Ultrasonic Home Dental Instrument And Method

Abstract

A method and apparatus for hygienic care of the oral cavity for regular use in the home, in which an ultrasonic applicator is used for cleaning of teeth as by the removal of tartar, placque, calculus deposits, stubborn stains, such as are produced by smoking, and simultaneous stimulation of the gingiva or gums. The ultrasonic applicator or stimulator has a polishing effect when used with a liquid medium and in engagement with the tooth and gingival structures of the oral cavity for the removal of foreign substances from the teeth.

Parent Case Text

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of my copending application Ser. No. 722,313, filed Apr. 18, 1968, now U.S. Pat. No. 3,547,110, dated Dec. 15, 1970, entitled Method and Apparatus For Maintaining Tooth and Gingival Structures with Ultrasonic Energy, which entire subject matter of the copending application is incorporated herein by reference as if fully herein set forth.

Description

BACKGROUND OF THE INVENTION

This invention relates generally to the hygienic care of the oral cavity, and more particularly to methods and apparatus utilizing ultrasonic vibratory energy for removal of foreign substances from teeth, polishing selected tooth surface areas, and the treatment of the gingival tissues within the oral cavity.

Applicant has already participated in earlier developments in ultrasonic periodontal applications which have led to U.S. Pat. Nos. 3,075,280, 3,076,904 and 3,213,537; and U.S. Pat. No. 3,375,820 of Balamuth and Kuris issued Apr. 2, 1968, for Methods and Apparatus for Ultrasonic Cleaning of Teeth and referred to as generally the "ultrasonic toothbrush." This latter invention may be used in conjunction with ultrasonic brush heads as disclosed in U.S. Pat. No. 3,335,443, issued Aug. 15, 1967, to Parisi et al.

We are concerned in the present invention with new discoveries by applicant which allow dramatic improvements in the application of ultrasonic energy for periodontal procedures, primarily for use in the home. Before proceeding to the details of the invention, let us first review briefly generally known facts of oral hygiene. Let us first look at the oral cavity with its tooth structure and gingival surfaces formed by the gum structure and review the situation as to objectives to be achieved. In the first place, ordinary tooth brushing uses bristles and toothpaste to keep tooth surfaces clean and hopefully, polished and bright (including "whiteness"). In addition, an attempt is made to clean out interproximal, gingival crest, or gumline areas, and other hard-to-get-at areas (without too much success). Finally, under dental teaching, the tooth brusher learns how to stroke the gingival-tooth boundaries so as to provide some gum stimulation. The now successful electric vibratory, i.e., 60 cycle per second, toothbrushes attempt to meet all the above goals, only with more efficiency and with the aid of outside electrical energy to aid the bristle motions during use.

There has recently come into general use a basic modification of the so-called Stim-U-Dent as a new kind of home periodontal care as an assist to the professional care ordinarily supplied by the dentist. As is probably well known the Stim-U-Dent is essentially a solid, narrow, elongated element (originally in wood) capable of being manually slipped interproximally of the teeth and then gently pressed up and down on the interproximal gingival surface. This provides gross local stimulation of gingival tissue by means of a macromassage and has been recognized even to the extent that toothbrushes are made with a brush at one end and a rubber tip at the other, the latter being used for the macromassage of gingiva. There are also stimulators which provide, instead of bristles at the brush end, several soft rubber suction cups, and also provide the rubber tip stimulator at the other end. The suction cup end also provide a means of applying pull-push massage forces to gums in noninterproximal areas such as the front and rear surfaces of the gums. Thus, quite apart form the present oral hygiene devices, such as manual and mechanical toothbrushes and water jet pulse generator, there exists the use of soft and hard gingival stimulators.

Now applicant has discovered that the addition of high-frequency mechanical vibrational energy to such elements as Stim-U-Dents, abrasive-filled Stim-U-Dents, and to soft suction-type applicators, permits the extension of benefits in oral hygiene normally obtained from the dentist, to safely self-administered benefits by the patient at home. As is usual with high-frequency mechanical vibration devices the benefits are multivalued comprising the possibilities of micromassage, fatigue destruction of calculus, interproximal cleaning due to cavitational energy in associated fluids being present, etc.

OBJECTS OF THE INVENTION

An object of the present invention is to provide improved methods and apparatus for performing oral hygienic procedures with ultrasonic energy.

Another object of the present invention is to provide novel and improved cleaning techniques for personal oral hygienic care which enables the user to control and obtain significantly better cleaning of teeth.

Another object is to provide new and novel methods and apparatus which are embodied in a device that is completely safe for use by adults and children in the home on a regular basis.

Another object of the present invention is to provide new and novel methods and apparatus for regular personal oral hygienic care which provides excellent cleaning results in the hard to reach interproximal and gumline areas in general, and simultaneous gum stimulation.

Another object of the present invention is to provide improved cleaning techniques for the removal of placque, tartar, calculus, stubborn stains, interproximal soft debris by a microfatiguing action.

Other objects and advantages of this invention will become apparent as the disclosure proceeds.

SUMMARY OF THE INVENTION

The present inventor has discovered that an important advance in the art is obtained by vibrating an applicator having certain characteristics to effect a polishing action on the tooth structure for performing home dental prophylaxis care by the user. The applicator is generally applied in the field of a fluid medium to both flush away the plaque, tartar (calculus) and stubborn stains, removed as well as provide a cooling action.

Specifically, applicant discloses a hand stimulator, of plastic or other material, in elongated slim pointed shape and containing incorporated removing means in the form of abrasive fine enough to polish dentine or enamel, but not coarse enough to abrade same. The stimulator being removably attached to a high-frequency mechanical vibrator motor, and at the same time with means to allow the constant presence of adequate cooling moisture at the side where the high-frequency rubbing is occurring. The moisture is to guarantee that the temperature of the treated area is continually in the neighborhood of ordinary tooth temperatures while the frictional rubbing occurs.

The practicability of this method of treating tooth structure prophylactically inheres in the fact that the main work of treating the tooth (or gingiva) is provided by the high-frequency energy and therefore, all the patient has to do is hold the applicator removing means in the proper position. Best results are obtained in specific cases by having the patient instructed by his/her dentist as to the best procedure to follow. Check up with the dentist guarantees that the safe home regimen is being carried out properly. Furthermore, the use of plastic stimulators and the avoidance of extra hard loose abrasives is combined with low levels of vibration in the home prophylactic device so as to ensure complete safety in use.

BRIEF DESCRIPTION OF THE DRAWINGS

Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof wherein like reference numerals refer to like parts throughout the several views and in which:

FIG. 1, is a perspective view of an ultrasonic oral hygiene unit embodying the present invention;

FIG. 2, is a section through the supply means of FIG. 1 taken along the lines 2--2;

FIGS. 3 and 4, illustrate the applicator means of the present invention in relation to the gingival and tooth structures of a human to obtain a cleaning action, and are helpful in explaining the operation of the present invention.

FIG. 5, illustrates the applicator instrument in accordance with the present invention in which the combination of polishing and fluid flow is employed;

FIG. 6, is an assembled view, partly in cross section, of the ultrasonic cleaning instrument according to the present invention;

FIG. 7, is a sectional view through the ultrasonic handpiece of FIG. 6, taken along the line 7--7;

FIG. 8, is a sectional view of an applicator in accordance with the invention;

FIG. 9, is a sectional view of another form of applicator insert in accordance with the invention; and

FIGS. 10 and 11, illustrate modified applicator constructions.

DETAILED DESCRIPTION OF THE DRAWINGS

Turning now to FIGS. 1 and 2 there is illustrated an oral hygienic unit 10, which will be described in greater detail hereinafter, and for present purposes it is sufficient to indicate that it includes an instrument or handle means 12 adapted to be held by the user in a conventional manner, having extending from one end thereof supply means 14 which supplies to the instrument means 12 both power and a constant supply of fluid. Applicator means 16 extends from the opposite end of the instrument means 12 and has a passageway extending therethrough and in communication with the supply means 14 to permit the formation of a stream of liquid 15 of a small cross-sectional area, generally in the diametrical range of 0.010 inch to about 0.070 inch. The fluid generally in the form of a liquid is passed through the instrument means 12 to exit at or near the applicator means 16.

The velocity, and spray pattern fluid stream 15 may be controlled by employing pumping means 20 which continuously supplies liquid 21 from the reservoir means 22, either continuously or intermittantly. Generating means 24 is provided to convert the current, i.e., 60 cycle, to a frequency in the ultrasonic range, which for purposes of the present invention, "ultrasonic" is defined to include the range of approximately 5,000 cycles per second to 1 million cycles per second, although preferably in the range of approximately 16,000 cycles per second to 40,000 cycles per second. The oral hygienic unit 10, may be controlled such that the liquid stream may be continuously pumped at a constant rate of flow with the ultrasonic energy transmitted thereto, or the liquid stream may be simultaneously pumped to obtain a macropulsing action as well.

To power the unit 10 we have a plug 27 and cord 28 which is in communication with the generator means 24 and pumping means 20. Switching means 26 contains a first switch 30 connected to the generator 24, in a conventional manner, for providing power for energizing the ultrasonic motor contained within the instrument casing 32 of the hand held instrument means 12. The energy from the generator is transmitted to the ultrasonic motor by wires 33 and 34 extending through the flexible conduit 35 of the supply means 14.

A second switch 31 is provided to control the pumping action of the liquid supply, such that both the velocity as well as the pumping cycle is controlled. Although reservoir means 22 has been shown in communication with the pumping means 20, it is to be understood that essentially both might be considered the equivalent of a water tap under normal pressure that is controlled as to volume by the conventional control of the faucet, found in the home. But to obtain controlled velocities of the fluid stream it is preferable to provide both reservoir and pumping means. The switch 31 is provided to regulate, in any conventional manner, the pumping means 20 to provide a stream of the fluid 21 through the tube 37 which is contained in the conduit 35, through the ultrasonic motor and then exiting from the applicator means 16 in the direction of arrow 38 in the form of a pattern or stream 15. The applicator means 16 may take various shapes and forms to permit its positionment within the oral cavity and is coupled to the ultrasonic motor to induce therein ultrasonic energy waves in the direction of double-headed arrow 40. A more detailed discussion of the ultrasonic dental unit 10 is contained in U.S. Pat. No. 3,547,110 and may be referred thereto for one form of construction thereof.

As seen in FIG. 1 the dental applicator or stimulator means 16 has a contoured tip 23 that may be pointed for proper positionment within the oral cavity and contains removing or polishing means 25 thereon. The solid removing plastic stimudents 16 may have incorporated into them the means 25 in the form of a very fine abrasive 29 so that a rubbing action against tooth structure permits the slow removal of plaque and calculus from teeth as well as the polishing of tooth surfaces after such removal. These plastic elements 16 may be used by dentists to perform what is called "port polishing" of root surfaces of teeth, a sophisticated dental procedure whose aim is to render the polished surfaces so smooth that the buildup of placque and subsequent development of calculus is inhibited. The applicator 16, removing means 25, is intended for interproximal placement and action therein to remove placque and calculus and also to polish tooth surfaces where such foreign deposits have been removed. The pointed shape 23 of the applicator 16 gives maximum flexibility in being able to reach relatively inaccessible interproximal areas. The placement of the orifice 74 for water exit is such that surface at the tip 15 of the applicator may serve as an atomizing means so that the treated area is being continually saturated without there being a need for an excessive water flow. However, this arrangement is not the only usable one to practice the invention. For example, the plastic applicator could be provided with an adjoining flow section, as hereinafter illustrated, which serves to bring coolant in adequate amounts to the treatment site.

The polishing particles 29 may be of various commercial materials that are known to be capable of engagement with the tooth structure without damaging effects when properly used. For example, zirconium silicate, calcium bentinite, aluminum oxide, flour silicon, rouge, silicon carbide, boron carbide, cerium oxide and Tripoli powder may be selected for use at a size and level for polishing without scratching. The particles 29 may be embedded within, or bonded to, the applicator 16 which may be made of plastic, paper or other material such as metal. In addition, the applicator 16 may be formed entirely or on a core, and the polishing medium sintered or otherwise bonded together to be maintained and vibrated at a given level of mechanical vibratory energy to perform the results described herein. Although the particles 29 are illustrated on the drawings to be of a size visible to the eye, it is appreciated that in actual fact the mere viewing of the applicator would not necessarily disclose to the naked eye that it has the particles 29 thereon.

In accordance with the present invention, as is illustrated in FIGS. 3, 4, and 5 the applicator means 16 of the hand held instrument is positioned within the oral cavity and in substantial engagement with the tooth structure 45 and/or the gingival structure 46 for interproximal gum line, and other treatment thereof. That is, the applicator is inserted in the mouth and positioned adjacent the desired structure to be treated with the mechanical vibrating energy in such a manner to engage the various portions of the oral cavity. The treating applicator 16 is manually moved over the respective tooth and gingival surfaces 48 and 49 respectively, much in the manner in which conventional brushing is performed. The fluid stream 15 which is generated by means of the pumping means 20 is of a relatively small cross-sectional area and as the liquid is passed through the supply means 14, and in turn through the instrument means 12, high-frequency ultrasonic energy may be superimposed on the stream of liquid so as to obtain a micropulsing action thereon. Accordingly, the stream of liquid is then moved to substantially engage the tooth structure 45 or gingival structure 46, within said cavity and it is moved at such a rate, dependent upon the user, to obtain a microstimulating of the engaged structure by transmitting the ultrasonically micropulsed energy waves contained in the fluid stream 15 to effect a cleansing action thereof. In this manner a level of hygienic control may be maintained in the oral cavity.

Accordingly, the action obtained by the fluid stream in the form of microstimulation may be divided into various subcategories. Particularly, we have the ability due to a microfatiguing action of the polishing means 25 to remove foreign deposits, or substances 50, normally found on teeth which may be generally characterized as stain, placque, calculus or tartar. Stain and tartar are both adherent deposits on teeth but placque is somewhat softer and less adherent, such as soft food deposits found between or on the teeth. The ability of the applicator polishing means 25 to engage these hard foreign deposits brings about this microfatiguing action in such a manner such that the bond between the teeth structure and the foreign deposits is weakened by the high-frequency energy pulses to the extent that it is broken and the resultant deposits are flushed away by the continuous stream of liquid.

In this manner it has been shown that the ultrasonically vibrated applicator 16 with a continuous or pulsed fluid flow can remove tartar deposits. In addition it also removes stain and interproximal deposits in a significantly superior fashion, these improved cleaning results are believed to be directly related to the ability to continuously supply at an ultrasonic rate a polishing action to fatigue the bond between the tooth structure and foreign deposits to obtain the latters removal.

In addition the microstimulation concept also takes another form in its ability to remove tartar deposits by the well-known factors of a liquid combined with a grit, such as toothpaste or a special powder to also assist in removal of tartar and calculus. This is brought about since the applicator, which is ultrasonically vibrated produces various cavitational action in the area in which it is directed. This is directly related to the high-frequency acceleration which further enhances the cleaning action effect and will also assist in the removal of foreign deposits.

In order to obtain the desired removal effect it is just necessary to bring the vibratory surface removing means 25 of the applicator means 16 into lightly engaged contact with the surface of the structure to be treated and in the presence of the material removing particles 29 contained on the applicator. This may take the form of various particles 29 which may be embedded in the applicator.

Simultaneously with the results obtained by microfatiguing we simultaneously have the action obtained by micromassaging of the gum structure if desired, of the organic oral cavity. A jet stream may have superimposed on the ultrasonic vibrations in the range of from 5,000 to 1 million cycles per second and at the same time this stream might be simultaneously pulsed at a defined low frequency to obtain a macropulsing thereof. This low-frequency macropulsing is generally in the range of 6 cycles per minute to 26,000 cycles per minute. This permits a combination of effects to be obtained since the macropulsing has certain known beneficial aspects, and the micropulsing has others, which when combined produces results in the maintenance of the condition of the oral cavity not heretofore obtainable.

Accordingly, the combination of an ultrasonically vibrating applicator tip yields with a polishing compound provides an unexpected bonus of tooth treatment which is not present in other ultrasonic systems. Together with the other advantages arising from the combination described in this invention we have therefore transcended a simply additive combination and have arrived at a truely novel improvement in oral dental hygiene.

Having pointed out the benefits of the impregnated applicator with removing means it should be indicated that this direct coupling of the energy which is simultaneously transmitted through the applicator directly to the treated structure, may have a vibratory component either elliptical, longitudinal, torsional, or any combination thereof. As indicated in FIG. 5 means 52a, which includes a plurality of individual resilient Stim-U-Dent members coupled to the applicator means 16a for transmission of the mechanical vibrations. The advantages of utilizing the applicator means 16a in substantial engagement with the treated structure, irrespective if it is in the form of a single Stim-U-Dent which is essentially what is shown in FIG. 2 or a plurality of Stim-U-Dents each containing removing means 25a with particles 29a thereon, pertains to the basic configuration such that the contour of the teeth 48a is followed by the Stim-U-Dent 52a such that we obtain the combined effects in a manner to obtain the coupling or transmission of ultrasonic energy to the treated structure through substantial direct engagement of a solid member. The liquid medium 15a is directed at a predetermined pressure such that we are able to maintain the tooth structure at a desired temperature level and flush away the removed particles.

Utilizing the brushing implement of FIG. 5, the brush is inserted in the mouth of the user and moved across the gingival surfaces, so that the polishing means 25a is adapted, to engage both the tooth and gingival structures 45a and 46a, with the Stim-U-Dent or bristle cluster in relatively light contact with the tooth surfaces 48a and the gingival surfaces 49a as well. As the applicator implement 16a is manually moved throughout the mouth the liquid stream 15a is continually flowed thereagainst to simultaneously engage the desired surface structures and flush away removed particles. The individual Stim-U-Dent, or if a plurality of clusters are employed, they assume different positions and permit the removal of foreign deposits that are contained on the tooth surfaces or interproximal as indicated in FIG. 4. Thus, we have in effect a microfatiguing of the foreign substances by transmitting the energy waves contained in the removing means 25a against the tooth structure for a period of time to fatigue the bond between the tooth structure and the foreign deposits and effect the removal thereof.

We also have the ability, if desired, to obtain a micromassaging of the gingival structure by the ultrasonically micropulsed energy stream which pervasively penetrates and treats the structure for the use required. This dual effect obtained by the microstimulation, removes interproximal and gum line foreign substances as well as those adhering to the surfaces of the teeth as well. The rate of removal will be dependent upon the accumulation to date and whether or not the patient requires primarily gingival stimulation or removal of materials, in either case he moves the applicator means in the direction he so desires, or, preferably as advised by the dentist.

In order to practice the novel combination or methods discussed hereinabove, in a practical manner to accomplish the desired objectives, it is preferable to provide an ultrasonic motor of low cost, when mass produced; also, it is important to limit the amount of ultrasonic vibrational energy so that an over zealous user may not wear away the surface or damage the gum structure along with the stubborn stains or calculus. All the requirements cited above may be realized by using a suitable instrument including plastic, rubber, or other components which may be designed to be of self limiting vibrational energy transmitters which can deliver, and at the same time, which are also capable of delivering the continuous pulsating jet stream of liquid to the work site.

In FIGS. 6 through 11, there is shown various embodiments of ultrasonically driven instruments in accordance with the principles of the present invention. As seen best in FIGS. 6 and 7, the instrument means 12 comprises two basic elements, namely an applicator insert 53, and a handle unit 54 for receiving the insert 53 and which together form in part the ultrasonic motor means 18.

The pumping means 20 of the system produces a stream of liquid and the instrument means 12 forms a passageway 72 to transmit the stream of liquid by means of the applicator means 16 which has a continuing passageway therethrough for applying the jet stream 15 to the structure to be treated in the direction of arrow 38. The ultrasonic motor means 18 contained within the instrument means 12 can superimpose on the liquid stream mechanical vibrations in the ultrasonic range to form micropulsed energy waves therein. The generator means 24 may be set to provide rest periods by pulsing or modulating the energy waves at a frequency in the ultrasonic range. At the same time the pumping means 20 may be set to provide pulsing at a frequency less than the frequency of said micropulsed energy waves.

The outer casing 32 of the handle unit 54 of the instrument means 12 is generally of a cylindrical element preferably formed of an electrically insulating and fluid impervious plastic material, which is provided with a central bore 55 extending axially therethrough. The outer dimensions of the instrument means 12 is made such as to be comfortably held in the hand without causing fatigue.

The handle unit 54 is formed in two sections, a first section which is the outer casing 32 whose exterior surface forms the peripheral surface of the handle, and a second portion 57 including a tubular extension which fits within the member 32, leaving between the members an annular space extending substantially over their entire lengths. Within this annular space is wound a coil 56 of insulated wire for establishing the magnetic field. At the rearward end of the bore in the member 32 is formed a reduced diameter portion 58 sized to receive the applicator insert 53.

The conduit 35 of the supply means 14 is secured to the end of the instrument, as by applicator insert support means 62 having a radical flange 63 secured to the inner bore 54 in any conventional manner, and a rear lip 64 which has the tube 37 snugly fitting thereover. A front lip 65 retains the applicator insert 53 in position.

The applicator insert support means 62 contains a bore 66 to permit the supply means 14 to be in communication with the instrument means 12 and the passageway 72 extending therethrough. The front lip 62 is of a diameter to snugly fit within the end portion 67 of the applicator insert 53. The resiliency of the material used, such as plastic, in the acoustic element enables the applicator insert 53 to be manually forced over the front lip 65 by a force which is sufficient to prevent its voluntary release but which a child is capable of applying. Similarly, the applicator insert 53 may be removed from the instrument 12 with the proper amount of force and at the same time provide a fluid tight seal.

The complete assembly for use in the home includes the generating means 24, for example, a transistorized oscillator capable of producing electrical oscillation at a frequency in the ultrasonic range e.g., between 16,000 and 100,000 cycles per second. Various types of such oscillators are known and it is not believed necessary to describe the details herein.

Electrical oscillations and direct current from the source are coupled via the connector 27 (FIG. 1) and the lead 28, to the generator 24 and in turn through the leads 33 and 34 to the coil 56 in axial spaced relation to an acoustic element 70 in the instrument 12 which forms part of the insert 53. There is thus established in the bore 55 of the handle a magnetic field whose magnitude changes at an ultrasonic rate. Upon insertion of the applicator insert 53 the magnetostrictive portion of the acoustic element 70 is positioned within the magnetic field and in well-known manner provides a mechanical longitudinal vibration at the frequency of the magnetic field.

The illustrated embodiment of the applicator insert 53, as shown in partial cross section in FIG. 6, and which forms part of the ultrasonic motor 18, comprises a vibratory transmitting assembly which includes the vibratory or acoustic element 70 which is preferably made of a nonmetallic material such as plastic or glass etc., but is capable of transmitting and acting as an acoustic element to transmit the high-frequency vibratory energy. Secured to the exterior surface of the elongated acoustic element 70 and forming a part thereof, is a plurality of spaced-apart strips 71 running actually the length of the acoustic element core 70 which as hereinafter discussed when energized will vibrate and which vibrations may also be coupled to the applicator means 16 such that the latter vibrates and is capable of transmitting vibratory energy. In order to vibrate such thin metallic strips, such as Nickel from which the strips may be made, it is important that they be bonded to the acoustic element 70. For example, if the acoustic element 70 is of a plastic material in the form of a rod and in the preferred embodiment is illustrated to be hollow having a conduit or instrument passageway 73 extending therethrough, which forms part of the fluid flow passageway 72, and which carries the metallic strips or layers thereon. The metallic material may be bonded to the plastic by several available methods, including electroplating, epoxy bonding and the like. It is of course necessary to supply the Nickel coat in such a way that no complete rings or circles of metal are formed. This is to minimize eddy currents. Also it is possible to cut the tube which contains a suitable binder for binding both the support member and Nickel together to the underlying plastic. The acoustic element 70 could be glass for sanitary reasons and for high Q high-efficiency vibration. But if glass is used definite limitations must be inherent in the driving generator. The sidewall of the acoustic element 70 may also have bonded to it a piezoelectric or magnostrictive pickup element in order to keep the motor automatic in its resonant frequency operation.

In practice the generator may be as small as 1 to 10 watts into the ultrasonic motor, and is preferably of the solid state type. The forward end 75 of the acoustic element 70 is provided in the conduit 73 with a threaded portion 76 which is adapted to be engageable with the applicator means 16. The applicator means 16 includes an applicator member 80 which at its rear portion 81 is provided with a complimentary threaded portion 82 for engagement with the threads 76. As seen in FIG. 6, the applicator member 80 may include a forward portion 83 which is tapered with respect to the rear portion 81 of the applicator. The applicator member has an applicator passageway or conduit 74 continuing therethrough, and is hollow throughout its entire length to permit the liquid which is being passed through the instrument passageway 73 of the applicator insert 53 to continue in its path to the working or output surface 84 of the applicator means 16. The angular relationship between the forward portion 83 and rear portion 81 of the applicator member 80 will be dependent upon the amplitude of vibration of the output surface 84 as well as the configurations of the vibrational pattern desired to be obtained thereat.

Accordingly, the applicator insert 53 which has the fluid passageway 72 extending therethrough may be designed such that the acoustic element 70 is positioned in energy transferring relationship to the instrument passageway 73, so that the ultrasonic mechanical vibrations are continuously transmitted to the stream of liquid as it passes therethrough. The applicator means 16 includes the applicator passageway 74 extending therethrough and which is in communication with the instrument passageway 73, such that essentially the passageway 72 is formed by the instrument passageway 73, and the applicator passageway 74. Depending on the design of the ultrasonic system the energy waves may be introduced into the liquid stream in either of said passageways if desired or the water or other liquid brought to the applicator 16 at substantially the point of application.

Thus, one complete magnetostrictive system would include an acoustic element 70 comprising a properly coated tube member formed of any suitable material capable of supporting vibrations transmitted thereto from the magnetostrictive coating, this will include many metals and hard plastics which are suitable for this purpose. In order to operate most efficiently, the magnetostrictive strips 71, the associated body 70, and the applicator means 16 should together be resonant with the frequency at the applied electric current. A suitable material enabling the length of the acoustic element 70 to be maintained within reasonable limits is Nickel, but it will be understood that other materials may also be used.

As to a further construction of the applicator insert 53 the acoustic element 70 may also be made from Pyrex glass tubing. On the surface of this tubing a silver metallizing paint is baked on and then Nickel plating is placed on the metallized surface. Slotting of the Nickel coating is provided by masking the Pyrex tube surface during silver metallizing. This manufacture lends itself to automated mass production. The hollow tube output end of the glass tubing provides a means for attaching a light weight metal element to receive screw-on plastic or other working tips. The hollow tube also lends itself to through feed of liquid mediums. The coupling to the casing may be accomplished with O-rings or variants of other type mountings. Much simpler, of course, would be permanently attached working tips. In this case the whole insert must be inexpensive enough to be replaceable at suitable intervals by buying new ones. The plated glass tube-type transducer would lend itself pretty well to this type of approach.

Now, in addition to the complete system described we may include in the handle 54 into which the applicator insert 53 is assembled in addition to the energizing winding, pickup winding in the form of a permanent magnet (not shown) to bias the acoustic strips 71. Now, in addition to this we also have the hydraulic system which includes the reservoir means 22 and a suitable electric pumping means 20, which arrangement was previously discussed with respect to FIGS. 1 and 2.

Front support means for the applicator insert may include a radial flange in the form of an O-ring 85 which prevents the vibrations induced in the applicator insert 53 from being transmitted to the handle portion 54.

FIG. 8, shows applicator means 16a which includes Stim-U-Dent means 52a in the form of a flexible member 90a in spaced-apart relation and coupled to the applicator member 80a in any conventional manner. The applicator member 80a includes a rear portion 81a having threads 82a for securement to the acoustic element. The forward portion 83a is integral with the output portion 84a from which the flexible member 90a extend in a plane substantially normal thereto. The fluid passageway or conduit 74a tapers downwardly and terminates in a plurality of apertures 91a through which the liquid flows to form a plurality of spaced-apart flow patterns 15a between or in spaced relation to the removing means 25a having particles 29a thereon. In this manner the member 90a conforms to the contour of the teeth with the removing means 25a engaging various surfaces simultaneously.

FIG. 9 illustrates another embodiment of the applicator insert 53b that may be used in conjunction with the instrument illustrated in FIG. 6, in the illustrated embodiment, the applicator insert 53b comprises an elongated magnetostrictive acoustic element 93b formed of a plurality of thin sheets of a magnetostrictive material such as permanickel or permendur, or any other material capable of mechanically elongating or shortening when subjected to a magnetic field. In view of the relative dimensions of the magnetostrictive portion 93b, it will be seen that upon insertion in a suitably oriented magnetic field, a significant elongation of the stack will occur. Consequently, upon application thereto of a magnetic field whose magnitude varies, the length of the stack 93b will similarly vary. In accordance with known principles, the magnetostrictive stack 93b is made to be of a length equal to an integral number of half-wave lengths in the material at the driving frequency. In this manner, maximum conversion of energy from the magnetic field to mechanical vibration is achieved. As is noted hereinabove, other forms of electrical to mechanical transducers, e.g., piezoelectric, ferrites, and others may also be employed in accordance with the present invention.

Rigidly affixed to one end of the magnetostrictive element 93b, such as by welding, is a connecting member 94b. This member may be formed of any suitable material capable of supporting vibrations transmitted thereto from the magnetostrictive stack and many metals and hard plastics are suitable for this purpose. However, to operate most efficiently, the connecting member 94b should be made equal in length to an integral number of half-wavelengths in the material at the frequency of vibration. A suitable material enabling the length of the connecting member 94b to be maintained within reasonable limits is Monel, but it will be understood that other materials may also be used.

Preferably, the connecting member 94b is formed to produce at its output end 95b an amplification of the longitudinal vibrations applied to its input end by the magnetostrictive member 93b. To effect this function, the member 94b is formed in two sections 96b and 97b of differing diameter. The transition from the larger to the smaller diameter occurs at a nodal point of vibration, that is, a point along a member wherein longitudinal motion is a minimum. In a uniform diameter element one-half wavelength long, such a node would occur at the quarter-wave point, half way between the ends. By locating the transition point at a nodal plane, proper acoustic impedance transformation takes place and an increased longitudinal amplitude of vibration is obtained at the output end 95b.

The applicator member 16b is rigidly affixed to the forward end 95b of the connecting member such as by a screw threaded fastening. By this means, longitudinal vibrations in the connecting body may be transmitted unimpeded to the applicator means 16b and consequently to the removing means 25b mounted thereon.

Surrounding the magnetostrictive stack 93b and the connecting member 94b is a generally cylindrical casing 100b formed of a suitable nonmagnetic and fluid impervious material, such as plastic or aluminum. The casing 100b is structurally rigid and spaced from the peripheral surfaces of the stack 93b and connecting member 94b over substantially their entire lengths so as not to be vibrated therewith.

At the connecting member end of the casing 100b the walls thereof are somewhat thickened to closely engage the peripheral surface of the enlarged portion 96b of the connecting member. At approximately a nodal point of longitudinal motion in the connecting member, an annular insert 101b of rubber or similar resilient material is secured in the casing and extends therearound to snugly engage a mating depression provided in the surface of the connecting member 94b. This serves to firmly support the connecting member within the casing 100b in such a manner that no longitudinal vibration is transmitted to the casing 100b. The insert 101b and the closeness of fit between the casing 100b and the outer surface of the connecting member 94b also provide a fluidtight seal between the casing 100b and the connecting member 94b.

The end of the casing 100b beyond the magnetostrictive portion 93b is thickened at 102b and provided with an aperture 103b extending all the way through to receive the front lip 65b such that the liquid flowing therein enters the passageway 72b, which includes the passageway 73b, which is the space between the stack 93b and the inside of the casing 100b. The instrument passageway 73b continues exteriorly of the insert by means of a conduit 99b which connects at the insert 101b to a point adjacent the tip 23b so that a flow of fluid 15a is present at the work site and the applicator means 16a may be removed and a new one assembled as desired.

It will be seen that the entire applicator insert 53b is self-contained and includes only one part subject to wear, i.e., the applicator 16b, which is arranged to be removed without difficulty and replaced with a new unit whenever necessary.

FIG. 10 illustrates a form of the applicator means 16c in which the fluid 15c in spaced relation to a tip 106c thereof by a distance D. This permits the removing means 25c at the tip 106c to engage the tooth structure and provide a flow of cooling liquid. The fixed spacing between the output surface 84c and the tip 106c is important in that the fluid flow is not blocked by the user. In addition the flow may be so proportioned that a significant amount of atomization occurs at surface 84c, thereby assuring a continuous "rain" of liquid at the treatment site.

FIG. 11 illustrates a form of the applicator means 16d with Stim-U-Dent means 52d in the form of a suction cup provided such that the liquid flow 15d exits from the applicator means 16d in spaced relation to the engaged surface and into the cup formed by the Stim-U-Dent means 52d.

Accordingly, applicant has referred to the benefits arising from the energizing of a soft applicator, be it of suction cup type or a simple soft blunt element. In this case, as seen in FIG. 11 the applicator 16d in the form of a suction cup, may be used in its ordinary manual mode of hand push-pull to provide macromassage, but at the same time high-frequency energizing provides additional modes of periodontal home treatment. For example, applicant has found that as the soft elastic element is pressed against gingival tissue the ability of the element to transmit micromassage vibrations to the gingiva is increased. Thus during manual manipulation the applicator periodically causes a pulsing of micromassage energy to be added to the macromassage energy normally being applied. Now, at the same time by providing a small orifice 91d into the soft cuplike element 52d through which water may trickle we have an additional coupling medium interposed between the gingiva and the surface, which, as vibrating fluid medium assists in enhancing the micromassage effects.

The Stim-U-Dent 52d may also have removing means 25d with particles 29d thereon for engagement with the surfaces.

From the foregoing, it will be evident that the application of ultrasonic energy by employing cleaning means to tooth and gingival surfaces is effective to provide significantly improved cleaning action, and, if employed for regular dental care in the home, will result in maintenance of greater dental health than is possible utilizing conventional implements.

While the invention has been described in connection with particular ultrasonic motor and applicator constructions, various other devices and methods of practicing the invention will occur to those skilled in the art. Therefore, it is not desired that the invention be limited to the specific details illustrated and described and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.

Claims

I claim:

1. The method of removing foreign deposits from teeth comprising the steps of:

A. positioning adjacent the teeth to be cleaned an abrasive surface capable of supporting and transmitting ultrasonic vibrations,

B. inducing vibrations in said abrasive surface at a frequency in the ultrasonic range,

C. maintaining a film of fluid at the cleaning site of said abrasive surface, and

D. moving said ultrasonically vibrating abrasive surface relative to said teeth such that it engages and removes the foreign deposits therefrom and said fluid acts to maintain the cleaning site free of said removed foreign deposits.

2. The method as in claim 1, wherein said fluid is supplied at a temperature and rate to maintain said teeth at substantially a constant temperature during cleaning thereof.

3. The method as in claim 1, wherein said abrasive surface is nonscratching against said teeth.

4. The method as in claim 1, wherein said abrasive surface is flexible and adapted to substantially conform to the contour of said teeth.

5. The method as in claim 1, wherein said abrasive surface is in the form of a single pointed member adapted to be selectively positioned against and interproximally of said teeth.

6. The method as in claim 1, wherein said abrasive surface is in the form of a plurality of individual bristle elements each containing an abrasive surface thereon such that the elements assume positions in which they are randomly divided between actual contact with and displacement from the surfaces of said teeth.

7. The method as in claim 1, wherein said motion of said abrasive surface is of an amplitude of vibration to produce a cavitational action in said fluid film between said abrasive surface and said teeth surfaces when said abrasive surface is displaced therefrom.

8. The method as in claim 1, wherein said abrasive surface is vibrated in the frequency range of 5,000 cycles per second to 1 million cycles per second.

9. The method as in claim 8, wherein said frequency is preferably in the range of 16,000 cycles per second to 40,000 cycles per second.

10. The method as in claim 1, wherein the amplitude of vibration of said abrasive surface is in the range of 0.0001 inch to about 0.070 inch.

11. The method as in claim 1, and further including the step of providing a stream of fluid for maintaining said film at said cleaning site.

12. The method as in claim 11, further including the step of pulsing said stream of fluid at a preselected pattern of pulses at spaced intervals of time.

13. The method of removing surface, interproximal and gum lime foreign deposits from teeth in the oral cavity comprising the steps of:

A. inserting an applicator having an abrasive contacting surface within the oral cavity,

B. positioning said abrasive contacting surface adjacent the teeth to be cleaned for transmitting to the selected structure mechanical vibratory energy in the ultrasonic frequency range,

C. vibrating said abrasive surface at an ultrasonic rate,

D. maintaining the contacted surface of the teeth at substantially a constant temperature, by

1. generating a stream of liquid of small cross-sectional area,

2. pumping said stream of liquid to said contacted surface to maintain a fluid at the cleaning site, and

E. moving said ultrasonically vibrating abrasive surface relative to said teeth such that it engages and removes the foreign deposits therefrom and said fluid acts to maintain the cleaning site free of said removed foreign deposits, and at a substantially constant temperature.

14. The method as in claim 13, further including the step of pulsing said stream of fluid at a preselected pattern of pulses at spaced intervals of time.

15. The method as in claim 14, wherein the frequency of pulsing said stream is in the range of 6 cycles per minute to 26,000 cycles per minute to obtain a macropulsing thereof.

16. The method as in claim 14, wherein the frequency of pulsing said stream is in the ultrasonic frequency range.

17. The method as in claim 14, wherein

a. said stream of liquid is moved to substantially engage the gingival structure, and

b. further including the step of micromassaging of the cellular structure of said gingival structure by providing ultrasonically micropulsed energy waves in said stream for pervasively penetrating and treating the accessible inner region of said gingival structure for treatment thereof.

18. The method as in claim 13, further including the step of maintaining said stream exiting from said applicator, in spaced relation to said teeth.

19. The method as in claim 13, wherein said stream of liquid and applicator are vibrated at substantially the same frequency.

20. The method of removing surface, interproximal and gum line foreign deposits from teeth structures, and treating the gum structures, within the oral cavity for hygienic control thereof, with an applicator having an abrasive surface capable of supporting vibrations in the ultrasonic range and adapted to be inserted within the oral cavity, comprising the steps of:

A. inserting said applicator within the oral cavity,

B. positioning against the structures to be treated the abrasive surface of said applicator,

C. generating a stream of liquid of small cross-sectional area,

D. pumping said stream of liquid through said applicator, such that said stream of liquid substantially engages the teeth or gum structures thereof,

E. micropulsing said stream of liquid in said applicator to induce therein energy waves in the ultrasonic frequency range,

F. vibrating said abrasive surface at an ultrasonic rate against said teeth to effect a removal of said foreign deposits and a flushing away thereof by said stream of liquid,

G. microstimulating said engaged structure by transmitting said ultrasonically micropulsed energy waves contained in said stream to effect the treatment thereof,

H. pulsing said stream at a frequency below that of said micropulsing frequency to provide doses of mechanical energy at two different frequencies to said treated structure, and

I. moving said ultrasonically vibrating applicator relative to said teeth and gum structures for removing deposits and treatment thereof.

21. The method as in claim 20, wherein

a. said stream of liquid is moved to substantially engage said teeth and any foreign deposits adhered thereto, and

b. said microstimulating includes a microfatiguing of said foreign deposits by said vibrating abrasive surface and by transmitting said micropulsed energy waves contained in said stream against said teeth for a period of time sufficient to fatigue the bond therebetween and effect the removal of said foreign deposits therefrom, whereby the teeth may be maintained substantially free of foreign deposits.

22. The method as in claim 20, wherein

a. said stream of liquid is moved to simultaneously engage said teeth and gingival structures, and

b. said microstimulating simultaneously effects a micromassage of said gingival structure and a microfatigue of said tooth structure to remove surface, interproximal and gum line foreign deposits therefrom, whereby the hygienic condition of said oral cavity is maintained.

23. The method as in claim 20, wherein said elastic energy waves of said micropulsed stream of liquid is induced therein as said stream is pumped through said applicator.

24. The method as in claim 14, wherein said microstimulating of said gum structure induces a micromassage of the cellular structure thereof.

25. The method of treating the teeth structures, and gum structures, within the oral cavity for hygienic control thereof, with an applicator in the form of a flexible suction cup capable of supporting vibrations in the ultrasonic range and adapted to be inserted within the oral cavity, comprising the steps of:

A. inserting said applicator within the oral cavity,

B. positioning against the structures to be treated the front end of said applicator,

C. generating a stream of liquid within said suction cup to substantially maintain said cup completely filled during engagement with the teeth or gum structures,

D. micropulsing said stream of liquid in said applicator to induce therein energy waves in the ultrasonic frequency range,

E. microstimulating said engaged structure by transmitting said ultrasonically micropulsed energy waves contained in said liquid in said suction cup to effect the treatment thereof,

F. vibrating said suction cup applicator at an ultrasonic rate, and

G. moving said applicator suction cup towards and away from said contacted surface to induce therein a macromassaging effect on said treated structure.

26. The method as in claim 25, and further including the step of pulsing said stream at a frequency below that of said micropulsing frequency to provide doses of mechanical energy at two different frequencies to said treated structure.

27. The method as in claim 25, wherein said applicator has an abrasive surface thereon for engagement with the treated structure.

28. The method as in claim 25, wherein said motion of said liquid is of an amplitude of vibration to produce a cavitational action in said liquid.

29. The method as in claim 25, wherein said liquid is vibrated in the frequency range of 5,000 cycles per second to 1 million cycles per second.

30. Apparatus for removing foreign deposits from teeth, comprising

A. means having an abrasive surface thereon of nonscratching characteristic relative to the teeth and capable of supporting and transmitting ultrasonic vibrations,

B. means for inducing vibrations in said abrasive surface at a frequency in the ultrasonic range,

C. means for maintaining a film of fluid at the cleaning site of said abrasive surface, wherein as said abrasive surface is moved relative to said teeth that it engages, the foreign deposits are removed therefrom and said fluid acts to maintain the cleaning site free of said removed foreign deposits.

31. Apparatus as in claim 30, wherein said fluid is supplied at a temperature and rate to maintain said teeth at substantially a constant temperature during cleaning thereof.

32. Apparatus as in claim 30, wherein said abrasive surface is flexible and adapted to substantially conform to the contour of said teeth.

33. Apparatus as in claim 30, wherein said abrasive surface is in the form of a single pointed member adapted to be selectively positioned against and interproximally of said teeth.

34. Apparatus as in claim 30, wherein said abrasive surface is in the form of a plurality of individual bristle elements each containing an abrasive surface thereon such that the elements assume positions in which they are randomly divided between actual contact with and displacement from the surfaces of said teeth.

35. Apparatus as in claim 30, wherein said motion of said abrasive is of an amplitude of vibration to produce a cavitational action in said fluid film between said abrasive surface and said teeth surfaces when said abrasive surface is displaced therefrom.

36. Apparatus as in claim 30, wherein said abrasive surface is vibrated in the frequency range of 5,000 cycles per second to 1 million cycles per second.

37. Apparatus as in claim 30, wherein said frequency is preferably in the range of 16,000 cycles per second to 40,000 cycles per second.

38. Apparatus as in claim 30, wherein the amplitude of vibration of said abrasive surface is in the range of 0.0001 inch to about 0.070 inch.

39. Apparatus as in claim 30, further including means for providing a stream of fluid for maintaining said film at said cleaning site.

40. Apparatus as in claim 39, and further including means for pulsing said stream of fluid at a preselected pattern of pulses at spaced intervals of time.

41. A system for removing surface, interproximal and gum line foreign deposits from teeth structures, and treating the gum structures, within the oral cavity for hygienic control thereof, comprising

A. applicator means having a pointed tip with a passageway therethrough and an abrasive surface of nonscratching characteristic relative to the teeth that is capable of supporting vibrations in the ultrasonic range and adapted to be inserted interproximally of said teeth within the oral cavity,

B. reservoir means for retaining a supply of liquid,

C. pumping means in communication with said reservoir means for continuously supplying liquid therefrom, said pumping means adapted to form a stream of liquid,

D. instrument means adapted to be hand held by the user and in communication with said pumping means for receiving said stream which is adapted to pass through the instrument passageway extending therethrough,

E. means for removably securing said applicator means to one end of said instrument means with said respective passageways communicating with each other,

F. motor means contained within said instrument means for converting electrical energy into mechanical vibrations at an ultrasonic rate, said motor means in energy transmission relationship to said stream within said instrument passageway to impart thereto micropulsed energy waves for treatment of said structures, with said stream passing through said applicator at said pointed tip for transmitting said energy waves to said treated structures,

G. means for pulsing said stream at a frequency below that of said micropulsing frequency to provide doses of mechanical energy at two different frequencies to said treated structure, and

H. means for coupling said applicator means to said motor means to vibrate said applicator means at ultrasonic rates, whereby said mechanical vibrations of said applicator means is adapted to be transmitted to said treated structures.

42. A system as in claim 41, wherein said pumping means is adapted to pulse said stream within a defined frequency range.