Patent Publication Number: US-6217327-B1

Title: Soft scrub and spray method

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates, generally, to the art of dental hygiene. More particularly, it relates to an apparatus and method for tooth brushing that provides a soft scrubbing action to loosen food particles and plaque and which applies a mist or spray to wash away the food particles at the same time. It also relates to a method for delivering stannous fluoride to tooth surfaces to protect them from acid attack which causes caries. 
     2. Description of the Prior Art 
     It is well known that the mechanical action of toothbrush bristles can loosen food particles and plaque buildup from tooth surfaces and a water spray can wash away the loosened particles. However, it is not easy to scrub all tooth surfaces and apply a water spray at the same time. It would be very useful where braces are worn to have a mechanical scrubbing action and a water spray at the same time. 
     Moreover, it is well-known that fluoride has a beneficial effect on teeth. It reduces the solubility of enamel by protecting the enamel from attack by acids of the type produced by bacteria. Moreover, studies have shown that stannous fluoride has much more efficacy in this regard than sodium fluoride. More particularly, it is about four times as effective as sodium fluoride. 
     Both calcium and phosphate are found in enamel. Stannous fluoride forms links with both of them to prevent their extraction from the tooth by the acid that begins forming about twenty four hours after plaque has begun to form on the surface of a tooth. 
     Although most clinical trials have tested stannous fluoride in ten per cent (10%) concentrations, studies have shown that the decrease in effectiveness is very small even with concentrations as low as 0.4%. 0.2%, and 0.1%. 
     One widely used technique for delivering fluoride to teeth is to add it to local drinking water supplies. Another method is to add it to toothpaste. 
     Neither of these methods is completely satisfactory, because many people live in cities that do not fluoridate their drinking water system, and stannous fluoride is not found in commercially-available toothpaste. 
     Moreover, studies have shown that a topically-applied, water-free 0.4% solution of stannous fluoride is more effective than a toothpaste originally prepared to contain 0.4% stannous fluoride. Studies have also demonstrated that a freshly prepared 0.2% stannous fluoride solution is significantly more effective in protecting a tooth surface than a 50:50 slurry of water and 0.4% stannous fluoride gel, or a slurry of water and a leading brand of toothpaste. 
     Although a dentist can topically apply stannous fluoride to the teeth of patients during an office visit, it is obviously impractical for everyone to visit a dentist twice a day, or even once a day. 
     Thus, there is a need for a consumer-operated device capable of loosening food particles and plaque deposits from all tooth surfaces so that the mechanical action of toothbrush bristles, coupled with a water spray, may remove such deposits before acid formation may begin. There is also a need for a means for topically applying stannous fluoride to tooth surfaces in effective concentrations in the convenience of one&#39;s home. The needed device should not require the user to prepare a gel or a slurry. Instead, the device should be easy to use and compact in size so that it could be stored on a sink or countertop. Its method of use should be self-evident, and it should be constructed of low cost materials so that it is affordable by the average consumer. It should also be useable by people with sensitive teeth and by people with braces. For example, the needed device should be capable of delivering water temperatures of about 110° F. because warm water is not only comfortable for people with sensitive teeth, but it also serves to promote the dissolution of plaque deposits. 
     It is also well-known that many people leave the water running during tooth brushing, thereby wasting large quantities of water. Thus, there is also a need for a tooth-care system that would conserve water. 
     Accordingly, if an apparatus and method could be found that could deliver a mist or spray to tooth surfaces to loosen food particles at the same time mechanical brushing is taking place, that could deliver stannous fluoride in an effective form to protect the teeth from acid attack, that would also conserve water, and that would be useable by people with sensitive teeth, braces, or both, then the art of dental care would be advanced in a substantial way. 
     However, it was not obvious to those of ordinary skill in this art how such an apparatus and method could be provided, in view of the art considered as a whole at the time the present invention was made. 
     SUMMARY OF THE INVENTION 
     The long-standing but heretofore unfulfilled need for an innovation that overcomes the limitations of the prior art is now met by a new, useful, and nonobvious invention including a reservoir means for containing a predetermined volume of a liquid fluid such as water. The novel apparatus includes a toothbrush having bristles and a base to which the bristles are mounted. A plurality of apertures is formed in the base and an outlet conduit means provides fluid communication between the reservoir means and the apertures. An air pump is in fluid communication with an inlet conduit that has a free end positioned within the reservoir means at a preselected location above a liquid level in the reservoir means. It pumps the liquid fluid from the reservoir means to the apertures through the outlet conduit. 
     A bypass conduit provides fluid communication between the inlet conduit and the outlet conduit, bypassing the reservoir. The pump includes a suction inlet that takes in ambient air and a compression outlet in fluid communication with the inlet conduit. Some of the air flows through the bypass conduit and enters into the water flowing through the outlet conduit at a point upstream of the toothbrush so that bubbles are formed in that water. This produces a spray or mist where the water flows out of the toothbrush base through the bristles. 
     A valve is preferably provided in the bypass conduit to regulate the flow of air therethrough. 
     In a second embodiment, stannous fluoride is added to the water in the reservoir. 
     In a third embodiment, a first introducing means introduces a preselected gaseous fluid into the liquid fluid at a preselected location in the inlet conduit. The introducing means includes a remote source of a preselected gaseous fluid under pressure. The remote source is in valved fluid communication with the inlet conduit. 
     In a fourth embodiment, a second introducing means introduces a therapeutic substance such as an antibiotic or the like into the outlet conduit. 
     It is a primary object of this invention to provide a low cost, easy-to-use apparatus for use by individuals in their homes that delivers a spray or mist of water to all tooth surfaces to loosen food particles. 
     Another object is to provide such an apparatus that delivers warm water (approximately 110° F.) to all tooth surfaces. 
     Another major object is to provide an apparatus that allows a soft scrubbing action to remove the loosened food particles from all tooth surfaces at the same time that the water spray is provided. 
     Still another important object is to provide an apparatus and method for delivering stannous fluoride to tooth surfaces in a highly effective form. 
     Another object is to provide an apparatus that delivers stannous fluoride to tooth surfaces in an effervescent liquid medium to enhance the protective effect of the fluoride. 
     Another object is to provide an apparatus that delivers therapeutic substances to the teeth and gums. 
     Still another object is to provide an oral hygiene system that is suitable for use by people with braces or sensitive teeth or both. 
     Yet another object is to provide an apparatus that has beneficial side effects such as the reduction of bad breath, tongue-cleaning, and water conservation. 
     These and other important objects, features, and advantages of the invention will become apparent as this description proceeds. 
     The invention accordingly comprises the features of construction, combination of elements and arrangement of parts that will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawing, in which: 
     FIG. 1 is a schematic diagram of the novel apparatus; and 
     FIG. 2 is an elevational view of a second embodiment of the reservoir that holds water and a stannous fluoride tablet. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the FIG. 1, it will there be seen that an exemplary embodiment of the invention is denoted as a whole by the reference numeral  10 . 
     In its simplest form, tooth-cleaning system  10  includes a pump  12  in fluid communication with inlet conduit  14 , a container  16 , an outlet conduit  18  and a toothbrush  20 . In this configuration, container  16  is a reservoir for a liquid fluid, preferably warm (110° F.) water  22 . Inlet conduit  14  has a free end  14   a  positioned above the level of said liquid  22 , i.e., in non-immersed relation thereto, and outlet conduit  18  has a free end  18   a  immersed within said liquid  22 , as depicted. In this way, ambient air is pumped through inlet conduit  14  by pump  12  into container  16 . 
     A suitable closure means, such as a cork or other air-tight sealing means  24  closes open-mouthed container  16  and has suitable apertures formed therein to receive inlet conduit  14  and outlet conduit  18 . Accordingly, when pump  12  is activated, air pressure within container  16  drives liquid  22  into outlet conduit  18 . The flow rate of liquid  22  is constant and uninterrupted during the tooth cleaning process. 
     Container  16  preferably holds approximately two cups (16 ounces) of solution. It has been found that a good job of teeth-cleaning can be accomplished with about 10-12 fluid ounces of water. The novel apparatus dispenses that amount of water in about two minutes, which allows plenty of time for thorough tooth brushing. 
     Toothbrush  20  has a hollow handle  26  with inner passageway  28  formed therein. The proximal end  28   a  of inner passageway  28  is in fluid communication with distal end  18   b  of outlet conduit  18  by means of any suitable connector means. The distal end  28   b  of inner passageway  28  is in fluid communication with bristle base  30  which is suitably apertured to allow liquid  22  to flow between bristles  32  substantially as depicted. In an unillustrated alternative form of the novel apparatus, outlet conduit  18  bypasses handle  26  and is connected directly to bristle base  30 . 
     Pump  12  is preferably a six volt pump and may be battery operated by four AA batteries  13 . Alternatively, it may be powered by conventional household current that is rectified and stepped down to six volts. It produces a constant volumetric flow of about one liter per minute so that the liquid flow from reservoir  16  is steady. 
     For users with sensitive teeth, liquid  22  is preferably warm tap water (110° F.). Bristles  32  must contact the tooth surfaces to physically remove the loosened food particles, but the brushing action can be quite soft. 
     Significantly, the first embodiment includes bypass conduit  40  that interconnects inlet conduit  14  and outlet conduit  18  at a preselected location. The opposite ends of bypass conduit  40  are positioned in fluid communication with inlet and outlet conduits  14  and  18 , respectively, by “T”-shaped fittings  39 ,  41 . Bypass conduit  40  provides fluid communication between inlet conduit  14  and outlet conduit  18  so that air or other gaseous fluid may bypass reservoir  16  and become entrained in the liquid flowing toward toothbrush  20  through outlet conduit  18  as indicated by bubbles  42 . This effervescence is beneficial because it produces a gas/liquid discharge at bristles  32 , enhancing the cleaning action of the fluoridated water. The effervescence also slows down the rate of water flowing out of container  16  so that it is not emptied too quickly. 
     Control valve  44  may be positioned in bypass conduit  40  to control the flow rate of gaseous fluid therethrough. If control valve  44  is closed, no bubbles will appear in outlet conduit  18  and the solution in reservoir  16  will be emptied quite quickly, i.e., in less than a minute when said reservoir  16  is holding about 10-12 ounces of solution. This may not allow the user sufficient time to thoroughly apply the solution to all tooth surfaces. If control valve  44  is opened all the way, the gas pressure may be too high and the amount of effervescence may be so high as to slow down the emptying of reservoir  16  too much. It has been found that the amount of effervescence is about right when control valve  44  is about half open. This allows the user about two minutes to perform the tooth brushing procedure. 
     In a second embodiment, a tablet  34  of stannous fluoride or equivalent is dissolved in liquid  22  prior to use of novel apparatus  10 . Accordingly, the structure just described delivers dissolved stannous fluoride to the teeth of a user. Significantly, the dissolved stannous fluoride is in a highly effective form and is capable of protecting the teeth against acid attack. Accordingly, if the novel apparatus is used after every meal, the bristles will loosen the food particles and plaque deposits, the water will wash away the loosened food particles and plaque deposits, and the stannous fluoride will protect the enamel. Twice daily use, about every twelve hours, will also be highly effective in cleaning the teeth and in reducing enamel solubility. 
     In a third embodiment of the invention, a gaseous fluid such as carbon dioxide, oxygen, nitrogen, or mixtures thereof, for example, is entrained into inlet conduit  14  to enhance the operation of the apparatus. For example, oxygen delivery may be beneficial for a patient who has undergone a tooth extraction or other surgical procedure. A first introducing means includes flow control valve  36 , positioned in a conduit confluent with the base of a “T”-connector  37 , and provides adjustable fluid communication between a source  38  of gaseous fluid under pressure and inlet conduit  14 . The preferred flow rate is about one liter per minute. 
     In a fourth embodiment, a second introducing means includes another control valve  46 , positioned in a conduit confluent with the base of “T” connector  47 , controls the flow rate of a preselected medication into outlet conduit  18 . Specifically, connector  47  provides fluid communication between a source  49  of medication under pressure and outlet conduit  18 . The medication may be an antibiotic or other therapeutic agent having utility in the care of the teeth and gums. 
     Control valve  50  in outlet conduit  18  provides additional control. 
     FIG. 2 depicts an alternative structure for reservoir  16 . A funnel  60  having a downspout  62  is disposed within said reservoir in upstanding relation to bottom wall  64  of reservoir  16 . Stannous fluoride tablet  34  is positioned within downspout  62 . Perforations  66  are formed in downspout  62 . Outlet conduit  18  is in fluid communication with the lowermost end of downspout  62 . In this way, tablet  34  is dissolved uniformly and the dissolved medication is promptly carried away by outlet conduit  18 . Tablet  34  may have multiple layers. For example, it could have an outer layer of baking soda and its interior could include stannous fluoride. An innermost layer could include a breath freshener so that the user feels refreshed when the cleaning has been completed. 
     The novel apparatus has numerous advantages. The warm spray of water loosens food particles and helps to dissolve plaque and eases their subsequent removal by brushing. The stannous fluoride dissolved therein reduces the enamel solubility of the cleaned teeth in a highly efficient manner. The apparatus and method effectively clean teeth fitted with braces and provides a comfortable cleaning for those having sensitive teeth. The tongue can also be cleaned, reducing halitosis. Moreover, the novel apparatus requires less water than conventional tooth brushing. 
     The novel apparatus delivers free stannous fluoride ions to the teeth and gums. These ions are easy to absorb and are not found in conventional toothpastes. Free stannous fluoride ions are also available to fight infection. 
     This invention represents a major breakthrough in the art of dental care. Being drawn to a pioneering invention, the claims that follow are entitled, as a matter of law, to broad interpretation to protect the heart or essence of the invention from piracy. 
     It will thus be seen that the objects set forth above, and those made apparent from the foregoing description, are efficiently attained. Since certain changes may be made in the foregoing construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing construction or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention that, as a matter of language, might be said to fall therebetween. 
     Now that the invention has been described,