FIELD OF THE INVENTION

The invention relates to dental hygiene devices and, in particular, to dental brushes.

The invention has been developed primarily with respect to dental or interdental brushes for use in cleaning gaps and spaces in a mouth such as between adjacent teeth or implants and spaces under bridges or those created by braces and for cleaning inside the pulp canal during root canal therapy, for example, and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use.

BACKGROUND ART

Dental brushes are widely known and used by both dental practitioners in a clinical setting and by people in a domestic setting to clean gaps between adjacent teeth. Dental practitioners also use the brushes to clean other spaces in a mouth such as cavities in teeth. Many different brushes have been developed, however, they typically mechanically fail under certain conditions.

An example of such a dental brush is disclosed in US Pat No. 6, 179, 617. The brush of this patent is particularly provided for cleaning the remains of a root canal after the tooth cavity space has been cleared of tooth pulp and other debris. The brushes can also be used to clean small gaps between teeth or in other spaces in a mouth. This brush includes an elongate bristles support shank extending from a manually manipulatable handle. Extending from an end of the shank distal to the handle, there is provided an elongate twisted wire support frame.

Brush bristles are spaced along the longitudinal axis of the wire support frame and extend perpendicularly outwardly from it . Individual filament bristles are provided in the US patent, however, it is known to form the bristles from a clumps or clusters of bristles. The distance the bristle tips extend in a perpendicular direction from the wire support tapers from the wire support frame distal the shank towards the handle. The taper can be any preferred rate.

Unfortunately, and in cases where there is a gap or space that is about the diameter of the bristles as is commonly the case, it is typical for the brush to experience resistance

when inserting it into the cavity or gap. This generally results in the wire support frame bending or buckling when attempting to insert the brush. It can be seen that the width of the bristles is limited by the thickness of the wire support structure which needs to be at least a predetermined amount to provide sufficient mechanical strength.

OBJECT OF THE INVENTION

It is an object of the invention to provide a dental brush that will overcome or substantially ameliorate the disadvantages of the prior art, or to provide a useful alternative.

SUMMARY OF THE INVENTION

According to an aspect of the current invention there is provided a dental brush including: a handle; an elongate brush stem extending outwardly from the handle; and a plurality of bristles spaced apart along the stem wherein the bristles extend outwardly from the stem and are inclined toward the handle at an angle of 10° to 80° relative to the longitudinal axis of the stem.

According to another aspect of the invention there is provided a method of providing a dental brush, the method including the steps of: providing a manually claspable handle; mounting an elongate brush stem to the handle such that the stem extends outwardly from the handle; and disposing a plurality of bristles along the stem such that the bristles extend outwardly from the stem and are inclined toward the handle at an angle of 10° to 80° relative to the longitudinal axis of the stem.

It can be seen that there is provided a dental brush that has bristles that can be more easily inserted into a gap or space and which provides a greater resistance to removal from gaps or cavities thereby providing an efficient cleaning mechanism. Thus, the ease of insertion reduces mechanical stresses on the brushes and hence minimises any mechanical failures. It is also observed that the bristle orientation will require a greater force to withdraw the brush from an adaptive hole than if the bristles were in

the usual perpendicular orientation, but because the wire stem or frame is in tension in this movement, no buckling will occur, and a more aggressive cleaning action will be obtained without the failure of the frame. Thus the bristle orientation allows easy insertion and reduced cleaning during the fragile compressive phase , and excellent cleaning and increased force during the crush resistive tensile phase when the wire can best cope.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 is a side view of a dental brush according to a first embodiment;

FIG. 2 is a side view of a dental brush according to a second embodiment; and

FIG. 3 is a side view of a dental brush according to another embodiment.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown a dental brush 1 including a manually manipulatable handle 2. The handle 2 extends between a near end 3 that is proximal to a user when clasped and a far end 4 that is distal the user when clasped.

An elongate metal wire brush stem 5 is mounted to the handle far end 4 and extends outwardly therefrom. The brush stem 5 extends over a predetermined length between a proximal end 6 where the stem 5 is mounted to the handle far end 4 and a distal end 7 that is remote from the handle 2.

A plurality of brush bristles 8 are spaced apart along the length of the stem 5. The bristles 8 extend outwardly from the stem 5 and are inclined by an angle, θ, being approximately 45° relative to the longitudinal axis of the stem 5. The angle of inclination θ of the bristles 8 can be in the range of 10° to 80° inclusive and is most preferably between 25° to 50°.

The distance the bristles 8 extend in a direction perpendicular to the stem 5, or the radial distance of extension, is denoted D in the drawings. In the embodiment of FIG. 1, the distance D is substantially the same for all bristles 8 along the stem 5.

The brush 1 advantageously allows for easier insertion of the brush bristles 8 into a gap or space. This results in the need for less pressure to be applied when inserting the brush. Further, the inclination angle of the brush provides a greater resistance to removal from gaps or cavities thereby providing an efficient cleaning tool being less likely to mechanically fail. It can also be seen that the brush 1 can be single or multiple use as preferred by the user. The user can be a dental practitioner using the brushes on a patient, or be a home user employing the brush 1 to clean gaps and spaces in their mouth.

A second preferred embodiment of the dental brush 1 is shown in FIG. 2. It is noted like reference numerals are used to denoted like components. In the embodiment of the brush 1 of FIG. 2, the bristles 8 extend perpendicularly from the stem 5 a (radial) distance, D, that tapers from a narrow extent at the distal end 7 of the stem to a less narrow extent at the proximal end 6 of the stem adjacent the far end 4 of the handle 2.

The rate of taper of the bristle 8 radial extension from the stem 5 is substantially the same along the length of the stem 5. The brush 1 of this embodiment is also more easily inserted into a cavity or gap resulting in the need for less pressure to be applied when inserting the brush thereby limiting mechanical failure of the brush. Further, the inclination angle of the brush provides a greater resistance to removal from gaps or cavities providing a more efficient cleaning action.

Turning to FIG. 3, there is shown another embodiment of the brush 1. In this embodiment, the distance, D, the bristles 8 extend in a direction perpendicular to the longitudinal axis of the stem 5 tapers from a narrow extent adjacent the distal end 7 of the stem 5 to a less narrow extent at some point, denoted P, intermediate the stem distal end 7 and the stem proximal end 6. The point P is approximately halfway between the proximal end 6 and the distal end 7 of the stem 5 in this illustrated preferred embodiment.

The bristles 8 disposed along the stem 5 from the point, P, to adjacent the stem " ^mvimo1 °ιnd 6 extend substantially the same distance, D, perpendicular to the al axis of the stem 5.

Although not illustrated, the brush preferably includes a cap. The cap is configured to be disposed over the stem and bristles and be releasably engagable with the handle to provide a sealed environment for the bristles. The inclination angle of the bristles can be provided in any preferred manner such as by attaching the bristles in a set angle or by bending the bristles after they are attached to the stem.

The bending can also be achieved by disposing a cap with a diameter less that the diameter, D, of the bristles over the bristles. When pushing the cap on, the bristles can be bent to a preferred orientation after being retained in the cap for a predetermined period. This can be assisted for bristles composed of a plastics material by heating the bristles to a predetermined temperature before or after pushing the cap on. Of course, the cap can be shaped to correspond to any taper in the distance D.

The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the dental arts, can be made thereto without departing from the scope of the present invention. For example, the stem 5 can be formed from a twisted pair of wires or from a plastics material. Also, the angle of inclination of the bristles 8 along the longitudinal axis of the stem 5 can differ between bristles 8 extending therealong. Also, the rate of taper of the distance D can be non-uniform. Furthermore, the bristles 8 can be individual filaments as shown, or can be clumps of filaments.