JP2022185178A - Manufacturing method of hard type inconspicuous mouthpiece set for correcting tooth row step by step - Google Patents

Abstract

To provide a manufacturing method of a hard type inconspicuous mouthpiece set for correcting a tooth row step by step.SOLUTION: A manufacturing method of a hard type inconspicuous mouthpiece set comprises the steps of: acquiring a digital original tooth row model of a jaw of a patient; arranging an ideal digital setup model on clean check software to define a movement amount and a rotation angle necessary for a tooth in each step; obtaining a plurality of digital step by step tooth row models after calculation by the clean check software; defining a thickness of the surface of the tooth of each digital step by step tooth row model by special software; acquiring a shell-like step-up mouthpiece image; converting the shell-like mouthpiece image into a digital control command; controlling a multiaxial engraving machine; and engraving a plurality of hard type inconspicuous mouthpieces from a polymer hard block by the multiaxial engraving machine.SELECTED DRAWING: Figure 7

Description

The present invention relates to a method for manufacturing a hard-type discreet mouthpiece set for step-by-step orthodontic correction, and in particular, a hard-type discreet mouthpiece set carved with blocks that approximate the hardness of crown enamel. related to the manufacturing method of

The earliest orthodontic methods consisted of tightening and securing an archwire (i.e., steel wire) to brackets bonded to multiple crowns to create stress on the crowns and gradually move the teeth into position. It was to let Referring to FIG. 1, the externally exposed portion of tooth 10 is called crown 11 and the internal portion is called root 12 . The surface of the crown 11 is a layer of very hard enamel 13 . Supporting the tooth 10 is a tooth body 14 made of dentin. The gingiva 15 is attached thereon and the vein 16 , artery 17 and nerve 18 of the tooth enter the pulp 120 via the root canal 19 . Between the main body 14 of the tooth and the alveolar bone 121 is the periodontal ligament 122, between which the ligament 123 extends. The ligament 123 is the critical tissue that anchors the tooth 10 within the alveolus.

When tooth 10 is stressed, ligament 123 is also stressed. The alveolar bone 121 proliferates in the tightened portion of the ligament 123, and the osteoclast absorbs the alveolar bone 121 in the loosened portion of the ligament 123, and the tooth 10 that has been displaced under stress becomes a tension-balanced ligament. The new alveolar is anchored by 123, and other tissues are gradually followed thereafter. This is the principle by which the tooth 10 can be moved and corrected. A method of correcting teeth with brackets and archwires applies the above principle. However, the orthodontic method described above should be used only by an experienced orthodontist who understands the tooth structure, and no problems will arise. It takes an orthodontist a long time to install brackets and archwires.

Briefly, the surface of the tooth where the brackets need to be attached is first etched with a weak acid to roughen it, so that the brackets can be firmly attached, and then the archwire is threaded after the brackets are attached. There are thick, thin, curved, and straight archwires, which makes installation difficult. This makes the patient feel pain and intolerable. The lengthy orthodontic process, calculated over years, requires frequent visits to the dentist's office to have the dentist adjust the brackets and archwires. Furthermore, the oral cavity with brackets and archwires is not only less aesthetically pleasing, but it is also difficult to remove leftover food stuck to the brackets and archwires after meals, making it easy for bacteria to proliferate. It can be easily scratched by rubbing against the skin or tongue. These problems cause long-term inconvenience in life, and patients accept this method to correct their teeth in unavoidable cases.

Recently, discreet mouthpieces have become a new orthodontic option, and in 1997 Align Technology was founded in the United States, promoting discreet mouthpieces under the name Invisalign. The method of correcting is gradually spreading. In addition to Invisalign in the United States, there are very representative brands such as China's Jidai Tenshi and Zhengya, Germany's K Clear, and Japan's AsoAligner. We provide tailor-made and sales services according to individual cases. The manufacturing method of these discreet mouthpieces is similar and small, using a sheet-like soft transparent plastic with uniform thickness as the material, using the 3D printed dentition as the mold, and then heating and vacuuming the mold. Placed in a suction device to form a clear, discreet mouthpiece. The aforementioned method is applied to the processing and molding of many plastic materials and is called the heat suck down method.

A method of correcting teeth with such transparent, discreet mouthpieces was actually described by H. D. It is derived from the step-displacement method proposed by Kesling. His idea was proven by experiments, but according to the dental technology of the time, it took a lot of time and effort to complete a mouthpiece, and mass production was almost impossible. This step-displacement method is so attractive that it is expected that the manufacturing method will continue to be improved and that it will be commercially available, but it has been difficult to realize. After the rapid development of computers and related technologies, Align Technology Inc. was the first to bring the step displacement method to market with the help of computer hardware and software. After Align Technology's patent expired, other brands sprang up like bamboo shoots after the rain. Except for the use of soft transparent plastics with different toughness and thickness, which are independently researched and developed, the heat absorption method is used in the manufacturing process, and the steps are the same. be.

Step 1: Using the patient's digital original dentition model 30 (Fig. 3A), the patient's maxillary dentition 20, mandibular dentition 21 (Fig. 2A), and maxillary dentition 22 (Fig. 2B) obtaining a digital image;
Step 2: Align the digital original dentition model 30 as an ideal digital setup model 31 (Fig. 3B) with Clincheck software;
Step 3: According to the patient's age and dentition and jaw health, define the tooth movement amount, rotation angle and other parameters in each step on the Clincheck software, and calculate the digital original teeth by the Clincheck software. obtaining a plurality of digital step-up dentition models from the row model 30 to the digital setup model 31;
Step 4: Using a 3D printer, print each step-up physical impression 41 using light-curing resin according to each digital step-up dentition model;
Step 5: Take a vacuum thermoformed plastic sheet 40, heat it and press it against a physical tooth mold 41 as a model (Fig. 4A) and let it form using strong vacuum suction while pressing; After cooling, the sheet 42 with the tooth impression (FIG. 4B) is removed and then a hot knife or sharp scissors is used to remove the sapwood from the machined sheet 42 along the gingival line to create a soft, discreet mouthpiece. obtaining 43 (Fig. 4C);
Step 6: For other digital step-up dentition models, each soft type inconspicuous mouthpiece 43 is formed one after another according to step 5 to complete the mouthpiece required for orthodontic treatment.

The soft discreet mouthpiece 43 made of vacuum thermoformed plastic material has a smoother surface that is softer than tooth enamel, so the retention force of the soft discreet mouthpiece 43 against the teeth is increased. ) is insufficient, and the frictional force between the soft type inconspicuous mouthpiece 43 and the teeth is also insufficient. I can't go to

Since the retention force of the soft type discreet mouthpiece 43 is insufficient, the soft type discreet mouthpiece 43 may fall off after being worn for several days. To solve the aforementioned problems, Aligner Technology first professes to use elements called attachments or potches, which are glued to the teeth to enhance their orthodontic ability. However, the technique of adhering the attachment to the tooth is not easy. First, it is necessary to place attachment images 50 (FIG. 5A) of different shapes on the digital original dentition model 30 before aligning the teeth. When the 3D printing of each physical tooth mold is completed, the attachment model is already on top of the tooth mold, so you can see protrusions on the outside of each completed mouthpiece from now on, and when viewed from the inside, it is the groove of the attachment shape. be. To ensure good adhesion of the physical attachment to the tooth, the dentist first acidifies and cleans the tooth surface. Next, light-curable epoxy resin is applied to each groove on the 0-step mouthpiece, the mouthpiece is attached, and the epoxy resin is light-cured. are left on the teeth (Fig. 5B) so that the patient can start the step-by-step orthodontic treatment with the one-step mouthpiece.

U.S. Patent Application Publication No. 2008/0254402A1 U.S. Patent Application Publication No. 2006/0093982A1

This kind of soft type mouthpiece needs to be worn for at least 22 hours a day, and the mouthpiece is removed only when eating and brushing teeth. If an attachment loosens and falls when force is applied to remove the mouthpiece, it may be necessary to seek the assistance of a dentist to reattach the attachment.

A soft type mouthpiece is smooth and lacks hardness, so the frictional force between the mouthpiece and teeth is insufficient. In addition, since the mouthpiece is formed by first heating the plastic and then strongly sucking it with a vacuum, the thickness of the mouthpiece is uneven, and the mouthpiece is always stuck between the teeth. Due to the arcuate shape, the covering surface of the mouthpiece against the teeth is reduced, and the orthodontic stress is also reduced. For these reasons, it is almost impossible to correct multiple root molars with soft type mouthpieces.

Soft-type discreet mouthpieces have been very successful in correcting incisors, but for other single-rooted teeth such as canines and premolars, the correction is often not as expected, so it is necessary to use intraoral mouthpieces during correction. Scanning, aligning, 3D printing, and having to re-create a new set of mouthpieces lengthens orthodontic time and reduces patient patience. For this reason, some manufacturers offer a free service as compensation when remaking a new set of mouthpieces.

In addition, the raw material of the 3D printed physical tooth mold is light-curing epoxy resin, which cannot be recycled and becomes waste once used. More step-up mouthpieces mean more waste. Soft, discreet mouthpieces pose unavoidable environmental concerns.

In addition to the method of manufacturing the mouthpiece with vacuum thermoforming plastic material, US Pat. is. In Patent Document 2, after taking a dental arch model, a mouthpiece model is manufactured by CNC, then this mouthpiece model is disassembled into several elements, further mouthpiece elements are manufactured by CNC, and finally Reconnect the mouthpiece element as an orthodontic mouthpiece. However, this method is too cumbersome, loses stress at the reconnection point of the mouthpiece element, and cannot effectively correct teeth.

Focusing on this, it is possible to effectively improve the deficiencies of the above-mentioned inconspicuous mouthpiece (soft type mouthpiece) such as exemption from troublesome and unpredictable attachment work, How to make the corrective effect of the inconspicuous mouthpiece (soft type mouthpiece) completely as expected by strengthening the holding power and friction of the mouthpiece model and reducing the waste of the mouthpiece model. This is an important problem that current orthodontic providers want to improve, and it is also the problem that the present invention seeks to solve.

Focusing on the fact that conventional soft-type mouthpieces still have defects, after repeated research and experiments, we developed a manufacturing method for a hard-type, discreet mouthpiece set that corrects the dentition step-by-step. It is required to effectively solve the problems of

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a hard type discreet mouthpiece set for correcting dentition step by step. The manufacturing method scans and constructs digital images of proper occlusion of the patient's maxillary, mandibular, and mandibular dentition as digital original dentition models, respectively; After reading the digital original dentition model, arranging the ideal digital setup models respectively, defining the movement amount and rotation angle required for the teeth in each step, and calculating by Clincheck software, each of the digital original dentition Obtaining a plurality of digital step-by-step dentition models from the model to the digital set-up model; and calculating the tooth surface thickness of each of the digital step-by-step dentition models and each of the digital set-up models with special software, respectively. define and obtain a shell-like mouthpiece image; finally, convert each said shell-like mouthpiece image into respective digital control commands, thereby controlling a multi-axis engraving machine to perform a plurality of steps from a polymer rigid block. Engrave the up mouthpiece to form a hard type discreet mouthpiece set. With such a manufacturing method of the present invention, the hard type inconspicuous mouthpiece set can be rapidly manufactured, and the patient only needs to wear each step-up mouthpiece on his/her teeth according to a pre-planned period. , the effect of orthodontics can be exhibited.

In order to further appreciate and understand the technical features and effects of the objects of the present invention, a detailed description will be given below with reference to embodiments and the accompanying drawings.

It is a schematic diagram which shows the structure of a tooth. It is a schematic diagram which shows a patient's original maxillary dentition and mandibular dentition. FIG. 4 is a schematic diagram showing a proper occlusion of the patient's original maxillary and maxillary dentition. FIG. 4 is a schematic diagram showing a digital original dentition model; FIG. 10 is a diagram showing a digital setup model; 1 is a schematic diagram showing a vacuum formed plastic sheet and a physical tooth impression; FIG. 1 is a schematic diagram showing a sheet after vacuum forming plastic sheet forming; FIG. FIG. 3 is a schematic diagram showing a soft type discreet mouthpiece. It is a figure which shows an attachment image at the time of attaching an attachment. 1 is a schematic diagram showing a tooth with a clinical physical attachment; FIG. It is a schematic diagram which shows a hard block. FIG. 4 is a schematic diagram showing a block with completed engraving; It is a schematic diagram which shows a step-up mouthpiece. It is a flow chart of the manufacturing method of the present invention. FIG. 10 is a diagram showing how the top of a hard type inconspicuous mouthpiece is hollowed out. FIG. 10 is a diagram showing a hard type inconspicuous mouthpiece provided with physical tooth positions. It is a schematic diagram showing a short type mouthpiece.

In order to make the purpose, technical content and advantages of the present invention clearer, the following will refer to the accompanying drawings together with the specific embodiments to correct the dentition step by step disclosed in the present invention. An embodiment of "Method for manufacturing a hard type inconspicuous mouthpiece set" will be described in further detail. A person skilled in the art can understand the advantages and effects of the present invention from the contents disclosed herein, and the present invention can be implemented or applied through other different specific embodiments. Various modifications and changes can be made to the details in this specification based on different viewpoints and applications without departing from the technical spirit of the present invention. It should be noted in advance that the drawings of the present invention are merely schematic diagrams and are not drawn to scale. The following embodiments describe the technical content related to the present invention in more detail, but the disclosed content is not intended to limit the protection scope of the present invention.

Based on many years of experience in the design and manufacture of CNC multi-axis engraving machines for engraving dental products such as dentures, night guards, etc., the inventor engraves dentures under the requirements and guidance of orthodontists. A hard PMMA block 60 (Fig. 6A) is selected as the material for mouthpiece engraving, and the mouthpiece is engraved, manufactured, improved and tested repeatedly. A mouthpiece (ie, step-up mouthpiece 62, referred to in subsequent examples) was completed. It should be noted that in the manufacturing method of the present invention, it is not necessary to first print a physical tooth mold by 3D printing technology.

Generally speaking, a patient's panoramic radiograph (commonly known as a "pano film") to determine dental health, whether it is a soft or hard discreet mouthpiece. ) must be obtained first. Unhealthy teeth are treated first, and artificial tooth roots such as implants cannot be moved. Compared to the soft type mouthpiece manufacturing process, the manufacturing process of the hard type discreet mouthpiece of the present invention eliminates the troublesome procedure of attaching attachments, and prints all physical teeth in 3D in advance. No need to mold the mouthpiece with a vacuum thermoforming machine, no need to remove the sapwood with a multi-axis engraver. The manufacturing method of the present invention is as follows. See FIG.

Step (801): Scan the patient's dentition with 3D scanning technology (e.g., a 3D laser intraoral scanner) to determine the proper alignment of the patient's maxillary dentition 20, mandibular dentition 21 (FIG. 2A), and mandibular and mandibular dentition. Acquiring a digital image of the occlusion pattern 22 (FIG. 2B) as a digital original dentition model 30 (FIG. 3A) of the patient;
Step (802): Read each said digital original dentition model with Clincheck software, and arrange each said digital original dentition model 30 as an ideal digital setup model 31 (Fig. 3B);
Step (803): According to the patient's age and dentition and jaw condition, define the tooth movement amount, rotation angle and other parameters in each step on the Clincheck software. obtaining a plurality of digital step-by-step dentition models from the original dentition model 30 to the digital setup model 31;
Step (804): Use special software (e.g. CAD software) to set the thickness of each surface on the tooth surface of each digital step-by-step dentition model corresponding to the upper and lower dentition to form the shell of each step-up mouthpiece. forming a shaped mouthpiece image;
Step (805): The CAM software converts the shell-shaped mouthpiece image of the step-up mouthpiece into a digital control command (e.g., NC code) that can be read by the digital engraving machine, and sends it to the controller of the digital engraving machine. , put the hard PMMA block 60 (FIG. 6A) into the digital engraving machine, let the digital engraving machine perform the engraving of the mouthpiece, take out the engraving block 61 (FIG. 6B) when the engraving is completed, cut out the mouthpiece, After microfabrication and finishing, a pair of step-up mouthpieces 62 (FIG. 6C) are completed;
Step (806): By repeating step (805), another step-up mouthpiece 62 is completed to form a hard type discreet mouthpiece set.

All the software required for the above steps is commercially available. 3D laser intraoral scanners used in step (801) include Trios from 3shape, Omnicam from Sirona, CS3600 from Carestream; Clincheck software includes 3shape Ortho Analyzer, INTEWARE Ortho Analysis, exocad Ortho, etc.; CAD software used in step (804) includes 3shape Ortho System, Dental CAD manufactured by exocad, EZCAD manufactured by INTEWARE, iOtho manufactured by angelalign, etc.; EZCAM manufactured by the company.

The multi-axis engraving machine used in the above steps is a temporary denture engraving machine manufactured by ARIX CNC MACHINES CO., LTD., with an accuracy of ±20 μm. be. The rigid PMMA block 60 used is manufactured by YAMAHACHI DENTAL MFG. , CO's factory in Wuxi, China, with a hardness ranging from 75 to 85 Shore hardness, close to the hardness of crown enamel, and toughness to prevent fragmentation.

Summarizing the above, the manufacturing method of the present invention can have the following features and effects. First of all, PMMA is an abbreviation of Poly (Methyl MethylAcrylate), which is polymethyl methacrylate in Japanese, also called organic glass, is a long-chain polymer, and this kind of organic glass is broken into fragments even after being hit by a bullet. It does not shatter, can be used as bulletproof glass, has the advantages of high transparency, low price, easy machining, etc. It is a medical grade material, a hard material with toughness, and does not lose its hardness. , the retention force can be maintained at all times, and engraving on the hard-type discreet mouthpiece (step-up mouthpiece 62) avoids the frustration and inconvenience of gluing the potch to the tooth.

Next, when making a hard-type inconspicuous mouthpiece using the engraving method, by engraving the inner surface with a rough surface, the frictional force of the hard-type inconspicuous mouthpiece against the crown can be greatly increased, resulting in hardness. In addition to having a sufficient mouthpiece, the hard type discreet mouthpiece allows the molars to be easily moved, and all teeth can be corrected. A well-chewed food not only reduces the burden on the digestive system, but also allows better digestion and absorption, making the body healthier.

Furthermore, when manufacturing a hard type inconspicuous mouthpiece by engraving, it is possible to define the thickness between each position of the hard type inconspicuous mouthpiece and the tooth mold on computer software (special software). Since the engraving machine engraves according to the command, a hard type discreet mouthpiece can be engraved into fins between each tooth. The fins are sandwiched between the teeth when a hard type inconspicuous mouthpiece is worn, ensuring the holding force of the mouthpiece against the teeth, making it difficult to fall off, and at the same time, the overall area of the teeth is larger. The force applied to each tooth crown from the hard type discreet mouthpiece is planar and the stress is uniform, which prevents the movement of the root of the tooth. Parallel to the movement of the crown, allowing movement of the whole tooth. According to the biomechanics of teeth, if the applied force is not uniform, the root and crown can move in opposite directions, which risks dislodging the root from the alveolar bone.

Since the fins in the interproximal part ensure a holding force, and the PMMA block 60 is selected as the material for the hard type inconspicuous mouthpiece carving, it is possible to wear the hard type inconspicuous mouthpiece (step-up mouthpiece 62) during the wearing period. The holding power of the hard discreet mouthpiece is not reduced, adding to the frictional forces caused by the rough inner surface of the hard discreet mouthpiece, and increasing the effectiveness of each hard discreet mouthpiece (i.e., the step-up mouthpiece 62). ) movement of teeth, including molars, is as expected, so simply reporting the current state of wearing to the dentist at a remote location, the mouthpiece can be replaced regularly if there are no abnormalities, so dental care can be performed during the orthodontic period No need to go to the hospital. This is particularly convenient for patients in remote areas or those who travel long distances for business or travel.

A recent study points out that it is most appropriate to correct a child's teeth during the mixed dentition period of the child when the baby teeth are replaced by the permanent teeth. If the growth rate of a particular permanent tooth is very fast, the top of the hard-type discreet mouthpiece (step-up mouthpiece 62) on the occlusal surface of this tooth is hollowed out (i.e., enclosed by the dashed circle in FIG. 8A). By forming openings 70 such as pits, the teeth are free to grow unimpeded. This is something that cannot be achieved when conventional soft type mouthpieces are manufactured, and the method of hollowing out the mating surfaces of the mouthpiece is also suitable in other cases, if desired. In addition, if the adult's dentition is abnormal before implanting artificial teeth after the teeth have fallen out, if possible, the teeth should be corrected first. At this time, the hard type inconspicuous mouthpiece (step-up mouthpiece 62) is placed at this tooth position (that is, the missing tooth) at the physical tooth position 71 (the place surrounded by the dashed circle in FIG. 8B). and supports two adjacent teeth without tilting inwards. Without the physical tooth position 71, the mouthpiece (step-up mouthpiece 62) cannot correct the teeth. This is also not possible when soft type mouthpieces are manufactured.

If the patient has only a few teeth to be corrected, the holding force and friction force of the hard type discreet mouthpiece are strong enough, so if the nearby teeth are strong and can be used as a fixation source, the short type mouthpiece 72 is used. can be engraved on For example, if the patient needs to straighten only the central incisors, only the short type mouthpiece 72 with hollowed out upper central incisors and canines can be used, using the premolars and canines as anchoring sources during the correction. That is, the short type mouthpiece 72 does not fully correspond to the total number of teeth of the patient's maxillary or mandibular dentition, but is less than the number of teeth of the maxillary or mandibular dentition, and the short type mouthpiece 72 is more comfortable for the patient to wear.

Finally, there is no need to use 3D-printed physical impressions to manufacture mouthpieces by engraving, no need to use plastic vacuum thermoforming machines, and large quantities of disposable physical impressions. No waste is generated, and scraps and sapwood cut out from PMMA are recyclable because there is no material change due to chemical action, so there is no problem of environmental conservation.

Although the above are only preferred embodiments of the present invention, the scope of rights claimed by the present invention is not limited thereto. Of course, variations within various equivalent ranges that can be easily conceived by those skilled in the art based on the technical content disclosed in the present invention are equally included in the protection scope of the present invention.

10 Tooth 11 Crown 12 Root 120 Pulp 121 Alveolar bone 122 Periodontal ligament 123 Ligament 13 Enamel 14 Main body of tooth 15 Gingiva 16 Vein 17 Artery 18 Tooth nerve 19 Root canal 20 Maxillary dentition 21 Mandibular dentition 22 Upper and lower dentition 30 Digital original dentition model 31 Digital setup model 40 Vacuum thermoformed plastic sheet 41 Physical impression 42 Sheet 43 Soft discreet mouthpiece 50 Attachment image 51 Clinical physical attachment 60 PMMA Block 61 Engraved block 62 Step-up mouthpiece 70 Opening 71 Physical tooth position 72 Short type mouthpiece 801-806 Steps

Claims (5)

Acquiring digital images of proper occlusion of the patient's maxillary dentition, mandibular dentition, and mandibular dentition using 3D scanning technology as digital original dentition models, respectively;
Read each of the digital original dentition models with the Clincheck software, arrange the ideal digital setup models, define the movement amount and rotation angle required for the teeth in each step, and calculate by the Clincheck software. obtaining a plurality of digital step-by-step dentition models from said digital original dentition model to said digital setup model;
Defining the tooth surface thickness of each of the digital step-by-step dentition models and each of the digital set-up models in specialized software, respectively, to acquire shell-like mouthpiece images;
Each shell-shaped mouthpiece image is converted into a digital control command to control a multi-axis engraving machine, and the multi-axis engraving machine engraves a plurality of step-up mouthpieces from a polymer hard block to form a hard type. forming a discreet mouthpiece set;
A manufacturing method for a hard type inconspicuous mouthpiece set for correcting dentition step by step. 2. The manufacturing method according to claim 1, wherein the polymeric hard block material is polymethyl methacrylate. 2. The method of claim 1, wherein at least one localized location on the step-up mouthpiece is hollowed out depending on the patient's condition. The manufacturing method according to claim 1, wherein at least one physical tooth position is left in the step-up mouthpiece according to the patient's condition. 2. The step-up mouthpiece according to claim 1, wherein the step-up mouthpiece is carved to have fewer teeth than the patient's maxillary dentition or mandibular dentition to form a short type mouthpiece. Production method.

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