Mouthpiece disc, mold for manufacturing mouthpiece disc, apparatus for manufacturing mouthpiece disc, and method for manufacturing mouthpiece disc

Abstract

The present invention provides, inter alia, a mouthpiece disc in which an adhesive is not used, which has high adhesion between resin layers, and which is adjusted in thickness at a back tooth portion and a front tooth portion, and a method for manufacturing the same. The mouthpiece disc is provided with a first resin layer 1 formed from a first resin and a second resin layer 2 formed from a second resin and joined to the first resin layer 1, wherein the second resin layer 2 has a thick part 21 in which a prescribed region is thicker than the surrounding area. Also, the mouthpiece disc may further include a third resin layer 3 formed from a third resin and joined to the second resin layer 2 on the opposite side from the first resin layer 1.

Description

Mouthpiece disc, mold for manufacturing mouthpiece disc, manufacturing device for mouthpiece disc, and manufacturing method for mouthpiece disc

[0001] The present invention relates to a mouthpiece disc, a mold for manufacturing a mouthpiece disc, an apparatus for manufacturing a mouthpiece disc, and a method for manufacturing a mouthpiece disc.

[0002] In recent years, awareness of mouthpiece orthodontics has been increasing in the field of orthodontics. This is because mouthpiece orthodontics has many advantages, such as less pain, the orthodontic treatment is not noticeable, there is no need to worry about metal allergies because it does not use metal, it can be removed when eating or brushing your teeth, and it requires fewer visits to the dentist.

[0003] The functions required of mouthpiece discs used in mouthpiece orthodontics include facilitating the movement of teeth during orthodontics and stabilizing the position of the teeth, as well as being able to be attached to the teeth so that they do not easily come off, being durable against clenching, and maintaining the molded shape.However, some mouthpiece discs have properties that are contrary to those of general materials such as engineering plastics, and it is difficult to satisfy all of the basic functions mentioned above if they are made from a single resin.

[0004] Therefore, as a method of utilizing the individual characteristics of resin materials, two-layered mouthpieces have been devised, each consisting of a high-elasticity resin for forming a shape-retaining portion that maintains the shape of the mouthpiece and a low-elasticity resin for tooth movement, and three-layered mouthpieces (e.g., Patent Document 1) in which a low-elasticity resin is sandwiched between two high-elasticity resins. Here, such mouthpieces are molded by heating a two-layered or three-layered mouthpiece disk. JP 2020-522405

[0005] However, conventional mouthpiece discs have a two-layer or three-layer structure, where a resin with a low modulus of elasticity and a resin with a high modulus of elasticity are bonded together with adhesives, raising concerns about the effects of harmful substances contained in the adhesive on the human body. Furthermore, those that use adhesives tend to peel off easily. Furthermore, using adhesives increases costs and increases the thickness of the mouthpiece disc, so the options for materials and thicknesses of multi-layer mouthpieces available on the market are not necessarily wide.

[0006] Another method involves simultaneously molding three layers using co-extrusion molding. However, when using resins with different melting points, if the melting points of the materials for each layer are too different, the adhesive strength of the thermal fusion bond weakens and the surface material deteriorates. Another problem is that erosion of each layer can lead to uneven thickness. Weakened adhesive strength leads to a loss of the mouthpiece's restoring force, reducing the amount of tooth movement. Furthermore, material deterioration makes it impossible to continuously utilize the restoring force. Furthermore, uneven layer thickness leads to uneven restoring force, making it impossible to control tooth movement.

[0007] Furthermore, because the thickness of each layer of conventional mouthpiece discs was uniform, when the mouthpiece was molded the front teeth area was thinner than the back teeth area, which caused the back teeth to sink, leading to problems such as poor bite alignment after treatment and temporomandibular joint disorder.

[0008] Therefore, the present invention aims to provide a mouthpiece disc that does not use adhesive, has high adhesion between resin layers, and has thickness adjusted between the back teeth and front teeth, a mold for manufacturing a mouthpiece disc, a mouthpiece disc manufacturing device, and a mouthpiece disc manufacturing method.

[0009] In order to achieve the above-mentioned object, the mouthpiece disc of the present invention is a mouthpiece disc comprising a first resin layer made of a first resin and a second resin layer made of a second resin and bonded to the first resin layer, wherein the second resin layer has a thick portion in a predetermined area that is thicker than the surrounding area.

[0010] The mouthpiece disc of the present invention may also include a third resin layer made of a third resin and bonded to the second resin layer on the side opposite to the first resin layer.

[0011] Here, the thick portion may be formed to be thicker than the surrounding area by 0.1 mm or more and 0.3 mm or less.

[0012] The second resin may have a lower modulus of elasticity than the first resin.

[0013] The second resin may have a lower modulus of elasticity than the third resin.

[0014] At least one of the surfaces of the first resin layer, the second resin layer, and the third resin layer may have a functional shape having a predetermined function.

[0015] The mouthpiece of the present invention is also characterized in that it is molded so that the difference in thickness between the occlusal portions of the molars and the occlusal portions of the front teeth is 15% or less of the thickness of the occlusal portions of the molars.

[0016] The mold for manufacturing a mouthpiece disc of the present invention is a mold consisting of a first mold and a second mold for manufacturing a mouthpiece disc by supplying resin onto a first film, wherein the first mold has a first sealing means for sealing the space between the inner surface of the first mold and the outer surface of the first film, and a first air intake passage that penetrates from the outer surface to the inner surface of the first mold, and is characterized in that the inner surface of at least one of the first mold and the second mold has a recess in a predetermined area that is deeper than its surroundings.

[0017] The present invention also provides a mold for producing a mouthpiece disc, which comprises a first mold and a second mold for producing a mouthpiece disc by supplying resin between a first film and a third film, wherein the first mold has a first sealing means for sealing the gap between the inner surface of the first mold and the outer surface of the first film, and a first air intake passage that penetrates from the outer surface to the inner surface; the second mold has a resin supply flow path for supplying the resin through a resin supply hole formed in the third film, a second sealing means for sealing the gap between the inner surface of the second mold and the outer surface of the third film, and a second air intake passage that penetrates from the outer surface to the inner surface of the second mold; and the inner surface of at least one of the first mold and the second mold has a recess in a predetermined area that is deeper than its surroundings.

[0018] Here, the recess may have a shape that widens from the center toward the outer edge of at least one of the first mold and the second mold.

[0019] Here, the resin supply flow path may have two or more discharge holes arranged at equal angles on a circumference for supplying resin between the first film and the third film.

[0020] The second mold may have a protrusion that can fit into the resin supply hole formed in the third film.

[0021] Furthermore, the inner surface of at least one of the first mold and the second mold may have an uneven portion for forming a functional shape with a predetermined function on the surface of the mouthpiece disc.

[0022] Furthermore, the mouthpiece disc manufacturing apparatus of the present invention is a manufacturing apparatus for manufacturing mouthpiece discs, and is characterized by comprising: a mold for manufacturing mouthpiece discs; a resin supply means for supplying resin into the mold; a pressure reducing means for reducing the pressure between the inner surface of the first mold and the outer surface of the first film via a first air intake path; and a mold opening / closing means for opening and closing the first and second molds of the mold.

[0023] The method for manufacturing a mouthpiece disc of the present invention is a method for manufacturing a mouthpiece disc using a mold consisting of a first mold and a second mold, and is characterized by comprising: a first film surface modification step of applying a physical or chemical surface treatment to a first surface of a first film made of a first resin; and a resin supply step of placing the first film on the inner surface of at least one of the first mold and the second mold, the mold having a recess in a predetermined area that is deeper than its surroundings, and supplying a second resin under pressure to the first surface of the first film until a thick portion is formed along the recess.

[0024] The method for manufacturing a mouthpiece disc of the present invention is a method for manufacturing a mouthpiece disc using a mold consisting of a first mold and a second mold, and is characterized by comprising: a first film surface modification step of applying a physical or chemical surface treatment to a first surface of a first film made of a first resin; a third film surface modification step of applying a physical or chemical surface treatment to a first surface of a third film made of a third resin and having a resin supply hole; and a resin supply step of placing the first film on the inner surface of at least one of the first mold and the second mold, the mold having a recess in a predetermined area that is deeper than its surroundings, and placing the third film on the inner surface of the other mold, and supplying a second resin under pressure between the first surface of the first film and the first surface of the third film until a thick portion along the recess is formed.

[0025] Here, the recess may have a shape that widens from the center toward the outer edge of at least one of the first mold and the second mold.

[0026] Here, the inner surface of at least one of the first mold and the second mold may have an uneven portion for forming a functional shape with a predetermined function on the surface of the mouthpiece disc.

[0027] The present invention can provide a method for manufacturing a mouthpiece disc that does not use adhesive, has high adhesion between resin layers, and has a thickness that does not change between the back teeth and front teeth, and a mouthpiece disc.

[0028] 1 is a cross-sectional view of a mouthpiece disc of the present invention having a two-layer structure. FIG. 2 is a cross-sectional view of a mouthpiece disc of the present invention having a three-layer structure. FIG. 3 is a plan view of a mouthpiece disc of the present invention. FIG. 4 is an exploded perspective view for explaining the configuration of a mouthpiece disc of the present invention. FIG. 5 is a plan view of the inner surface side of a first mold constituting a mold for manufacturing a mouthpiece disc of the present invention. FIG. 6 is a cross-sectional view of the first mold constituting a mold for manufacturing a mouthpiece disc of the present invention. FIG. 7 is a bottom view (view as seen from the inner surface side) of a second mold constituting a mold for manufacturing a mouthpiece disc of the present invention. FIG. 8 is a cross-sectional view of the second mold constituting a mold for manufacturing a mouthpiece disc of the present invention. FIG. 9 is a plan view of the outer surface side of the second mold constituting a mold for manufacturing a mouthpiece disc of the present invention. FIG. 10 is an explanatory diagram showing a first step of a method for manufacturing a mouthpiece disc of a two-layer structure according to the present invention. FIG. 11 is an explanatory diagram showing a second step of the same manufacturing method. FIG. 12 is an explanatory diagram showing a third step of the same manufacturing method. FIG. 13 is an explanatory diagram showing a fourth step of the same manufacturing method. FIG. 14 is an explanatory diagram showing a fifth step of the same manufacturing method. FIG. 15 is an explanatory diagram showing a sixth step of the same manufacturing method. FIG. 16 is an explanatory diagram showing a first step of a method for manufacturing a mouthpiece disc of a three-layer structure according to the present invention. FIG. 17 is an explanatory diagram showing a second step of the same manufacturing method. 1 is an explanatory diagram showing a third step of the manufacturing method; 2 is an explanatory diagram showing a fourth step of the manufacturing method; 3 is an explanatory diagram showing a fifth step of the manufacturing method; 4 is an explanatory diagram showing a sixth step of the manufacturing method; 5 is a cross-sectional photograph of a mouthpiece disc of the present invention at 400x magnification; 6 is a cross-sectional photograph of a mouthpiece disc of the present invention at 2000x magnification.

[0029] The mouthpiece disc of the present invention will be described below with reference to Figures 1 and 2. Figure 1A shows one embodiment of a mouthpiece disc. The mouthpiece disc 100 shown in Figure 1A is composed of a first resin layer 1 made of a first resin and a second resin layer 2 made of a second resin and bonded to the first resin layer 1.

[0030] Here, the first resin layer 1 mainly serves to form a shape-retaining portion that maintains the shape of the mouthpiece. Because the mouthpiece is used in the oral cavity, the first resin used for the first resin layer 1 is preferably non-toxic. Specific examples of such resins include glycol-modified polyethylene terephthalate (PETG), glycol-modified polycyclohexylene dimethylene terephthalate (PCTG), and polycarbonate (PC).

[0031] The second resin layer 2 mainly provides a restoring force, applying stress to the teeth to promote tooth movement. The second resin used in the second resin layer 2 may be any resin as long as it has a restoring force sufficient to apply stress to the teeth and promote tooth movement, and examples of such resins include thermoplastic polyurethane (TPU) and thermoplastic polyester (TPC). It is also preferable that the second resin is non-toxic.

[0032] Furthermore, because the thickness of each layer of conventional mouthpiece discs was uniform, the thickness of the front teeth area was thinner than that of the back teeth area when the mouthpiece was molded. This caused the back teeth to sink when the mouthpiece was worn due to the difference in thickness, leading to problems such as poor bite alignment after treatment and temporomandibular joint disorder.

[0033] 1, the second resin layer 2 has a thick portion 21 in a predetermined region that is thicker than the surrounding area. In this embodiment, the thick portion 21 protrudes from the back surface (the surface facing the first resin layer 1) of the second resin layer 2 at a position offset from the center of the second resin layer 2 (a position closer to the right in FIG. 1A), and the thick portion 21 is formed so that its surface is thicker than the surface of the second resin layer 2 other than the thick portion 21.

[0034] By providing the thick portion 21 as described above, when a mouthpiece is formed using a mouthpiece disc, if this thick portion 21 is placed in the front teeth area, the difference in thickness between the occlusal parts of the back teeth and front teeth can be reduced, and problems with malocclusion and temporomandibular joint disorder can be prevented.

[0035] Note that a protruding portion 1a is provided at a portion of the first resin layer 1 corresponding to the thick portion 21 by being pressed by the thick portion 21. The protruding portion 1a is formed so that its surface is thicker than the surface of the first resin layer 1 other than the protruding portion 1a.

[0036] Fig. 1B shows another embodiment of a mouthpiece disc. Mouthpiece disc 100A shown in Fig. 1B is composed of a first resin layer 1 made of a first resin, a second resin layer 2 made of a second resin and bonded to first resin layer 1, and a third resin layer 3 made of a third resin and bonded to the second resin layer 2 on the side opposite to first resin layer 1.

[0037] Here, the third resin layer 3 also serves to form a shape-retaining portion that mainly maintains the shape of the mouthpiece. Because the mouthpiece is used in the oral cavity, the third resin used in the third resin layer 3 is preferably non-toxic. Specific examples of such resins include glycol-modified polyethylene terephthalate (PETG), glycol-modified polycyclohexylene dimethylene terephthalate (PCTG), and polycarbonate (PC).

[0038] Here, the second resin may have a lower modulus of elasticity than the first resin and the third resin.

[0039] The planar shape of the thick portion 21 may be any shape as long as it allows the thickness of the front teeth portion to be large and the thickness of the back teeth portion such as the premolars and molars to be small when molding the mouthpiece.

[0040] 2A and 2B show yet another embodiment of a mouthpiece disc. Similar to mouthpiece disc 100A shown in Fig. 1B, this mouthpiece disc 100B is composed of a first resin layer 1, a second resin layer 2, and a third resin layer 3. In a plan view of mouthpiece disc 100B, thick portion 21 provided in second resin layer 2 widens (its width along the circumferential direction gradually increases) from the center toward the outer edge of mouthpiece disc 100B, and has a generally fan-like shape with arc-shaped inner and outer circumferential edges in the radial direction.

[0041] By providing the thick portion 21 having an approximately fan shape as described above, it is possible to manufacture a mouthpiece that fits the size of the front teeth by using the center side of the mouthpiece disc 100B when the width of the front teeth is small, and using the outer edge side of the mouthpiece disc 100B when the width of the front teeth is large.

[0042] Furthermore, the thickness of the thick portion 21 may be any thickness as long as it can reduce the difference in thickness of the occlusal parts of the back teeth and front teeth when the mouthpiece is formed, but for example, the thick portion 21 may be formed to be larger than the surrounding area by 0.1 mm to 0.3 mm.

[0043] The mouthpiece disc of the present invention may be in the form of a sheet or plate, and may have any size suitable for forming a mouthpiece. For example, it may be in the form of a disk with a radius of 60 to 70 mm.

[0044] The thickness of the first resin layer 1 and the third resin layer 3 may be any thickness as long as they function as shape-retaining portions that maintain the shape of the mouthpiece, but because they are placed inside the mouth, the thinner they are, the more comfortable they will feel when worn, and for example, a thickness of 0.1 mm to 1 mm can be used. The thickness of the second resin layer 2 may be any thickness as long as it provides a restoring force and applies stress to the teeth, but because they are placed inside the mouth, the thinner they are, the more comfortable they will feel when worn, and for example, a thickness of 0.1 mm to 1 mm can be used.

[0045] Furthermore, the mouthpiece disc of the present invention does not need to have two or three resin layers (it only needs to have a two-layer structure consisting of at least a first resin layer and a second resin layer), and may be composed of four or more resin layers including the above-mentioned first resin layer 1, second resin layer 2, and third resin layer 3.

[0046] Furthermore, the mouthpiece disc of the present invention may have a functional shape with a predetermined function on at least one of the surfaces of the first resin layer, the second resin layer, and the third resin layer. Here, the surface means the outermost surface of the mouthpiece disc 100, and in the case where the mouthpiece disc is composed of three layers, the first resin layer 1, the second resin layer 2, and the third resin layer 3, the outer surfaces of the first resin layer 1 and the third resin layer 3 correspond to the surface.

[0047] A functional shape refers to a shape that has a specific function, such as improving the ability to grip teeth or improving aesthetics by reflecting, scattering, refracting, diffracting, etc. Specific examples of functional shapes include prisms, lenticular shapes, linear Fresnel shapes, microlens shapes, pyramidal shapes, etc.

[0048] Furthermore, some people have poor tooth alignment, with their front teeth misaligned from the front. In such cases, it is convenient to have an alignment mark that allows the thick portion 21 to be rotated to align with the teeth when molding the mouthpiece. Therefore, as shown in Figures 2A and 2B, a recess or protrusion that functions as the alignment mark 110 may be formed as a functional shape.

[0049] That is, in the mouthpiece disc 100B shown in Figures 2A and 2B, an alignment mark 110 is formed at a predetermined location in the circumferential direction on the outer peripheral edge of the first resin layer 1, and an alignment mark 110 is also formed at a position on the outer peripheral edge of the second resin layer 2 corresponding to the alignment mark 110 formed on the first resin layer 1.

[0050] Furthermore, in mouthpiece disc 100B, a circular center hole 3a is formed in the radial center of third resin layer 3, which is a substantially circular plate, and a plurality of center marks 22a that can be positioned on the inner periphery of center hole 3a are formed in the radial center of second resin layer 2, which is also a substantially circular plate. When third resin layer 3 is overlaid on second resin layer 2, center mark 22a of second resin layer 2 is positioned on the inner periphery of center hole 3a of third resin layer 3. These center holes 3a and center marks 22a allow the radial center position of mouthpiece disc 100B to be determined and can serve as landmarks during mouthpiece molding.

[0051] Next, the mouthpiece of the present invention will be described. The mouthpiece of the present invention is molded from the mouthpiece disc as described above, and is characterized in that it is molded so that the difference in thickness between the occlusal portions of the molars and the anterior teeth is 15% or less of the thickness of the occlusal portion of the molars.

[0052] This reduces the difference in thickness between the occlusal areas of the back teeth and front teeth, preventing problems with malocclusion and temporomandibular joint disorders.

[0053] Next, an embodiment of a mold for manufacturing a mouthpiece disc of the present invention will be described. As shown in Figures 5A to 5F, this mold for manufacturing a mouthpiece disc 200 is used to supply resin onto first film 11 to manufacture mouthpiece disc 100 in the form shown in Figure 1A, and is composed of first mold 201 and second mold 202.

[0054] As shown in Figures 3A and 3B, the first mold 201 has a first sealing means 211 for sealing the space between the inner surface 201a (see Figure 5A) of the first mold 201 and the outer surface of the first film 11, and a first air intake passage 212 that penetrates from the outer surface 201b of the first mold 201 to the inner surface 201a.

[0055] Furthermore, a predetermined region of the inner surface of at least one of the first mold 201 and the second mold 202 has a recess 230 that is deeper than the surrounding area. In this embodiment, as shown in Fig. 3B, the recess 230 is formed in the inner surface 201a of the first mold 201.

[0056] The first mold 201 and the second mold 202 may be made of any material, such as a common material such as pre-hardened steel, and may be any size as long as the desired mouthpiece disc 100 can be produced inside the mold.

[0057] The first sealing means 211 may be any means capable of sealing the gap between the inner surface 201a of the first mold 201 and the outer surface of the first film 11, but for example, an O-ring tightly attached to the first mold 201 may be used.

[0058] The first air intake path 212 is for sucking in gas from the space surrounded by the first film 11, the first mold 201, and the first sealing means 211, and for adsorbing and fixing the first film 11. The first air intake path 212 may be formed in any size, shape, or position as long as it can suck in gas from the space surrounded by the first film 11, the first mold 201, and the first sealing means 211.

[0059] The recess 230 is for forming the thick portion 21 in the mouthpiece disc 100, where a predetermined area is thicker than the surrounding area, when resin is supplied. The recess 230 in this embodiment has a generally fan-like shape that fits the thick portion 21 so that the thick portion 21 can be molded. Specifically, the recess 230 is preferably formed deeper than the surrounding area by 0.1 mm to 0.3 mm.

[0060] Furthermore, the shape of the recess 230 may be any shape that allows for a larger thickness in the area surrounding the front teeth and a smaller thickness in the area surrounding the back teeth, such as the premolars and molars, when molding the mouthpiece. Preferably, the recess 230 has a shape that widens from the center of the mold toward the outer edge, such as the fan shape shown in Figure 3A.

[0061] Next, another embodiment of a mold for manufacturing a mouthpiece disc of the present invention will be described. As shown in Figures 6A to 6F, this mouthpiece manufacturing mold 200A is used to supply resin onto first film 11 and third film 31 to manufacture mouthpiece disc 100A of the form shown in Figure 1B, and is composed of first mold 201 and second mold 202.

[0062] 3A and 3B, the first mold 201 has a first sealing means 211 for sealing the gap between the inner surface 201a of the first mold 201 and the outer surface of the first film 11, and a first air intake passage 212 that passes through from the outer surface 201b to the inner surface 201a of the first mold 201. The first mold 201 is the same as that of the mold 200 used to manufacture the mouthpiece disc.

[0063] As shown in Figures 4A and 4B, the second mold 202 also has a resin supply flow path 223 for supplying resin through the resin supply hole 31a formed in the third film 31, a second sealing means 221 for sealing the space between the inner surface 202a of the second mold 202 and the outer surface of the third film 31, and a second air intake path 222 that penetrates from the outer surface 202b of the second mold 202 to the inner surface 202a.

[0064] In addition, a predetermined region has a recess 230 that is deeper than its surroundings on the inner surface of at least one of the first mold 201 and the second mold 202. In this embodiment, as shown in Figures 6A to 6F, the recess 230 is formed on the inner surface 201a of the first mold 201.

[0065] The first mold 201 and the second mold 202 may be made of any material, such as a common material such as pre-hardened steel, and may be any size as long as the desired mouthpiece disc 100A can be accommodated inside the mold.

[0066] The first sealing means 211 may be any means capable of sealing the gap between the inner surface 201a of the first mold 201 and the outer surface of the first film 11, but for example, an O-ring tightly attached to the first mold 201 may be used.

[0067] The first air intake path 212 is for sucking in gas from the space surrounded by the first film 11, the first mold 201, and the first sealing means 211, and for adsorbing and fixing the first film 11. The first air intake path 212 may be formed in any size, shape, or position as long as it can suck in gas from the space surrounded by the first film 11, the first mold 201, and the first sealing means 211.

[0068] The second sealing means 221 may be any means capable of sealing the gap between the inner surface 202a of the second mold 202 and the outer surface of the third film 31, but for example, an O-ring attached to the second mold 202 may be used.

[0069] 4A is for sucking in gas from the space surrounded by the third film 31, the second mold 202, and the second sealing means 221, and for adsorbing and fixing the third film 31. The second air intake path 222 may be formed in any size, shape, or position as long as it can suck in gas from the space surrounded by the third film 31, the second mold 202, and the second sealing means 221.

[0070] Furthermore, recess 230 is intended to create thick portion 21 in mouthpiece disc 100A, where a predetermined area is thicker than the surrounding area, when resin is supplied. In this embodiment, recess 230 is formed in a roughly fan shape that fits thick portion 21 so that thick portion 21 can be molded. Specifically, recess 230 is preferably formed deeper than the surrounding area by 0.1 mm to 0.3 mm.

[0071] Furthermore, the shape of the recess 230 may be any shape that allows for a larger thickness in the area surrounding the front teeth and a smaller thickness in the area surrounding the back teeth, such as the premolars and molars, when molding the mouthpiece. Preferably, the recess 230 has a shape that widens from the center toward the outer edge of the inner surface of the mold, such as the fan shape shown in Figure 3A.

[0072] 4A and 4B, the resin supply flow path 223 is for supplying resin from discharge holes 223a between the first film 11 and the third film 31. As shown in Fig. 4A, the resin supply flow path 223 preferably has two or more, preferably three or more, and more preferably six or more discharge holes 223a for supplying resin between the first film 11 and the third film 31 arranged at equal angles on the circumference.

[0073] Furthermore, the second mold 202 in this embodiment has a protrusion 224 that can fit into the resin supply hole 31 a formed in the third film 31. Here, the protrusion 224 protrudes from the inner surface 202 a of the second mold 202, at the periphery of the resin supply hole 31 a. Here, the discharge hole 223 a of the resin supply flow path 223 is formed in the upper surface of the protrusion 224.

[0074] 4B , the height of the upper surface of the convex portion 224 is formed to be located between the first film 11 and the third film 31, more preferably at the height of the inner surface of the third film 31. This makes it possible to prevent the resin from flowing around to the surface of the third film 31 facing the mold when the resin is supplied to the first film 11 and the third film 31, and allows the resin to be supplied efficiently between the first film 11 and the third film 31.

[0075] Furthermore, the inner surface of at least one of the first mold 201 and the second mold 202 may have an uneven portion for forming a functional shape with a predetermined function on the surface of the mouthpiece disc 100A. This allows the mouthpiece disc 100A to be given the above-mentioned functional shape. Specific examples of functional shapes include a prism shape, a lenticular shape, a linear Fresnel shape, a microlens shape, and a pyramid shape.

[0076] Next, the manufacturing apparatus of the present invention will be described. The manufacturing apparatus of the present invention is used to manufacture mouthpiece discs 100, 100A, and is mainly composed of molds 200, 200A described above, resin supply means, pressure reducing means, and mold opening / closing means for opening and closing first mold 201 and second mold 202 of molds 200, 200A.

[0077] The resin supply means is for supplying resin into the mold 200 via a resin supply flow path. The resin supply means may be any means capable of supplying resin into the mold 200, but may be configured, for example, to supply resin by pressurizing it with a pump into the resin supply flow path 223 of the mold 200.

[0078] The decompression means is for reducing the pressure between the inner surface 201a of the first mold 201 and the outer surface of the first film 11 via the first air intake path 212, and fixing the first film 11 to the inner surface 201a of the first mold 201. The decompression means may be any means capable of fixing the first film 11 to the inner surface 201a of the first mold 201, but may be configured to, for example, suck in the gas between the inner surface 201a of the first mold 201 and the outer surface of the first film 11 via the first air intake path 212 using a decompression pump or an ejector.

[0079] The mold opening / closing means is for opening and closing the first mold 201 and the second mold 202. Any means may be used as long as it can open and close the first mold 201 and the second mold 202, but for example, one mold may be fixed and the other mold may be moved by a hydraulic pump, an electric motor, or the like to open and close the mold.

[0080] Next, an embodiment of the method for manufacturing a mouthpiece disc of the present invention will be described. Figures 5A to 5F show the method for manufacturing a mouthpiece disc 100 using a mold 200 consisting of a first mold 201 and a second mold 202, and the method mainly comprises a first film surface modification step and a resin supply step.

[0081] Here, the first film surface modification step is a step of performing a physical or chemical surface treatment on the first surface of the first film 11 made of the first resin, which can improve the wettability of the first surface, thereby improving the adhesion between the first surface and the second resin supplied in the resin supply step described below.

[0082] Here, the surface treatment in the first film surface modification step can be any method that can improve the adhesion between the first surface of the first film 11 and the second resin, and for example, optical treatment can be used. Optical treatment is a method of modifying the first surface of the first film 11 using an excimer lamp, plasma, or the like. For example, oxygen plasma can be used to form highly hydrophilic functional groups (OH groups) such as carbonyl groups and carboxyl groups on the material surface, thereby chemically improving hydrophilicity. This can improve the adhesion and wettability between the first surface of the first film 11 (the surface facing the second resin layer 2) and the second resin.

[0083] In the resin supplying step, first, a mold 200 is prepared, which is at least one of a first mold 201 and a second mold 202, and has a recess 230 in which a predetermined area is deeper than the surrounding area. Here, the mold means the mold of the present invention described above. Fig. 5A shows the mold 200 having the recess 230 on the first mold 201 side.

[0084] Next, the first film 11 is placed on the inner surface 201a side of a first mold 201 having a recess 230 (see FIG. 5B). Next, a second mold 202 is placed in the cavity (molding resin filling space) of the first mold 201, leaving a gap above the first film 11 that corresponds to the thickness of the second resin layer 2 to be formed (see FIG. 5C). Next, the second resin is supplied under pressure to the first surface of the first film 11 until the thick portion 21 is formed along the recess 230 (see FIG. 5D).

[0085] Thereafter, the second resin is cooled and solidified, and the second resin layer 2 is formed on the first surface of the first film 11. Then, the second mold 202 is removed from the cavity of the first mold 201 (see FIG. 5E). Finally, the mouthpiece disc 100 is removed from the first mold 201 (see FIG. 5F). The first film 11 becomes the first resin layer 1 of the mouthpiece disc 100.

[0086] Here, the first film 11 mainly serves to form a shape-retaining portion that maintains the shape of the mouthpiece. Because the mouthpiece is used in the oral cavity, the first resin used for the first film 11 is preferably non-toxic. Specific examples of such resins include glycol-modified polyethylene terephthalate (PETG), glycol-modified polycyclohexylene dimethylene terephthalate (PCTG), and polycarbonate (PC).

[0087] The second resin mainly provides a restoring force, applying stress to the teeth and promoting tooth movement. The second resin used to form the second resin layer 2 may be any resin as long as it has a restoring force sufficient to apply stress to the teeth and promote tooth movement, and examples of such resins include thermoplastic polyurethane (TPU) and thermoplastic polyester (TPC). It is also preferable that the second resin is non-toxic.

[0088] Next, another embodiment of the method for manufacturing a mouthpiece disc of the present invention will be described. Shown in Figures 6A to 6F is a method for manufacturing a mouthpiece disc, in which a mold 200A consisting of a first mold 201 and a second mold 202 is used to manufacture a mouthpiece disc 100A, and the method is mainly comprised of a first film surface modification step, a third film surface modification step, and a resin supply step.

[0089] The first film surface modification step is a step of performing a physical or chemical surface treatment on the first surface of the first film 11 made of the first resin, which can improve the wettability of the first surface and thereby improve the adhesion between the first surface and the second resin supplied in the resin supply step described below.

[0090] The third film surface modification step is a step of performing a physical or chemical surface treatment on the first surface of the third film 31 having the resin supply holes 31a made of the third resin, which can improve the wettability of the first surface, thereby improving the adhesion between the first surface and the second resin supplied in the resin supply step described below.

[0091] The surface treatments in the first film surface modification process and the third film surface modification process can be any method that improves the adhesion between the first surface of the first film 11 and the second resin, and between the first surface of the third film 31 and the second resin. For example, optical treatment can be used. Optical treatment is a method of modifying the first surface of the first film 11 using an excimer lamp, plasma, or the like. For example, oxygen plasma can be used to form highly hydrophilic functional groups (OH groups) such as carbonyl groups and carboxyl groups on the material surface, thereby chemically improving hydrophilicity. This improves the adhesion and wettability between the first surface of the first film 11 and the second resin, and between the first surface of the third film 31 and the second resin.

[0092] In the resin supplying step, a mold 200A is prepared, which is at least one of a first mold 201 and a second mold 202, and has a recess 230 in a predetermined area that is deeper than the surrounding area. Here, the mold refers to the mold of the present invention described above. Fig. 6A shows a mold having the recess 230 on the first mold 201 side.

[0093] Next, the first film 11 is placed on the inner surface 201a side of a first mold 201 (one of the molds) having a recess 230, and the third film 31 is placed on the inner surface 202a side of a second mold 202, which is the other mold. For example, the first film 11 may be placed on the first mold 201 side, and the third film 31 may be placed on the second mold 202 side by adsorption (see FIG. 6B ). Next, the second mold 202 is placed in the cavity of the first mold 201, leaving a gap between the first film 11 and the third film 31 that is equivalent to the thickness of the second resin layer 2 to be formed (see FIG. 6C ).

[0094] Next, the second resin is supplied under pressure between the first surface of the first film 11 and the first surface of the third film 31 until the thick portion 21 along the recess 230 is formed (see FIG. 6D). The second resin is then cooled and solidified, forming the second resin layer 2 between the first surface of the first film 11 and the first surface of the third film 31. The second mold 202 is then removed from the cavity of the first mold 201 (see FIG. 6E). Finally, the mouthpiece disc 100 is removed from the first mold 201 (see FIG. 6F). The first film 11 becomes the first resin layer 1 of the mouthpiece disc 100A, and the third film 31 becomes the third resin layer 3 of the mouthpiece disc 100A.

[0095] Here, the first film 11 mainly serves to form a shape-retaining portion that maintains the shape of the mouthpiece. Because the mouthpiece is used in the oral cavity, the first resin used for the first film 11 is preferably non-toxic. Specific examples of such resins include glycol-modified polyethylene terephthalate (PETG), glycol-modified polycyclohexylene dimethylene terephthalate (PCTG), and polycarbonate (PC).

[0096] The third film 31 mainly serves to form a shape-retaining portion that maintains the shape of the mouthpiece. Because the mouthpiece is used in the oral cavity, the third resin used for the third film 31 is preferably non-toxic. Specific examples of such resins include glycol-modified polyethylene terephthalate (PETG), glycol-modified polycyclohexylene dimethylene terephthalate (PCTG), and polycarbonate (PC).

[0097] The second resin layer 2 mainly provides a restoring force, applying stress to the teeth to promote tooth movement. The second resin used to form the second resin layer 2 may be any resin as long as it has a restoring force sufficient to apply stress to the teeth and promote tooth movement, and examples of such resins include thermoplastic polyurethane (TPU) and thermoplastic polyester (TPC). It is also preferable that the second resin is non-toxic.

[0098] (Example) Next, an example of a method for manufacturing a mouthpiece disc of the present invention will be described. The mouthpiece disc of this example was manufactured by the following method. First, a 65 mW / cm 2 light source was applied to the surfaces of the first film 11 and the third film 31, each of which was made of glycol-modified polyethylene terephthalate (PETG) and had a thickness of 0.3 mm. ２ The film is then irradiated with light from an excimer lamp for 42 seconds to modify the film (first film surface modification step and third film surface modification step).

[0099] The molds and manufacturing equipment used were those shown in Figures 6A to 6F. The first film 11 was placed in a first mold 201, whose inner surface had a recess 230 deeper than its surrounding area, and the third film 31 was placed in a second mold. Next, a second resin made of thermoplastic polyurethane (TPU) heated to 230°C was supplied under pressure between the first surface of the first film 11 and the first surface of the third film 31 until a thick portion 21 was formed along the recess 230 of the first mold 210 (resin supplying step), followed by injection molding. The second resin layer 22 of the mouthpiece disc 100A manufactured in this manner had a thickness of 0.6 mm in the thick portion and 0.3 mm in the other portions.

[0100] Cross-sectional photographs of the mouthpiece disc of the present invention taken at 400x and 2000x magnifications using a digital microscope are shown in Figures 7A and 7B. As shown in Figures 7A and 7B, the mouthpiece disc of the present invention has no gaps at the bonded surfaces of the resin layers, and is completely bonded. Therefore, the restoring force of the second resin layer 2 can be fully utilized. Furthermore, because there are no gaps, peeling due to the influence of saliva, etc., does not occur, and the restoring force of the second resin layer 2 can be continuously utilized.

[0101] 1: First resin layer 2: Second resin layer 3: Third resin layer 11: First film 21: Thick portion 31: Third film 31a: Resin supply hole 100, 100A: Mouthpiece disc 110: Alignment mark 200, 200A: Mold 201: First mold 202: Second mold 211: First sealing means 212: First intake passage 221: Second sealing means 222: Second intake passage 223: Resin supply flow path 223a: Discharge hole 224: Convex portion 230: Concave portion

Claims

1. A mouthpiece disc comprising a first resin layer made of a first resin and a second resin layer made of a second resin and bonded to the first resin layer, wherein the second resin layer has a thick portion in a predetermined area that is thicker than the surrounding area.

2. The mouthpiece disc according to claim 1, further comprising a third resin layer bonded to said second resin layer on the side opposite to said first resin layer.

3. The mouthpiece disc according to claim 1 or 2, wherein the thick portion has a shape that widens from the center of the mouthpiece disc toward the outer edge.

4. A mouthpiece disc according to claim 1 or 2, characterized in that the thick portion is formed to be thicker than the surrounding area by 0.1 mm to 0.3 mm.

5. The mouthpiece disc according to claim 1 or 2, wherein the second resin has a lower modulus of elasticity than the first resin.

6. The mouthpiece disc according to claim 2, wherein the second resin has a lower modulus of elasticity than the third resin.

7. The mouthpiece disc according to claim 1 or 2, characterized in that at least one of the surfaces of said first resin layer, said second resin layer and said third resin layer has a functional shape with a predetermined function.

8. A mouthpiece molded from the mouthpiece disc of claim 1 or 2, characterized in that the difference in thickness between the occlusal parts of the molars and the occlusal parts of the front teeth is 15% or less of the thickness of the occlusal parts of the molars.

9. A mold for manufacturing a mouthpiece disc, comprising a first mold and a second mold for supplying resin onto a first film to manufacture a mouthpiece disc, wherein the first mold has a first sealing means for sealing the space between the inner surface of the first mold and the outer surface of the first film, and a first air intake passage that penetrates from the outer surface to the inner surface of the first mold, and the inner surface of at least one of the first mold and the second mold has a recess in a predetermined area that is deeper than the surrounding area.

10. A mold for manufacturing a mouthpiece disc, comprising a first mold and a second mold, for supplying resin between a first film and a third film to manufacture a mouthpiece disc, wherein the first mold has: a first sealing means for sealing the gap between the inner surface of the first mold and the outer surface of the first film, and a first air intake passage that passes through from the outer surface to the inner surface; the second mold has a resin supply flow path for supplying the resin through a resin supply hole formed in the third film, a second sealing means for sealing the gap between the inner surface of the second mold and the outer surface of the third film, and a second air intake passage that passes through from the outer surface to the inner surface of the second mold; and the inner surface of at least one of the first and second molds has a recess in a predetermined area that is deeper than its surroundings.

11. A mold for manufacturing a mouthpiece disc as described in claim 9, characterized in that the recess has a shape that widens from the center toward the outer edge of at least one of the first mold and the second mold.

12. A mold for manufacturing a mouthpiece disc as described in claim 10, characterized in that the recess has a shape that widens from the center toward the outer edge of at least one of the first mold and the second mold.

13. A mold for manufacturing a mouthpiece disc as described in claim 10, characterized in that the resin supply flow path has two or more discharge holes arranged at equal angles on the circumference for supplying resin between the first film and the third film.

14. A mold for manufacturing a mouthpiece disc as described in claim 10 or 12, characterized in that the second mold has a convex portion that can fit into a resin supply hole formed in the third film.

15. A mold for manufacturing a mouthpiece disc as described in any one of claims 9 to 13, characterized in that the inner surface of at least one of the first mold and the second mold has an uneven portion for forming a functional shape with a predetermined function on the surface of the mouthpiece disc.

16. A manufacturing apparatus for producing mouthpiece discs, comprising: a mold for manufacturing mouthpiece discs as described in any one of claims 11 to 13; resin supply means for supplying resin into the mold through the resin supply flow path; pressure reducing means for reducing the pressure between the inner surface of the first mold and the outer surface of the first film through a first air intake path; and mold opening / closing means for opening and closing the first and second molds of the mold.

17. A method for manufacturing a mouthpiece disc using a mold consisting of a first mold and a second mold, comprising: a first film surface modification step of applying a physical or chemical surface treatment to a first surface of a first film made of a first resin; and a resin supply step of placing the first film on the inner surface of at least one of the first mold and the second mold, the mold having a recess in a predetermined area that is deeper than its surroundings, and supplying a second resin under pressure to the first surface of the first film until a thick portion is formed along the recess.

18. A method for manufacturing a mouthpiece disc using a mold consisting of a first mold and a second mold, comprising: a first film surface modification step of applying a physical or chemical surface treatment to a first surface of a first film made of a first resin; a third film surface modification step of applying a physical or chemical surface treatment to the first surface of a third film made of a third resin and having a resin supply hole; and a resin supply step of arranging the first film on the inner surface of at least one of the first mold and the second mold, the mold having a recess in a predetermined area that is deeper than its surroundings, and arranging the third film on the inner surface of the other mold, and supplying under pressure a second resin between the first surface of the first film and the first surface of the third film until a thick portion conforming to the recess is formed.

19. A method for manufacturing a mouthpiece disc as described in claim 17 or 18, characterized in that the recess has a shape that widens from the center toward the outer edge of at least one of the first mold and the second mold.

20. A method for manufacturing a mouthpiece disc as described in claim 17 or 18, characterized in that the inner surface of at least one of the first mold and the second mold has an uneven portion for forming a functional shape with a predetermined function on the surface of the mouthpiece disc.

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