AU2004249300B2

AU2004249300B2 - Toothbrush

Info

Publication number: AU2004249300B2
Application number: AU2004249300A
Authority: AU
Inventors: Douglas J. Hohlbein
Original assignee: Colgate Palmolive Co
Current assignee: Colgate Palmolive Co
Priority date: 2003-06-20
Filing date: 2004-06-18
Publication date: 2010-09-02
Anticipated expiration: 2024-06-18
Also published as: TW201121461A; CA2842174C; RU2354311C2; CN102132995A; CA2800233C; AU2011200008A1; IN2015DN00951A; RU2370194C2; AU2011200008B2; CN103099426B; CA2800233A1; RU2006101576A; TWI371251B; RU2488330C2; RU2009121914A; RU2006101568A; CA2526830C; CA2842174A1; AU2011200008C1; WO2004112535A1

Description

TOOTHBRUSH FIELD OF THE INVENTION 1011 The present invention pertains to a toothbrush with an enhanced cleaning head. BACKGROUND OF THE INVENTION 5 1021 A toothbrush is used to clean the teeth by removing plaque and debris from the tooth surfaces. Conventional toothbrushes provided with a flat bristle trim are limited in their ability to conform to the curvature of the teeth, to penetrate into the interproximal areas between the teeth, to sweep away the plaque and debris, and to clean along the gum line. Additionally, such toothbrushes have a limited ability to retain dentifrice for 10 cleaning the teeth. During the brushing process, the dentifrice typically slips through the tufts of bristles and away from the contact between the bristles and the teeth. As a result, the dentifrice often is spread around the mouth, rather than being concentrated on the contact of the bristles with the teeth. Therefore, the efficiency of the cleaning process is reduced. 15 [02a] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim 20 of this application. 102b] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. 25 SUMMARY OF THE INVENTION [03] The invention pertains to a toothbrush with a novel arrangement of cleaning elements to provide superior cleaning of the teeth. [03a] A toothbrush comprising: 5 a handle; a head coupled to the handle and including a base surface, and a pair of opposite side edges; and a plurality of tooth cleaning elements extending from the base surface of the head, the tooth cleaning elements including: 10 a first plurality of elastomeric walls that collectively define a substantially closed loop, each elastomeric wall having a concave surface and separated from an adjacent elastomeric wall in the first plurality of elastomeric walls by a gap, the first substantially closed loop having a first center generally equidistant from the concave surface of each of the elastomeric walls of the first plurality of elastomeric walls; 15 a first central cleaning element of bristles disposed within the first substantially closed loop; a plurality of arcuate-shaped cleaning elements of bristles that collectively define an outer loop, each arcuate-shaped cleaning element having an inner concave surface defining at least an inner portion of the outer loop and an outer convex surface 20 defining at least an outer portion of the outer loop, each arcuate-shaped cleaning element separated from an adjacent arcuate-shaped cleaning element by a gap, the outer loop having a second center generally equidistant from each of the concave surfaces of each of the arcuate-shaped cleaning elements, wherein the first center and the second center are generally concentric. 25 [03b] A toothbrush comprising: a handle; a head coupled to the handle; and la a plurality of tooth cleaning elements extending from the head, the tooth cleaning elements including a first set of cleaning elements and a second set of cleaning elements, each of said sets including a plurality of arcuate cleaning elements arranged with generally opposing concave surfaces facing each other, said sets being generally 5 concentric to each other and a central cleaning element disposed in about the center of the arcuate cleaning elements. 103c] A toothbrush comprising: a handle; a head coupled to the handle, the head including a base surface; and 10 a plurality of tooth cleaning elements extending from the base surface of the head, the tooth cleaning elements including: an outer loop comprising a plurality of arcuate-shaped bristle tufts, each arcuate shaped bristle tuft having a concave surface defining an internal side of the outer loop and a convex surface defining an external side of the outer loop, and separated from an 15 adjacent arcuate-shaped bristle tuft of the plurality of arcuate-shaped bristle tufts by an outer loop gap; a first substantially closed loop being disposed within the outer loop, the first substantially closed loop including a first plurality of elastomeric arc segments, each elastomeric arc segment having a convex surface and being separated from an adjacent 20 elastomeric arc segment of the first plurality of elastomeric arc segments by a first loop gap, in which at least one first loop gap faces the concave surface of an arcuate-shaped bristle tuft of the outer loop; and a fluid pathway being defined between the convex surface of the first substantially closed loop and the concave surface of the outer loop for allowing a fluid 25 to flow therein. [041 In one aspect of the invention, a toothbrush includes a head having a plurality of tooth cleaning elements extending from a base surface. The tooth cleaning elements generally define a loop arrangement to better retain the dentifrice proximate to the lb contact between the bristles and the teeth for more effective cleaning. In one preferred construction, each loop is formed by a plurality of independently flexible cleaning elements so as to maintain user comfort and provide improved cleaning of the teeth. Ic WO 2004/112535 PCT/US2004/019851 [051 In another aspect of the invention, other c leaning elements are disposed within the cleaning elements forming the loop. In this construction, these central cleaning elements are strategically located to maximize the cleaning effect of the retained dentifrice. [06] In another aspect of the invention, tooth cleaning elements are positioned along the periphery of the head. In one preferred construction, these peripheral cleaning elements are stepped and tapered to clean along the gum line and reach the interproximal areas between the teeth. [071 The present invention also pertains to combinations of different kinds of cleaning elements on a single head that cooperate to provide a pattern for overall improved cleaning of the teeth, including effective cleaning of the rear teeth, the interproximal areas between the teeth, along the gum line, and the lingual and facial side surfaces of the teeth. BRIEF DESCRIPTION OF THE DRAWINGS [08] A more complete understanding of the present invention and the advantages thereof may be acquired by referring to the following description in consideration of the accompanying drawings, in which like reference numbers indicate like features, and wherein: [09] Figure 1 is a perspective view of a toothbrush according to one or more aspects of an illustrative embodiment; [10] Figure 2 is an enlarged plan view of a head section of the toothbrush of FIG. 1; [111 Figure 3 is an enlarged side view of a head section of the toothbrush of FIG. 1; [12] Figure 4 is a section view of the head section taken along line 4-4 in FIG. 2; [131 Figure 5 is a partial section view of the head section similar to FIG. 4 showing a tooth cleaning element arrangement in isolation for clarity; 2 WO 2004/112535 PCT/US2004/019851 [14] Figure 6 is a partial section view of the head section similar to FIG. 4 showing another tooth cleaning element arrangement in isolation for clarity; and [151 Figure 7 is a distal end view of the head section of the toothbrush of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION [161 Figures 1-7 illustrate a toothbrush 100 having a support 101 including a handle 103 and a head 105, and tooth cleaning elements 200 for cleaning the user's teeth. Handle 103 is provided for the user to readily grip and manipulate the toothbrush 100, and may be formed of many different shapes and with a variety of constructions. Head 105 is the end portion of the support provided with tooth cleaning elements 200. The tooth cleaning elements can be attached to a base surface 109 of head 105 by any known means. [17] In a preferred construction, base surface 109 is provided with at least one group of cleaning elements 209 that collectively define a loop configuration 214 to better retain dentifrice among the tooth cleaning elements 200 and specifically between the contact of the cleaning elements and the teeth. While the loop configuration is preferably a circle, it could be in the form of a myriad of different closed loops including without limitation ovals, squares and irregular s hapes. It i s b believed that t he u se o f interior c oncave w all s urfaces within the loop will best retain and move the dentifrice on the teeth especially when the toothbrush is generally moved in the desired small circular motions to brush the teeth. Nevertheless, other shapes can be used. The loop should simply define a substantially closed configuration to retain the dentifrice. [18] To better retain the dentifrice, each loop configuration is preferably defined by cleaning elements composed of elastomeric wall members. Although the loop configurations could be formed by tightly packed, elongate bristle tufts, such arrangements will permit a greater e scape o f the d entifrice than the e lastomeric w all m embers. F urther, although the 3 WO 2004/112535 PCT/US2004/019851 loop configurations could be completely closed structures, they are preferably only substantially closed and each formed by a plurality of independently flexible cleaning elements 209a-d. In this way, the cleaning elements are able to provide a limited and controlled flow of the dentifrice to the outer cleaning elements and maintain sufficient flexibility to provide greater user comfort and improved cleaning by elements 209. In the preferred construction, as seen in Figure 2, each loop construction is defined by four elastomeric wall members 209a-d each defining an arc segment that is approximately a quarter of a circle. As noted above, adjacent arc segments are spaced apart to define gaps 212 that permit a limited outward flow of dentifrice and independent flexing of each wall member. The g aps also aid the cleaning of cleaning elements 209 by permitting water to flush through the loops. The gaps, however, are preferably kept small to limit the escape of the dentifrice. While four segments have been illustrated to define each loop, other numbers of segments could be used. The wall members can be formed of any elastomeric material known for use as tooth cleaning elements. Finally, although the arc segments are preferably independent cleaning members, the loop could also be formed as a single member provided with slits to define gaps 212 and independently flexible cleaning elements 209a-d. [19] As best seen in Figure 2, the preferred embodiment includes three loops 214a-c that are each positioned front to back along longitudinal axis a-a. In this way, a large portion of the dentifrice applied to the tooth cleaning elements can be retained to clean the user's teeth. Nevertheless, one, two or more than three loops could be used. Moreover, the loops could be arranged in other patterns including non-aligned arrangements or positioned off of axis a-a. [20] In a preferred construction, a central cleaning element 207 is disposed within each loop 214; although more than one central cleaning element 207 could be provided within each loop when larger loops are used. With this arrangement, dentifrice stays near the tips of cleaning elements 207 during a brushing operation for efficient cleaning. In the preferred 4 WO 2004/112535 PCT/US2004/019851 construction, the concave nature of the inside surfaces of cleaning elements 209a-d directs the dentifrice to cleaning elements 207a-c during the sweeping or oscillating motion of head 105. [21] Central cleaning elements 207 are each preferably formed as bristle tufts for effectively cleaning the teeth. Nevertheless, one or more elastomer members may be used to form the distal cleaning elements in lieu of or in addition to the use of bristles. [22] The bristles of cleaning elements 203 as well as the bristles of other tufts discussed below are preferably composed of a nylon made from a material such as, for example, a nylon material marketed by Dupont under the name BRILLIANCE. Nevertheless, other materials could be used. The bristles in toothbrush 100 also preferably have a circular cross sectional shape, but could have other cross-sections as well. The round bristles in toothbrush may be composed on a nylon marketed by Dupont under the name of TYNEX. The diameter of the round bristles are preferably 0.007 inches - 0.008 inches thick or have other thicknesses depending on the desired cleaning action of the bristles. The tooth cleaning elements are connected to the toothbrush using known manufacturing methods for oral care products. [231 With reference to Figures 1 and 2, an additional outer ring of cleaning elements 211 a, 21 lb is disposed in a central region of head 105 in a generally arcuate arrangement about cleaning elements 209a-d of central loop 214b. These outer arcuate cleaning elements 211 a-b are preferably defined by two opposing arcuate cleaning elements which are arranged generally symmetrical on each side of the longitudinal axis a-a of head 105. As shown in Figure 2, the outer cleaning elements 211 a-b surround the loop cleaning elements 209a-d in the central region of head 105 to effectively use this space on the head. In a preferred arrangement, the loop cleaning elements 209a-d in the central region may be disposed generally concentrically within outer cleaning elements 211 a-b. The dentifrice flowing through gaps 212 in the sides of loop 214b will be used by outer cleaning elements 211. 5 WO 2004/112535 PCT/US2004/019851 While the outer arcuate cleaning elements 211 a, b are preferably defined by elongate bristle tufts for effective brushing of the teeth, they c ould be formed of one or more elastomeric members in lieu of or in addition to the bristles. [24] Figures 4-6 are sectional views of head 105 that reveal the preferred height characteristics of cleaning elements 207, 209 and 211. In the preferred construction, central cleaning elements 207a and 207c are shorter than cleaning elements 209 forming loops 214a, 214c to facilitate enhanced brushing of the lingual and facial tooth surfaces with the dentifrice retained by loops 214a, c. The difference between the first height H1 of cleaning elements 207a, c and the second height H2 of cleaning elements 209 is preferably about 0.20 2.0 mm, but there could be other variations. Central cleaning element 207b is taller than cleaning elements 209 forming central loop 214b to facilitate better interproximal cleaning as well as cleaning of the crowns of the molars. The difference between the third height H3 of cleaning element 207b and the second height H2 of cleaning elements 209 is preferably about 0.20-2.0 mm, but other variations could be used. While this construction is preferred to maximize the cleaning of various surfaces in the mouth, other variations in the heights of the cleaning elements could be used as desired. For example, central cleaning elements 207 could all have the same heights with each other and as loop cleaning elements 209, or have heights that are higher or lower than the loop cleaning elements in different ways. In another example, the central cleaning elements 209 may have heights that are higher than the loop cleaning elements 209 in a staple configuration of toothbrush 100. [25] Head 105 also includes distal cleaning elements 203a-b at the free end 107. In the preferred construction, a pair of adjacent distal cleaning elements 203a, 203b straddle longitudinal axis a-a, although they could be formed by one or more than two cleaning elements. Distal cleaning elements 203a-b protrude higher from base surface 109 than the tips of the other tooth cleaning elements. The tips of each bristle tuft 203a-b collectively 6 WO 2004/112535 PCT/US2004/019851 define an outermost cleaning surface 204 that is angled with respect to base surface 109 of head 105. By way of example, cleaning surface 204 is preferably at an angle 0 of about 30 degrees to base surface 109, but may also range between 10-50 degrees. It should be recognized that other angular values are possible. The extension and angular orientation of cleaning surface 204 of distal cleaning elements 203a-b better enable the user to reach and better clean the teeth in the back of the mouth. Cleaning elements 203a-b also can be used to dig into the crevices between the teeth and into the crown portions of the molars. Finally, as can been seen in Figure 7, the outermost cleaning surface 204 also preferably is sloped laterally downward (to form a crowned surface) to assist in the removal of debris from the teeth. [26] Peripheral cleaning elements 205a-c are positioned near free end 107 and along each side 108 of head 105. These peripheral cleaning elements 205a-c are preferably formed by a plurality of bristle tufts that are arranged generally symmetrical with respect to the longitudinal axis a-a. Cleaning elements 205a-c are positioned rearward and laterally of distal cleaning elements 203a-b. Similarly, peripheral cleaning elements 215a-c are also positioned symmetrically about axis a-a along each side 108 near proximal end 111 of head 105. These two groups of cleaning elements 205a-c, 215a-c are generally mirror images of each other, but could have other constructions. Both the distal and proximal peripheral cleaning elements 205a-c, 215a-c are generally configured to enable the user to clean along the gum line and in the crevices between the teeth. In the illustrative embodiment, three bristle tufts form each group of peripheral cleaning elements 205a-c, 215a-c. Nevertheless, more or fewer bristle tufts in these groups may be used. Further, one or more elastomeric elements may be used to define the peripheral cleaning elements in place of or with the bristles. 7 WO 2004/112535 PCT/US2004/019851 [271 As shown in Figure 3, the tips of the peripheral cleaning elements 205a-c and 215a-c protrude higher from base surface 109 than the tips of the interior cleaning elements 207, 209, 211. In a preferred embodiment, two groups of peripheral cleaning elements 205, 215 are arranged along each side 108 of head 105. Each group of peripheral cleaning elements includes three generally aligned tufts of bristles, although other numbers of tufts could be used. The center tuft of cleaning elements 205b, 215b in each group of peripheral cleaning elements protrudes outward farther from base surface 109 than the others tufts 205a, 205c, 215a, 215c. This arrangement allows deeper engagement of the tooth surfaces along the gum line with cleaning elements 205b or 215b, while stimulating the gums with cleaning elements 205a, 205c and 215a, 215c. Moreover, each of the tufts has tapered ends 206, 216 to improve the cleaning of the interproximal areas and along the gum line. [28] Proximal cleaning elements 213 a-b are positioned near the proximal end 111 of head 105. Preferably a pair of bristle tufts straddle longitudinal axis a-a, but one or more than two cleaning elements could be formed at the proximal end of the head. These proximal cleaning elements 213a,b are preferably defined by bristle tufts, but could also include or be defined by one or more elastomeric members. [29] The inventive aspects may be practiced for a manual toothbrush or a powered toothbrush. In operation, the previously described features, individually and/or in any combination, improves cleaning performance of toothbrushes. These advantages are also achieved by the cleaning elements and the synergistic effects. While the various features of the toothbrush 100 work together to achieve the advantages previously described, it is recognized that individual features and sub-combinations of these features can be used to obtain some of the aforementioned advantages without the necessity to adopt all of these features. This unique combination of elements gives exceptional cleaning power in a compact head space. 8 WO 2004/112535 PCT/US2004/019851 [30] While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims. 9

Claims

2. The toothbrush according to claim 1, wherein the head further includes a 25 longitudinal axis, and the tooth cleaning elements further comprising: a second plurality of elastomeric walls that collectively define a second substantially closed loop, each elastomeric wall in the second plurality of elastomeric walls having a concave surface and separated from an adjacent elastomeric wall in the second plurality of elastomeric walls by a gap, the second substantially closed loop 30 having a third center generally equidistant from each of the elastomeric walls of the second plurality of elastomeric walls, wherein the third center is disposed adjacent to the first center and the second center along the longitudinal axis; and a second central cleaning element of bristles disposed within the second substantially closed loop. 35 10
3. The toothbrush according to claim 2, wherein the first central cleaning element has a first height defined from the base surface and the first plurality of elastomeric walls has a second height defined from the base surface, the first height and the second height being different. 5
4. The toothbrush according to claim 3, wherein the first height is above the second height.
5. The toothbrush according to claim 3, in which the plurality of arcuate-shaped 10 cleaning elements have a third height defined from the head, the third height being above the second height.
6. The toothbrush according to claim 5, wherein the second plurality of elastomeric walls has a fourth height defined from the base surface and the second central cleaning 15 element has a fifth height defined from the base surface, the fourth height and the fifth height being different.
7. The toothbrush according to claim 6, wherein the fifth height is below the fourth height. 20
8. The toothbrush according to claim 5, wherein the second plurality of elastomeric walls has a fourth height defined from the base surface and the second central cleaning element has a fifth height defined from the base surface, the fourth height being about the same as the fifth height. 25
9. The toothbrush according to claim 2, wherein the tooth cleaning elements further comprise at least one group of peripheral tooth cleaning elements of bristle tufts along each side edge of the head and disposed adjacent and lateral to the second substantially closed loop, each said peripheral tooth cleaning element extending farther 30 from the base surface than the second plurality of elastomeric walls, and each said group of peripheral tooth cleaning elements including at least three adjacent peripheral cleaning elements, a central one of the adjacent peripheral tooth cleaning elements extending farther from the base surface than end ones of the adjacent peripheral tooth cleaning elements. 35 11
10. The toothbrush according to any one of the preceding claims, wherein at least one of the peripheral tooth cleaning elements has a tapered tip.
11. The toothbrush according to any one of the preceding claims, wherein each of 5 the arcuate-shaped cleaning elements of bristles of the plurality of arcuate-shaped cleaning elements of bristles is a continuous group of bristles.
12. The toothbrush according to any one of the preceding claims, in which the tooth cleaning elements further include at least one distal cleaning element of bristles at a 10 free end of the head, and the distal cleaning element extends farther from the base of the head than the elastomeric walls and the aruate-shaped cleaning elements of bristles.
13. The toothbrush according to claim 12, in which the distal cleaning element defines an outer cleaning surface facing generally away from the head, wherein the 15 outer cleaning surface is at an acute angle to the head and in which the outer cleaning surface slopes laterally away from a longitudinal axis of the head.
14. The toothbrush according to claim 12, in which the tooth cleaning elements further include at least one proximal cleaning element of a continuous tuft of bristles 20 disposed near where the head couples to the handle.
15. A toothbrush comprising: a handle; a head coupled to the handle; and 25 a plurality of tooth cleaning elements extending from the head, the tooth cleaning elements including a first set of cleaning elements and a second set of cleaning elements, each of said sets including a plurality of arcuate cleaning elements arranged with generally opposing concave surfaces facing each other, said sets being generally concentric to each other and a central cleaning element disposed in about the center of 30 the arcuate cleaning elements.
16. The toothbrush according to claim 15, in which the arcuate tooth cleaning elements are elastomeric wall members. 12
17. The toothbrush according to claim 16, in which the arcuate tooth cleaning elements define a substantially closed loop about the central cleaning element.
18. The toothbrush according to claim 15, in which the arcuate tooth cleaning 5 elements are a continuous tuft of bristles.
19. The toothbrush according to any one of claims 15 to 18, wherein the tooth cleaning elements further include at least one group of peripheral cleaning elements along each side of the head. 10
20. The toothbrush according to claim 19 wherein each said peripheral cleaning element is a tuft of bristles with a tapered tip.
21. The toothbrush according to claim 20 in which each group of said peripheral 15 cleaning elements includes at least three adjacent peripheral cleaning elements, wherein a central one of the adjacent peripheral cleaning elements projects farther from the head than end ones of the adjacent peripheral cleaning elements.
22. A toothbrush comprising: 20 a handle; a head coupled to the handle, the head including a base surface; and a plurality of tooth cleaning elements extending from the base surface of the head, the tooth cleaning elements including: an outer loop comprising a plurality of arcuate-shaped bristle tufts, each arcuate 25 shaped bristle tuft having a concave surface defining an internal side of the outer loop and a convex surface defining an external side of the outer loop, and separated from an adjacent arcuate-shaped bristle tuft of the plurality of arcuate-shaped bristle tufts by an outer loop gap; a first substantially closed loop being disposed within the outer loop, the first 30 substantially closed loop including a first plurality of elastomeric arc segments, each elastomeric arc segment having a convex surface and being separated from an adjacent elastomeric arc segment of the first plurality of elastomeric arc segments by a first loop gap, in which at least one first loop gap faces the concave surface of an arcuate-shaped bristle tuft of the outer loop; and 13 a fluid pathway being defined between the convex surface of the first substantially closed loop and the concave surface of the outer loop for allowing a fluid to flow therein. 5 23. The toothbrush according to claim 22 wherein the first substantially closed loop includes two sets of opposing first loop gaps, the tooth cleaning elements further including a bristle tuft disposed within the first substantially closed loop and between the opposing sets of the first loop gaps. 10 24. The toothbrush according to claim 22 wherein the at least one first loop gap is unaligned with an outer loop gap.
25. The toothbrush according to claim 22 wherein the first substantially closed loop defines an interior region, the interior region being in fluid communication with the 15 fluid pathway via the least one first loop gap.
26. The toothbrush according to claim 22 further comprising a first central bristle tuft disposed within the first substantially closed loop, wherein each elastomeric arc segment has a first height extending from the base surface and each arc segment has a 20 top surface above the base surface, and each arcuate-shaped bristle tuft has a second height extending from the base surface, the first height being below the second height.
27. The toothbrush according to claim 26, wherein a generally cylindrical cavity is defined by the top surfaces of the elastomeric arc segments and the concave surfaces of 25 each arcuate-shaped bristle tuft of the outer loop.
28. The toothbrush according to claim 22 further comprising: a second substantially closed loop including a second plurality of elastomeric arc segments, each elastomeric arc segment of the second plurality of elastomeric arc 30 segments having a concave surface, a convex surface and separated from an adjacent elastomeric arc segment of the second plurality of elastomeric arc segments by a second loop gap, wherein at least one second loop gap is generally aligned on an axis with at least one first loop gap of the first substantially closed loop. 14
29. The toothbrush according to claim 28 further comprising a first central bristle tuft disposed within the first substantially closed loop and generally disposed on the axis. 5 30. The toothbrush according to claim 29 further comprising a second central bristle tuft disposed within the second substantially closed loop, the second bristle tuft being generally disposed on the axis.
31. The toothbrush according to claim 29 wherein the head includes a pair of side 10 edges, wherein the tooth cleaning elements further include at least one group of peripheral cleaning elements along each side of the head.
32. The toothbrush according to claim 31 in which each group of peripheral cleaning elements includes at least three adjacent peripheral cleaning elements, wherein 15 a central one of the adjacent peripheral cleaning elements extends farther from the head than end ones of the adjacent peripheral cleaning elements.
33. The toothbrush according to claim 22 wherein each arcuate-shaped bristle tuft is a continuous group of bristles. 20
34. A toothbrush substantially as hereinbefore described with reference to the accompanying drawings. 15