EP0281017B1 - Toothbrush - Google Patents

Abstract

While brushing the teeth with known toothbrushes, whether manually or mechanically operated, the user can involuntarily apply too much pressure, which may cause damage with far-reaching consequences to the gums, teeth and dental fixing devices. Such damage may be avoided by using a toothbrush which enables the user to achieve optimum pressure for brushing the teeth by simple means, and without using additional electrical or electronic aid. The head (3) of the toothbrush is so disposed on the shaft (1) of the toothbrush, that it flexes when a certain level of pressure is reached, enabling optimum pressure to be maintained while the teeth are brushed. An acoustic and/or tangible sign may be given when optimum pressure on the shaft (1) of the toothbrush is reached, or the shaft (1) may be formed at certain points like a leaf spring, in such a way that the flexible design of the toothbrush head ensures that an optimum or maximum pressure while brushing the teeth is not exceeded.

Description

The invention relates to a toothbrush for manual or mechanical actuation, the brush head of which is connected to the brush shaft via a deflection section, which allows the brush head to be deflected with respect to the brush shaft at a predetermined contact pressure.

Optimal oral hygiene means removing existing dental plaque (microbial plaque) and food residues and preventing these pathogenic plaque. A pleasing increase in oral hygiene awareness is offset by well-intentioned, but primarily too force-intensive brushing measures, which are increasingly accompanied by frightening damage on a scale of acute and chronic brush trauma: exposed tooth necks (gingival recession), stab injuries caused by toothbrush bristles in the gums (acute brush lesions), gaps in the gums (breast formation) Gaps), wedge-shaped loss of substance in the area of the root near the crown of the tooth (wedge-shaped defects), whereby the rate of loss of tooth substance can be increased by the usual increasing consumption of acidic foods and drinks with subsequent brushing measures (erosions). The principle of action of these pathological manifestations is based on the transfer of excessive forces when brushing over the gums (gingiva) to the bones of the tooth support system (limbal alveolar bone), which is then reabsorbed. After losing its bony surface on the tooth root, the gums become atrophied and the exposed tooth neck is created. In extensive, computer-assisted examinations, excessive force transmission as the main etiological factor of these acute and chronic brush injuries was clearly identified.

A toothbrush of the type mentioned is known from US-A-4,520,526. This document shows a toothbrush which has a deflection section between the brush head and the brush shaft, which is flexible in a vertical plane, that is to say in a plane parallel to the bristles, and which yields in accordance with the applied contact pressure.

US-A-2 083 217 shows and describes a tooth cleaning device which is not actually a toothbrush but is intended to allow teeth to be cleaned without toothpaste. Between the brush head and the brush shaft can be Spring may be provided, which enables an elastic deflection of the brush head in accordance with the applied contact pressure.

FR-A-1 247 433 discloses a toothbrush in which the brush head is divided into three strips in the longitudinal direction of the toothbrush. The middle strip is reinforced by a stiffening rib so that the side strips give way earlier than the middle. This is intended to enable the rows of bristles to be used particularly cheaply.

From DE-C-34 14 623 an electric toothbrush is known which allows the user to control the contact pressure with the help of an integrated electronic device. When the specified contact pressure is reached, an optical or acoustic display is heard.

The invention has for its object to provide a toothbrush with which the user is able to maintain the optimal contact pressure for brushing teeth in a simple manner without additional electrical or electronic aids.

This object is achieved according to the invention in a toothbrush of the above type in that the profile section has a profile cross section which is designed such that it allows a sudden deflection of the brush head when the predetermined pressing force according to the snap frog principle is reached.

Characterized in that the brush shaft is formed at a suitable point with a special profile cross-section, which allows a preferably sudden mechanical deflection of the brush head when reaching a certain contact pressure, the prerequisite is created in a particularly simple and advantageous manner for the brushing force applied by the patient only up to a specified maximum limit to take effect. If this maximum limit is reached, it deforms beforehand curved deflection profile of the brush shaft suddenly becomes an elongated profile with a correspondingly changed stiffness, the characteristic of this change in stiffness being variable within wide limits due to the curvature, the material properties and the material thickness of the deflection profile. With a thin, strongly arched profile cross-section, high forces can be achieved up to the deformation limit with the subsequent greatly reduced transmission possibility.

If, on the other hand, the deflection profile of the brush shaft is formed only with a slight curvature but with a larger profile cross section, this effect is weakened so that every transfer characteristic of the brushing force can be achieved by varying the curvature, the profile cross section and / or the material used. It is also possible to provide the transmission characteristic with different levels by coupling two or more different deflection profiles, e.g. to reach two "sticking points" with different forces. This makes it easy to display a contact pressure that is too low or too high with any desired bandwidth.

Toothbrushes with this groundbreaking innovation are to be widespread among patients, especially among young adults; Because epidemiological studies on a representative number of 18 to 22 year old young people prove that they can be enticed into force-intensive brushing through a commitment to dental health that is in itself to be welcomed and that damage is set at a significantly higher rate compared to the same age groups decades ago . These new toothbrushes therefore serve an etiological purpose oriented and therefore successful dentistry, save the patient expensive operations to cover exposed tooth necks with dubious long-term success and help to reduce costs.

Fig. 1

eine Handzahnbürste,

Fig. 2

eine Aufsteckbürste für einen vorzugsweise elektromechanischen Antrieb,

Fig. 3 bis 5

verschiedene mögliche Profilquerschnitte des Bürstenschaftes gemäß Schnittlinie III - III bei jedem der beiden Ausführungsbeispiel von Fig. 1 und 2,

Fig. 6 bis 8

ein weiteres, gegenüber den Ausführungsbeispielen von Fig. 1 und 2 abgewandeltes Ausführungsbeispiel einer Handzahnbürste, die aber auch für eine entsprechende Aufsteckbürste geeignet ist, mit zwei nacheinander ansprechenden "Knackpunkten", wobei

Fig. 6

die Zahnbürste in einer ersten Ausgangsstellung,

Fig. 7

die Zahnbürste in einer zweiten Mittelstellung und

Fig. 8

die Zahnbürste in einer dritten Endstellung zeigen.

Preferred embodiments of the invention are shown schematically in the drawing. Show it

Fig. 1

a manual toothbrush,

Fig. 2

a brush head for a preferably electromechanical drive,

3 to 5

different possible profile cross sections of the brush shaft according to section line III - III in each of the two exemplary embodiments of FIGS. 1 and 2,

6 to 8

another, modified from the embodiments of FIGS. 1 and 2 embodiment of a manual toothbrush, but which is also suitable for a corresponding brush head, with two successive "sticking points", wherein

Fig. 6

the toothbrush in a first starting position,

Fig. 7

the toothbrush in a second middle position and

Fig. 8

show the toothbrush in a third end position.

In the two exemplary embodiments of a manual toothbrush and a push-on brush for a preferably electromechanical drive shown in FIGS. 1 and 2, the brush shaft 1 in a deflection section 2 following the brush head 3 is in each case similar over part of its length to a leaf spring according to the crack frog principle formed that an optimal or maximum contact pressure can not be exceeded when brushing teeth until the brush head 3 is deflected. The brush head 3 is arranged on the brush shaft 1 so that it is suddenly deflected when a certain contact pressure is reached so that an optimal contact pressure can be maintained during brushing. The mechanical deflection or the audible exceeding of the sticking point in the deflecting section 2 of the brush shaft 1 designed according to the click frog principle thus provides an acoustic and / or tactile display when the optimum contact pressure on the brush shaft is reached.

Various examples of suitable deflection profiles 4 on the brush shaft 1 are shown in FIGS. 3 to 5, in each case in accordance with the section lines III-III of FIGS. 1 and 2. Thus, FIG. 3 shows a deflection profile 4 which is curved approximately in the shape of an arc in the transverse direction to its longitudinal extent Transition area between brush head 3 and brush shaft 1.

In the embodiment of FIG. 4, two profile strips 4a, 4b running in the longitudinal direction of the brush shaft 1 are angled relative to one another approximately in accordance with the curvature of the deflection profile 4 of FIG. 3 and are advantageously separated from one another in this way by a central longitudinal slot 4c, that when the contact pressure is exceeded, as well as the curved deflection profile 4 of FIG. 3, they come into a common stretched position transversely to the longitudinal extent of the brush shaft 1, so that the brush head 3, as indicated in FIGS. 1 and 2 by dash-dotted lines, comes from its previously stretched position can reach a deflection or kinking position 5 which is angled upwards with respect to the longitudinal axis of the brush shaft, in which the brush head 3 assumes an essentially unstable position and no longer allows teeth brushing.

The third exemplary embodiment shown in FIG. 5 for the deflection profile 4 between the brush shaft 1 and the brush head 3 has a corrugated shape transversely to the longitudinal extension of the brush shaft 1, but functions practically in the same way as that described above in connection with the two exemplary embodiments of FIGS. 3 and 4 has been set out. In all three exemplary embodiments shown, the thickness of the material cross-section and the curvature or the inclination of the legs 4a, 4b of the deflection profile 4 play an important role for determining the optimal or maximum contact pressure, but can be selected and shaped as required. Brush shaft 1, brush head 3 and deflection section 2 can each be formed in one piece from a suitable plastic or composite material with corresponding suspension properties.

In the modified exemplary embodiment shown in FIGS. 6 to 8, for example two different profile cross sections 4 corresponding to FIGS. 3 and 4 or 5 can be connected in succession such that the brush head 3 in relation to the brush shaft 1 in the pressure-relieved initial position of FIG. 6 is angled below in order to use a sufficient optimal contact pressure to reach the extended intermediate position shown in FIG. 7 after overcoming a first sticking point and, if this optimal contact pressure is exceeded after overcoming a second sticking point, to bend upward into the third deflection position shown in FIG. 8, in which the brush head 3 relative to the longitudinal axis of the brush shaft 1 is angled upward similarly to the two exemplary embodiments of FIGS. 1 and 2 and is in an unstable position in which brushing teeth is no longer possible.

Claims (5)

1. Toothbrush for manual or mechanical operation, of which the brush head is connected to the brush stem via a deflection portion allowing deflection of the brush head with respect to the brush stem under a predetermined contact pressure, characterised in that the deflection portion (2,4) has a profile cross-section which is designed such that it allows a sudden deflection of the brush head by the click principle once the predetermined contact pressure has been reached.
2. Toothbrush according to Claim 1, characterised in that the deflection portion (2,4) is curved in cross section substantially in an arc shape (Figure 3).
3. Toothbrush according to Claim 1, characterised in that the deflection portion is formed from two profile portions (4a, 4b) which extend in the longitudinal direction of the brush stem (1) and are angled from one another transversely to the longitudinal direction of the deflection portion substantially along an arcuate curvature of the deflection portion (4) (Figure 4).
4. Toothbrush according to Claim 1, characterised in that the deflection portion (4) is undulating in cross section (Figure 5).
5. Toothbrush according to one of Claims 1 to 4, characterised in that a plurality of deflection portions which yield under different contact pressures is provided between the brush head and the brush stem.

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