Abstract: A dental crown preparation instrument and method for producing same includes a first body produced by grinding, the first body having a substantially cylindrical shaft and a head connected to the shaft, the first body having outer dimensions being substantially equal to the finished preparation instrument, wherein a basic toothing is at first produced in the head by grinding and a secondary toothing is produced subsequently by grinding, wherein a cutting rate of 15 to 40 m/sec is selected for the grinding process, wherein the grinding wheel is moved with a feed rate of 10 to 50 mm/min and the grinding wheels have diamond particles and have a grain size of 15 to 62 ?m, and wherein the toothings have cutting edges featuring a surface roughness of not more than 2.5 ?m.

Abstract: A disposable prophy angle for mounting on a powered dental handpiece with an elastomeric grip where the elastomer of the grip is disposed along the back of the neck, the back of the shoulder, and about the base of the device so that the prophy angle may be comfortably grasped by the fingers and thumb of a user, so that it will resist slippage from the user's hand, and so that it will tactilely direct the user's fingers and thumb into the proper position to handle the prophy angle in an effective manner.

Abstract: The present invention provides a dental polishing article having excellent polishability, which can polish dental composite resin, porcelain, dental restorative and prosthetic materials and teeth at a low cost, conveniently in a short time. More specifically, the present invention provides a dental polishing article which comprises a polishing portion formed by compounding polishing grains in an elastomer binder, and the polishing portion further comprising spherical resin particles.

Abstract: Abrasive tools (particularly dental tools), and methods of using and making such tools, wherein the abrasive tools include an elastomeric binder (e.g., one prepared from a fluoroelastomer) and agglomerate particles that include an oxide matrix (preferably, silica) and abrasive particles (preferably, diamond).

Abstract: The present invention is a prophylaxis cup having a secondary reservoir pre-filled with prophylaxis paste for a dental procedure. The secondary reservoir is separated from the cleaning portion of the cup by a dividing ring with a central orifice, the size of which will determine the flow of paste. In use, the clinician merely presses the cup against the target surface to express paste into the cleaning portion. Additional structure may be employed to further retard seepage of paste out of the cup. Being an elastomeric material, the cup may be impregnated with active ingredients to provide a substitute for additional paste.

Abstract: A prophylaxis cup formed of a silicone elastomer having perlite particles incorporated therein as an abrasive material. The silicone elastomer and perlite particles are processed in a 3-roll mill so that the perlite particles have a predetermined size and are uniformly dispersed throughout the prophylaxis cup. As the prophylaxis cup is used to clean and polish teeth, the prophylaxis cup disintegrates upon contact with the teeth releasing the perlite particles which act as a cleaning and polishing agent between the prophylaxis cup and the teeth.

Abstract: A grinding disk has a pilot region or ring that does not include abrasive material. The pilot region aids in positioning the disk between teeth or in other orientations. The disk may be used in conjunction with a guard. For example, the guard may include grip enhancements such as finger plates or cups. Guards can accommodate contra-angles. Guards made of transparent plastic improve work area visibility for a dentist or user. Some guards are made of plastic and are disposable. Embodiments of the guard may include a lubrication port for introducing a lubricant to the disk. The port may include an orifice in a wall of the guard. The port may also include a tube, for guiding the placement of a lubricating hypodermic needle and/or a hose barb for communication with a lubrication source via tubing. A disk stop in the guard can position the disk for receiving lubricant.

Abstract: This invention is a dental prophylactic polishing cup of unique design and shape having uniquely shaped turbine like ribs or vanes positioned at an angle to the long axis of the prophy cup in such a manner, that as the prophy cup is rotated, the polishing paste held in the cup and brought to bear against a tooth will be acted on by said turbine like ribs or vanes forcing the prophylactic polishing back into the cup and over a series of steps on the front inclined “working” surface of said ribs or vanes, where said steps form a series of nearly horizontal “shelves” causing the polishing paste to collect, accumulate and become entrapped, the nearly horizontal shelves, acting as/or becoming reservoirs, holding the prophylactic polishing paste inside the prophy cup, for a longer period of time.

Abstract: A denture adjustment tool having a body with a substantially oval shape, a burr having a substantially spherical shape disposed at a first end of the body, and the body and the burr having abrasive surfaces.

Abstract: According to one embodiment, an apparatus for removing enamel from a person's tooth includes a blade portion and a handle portion. The blade portion includes an abrasive surface adapted to remove enamel from the tooth in response to reciprocating movement of the abrasive surface against the enamel of the tooth. The handle portion is coupled to the blade portion, has a substantially solid cross-section, and is adapted to be inserted into a corresponding opening in a driver mechanism that is adapted to drive reciprocating movement of the blade portion to provide the reciprocating movement of the abrasive surface.

Abstract: A disposable, securely retained dental angle is provided. The angle includes a one-piece hollow housing having a short leg at its front end, which is angled with respect to the long leg. Both the short and long legs have a through bore. The short leg has an aperture, which is connected to the bore of the long leg to allow insertion of a driving shaft through the short leg of the angle. A driven rotor is inserted in the short leg. A horse-shoe-like snap rotor retainer fits within the short leg over the driven rotor to retain the driven rotor in the angle. A paw-like or, alternately, a horse-shoe-like locking means fits within the long leg over the driving shaft to lock the driving shaft in the angle and to retain the angle together. In one embodiment, a pair of splinters on the driven rotor provides the function to retain the rubber prophy cup firmly while the driven rotor is in operation.

Abstract: An endodontic file (6) including a discontinuity (18) formed within the file shank (7). The discontinuity (18) creates a safe breakage point at which the file (6) will fail prior to a failure occurring at any other point along the length (11) of the file. The safe breakage point prevents the tip (21) of the file (6) from becoming irremovably embedded in a human tooth (12) after file failure. Substantially the entire length (11) of the file (6) remains connected to the tip (21) after file failure, thereby providing a considerable portion of the file which may be gripped and manipulated in order to accomplish file removal. Empirical data is presented to permit proper characterization of the region surrounding the discontinuity (18).

Abstract: A dental diamond bur having grains of diamond attached to a head of the bur body with a plated metal layer containing grains of a fluorine compound that are almost uniformly dispersed and have an average diameter smaller than that of the diamond.

Abstract: A dental polishing tip is adapted to be coupled to a dental drive apparatus. The apparatus rotates the tip, thereby polishing the teeth. The tip includes: (i) a post having a proximal end and an opposing distal end, the proximal end being adapted to be coupled to the dental drive apparatus; (ii) an electrostatically flocked polishing head. The electrostatic flocking material on the polishing head at least temporarily increases the retention of the polishing material on the polishing head, thereby deceasing splattering.

Abstract: A specialized dental bur designed to easily enter the periodontal pocket to perform root planing and curettage without the need for incisions has a cutting head attached to a shank. The cutting head has a combined structure of a narrow, hemispherical tip, cylindrical portion of larger diameter and a transition portion having a curved surface between them. Color coding or marking enables bur segregation and enables depth determination. The bur can be used for abrading tooth root, gingiva, and bone structures without gingival incisions.

Abstract: A dental tool for use with an ultrasonic transducer, includes an elongated unitary shaft member having a longitudinal axis, a proximal end and a distal end having an outer surface, an attachment member at the proximal end to enable detachable attachment to an ultrasonic transducer; and a cutting surface defined by a plurality of grooves on the outer surface forming sharp edges.

Abstract: Systems and methods for building and using ultrasonic dental tips which provide for improved dispensing of water or other fluids at or toward the distal end (working end) of the tip. The tips utilize a water channel generally extending from before the first bend of the tip to a point prior to the working end. The water channel has improved ease of manufacture over other water transfer designs and is usable in tips having shapes where effective water transfer was previously not available.

Abstract: An abrading body (1) for treating tooth crowding, which can be introduced into interdental spaces (10) between teeth (9) and is provided with oppositely disposed working or abrading surfaces (2, 3) on both sides thereof and a shaft for attachment to a reciprocating drive mechanism (8). The abrading body (1) can be introduced vertically between the teeth (9), i.e., in the longitudinal direction thereof, and is designed to carry out an abrading movement in this direction. The abrading surface (3) is formed with a convex cross-sectional configuration. The opposite abrading surface (2) is formed with a concave cross-sectional configuration. The radius (R3) of the convex abrading surface (3) is greater than the radius (R2) of the concave abrading surface (2). An advantageous interdental contact in the form of an overlapping, dimeric, arcuate chain of teeth can be created by introducing concave and convex contact surfaces on adjacent teeth using the tooth abrading body (1) of the invention.

Abstract: A dental bleach using a bleaching agent and a polyvinylpyrrolidone thickening agent is disclosed. The bleach may include water, flavoring agents, a basic substance and desensitizing agents, as desired. Polyvinylpyrrolidone avoids acid etching and chelation of teeth that were problematic in bleaches using carbomer as a thickener.

Abstract: An ultrasonic dental instrument or tip is disclosed for performing endodontic procedures. The instrument has a hub adapted to be operatively coupled to the output of an ultrasonic handpiece and a shank portion extending from the hub. A first portion of the shank extends in a generally axial direction from the hub and tip portion extends from the first portion. The shank has a bend therein between the first portion and the tip portion ranging between about 90° and about 140°. One embodiment of the tip has an enlarged, bulbous free end, with the latter having an end face cross sectional area larger than the cross sectional area of the tip portion proximate the enlarged free end. The enlarged free end has an abrasive coating thereon so that upon activation of the instrument by the transducer, the tip portion and the enlarged free end vibrates in a plane including the shank and tip portions.

Abstract: A protective coating applied to abrasive layers of polycrystalline diamond located at the tip of abrasive dental tools is described. The protective coating is provided to protect the polycrystalline diamond layers in the course of storage, packaging, handling and sterilization. The protective coating is removable by abrasive forces when the cutting surfaces come into contact with porcelain and hard ceramic dental materials, teeth, bone or similar hard materials, and subsequently, the broken protective coating is rolled back and collected in the crevices and gaps of the polycrystalline diamond layer. The protective encapsulating coating can be made of a tough high melting point polymer layer, or a layer of a tough polymer also containing fine ceramic particles, or of a relatively soft, oxidation resistant metal or alloy.

Abstract: A method of manufacturing a polishing substrate is disclosed. The method includes disposing into a mold a reaction mixture of dibasic acid and a hydroxylated polymer, and applying a pressure and a temperature to the reaction mixture that are sufficient to cause polymerization and substrate formation in the mold. The dibasic acid is preferably adipic acid. Before pressure and temperature are applied to the reaction mixture, the reaction mixture is capable of being fortified with a polishing agent and/or a filler for controlling modulus and/or the coefficient of expansion.

Abstract: A protective coating applied to abrasive layers of polycrystalline diamond located at the tip of abrasive dental tools is described. The protective coating is provided to protect the polycrystalline diamond layers in the course of storage, packaging, handling and sterilization. The protective coating is removable by abrasive forces when the cutting surfaces come into contact with porcelain and hard ceramic dental materials, teeth, bone or similar hard materials, and subsequently, the broken protective coating is rolled back and collected in the crevices and gaps of the polycrystalline diamond layer. The protective encapsulating coating can be made of a tough high melting point polymer layer, or a layer of a tough polymer also containing fine ceramic particles, or of a relatively soft, oxidation resistant metal or alloy.

Abstract: The invention concerns a drill assembly for preparing a prosthetic crown-receiving tooth, wherein said drills (1) are of the type comprising an active part and at least an inactive part. Each of the drills (1) comprises a distal end (12) shaped like a sphere portion having an inactive part (13) and an active part (11), one of which consists of a spherical cap in apical position with a small circle (14) having a radius much smaller than its bending radius.

Abstract: A grinding bar capable of stably staying a grinding part in a minute part of an affected part to execute a grinding and treatment in an environment having a large visual field is provided. This grinding bar to be mounted on a hand piece and used for grinding a tooth comprises a shank part 12 to be mounted on the hand piece, a tapered neck part 13 provided continuously to the shank part 12, a rod part B provided continuously to the neck part 13 and narrower and longer than the neck part 13, and an arrowhead-like or piece-like grinding part 15 formed by fixing diamond particles to the tip of the rod part B.

Abstract: An ultrasonic dental instrument or tip is disclosed for performing endodontic procedures. The instrument has a hub adapted to be operatively coupled to the output of an ultrasonic handpiece and a shank portion extending from the hub. A first portion of the shank extends in a generally axial direction from the hub and tip portion extends from the first portion. The shank has a bend therein between the first portion and the tip portion ranging between about 90° and about 140°. One embodiment of the tip has a n enlarged, bulbous free end, with the latter having an end face cross sectional area larger than the cross sectional area of the tip portion proximate the enlarged free end. The enlarged free end has an abrasive coating thereon so that upon activation of the instrument by the transducer, the tip portion and the enlarged free end vibrates in a plane including the shank and tip portions.

Abstract: A dental diamond bur is provided, which is applicable for operations including from opening of a pulp chamber to spreading of a root canal orifice to any teeth of anterior teeth and molars; does not cut out a tooth orifice portion more than needed; cuts out a tooth orifice surface into a smooth curve surface form, thereby improving the adhesion between a filler and a tooth in that cut-out site; and is free from occurrence of perforation, in the root canal treatment. The dental diamond bur includes a tip portion that is a body of revolution with a convergent smooth curve, having a diameter in a shank portion side thereof of 0.5 to 0.8 mm and a height of 0.5 to 0.85 mm; and a diamond grains-attached portion that is a body of revolution with an externally convex curve from a rear end of the front end portion toward a shank portion, a maximum diameter portion of the diamond grains-attached portion being positioned in a range of 5.0 to 10.

Abstract: A dental brush has a plurality of bristles and is adapted to connect to a dental handpiece. As the brush is rotated, outer portions of the bristles shift and present an overall tapered configuration with a narrowed outer tip when the bristles come into contact with dental structure. The tapered configuration is particularly useful for finishing and polishing recesses in the patient's tooth structure such as interproximal areas, grooves located next to cusps of the teeth and recesses that may be present in dental restorations.

Abstract: A self-limiting occlusal reduction burr and method of use. The self-limiting occlusal reduction burr comprises a shank rigidly attached to one end of a conical shoulder, and a burr rigidly attached to an opposite end of the shoulder. The shank, shoulder, and burr are all axially symmetrical about an axis. A shoulder angle is defined by a shoulder outside surface and the axis, and in the preferred embodiment was 39°±20°. The self-limiting occlusal reduction burr may include indicia specifying a length of said burr and/or a diameter of said burr.

Abstract: The cleaning instrument (10) comprises a head portion (10) and, adjacent thereto, a cleaning portion (14) having a shank (20), which is provided with bristles (22) on its external surface. In order that especially the tooth root canal or also a tooth interstice can be reliably cleaned using the cleaning instrument (10), the shank (20) is of integral construction with the bristles (22).

Abstract: An abrading body (1) for treating tooth crowding, which can be introduced into interdental spaces (10) between teeth (9) and is provided with oppositely disposed working or abrading surfaces (2, 3) on both sides thereof and a shaft for attachment to a reciprocating drive mechanism (8). The abrading body (1) can be introduced vertically between the teeth (9), i.e., in the longitudinal direction thereof, and is designed to carry out an abrading movement in this direction. The abrading surface (3) is formed with a convex cross-sectional configuration. The opposite abrading surface (2) is formed with a concave cross-sectional configuration. The radius (R3) of the convex abrading surface (3) is greater than the radius (R2) of the concave abrading surface (2). An advantageous interdental contact in the form of an overlapping, dimeric, arcuate chain of teeth can be created by introducing concave and convex contact surfaces on adjacent teeth using the tooth abrading body (1) of the invention.

Abstract: The present invention relates to a dental tool, in particular for grinding teeth, comprising a grinding head and a rotatingly drivable shaft, the grinding head being provided on its surface with at least one elevated portion which, during rotation of the grinding head works a surface to be prepared and defines a circle of rotation. The invention is characterized in that the elevated portion comprises an edge, and the edge is the side line of a surface that is situated at least at the leading side of the edge and that is retracted relative to the circle of rotation defined by the edge.

Abstract: A dental diamond bur is provided, which is applicable for operations including from opening of a pulp chamber to spreading of a root canal orifice to any teeth of anterior teeth and molars; does not cut out a tooth orifice portion more than needed; cuts out a tooth orifice surface into a smooth curve surface form, thereby improving the adhesion between a filler and a tooth in that cut-out site; and is free from occurrence of perforation, in the root canal treatment. The dental diamond bur includes a tip portion that is a body of revolution with a convergent smooth curve, having a diameter in a shank portion side thereof of 0.5 to 0.8 mm and a height of 0.5 to 0.85 mm; and a diamond grains-attached portion that is a body of revolution with an externally convex curve from a rear end of the front end portion toward a shank portion, a maximum diameter portion of the diamond grains-attached portion being positioned in a range of 5.0 to 10.

Abstract: A dental bur for use in repair of a carious lesion has a working surface including cutting elements which deflect or abrade upon encountering material having a hardness at or above a preselected hardness, wherein said preselected hardness is below the hardness of normal dentin and is generally below a hardness corresponding to the lower limit of hardness of pre-carious dentin to be retained in painless procedures.

Abstract: The present invention relates to a finisher set for the cosmetic aesthetic treatment of teeth, the set comprising a plurality of finishers each including a shaft (b 5) adapted to be clamped into a drive means, as well as a conical head provided with cutting edges, characterized in that a first finisher (1) comprises a head (2) with helical cutting edges and a transverse cut, and that a second finisher (3) is provided with a head (4) having helical cutting edges.

Abstract: A rotary tool for material detaching work, especially in dentistry, comprising a machining portion having an outer circumferential surface coated with a nickel layer in which diamond particles are embedded, is characterized in that the nickel layer and the diamond particles protruding from it are covered by a layer of chromium nitride. The duration of the tool is considerably increased by the chromium nitride layer.

Abstract: A dental bur for use in examining anomalies and in restoration of decayed areas of teeth with a bur head having a generally elongate conical shaped body with a base and an opposed vertex. Cutting members are located about the outer surface of the body between the base and vertex and extend along the outer surface of the bur head which has a length of at least 1.5 millimeters.

Abstract: In the method for the manufacture of dental tools for the treatment of surfaces, a rubber core serving as a carrier layer is first applied by injection molding onto the spindle of the tool, and the abrasive layer comprising the abrasive grains is subsequently applied to the carrier layer. In another method for the manufacture of dental tools for different treatments of surfaces, more particularly for coarse grinding, finishing, and polishing, rubber-elastic masses of different degrees of hardness are used for the abrasive parts of the tools according to the intended treatment, and abrasive grains of the same size are embedded in the rubber-elastic mass of these parts.

Abstract: The present invention relates to a grinding tool for dental purposes comprising a support body which is covered at least in part with abrasive material, wherein at least a portion of the support body is provided with a honeycomb structure.

Abstract: A dental tool that has a thin disc covered with an abrasive material. The disc has a flange portion and coupling device is formed adjacent to the flange portion for attaching the disc to a drive device. The drive device spins the disc to treat a dental surface. The thickness of the disc may decrease from a central portion of the disc toward a peripheral edge of the disc. The disc may be interspersed with an abrasive material integrated into the disc by an elastic bond.

Abstract: A dental tool having a processing section at one end which includes a longitudinally extending lateral face and a transversely extending front face having an abrasive working face located at a distance from the lateral face so as to permit forming a precise marginal edge around a tooth to permit precise positioning of a crown while avoiding deleterious working of the tooth region nearest the stump on which the crown is to be mounted.

Abstract: A pair of dental burs for shaping mandibular teeth into the proper sloped configuration for lingual occlusion or denture teeth. The first bur is provided with a non-cutting central portion that is flanked by two slightly angled cutting surfaces, and the second bur is provided with a cutting central portion that is flanked by two slightly angled non-cutting surfaces. The angulation of the two cutting surfaces on the first bur may or may not match each other on a given set of burs, and the angulation of the two non-cutting surfaces on the second bur may or may not match each other on a given set of burs, but the angles of the cutting surfaces on the first bur match the angles of the non-cuffing surfaces on the second bur. The burs are used sequentially; i.e. the first bur is used first and the second bur is used second, to achieve the desired slope and center floss for the mandibular teeth without cutting too deeply.

Abstract: A prophylaxis cup is provided which has a lower portion and an upper portion. The lower portion of the cup is adapted to mount the cup to a driven member of a prophylaxis angle. The upper portion of the cup includes a wall having an inner surface and an outer surface. The inner surface is smooth and uninterrupted and defines a cavity having a floor and which receives prophylaxis paste. A central post extends up from the cavity floor. A continuous, uninterrupted, circumferential flange extends inwardly from a top of the wall's inner surface. A sloped working surface extends between the flange inner edge and the wall outer surface. The cup is pre-formed to define a flare or annular wedge at the outer edge of the working surface which is sized to permit the working surface to clean a tooth subgingivally and interproximally. A generally circular groove on the working surface helps hold the prophy paste. The groove spirals outwardly.

Abstract: A dental bur has a working surface including cutting elements which deflect or abrade upon encountering material at or above the preselected hardness corresponding to the lower limit of hardness of non-carious dentin. The dental bur is constructed of metal, ceramic, or plastic.

Abstract: A disposable right angle dental handpiece comprising a plastic housing having a sleeve, a tapered neck, a head and a disposable prophy cup. The cup being removably coupled to a driven rotating member located in the head section for simultaneously cleansing the surface of the teeth as well as the surrounding tissue and gingival crevice. The sleeve having an elongated opening for receiving a power drive from a dental unit. A gear ratio mechanism located in the sleeve, rather than in the head section, for increasing the shaft speed by a factor of two to three times. A gear to gear arrangement in the head section for transferring the directional rotation from the drive shaft to the prophy cup. The prophy cup comprising a flexible body having a cavity therein with a plurality of concentric rings made of cloth or felt material for holding the cleansing paste and also to avoid splattering.

Abstract: In a dental prophylaxis angle, an angle housing defines a main passageway and an ancillary passageway communicating therewith and extending at an substantial angle thereto. A drive shaft extends through the main passageway, while a cup holder is rotatably disposed in the ancillary passageway, the cup holder being drivingly coupled to the drive shaft. A flexible prophy cup is mounted to the cup holder, and a bearing is rotatably disposed in the main passageway about the drive shaft. The bearing has a snap-lock element projecting into a recess provided in the housing, thereby fixing a longitudinal position of the bearing with respect to the housing and holding the drive shaft in driving engagement with the cup holder. The prophy cup is coupled to the cup holder via a ball and socket joint and is provided in a region about the ball and socket joint with a flexible skirt defining an annular groove, the cup holder having an annular seat projecting into the groove.

Abstract: System for the removal of a defect in a tooth (71), consisting of an oscillatingly movable tool (3) having working surfaces (56) for an abrasive making of a cavity (K) in the tooth, a filling material for filing the cavity (K), an insert (91, 91A) which can be placed into the cavity (K), which with regard to its surface region surrounded by the cross-sectional walls (KW) of the cavity (K) is pre-fabricated adapted to the dimension and shape, and a binding material (92), which hardens or cures, for bonding the insert (91, 91A) with the walls (KW) of the cavity (K).

Abstract: The dental device comprises an abrasive disk having a hub made of synthetic material and a spindle with a collet, the opening of the hub having an inner bead and the collet a rotation lock and an axial lock for receiving said bead in the hub opening, the greatest diameter of the spindle with its rotation lock being greater than the diameter of the hub opening with its bead. This construction allows, on one hand, an easier mounting of the abrasive disk on the spindle, and, on the other hand, a high torque transmission.

Abstract: A dental debridement tool is provided for use with a rotary dental handpiece to remove a surface contaminant from a surface of a tooth. The tool includes a shaft extending along an axis and having a proximal end and a distal end. The proximal end is sized and shaped for connection to the rotary dental handpiece. The tool also includes an operative tip being carried at the distal end of the shaft. The operative tip has a length parallel to the axis. The length is at most 8.0 millimeters and the operative tip is no wider than 4.0 millimeters at any point along the length. The operative tip is operably compressible during removal of the surface contaminant and includes an abrasive composition of matter. The abrasive composition may include polystyrene, polyethylene, polyester, acrylic, or silicone. An abrasive powder may be included in the abrasive composition. The abrasive powder may include pumice, mica, diamond, talc, aluminum oxide, tin oxide, silicone oxide, or a ceramic material.

Abstract: The invention provides for the incorporation of dentifrice preparations, which are commonly accessed from a container on a tray during teeth cleaning, internally within the housing of a disposable prophy angle. Auger, baffle or piston members are used to move the preparations from the housing through passages in the head of the prophy angle to a moving prophy cup. If a reusable autoclavable prophy angle is being used, the invention provides for an annular chamber containing the dentifrice preparation that interfits as a sleeve over the prophy angle body. In such case, the prophy angle head is enlarged and includes an inlet connection with the annular chamber. Passageways in the head direct the dentifrice preparation to the prophy cup and a piston ring is used to move the dentifrice preparation from the chamber through the passageways. Alternatively, an external pressurized supply of the dentifrice preparation may be connected to a conduit which is attached to the body in place of the annular chamber.