WO2004110297A1 - Removable denture - Google Patents

Abstract

The invention relates to removable dentures provided with spring means for pressing the dentures onto the jaw in the mouth of a wearer, wherein the spring means comprise at least one spring element that is attached to the outside at the buccal side of the dentures.

Description

REMOVABLE DENTURE

The invention relates to removable dentures provided with spring means for pressing the dentures onto the jaw in the wearer's mouth.

Proper abutment of the dentures on the jaw in the wearer's mouth is a known problem. Many wearers have problems with loose dentures. Loose dentures may result in speech problems. In addition pressure locations may arise resulting in bone reduction or osteo nerosis especially in the mandible or lower jaw, because of which the dentures will get even more loose.

It is therefore common practice to provide dentures with adhesive paste. Such adhesive pastes have a lot of drawbacks. For instance under the influence of certain foodstuffs dentures may come loose nonetheless. In addition dentures are more difficult to clean, adhesive pastes affect the taste and some people may be or become allergic to them. Moreover the adhesive paste has to be applied again and again, which costs money every time.

Another solution is fixing the dentures in the jawbone by means of implants. However, implants are expensive, difficult to place, and the lifespan often is uncertain. In addition implants are unsuitable for older patients, diabetics and other patients that cannot be operated on. In addition placing implants is burdensome on a patient.

From FR-A-2.177.167 a solution is known in which springs are attached at the dorsal side of the dentures. The springs therefore extend beyond the rear or dorsal side of the dentures into the oral cavity. From EP-A1 -266.962 a complete set of dentures is known having helical springs mounted as bending spring with the lead screw parallel to the buccal side. In addition a complete set of dentures is described provided with wire springs which for a large part are accommodated in accommodation spaced in the denture parts. Said wire springs furthermore extend beyond the dorsal side of the dentures in the oral cavity.

The springy action of the spring elements is not optimal in the known dentures. Moreover food residues may accumulate between the spring element and the dentures. In addition the wearer may be hindered by the spring elements because they extend beyond the dentures into the oral cavity. In addition the chewing motions are often hindered.

It is an object of the invention to at least partially overcome the said drawbacks.

It is a further object of the invention to offer dentures provided with spring means that press a lower and upper set of dentures apart against the jaws with a sufficient yet light pressure. Preferably the spring means are compact and almost maintenance free. It is a further object to offer spring means that are easy to clean.

It is a further object to offer spring means with which the chewing motions, sideward and forward and backward, can be carried out without problems. Spring systems used earlier on had the drawback of being too bulky and difficult to clean, for instance because a small coiled spring was placed in a more or less closed off housing. On the other hand skin of the denture wearer's cheek might get wedged between the windings of the spring.

Other drawbacks were the recurring breaking of the little spring and the limitations of the chewing motion. The invention provides removable dentures provided with spring means for pressing the dentures onto the jaw in the mouth of a wearer, wherein the spring means comprise at least one spring element that is attached to the outside at the buccal side of the dentures, wherein the spring element comprises a wire spring having a winding that is substantially parallel to the buccal plane.

Thus dentures can be realised which have a better abutment to the jaw than known dentures. Moreover the placement of the spring element offers the possibility to realise dentures wherein a chewing motion can be carried out almost unhindered, and food residues between the spring element and further denture parts are easy to remove because the spring elements have been arranged adjacent, preferably freely adjacent, to the dentures. In addition a highly durable spring element can be designed.

In an embodiment the dentures have a rear side extending farthest into the mouth, that means the dorsal side, wherein the spring element extends substantially in front of or mesial to the dorsal side.

In an embodiment the spring element is positioned between the dorsal side and the canine tooth.

In an embodiment the dentures extend labially beyond the spring means. In these embodiments the spring elements do not extend beyond the dentures. Thus the wearer is hardly hindered by the spring elements. Also because of the embodiments described below, such a spring element can be realised.

In an embodiment the spring means are attached either on or in the artificial resin basis of the dentures. Preferably the spring elements freely abut the buccal side. In an embodiment the spring means comprise a wire of resilient material, preferably metal or synthetic material, preferably an alloy comprising nickel- titanium.

In a further embodiment the spring means comprise a cylindrical helical spring as rotation spring, substantially parallel to the buccal plane.

In an embodiment the rotation spring in relaxed condition has one circumferential winding. Thus a spring element can be realised that can be kept compact so that it hinders the wearer of the dentures as little as possible. In addition it offers the creator sufficient freedom to adapt the design to the specific wearer and dentures. Furthermore adaptations can easily be made to this shape for realising specific spring properties.

In an embodiment the wire comprises a first and second end, wherein the wire is attached to the dentures with the first and second end. In an embodiment thereof the spring element is a rotation spring which in the relaxed condition has one circumferential winding and one end passed through the winding. In fact an overhand or half knot is thus created. This specific shape appeared to offer the possibility of adapting the resilient properties of the spring element very well to the requirements of use. Moreover the spring element could be kept compact.

In an embodiment the wire is bent in a shape with at least one crossing wherein the wire crosses itself at least once. In a special embodiment the wire has three crossings. It has appeared that these crossings offer possibilities to further optimize the spring properties for this purpose.

In an embodiment the wire of flexible material comprises a knot that has not been pulled, preferably an overhand knot or half knot. It thus appeared possible to adapt spring properties to the specific requirements for use for dentures. For instance it appeared possible by means of adaptations to create an adjustable hysteresis. Moreover it appeared possible to adapt the spring properties adjustably. In addition the spring element could be designed compact.

In an embodiment the spring element comprises a ring around at least one crossing. As a result the spring characteristic can be adjusted as desired. Moreover it is prevented that due to jaw movement room is created between the crossing parts, in which the skin of the cheek may get stuck.

In an embodiment the spring element comprises a ring around each crossing. Thus the spring characteristic can be accurately set. Moreover it is prevented that skin from the inside of the cheek may get stuck between the crossing parts.

In an embodiment the spring element comprises a stop for the ring on the wire beyond a crossing, preferably between two crossings. Thus it is prevented that the ring moves away from the crossing.

In an embodiment the stop is a fitting ring on the wire. Such a stop ring may be slid onto the wire and optionally be glued onto it.

In an embodiment the spring means comprise a first and second attachment member, wherein the first and second attachment member are arranged at the dentures between the dorsal side and the canine tooth, at the buccal side of the dentures.

In an embodiment the attachment members are disposed either on or in the artificial resin, that means the basis, of the dentures. In practice said synthetic part usually is the pink part of the dentures. As a result the spring elements are easy to dispose without damaging the dentures, even on already existing dentures. In an embodiment the spring means do not extend beyond the labial side, preferably not beyond the canine teeth.

In an embodiment the dentures comprise a mandibular or lower jaw part and a maxillary or upper jaw part, wherein the spring means comprise a first and second attachment member, and wherein the first attachment member is connected to the lower jaw part and the second attachment member is connected to the upper jaw part.

In an embodiment the dentures comprise at least a first denture part forming an almost complete arch wherein the spring means comprise at least two spring elements at opposite buccal sides of the first denture part.

In an embodiment the dentures are a complete set of dentures having lower dentures forming an almost complete arch and upper dentures forming an almost complete arch, wherein spring means comprise a first and second spring element, wherein the spring elements comprise a first and second attachment member, wherein the first spring element with its first attachment members at the buccal side is attached on or in the basis of the upper dentures between the dorsal side and the canine tooth and with its second attachment members at the buccal side is attached on or in the basis of the lower dentures between the dorsal side and the canine tooth, and the second spring element with its first attachment members at the opposite buccal side is attached on or in the basis of the upper dentures between the dorsal side and the canine tooth and with its second attachment members at the opposite buccal side is attached on or in the basis of the lower dentures between the dorsal side and the canine tooth.

In an embodiment the spring means are pre-biassed for, when placed in the mouth of a wearer, exerting a force onto the dentures, which force presses the dentures onto the jaw of the wearer. In an embodiment of the dentures the spring means comprise the first and second attachment member, wherein the spring means are substantially situated in a plane and at least one attachment member is situated out of the plane.

In an embodiment the spring means abut the buccal side of the dentures in a springy manner.

In an embodiment the spring means comprise at least one spring element comprising a wire of resilient, flexible material of which the ends form first and second attachment members for connecting the spring element with the dentures, wherein at least one of the attachment members is pre-biased towards the dentures. As a result the spring element in the attached condition will resiliently abut the dentures. Thus comfort of wearing is increased.

In an embodiment both attachment members are pre-biased towards the dentures. As a result the spring element abuts the dentures. Moreover the lower and upper set of dentures are placed stably with respect to each other.

In an embodiment, considered from the dorsal side, the spring element is bent in an arc of a circle, which is substantially parallel to the buccal plane when the dentures are placed in the mouth of a wearer.

In an embodiment wherein the spring means comprise the first and second attachment member, the attachment members at the level of the canine teeth are connected to the basis of the dentures and the spring means extend along the buccal side in the direction of the dorsal side.

In an embodiment the dentures comprise at least one lower set of dentures and at least one upper set of dentures, and the spring elements connect the lower and upper set of dentures to each other. In an embodiment the spring elements exert a force pushing the upper and lower set of dentures apart when the lower and upper set of dentures are brought against each other.

In an embodiment the spring means comprise a spring element having two arms that are connected one to the other, and at the ends are provided with attachment members.

In an embodiment the longitudinal axes of both arms cross each other in the relaxed condition of the spring element.

In an embodiment both arms are pre-biased for pushing the spring element against the buccal side of the dentures.

In an embodiment the spring means comprise a spring element having two resilient arms that are connected one to the other, wherein the arms are resiliently movable towards and away from each other, and wherein the spring element further comprises a guide for guiding the arms.

In an embodiment the guide is formed for giving a hysteresis between the motion towards and away from each other of the arms.

In an embodiment the guide guides the arms along a path that deviates from the connecting line of the ends of both arms.

In an embodiment the spring element is furthermore provided with means for keeping the arms along the guide during the springy motion.

In an embodiment the spring element comprises a wire element provided with at least one winding substantially parallel to the buccal plane. In an embodiment the spring element comprises a wire of resilient material which is tied under pre-bias, such that friction arises on the crossings and a hysteresis effect is achieved.

In an embodiment the spring element comprises a wire of resilient material, wherein the wire comprises at least one loop and at one or several locations is provided with sliding rings and/or friction rings, optionally supplemented with stop rings for the sliding rings or friction rings. The stop rings may be glued.

In an embodiment the wire is tied the other way round as a result of which it can be adapted better to a broader lower jaw.

In an embodiment the spring element comprises a wire of resilient material having at least one loop with two ends extending from the loop like two arms, and the loop of the spring at the location along which the arm slides, and the loop between the arms is programmed inclined or with a curve to adapt the spring character.

In an embodiment the ends of the arms comprise attachment means for attachment of the arms to the denture parts.

In an embodiment the ends of the arms comprises attachment members, preferably an eye, which attachment member is brought out of the axis of the arm.

In an embodiment for manufacturing dentures as described above, the spring means comprise first and second attachment members, wherein the method comprises the step of fixing the spring elements on the lateral sides of the dentures by means of attachment elements.

In an embodiment of the method holes are made in a (pink) synthetic resin part of the dentures, and attachment elements provided with spring means are arranged in the holes.

The invention further relates to a method for manufacturing dentures as described above, wherein the spring means comprise first and second attachment members, wherein the method comprises the step of casting the attachment members in a (pink) synthetic resin basis of the dentures.

The invention further relates to resilient members suitable as spring elements for dentures as described above.

The invention further relates to dentures, comprising a lower set of dentures and an upper set of dentures, connected to each other by means of spring elements, wherein the spring elements comprise at least one cylindrical helical spring as rotation spring having one winding in the relaxed condition with one end guided back through the winding, and arranged substantially parallel to the buccal plane adjacent to the dentures.

Such a rotation spring arranged in the described manner turns out to result in the least hindrance to the wearer, whereas the spring action can easily be optimised.

In an embodiment the rotation spring has at least one crossing of a wire of the rotation spring, wherein the rotation spring on the crossing is provided with means for slidably keeping the wire onto each other at the location of the crossing, preferably a flexible synthetic ring. Thus it is prevented that during use the wires may move apart at the location of the crossing. When the wires move apart the skin of the cheek may get wedged between the wires.

In a further embodiment thereof the rotation spring is furthermore provided with a stop for keeping the means for slidably keeping onto each other at the crossing, wherein the stop preferably is a thickening arranged on the wire of the rotation spring, preferably a ring arranged on the wire. Displacement is thus prevented.

An embodiment of the spring element regards a wire spring of extremely elastic material constructed in a loop. The material may consist of body- friendly metal or synthetic material.

For the prototypes a special nickel-titanium alloy with some other additions was started from. As the overall construction largely consists of a thin resilient wire it takes up very little space.

In an embodiment the spring element is attached in or on the dentures by means of two attachment buttons. The portion of the buttons extending beyond the dentures preferably has a diameter of only 1 .5mm x 5mm.

Due to the special shape and because they are mounted in a loop with a half reef knot, the spring elements cannot turn over when they are compressed. In this way it also prevented that the springs may end up between the elements (teeth and molars). The shape of the spring is such that it is no impediment to the jaw motions. Considered from above the spring is bent along with the radius in which the elements have been placed. The relatively large loop contributes to the material not being loaded too much. The spring arms are rotatably attached to the dentures.

The length of the spring arms can be adjusted to the situation of the dentures. Particularly partial dentures may need large adaptations. In special cases strongly deviating springs can be produced. It is also possible to make another attachment at the end of the arms. This includes the following options: an eye according to the prototype, either with or without a closed eye. An eye that is positioned further away from the centre of the spring arm. An eye in the centre of the spring arm. A hook-like construction. A straight end that is clamped into an accommodation system.

It may happen to a group of patients that the skin of the cheek may get wedged between the spring at the location where the spring crosses. This has been dealt with satisfactorily by placing a small ring over the crossing. As a result not too much space may arise between the crossed spring wires so that this problem can no longer occur. In crossings that slide during the spring stroke the small ring has to be able to slide along with the crossing. In order to prevent that the small ring may slide too far or, in case of a spring that has been mounted the other way round, slide down, it may be necessary to arrange a stop or blocking device. In the prototypes, use was made of a small ring that had been slid over one single wire and had been glued at the correct location and/or could slide along, but getting stuck on the next first crossing.

The first prototypes were made in tied condition in the mould using a well- programmed nickel-titanium alloy. Considerable improvements however, were achieved with less tough alloys that may be less well-programmable yet due to an adapted programming method still gave a better result. To that end the springs are not programmed in tied condition, but indeed with some distance between the windings. After tying, the crossings of the windings will abut tightly, see the drawings. The resulting friction is an important increase in hysteresis between the ingoing motion and the outgoing motion

The hysteresis can for an important part be defined by varying the preprogrammed distance between the windings. As a result the pre-bias on the wire crossings of the spring is defined after tying. By not passing one, several or all crossings to the other side (so by not tying) and providing sliding rings, the hysteresis effect may be lowered further. If the sliding rings are replaced by a material having larger friction and preferably having an elastic character, and are placed slightly tight around one or several crossings, the hysteresis effect can be further increased. It should be ensured that the dentures also properly abut when opening the jaws. The spring character can also be adapted by making the loop slightly inclined at the location along which the arm slides. A curve may if so desired result in a further adaptation. For instance for adapting a certain relax position.

The hysteresis ensures that during biting the pressure force becomes considerably larger than during opening the jaws. As a result a comfortable relax situation is achieved, bone resorption is prevented as much as possible and a proper jaw and biting function is achieved.

By tying the spring the other way round it may be better adaptable to a lower jaw that is broader than the upper jaw. Usually this requires placing the sliding ring and the stop ring at the upper side.

The spring systems described can also be used for patients having partial dentures or even only having a lower or upper set of dentures. For particular situations, systems can be made having an asymmetrical spring character. Sometimes one single spring may be the solution, for instance in case of temporary provisions after surgery.

A part of the dentures may even consist of a plate or frame without elements, that means without teeth or molars.

It is also possible to make the eyes of the spring elements larger or smaller, or to adapt the dimensions of the ties, as a result of which the spring elements if so desired can either be removed from the dentures, so that the dentures can also be worn without the spring elements, or be permanently connected to the dentures.

The invention will be elucidated on the basis of an exemplary embodiment of dentures according to the invention, in which: Figure 1 shows removable dentures provided with spring means;

Figure 2 shows an embodiment of spring means according to the invention;

Figure 3 shows an alternative embodiment of the spring means;

Figure 4 shows another alternative embodiment of the spring means;

Figure 5 shows a further development of the spring means according to the invention;

Figure 6 shows a side view of an embodiment of the spring means according to the invention;

Figure 7 shows a front view of the spring means of figure 6;

Figure 8 shows an embodiment of the spring means a ring around a crossing and stop;

Figure 9 shows a view in perspective of the spring means of figure 7 in pre- biased condition;

Figure 10 shows a further view in perspective of the spring means of figure 7; and

Figure 1 1 shows a side view of the spring means of figure 7 further provided with guides.

Figure 1 shows removable dentures 1 provided with a wire 4 wound into a spring for pressing the removable dentures onto the jaw. A full set of dentures provided with a lower element O and an upper element B is shown here. Both the upper element B and the lower element O have been provided with a basis of pink artificial resin 3 in which the teeth or molars ("elements") 2 have been placed. A spring element 4 is connected to the (usually pink) artificial resin part 3. Said spring element 4 comprises arms 6 and 6' that are connected one to the other, and both at the ends provided with attachment members 5' and 5.

The spring element 4 is attached in the pink artificial resin part 3 by means of the attachment members 5' and 5 with a button. The spring is then pre- biased for exerting a force that pushes both sets of dentures B and O apart. In many cases a spring element 4 will be attached on both buccal sides of the arch.

The spring means 4 shown here comprise a wire in which a winding has been arranged. The embodiments of the spring means 4 will be further discussed.

Figure 2 shows a first embodiment of the spring means 4, in this case a coiled wire having a winding 10, wherein both ends of the wire 6 and 6' form the arms 6 and 6', respectively, of the spring element 4 as described above. Both ends of the wire have been folded into eyes 5, 5' with which the spring element can be attached to dentures as discussed above in figure 1 .

In practice, a spring element 4, as shown in figure 1 , will be attached at both buccal sides of the dentures as shown in figure 1 . The attachment members will then be arranged at the level or just behind the position of the canine tooth and the spring element extends to the rear, just in front of or mesial to the dorsal side of the teeth a depicted here. As a result the spring element will not or hardly be visible when worn, and a user will hardly be hindered by it. Figure 3 shows an alternative embodiment of the spring element 4, wherein the wire of resilient or springy material has been wound in a more or less triangular winding 10. An advantage of this embodiment is that the winding in the direction of the dorsal side takes up less space and as a result in case of certain jaw shapes will be less troublesome to a patient.

Figure 4 shows an embodiment of the spring element according to the invention, wherein the wire has this time been tied into a so-called overhand or half knot. As a result the wires cross each other properly on the crossings, and there is less risk of for instance the skin of the cheek getting wedged between the spring elements.

Figure 5 shows an embodiment of the spring means 4, wherein a flexible wire has been wound or folded as for instance shown in figures 2 or 4, wherein in order to ensure that no cheek parts get wedged between the spring, rings have been arranged around both wires on the crossings

(indicated by 7, 7' and 7" in figure 4) so that the wires remain crossing over each other when the arms 6 and 6' move towards and away from each other.

Figure 6 shows an embodiment of the spring element 4, in this case a coiled wire, wherein the wire is not tied but folded in a winding 10. Figure 6 shows the spring element in relaxed condition and in side view.

Figure 7 shows the spring element of figure 6 in front view, that means seen from the labial side of the teeth towards the dorsal side. In this figure it can clearly be seen how both arms 6 and 6' with respect to the straight dotted line are pre-biased in the direction B, in direction of the cheek when the dentures are placed. When the spring element 4 has been arranged on the dentures, this results in a force that presses the spring element against the dentures. Figure 8 again shows the spring element 4 of figure 6 and 7, this time provided with a ring 8 around one of the crossings and a stop 9. The ring 8 among others serves to prevent that too much space arises between the wires at the level of the crossing as a result of which the cheek of the wearer might get in between both wires. The direction A-A' is also shown in this figure on which the wires are pre-biased before arranging spring element 4 on the dentures. Because of this pre-bias both parts of the dentures are moved apart.

Figure 9 shows the spring element of figure 8 in a slightly different perspective as a result of which it can clearly be seen how the arms are bent and the ring 8 has been arranged around both wires on the crossing in order to prevent that too much play arises between the wires. Stop 9 has been arranged in order to prevent that in the reciprocal motion of the arms 6, 6' the ring 8 moves to another crossing.

Figure 10 shows a view in perspective of the spring element of among others figures 8 and 9, wherein in this figure it can clearly be seen how both arms 6 and 6' are pre-biased as described in figure 7.

Figure 1 1 shows a further embodiment of a spring element 4 according to the invention, wherein again a tied flexible wire is used which is tied in the shape of an overhand knot 10. Again the ring 8 and stop 10 have been arranged as described above. Moreover side 1 1 of the winding in this embodiment serves as guide 1 1 for the arms 6 and 6' in the following manner. When the guide 1 1 in front view forms a straight line, when forces are exerted on both ends of the arms as indicated with the force lines and forces F, the ends will move towards and away from each other with hardly any hysteresis in this motion. By arranging a curve, considered in front view, on the piece of wire forming the guide 1 1 , as shown in figure 1 1 , the wires through the guides no longer follow the way along dotted line L connecting both arms 6 and 6', but the force will be active along the force lines M and M'. This results in a hysteresis, as a result of which the force when bringing the arms towards each other will be larger than the force when moving the arms apart. It turned out that this makes increased comfort of wearing possible as well as a better fixing of the dentures onto the jaw.

It will be clear that the above description is given for illustrating the operation of preferred embodiments of the invention, and not for limiting the scope of the invention. The scope of the invention will only be limited by the claims below. Starting from the above elucidation may variations that fall within the spirit and scope of the present invention will be evident to a man skilled in the art.

Claims

Claims

1 . Removable dentures provided with spring means for pressing the dentures onto the jaw in the mouth of a wearer, wherein the spring means comprise at least one spring element that is attached to the outside at the buccal side of the dentures, wherein the spring element comprises a wire spring having a winding that is substantially parallel to the buccal plane.

2. Dentures according to claim 1 , characterized in that the spring element extends in front of the dorsal side of the dentures.

3. Dentures according to claim 1 or 2, wherein the spring element is positioned between the dorsal side and the canine tooth.

4. Dentures according to claim 1 , 2 or 3, wherein the dentures extend labially beyond the spring means.

5. Dentures according to any one of the preceding claims, wherein the dentures have a basis of synthetic material in which denture elements may be present, wherein the spring means are attached either on or in the artificial resin basis of the dentures.

6. Dentures according to any one of the preceding claims, wherein the spring means comprise a wire of resilient material, preferably metal or synthetic material, preferably an alloy comprising nickel-titanium.

7. Dentures according to claim 6, wherein the spring means comprise a cyiindrical helical spring as rotation spring, substantially parallel to the buccal plane.

8. Dentures according to claim 7, wherein the rotation spring in relaxed condition has one circumferential winding.

9. Dentures according to claims 6-8, wherein the wire comprises a first and second end, wherein the wire is attached to the dentures with the first and second end.

10. Dentures according to any one of the preceding claims 6-9, wherein the wire is bent in a shape with at least one crossing wherein the wire crosses itself at least once.

1 1 . Dentures according to claim 10, wherein the wire has three crossings.

12. Dentures according .to any one of the claims 7-1 1 , wherein the wire of flexible material comprises a knot that has not been pulled, preferably an overhand knot or half knot.

13. Dentures according to any one of the preceding claims 8-12, comprising a ring around at least one crossing.

14. Dentures according to any one of the preceding claims 8-12, comprising a ring around each crossing.

15. Dentures according to claim 13 or 14, comprising a stop for the ring on the wire beyond a crossing, preferably between two crossings.

16. Dentures according to claim 15, wherein the stop is a fitting ring on the wire.

17. Dentures according to any one of the preceding claims, wherein the spring means comprise a first and second attachment member, wherein the first and second attachment member are arranged at the dentures between the dorsal side and the canine tooth, at the buccal side of the dentures.

18. Dentures according to any one of the preceding claims, wherein the attachment members are disposed either on or in the pink artificial resin, that means the basis, of the dentures.

19. Dentures according to any one of the preceding claims, wherein the spring means do not extend beyond the labial side, preferably not beyond the canine teeth.

20. Dentures according to any one of the preceding claims, wherein the dentures comprise a lower jaw part and an upper jaw part, wherein the spring means comprise a first and second attachment member, and wherein the first attachment member is connected to the lower jaw part and the second attachment member is connected to the upper jaw part.

21 . Dentures according to any one of the preceding claims, comprising at least a first denture part forming an almost complete arch, wherein the spring means comprise at least two spring elements at opposite buccal sides of the first denture part.

22. Dentures according to claim 21 , wherein the dentures are a complete set of dentures having a lower element forming an almost complete arch and an upper element forming an almost complete arch, wherein spring means comprise a first and second spring element, wherein the spring elements comprise a first and second attachment member, wherein the first spring element with its first attachment members at the buccal side is attached on or in the basis of the upper element between the dorsal side and the canine tooth and with its second attachment members at the buccal side is attached on or in the basis of the lower element between the dorsal side and the canine tooth, and the second spring element with its first attachment members at the opposite buccal side is attached on or in the basis of the upper element between the dorsal side and the canine tooth and with its second attachment members at the opposite buccal side is attached on or in the basis of the lower element between the dorsal side and the canine tooth.

23. Dentures according to any one of the preceding claims, wherein the spring means are pre-biased for, when placed in the mouth of a wearer, exerting a force onto the dentures, which force presses the dentures onto the jaw of the wearer.

24. Dentures according to any one of the preceding claims, wherein the spring means comprise the first and second attachment member, wherein the spring means are substantially situated in a plane and at least one attachment member is situated out of the plane.

25. Dentures according to claim 22, wherein the spring means abut the buccal side of the dentures in a springy manner.

26. Dentures according to any one of the preceding claims, wherein the spring means comprise at least one spring element comprising a wire of resilient, flexible material of which the ends form first and second attachment members for connecting the spring element with the dentures, wherein at least one of the attachment members is pre-biased towards the dentures.

27. Dentures according to claim 26, wherein both attachment members are pre-biased towards the dentures.

28. Dentures according to claim 27, wherein considered from the dorsal side, the spring element is provided with an arc of a circle bent substantially parallel to the buccal plane when the dentures are placed in the mouth of a wearer.

29. Dentures according to any one of the preceding claims, wherein the spring means comprise the first and second attachment member, wherein the attachment members at the level of the canine teeth are connected to the basis of the dentures and the spring means extend along the buccal side in the direction of the dorsal side.

30. Dentures according to any one of the preceding claims, wherein the dentures comprise at least one lower set of dentures and at least one upper set of dentures, and the spring elements connect the lower and upper set of dentures to each other.

31 . Dentures according to claim 30, wherein the spring elements exert a force pushing the upper and lower set of dentures apart when the lower and upper set of dentures are brought against each other.

32. Dentures according to any one of the preceding claims, wherein the spring means comprise a spring element having two arms that are connected one to the other, and at the ends are provided with attachment members.

33. Dentures according to claim 32, wherein the longitudinal axes of both arms cross each other in the relaxed condition of the spring element.

34. Dentures according to claim 32 or 33, wherein both arms are pre-biased for pushing the spring element against the buccal side of the dentures.

35. Dentures according to any one of the preceding claims, wherein the spring means comprise a spring element having two resilient arms that are connected one to the other, wherein the arms are resiliently movable towards and away from each other, and wherein the spring element further comprises a guide for guiding the arms.

36. Dentures according to claim 35, wherein the guide is formed for giving a hysteresis between the motion towards and away from each other of the arms.

37. Dentures according to claim 36, wherein the guide guides the arms along a path that deviates from the connecting line of the ends of both arms in their initial position.

38. Dentures according to claim 35, wherein the spring element is furthermore provided with means for keeping the arms along the guide during the springy motion.

39. Dentures according to any one of the preceding claims, comprising a wire element provided with at least one winding parallel to the buccal plane.

40. Dentures according to any one of the preceding claims, wherein the spring element comprises a wire of resilient material which is tied under pre- bias, such that friction arises on the crossings and a hysteresis effect is achieved.

41 . Dentures according to any one of the preceding claims, wherein the spring element comprises a wire of resilient material, wherein the wire comprises at least one loop and at one or several locations is provided with sliding rings and/or friction rings, optionally supplemented with stop rings.

42. Dentures according to claim 41 , wherein the wire is tied the other way round as a result of which it can be adapted better to a broader lower jaw.

43. Dentures according to any one of the preceding claims, wherein the spring element comprises a wire of resilient material having at least one loop with two ends extending from the loop like two arms, and the loop between the arms is programmed inclined or with a curve to adapt the spring character.

44. Dentures according to claim 43, wherein the ends of the arms comprise attachment means for attachment of the arms to the denture parts.

45. Dentures according to claim 44, wherein the end of the arms comprises an attachment member, preferably an eye, which attachment member is brought out of the axis of the arm.

46. Method for manufacturing dentures according to any one of the preceding claims, wherein the spring means comprise first and second attachment members, wherein the method comprises the step of fixing the spring elements on or in the lateral sides of the dentures by means of attachment elements.

47. Method according to claim 46, wherein holes are made in a synthetic resin part of the dentures, and attachment elements provided with spring means are arranged in the holes.

48. Method for manufacturing dentures according to any one of the preceding claims 1 -45, wherein the spring means comprise first and second attachment members, wherein the method comprises the step of casting the attachment members in a synthetic resin basis of the dentures.

49. Dentures, comprising a lower set of dentures and an upper set of dentures, connected to each other by means of spring elements, wherein the spring elements comprise at least one cylindrical helical spring as rotation spring having one winding in the relaxed condition with one end guided back through the winding, and arranged substantially parallel to the buccal plane adjacent to the dentures.

50. Dentures according to claim 49, wherein the rotation spring has at least one crossing of a wire of the rotation spring, wherein the rotation spring on the crossing is provided with means for slidably keeping the wire onto each other at the location of the crossing, preferably a flexible synthetic ring.

51 . Dentures according to claim 50, wherein the rotation spring is further- more provided with a stop for keeping the means for slidably keeping onto each other at the crossing, wherein the stop preferably is a thickening arranged on the wire of the rotation spring, preferably a ring arranged on the wire.

52. Springy parts, suitable as spring elements for dentures according to any one of the preceding claims.

53. Device provided with one or more of the characterising measures described in the description and/or shown in the drawings.

54. Method comprising one or more of the characterising measures described in the description and/or shown in the drawings.