Patent Application
20110030160
The present invention relates to toothbrush bristle profiles. More particularly, the present invention relates to unique bristle tuft profiles.
Toothbrushes generally have a plurality of bristle tufts, each tuft having a plurality of bristles, for removing plaque and debris from tooth surfaces. Typically, bristle tufts are configured for brushing the outer surfaces of the teeth, i.e., the buccal (cheek-facing), lingual (tongue facing), and occlusal (chewing) surfaces of the teeth. Dental floss is effective in removing plaque and debris from interdental or interproximal surfaces. However, not all individuals floss on a regular basis, and some individuals hardly floss at all. Accordingly, it is desirable for toothbrush bristle profiles (the contour of the free cleaning/brushing/tooth-engaging ends of the bristles as seen from a side elevational view) to be designed to remove plaque and debris not only from the outer surfaces of the teeth but also from the interdental surfaces of the teeth. Massaging and stimulating the gums is also considered to be beneficial to good dental health. Accordingly, it also is desirable for toothbrushes to provide gum and interdental stimulation as well as good interdental cleaning.
Commercially available toothbrushes with flat bristle profiles (i.e., all free ends of the bristles are on substantially the same level or, in other words, are coplanar) clean the outer surfaces of teeth adequately, but are not as adept at cleaning interdental surfaces and providing interdental stimulation as are toothbrushes with contoured bristle profiles (having free ends at differing heights). Various bristle profiles, such as a repeating “V”-shaped (aka, sawtooth or zig-zag) profile, are known to increase the cleaning and gum-stimulating efficacy of toothbrushes.
Commercial toothbrushes typically have a brushing surface area (the surface area occupied by bristle free ends) of approximately 1 to 1.25 inches (25.4 to 35.8 mm) long and 5/16 to ⅜ inches (7.9 to 9.5 mm) wide. The bristles are generally arranged in 4 to 6 longitudinally extending (i.e., from the distal to the proximal end of the head, or, in other words, from the tip of the head towards the handle) rows of bristle tufts with 5 to 14 tufts per row, and approximately 20 to 50 bristles per tuft. Typical tufts are approximately 0.063 inches (1.6 mm) in diameter, with a cross-sectional area of approximately 0.079 inches2 (2 mm2). The diameters of commonly used bristles are: 0.006 inch (0.15 mm) for soft bristles, 0.008 inch (0.2 mm) for medium bristles, and 0.010 inch (0.25 mm) for hard bristles. The diameter of the bristles used in the brush, or increasing the tuft area, generally increases the stiffness of the bristles or tufts, and generally extends the life of the brush. However, such increases generally negatively affect the interdental cleaning of the brush, as well as the wear on the gums because the bristles are not as readily moved or bent to fit in the interdental spaces.
Accordingly, there is a continuing desire to improve the interdental cleaning ability of toothbrushes, especially since many individuals do not floss. Moreover, there is a desire to increase the life of the brush.
In accordance with the principles of the present invention, a toothbrush is formed with a bristle profile providing superior interdental cleaning. In accordance with one aspect of the present invention, at least one bristle tuft is provided with a greater number of bristles than in typical bristle tufts and with a brushing surface area greater than typical bristle tufts, such large bristle tuft being contoured to provide superior interdental cleaning. In particular, the large bristle tuft has at least two raised sections of bristles separated from one another by shorter bristles. The large bristle tuft has a sufficient number of bristles to impart increased stiffness, rigidity, and cleaning power typical of larger-area bristle tufts. However, because the raised sections are isolated from one another, such sections have the flexibility and interdental reach of typical bristle tufts having fewer bristles than the larger-area bristle tuft. The raised sections of the large bristle tuft can sweep around teeth and reach interproximal areas, and the lower sections of the large bristle tuft polish the outer surfaces of the teeth.
In accordance with another aspect of the present invention, a toothbrush may be formed with bristle tufts of standard brushing surface area, each bristle tuft being contoured to have a substantially conical or frustoconical profile. Moreover, the heights of the tallest or highest bristles in the conical bristle tufts vary along the brushing surface area of the toothbrush. Accordingly, such bristle tufts are contoured for ready interdental cleaning yet are at different heights and spaced from one another for even better opportunities to reach interdental surfaces of the user's teeth.
While the specification concludes with claims which particularly point out and distinctly claiming the invention, it is believed the present invention will be better understood from the following description of several particularly preferred embodiments taken in conjunction with the accompanying drawings, in which like reference numerals identify similar elements and wherein:
An exemplary toothbrush 100 to which the principles of the present invention may be applied is illustrated in
Toothbrush head 110 has a head surface 112 from which bristles 114 extend. Bristles 114 may include a toe tuft 116 at the proximal-most end of head surface 112 configured for reaching a user's back teeth. Typically, a toe tuft is a larger bristle tuft that preferably has an angled contour, such as illustrated in the exemplary embodiment of
The exemplary toothbrush illustrated in
The bristle profile (i.e., the profile of the cleaning ends or free ends of the bristles, as seen from a side elevational view) of a toothbrush formed in accordance with the principles of the present invention is configured to provide superior interdental cleaning. The individual bristles used to achieve the inventive bristle tuft profile may be generally circular in cross-section, with individual bristle diameters of between about 0.004 inch (0.1 mm) and about 0.014 inch (0.4 mm). However, other cross-sectional bristle shapes such as oval, square, rectangle, hexagonal, plus-sign, star, etc., are also contemplated. Bristles are typically made of synthetic fibers, such as nylon 6.12. The free cleaning ends of the bristles may be formed in any desired manner, such as straight-cut, rounded, tapered, or otherwise contoured. It will be appreciated that the individual bristles need not all be identical to one another. For instance, bristles of different diameters or cross-sectional shapes may be provided on a toothbrush head 112 of a toothbrush 100 formed in accordance with principles of the present invention.
Typical average or standard bristle tufts, composed of a plurality of bristles, are approximately 0.063 inches (1.6 mm) in diameter, with a cross-sectional area of approximately 0.079 inches2 (2 mm2). Larger tufts are commonly provided as toe tufts at the distal-most end of a toothbrush head (or heel tufts at the proximal-most end of a toothbrush head closest to the handle), and may be found at other locations along a toothbrush head to provide more powerful cleaning ability than standard bristle tufts with fewer bristles. In accordance with one aspect of the present invention, at least one such large tuft having a brushing surface area (surface area occupied by brushing or free ends of the bristles) larger than a standard or typical toothbrush bristle tuft is contoured to form a contoured large tuft 120 having a raised section configured for reaching interdental tooth surfaces. A contoured large tuft 120 formed in accordance with the principles of the present invention is larger in area than average tufts on toothbrushes known in the art. Average tufts have a cross-sectional area of about 2 mm2. The contoured tufts of the present invention have a cross-sectional area preferably greater than at least about 4 mm2, more preferably greater than at least about 5 mm2, and most preferably greater than at least about 10 mm2.
Because contoured large tuft 120 has a larger brushing surface area than provided by average or standard bristle tufts, contoured large tuft 120 has more bristles than commonly provided in a standard bristle tuft and thus does not flex as readily or as much as a bristle tuft having a standard surface area and formed of bristles of the same diameter as in contoured large tuft 120. Accordingly, the bristles of contoured large tuft 120 have the stiffness, rigidity, and cleaning power of a larger tuft because of the lateral reinforcement provided by the bristles making up contoured large tuft 120, while allowing more targeted cleaning action than heretofore permitted by larger tufts. Contoured large tuft 120 is contoured to have at least one raised section 122 of bristles having heights extending above the heights of the bristles remaining in lower section 124 of contoured large tuft 120. A sufficient number of bristles of raised section 122 have brushing ends that are not laterally supported by the other shorter bristles of contoured large tuft 120 and extend above the heights of the other bristles in contoured large tuft 120 to reach into interdental spaces and clean interdental tooth surfaces efficiently. Accordingly, the bristles of raised section 122 have the flexibility and interdental reach of a smaller bristle tuft. Nonetheless, because the bristles of raised section 122 are laterally supported by the other bristles of contoured large tuft 120 at a level close to head surface 112 (i.e., at the lower region or adjacent the bases of the bristles), lateral shifting is still lower, on average, than that which may occur if such raised section were an independently formed interdental tuft.
As will be appreciated, a contoured large tuft 120 formed in accordance with the principles of the present invention can sweep around teeth and reach interproximal areas (via raised section 122) while also simultaneously polishing outer tooth surfaces (via lower section 124). For purposes of the present invention, a raised section 122 of a contoured large tuft 120 formed in accordance with principles of the present invention is a section having free cleaning ends extending above other bristles of that tuft. Also for purposes of the present invention, a lower section 124 of a contoured large tuft 120 formed in accordance with principles of the present invention is a section having free cleaning ends below the free cleaning ends of other bristles in that tuft. Because contoured large tuft 120 may include bristles of varying heights (all bristles are not necessarily either the tallest or the shortest, but may have a height in between the tallest and shortest bristles), the lowest section may also be referenced as the base section.
In accordance with one aspect of the present invention, the cross-sectional cleaning area provided by raised section 122 of contoured large tuft 120 is sufficient to achieve the desired cleaning, particularly interdentally. Preferably, a raised section 122 having a brushing surface area of at least about 0.25 mm2 is believed to provide the desired interdental cleaning. Preferably, raised section 122 has a brushing surface area of less than about 4 mm2. A raised section 122 with brushing surface area of about 1.5 mm2 has been shown to provide the desired improved cleaning efficacy.
In accordance with another aspect of the present invention, which may or may not be combined with the above-described aspects, more than one raised section 122 is provided within contoured large tuft 120. In order for the raised sections 122 to have the desired interdental cleaning ability, the raised sections 122 preferably are spaced apart from one another by bristles in lower section 124. More particularly, the free cleaning ends of raised sections 122 preferably are spatially isolated from one another so that each raised section 122 may function independently of the other raised sections 122. Preferably, a sufficient number of lower bristles are provided between raised sections to permit the separate raised sections to act independently. Alternatively, or additionally, the spacing between the separate and independent raised sections 122 may be determined by the brushing surface area provided between the separate and independent raised sections 122. Optionally, the number of or surface area of lower bristles provided between separate and independent raised sections 122 is also selected to permit the lower bristles to efficaciously clean outer surfaces of a tooth while the raised sections clean interdental surfaces. Preferably, raised sections are spaced apart from one another by at least 0.2 mm, and preferably at least 0.5 mm. It will be appreciated that lower section 124 may have regions that are isolated from one another such that lower section 124 may also be described as having one or more sections. However, for the sake of simplicity, reference is made to only a “lower section” with the understanding that such reference includes a single interconnected group of lower bristles as well two or more isolated sections of lower bristles.
Turning now to
As may be seen from the schematic plan view of
Of course, instead of having gap regions 234 where no bristles are provided, shorter bristles may be provided in the areas indicated in
It will be appreciated that a contoured large tuft 120 formed in accordance with the principles of the present invention may have footprint shapes other than the “X” or “+” shape of exemplary contoured large tuft 120 of
A branched contoured large tuft may be formed with other numbers of branches than those described above. In accordance with the principles of the present invention, exemplary contoured large tufts 420a, 420b, and 420c of
In the exemplary embodiments illustrated schematically in
As will thus be appreciated, the footprint shape of a contoured large tuft as well as the individual raised sections of such contoured large tuft formed in accordance with principles of the present invention may be any desired shape (e.g., rectangular, oval, star-shaped, ring-shaped, etc.) that achieves the desired efficacious cleaning and preferably, in particular, simultaneous interdental as well as outer tooth surface cleaning. For instance, a contoured large tuft formed in accordance with principles of the present invention may have a substantially circular footprint shape, such as exemplary contoured large tufts 620a, 620b illustrated schematically in
In accordance with the principles of the present invention, it is desirable for raised sections 122, 222, 322, 422a, 422b, 422c, 522a, 522b, 522c, 622a, and 622b (for the sake of simplicity, reference hereinafter will be made only to raised section 122 with the understanding that similar principles or descriptions may be applied to the other raised sections of the other embodiments) to be sufficiently raised above respective lower sections 124, 224, 324, 424, 424, 424, 524, 524, 524, 624, 624, 624 (for the sake of simplicity, reference hereinafter will be made only to lower section 124 with the understanding that similar principles or descriptions may be applied to the other lower sections of the other embodiments) to differentiate these two sections functionally from each other by imparting different functional capabilities to these two sections. The portions of the bristles of raised sections 122 extending above the free cleaning ends of lower section 124 preferably are sufficiently long enough to reach adequately into the interdental spaces between teeth while (and preferably at the same time) the free cleaning ends of the bristles of lower section 124 reach the outer surfaces of the teeth. In accordance with the principles of the present invention, a sufficient brushing surface area is provided by a raised section 122 that extends sufficiently above surrounding bristles of contoured large tuft 120 to reach into interdental spaces and to clean interdental surfaces. The highest bristle in at least one of the raised sections 122 of a contoured large tuft 120 formed in accordance with the principles of the present invention is preferably at least about 0.5 mm higher and not more than about 4 mm higher, and more preferably at least about 1 or 2 mm higher, and most preferably about 1.8 mm higher than the lowest group of bristle in lower section 124 of that contoured large tuft 120.
As may be appreciated from the above descriptions of exemplary contoured large tufts formed in accordance with the principles of the present invention, the height of bristles in the raised sections of the contoured large tuft are not necessarily all the same height. Instead, one or more of the raised sections may have a tapered profile. Such tapering may occur in any desired direction, such as to achieve a particular functional effect. The tuft profile of the sections of contoured large tufts formed in accordance with principles of the present invention may be selected to increase the number of bristles contacting the user's teeth at the same time. For instance, the tuft profile of at least the raised section may be curved so that when bristles of a raised section reach interdentally between the teeth, tapering of the raised section allows bristles simultaneously to contact the curving tooth surface. In other words, although brush head 112 generally will not be the same distance from one point on a tooth surface as to another point on a tooth surface, the differing bristle lengths compensate for such varying distances between brush head 112 and points along the tooth surfaces. More than one taper, in different directions, may be provided to increase bristle free cleaning end contact with teeth during cleaning regardless of the brushing direction. For instance, as may be seen in
In accordance with a separate and independent aspect of the present invention, a plurality of bristle tufts may be formed to each have a contoured profile, with the various contoured bristle tufts being at different heights from one another. Such tufts may be of standard cross-sectional area. The bristle tufts may be contoured in any desired manner to achieve a desired cleaning effect or efficacy. For instance, the bristles in a given bristle tuft may be of different heights to form a substantially conical or frustoconical profile facilitating interdental cleaning. Bristles in other bristle tufts may be of different heights to form a concave profile that may better conform to the convex buccal and lingual tooth surfaces. The difference in heights of the various contoured bristle tufts may be selected to achieve a desired cleaning effect or efficacy as well. For instance, longer or higher tufts are desirable for interdental cleaning, whereas shorter or lower tufts are desirable for cleaning outer tooth surfaces, particular buccal and lingual tooth surfaces. The differences in heights between such contoured bristle tufts may be measured, for instance, by comparing the highest bristles of the contoured bristle tufts. The height difference between the contoured bristle tufts of varying heights 140 may be at least about 1.5 mm and preferably about 1 mm. Contoured bristle tufts of varying heights 140 may be arranged within a central region of the brushing surface area or footprint of the toothbrush head 110, as illustrated in the exemplary toothbrush heads of
Alternatively, or additionally, the contoured bristle tufts of varying heights 140 may be arranged such that the height differences occur not only along longitudinal direction L of toothbrush head 110 (such as sawtooth patterns common in the prior art), but also along transverse direction T of toothbrush head 110. The exemplary embodiment of
In accordance with yet another aspect of the present invention, contoured bristle tufts of varying height 140 may be interspersed with bristle tufts having different contours or no contour at all (i.e., the cleaning free ends of all bristles being at substantially the same height), and/or bristle tufts with different brushing surface areas, such as a large tuft (like contoured large tuft 120). It will be appreciated that the bristle tuft arrangement of
A toothbrush may be formed in accordance with the principles of the present invention using methods similar to those disclosed in U.S. Pat. No. U.S. Pat. No. 5,609,890, issued to G. B. Boucherie N. V. on Mar. 11, 1997, or U.S. Pat. No. 6,582,028 issued to M C Schiffer GmbH on Jun. 24, 2003, which patents are hereby incorporated herein by reference in their entireties.
Various embodiments of toothbrushes formed in accordance with the principles of the invention have been described above. Each embodiment is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents.
The present invention may be better understood with reference to the following examples.
Three toothbrushes were constructed. The first toothbrush was constructed with three cross-shaped tufts as laid out in
Simulated plaque was applied to a human jaw model in the area between the teeth. Three hundred grams of force was applied to each head to push the bristles against the teeth, and the toothbrush was moved back and forth by a machine for eight seconds to simulate brushing. The amount of simulated plaque left behind was then assessed compared to a control to determine how much was removed based upon the toothbrush head design. The table below summarizes the results:
The table shows the significant improvement when cross-shaped tufts with bristles a height difference of 1.2 mm are used to clean the teeth. Adding toe and conical tufts is shown to slightly improve plaque removal.
The exemplary embodiment illustrated in the figures has several separate and independent inventive features, which each, at least alone, has unique benefits which are desirable for, yet not critical to, the present invention. Therefore, the various separate features of the present invention need not all be present in order to achieve at least some of the desired characteristics and/or benefits of the present invention. One or more separate features may be combined, or only one of the various features need be present in a formed in accordance with the principles of the present invention, whether or not explicitly indicated. Therefore, the present invention is not limited to only the embodiments specifically described herein.
While the foregoing description and drawings represent exemplary embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope of the present invention. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other specific forms, structures, arrangements, proportions, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will appreciate that the invention may be used with many modifications of structure, arrangement, proportions, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of elements may be reversed or otherwise varied, the size or dimensions of the elements may be varied. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, and not limited to the foregoing description.
