Patent Publication Number: US-2006019220-A1

Title: Sonophotodynamic therapy for dental applications

Description:
CLAIM OF BENEFIT OF FILING DATE  
      This application claims the benefit of U.S. Provisional Application Ser. No. 60/590,421 titled: “Dental Photocidal Therapy by Means of Dental Scalers” filed on Jul. 22, 2004 and U.S. Provisional Application Ser. No. 60/622,463 titled: “Improved Dental Scaler for Use in Photocidal Therapy” filed on Oct. 27, 2004. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates to the use of photosensitizers with irradiation by light energy and/or sonic energy to kill the microbes involved in a number of oral diseases including inflammatory periodontal disease, dental pulp disease and caries, and in disinfecting or sterilizing wounds and other lesions in the oral cavity.  
     BACKGROUND OF THE INVENTION  
      Chronic periodontitis, a form of inflammatory periodontal disease, is the major cause of tooth loss in adults. Patients with chronic periodontitis have inflamed pockets in the gum tissue, or gingiva, surrounding the affected tooth. Layers of bacteria build up in biofilm within these gingival pockets, leaving behind calcified accretions called calculus attached to the tooth and root surfaces. As the bacterial infection progresses, inflammatory exudates from the biofilm as well as host tissue responses can cause progressive breakdown of the hard and soft tissue structures supporting the tooth, ultimately resulting in tooth loss. Bacterial infections of the oral cavity are also gaining recognition as a source of infection in the rest of the body (e.g., bacteremias [infections of the blood], infective carditis, pulmonary disease, etc.) Such infections have also been implicated in implant rejection and may complicate the prognosis for diabetes mellitus and other autoimmune disorders.  
      Conventional methods of treating bacterial infections of the oral cavity include removal of the pockets of subgingival plaque, calculus and biofilms by dental scaling and applications of antibiotics. Dental scaling is performed on patients with periodontal diseases several times a year, in some cases every three months or more frequently. An ultrasonic dental scaler generates ultrasound vibrations in a fluid (e.g., water, saline or the like) that remove subgingival plaque, calculus and biofilm from the gum tissues. The ultrasound vibrations cause cavitation exerting high shear forces directly on the fluid, the calculus, and the plaque surrounding or within the gum tissue, resulting in the detachment of such calculus, plaque and associated biofilm from the gum tissues. The principles of dental scalers are well described in the patent literature. See U.S. Pat. Nos. 2,990,616; 3,089,790; 3,703,037; 3,990,452; 4,283,174; 4,804,364; and 6,619,957. These patents are all hereby incorporated by reference.  
      Unfortunately, dental scaling by itself has had limited success in eliminating bacteria in the oral cavity and long term applications of antibiotics could lead to resistance rendering the antibiotics clinically ineffective. Moreover, applications of antibiotics may not be desirable for immunocompromised patients and patients with denture stomatitis.  
      In addition to treatment of inflammatory periodontal diseases, elimination of microbes in the oral cavity is also preferable in drilled out carious cavities prior to conventional filling and during other forms of dental surgery including endodotic operations involving the interior of the tooth itself.  
      Photodynamic therapy for killing microbes in the oral cavity was disclosed by Wilson, et al. in U.S. Pat. No. 5,611,793 and European Patent No. EP 0637976B2. These patents are herein incorporated by reference. As discussed in these patents, laser light in a certain wavelength and intensity range is used to illuminate a photosensitive compound that has been applied to the infected tissue(s). The laser activates the compound causing the formation of free radicals and other elements that are toxic to microbes residing in the oral cavity.  
     SUMMARY OF INVENTION  
      Because photodynamic therapy has been shown to be effective in killing infectious microbes in the oral cavity, it would be highly desirable if it were incorporated into routine dental care (e.g., dental scaling or the like). It is an objection of the present invention to provide methods that can conveniently and efficiently disinfect a treatment region of the oral cavity while cleaning and removing calculus, plaque and biofilm from such a region.  
      The present invention provides methods that use a photosensitizing composition in conjunction with irradiation by light and/or sonic energy to kill microbes in the oral cavity, a process hereinafter termed “sonophotodynamic therapy”. As described below, the combined administration of light and sonic energy in the presence of a fluid and a photosensitizing compound has a synergistic effect in the killing of microbes in the oral cavity.  
      The application of sonic energy in a fluid can create acoustic cavitation. Acoustic cavitation involves the nucleation, growth and collapse of gas/vapor filled bubbles in a fluid. Cavitation can effectively kill microbes by physical disruption. For example, the mechanical energy in acoustic cavitation can disrupt and disperse plaque (and the microbes surrounding it) by the violent shear forces produced around the bubbles. Free radicals in a fluid have also been detected as a direct result of acoustic cavitation. These free radicals can kill microbes via cell wall disruption and/or lipid peroxidation. The collapse of the bubbles during acoustic cavitation can be accompanied by a simultaneous emission of light (“sonoluminescence”). The light emitted by sonoluminescence is very broadband and may contain ultraviolet light, which can also be directly detrimental to microbes. Light emitted via sonoluminescence, when applied to a photosensitizing composition in the oral cavity, can release more free radicals, causing further killing of microbes.  
      In an aspect of the invention, a method for killing microbes in an oral cavity is disclosed comprising: applying a photosensitizing composition to a locus; applying a fluid and sonic energy to the locus; and irradiating the locus with a light source at a wavelength absorbed by the photosensitizing composition so as to destroy microbes at the locus.  
      In another aspect of the invention, a method for killing microbes in an oral cavity is disclosed comprising: applying a photosensitizing composition to a locus; applying sufficient sonic energy to the locus in order to provide acoustic cavitation so as to destroy microbes at the locus.  
      In yet another aspect of the invention, a method for promoting wound healing is disclosed comprising: applying a photosensitizing composition to a wound; applying a fluid and sonic energy to the wound; and irradiating the wound with a light source at a wavelength absorbed by the photosensitizing composition so as to destroy microbes at the wound.  
      In another aspect of the invention, a method for promoting wound healing is disclosed comprising: applying a photosensitizing composition to a wound; applying sufficient sonic energy to the locus in order to provide acoustic cavitation so as to destroy microbes at the wound.  
      A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portion of the specifications and the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The features and inventive aspects of the present invention will become more apparent upon reading the following detailed description, claims, and drawings, of which the following is a brief description:  
       FIG. 1  illustrates an exemplary apparatus for performing sonophotodynamic therapy in accordance with an aspect of the present invention;  
       FIG. 2  is a side view of a portion of an exemplary probe suitable for use as part of the apparatus of  FIG. 1 ;  
       FIGS. 2A-2C  illustrate exemplary tips suitable for use with the apparatus of the present invention;  
       FIG. 3  illustrates a portion of an exemplary insert suitable for use as part of a probe of the apparatus of the present invention;  
       FIG. 4  illustrates another portion of the exemplary insert of  FIG. 3 ;  
       FIG. 5  illustrates an exemplary connection of an exemplary probe to the remainder of the apparatus of the present invention;  
       FIG. 6  shows an alternative exemplary probe suitable for use in the apparatus of the present invention;  
       FIG. 6A  illustrates a cross-section of the probe of  FIG. 6  taken along line  6 A- 6 A;  
       FIG. 7  illustrates an exemplary portion of the exemplary probe of  FIG. 6 ;  
       FIG. 7A  is a sectional cut-away view of the exemplary portion of the exemplary probe of  FIG. 7 ;  
       FIG. 8  illustrates another exemplary portion of the exemplary probe of  FIG. 6 ;  
       FIG. 8A  illustrates a cross-section of the exemplary portion of  FIG. 8  taken along line  8 A- 8 A;  
       FIG. 8B  is a sectional cut-away view of the exemplary portion of the exemplary probe of  FIG. 8 ;  
       FIG. 9  illustrates another exemplary alternative probe suitable for use in the apparatus of the present invention;  
       FIG. 9A  is a view of an end of the probe of  FIG. 9 ;  
       FIG. 10  provides a workflow diagram of a method of the present invention to kill microbes in the oral cavity; and  
       FIG. 11  provides a workflow diagram of another method of the present invention to kill microbes in the oral cavity. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      The present invention provides methods of killing microbes in the oral cavity by delivering and activating a photosensitizing composition in the oral cavity in conjunction with sonic energy, usually (but not necessarily) provided by ultrasound or sonic dental scaling.  
      I. Definitions  
      The following terms are intended to have the following general meanings as they are used herein.  
      1. Microbes: any and all disease-related microbes such as virus, fungus, and bacteria including Gram-negative organisms, Gram-positive organisms or the like.  
      2. Light: light at any wavelengths that can be absorbed by a photosensitizing composition. Such wavelengths include wavelengths selected from the continuous electromagnetic spectrum such as ultraviolet (“UV”), visible, the infrared (near, mid and far), etc. The wavelengths are generally preferably between about 160 nm to 1600 nm, more preferably between 400 nm to 800 mm, most preferably between about 500 nm to 850 nm although the wavelengths may vary depending upon the particular photosensitizing compound used and the light intensity. The light may be produced by any suitable art-disclosed light emitting devices such as lasers, light emitting diodes (“LEDs”), arc lamps, incandescent sources, fluorescent sources, gas discharge tubes, thermal sources, light amplifiers or the like.  
      3. Locus: any tissue, carious cavity, endodontic chamber, wound, or lesion in the oral cavity where anti-microbial treatment is desired.  
      4. Wound: any wound or lesion outside of the oral cavity where anti-microbial treatment is desired.  
      5. Photosensitizing composition: a composition comprising at least one suitable art-disclosed photosensitizer. Arianor steel blue, toluidine blue O, crystal violet, methylene blue and its derivatives, azure blue cert, azure B chloride, azure 2, azure A chloride, azure B tetrafluoroborate, thionin, azure A eosinate, azure B eosinate, azure mix sicc., azure II eosinate, haematoporphyrin HCl, haematoporphyrin ester, aluminium disulphonated phthalocyanine are examples of suitable photosensitizers. Porphyrins, pyrroles, tetrapyrrolic compounds, expanded pyrrolic macrocycles, and their respective derivatives are further examples of suitable photosensitizers. Photofrin® manufactured by QLT PhotoTherapeutics Inc., Vancouver, B.C., Canada is yet another example of a suitable photosensitizer. Other exemplary photosensitizers may be found in U.S. Pat. Nos. 5,611,793 and 6,693,093. U.S. Pat. No. 6,693,093 is hereby incorporated by reference. The photosensitizers mentioned above are examples are not intended to limit the scope of the present invention in any way.  
      6. Sonic energy: ultrasound, sonic waves or energy produced by a sonic or ultrasonic device (e.g., dental scaler or the like). It is preferred that the tip vibration of the sonic device is between the range of about 3 KHz to about 5 MHz, more preferably between about 10 KHz to about 1 MHz, even more preferably between about 20 KHz to about 50 KHz, and most preferably between about 25 KHz to about 40 KHz.  
      II. Exemplary Apparatus for Sonophotodynamic Therapy  
      i. Description of the Apparatus  
      Referring to  FIG. 1 , there is illustrated one exemplary apparatus  10  capable of performing sonophotodynamic therapy for killing microbes or bacteria located upon or within tissue. The apparatus  10  includes a probe  12  in communication (e.g., fluid communication, electrical communication or light communication) with the one or more of the following components: a sonic energy source  20 , a light source  22 , a gas source  24 ; a therapeutic fluid (e.g. a photosensitizing composition) source  26  and a cooling and/or lavage fluid source  28  (e.g., water, saline, combinations thereof or other fluids).  
      In the embodiments shown herein, the probes of the present invention are typically illustrated to integrate plural members into a single probe wherein the plural members are configured for guiding light, providing sonic energy, delivering fluid or a combination thereof. It should be understood, however, that these members may be divided amongst multiple probes if desired. It should be further understood that the probe of the present invention may integrate members according to a variety of configurations within the scope of the present invention.  
      The probe  12  of  FIG. 1  is shown in more detail in  FIGS. 2-5 . In the embodiment shown, the probe  12  includes an attachment shown as an insert  34  and the insert  34  includes a member for providing sonic (e.g., ultrasonic) energy, which is shown as a dental scaler tip  42 . The insert  34  also includes a member for providing fluid, which is illustrated as a tube  44  and a member (e.g., a waveguide) for providing light, with is shown as an optical fiber  46 .  
      With reference to  FIG. 2 , the insert  34  is divided into a proximal portion  36  opposite the dental scaler  42  and a body portion  38  located between the proximal portion  36  and the dental scaler  42 .  FIG. 3  then illustrates the proximal portion  36  in greater detail while  FIG. 4  illustrates the body portion  38  and the dental scaler  42  in greater detail.  
      In the illustrated embodiment, the tube  44  extends centrally along substantially the entire insert  34 , the probe  12  or both and substantially defines the body portion  38  of the insert  34 . The tube  44  defines a passageway or tunnel  50  that also extends along substantially the entire insert  34 , the probe  12  or both. Typically, the tube  44  is in fluid communication with therapeutic fluid source  26  via tubes or other members.  
      The optical fiber  46  is located within the tunnel  50  and is substantially coextensive with the tube  44 . As shown in  FIG. 3 , one or more spacers  54  may be employed for positioning or spacing the fiber  46  away from the tube  44 . When used, the spacers  54  typically include openings (e.g., cavities, through-holes or the like) for allowing fluid flow therethrough.  
      The scaler tip  42  is attached to the tube  44  at one end of the tube  44 . The scaler tip  42  defines its own tunnel  56 , which is preferably in fluid communication with the tunnel  50  of the tube  44 . The scaler tip  42  is preferably arced or curved, although not required.  
      Various tips or members may be employed for delivery of sonic energy and the use of the various tips or members contemplates that fluids may be delivered by those tips or members or delivered adjacent the tips or members using a variety of passageways. It is contemplated that a tip or other member may include one hole or multiple holes (e.g., arranged radially) for delivery of light, fluid or both or a tip may be formed of a porous (e.g., a microporous) structure for the delivery of light, fluid or both.  FIGS. 2A-2C  illustrate some examples of alternative tips.  
      As shown in the example of  FIG. 2A , a passageway or tunnel may extend to a distal end of a tip. Alternatively, as shown in the example of  FIG. 2B , a passageway or tunnel may extend only a portion of the distance to a distal end of a tip. As yet another alternative, as shown in the example of  FIG. 2C , a tubular member or multiple tubular members separate from a tip may be configured for fluid delivery.  
      It is contemplated that the skilled artisan may be able to employ a variety of sonic energy sources within the scope of the present invention. Typically, the sonic energy source  20  includes an actuator material that assist in the creation and/or transmission of sonic energy to the member (e.g., the scaler tip) configured for delivery of the sonic energy and an activator for activating the actuator material. As an example, the sonic energy source could comprise a piezoelectric material in electrical communication with an electrical energy source wherein the piezoelectric material converts energy from the electric energy source into ultrasonic vibrations deliverable by a member such as the scaler tip. In particular, the piezoelectric material may deform or vibrate in response to the application of an electrical field at an ultrasonic frequency.  
      Generally, the actuator material may be configured in variety of shapes, sizes or other configurations. For example, the material could extend down the center of the probe and fluid delivery openings or other components of the probe may be outside the actuator material. Alternatively, the actuator material could comprise a plurality of rods and may or may not be tubular in configuration.  
      In the embodiment shown, there is an actuator material  60  integrated into the proximal portion  36  of the insert  34 . The material  60  has a tubular configuration and substantially surrounds a portion of the tube  44  and a portion of the waveguide or fiber  46  of the insert. The particular actuator material  60  illustrated is a magnetostriction material that converts energy from an electric energy source  62  into ultrasonic vibrations deliverable by a member such as the scaler tip.  
      In the particular embodiment shown, the electrical energy source  62  includes excitation drive circuitry  64  configured for communicating the electrical energy from the electrical energy source  62  to the actuator material  60 . In turn, the electrical energy exposes the actuator material  60  to a magnetic field that excites and vibrates the actuator material  60 , which sonically or ultrasonically vibrates the tube  44  the scaler tip  42  or both. It is contemplated that the actuator material may be directly or indirectly connected to the member or tip for initiating the vibration.  
      Preferably, the apparatus  10  includes a controller  70  in signaling communication with the fluid sources  24 ,  26 ,  28  the light source  22  and the sonic energy source  20 . The controller  70  will typically allow a user of the apparatus  10  to control the delivery of fluids, the delivery of light, the delivery and frequency of ultrasonic vibrations of the actuator material  60 , the member or scaler tip  42 , or both by the probe  12 . The apparatus  10  can also include an activation device or switch  72  (e.g., an on/off foot controlled switch) for allowing the user to determine when ultrasonic vibrations, fluid, light or a combination thereof are to be delivered. It will be understood that a variety of different controllers and switches can be developed for controlling the probe and other components of the apparatus  10  within the scope of the present invention and depending upon the degree and type of control desired.  
      In the particular embodiment illustrated, the activation device  72  (e.g., switch or the like) can be linked to the excitation drive circuitry  64  and/or the control circuitry and can be used to control (1) the activation of electrical excitation to the sonic source  20  producing sonic energy; (2) the activation of light from the light source  22 ; and (3) the flow of fluid(s) (e.g., liquid, photosensitizing composition, gas) from the fluid sources  24 ,  26 ,  28  to the probe  12  or a combination thereof. The excitation drive circuitry  64  can also be configured for controlling amplitude of the electrical excitation to the sonic source  20 , the light source, as well as the flow rate of fluid(s) to the probe  12 . Fluid communication tubes  78  are connected and controlled by a switching device  80 . The switching device  80  determines which of the fluid sources  24 ,  26 ,  28  (e.g., the liquid source  28 , the therapeutic source  26  or the gas source  24 ) is delivered to the probe  12  via the tubes  78  and can be controlled by the controller  70 . The switching device  80  can be any art-disclosed switching device and it can be optionally incorporated into the excitation drive circuitry  64 . Thus the switching device  80  can comprise a single switch or solenoid in communication with two or all of the fluid sources, multiple switches or solenoids in connection with respective fluid sources or the like. Moreover, it is possible to have the switching device at least assist in controlling fluid flow rates.  
      In  FIG. 5 , the insert  34  is connected to or placed in communication with the light source  22 , the fluid sources  24 ,  26 ,  28  and the sonic energy source  20  with a connector  86  that is located within a housing  88  of the probe  12 . In the embodiment shown, an end of the proximal portion  36  of the insert  34  is inserted within a seal  90  (e.g. an O-ring) for positioning the insert  34  relative to the connector  86 . The end of the proximal portion  36  is illustrated to include an optional optical element  92  (e.g., a lens, a tapered member, a holographic element, an index matching element or the like) for assisting in coupling light between the source  100  and the fiber  46 . Moreover, the housing includes an electrically conductive material  98  that can expose the actuator material  60  to an electric field, a magnetic field or both.  
      Advantageously, the insert  34  can be removed from the housing and cleaned and sterilized between uses.  
      ii. Operation of the Apparatus  
      In use, the therapeutic fluid source delivers the fluid to the member configured for dispensing the fluid to an area of tissue. Thereafter, the light source communicates electromagnetic radiation to the member configured for delivering light to an area of tissue. Additionally, and typically at a close proximity in time to delivery of the photosensitizing composition or delivery of the light, the sonic energy source provides sonic energy to the member configured for delivering that sonic energy to an area of tissue. It should be understood that the areas of tissue to which the sonic energy, the fluid and the light are delivered are typically one single area of tissue, but such areas may be merely adjacent each other or only partially overlapping as well.  
      With reference to  FIGS. 1-5 , light is communicated from the light source  22  (e.g., a laser source) along a first waveguide  100  to the waveguide or optical fiber  46  of the probe  12 , which guides the light to the tip  42  where it is emitted for delivery to an area of tissue. In the particular embodiment shown, the light exits the waveguide  100  within the connector  86  and enters the lens  92 , which focuses the light into the waveguide or fiber  46  of the probe  12 .  
      Photosensitizing composition flows from its source  26  through a tube  78  and passage  104  of the connector  86  to and through the tunnel  50  of the tube  44  of the probe  12  for delivery to an area of the tissue. In the particular embodiment shown, the fluid flows from the passage  104  to and through the opening  56  in the member or tip  42  of the probe  12 .  
      In an alternative embodiment, it is contemplated that a member such as a tube may be connected to the source of therapeutic fluid and may be separate from the members used for delivery of light and/or sonic energy. In such an embodiment, the therapeutic fluid may be applied to tissue and then a probe including both a waveguide and a sonic scaling tip may be employed to provide light and sonic energy to the tissue.  
      In the illustrated embodiment, electrical energy is typically provided via a bus  110  (e.g., a wire or other electrical conductor) to the electrically conductive material  98 , which in turn creates a magnetic field for exciting the actuator material  60 . The actuator material then vibrates at an ultrasonic frequency and, in turn, vibrates the scaler tip  42  at an ultrasonic frequency.  
      It is additionally contemplated that the apparatus  10  may include a source  28  of cooling and/or lavage fluid (e.g., coupling fluid, water or saline) that can flow the fluid to and through the probe for delivery of the fluid to an area of tissue. In the particular embodiment shown, fluid is delivered through a tube  78  and a passage  112  in the connector and is delivered to a passage  114  defined within the probe  12  between the conductive material  98  and the actuator material  60 . The fluid is then delivered to the scaler tip  42  and emitted to the area of tissue. It is particularly preferred, but not required, for the sonic energy to be provided to the tissue in the presence of such cooling and/or lavage fluid.  
      It is additionally contemplated that the cooling and/or lavage fluid, the photosensitizing composition or both may include one or more additives, which can provide therapeutic advantages. For example, the cooling and/or lavage fluid, the photosensitizing composition or both may include bubbles (e.g., microbubbles) trapped in shells for enhancing acoustic cavitation, sonoluminescence or both when the probe is used to perform sonophotodynamic therapy. These bubbles can be produced using art-disclosed means such as the use of hydrocarbons, fluorcarbons, perfluorochemicals, sulfur hexafluoride etc. The addition of bubbles with gas in them (e.g., air, nitrogen, helium, argon, xenon, or the like) has been reported to emit light at higher intensity during sonoluminescence. The size of the bubbles is optimized to have a natural resonance at the frequency of sonic energy employed. The frequency resonance of a gas bubble (fr) is known to be approximately related by the following equation: fr=(3gPo/r) 1/2 /(2πa) where: g=the ratio of specific heats for a bas bubble, Po=ambient hydrostatic pressure, r=density of the surrounding media, and a=radium of the bubble in meters. Producing acoustic cavitation and sonoluminescence with lower applied acoustic intensity (e.g., tip vibration in the KHz ranges) is generally desired because of the potential problems with high intensity acoustic energy and non desired tissue effects.  
      It is also contemplated that gas (e.g., air, nitrogen, helium, argon, xenon, or the like) may be provided from the gas source  24  to any of the tunnels, openings, passageways or the like for purging or other purposes.  
      As suggested, the system apparatus  10  of the present invention may be employed for performing sonophotodynamic therapy upon a variety of tissue of nearly any organism, but that, the apparatus is particularly suited for performing dental sonophotodynamic therapy.  
      iii. Alternative Embodiments  
      As suggested previously, the members and other components of the apparatus of the present invention may be arranged, integrated and connected to each according to a variety of protocols within the present invention. As such,  FIGS. 6-9A  illustrate alternative embodiments of probes suitable for use with the apparatus of the present invention. As the skilled artisan will recognize, the members and components have similarities in structure and use as compared to previous embodiments. As such, only differences are typically discussed, however, previous descriptions of similar or same components and uses thereof apply to the following embodiments as well.  
      In  FIGS. 6-8A , there is illustrated a probe  120  having a base or proximal portion  122  and an attachment  124  that attaches to the base portion  122 . Referring to  FIGS. 8 and 8 A, the attachment  124  includes a housing portion  130 , a member shown as a scaling tip  132  for delivery of ultrasonic energy and a section  134  of a member shown as an optical fiber  136  for delivery of light. The attachment  124  has an actuator material  138  located within and substantially coextensive with the housing portion  130 .  
      The probe  120  preferably includes a member such as a tube  144  for delivering photosensitizing composition to and through the scaling tip  132 . The optical fiber  136  is located within and extends along a wall  146  of the housing portion  130 . As such the fiber  136  is substantially coextensive with the actuator material  138 . In the embodiment shown, the fiber  136  extends outward from the housing portion  130  and is arced to emit light toward the scaling tip  132 . It may be desirable to provide a protective encasing  150  about at least the end  152  of the section  134  of fiber  136 . The attachment  124  is also shown to include a covering  158  for protecting a linkage portion that connects the actuator material  138  to the scaler tip  132 .  
      With reference to  FIGS. 6, 7  and  7 A, the base portion  122  of the probe  120  includes a housing portion  160  and an electrically conductive material  162  (e.g., a magnetostriction driving coil) extending therefrom. The conductive material  162  is generally circular for defining a hollow portion  166  within the material  162 . The housing portion  160  includes a section  170  of waveguide shown as optical fiber.  
      Upon attachment of the attachment portion  124  to the base portion  122 , the section  134  of waveguide of the attachment portion  124  aligns with the section  170  of waveguide of the base portion  122  such that light can be transmitted down the lengths of the sections to the end  152  of the member or completed waveguide  180 . Also upon attachment, the actuator material  138  is located in the hollow portion  166  of the conductive material  162  such that the actuator material  138  may be sonically vibrated as previously described.  
      In another alternative embodiment and with reference to  FIGS. 9 and 9 A, a probe  200  similar to the probe  120  of  FIGS. 6-8A  is illustrated with the exception that the probe  200  includes two waveguides  202 ,  204 . As shown, the waveguides  202 ,  204  are on opposite sides of the probe  200  and have ends  210 ,  212  that emit light in generally opposite directions, but both toward a scaling tip  216  of the probe  200 . It will be understood that, at least in one embodiment, each of the waveguides  202 ,  204  could be configured similar to the waveguide  180  of  FIGS. 6-8A  and that additional waveguides or fibers could be added to the probe in a similar manner.  
      It is additionally contemplated that any of the fluids may be separately delivered rather than through the probe. For example, a syringe or a tube and pump assembly may be employed to deliver photosensitizing composition, cooling or lavage fluid or air or other gasses and then the probe may be used at the location of delivery of the fluid.  
      Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components can be provided by a single integrated structure. Alternatively, a single integrated structure might be divided into separate plural components. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention.  
      III. Sonophotodynamic Therapy  
      Referring to  FIG. 10 , the present invention provides a method  100  of killing microbes in the oral cavity comprising: applying a photosensitizing composition to a locus  102 ; applying a fluid (that is not the photosensitizing composition) and sonic energy to the locus  104 ; and irradiating the locus with a light at a wavelength absorbed by the photosensitizing composition so as to destroy microbes at the locus  106 . The sequence of these steps ( 102 ,  104 ,  106 ) may vary as long as the irradiating step  106  occurs during or after the photosensitizing step  102 . For example, in one embodiment of the present invention, the sonic energy step occurs after the other two steps ( 102 ,  106 ). In another embodiment, all three steps ( 102 ,  104 ,  106 ) occur at or near the same time. Furthermore, one of more of these three steps ( 102 ,  104 ,  106 ) can be repeated for the treatment of each locus.  
      The light applied during the irradiating step  106  can be supplied by a single light emitting device or a plurality of light emitting devices. Any suitable art-disclosed light emitting device(s) such as lasers, light emitting diodes (“LEDs”), arc lamps, incandescent sources, fluorescent sources, gas discharge tubes, thermal sources, light amplifiers or the like may be used to provide the wavelength(s) that can be absorbed by the photosensitizing composition. Lasers include any art-disclosed lasers such as diode lasers, gas lasers, fibers lasers or diode pumped solid state laser or the like. LEDs include any art-disclosed LEDs such as semiconductor LEDs, organic LEDS or a combination thereof. Fluorescent sources include any art-disclosed fluorescent sources such as fluorescent tubes, LED pumped fluorescent devices, cold cathode fluorescent panels or the like. Light amplifiers include devices that produced an amplified amount of input light (e.g., fiber amplifiers, gas amplifiers, etc.) or devices that produce wavelength shifted version of incident radiation or harmonics of incident radiation.  
      The light applied during the irradiating step  106  provides the wavelength(s) that can be absorbed by the photosensitizing composition. Such wavelength(s) include wavelengths selected from the continuous electromagnetic spectrum such as ultra violet (“UV”), visible, the infrared (near, mid and far), etc. The wavelengths are generally preferably between about 160 nm to 1600 nm, more preferably between 400 nm to 900 nm, most preferably between about 500 nm to 850 nm although the wavelengths may vary depending upon the particular photosensitizing compound used and the light intensity.  
      Referring to  FIG. 11 , the present invention provides a method  200  of killing microbes in the oral cavity comprising: applying a photosensitizing composition to a locus  202 ; and applying sufficient sonic energy to the locus in order to provide sonoluminescence at a wavelength absorbed by the photosensitizing composition so as to destroy microbes at the locus ( 204 ).  
      For methods  100  and  200 , the time required for each of the steps ( 102 ,  104 ,  106 ,  202 ,  204 ) on a locus may vary depending on the existing conditions (e.g., the microbes, the photosensitizing composition, the amount of calculus and plaque, the sonic energy source, the light source, etc.). For example, in one embodiment of the present invention, the time for completion of each of these steps may range preferably from about 1 second to about 1 hour, more preferably from about 1 second to 10 minutes and most preferably from about 1 second to 5 minutes. It is preferred that the photosensitizing composition is left in contact with the locus for a period of time to enable the microbes located near or at the locus to take up some of the photosensitizing composition and become sensitive to it. A suitable duration will generally be from about 1 second to about 10 minutes, preferably about 5 seconds to about 5 minutes, more preferably about 10 seconds to about 2 minutes and most preferably about 30 seconds although this may vary depending upon various factors such as the particular photosensitizing composition used, the target microbes to be destroyed, the reaction time required for any other compound(s) that may be added into the photosensitizing composition, etc.  
      The photosensitizing composition of the present invention is not limited to the use of one photosensitizer during the sonophotodynamic therapy. Depending on the desired application, multiple and/or different photosensitizers can be used simultaneously or separately during such therapy. The photosensitizing composition is preferably in a fluid form and the amount or concentration of the photosensitizer(s) contained in the photosensitizing composition may vary depending upon the desired application, the particular photosensitizer(s) used, and the target microbes to be destroyed. In one embodiment of the present invention, the concentration of the photosensitizer(s) is preferably from about 0.00001% to about 50% w/v, more preferably from about 0.0001% to about 25% w/v, still more preferably from about 0.001% to about 10% w/v, and most preferably from about 0.01% to about 1% w/v. Furthermore, the photosensitizing composition may comprise addition components such as pharmaceutically compatible carriers (e.g., solvent, gelling agents or the like), buffers, salts for adjusting the tonicity of the solution, antioxidants, preservatives, bleaching agents, antibiotics, or the like.  
      The sonic energy can be applied at any suitable art-disclosed level using any suitable art-disclosed devices such as a conventional dental scaler. For a list of exemplary dental scalers, see Introduction to Automated Scaler Comparison (Comparison of 16 Ultrasonic and 7 Sonic Scalers), June 1998 CRA Newsletter (Vol. 20, Issue 6), which is hereby incorporated by reference. It is preferred that the tip vibration of the sonic device is between the range of about 3 KHz to about 5 MHz, more preferably between about 20 KHz to about 3 MHz, and most preferably between about 25 KHz to about 1 MHz.  
      The methods ( 100 ,  200 ) of the present invention are useful for many purposes including, but is not limited to, (a) destroying disease-related microbes in a periodontal pocket in order to treat chronic periodontitis; (b) destroying disease-related microbes in the region between the tooth and gingiva in order to treat inflammatory periodontal diseases; (c) destroying disease-related microbes in the pulp chamber of a tooth; (d) destroying disease-related microbes located at the peri-apical region of the tooth including periodontal ligament and surrounding bone; (e) destroying disease-related microbes located in the tongue; (f) destroying disease-related microbes located in soft-tissue of the oral cavity; (g) disinfecting drilled-out carious lesions prior to filling; (h) sterilizing drilled-out carious lesions prior to filling; (i) destroying cariogenic microbes on a tooth surface in order to treat dental caries; (j) destroying cariogenic microbes on a tooth surface in order to prevent dental carries; (k) disinfecting dental tissues in dental surgical procedures; (l) disinfecting gingival tissues in dental surgical procedures; (m) sterilizing dental tissues in dental surgical procedures; (n) sterilizing gingival tissues in dental surgical procedures; (o) treating oral candidiasis in AIDS patients; (p) treating oral candidiasis in immunocompromised patients; and (q) treating oral candidiasis in patients with denture stomatitis.  
      The apparatus and the methods ( 100 ,  200 ) of the present invention discussed above also can be use for destroying disease-related microbes in wounds in other parts of the body (i.e., not just in the oral cavity) and disinfection of such wounds. In fact, it is believed that the present invention can promote wound healing. For such treatments of wounds, the apparatus and the methods described above would be the same except that instead of “locus” within the oral cavity, the methods would involve a wound.  
      The preferred embodiment of the present invention has been disclosed. A person of ordinary skill in the art would realize however, that certain modifications would come within the teachings of this invention. Therefore, the following claims should be studied to determine the true scope and content of the invention.  
      IV. Example  
      The present invention will be illustrated by the following example. This example is not intended to limit the scope of the present invention in any way.  
       E. coli  ATCC 25922 at a concentration of 1×10 6  CFU were put in a ˜0.5 ml well (TiterTek 96 well plate) with 50 ug/ml methylene blue (CAS number 61-73-4) in sterile water. Laser light at a wavelength of 670 nm was applied through a 200/240 micron cleaved optical fiber positioned so that light was emitted from the fiber and impinged upon the surface of the well at measured distances above the well. The light output of the cleaved fiber for each run was measured with an optical wattmeter. The spot size of the main beam at the surface of the fluid in the well was estimated by measuring the diameter of the brightest region with a scale then calculating the area from this diameter. Further, the intensity in the spot was calculated by dividing the measured power by the area of the spot.  
      Sonic energy was produced by a Parkell Turbo Sensor Ultrasound Scaler (25-30 KHz) with a Cavitron 30 KHz periodontal scaler insert (FSI-SLI). The power control on the unit has a low, medium, and high setting. These settings have peak to peak tip vibratory displacement amplitude in air of 34, 74, and 86 micrometers respectively. See Introduction to Automated Scaler Comparison (Comparison of 16 Ultrasonic and 7 Sonic Scalers), June 1998 CRA Newsletter (Vol. 20, Issue 6). A cylindrical wave emitted from a 1 mm diameter, 30 kHz vibrating wire at these peak-to-peak displacements would produce an emitted power, in air, per 1 cm wire length of 0.14, 0.48 and 0.85 watts respectively (utilizing equation 7.3.5, PM Morse &amp; KU Ingard&#39;s  Theoretical Acoustics [ 1968, McGraw-Hill, pp 358]) If this same amplitude of vibration was achieved in water, the emitted power would be 5.1, 18.5, and 32.7 W/cm respectively. Since a length of only about 2 mm of the tip would in fact be vibrating at the measured amplitudes, it is estimated that in air 0.028, 0.098, and 0.17 Watts, respectively, would be emitted at those displacements. In water, an estimated 1.0, 3.7, and 6.54 Watts would be emitted for the 2 mm tip length at those displacements. The relative amplitude of sound generated at the low, medium, and high settings in water were measured with a small microphone (Radio Shack Model No. 33-3028) covered with a latex membrane held at 3 mm from the vibrating tip under water. The RMS voltage amplitudes measured were 3.3, 5.7, and 10 volts at the respective settings. The square of these amplitudes is related to power being radiated. The square of each voltage reading provides 11, 32.8, and 100.8 V 2 , respectively. A plot of the square of these microphone measurements compared to the calculated emitted power (based on the peak-to-peak tip vibratory measurements) is shown below, demonstrating fairly a proportional relationship between the expected emitted power in water, given the tip displacements and emitted power estimated from microphone measurements. This result indicates the equipment used in this study was operating in a proportional manner to that as reported in the literature. 
 
 
      Each trial was conducted with a new well containing the suspension of bacteria and dilute photosensitizer solution. The ultrasound tip was sterilized by gently agitating the tip in Sporicidin® solution for 30 seconds per manufacturer&#39;s recommendations between each trial. Four trials were conducted for each exposure condition. The ultrasound tip was placed about 3 mm into the solution in the well for each trial. Exposures of light with no applied sonic energy and exposures with sonic energy and light were made. Time of exposure was standardized to 30 seconds per trial. The power control of the Parkell Turbo Sensor Ultrasound Scaler was set at the medium setting.  
      Results with light and sonic energy:  
                                                       Optical Intensity   Optical Intensity   Optical Intensity   Optical Intensity               14 mW/cm 2 ,   282 mW/cm 2 ,   478 mW/cm 2 ,   3,184 mW/cm 2 ,           Sonic Energy On   Sonic Energy On   Sonic Energy On   Sonic Energy On           50 □g/ml   50 □g/ml   50 □g/ml   50 □g/ml           Methylene Blue,   Methylene Blue,   Methylene Blue,   Methylene Blue,   Butterfield&#39;s       Test condition   pH 7.31   pH 7.31   pH 7.31   pH 7.31   buffer control                  Replicate counts   5.10E+05   1.00E+05   6.30E+03   5.80E+03   2.40E+06           1.20E+06   3.70E+05   4.00E+04   1.00E+01   2.10E+06       (Average of   1.20E+06   7.80E+05   2.40E+04   &lt;100**   2.30E+06       duplicate plates   7.50E+05   9.80E+05   6.80E+03   2.00E+02   2.30E+06       in CFU/ml*)       Average count in   9.2E+05   5.6E+05   1.9E+04   2.0E+03   2.3E+06       CFU/ml                 *CFU/ml refers to colony forming units per ml.            **Due to low sample volume exact counts could not be calculated. Replicate was excluded from            analysis.             
 
      Results with light alone without sonic energy:  
               TABLE 2                          Efficacy of Photocidex without Ultrasound against  E. coli  ATCC 25922                                     Optical Intensity   Optical Intensity   Optical Intensity   Optical Intensity           14 mW/cm 2 ,   282 mW/cm 2 ,   478 mW/cm 2 ,   3,184 mW/cm 2 ,           Sonic Energy Off   Sonic Energy Off   Sonic Energy Off   Sonic Energy Off           50 □g/ml   50 □g/ml   50 □g/ml   50 □g/ml           Methylene Blue,   Methylene Blue,   Methylene Blue,   Methylene Blue,       Test Condition   pH 7.31   pH 7.31   pH 7.31   pH 7.31               Replicate counts   1.20E+06   8.60E+05   1.00E+06   1.40E+05           9.80E+05   6.00E+05   8.40E+05   1.00E+05       (Average of   1.10E+06   1.10E+06   1.20E+06   9.70E+04       duplicate plates   7.70E+05   1.00E+06   1.00E+06   4.40E+04       in CFU/ml)                  
 
      Comparing the results of with and without sonic energy:  
                                                   Optical Intensity   Optical Intensity   Optical Intensity   Optical Intensity           14 mW/cm 2     282 mW/cm 2     478 mW/cm 2     3,184 mW/cm 2             50 □g/ml   50 □g/ml   50 □g/ml   50 □g/ml           Methylene Blue,   Methylene Blue,   Methylene Blue,   Methylene Blue,       Test condition   pH 7.31   pH 7.31   pH 7.31   pH 7.31                  Ratio of with/without   0.92   0.63   0.019   0.02       Sonic Energy                  
 
      As shown above, without ultrasound there was no significant killing of bacteria with light intensities of 14 mw/cm 2 , 282 mw/cm 2  and 478 mw/cm 2 . However, with ultrasound present at these light intensities, the surviving bacteria decreased respectively, 0.92, 0.63, and 0.19 compared to the results with no ultrasound. Furthermore, when the light was increased to 3,184 mw/cm 2  there was a significant amount of bacteria killed by only the light and photosensitizer. In spite of this, with ultrasound on at these optical intensities, more bacteria were killed (0.02 less bacteria survived than when no ultrasound was on). These results demonstrate that there is a synergistic effect of ultrasound, light and photosensitizer in killing bacteria.