supply of species. As with applicator  194 , the applicator head  210  comprises locating means in the form of bite grips  214  and flanges  216 . When inserted in the mouth by a user the head is curved and the user bites down on the bite grips to locate the head. The head  210  comprises spacing means in the form of projections  218  for spacing the apertures  220  from respective teeth surfaces when the applicator head is located in the oral cavity. 
     The applicator heads  198 ,  210  are hollow and form respective plenum chambers in flow communication with duct  88  and apertures  208 ,  220 . 
     Two still further applicators are shown in  FIG. 14 . Applicator  222  is adapted for treating the upper teeth or the lower teeth and applicator  226  is adapted for treating both upper and lower teeth together. 
     Applicator  222  comprises an applicator head  226  and a connecting portion  228  containing duct  88  for connecting to the supply of species. The applicator head  226  comprises locating means in the form of bite grips  230  which can be clamped between upper and lower teeth for locating the applicator head in the oral cavity. The head  226  comprises spacing means in the form of projections  232  adapted to be positioned on each side of a tooth for spacing the apertures  234  from both the front and back teeth surfaces when the applicator head is located in the oral cavity. Species entering the head through duct  88  can flow through channels  236  for ejection from apertures  235  at the front and back sections of the head for applying species to front and back surfaces of the teeth. The channels  236  are in flow communication and extend across the head from the front section to the back section. 
     Applicator  224  has the same construction as applicator  22  except that applicator  224  is adapted for treating both the upper and lower teeth. 
     Another applicator  238  is shown in  FIG. 15 . Applicator  238  is similar to applicator  224  and is adapted for treating both the upper and lower teeth together. 
     Applicator  238  comprises an applicator head  240  and a connecting portion  242  containing duct  88  for connecting to the supply of species. The head comprises a central section  244  for clamping between upper and lower teeth. Extending generally orthogonally from the central section (upwardly and downwardly as shown) are a plurality of flexible tabs  246 . The tabs are disposed in pairs and each pair is adapted for enveloping a single tooth in a typical mouth. Channels  248  are formed along the central section for conveying species from the duct  88  to the apertures (not shown). Each tab  246  in a pair comprises one or more apertures for applying species to one side of a tooth. The central portion  244  is hollow and filled with a gas or gel and further comprises a ridge  248  extending along upper and lower sides of the central portion. As the head is flexible, when a user bites down on the ridge  248 , the cavity is compressed and the tabs  246  bend towards the teeth as shown thus closing the distance between the apertures and the teeth. In this way, the head can easily be fitted in the mouth and located covering the teeth and when in use the central section  244  is bitten thereby closing relatively tightly around the teeth. The apertures are configured to be in a closed condition to prevent the application of species to a teeth surface when not in use and when the central section is clamped between upper and lower teeth, the apertures are opened to allow species to flow onto the teeth. Accordingly, species is not consumed until the applicator head is in place. Further, if any teeth are missing, the user cannot clamp on the ridge at the relevant point and therefore the tabs do not close on the gap in the teeth. Accordingly, the apertures do not open, thereby conserving gas usage. 
     A further applicator  250  is also shown in  FIG. 15  which is functionally equivalent to applicator  238  but of simplified design. 
     Another applicator  252  is shown in  FIG. 16 , which is similar in construction to applicator  194  shown in  FIG. 11 . However, applicator  252  comprises energising means for energising gas flowing through the applicator head  254  for generating a gas plasma. The applicator head comprises an inner wall  256  in which apertures  258  are formed for applying species to the front surface of the upper and lower teeth. Extending outwardly from the wall  256  are a plurality of spacing means  260  for spacing the teeth from the wall. The wall  256  comprises an electrically conductive material which when energised causes gas flowing through the apertures to form a plasma. The spacing means  260  provide sufficient space for the energising means to act upon the gas to generate a plasma. 
     A further applicator  262  is shown in  FIG. 17 . The applicator head  264  comprises a pair of rollers  266  which are supported for rotational movement by a bracket  268 . The rollers comprise a plurality of ridges  270  with apertures  272  located between the ridges. In this way, the apertures  272  are spaced from the surface of a tooth and therefore do not become blocked by the tooth surface when in use so that species can circulate without impediment. The rollers  266  are adapted to be placed either side of a row of teeth and drawn along the row applying species to the teeth as the rollers rotate. The bracket may be flexible thereby allowing the rollers to fit over the teeth and exert a small compressive force against the teeth. The applicator head  264  in this embodiment is detachable as shown and may be replaced with a different head  274 . 
     The device  10  may comprise a single applicator for example the applicator  90  shown in  FIG. 5  or alternatively the device  10  may comprise a plurality of interchangeable applicators as shown in any of  FIGS. 5 to 17 , each for performing a specific function. For example, it is desirable to enable a user to brush teeth in the normal way using the device  10  with applicator  110 , optionally with vibration, and also to be able to treat the teeth with plasma or other active species with any one or more of the other applicators. 
     A recharging unit  134  is shown in  FIG. 3 . The recharging unit comprises a recharging pressure vessel  136  containing gas for supplying gas to the gas capsule  12  of the device  10 ; and electrical recharging means  138  for recharging the source of electrical energy  20  in the device. The recharging unit also comprises a control circuit  152  for receiving electrical energy from, for instance, a mains supply. 
     In use of the device  10  for example for whitening, cleaning, sterilising or sealing an oral region of a body, a user selects an appropriate applicator  18  for fixing to the housing  28 . Depending on the applicator, selected functions of the device  10  can be activated when the user operates the user input device  34 . For plasma treatment, the operation of the user input device opens valve  32 , closes switch  70  and activates the evacuation means  102 . Provided there is sufficient gas flow (e.g. helium) into the plasma chamber  16 , the plasma energising means  22  energises gas in the plasma chamber to form a plasma. Although substantially all of the plasma chamber is exposed to an electric field, only a portion of the gas that enters the plasma chamber may be energised to form a plasma. Accordingly, a mixture of gas and plasma flows from the chamber and through the applicator  18 . The user positions the applicator head so that the gas plasma mixes with atmospheric air to generate these gaseous species over the treatment region, for instance one or more teeth. During treatment, evacuation means may evacuate the mixture of gas plasma from the treatment region. When treatment is completed, the user operates the user input device  34  to deactivate gas flow, therefore the plasma energising means  22  and the evacuation means  102 . 
     Inevitably, some plasma interacts with ambient air (e.g. oxygen, nitrogen and argon) causing some chemical break-down forming other active gaseous species. For example, the interaction of the plasma with oxygen may form ozone. Ozone is a strong oxidant and can contribute to the beneficial, or therapeutic, effect on the treatment region as is the case with other active gaseous species. 
     In another embodiment, a device is configured to generate ozone or other active gaseous species without the generation of a non-thermal plasma or by using other energising techniques. 
     Such a device generates a flow of a non-thermal gaseous species and has equivalent features to device  10  except where otherwise stated. The device comprises a gas capsule for holding a pressurised gas and forming a flow of gas through to a reaction chamber to an applicator when released from the gas capsule. Gas released from the gas capsule is energised in the reaction chamber, or plasma generator, to form an active gaseous species. 
     The device further comprises a source of electrical energy and energising means electrically connected to the source of electrical energy for energising gas in the reaction chamber to form the gaseous species. 
     An applicator directs the flow of gaseous species from the reaction chamber for generating a flow of gaseous species from the device. A housing houses the gas capsule, reaction chamber, source of electrical energy, and energising means. The housing is sized and of a weight such that the device can be held and operated by a user by hand and the flow of gaseous species directed to treat the user&#39;s teeth. The pressure vessel may contain oxygen and in this case the gaseous species formed is ozone.