US3924335A

US3924335A - Ultrasonic dental and other instrument means and methods

Info

Publication number: US3924335A
Application number: US209971A
Authority: US
Inventors: Lewis Balamuth; Arthur Kuris; Manuel Karatjas
Original assignee: Ultrasonic Systems Inc
Current assignee: Ultrasonic Systems Inc
Priority date: 1971-02-26
Filing date: 1971-12-20
Publication date: 1975-12-09
Anticipated expiration: 1992-12-09
Also published as: GB1384421A; IT948354B; CA959679A; FR2127816A5; DE2208764A1

Abstract

The invention discloses various ultrasonic dental equipment primarily adapted to be used for professional dental purposes as well as various dental procedures capable of being performed with the ultrasonic instrumentation. The ultrasonic dental system permits the user to selectively utilize a variety of fluids within the oral hygenic procedures carried out by the dentist. The fluids may be selective medicaments that are pumped through the dental system from either an external source i.e., water, to various other fluids each for its intended usage. The invention discloses motor-convertor systems in which a single piezoelectric crystal element is used to both simultaneously drive an ultrasonic motor and provide a feedback signal for frequency sensing means to permit the convertor to adjust itself thereto.

Description

AU 335 EX United States Patent on 3,924,335 Balamuth et al. 1 Dec. 9, 1975 [54] ULTRASONIC DENTAL AND OTHER 3.7mm 11/197: Robinson 32/DIG. 4 INSTRUMENT MEANS AND METHODS 3.809.977 5/1974 Balamuth et al 32/58 X inventors: Lewis Balamuth, New York; Arthur Kuris, Riverdale; Manuel Karatjas, Glen Oaks, all of N.Y.

Ultrasonic Systems, Inc., Farmingdalc, N.Y.

Filed: Dec. 20, 1971 Appl. No.: 209,971

Related US. Application Data Continuation-impart of Ser. No. ll9,298, Feb. 26, 197i, Pat. No. 3,809,977.

Assignee:

US. Cl. 32/58; 32/DlG. 4; 128/24 A; 3l0/8.l

Int. CL... A61C 3/06; A61H l/OO; HOlV 7/00 Field of Search 32/26, 27, DlG. 4, 58; l28/24 A; 3l0/8.l, 26

References Cited UNITED STAllzS PATENTS lO/l965 Balamuth et al 32/DlG. 4

Primary livuminer-Robert Peshock Assistant Examiner-J. Q. Lever [57] ABSTRACT The invention discloses various ultrasonic dental equipment primarily adapted to be used for professional dental purposes as well as various dental procedures capable of being performed with the ultrasonic instrumentation. The ultrasonic dental system permits the user to selectively utilize a variety of fluids within the oral hygenic procedures carried out by the dentist, The fluids may be selective medicaments that are pumped through the dental system from either an ex- I ternal source i.e., water, to various other fluids each for its intended usage.

The invention discloses motor-converter systems in which a single piezoelectric crystal element is used to both simultaneously drive an ultrasonic motor and provide a feedback signal for frequency sensing means to permit the convertor to adjust itself thereto.

31 Claims, 32 Drawing Figures U.S. Patent Dec.91975 Sheet1of16 3,924,335

FIG. I

US. Patent Dec.91975 Sheet2of 16 3,924,335

U.S. Patent Dec.91975 Sheet30f16 3,924,335

U.S. Patent 1960.91975, Sheet40f16 3,924,335

US. Patent Dec.91975 Sheet5ofl6 3,924,335

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US. Patent Dec.91975 Sheet6of 16 3,924,335

m Qm

US. Patent Dec.91975 Sheet7ofl6 3,924,335

U.S. Patent Dec.91975 Sheet110f16 3,924,335

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US. Patent Dep.91975 Sheet 12 of 16 3,924,335

umw 125:6

hww N3 RQN U.S. Patent Dec.9l975 SHeet 13 of 16 3,924,335

US. Patent Dec.91975 Sheet 14 of 16 3,924,335

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a xv Q5 E 30E T US. Patent Dec.91975 Sheet 15 of 16 3,924,335

ULTRASONIC DENTAL AND OTHER INSTRUMENT MEANS AND METHODS CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of our copending application Ser. No. 119,298 filed Feb. 26, 1971 now U.S. Pat. No. 3,809,977 issued May 7, 1974, entitled ULTRASONIC KITS AND MOTOR SYS- TEMS, which entire subject matter of the copending application is incorporated herein by reference as if fully herein set forth.

BACKGROUND OF THE INVENTION The present invention relates to an ultrasonic unit adapted to be used primarily for professional dental applications to perform a variety of functions and procedures as well as the system designed therefore.

Heretofore, the use of ultrasonic energy in dentistry for professional purposes has been limited to the use of water as the fluid utilized within dental prophylaxis procedures in order to remove foreign substances from within the oral cavity and perform other dental proce dures. The present inventors have now discovered that a host of dental procedures not heretofore available may be realized by a system that permits dentists to select fluids having various chemical formulations such that both physical and psychological benefical results are obtained.

Accordingly, by the provision of interchangeable and replaceable fluid supply sources that can be directed through the ultrasonic dental handpiece, the scope and variety of dental techniques are increased to a considerable extent. It might be stated that this additional flexibility given to the dentist permits a number of dental procedures to be carried out that were heretofore not practicable.

By way of background, the use of Kilohertz ultrasonic energy in the dentists office has become commonplace, chiefly due to the pioneering work of the inventors of the present invention. For example, a dental operative unit is currently widely used by dentists for a great variety of procedures including:

1. Drilling of teeth 2. Periodental gingival-tooth care Mesztcazaithszraey 4. Amalgam Packing 5. Orthodontic aids in shaping teeth and in removing dental cements from braces 6. Surgical procedures related to gingivectomy and endodontic procedures 7. Gingival massage and tooth cleaning Now, the inventors, having been involved in the historical growth of these techniques and procedures, have carefully followed and evaluated the changing requirements which improved ultrasonic dental equipment should embody. In this patent, such novel improved equipment and new techniques will be disclosed in their appropriate places.

In the first place, advances in the electronic art combined with advances in the technology of transducer materials, now permit the use of simplified solid state circuitry and more efficient transducer materials, so that better generators and handpieces are possible. In the case of transducer materials, both ferromagnetic and ferroelectric ceramics have reached a quality resulting in high conversion efficiency, high and low temperature stability, and a long, relatively non-aging 2 product life. These factors are partially reflected in one of the inventors US. Pat. No. 3,547,l 10. in the field of dentistry.

Now, at the same time, the inventors have been involved as a part of a rapidly expanding aspect of the ultrasonic art in the biological, chemical and medical fields. It is the intention of this disclosure to show how the technological ultrasonic motor-converter advances. outlined above, may be combined with the uses of ultrasonic effects in the bio-medical areas to produce a unique novel professional dental instrumentation to carry out a wide variety of procedures. Two of the present inventors have already pioneered in the development of ultrasonic instrumentation, which has resulted in world-wide acceptance of most of the procedures outlined above.

One of the most important novel features of the present dental instrumentation is the provision of readily interchangeable reservoirs of fluid medicaments for specialized professional dental uses. For, example, thepresent unit employs a twoway hydraulic system, which permits the use of either a regular ordinarly available outside water supply, or an internal hydraulic system, utilizing a fluid supply tank which is removably attachable to the professional dental unit itself.

Now, when the internal hydraulic system is intended for use by the dentist (or oral hygienist), the operator merely sets the appropriate control and attaches a ster ile plug-in source of desired medicament fluid into the place provided in the equipment. All this is of course described in detail as the disclosure proceeds. In order to understand better the problems which must be solved to allow this novel procedure, one example will be given. U

The removal of calculjs from gingival and subgingival hard tooth surfaces (dentin and enamel) is one of the chief problems facing the periodontist in treating the undesireable conditions found in the mouth, and is essential for maintaining and restoring good dental health. A chemical solution is often used which selectively stains plaque and calculus and thereby assists the dentist in determining the thoroughness of a given prophylactic oral treatment. Such a solution is called a disclosing solution. In the applicants subject dental unit, one of the self contained medicament fluid containers may contain such a disclosing solution and may be conviently stored away from the unit until it is desired by the dentist for use. Now, if he has used such a procedure, the internal hydraulic system of the unit will have its various tubes and conduits filled with said disclosing solution. If the dentist wishes for example to use plain water, or a different medicament solution for his next patient, or even for the same patient, it is essential to be able to clean out the internal hydraulic system completely so that is is replaced with clear, clean water. As will be disclosed completely in due course, the present invention provides precisely the means needed to accomplish this purpose, and as will be appreciated this is another novel aspect of the present invention.

Additionally, the present invention prefers to use piezoelectric ceramic transducers, because of the high efficiency and great ease in fabrication of motors made with such materials, although magnetostrictive transducers may also be used.

Also, theinventors have been aware of the need to provide quick change operating hand instruments as compared to certain prior art inventions of providing magnetostrictive laminated stack inserts, which tele- 3 scope into a handpiece which comprised a coil winding and a thin insulation jacket. Although quite safe, the thin insulator plastic jacket nevertheless required the operator to grasp the jacket in the area where the coil was wound.

In the present invention the concept of removably detachable insert is not necessarily relied on and in its place there has been substituted a removably detachable handpiece. The handpiece merely unplugs and replugs into a small receptacle terminating into the cable, which connects said receptacle and the output means of the converter system.

This simple, yet novel, transformation of the converter ultrasonic motor connector means introduces another new dimension into the instant invention. This is because the excitation of the motor does not depend upon a fixed coil, which in turn, must always engage a seperate insert properly in order for the dental instrument to function as designed For example whereas the magnetostrictive insert type of motor is restricted to the driving coil in the handpiece means, the detachable motor of the present invention may be changed to any type of piezoelectric or magnetostrictive self contained motor designed to operate at the impedance level of the converter output. And in fact, the converter output may be readily provided with a tapped output means, whereby a number of different impedances may be available for use. Thus, the output design of the present invention provides a versatility not found in the prior art.

MOTOR-CONVERTOR SYSTEM The present invention also relates to an ultrasonic motor-converter system in which the piezoelectric crystal is used for both driving the motor and producing a feed-back signal.

Heretofore, the ultrasonic motor art has developed in that piezoelectric element or crystals have been utilized for powering the ultrasonic motor and exciting the motor at a desired frequency range. In the above referenced co-pending patent application there is disclosed the utilization of a driving crystal or crystals for powering the ultrasonic motor and a feed-back or third crystal element adapted to be used for the purpose of providing a signal feed-back which is transmitted to the convertor and which signal is utilized by the convertor to adjust the frequency of the convertor system in respect thereto.

Although, motors of the aforementioned design in the co-pending application produce the requisite capacity of withstanding the necessary work-loads, it has been found that the utilization of two or three crystals require a number of related machined component parts that have to be assembled in proper relationship to each other, each one adding to the cost of the completed motor. Furthermore, a major portion of this cost being the crystal material itself. Accordingly, in order to obtain an economical motor, i.e., one adaptable for home-consumer and other use, it has been considered that it would be advantageous if the benefical effects of an ultrasonic motor could be produced in which the driving and sensing were incorporated in a single crystal so that the number of component parts would be substantially reduced. This novel design of an ultrasonic motor incorporating a single crystal element is herein disclosed.

OBJECTS OF THE INVENTION The object of the invention is to provide new and improved dental procedures utilizing ultrasonic energy.

Another object of the invention is to provide new and novel dental procedures having both physical and pyschological effects on the patient.

Another object of the present invention is a new and novel dental system permitting the selective utilization of medicaments within the cleaning procedure.

Another object of the invention is to provide a novel motor-convertor system in which a single piezolectric element may be utilized for both driving the motor and generating a feed-back signal to the convertor.

. Another object of the present invention is to provide individual containers for the supplying of the medicaments for use in conjunction with the dental system.

Other objectives of the invention will be apparent as description proceeds.

SUMMARY OF THE INVENTION The present invention provides for a series of novel interrelated steps in combination with each other to obtain dental procedures not heretofore obtainable with the prior art.

In accordance with one aspect of the present invention a system is provided that permits the dentist, or other user, for the first time to be able to select a source of fluid in a dental procedure from a closed system or from conventional water supply. The ability to permit a dentist to operate at will from either a closed system or open system permits the dentist to utilize a series of medicaments that may be provided in sealed containers and plugged into the dental system for performing various applications.

The apparatus in accordance in one aspect of the invention, includes a motor-convertor system in which the motor contains a piezoelectric material which is formed as to provide longitudinal ultrasonic vibrations when it is activated by high-frequency electrical impulses and the resultant ultrasonic vibrations are transmitted through the motor to the point of use. A portion of the crystal is isolated and electrically converted such that a feed-back signal is generated therein and in turn the electrical signal is transmitted to the convertor in order to properly adjust itself to the frequency at which the motor is vibrating.

In accordance with one aspect of the invention the crystal utilized is of tubular configuration. The crystal is so fonned as to provide longitudinal ultrasonic vibrations when it is activated by high-frequency electrical impulses and the resultant ultrasonic vibrations are transmitted by the tip to the point of use. The crystal utilized is of tubular configuration made preferrably of lead zirconate and/or leadtitanate ceramic material which is so formed that it has the quality of expanding and contracting longitudinally at ultrasonic frequencies and is joined end to end to the tip by an epoxy cement or other means so that the ultrasonic tip movements are directly related to the longitudinal expansion and contraction of the activated crystal. While the later may be designed to operate at frequencies from 25,000 c.p.s. to 45,000 c.p.s., for dental applications such frequencies usually will not exceed this frequency, the crystal and attached tip constitute a matched pair and form said component resonator. Provision is made in the handpiece for supporting and retaining the crystal and tip. In addition, a water duct in conjunction with the handpiece and tip is provided for a stream of water from the tip during use.

In accordance with another aspect of the invention a series of novel receptacles are disclosed which are prefilled on a commercial basis and acquired by the dentist for use in conjunction with apparatus defined herein. The receptacles are designed such that they may be simultaneously vented and may have a valve mounted thereon which valve meets with an accompanying valve seat on the unit such that the fluid contained in the closed reservoir or container may be pumped through the system and used by the dentist.

In accordance with another aspect of the invention a flushing procedure is provided such that the user may cleanse the complete dental system with water when switching from one type of medicament to another. This aspect of the invention is unique to the provision of a system in which a variety of different fluids may be introduced, some of which may not be compatable with each other, or just merely the fact that the next patient should not be subjected to the fluid of the previous patient. Thus, the system has a built-in flushing cycle to permit the necessary flushing thereof.

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 view and in which:

FIG. 1, is a perspective view of an ultrasonic dental system in use;

FIG. 2, is a front elevational view of ultrasonic instrument means for use in the present invention;

FIG. 3, is a side elevational view partially in crosssection of the instrument means of the present invention;

FIG. 4, is an enlarged sectional view of the reservoir relationship;

FIG. 5, is a side elevational view of ultrasonic instrument means for use in the present invention;

FIG. 5A, is a side elevational view in cross-section of the instrument means in assembled relationship taken along a medial plane;

FIG. 5B, is a view in cross-section taken along the plane indicated by the line 58 5B in FIG. 5A;

FIG. 5C, is a view in cross-section taken along the plane indicated by the line 5C SC in FIG. 5A;

- FIG. 5D, is an enlarged view in cross-section of the assembled end of the crystal;

FIGS. 6 6D are similar to FIGS. 5 5D and illustrate another embodiment of the invention;

FIGS. 7 and 8 are enlarged partial views illustrating another form of sensing means in accordance with the present invention;

FIG. 9, is a side elevational view in cross-section of a novel container;

FIGS. 9A and 9B, are enlarged views in cross-section illustrating other forms for sealing the container;

FIG. 10, is a view illustrating the assembled relation of the container and instrument means;

FIG. 11, is a diagrammatic view illustrating the relative components;

FIGS. 12 16, are schematic more or less diagrammatic views of the hydraulic system of the invention during its various stages of operation:

FIG. 17, is a view similar to FIG. 12 illustrating the use of two or more receptacles;

FIG. 18, is a view similar to FIG, 13 illustrating another hydraulic electrical system;

FIGS. 19 and 20, are a front and side elevational views, respectively partly in section, of the dental system containing a plurality of reservoir; and

FIGS. 21 and 22, illustrate various electrical schematics of converters that can be used to drive the various ultrasonic motors described herein.

PREFERRED EMBODIMENTS OF THE INVENTION Turning now to the drawings FIGS. 14 have disclosed an ultrasonic system generally indicated by reference numeral 10 for use by an individual 11, that may be a dentist or other trained person, using the equipment 10 on a patient 12 seated on a chair 13, as for example a dentist using the equipment for dental prophylaxis purposes. The equipment is seen to include a cabinet 14 on a table or other support 16, which contains therein an ultrasonic converter 15, as well as a tray or reservoir 20 on the top 18, and containing a supply of a fluid 22, which in conventional manner, is pumped from a reservoir 20, by a pumping means 25 (see FIG.

4) contained within the cabinet 14.

Ultrasonic instrumentation means 26 is coupled to the converter means 15 and the pumping means 25 by a cable means 28 which contains a current supply line 59 and a fluid conduit 167. The ultrasonic equipment includes an accessory implement means 30 that may have various shapes and configurations, and adapted to be removably secured to the adapter or the coupling means 35.

The cabinet 14 contains power-control means in the form of a switch 36 having ON and OFF positions and a variable switch 38 to regulate the power of the converter 15. An indicator light 40 is provided on the front panel 32 of the cabinet 14 to indicate when the switch 36 is in its ON position. A fluid selector switch 42 is provided on the front panel 32 and provides a selection of either the internal fluid supply or the external supply such that, as herein described, the user has the flexibility of using the instrumentation 10, from an external water supply or an internal fluid supply which permits him to use a host of liquids to perform a number of dental procedures. The fluid regulator means 41 includes a fluid regulator 45 that contains a dial 46 to vary the rate of the pumping means 25 when the fluid selector switch 42 is on its internal position, and which pumps the fluid from the reservoir 20 through the cable 28 in a manner which is well known in the art. When the fluid selector switch 42 is in the external position, then the fluid regulator switch 45 acts to control the liquid flow from the external fluid supply so that the amount of fluid being transmitted through the instrumentation means 26 is controlled as well as the degree of vibrations of the tip thereof by the proper control of the various related switches of the front panel 32 on the cabinet 14.

The cabinet 14 is seen to include support means 50, which may extend from the side wall 52 thereof in the form of an arm 54 supporting a bracket 55 having a recess or seat 56 extending on an angle therewith such that the assemblied accessory means 30 and adapter

Claims

1. An ultrasonic dental system including A. a converter for providing electrical current at an ultrasonic rate, B. an accessory having a tip for use in the oral cavity when ultrasonically vibrated, said accessory including 1. housing means, 2. a transmission member having a rear section and a front section, said front section extending beyond said housing and having said tip secured thereto, 3. transducer means connected to said section for driving said transmission member, and 4. means to suply a fluid to said tip, C. means electrically connecting said converter to said transducer means in said accessory, D. fluid regulating means communicating with said accessory means to supply a fluid to said tip, E. internal fluid supply means including dispensing means adapted to be coupled with a liquid reservoir communicating with said fluid regulating means to provide an internal supply of liquid to the accessory, F. external fluid supply means communicating with said fluid regulating means to provide an external supply of liquid to the accessory, G. control means communicating with said fluid regulating means for permitting selection of fluid from said internal fluid supply means or said external fluid supply means, H. liquid reservoir means adapted to be readily engaged with said dispensing means to permit the utilization of a variety of fluids within the oral hygienic procedures to be conducted with the dental system, and I. means for flushing said internal supply means with fluid from said external supply means.

2. a transmission member having a rear section and a front section, said front section extending beyond said housing and having said tip secured thereto,

2. An ultrasonic system as defined in claim 1, and further including means for flushing the dental system from said regulating means through said accessory.

2. pumping the fluid through said instrument, and

2. housing means enclosing said motor, and

3. electrical connecting means associated with said housing means and connected to said motor, said housing means adapted to be releasably connected to said adapter for the transmission of electrical energy to said motor when in its assembled position, and I. fluid regulating means communicating with said liquid reservoir means and accessory means to supply the fluid in said reservoir to said tip at a selected rate.

3. An ultrasonic system as defined in claim 1, and further including: a. an adapter coupled to said converter for transmission of said electrical energy, b. a cabinet housing said converter c. support means for holding said adapter in fixed position relative to said cabinet when not in use, and d. a plurality of accessories each adapted to be interchangeable with and releasabley connected to said adapter.

3. transducer means connected to said section for driving said transmission member, and

3. regulating the rate of pumping of said fluid through the instrument, and C. simultaneously transmitting to the selected structure mechanical vibratory energy in the ultrasonic frequency range by means of said tip directly placed in energy transmission relationship to said structure, whereby said fluid has a beneficial effect on the patient as said treatment is obtained by transmitting ultrasonic energy to the treated structure through substantial direct engagement of said tip and through the liquid medium of said stream.

4. means to suply a fluid to said tip, C. means electrically connecting said converter to said transducer means in said accessory, D. fluid regulating means communicating with said accessory means to supply a fluid to said tip, E. internal fluid supply means including dispensing means adapted to be coupled with a liquid reservoir communicating with said fluid regulating means to provide an internal supply of liquid to the accessory, F. external fluid supply means communicating with said fluid regulating means to provide an external supply of liquid to the accessory, G. control means communicating with said fluid regulating means for permitting selection of fluid from said internal fluid supply means or said external fluid supply means, H. liquid reservoir means adapted to be readily engaged with said dispensing means to permit the utilization of a variety of fluids within the oral hygienic procedures to be conducted with the dental system, and I. means for flushing said internal supply means with fluid from said external supply means.

4. An ultrasonic system as defined in claim 1, and wherein said transducer means includes a portion thereof for driving said member and an electrically insolated protion thereof for sensing variations in frequency of said motor and regulating the alternating field of said converter to the corresponding frequency.

5. An ultrasonic system as defined in claim 1, and further including pumping means communicating with said internal fluid supply means for pumping fluid from said reservoir to said fluid regulating means.

6. An ultrasonic system as defined in claim 1, wherein said fluid is supplied through said tip.

7. An ultrasonic system as defined in claim 1, wherein said fluid is supplied adjacent said tip.

8. An ultrasonic system as defined in claim 1, and further including hydraulic system means including: a. a first valve having input and output ports, said input port adapted to be connected to said external source of fluid supply, b. a second valve having input and output ports, c. conduit member having two input ports and an output port, one of said input ports being coupled to said output port of said first valve, the other of said input ports being coupled to said output port of said second valve, said outptut port being coupled to said means to supply a fluid to said tip through said fluid regulating means, and d. a fluid pump having a fluid chamber therein with an input and output port, said output port being coupled to said second valve input port, said pump being adapted to be operator activated, and forming part of said internal fluid supply means and coupled to said reservoir.

9. An ultrasonic system as defined in claim 8, and further including operator activated control and selector switch means coupled to said control valves and said pumping means for providing external fluid operation, internal fluid operation, flushing operation, and priming operation.

10. An ultrasonic dental system including A. a cabinet, B. a converter for providing electrical current at an ultrasonic rate contained within said cabinet, C. an adapter coupled to said converter for transmission of said electrical energy, D. support means for holding said adapter in fixed position relative to said cabinet when not in use, E. a plurality of accessories each adapted to be interchangeable with and releasably connected to said adapter and having a dental tip at one end thereof, F. dispensing means for retaining a reservior in fixed position relative to said cabinet when the dental system is in use, and G. removable liquid reservoir means adapted to be readily engaged with said dispensing means in associated relationship with said cabinet and communicating with said adapter to provide an internal supply of liquid to the accessory, H. said accessories each including:

11. An ultrasonic system as defined in claim 10, wherein said dental tip is adapted to be removably secured to said accessory for transmission of the ultrasonic mechanical vibrations.

12. An ultrasonic system as defined in claim 10, and further including: a. external fluid supply means communicating with said fluid regulating means to provide an external supply of liquid to the accessory, and b. control means communicating with said fluid regulating means for permitting selection of fluid from said internal reservoir means or said external fluid supply.

13. An ultrasonic system as defined in claim 12, and further including means for flushing said internal fluid supply means with fluid from said external fluid supply means.

14. An ultrasonic system as defined in claim 12, and further including means for flushing the dental fluid from said external Fluid supply means.

15. The method of treating the gingival and tooth structures of the oral cavity for hygienic control thereof, with an ultrasonic dental instrument having a tip adapted to be inserted within the oral cavity, comprising the steps of: A. inserting said tip within the oral cavity, B. supplying to said tip a stream of medicinal fluid for treatment of the gingival or tooth structures from an internal fluid supply that permits the selection and control of said fluid, and wherein said step of supplying to said tip a medicinal fluid includes:

16. The method as defined in claim 15, and further including the step of flushing said area treated with said medicinal fluid with another fluid.

17. The method as defined in claim 15, wherein said medicinal fluid is an analgesic.

18. The method as defined in claim 15, wherein said medicinal fluid is fluoride.

19. The method as defined in claim 15, wherein said treatment is conducted subgingivly.

20. The method as defined in claim 15, wherein said fluid is of a red color.

21. The method as defined in claim 15, wherein said fluid is provided through said tip.

22. The method as defined in claim 15, wherein said fluid is provided adjacent said tip.

23. The method as defined in claim 15, wherein said medicinal fluid is a plaque dye.

24. The method as defined in claim 15, wherein said medicinal fluid is an anti plaque solution.

25. The method as defined in claim 15, and further including the step of controlling the amplitude of vibration of the dental tip by regulating the electrical power delivered thereto.

26. The method as defined in claim 15, and further including flushing the dental instrument with fluid from the external source after completing the treatment.

27. The method of treating the gingival and tooth structures of the oral cavity for hygienic control thereof, with an ultrasonic dental instrument having a tip adapted to be inserted within the oral cavity, and capable of supplying fluid from either an external source, or an internal source which is selectable by the user of the instrument, A. providing an internal source of fluid in a plurality of independent reservoirs, B. selecting a medicinal fluid to be applied in said oral cavity from one of said reservoirs, C. coupling the selected reservoir to the dental instrument, D. inserting said tip within the oral cavity, E. pumping the fluid for supplying to said tip said fluid for treatment of the gingival or tooth structures from said internal fluid supply, and F. simultaneously transmitting to the selected structure mechanical vibratory energy in the ultrasonic frequency range by means of said tip directly placed in energy transmission relationship to said structure, whereby said fluid has a beneficial effect on the patient as said treatment is obtained by transmitting ultrasonic energy to the treated structure through substantial direct engagement of said tip and through the liquid medium of said stream.

28. The method as defined in claim 27, and further including the step of regulating the rate of pumping of said fluid through the instrument.

29. The method as defined in claim 27, and further including the step of controlling the amplitide of vibration of the deNtal tip by regulating the electrical power delivered thereto.

30. The method as defined in claim 27, and further including flushing the dental instrument with fluid from the external source after completing the treatment.

31. The method as described in claim 27, and further including the step of flushing said areas treated with said medicinial fluid with another fluid.