Note: This text would have been used in a patent application, but the Patent and Trademark Office has let us down.  Lobbyists and Congress weakened patent protections with the America Invents Act, and patent trolls from big business simply litigate with individual inventors until they get what they want.1. At this writing, the PTO averages 16.1 months before it takes the first action on a patent application, and 25.7 months to process the average application. Over 500,000 patent applications are now awaiting examination2

 

Field of the Invention

The present invention pertains to dental tools for use on grazing animals such as horses, and more particularly pertains to powered equine dental apparatus for floating (grinding) the teeth of horses to remove over length tooth crowns and sharp edges.

Background

Most grazing animals have molars which continuously erupt over the course of their lives. This continued growth generally offsets the wear on the enamel that comes from grazing. But teeth wear unevenly, and in time irregularities develop. These irregularities – spikes and sharp projecting edges – can injure the tongue and cheek of the grazing animal. If untreated, the animal may eat less because of the discomfort, and lose weight.

Horses constitute the largest group of grazing animals that receive dental assistance from veterinarians. A vet may need to grind or rasp off the developing irregularities – a process called floating, rasping, or filing – two or three times a year. Unlike most other domesticated grazing animals, today’s horses live much longer than they did even 100 years ago, and their dependence on grazing makes them dependent on aging teeth.

Traditionally, vets and equine dentists use a manual tooth file to float teeth in horses. This device consists of a rasp at the end of a long rod. In use, the vet sedates the horse, holds the mouth open (sometimes using an equine dental halter), reaches in with the tool, and files with an in-and-out motion. A series of files, from coarse to fine, are used to smooth the irregularities. Files are usually placed in a bucket of water after use, to cool.

Unfortunately, almost everything is wrong with this approach:

  • It is very difficult to see exactly what is happening with the files, so vets have to measure their progress by listening to the sound that the file makes against the molars;
  • The brisk action causes the file and teeth to heat up, jeopardizing the health of the enamel;
  • It is easy to catch the horse’s tongue or cheek with the file, immediately causing tissue damage;
  • The effort is time-consuming.
  • The effort is exhausting.

Some power floats have appeared on the market, but have not offered much improvement on manual methods:

  • It is no easier to see what is happening with the floating operation;
  • The action of the file is even brisker than with manual filing, causing both file and teeth to heat even more;
  • It is still easy to damage soft tissue in the mouth;
  • The effort is still exhausting. Instead of tiring from stroking with the lightweight file, fatigue comes from holding a heavy tool in an awkward position.

Patents for devices for floating a horses teeth are well known in the prior art. They range from hand-held manual floats and files to power floating devices having rotating or reciprocating grinding bits or pads.

Powered devices in prior art include the devices disclosed in:

  • Foot pedal, reciprocating float: U.S. Pat. No. 741,519 which issued Oct 13, 1903 to Mahaffy. This patent employed a foot pedal to power a flexible shaft which through a rotary cam powered a reciprocating float.
  • Motor, reciprocating float: U.S. Pat. No. 889,462 which issued on Jun 2, 1908 to Helm. This patent used a motor to power a reciprocating blade.
  • Reciprocating saw attachment: U.S. Pat. No. 5,851,111 which issued on Dec. 22, 1998 to Long et al. This patent provides an adapter that can attach an equine dental float to a reciprocating saw. The saw may be powered by betteries, wall current, or compressed air.
  • Compressed air, reciprocating float: U.S. Pat. No. 5,888,064 which issued on Mar. 30, 1999 to Stubbs. This patent includes an air-powered reciprocating rasp that may be connected to a compressor. Waste air is directed out an exit hose.
  • Battery powered motor, circular float: U.S. Pat. No. 6,273,712 which issued on Aug. 14, 2001 to Rach and Herron. This patent includes a variable speed motor powered by a rechargeable battery, a clutch, and a water reservoir and squeeze bulb that can be used to squirt water onto the area being worked. It does not contain a brake, and offers circular rather than reciprocal motion.

 

Beyond how such a device would be powered, there are patents pertaining to desirable features:

  • U.S. Pat. No. 854,855 which issued May 28, 1907 to Martin. This patent included provision to protect the lips and gums from laceration.
  • U.S. Pat. No. 2,442,033 which issued on May 25, 1948 to Bowers and Brantly. This patent delivered water or other liquid to a grinding bit that moved in a circular motion.
  • U.S. Pat. No. 4,722,685 which issued on Feb. 2, 1988 to de Estrada. This patent partially shields a grinding bit extending from a hollow tube. Water may be ejected through the tube, and the partial shield protects tongue and cheeks.
  • U.S. Pat. No. 7,172,415 which issues on Feb 6, 2007 to Harvey and Henry and its continuation, U.S. Pat. No. 8,152,516 which issues on Apr 10, 2012 to Harvey and Henry. This patent includes a fiber optic light to the vicinity of the area being ground, vacuum suction to remove enamel dust, and a joint in the tool, to allow approaching from different angles.
  • U.S. Pat. No. 7,730,589 which issues Jun 8, 2010 to Dineen, covers a gel grip for power tools.

 

The development of power tools to do the work would seem to be in its infancy, judging from the lack of sophistication of products on the market, and their high prices. A $129 reciprocating saw sells for $1,290 as a dental float, after only one small modification.

Products include:

  • Flexi-Float Ultra. Rotating grinding wheel, irrigation and vacuum, variable speed. Weighs 6 pounds. $5,950. http://www.equinedentalinstruments.com/Flexi-Float-Ultra.html
  • De-MaX III Reciprocating Float. “based on a variable speed, battery powered, DeWalt 12v Max Pivoting Reciprocating Saw whose stroke has been shortened from the standard 9/16″ to 3/8″ to make it suitable for equine dentistry.” $1,295. Reciprocating float. Battery-powered. $1,295. http://www.harltons.com/Products/power_dentistry/power_dentistry.html The DeWalt saw is available on Amazon for about $129.
  • PowerFloat – Electric Model. “The Dewalt 0-4000 rpm, plug-in electric motor with a built in clutch system is designed to protect the guarded right angle grinding disc. The right angle can be positioned in the up or down position in order to do dental procedures on the upper or lower arcades. The right angle accomodates carbide chip , solid carbide, or diamond grinding discs as well as elongated carbide bits for the treatment of diastemata and periodontal pockets.” Rotating grinding wheel. Electrically powered. Weight: Price: $3,200. http://www.powerfloat.net/Products/Motorized_floats_PowerFloat_electric.html
  • PowerFloat – Cordless Quick Connect Kit #1: Basic. “Variable speed (0 to 4000 rpm) 18 volt lithium ion motor with nano technology. The cordless motor is adapted so that different shafts can be attached according to need. Included is an attachable Long Right Angle guarded shaft with diamond disc. The guarded abrasive disc (diamond or carbide) can be rotated into the up or down position for floating of the upper and lower dental arcades. The basic Quick Connect System allows the practitioner future versatility to add other attachments to the system.” Rotating grinding wheel. Powered by rechargeable battery. Price $3,600. http://www.powerfloat.net/Products/PF0004.html
  • SwissFloat – Slimline. Good pix! Rotating grinding wheel. Cordless model is powered by rechargeable battery. Price $2,320 for corded model. http://www.swissvet.com/swissfloat.htm
  • Jerry’s Quick Float. Rotating grinding wheel. $985-$1,650. http://www.equinedentaltools.com/#!power-dentistry/cmk
  • Jerry’s Eq Power Float. Rotating grinding wheel. $1,195. http://www.equinedentaltools.com/#!power-dentistry/cmk
  • The American School of Equine Dentistry. ExFloat Kit. Rotating grinding wheel. Battery powered. $2,795. http://www.amscheqdentistry.com/shop/equipment-for-sale.html

Power tools offer either a reciprocal or circular motion in the grinding surface. Most vets and equine dentists prefer the reciprocal motion for most applications, for it is mimics the reciprocal motion that they used when using a manual grinder, and it ensures that adjacent molars acquire a flat surface which is more effective when the horse chews.

Besides offering a reciprocal motion, equine vets and dentists indicate other desirable features of an equine dental float:

  • Water spray. Grinding generates heat in the grinding surface and in the surface being ground. Such heat can damage both, and should be minimized with an easily operated water spray. The equine dentist should be able to easily adjust the pressure, from off to high, with a simple movement of finger or thumb or foot pedal. Squeezing a bulb to pump water onto the teeth assumes that the typical equine dentist has three arms: a powered spray, with simple control, would be preferable.
  • Variable speed control for the grinder. The vet or equine dentist will need to control reciprocating stroke rate.
  • Brake. The equine dentist must be able to stop grinding in an instant. Some of today’s crude power tools coast to a stop, not a good thing if a problem has arisen.
  • interchangeable grinding surfaces: from coarse to smooth.
  • light weight. Some powered grinding tools require that the operator hold the tool and 18 volt rechargeable battery, with a weight of 5-7 pounds or more. Their designers must have assumed that every equine dentist had the strength and stamina of Rosie the Riveter.
  • Shield, to protect the horse’s tongue and cheeks from the reciprocating action of the grinder.
  • Clutch. The grinder must have a clutch assumbly to address the situation in which the horse has bitten down on the tool. The clutch needs to be stiff enough to deliver the force of the grinder’s motor to the grinding surface, while still being sensitive enough to disconnect the motor when a grinder is bitten. Rach et al. describe a clutch that “prevent the motor from stalling or from twisting in the operator’s hand”, but do not reference the possibility of a horse injuring itself by biting.
  • A comfortable gel grip. The reciprocating grinder will generate vibration which a gel grip could dampen, improving comfort.
  • Work light. Dentists with human patients use headlamps and powerful lamps in the examination room, but equine veterinarians often forego light and simply work from sound, because the horse’s molars are so deep within the mouth. The tool needs a light to illuminate the action in the mouth. There are lights that can be attached to the speculum used to keep the horse’s mouth open, but if a speculum is not used, the equine dentist may find an integrated work light very desirable.
  • Camera and monitor system. Looking into a horse’s mouth is a challenge, even if it is propped open with a speculum. The camera can be designed to be attached to either the grinder or to a speculum.

Claims

Claim 1. A reciprocating equine float comprising a small hand-held unit coupled to a reciprocating dental float.

  • The power for the device of claim 1 being provided by a connection to an air hose connected to an air compressor or a tank of compressed air.
  • The device of claim 1 providing a variable speed drive.
  • The device of claim 1 including a clutch that allows the float to stop or slow if it encounters too much resistance, as when a horse closes its mouth on the float.
  • The device of claim 1 includes a quick attachment mechanism for connecting any of a set of dental files/rasps/floats.
  • The housing for the device of claim 1 provides a comfortable hand grip for the dentist.
  • The housing for the device includes a trigger that may be pulled or released by the dentist’s index finger, increasing or decreasing the reciprocation rate of the dental file.
  • The trigger, when released, provides a brake, stopping the float in its current position.

Claim 2. In a preferred embodiment, the reciprocating dental file of claim 1 is partially enclosed with a removable housing to protect the bucchal cavity from accidental contact with the file.

  • The housing of claim 2 will shield the soft tissues of the horse’s mouth from contact with the sides or back of the reciprocating dental file, leaving only the rasping portion of the file exposed.
  • The housing will be composed of a sturdy stainless steel screen on each side of the dental float, with wide openings, so as not to restrict the view of the dentist. Stainless steel cross members will attach the two sides.
  • The housing will be easily attached or removed, permitting sterilization and permitting use of the device of claim 1 with or without the housing.

Claim 3. In a preferred embodiment, the device of claim 1 provides for incorporation of a water tank and sprayer for irrigating the horse’s mouth.

  • The small water tank of claim 3 may be placed on the ground or floor.
  • The water tank includes a pump below the tank, that pumps water from the tank when a trigger is activated, as on a powered pesticide sprayer. In a preferred embodiment, the battery is rechargeable.
  • The pump in the water tank cap connects to a flexible hose which attaches to the unit of claim 1 and housing of claim 2.
  • The pump in the water tank draws from the bottom of the tank, and is activated when a foot pedal is depressed, if the water pressure drops below a specified level.
  • The hose from the pump connects to the foot pedal, which in turns connects to the back of the device of claim 1 and runs forward along the housing of claim 2. At the termination of the hose in the horse’s mouth is a spray head, which causes the stream of pumped water to be distributed over the area where the reciprocating file is operating.

Claim 4. In a preferred embodiment, the device of claim 1 includes a work light to illuminate the work area in the horse’s mouth.

  • In one preferred embodiment, the light of claim 4 is a small waterproof LED flashlight which attaches to the device of claim 1, facing the reciprocating float and illuminating the entire buccal cavity.

Claim 5. In a preferred embodiment, the device of claim 1 provides for incorporation of a waterproof inspection/endoscopy camera system.

  • A number of affordable waterproof light-weight endoscope/boroscope/inspection cameras are now available. Some include transmission of video via WiFi to smartphone or tablet running an appropriate app. Such devices could be coupled to the device of claim 1 such that the camera was focused on the work area, the cable from the camera clipped to the irrigation hose of claim 3. A smartphone could be held in the dentist’s free hand; a smartphone or tablet could be mounted nearby on a floor stand.

Summary of the Invention

According to a first aspect of the invention, an equine dental apparatus for floating the teeth of horses includes a motor connected to a flexible shaft drive coupled to a reciprocating dental float. The motor may be in a backpack worn by the equine dentist, who can maneuver the float anywhere in the horse’s mouth. The preferred embodiment includes a mechanism to light and irrigate the work area, a shield to protect the buccal cavity from accidental contact with the float, and a means of incorporating a waterproof inspection/endoscopy camera system.

Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.

Brief Description of the Drawings

ThreeViews07

FIG. 1 is a top plan view of an air-powered equine dental tool in accordance with the present invention;

FIG. 2 is a side elevation view of the dental tool;

FIG. 3 is a perspective view of the dental tool.
Schematic diagram showing principle aspects of the invention. The filing surface (1) is canted up about 15 degrees from horizontal, and at the end of a shaft of about 15 inches. The file shaft inserts into an air-powered reciprocating tool with a trigger (6) that controls the variable speed, an air intake (8) connected to a compressor or tank of compressed air, and an air exhaust (9) which vents down and away from the work area. A protective stainless steel screen (2) attaches to the filer and extends just beyond the end of the filing surface (1). The screen is located on each side of the file. On the top are several stainless steel ribs that provide some rigidity to the screens on the side, without blocking the view of the equine dentist. The file reciprocates, but the housing is stationary. Its open mesh allows the equine dentist to monitor progress. Attached to one side of the screen is a water hose (3) with small spray nozzle (4). It is controlled by a foot pedal (not shown) and from there connects to a pressurized water tank. Attached to the other side of the screen is an inspection camera (7) with cable running to its control unit, which transmits video to a smart phone (not shown). A small flashlight (not shown) may be mounted on top of the main filer unit, to illuminate the work area.

Detailed Description

The present invention comprises an improved dental tool for horses and other captive herbivores. The device is powered by compressed air, running from a tank or compressor on the floor or ground through a flexible hose to a device that is held in the hand of the dentist. The hand-held device uses the compressed air to power a reciprocating dental float. The tool employs several novel principles, which singularly, and even more dramatically in combination, result in a substantial advancement in the art of animal dentistry. The tool is used to file down (float) the teeth of horses and other herbivores, including domesticated farm animals and captive animals in zoos and game parks.

One goal of this invention is to reduce the effort required to use a dental float. We achieve this, in part, by not using an electric motor at all, and by substituting compressed air for the battery that other hand-held floats require. By not using an electric motor or battery, the weight of the device is reduced from the 3.7 pound weight (product is advertised at 3.1 pounds; battery is advertised at 0.6 pounds) of a popular hand-held reciprocating dental float to 2.4 pounds.

The Filer

The filer is inspired by an existing product, the Dynabrade 12201 Stockade Reciprocating Filer.

This filer is powered by compressed air, which passes through a planetary gear, causing the float to oscillate in and out. It has a stroke length of 13/32” and a variable stroke rate up to 2400 RPM. It accepts floats that have a 1/4” diameter round shank, such as The Edge Equine for the De-MaX™ III Reciprocating Float or the Carbide Products Company MP S-1 Round Shaft Pocket Handle.

The hand-held filer provides a comfortable hand grip for the dentist. It supports one trigger for the filer and a second trigger for the irrigator.

The housing for the coupler includes a trigger that may be pulled or released by the dentist’s index finger, increasing or decreasing the reciprocation rate of the dental file. The trigger, when fully released, disconnects the coupling between the flexible shaft drive and the reciprocating float, and locks the float in its current position.

This filer meets many of our criteria:

  • The filer is light-weight, weighing only 2.4 pounds.
  • The filer comes to an immediate stop when the trigger is released, unlike a corded or battery powered reciprocating file.
  • The filer contains a clutch. If a horse were to bite down on the float, or if the float were to otherwise bind, it would come to a stop. The air that had been powering the float would simply continue to exhaust through the exhaust port of the filer.
  • The filer’s speed may be controlled with the use of a double pivot flow control using a fingertip air-flow control dial. This device swivels 360° at two pivot points, allowing the air hose to drop directly to the floor and providing improved tool handling. It improves tool maneuverability, reduces operator fatigue, and extends hose life.
  • Part # 12183 “Saw Guard Assembly” attaches to the filer with an allen bolt, and provides a base to support the Removable File Housing described below.

The Floats

Floats insert into the float chuck of the filer. They can be off-the-shelf floats designed for existing powered reciprocating floats.

Floats for existing powered reciprocating floats are available from The Edge Equine for the De-MaX™ III Reciprocating Float, are available in fine, medium, coarse, and fast versions, and fit the Dynabrade Reciprocating Filer.

The Removable File Housing

In a preferred embodiment, the reciprocating dental file is partially enclosed with a removable housing to protect the bucchal cavity from accidental contact with the file.

  • The housing of claim 2 will shield the soft tissues of the horse’s mouth from contact with the sides or back of the reciprocating dental file, leaving only the rasping portion of the file exposed.
  • The housing will be composed of a sturdy stainless steel screen, with wide openings, so as not to restrict the view of the dentist.
  • The housing will be easily attached or removed, permitting sterilization and permitting use of the device of claim 1 with or without the housing.

The Water Tank and Sprayer

In a preferred embodiment, the invention incorporates a water tank and sprayer for irrigating the horse’s mouth, flushing bits of enamel and other debris and keeping the enamel cool.

It is likely that in the course of floating one horse, that irrigation might use 3 or 4 gallons of water, and with a gallon of water weighing 8.34 pounds (3.78 kg), we recommend that the water tank be set on the ground near the dentist.

In one embodiment, the water tank is filled from the top, but drains from the bottom, through a pump powered by a rechargeable battery.

A tank, pump, and sprayer might be adapted from a commercially available sprayer, such as the Hudson 13854 Never Pump Bak-Pak 4 Gallon Battery Operated Sprayer, which is available for about $120. The adaptation would replace the hose coming from the bottom of the tank. The replacement would consiste of a piece of hose from bottom of tank to a foot pedal designed to control water flow, which would connect to another flexible hose that connected to the Filer body, and extended with a longer one that would connect to the hand held controller. The original control that operates the sprayer would be affixed to the hand held controller of the present invention. The spray wand of the sprayer would be replaced with a short length of hose that reached from the wand spray control along the side of the reciprocating float, ending near the position of the dental file in the work area.

At the termination of the hose in the horse’s mouth is a spray head, which causes the stream of pumped water to be distributed over the area where the reciprocating file is operating.

The pump in the water tank draws from the bottom of the tank, and is activated when the trigger is squeezed, if the water pressure drops below a specified level.

Illumination

In a preferred embodiment, the device includes a work light to illuminate the work area in the horse’s mouth.

The light in this invention is effectively a waterproof flashlight. It is ideally powered by a battery. In one embodiment, the batteries are located in the hand held controller. In another embodiment, the light is connected by a flexible power cable to the battery in the backpack. In another embodiment, the housing of the handheld controller includes a depression that holds a small standard flashlight.

The light itself is one or more LEDs mounted in the hand held controller, facing the reciprocating float and illuminating the entire buccal cavity. The light is turned off or on with a button on the hand held controller, or a button on the flashlight in another embodiment.

In the preferred embodiment, the light is waterproof.

Endoscopy Camera System

In a preferred embodiment, the invention provides for incorporation of a waterproof inspection/endoscopy camera system. A camera mounted near the grinder will allow the equine dentist to see the work in progress. It needs to be light-weight, work well in very low light, connect to a smartphone monitor.

A number of affordable waterproof light-weight endoscope/boroscope/inspection cameras are now available. Some include transmission of video via WiFi to smartphone or tablet running an appropriate app. Such devices could be coupled to the invention such that the camera was focused on the work area, the cable from the camera clipped to the irrigation hose. The smartphone could be held in the dentist’s free hand; the smartphone or table could be mounted nearby on a floor stand.

This should be an off-the-shelf item, a waterproof inspection camera designed for endoscopy and/or boreoscopy work. It should include WiFi, and an App that can display its image on common hand held devices, such as iPhone, Android, and iPad. The ability of the App to capture still photos from the incoming video would be a plus.

This can be accomplished with a number of reasonably priced devices, such as the Vividia WiFi Wireless 9mm Waterproof Flexible Inspection Camera Borescope Endoscope for iPhone/iPad/Android. Such devices are priced as low as $10, but we recommend the $100 DBPOWER Wifi Endoscope Inspection Camera with 8.5mm Diameter 3 Meter Tube. It supports iPad, iPhone, IOS, and Android, and includes a convenient bracket for a smartphone. See here: http://www.amazon.com/DBPOWER-Endoscope-Inspection-Diameter-Support/dp/B00HIZDM2I/ref=sr_1_17?ie=UTF8&qid=1458505255&sr=8-17-spons&keywords=Snapshot-Diameter-Inspection-Endoscope&psc=1

As compared with the prior art of US 5888064 A, the present invention offers several features and advantages:

  • Improved Operator Control. Because the work area is illuminated, and because the work area may be monitored on a variety of electronic devices (iPad, iPhone, IOS, and Android), the equine dentist has a perfect view of what is happening, even when working on rear molars.
  • Improved Horse Comfort. The water spray assures that no enamel heats up from filing, potentially damaging the enamel. The removable file housing assures that an accidental slip of the file does not damage the soft tissues of tongue, cheek, or lip.

As compared with the prior art of all devices employing a circular grinding motion, the present invention uses a reciprocating motion to ensure that grinding of the molars produces a level, smooth result, with no unevenness. The present invention grinds the teeth with the stroke method used by equine dentists who float teeth manually.

As compared with all prior art that uses electricity to power devices, the present invention is safer to use in wet circumstances (such as occur when the horse’s mouth is irrigated, and drains onto the device).

As compared with all prior art that uses electricity to power devices, the present invention is quieter. The exhaust hose coming from the filer may be directed away from the work area. And in the preferred embodiment, adapted from a Dynabrade 12201 Stockade Reciprocating Filer, there is a internal muffler to further dampen the unit’s sound.

Show 2 footnotes

  1. Eden, Scott. “The Greatest American Invention”. Popular Mechanics, July/August 2016 p. 93-99
  2. Patents Data at a Glance. USPTO.