1. The Field of the Invention
The present invention relates to dental delivery tools and components thereof for use in dentistry and medicine and other fields. More particularly, the present invention is directed to dental delivery tips and systems configured for insertion into the mouth of a patient and having a plurality of fibers disposed along a desired length of the distal delivery end portion of the delivery tip.
2. The Relevant Technology
In the field of dentistry, a fluoride composition is often applied to a patient's teeth as part of a routine dental cleaning. Fluoride compositions are often applied to children's teeth to prevent tooth decay, although they are sometimes applied to adult teeth as well. Application of fluoride has been widely recognized as a method of preventing tooth decay as it hardens the surface of enamel by forming calcium fluoride.
According to one method, a fluoride gel composition is dispensed within a dental tray, after which the tray is placed over the patient's teeth. The tray holds the fluoride gel composition adjacent to the patient's teeth. After a desired amount of time (e.g., a few minutes or less), the tray is removed, and the remaining gel composition is rinsed off the patient's teeth. Because short exposure times of the patient's teeth to the fluoride gel composition may be inadequate to delivery sufficient fluoride to have a desired effect, alternative methods that allow increased exposure time (and thus more effective tooth decay prevention) to the fluoride have been developed.
One such method involves application of a fluoride varnish composition to a patient's teeth. A typical fluoride varnish composition includes a fluoride salt dispersed within a sticky, adhesive hydrophobic varnish material. The fluoride varnish composition is typically stored within a foil covered tray, allowing the dental practitioner to peel away the cover, dip a brush into the tray, and brush the mixture onto the patient's teeth. Once applied, the varnish composition adheres to the teeth, allowing a longer exposure time (e.g., as long as, or greater than 2 hours) before the varnish composition is eroded away by the action of saliva and/or the patient's tongue.
Although such fluoride varnish compositions allow for longer exposure times, existing methods of fluoride varnish application have disadvantages. First, varnish components are typically multi-phase such that the fluoride salt is insoluble, causing the solid fluoride salt phase to settle out of the mixture during storage. Because of this, the dental practitioner is required to stir the mixture (e.g., with a stirring stick) prior to application. This mixing process requires use of an extra tool (i.e., a stirring stick), is inefficient and wasteful (i.e., the varnish adhering to the stick is unavailable for placement onto a person's teeth), and fails to ensure complete mixing.
In order to address this difficulty, an alternative method has been recently developed which preferably involves mixing the fluoride varnish composition within a two-part closed vessel (e.g., a syringe-to-syringe mixing apparatus). Once mixed, the syringes or other closed vessels can be decoupled, and the composition can be dispensed from one of the syringes. Although the composition can be dispensed through a syringe tip in this way, or through one of a variety of existing delivery tips coupled to the syringe, it would be an advantage to provide a delivery tip that could provide improved flow control of the high viscosity fluid, while also providing a wide application width for brushing the viscous composition onto the teeth.
The present invention is directed to a delivery tip and a related delivery system including the delivery tip and a container (e.g., a syringe) for use in dispensing, applying, and brushing a fluoride varnish composition or other high viscosity dental composition onto a desired surface (e.g., the exterior surface of a tooth). The inventive delivery tip includes a tip body including a passageway through which a dental composition may pass. The passageway extends from an inlet orifice at a proximal end of the tip body to a delivery orifice at a distal delivery end of the tip body. The delivery tip advantageously further includes an enlarged wing element adjacent the distal delivery end. The wing element extends substantially laterally outwardly from the distal delivery end, and is preferably planar in profile. A plurality of fibers (e.g., flocked fibers or other fibrous material) are disposed on at least a portion of the wing element. Advantageously, the ratio of the width of the enlarged wing element relative to the inside diameter of the delivery orifice is at least about 5:1.
Forming the device to include both an enlarged wing element and a relatively small delivery orifice (i.e., so that the ratio of the width of the enlarged wing element relative to the inside diameter of the delivery orifice is at least about 5:1) advantageously provides control over the flow of high viscosity composition out of the delivery orifice, while also providing for a relatively wide application width because of the enlarged wing element disposed near the relatively small delivery orifice. The small inside diameter of the delivery orifice provides control over flow of the high viscosity composition as it eliminates or reduces the tendency of a high viscosity liquid composition (e.g., a composition having a viscosity of at least about 1000 centipoise) to otherwise run or drip out the orifice absent an active driving force. In other words, the small orifice presents an environment where the liquid will not flow except when a force is applied by the practitioner. The relatively large application brushing width provided by the wing element width (e.g., about 3.5-6 mm) is particularly beneficial as this width (augmented by the length of the fibers attached to the wing element) provides an application width that closely matches the height of a typical child's molar to which the composition may be being applied.
Because the delivery tip includes a delivery orifice having a relatively small inside diameter, the delivery tip is able to control flow of a high viscosity composition as it is delivered for application. Because the delivery tip also includes a wing element extending laterally outwardly from the distal delivery end (i.e., near the delivery orifice) that is at least about 5 times wider than the inside diameter of the delivery orifice, the delivery tip is also well adapted for brushing or otherwise applying the composition in a wide application width as it exits the delivery orifice. The inventive tip advantageously is configured to apply a composition in a much wider width than a flocked applicator tip of small delivery orifice diameter that includes no wing element extending laterally outwardly adjacent the delivery orifice. Likewise, the inventive delivery tip is configured to better control the flow (i.e., by requiring an active driving force applied by the user in order to cause the composition to flow) of a high viscosity composition compared to a wider tip having a relatively large inside diameter delivery orifice.
In one example, the width of the enlarged wing element is between about 2.5 and about 12 mm, preferably between about 3 and about 9 mm, and most preferably between about 3.5 and about 6 mm. The inside diameter of the delivery orifice is relatively small compared to the width of the wing element. In one example, the delivery orifice is characterized by an inside diameter between about 0.003 and about 0.04 inch (about 0.075 mm to about 1 mm), preferably between about 0.005 and about 0.03 inch (about 0.125 mm to about 0.75 mm), and most preferably between about 0.01 inch and about 0.025 inch (about 0.25 mm to about 0.65 mm). Providing a ratio of the wing element width to delivery orifice inside diameter of at least about 5:1 provides good flow control through the orifice while simultaneously providing an application width that is substantially wider than the delivery orifice. Providing even greater ratios of wing element width to delivery orifice inside diameter (e.g., at least about 9:1, at least about 15:1, or at least about 20:1) has been found to provide for an even better combination of flow control properties and enlarged application surface width.
By way of more specific example, the most preferred range of delivery orifice inside diameter between about 0.01 inch and about 0.025 inch provides for excellent flow control properties as it requires application of a force by the practitioner to cause the composition to flow, which reduces or prevents unintentional running or dripping of the composition out of the delivery orifice, which is messy and wasteful. The most preferred range of wing element width between about 3.5 and about 6 mm is particularly advantageous as it results in an application width (wing element width plus fiber length) that closely matches the width of a child's molar, and is therefore very useful and efficient when applying the composition to a child's molars. The above ranges for delivery orifice inside diameter and wing element width correlate to a ratio of wing element width to delivery orifice inside diameter between about 6:1 and about 24:1.
Although described in the context of delivering and applying a viscous fluoride varnish composition, those skilled in the art will appreciate that the inventive delivery tips may be useful in delivering other viscous compositions (whether dental, medical, or in other fields) where control over fluid flow and a wide application width would be desirable.
These and other advantages and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.
To further clarify the above and other advantages and features of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
I. Introduction
The invention is directed to a delivery tip and a related delivery system including the delivery tip and a container (e.g., a syringe) that is particularly well suited for use in dispensing and brushing or otherwise applying a highly viscous dental composition. The inventive delivery tip comprises a tip body, including a passageway through which a high viscosity dental composition (e.g., a fluoride varnish composition having a viscosity of at least about 1000 centipoise) may be delivered. The passageway extends from an inlet orifice adjacent a proximal end of the tip body to a delivery orifice adjacent a distal delivery end of the tip body. The proximal end of the tip body is coupleable to a syringe or other container for holding and supplying a high viscosity dental composition to be dispensed through the tip. The delivery tip advantageously includes a plurality of fibers (e.g., electrostatically applied fiber flocking) attached to an enlarged wing element disposed adjacent to the distal delivery end of the tip. The wing element is relatively thin and planar and extends substantially laterally outwardly from the distal, delivery end. Advantageously, the width of the enlarged wing element is at least about 5 times wider than the inside diameter of the delivery orifice. Such a configuration provides a particularly advantageous oz combination of control over the flow of composition through the delivery orifice (i.e., because of the small inside diameter of the orifice) while also providing a relatively wide application width (i.e., because of the enlarged wing element and the plurality of fibers attached thereto) adjacent the delivery orifice.
II. Exemplary Delivery Tips and Systems
Passageway 108 (
The delivery orifice 112 is advantageously of an internal diameter sufficiently small to result in a total pressure drop along the length of passageway 108 so as to minimize or eliminate any tendency of a viscous liquid to run or drip out of delivery orifice 112 under ambient conditions absent a force intentionally applied by the user. The inventors have found that an inside diameter between about 0.003 and about 0.04 inch (about 0.075 mm to about 1 mm), preferably between about 0.005 and about 0.03 inch (about 0.125 mm to about 0.75 mm), and more preferably between about 0.01 and about 0.025 inch (about 0.25 mm to about 0.65 mm) is particularly suited for this purpose when used to dispense a fluoride varnish composition having a viscosity between about 1000 centipoise and about 3500 centipoise, more particularly between about 1700 and about 2800 centipoise.
Adjacent to distal end 104 is disposed a relatively thin, substantially planar enlarged wing element 120 that extends substantially laterally outwardly relative to longitudinal axis A. Wing element 120 includes two sub-portions 120a and 120b, each sub-portion extending laterally outwardly from opposite sides of tip body 106 such that the two sub-portions 120a and 120b are in substantially the same plane. In other words, wing element 120 advantageously extends outwardly in a substantially perpendicular direction relative to longitudinal axis A, and sub-portions 120a and 120b are substantially 180° apart (i.e., extend in essentially opposite directions). Wing element 120 is advantageously thin (e.g., between about 0.2 mm and about 1 mm), which increases bendability and flexibility of wing element 120. Wing element 120 may extend proximally any desired length. Advantageously, wing element 120 is formed so as to have a total width that is at least about 5 times greater than the inside diameter of delivery orifice 112.
The ratio of the wing element width (see
Although each embodiment illustrates delivery orifice 112 as being centrally located through the midpoint of the wing element 120, it is within the scope of the invention to shift delivery orifice 112 toward one side or the other of the wing element 120. Centrally locating delivery orifice 112 relative to wing element 120 is generally most advantageous as it provides for the best distribution of the composition as it exits orifice 112 and is caught by fibers attached to the wing element 120. In effect, such a configuration minimizes the distance the composition must travel to reach each end of the wing element 120, which facilitates good distribution of the composition throughout the plurality of fibers along the full length of the wing element 120.
In one embodiment, it may be particularly advantageous for the wing element width to provide an application width (i.e., approximately the wing element width plus twice the average fiber length) that is approximately equal the height of a person's molar to which a fluoride varnish composition is to be applied. In one such example, the wing element width is between about 2.5-12 mm, more preferably between about 3-9 mm, and most preferably between about 3.5-6 mm. The larger widths within these ranges (e.g., about 8-12 mm) may be particularly useful for applying a fluoride varnish composition to an adult's molars. The shorter widths, particularly those of about 3.5-6 mm, are particularly useful for applying a fluoride varnish composition to a child's molars.
A plurality of fibers 122 are advantageously attached to at least the distal portion of wing element 120. Fibers 122 preferably have a fiber length between about 0.3 mm and about 3 mm, more preferably between about 0.5 mm and about 2 mm. Fibers 122 may have a diameter between about 1 Denier and about 100 Denier, more preferably between about 1.5 Denier and about 10 Denier. Actual selected fiber length and diameter may depend on the viscosity, surface tension, cohesiveness, and other physical properties of the composition to be delivered through the delivery tip 100. The fibers 122 together with wing element 120 provide an application width that is approximately equal to the wing element width plus twice the average fiber length. For example, when applying a fluoride varnish composition to a child's molars, it is particularly helpful for the total application width to be between about 6-8 mm, as this is the approximate height of a typical child's molars. For an adult, the total application width is advantageously about 10-14 mm.
Fibers 122 can include short and long fibers such that longer fibers are supported by shorter fibers. The fibers may be attached to the wing element in a variety of different manners, such as through flocking, e.g., electrostatic flocking, gravity flocking, and a variety of other flocking methods. Such flocking may occur through a variety of different procedures, such as disclosed in U.S. Pat. No. 6,286,246 entitled “Electrostatically Flocked Fishing Lures and Related Systems and Methods,” which is incorporated herein by reference.
According to one flocking method, an adhesive material is applied to at least a portion of wing element 120 where fiber attachment is desired. An appropriate quantity of fibers is then contacted with the adhesive material. The adhesive is allowed to harden or cure, thereby securing the fibers to the desired portion of wing element 120. Both natural and synthetic fibers may be used. Suitable natural fibers include cotton fibers, while suitable synthetic fibers include nylon and polyester fibers. In addition, various injection moldable plastics can be employed to form the fibers of the present invention using standard injection molding techniques.
In the illustrated embodiment, the distal end of wing element 120 extends distally beyond delivery orifice 112. This configuration more easily allows a high viscosity composition exiting through orifice 112 to be caught by fibers 122, where it can subsequently be effectively applied to a selected surface (e.g., a person's molars and/or other teeth).
It will also be noticed that the delivery orifice 112 is not substantially obstructed by fibers 122 or other structure, which might otherwise impede or completely prevent the flow of a high viscosity composition through orifice 112. In other words, fibers 122 advantageously do not significantly add to the total pressure drop as fluid passes through passageway 108 and out orifice 112 as might otherwise occur if a foam or other porous plug were fitted over delivery orifice 112.
The relatively small internal diameter of delivery orifice 112 restricts, but does not completely preclude, flow through the orifice 112. For example, a typical fluoride varnish composition having a viscosity of at least about 1000 centipoise will not readily flow through delivery orifice 112 absent an expulsion pressure (e.g., applied by the dental practitioner). Advantageously, this prevents the varnish composition from running or dripping out of the delivery tip, resulting in a mess or dripping into the mouth of the patient, which could be particularly undesirable if the composition has an undesirable taste. Forming the distal portion 118 of passageway 108 so as to be of approximately the same relatively small inside diameter as delivery orifice 112 advantageously provides further control over the flow of material through orifice 112, as the small internal diameter over the length of portion 118 results in increased total pressure drop relative to what the total pressure drop would be if portion 118 of passageway 108 were of a significantly larger internal diameter, and only delivery orifice 112 were of a relatively small diameter.
Furthermore, providing a flexible, bendable distal portion within delivery tip 100 may be advantageous over a rigid and angled configuration as it allows the distal tip portion to “bounce” along the tooth surface during use. The bendability of the tip results in a certain amount of “give” or “bounce” which can provide an increased degree of comfort to the patient as compared to a rigid distal portion. This bounce characteristic also aids in reaching the interproximal spaces between the teeth because the force applied against the teeth causes the tip to bend to a decreased angle, and as the tip is pulled toward the front of the mouth the tip will bounce back from the decreased angle as the interproximal space between teeth is reached, helping the tip to press more firmly into the interproximal space so as to result in composition being deposited there.
In the illustrated embodiment of
Preferably, the distal portion of the tip is sufficiently flexible or bendable so that it can be bent to an angle between about 20° and about 70° relative to the proximal tip portion, more preferably between about 30° and about 60°, and most preferably between about 40° and about 50°. In some embodiments it may be necessary to bend the tip beyond the desired angle such that when the bending force is released, the distal portion of the tip will rebound back part way. For example, initially bending the distal tip to about 90° may result in an angle of about 45° after the bending force is released and the tip allowed to partially rebound. In other words, the bendable region may not be completely resilient which would otherwise cause the tip to return to a straight pre-bent configuration once the deforming force is released. The material and thickness of at least the flexible and/or bendable portion surrounding plane 117 is preferably durable so as to allow bending of the distal portion multiple times without cracking, splitting, or significant crazing, which may otherwise lead to premature failure of delivery tip 100. Notches 119 may be helpful in reducing any tendency to crack, craze, or split.
In the example illustrated in
Delivery tip 100′ is also illustrated as including a wing element 120′ and a delivery orifice 112′ that extend distally approximately the same length, as opposed to tip 100, where wing element 120 extends distally beyond delivery orifice 112.
In general, container 150 includes a hollow cylindrical barrel 154 (e.g., a syringe barrel) including an inner wall and a barrel outlet orifice 155, and a plunger 156 slidably disposed within hollow barrel 154 for selectively expressing the contained composition 152 (e.g., a fluoride varnish composition having a viscosity of at least about 1000 centipoise) through the barrel outlet orifice of the hollow barrel and into the inlet orifice of the tip body 100′. The illustrated embodiment further includes a cylindrical skirt portion distal to barrel 154 with internal engagement groves 114a configured for coupling with threads 114′ of delivery tip 100′. Syringe container 150 may advantageously comprise a single dose syringe. In other words, syringe 150 may be sized so as to hold a volume of composition 152 sufficient for use with only a single patient, allowing the system to be discarded after a single use.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.