AU720929B2

AU720929B2 - Dental care apparatus and method for producing cleaning elements for said apparatus

Info

Publication number: AU720929B2
Application number: AU54806/98A
Authority: AU
Inventors: Georg Weihrauch
Original assignee: Pedex GmbH
Current assignee: Pedex GmbH
Priority date: 1996-11-12
Filing date: 1997-11-11
Publication date: 2000-06-15
Anticipated expiration: 2017-11-11
Also published as: TW492851B; ATE200194T1; UA52706C2; CA2271027A1; BR9713501A; EG22069A; DE19646519A1; AU5480698A; ID19093A; WO1998020774A1; PL333269A1; TR199901041T2; AR009607A1; NO992324D0; HUP9904245A2; EP0951225A1; KR100503216B1; NO992324L; DE59703319D1; CZ161799A3

Description

V.

PCT/EP97/06239 Translation of pages 1-7 and claims 1-14 submitted November 11, 1998 TOOTHBRUSH AND METHOD FOR THE MANUFACTURE OF BRISTLES FOR TOOTH BRUSHES The invention relates to a toothbrush with bristles made from an extruded polymer containing, at least in a region proximate the surface, a water or saliva soluble additive having dental medical effects as well as a method for the manufacture of such bristles for a toothbrush.

Known toothbrushes have exclusively a mechanical cleaning action by friction between the bristles and the tooth surface. They also have a massaging effect on the gingiva.

Bristles have also been proposed with which the polymer contains metallic ions having an antibacterial effect e.g. in the form of Zeolite (Derwent abstract 91-004868/01 of JP 02- 283312A) or soluble organic additive having anti-microbe O effects (Derwent abstract 94-217929/26 of WO 94/13870A) The problem of the invention is to extend the sphere of action of known toothbrushes.

According to the invention this problem is solved in that inorganic fluorine compounds, which separate fluoride in response to water and/or saliva, are incorporated into the polymer in solid, finely dispersed form.

The use of additives in the form of fluorine compounds with a dental action is known inthe case of liquid and paste-type dentifrices in order to utilize the tooth-hardening action of Sfluoride compounds. The action is based on the fact that human dental enamel has in its outermost coating a relatively high fluoride concentration, which rapidly decreases in the tooth depth. The fluoride quantity supplied with food and drinking water is generally not sufficient to keep stable the fluoride content in the dental enamel. In addition, the fluoride content is decisive for the resistance of the teeth to the attack of bacteria and acids, which once again lead to the most frequent dental disease, namely caries. The action mechanism of such fluorides is based on the ions of easily sbluble fluorides which form on the tooth surface a calcium fluoride (CaF 2 coating, from which fluoride is released on changing the pH-value in the saliva, without depleting the fluoride reservoir of the dental enamel. The antibacterial action of such fluorides has also already been described and probably reduces the acid production of bacteria in the plaque. Such additives are usually in dissolved form in dentifrices.

In the toothbrush constructed according to the present Sinvention additives are incorporated in solid, finely dispersed form into the polymer bristles. The additives are soluble in water and/or saliva. The ultra-fine particles more particularly embedded in the surface-near region of the cleaning element form a type of reservoir from which the active substance is slowly dissolved out and is delivered to the oropharynx, particularly in the vicinity of the denture.

The normally used polymers to a certain extent absorb moisture, which advances into the interior of the bristles or migrates out on drying after use. As a result of the physical processes, with time the additives migrate out of the core of the cleaning element to the surface from where they evolve their action.

Possible inorganic fluoride separating fluorine compounds are chosen from the group comprising sodium fluoride (NaF), sodium monofluorophosphate (Na 2

PO

3 zinc fluoride (ZnF 2 and ammonium fluoride (NH 4 F) and fluorosilicates.

The fluoride compounds embedded in the polymer and in particular exposed on the surface, during the use of the dentifrice and in conjunction with saliva or the water used for cleaning purposes, form a slowly flowing fluoride source, O which constantly supplements the natural fluoride reservoir of the dental enamel, optionally in conjunction with the correspondingly doped dentifrices.

Into the polymer of the bristles can be incorporated in disperse form further inert, insoluble additives for increasing the mechanical cleaning action. This measure is known per se in connection with bristles for toothbrushes in order to bring about a certain abrasive action. In conjunction with the additives according to the invention, dO such purely mechanically acting additives must be inert. They must in particular not be surface-active and must also not enlarge their surface during use. These finely dispersed, abrasive particles are washed out in time when using the toothbrush. Thus, on the bristles are exposed new surfaces 2aS and therefore dental active fluorine compounds.

In order to ensure effective action of the additives, it is recommended that the bristles have for the enlargement of their surface a shape diverging from the stretched, smooth 1O shape, e.g. are profiled, corrugated or spirally wound.

Instead of this, the bristles can be flocked and also the flock fibers filled with additives.

Another advantageous embodiment is characterized in that the bristles comprise a core and a jacket which are co-extruded, wherein the additives are incorporated into the jacket.

6In this construction the core can in particular be formed from a polymer giving the cleaning element the necessary use characteristics such as tensile strength, bending capacity and resistance to alternate flexing (recovery capacity), whereas the polymer for the jacket is chosen mainly with a 1O view to the embedding of the additives and their successive delivery.

In conjunction with the invention it is advantageous to use those toothbrushes, which are equipped with replaceable bristles, i.e. so-called change head brushes. As it is advantageous to frequently change the toothbrush or replace such change heads due to bristle wear and the decreasing cleaning action or increasing risk to the gingiva, the regular replacement of the bristles filled according to the d0 invention acquires even greater significance. Particular advantage is obtained with brushes having closely juxtaposed individual bristles, whereof up to 2000 can be housed on the surface of a conventional toothbrush head.

d 5 The invention also relates to a method for the manufacture of the above mentioned polymer bristles for toothbrushes by the extrusion of the polymer from a melt into which are admixed inorganic fluorine compounds separating fluoride which are soluble in water and/or saliva in finely dispersed form.

Practical tests have shown that in particular the fluoridesplitting off fluorine compounds known for their dental ation and which are present in crystalline or amorphous form as<,alts or hydrofluoric acid, are not chemically and physically impaired on admixing to a polymer melt, i.e. are sufficiently thermally stable, and in the extruded, cured polymer are present in unchanged form. A finely dispersed distribution of the additives can be achieved in the same way B as in all other solids, which are processed in finely dispersed form in polymers, e.g. dye pigments, etc..

The additives are preferably chosen from the group sodium fluoride (NaF), sodium monofluorophosphate (Na 2

PO

3 zinc 10 fluoride (ZnF 2 ammonium fluoride (NH 4 F) and fluorosilicates.

The additives are preferably added to the melt in a quantity of 1500 to 4500 ppm. The exact proportion is dependent on the nature of the fluorine compound and its reaction in the polymer surface during use of the toothbrush.

Preferably to the polymer melt are admixed inert, insoluble additives for increasing the mechanical cleaning action, .0 which are slowly washed out during the use of the toothbrush and expose new, free surfaces with dental active additives.

The polymers used for the bristles are chosen from the group of polyamides, polyolefins, polyesters, polyacetals, sulfur polymers and their copolymers.

For forming two-component bristles of a core and a jacket, the additives are admixed to the polymer melt for the jacket.

Claims

2. Toothbrush according to claim i, characterized in that the additives are chosen from the group comprising sodium fluoride (NaF), sodium monofluorophosphate (Na 2 PO 3 F), zinc fluoride (ZnF2), ammonium fluoride (NH 4 F) and fluorosilicates.
3. Toothbrush according to claim 1 or 2, characterized in that the bristles contains further inert, insoluble additives in dispersed form for increasing the mechanical 2o cleaning action.
4. Toothbrush according to one of the claims 1 to 3, characterized in that for increasing the surface area of the bristles, they have a shape diverging from the 2- stretched form, e.g. are profiled, corrugated or spirally wound. Toothbrush according to any one of the claims 1 to 4, characterized in that the bristles are flocked and also O the flock fibers are filled with additives.
6. Toothbrush according to any one of the claims 1 to 7 Tcharacterized in that the bristles comprise a core and a 7 jacket, which are co-extruded, and the additives are incorporated into the jacket.
7. Toothbrush according to one of the claims 1 to 6, characterized in that the toothbrush is provided with replaceable bristles.
8. Toothbrush according to claim 7, characterized in that the toothbrush is provided with a replaceable bristle facing.
9. Method for the manufacture of bristles made from a polymer for toothbrushes by extruding the polymer from a melt to which are mixed additives soluble in water and/or saliva having a dental action, characterized in that inorganic fluoride separating fluorine compounds in finely dispersed form are admixed as additives. Method according to claim 9, characterized in that 1500 A O to 4500 ppm of additives are added to the polymer melt.
11. Method according to-claim 9 or 10, characterized in that the additives are chosen from the group sodium fluoride (NaF), sodium monofluorophosphate (Na 2 PO 3 zinc S fluoride (ZnF 2 ammonium fluoride (NH 4 F) and fluorosilicates.
12. Method according to one of the claims 9 to 11, characterized in that with the polymer melt are admixed inert, insoluble additives for increasing the mechanical cleaning action. -S T Method according to one of the claims 9 to 12, characterized in that the polymer is chosen from the z 8 group of polyamides, polyolefins, polyesters, polyacetals, sulfur polymers and their copolymers.
14. Method according to one of the claims 9 to 13, characterized in that for forming two-component bristles with a core and a jacket, the additives are admixed to the polymer melt for the jacket.