WO2006004541A1

WO2006004541A1 - A palatal plate and a method of producing said plate

Info

Publication number: WO2006004541A1
Application number: PCT/SE2005/001105
Authority: WO
Inventors: Karin Bengtsson; Iréne Johansson
Original assignee: Karin Bengtsson; Johansson Irene
Priority date: 2004-07-07
Filing date: 2005-07-05
Publication date: 2006-01-12
Also published as: SE529012C2; SE0401788D0; SE0401788L

Abstract

The present invention relates to a palatal plate having a stimulating member, comprising a thin-walled curved portion (2), the convex surface (8) of which being adapted to the palate of a user, a front edge portion (5), a rear edge portion (6) and two side edge portions (7A, 7B), as well as retainer means (3, 4) for retaining the palatal plate (1) inside the user's mouth, said stimulating member (9) being at least essentially chemically integrated with the inner surface (16) of said curved portion (2), and in that said retainer means (3, 4) are at least essentially formed from a material that is chemically integrated with the material of said curved plate (2), and that the means are designed to allow for a low total weight of the palatal plate (1).

Description

A PALATAL PLATE AND A METHOD OF PRODUCING SAID PLATE

TECHNICAL FIELD

5 The present invention relates to a palatal plate comprising a thin-walled curved portion, the convex surface of which being adapted to the palate of a user, a front edge portion, a rear edge portion and two side edge portions, as well as retainer means for retaining the palatal plate inside the user's mouth.

PRIOR ART

Different types of palatal plates are previously known. For example, palatal plates have been used for long in connection with orthodontics in order to achieve a stable attachment of correction elements adapted to exert a pressure on the teeth for which they are intended. It is also known to use palatal plates for orofacial purposes, e.g. in 5 order to provide stimulating members intended to aid a person in improving faculty of speech. A palatal plate of the latter type is described in an article from 1998, "Flexible palatal plate in speech therapy in children with Down's syndrome" by Karin Bengtsson and Irene Johansson, hi this connection, reference is also made to US 5,257,930, that discloses a palatal plate with particular devices for stimulation of the ability to pronounce an apical r. It is also known to use palatal plates for other purposes, such as to cover a palatal defect.

Li common for all known palatal plates according to the above, is that they are complex and laborious to produce, since the design/structure is such that a multi-step process is required for the production. Moreover, the production most often requires advanced handicraft skill. All in all, this means that today there is a very limited selection of palatal plates, and that the costs for a palatal plate are relatively high. Moreover, some users experience that known palatal plates are uncomfortable and cumbersome to use, among other things depending on the design of the retainer means. Palatal plates of today can be experienced as especially cumbersome to users in need of varying additional devices, such as varying types of stimulating members.

BRIEF ACCOUNT OF THE INVENTION

It is a purpose of the present invention to eliminate or at least minimize the above mentioned problems, which is achieved by a palatal plate comprising a thin-walled curved portion, the convex surface of which being adapted to the palate of a user, a front edge portion, a rear edge portion and two side edge portions, as well as retainer means for retaining the palatal plate inside the user's mouth, characterised in that said retainer means at least partly are formed from a material that is chemically integrated with the material in said curved plate, and that the means are designed to allow for a low total weight of the palatal plate.

Thanks to the invention, a palatal plate can be achieved which allows for production in a very rational way, at a relatively low cost, and that also allows for production thereof at a very low weight. Moreover, the production of a palatal plate according to the method of the invention does not to the same extent as previously require advanced handicraft work, which considerably improves the possibility of creating a good availability. In total, the invention enables palatal plates to be available to a considerably larger part of the earth's population than was previously the case. Also, palatal plates according to the invention allow for a convenient possibility for users in need of varying additional devices, such as varying types of stimulating members, not having to conduct cumbersome adaptation of the single palatal plate, by instead being able to own several palatal plates of differing "equipment".

According to further aspects of the invention:

• said retainer means are formed from at least two, preferably at least three, even more preferred at least four, discrete elements, at least one element being arranged at each edge portion, which results in an increased possibility of producing a palatal plate having retainer means of low weight,

• said discrete elements are arranged to retain the palatal plate of the user by interaction with dental surfaces facing the palate, in the upper row of teeth of the user, which results in the advantage that the retainer means can be very compact,

• the weight of the dental plate is between 0.5 and 5 grams, preferably between 0.8 and 3 grams, resulting in the advantage that there is very little influence of gravity on the retaining of the palatal plate,

• said means are provided with a curved outer surface arranged to interact with the row of teeth, in the recess between two adjoining teeth, for retaining of the palatal plate, which allows for a simple arrangement in order to create the contact surfaces maintaining a retaining action on the palatal plate,

• the thickness of essential portions of the base part is between 0,3 and 3 mm, preferably less than 2 mm, more preferred between 0.5 and 1.5 mm, which besides allowing for a low weight also results in optimum comfort for the user,

• the thickness, at least partly, of the lateral portions included in the base part, close to a transitional zone to the retainer means, at least partly and preferably is between 0.3 and 2 mm, preferably between 0.5 and 1.5 mm, more preferred between 0.6 and 1 mm, enabling creating of a beneficial, built-in elasticity.

• a stimulating member is arranged at an inner surface of said curved portion, allowing for a very rational possibility to provide a palatal plate with stimulating members,

• at least to an essential part, said stimulating members are chemically integrated with said curved portion, which contributes to the maintaining of a low weight and rational production,

• said stimulating member consists of a number of elevations, preferably arranged in close proximity to each other, which is an especially efficient way of arranging stimulating members,

• between the convex surface and the end surface of the front surface, the transition at the front edge forms an acute angle, whereby a beneficially comfortable transition can be achieved at the front edge.

The invention also relates to a method of producing a palatal plate according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the following, the invention will be described in greater detail with reference to the attached drawing figures, of which:

Fig. 1 shows a preferred embodiment of a palatal plate according to the invention, as seen in a perspective obliquely from above,

Fig. 2 shows the palatal plate according to Fig. 1, as seen in a planar view, Fig. 3 shows a cross-section along line III- III of Fig. 2,

Fig. 4 shows a longitudinal section along line IV-IV of Fig. 2,

Fig. 5 shows an alternative embodiment of a palatal plate according to the invention, as seen in a perspective obliquely from above,

Fig. 5A shows a longitudinal section (limited portion) along line Va-Va in Fig. 5, Fig. 6 shows a palatal plate according to Figs. 1-4, provided with a stimulating member according to a specific, preferred embodiment according to the invention,

Fig. 7 shows the palatal plate according to Fig. 6, as seen in a planar view,

Fig. 8 shows a cross-section along line VIII-VIII of Fig. 7,

Fig. 9 shows an additional modification of a palatal plate according to the invention, as seen in a perspective obliquely from above,

Fig. 10 shows the palatal plate according to Fig. 9, as seen in a planar view, and

Fig. 11 shows a longitudinal section along line XI-XI of Fig. 10. DETAILED DESCRIPTION

Fig. 1-4 shows a preferred embodiment of a palatal plate 1 according to the invention. The palatal plate 1 consists of a curved base plate 2, having an upper convex surface 8 adapted to the shape of the person intended to carry the palatal plate. The base plate 2 is relatively thin-walled, having a thickness T of which essential parts suitably are in the range of 0.3-3 mm. The drawings show that the base plate can be of about uniform thickness, meaning that the lower surface 16 is of principally the same shape as the convex surface 8, but instead being concave. Fig. 3 shows that the base plate 2 can be divided in two lateral portions 2L and one central portion 2C. The base plate 2 has a front 5 and a rear 6 edge, respectively, which are suitably adapted to a front row of teeth and the end of the palate, respectively, in order to make the fitting of the palatal plate 2 to the user as precise and comfortable as possible. The side edge portions 7 A, 7B are also adapted to the upper row of teeth of the user, such that the respective edge 7 A, 7B can be comfortably fitted to the palate of the user, in the space formed inside the upper row of teeth. At about the middle of the respective side edge 7 A, 7B, two retainer means 3, 4 are arranged at each side. The retainer means 3, 4 are formed as spheres. These spheres are integrated with the base plate 2, and accordingly they are fixedly attached thereto.

In a planar view as seen from above, see Fig. 2, it is shown that the spheres 3, 4 are positioned such that their centre C is positioned in close proximity to the imagined extension of the side edge 7A, 7B. It is also clear from Fig. 2, that the radius R is constant, in a horizontal plane of each sphere, such that its contour forms a circle, as seen from above. It is clear from Fig. 3 that also in the vertical plane, the sphere has a constant radius r. As the same radius (R, r) is used in all planes, each sphere forms a symmetric ball, apart from the portion at which there is transition 43 to the actual base plate 2. This transition (see Fig. 3) is arranged at the lower end of the respective retainer means 3, 4, such that the retainer means 3, 4 project upwards, in the elongation of the extension of the lateral portions 2L of the palatal plate, as seen in a cross-section according to Fig. 3. By this positioning of the retainer means 3, 4, the outer, curved surfaces 32, 42 are formed, which form abutment surfaces in contact with the inner portion of the upper row of teeth. It is furthermore clear from Fig. 2 that the retainer means 3, 4 are positioned with the "peaks" thereof at a given distance Y from each other, as seen in a planar view from above, corresponding to a distance X between the means, such that two proximate tooth gaps (not shown) are formed in the user of the palatal plate 1. Accordingly, the "peaks" are positioned to coincide with the position of two proximate tooth gaps of the user.

According to a preferred method of producing a palatal plate 1 according to the invention, free shape production is used, in which the palatal plate 1 and the retainer means 3, 4 are produced in one step by building up the palatal plate in layers (until it reaches its final shape). Thereby, methods known per se are used, such as laser sintering or layered sintering, by use of a three-dimensional, digitalized master for the palatal plate 1. In a manner known per se, this digitalized model can be achieved either by reading an impression in a computer, or by some type of direct digitalization by means of scanning. Some type of suitable polymer, such as polyamide 12, is used as a base material for the palatal plate 1. hi certain applications, it may be suitable to coat the palatal plate by a surface coating, containing silicon e.g., in order to obtain a desired surface property.

Clamping force is primarily used, but also friction to some extent, between the retainer means 3, 4 and the upper row of teeth of the user, when a palatal plate 1 according to the invention is used. Due to some elasticity in the palatal plate 1 and/or the retainer means 3, 4, the effect is achieved that the retainer means 3, 4 fix the palatal plate 1 in the intended position by pressing, with a certain limited clamping force, against one tooth gap each, such that contact is achieved between the respective retainer means 3, 4 and at least (two points in total) one point on each tooth adjacent the tooth gap where the retainer means 3, 4 is positioned. The clamping force, transferred by the contact points, will result in reaction forces as well as a certain friction that will give an adequate fix of the palatal plate 1 at the palate. A desired elasticity can beneficially be formed by making the lateral portions 2L relatively thin (at least close to the transitional zone 43), such that these portions allow for a desired built-in elasticity. Accordingly, it is possible, and sometimes also desirable, that the lateral portions 2L (at least partly) are somewhat thinner than the main thickness of the central portion 2C. hi this connection it can also be mentioned that the thickness in some cases and in particular portions can be allowed to exceed the main thickness T of the base plate 2, e.g. when the palatal plate is used to cover a deformation (e.g. a cleft palate) in the palate, in which case it may be beneficial to arrange portions of considerably larger thicknesses, e.g. in order to give extra comfort or an adequate stiffness.

One reason contributing to that this new retaining principle works well according to the invention, is that the palatal plate 1 will have a low weight thanks to its design (choice of material, compact retainer means, relatively low thickness etc.). Accordingly, the gravity acting on a palatal plate 1 according to the invention is relatively limited, which means that a relatively low friction/clamping force is adequate to achieve desired fixing of the palatal plate 1. According to a preferred embodiment, the weight of the palatal plate should therefore not exceed 5 grams, more preferred not exceed 3 grams, since in that case the clamping force might have to be increased to a level that the user may experience as being uncomfortable.

Fig. 5 shows an alternative embodiment of a palatal plate according to the invention. The basic principles of the palatal plate shown in Fig. 5, are in principle the same as what is shown in Figs. 1-4, which is also clear from the fact that the same reference numerals have been used for similar details. Therefore, only the differences will be described in the following. One important difference is the arranging of the end surface 5 A at the front edge 5 of the palatal plate 1. It is clear from Fig. 5 that the transition from the upper surface 8 to said end surface 5 A has been formed here such that an acute angle is formed (i.e. less than 90°), while Fig. 4 shows this angle to be obtuse. Tests have shown that many persons experience it much more comfortable when this angle is acute. Another important difference is that the retainer means 3, 4 have been positioned at another distance as compared to that shown in Figs. 1-4. The rear retainer means is placed at the same position as the rear retainer means in Figs. 1-4, but the front retainer means is moved further to the front edge 5 of the base portion, such that a larger distance Y is formed between two adjacent retainer means 3, 4. The principle of a palatal plate 1 according to Fig. 5 is that retaining at two tooth gaps on each side of an intermediate tooth gap is used instead of at two adjacent tooth gaps. Another difference shown in Fig. 5 is that the design of the retainer means 3, 4 has been modified. Instead of spherical, symmetrical elements, each retainer means has been provided at its top with a planar surface 31 and 41, respectively. All the same, the inner limit surface of each retainer means 3, 4 is essentially planar. However, the outer limit surface 42, intended by a claming force to abut against the upper row of teeth, is provided with a curved outer surface 32, 42, quite according to the principles described above.

Furthermore, the embodiment shows that the radius R need not be constant, but that an outer surface 42 can be used having a configuration that deviates from a circle, whereby it is realised that the chosen design advantageously can be varied depending on the shape of the upper row of teeth of the user.

Fig. 6-8 show a palatal plate in principle identical with that shown in Figs. 1-4, except that this palatal plate 1 also has been provided with a stimulating member 9. In this embodiment, the stimulating member 9 consists of a number of essentially cone shaped units 10, arranged close to each other near the rear edge portion 6, and having an extension that is in principle parallel with the rear edge portion 6. It is clear from Fig. 8 that the stimulating member 9 suitably extends along the entire middle and essentially planar portion of the inner surface 16 of the palatal plate. This design of the stimulating member 9 is suitable e.g. in order to activate the rear portion of the tongue in order e.g. to stimulate a closing of the mouth in order to effect breathing through the nose instead.

Fig. 9 shows another embodiment in accordance with the invention. A first modification is that an additional retainer means 3, 4 is used on each side 7 A, 7B of the palatal plate 1. Accordingly, three retainer means are used on each side 7 A, 7B. The design of the retainer means 3, 4 is the same as shown and described in connection with Fig. 5. However, in this case, the distance Y between the "peaks" of each retainer means is the same as the distance X between two adjacent tooth gaps of the user of the palatal plate 1. Another difference that is shown is that close to the front edge 5 of the palatal plate, the palatal plate 1 is provided with a stimulating member 9. In this case, the stimulating member 9 consists of two cone shaped details positioned at a central position of the palatal plate, close to each other in a direction that coincides with the longitudinal direction of the palatal plate 1, such that this stimulating member 9 will be positioned at the user's tip of the tongue. It is clear from Fig. 11 that the components of the stimulating member 9 is prominently shaped as "peaks" 15. In the shown case, they are formed as truncated cone elements 14 having a rounded top, but it is realised that this is only one of many possibilities to create prominent elements, i.e. that different designs can be used depending on individual need, which means that sometimes it may even be pointed peaks or the shape of a crater that is optimal.

The invention is not limited to what has been described above but may be varied within the scope of the claims. For example, the skilled man will realise that the retainer means 3, 4 can be positioned with great variations, e.g. by sometimes using more than three retainer means, and that sometimes a single retainer means can be adequate. Moreover, it is realised that the retainer means need not be symmetrically arranged on each side, i.e. that in some cases it may be suitable to have e.g. three retainer means on one side and two retainer means on the other side, or one on one side and two on the other side, depending among other things on the form on the user's upper row of teeth, as well as the intended application. It is also realised that the retainer means 3, 4 in some cases are in principle exactly adapted to the respective tooth gap, which however must be balanced against the fact that in many cases it is beneficial at production to use a predetermined configuration of these elements, such as a spherical configuration. Furthermore, it is realised that a palatal plate 1 according to the invention can be produced also in other ways than described, such as by casting. Moreover, it is realised that the palatal plate 1 according to the invention beneficially can be used in many different applications, and that the basic design according to the invention can be used in order to produce palatal plates of great variation, such as a palatal plate having stimulating members both at the front and the rear edges, and that additional details (e.g. loosely hanging stimulating members) can be applied later (i.e. in a subsequent step). Furthermore, the preferred method of free shape production of the palatal plate can be used also to produce such loosely hanging stimulating members, which is an additional advantage of using this principle of production. It is furthermore realised that stimulating members (or other members) also can be arranged distally with respect of the row of teeth, i.e. between the lip and the row of teeth, at a plate according to the invention.

Claims

1. A palatal plate having a stimulating member, comprising a thin-walled curved portion (2), the convex surface (8) of which being adapted to the palate of a user, a front edge portion (5), a rear edge portion (6) and two side edge portions (7 A, 7B), as well as retainer means (3, 4) for retaining the palatal plate (1) inside the user's mouth, c haracteris ed in that said stimulating member (9) is at least essentially chemically integrated with the inner surface (16) of said curved portion (2), and in that said retainer means (3, 4) are at least essentially formed from a material that is chemically integrated with the material of said curved plate (2), and that the means are designed to allow for a low total weight of the palatal plate (1).

2. A palatal plate according to claim 1, charac teri s e d in that said retainer means (3, 4) are formed from at least two, preferably at least three, even more preferred at least four, discrete elements, at least one element being arranged at each edge portion (7 A, 7B).

3. A palatal plate according to claim 2, characteri s ed in that said discrete elements are arranged to retain the palatal plate (1) of the user by interaction with dental surfaces facing the palate, in the upper row of teeth of the user.

4. A palatal plate according to claim 3, c h arac t eri s ed in that the weight of the palatal plate (1) is between 0.5 and 5 grams, preferably between 0.8 and 3 grams.

5. A palatal plate according to any one of the preceding claims, c haracteri s e d in that said means (3, 4) are provided with a curved outer surface (42) arranged to interact with the row of teeth, in the recess between two adjoining teeth, for retaining of the palatal plate (1).

6. A palatal plate according to any one of the preceding claims, charac teri s e d in that the thickness (T) of an essential part of the base portion (2) is between 0.3 and 3 mm, preferably less than 2 mm, and even more preferred between 0.5 and 1.5 mm.

7. A palatal plate according to any one of the preceding claims, charac t eri s e d in that the thickness (T), at least partly, of the lateral portions (2C) included in the base part (2), preferably at least close to a transitional zone (43) to the retainer means (3, 4), is between 0.3 and 2 mm, preferably between 0.5 and 1.5 mm, and even more preferred between 0.6 and 1 mm.

8. A palatal plate according to claim 1, charac teri s e d in that said stimulating member (9) consists of a number of elevations (10), preferably arranged in close proximity to each other.

9. A palatal plate according to any one of the preceding claims, ch arac teri s e d in that the transition at the front edge (5) between the convex surface (8) and the end surface of the front edge (5A), forms an acute angle.

10. A method of producing a palatal plate having a stimulating member, comprising a thin-walled curved portion (2), the convex surface (8) of which being adapted to the palate of a user, a front edge portion (5), a rear edge portion (6) and two side edge portions (7 A, 7B), as well as retainer means (3, 4) for retaining the palatal plate (1) inside the user's mouth, characteri s e d in that said retainer means (3 , 4) are produced in the same process of production as said thin-walled, curved portion, in that free shape production is used, and in that at least one stimulating member (9) is produced in the same process.

11. A method according to claim 10, ch aract eri s ed in that a digitalized, three- dimensional image is used as a master for the production of said palatal plate.

12. A method according to claim 10 or 11, characteri s ed in that at least one stimulating member (9) is produced such that it is moveably arranged at the palatal plate.