Maxillary movable appliance in the period of tooth replacement and manufacturing method thereof

Abstract

The present invention provides a removable maxillary appliance for the replacement period and a method for manufacturing the same, belonging to the technical field of medical devices. The removable appliance comprises a retaining member, a torsion force member, and an arch expansion force member. The arch expansion force member is disposed between and connects the left and right base portions of the retaining member. The torsion force member is a pair of force couples that apply a torque in the same direction to the twisted teeth to straighten them, and comprises a tension force member and a thrust force member. The removable appliance combines arch expansion correction with orthodontic correction of twisted teeth, straightening the twisted teeth while expanding the arch, thereby overcoming the drawbacks of existing correction schemes, such as the long treatment time, which misses the optimal period for correcting twisted teeth during the replacement period, and the tendency to damage the patient's teeth.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices and relates to a removable appliance used in the field of oral medicine, and in particular to a maxillary removable appliance for the dentition replacement period and a manufacturing method thereof. Background Art

[0002] In the clinical work of the oral orthodontics department, malocclusion in children is a phenomenon in which the erupted front teeth of children in the dentition replacement period are twisted due to early loss or retention of deciduous teeth. If not corrected in time, this type of malocclusion will not only affect the appearance of the child, but may also cause occlusal trauma (due to the failure to establish a good occlusal relationship between the teeth opposite the twisted teeth), and affect the normal cutting function of the front teeth; even the erupted adjacent teeth will occupy the space of the twisted teeth, causing crowding of the teeth, which increases the difficulty of orthodontic treatment during the constant pressure period. For cases that can be treated with non-extraction treatment, extraction treatment will eventually be required to solve the problem of crowded teeth.

[0003] Patients with malocclusion and crowded dentition are mostly caused by the disharmony between the amount of teeth and the amount of bone, especially the varying degrees of arch stenosis in the upper and lower dental arches, and bilateral arch stenosis is also relatively common. Clinically, tooth extraction is usually used to obtain space to solve the problem of crowded dentition, but for mild crowding, arch expansion can be used to obtain a small amount of space to align the teeth. Maxillary arch expansion can effectively expand the dental arch, so that the increase in crown width is greater than the buccal inclination of the crown, thereby increasing the arch circumference and alleviating the problems of crowded dentition and arch stenosis. For children in the growth and development period, the mid-palatal suture can be opened by applying a lateral orthopedic force. As the mid-palatal suture widens, new bone will be formed in between, and the maxillary bone will be widened by bone deposition, providing sufficient bone volume to align the upper and lower teeth.

[0004] At present, for the correction of twisted anterior teeth during the tooth replacement period, non-orthodontic doctors recommend full-mouth fixed treatment after all teeth are replaced. However, this treatment plan misses the opportunity for early correction to stimulate maxillary bone development, and also causes severe crowding of the maxillary dentition due to the narrow maxillary dental arch. It not only increases the probability of tooth extraction, but in severe cases, the patient needs to undergo orthodontic combined with surgical treatment to correct facial beauty and tooth occlusion in adulthood. Some pediatricians also propose separate treatment plans for children with twisted upper anterior teeth and narrow upper dental arches during the tooth replacement period, that is, first expand the arch and then correct the twisted teeth. This treatment plan prolongs the treatment time because the eruption of the adjacent teeth occupies the position of the twisted teeth, which may miss the best time to correct the twisted teeth during the tooth replacement period, aggravates the crowding of the teeth, and increases the difficulty of subsequent correction of the twisted teeth.

[0005] In order to deal with the twisting of the anterior teeth during the period of replacement dentition, the "2×4" correction technique is currently used in orthodontic clinics. Figure 1, that is, the two first permanent molars are bonded with bands or buccal tubes 10, and the four incisors are bonded with retention brackets 20 (the retention brackets are straight wire brackets), and nickel-titanium round wire is used as the correction arch wire 30. The two ends of the correction arch wire are fixed on the bands or buccal tubes 10, and the middle part is embedded in the retention bracket 20 for fixation. This correction technology is a fixed orthodontic appliance that can be used to relieve crowding of anterior teeth and individual tooth twisting. This correction method has high requirements on the patient's oral hygiene and is prone to cause oral ulcers. In addition, the correction arch wire 30 applies force to multiple anterior teeth, which inevitably affects or damages these teeth; especially for the apical foramen of the teeth that have just been replaced and are not completely closed, the correction arch wire is prone to apply too much force to the twisted teeth, and the children need to bear the correction risks of apical resorption, loose teeth, etc. Summary of the Invention

[0006] In order to correct the twisted front teeth during the dentition replacement period, ensure the normal eruption of the adjacent teeth of the twisted teeth, simplify the treatment course of fixed orthodontic treatment during the dentition replacement period, and relieve the problems of dentition crowding and dental arch narrowing, the present invention provides a maxillary removable orthodontic appliance for the dentition replacement period.

[0007] The above objectives are achieved by the following technical solutions:

[0008] A maxillary removable appliance for the period of tooth replacement, comprising a retaining member, a twisting force member and an arch expansion force member, wherein:

[0009] The retaining member is used to connect the teeth on both sides together to form a tooth anchorage, including a base covering the upper jaw and the palatal side of the dentition, an occlusal pad covering the occlusal surface of the dentition on both sides, a hyperbolic lip bow (15) wrapping the labial crown of the anterior teeth, and a plurality of retaining clasps (16) clamped on the teeth on both sides, the base including a left base part and a right base part, the occlusal pad including a left occlusal pad and a right occlusal pad, the left occlusal pad and the left base part are integrally formed, and the right occlusal pad and the right base part are integrally formed, the two curved ends of the hyperbolic lip bow (15) are respectively fixedly embedded in the left base part and the right base part, and each retaining clasp (16) is respectively fixed on the base;

[0010] The torsion force applying member comprises a tension-type force applying member (21) and a thrust-type force applying member (22) respectively connected to the base, the tension-type force applying member (21) is arranged on the labial side of the torsion tooth, and the thrust-type force applying member (22) is arranged on the palatal side of the torsion tooth. The tension-type force applying member and the thrust-type force applying member simultaneously apply torque in the same direction to the torsion tooth to make the torsion tooth turn straight, and the force application points of the two are arranged at the same height in the middle of the torsion tooth to form a pair of force couples;

[0011] The expansion force applying member (4) is arranged between the left base part and the right base part and connects the left base part and the right base part, and is used to apply an outward thrust to the base parts on both sides.

[0012] In the above-mentioned maxillary removable appliance for the dentition replacement period, the tension-type force-applying member (21) comprises:

[0013] A bracket (211) is used for fixing to the middle part of the crown on the labial side of the twisted tooth;

[0014] A traction hook (212) is provided at the tooth gap on the side opposite to the torsion direction of the torsion tooth, the hook portion of the traction hook is located on the lip side, and the tail portion is embedded in the base; and

[0015] The elastic member (213) has one end connected to the draw hook of the bracket (211) and the other end connected to the hook portion of the traction hook, and the stretching direction of the elastic member is consistent with the long axis direction of the torsion tooth; the elastic member (213) is preferably a rubber chain.

[0016] In the above-mentioned maxillary removable orthodontic appliance for the tooth replacement period, the thrust-type force-applying member (22) is a multi-curved spring, which is arranged on the palatal side of the twisted tooth, with one end buried in the base and the other end abutting against the palatal side of the twisted tooth, for applying a thrust to the twisted tooth in the opposite direction of its twisting direction.

[0017] In the above-mentioned maxillary removable orthodontic appliance for the replacement period, the multi-curve spring is a sinusoidal or cosine-shaped multi-curve structure made of stainless steel round wire, one end of which is buried in the base as a fixed end, and the other end is a free end used to abut against the twisted tooth, and there are multiple parabolic curves connected in sequence between the two ends.

[0018] In the above-mentioned maxillary removable orthodontic appliance for the dentition replacement period, the force application direction of the multi-curved spring is opposite to the torsion direction of the twisted tooth, and the height of the force application point is 1 / 2 of the crown height of the twisted tooth.

[0019] In the above-mentioned maxillary removable appliance for the edentulous period, the retaining clasp (16) is an arrowhead clasp and / or a single-arm clasp.

[0020] In the above-mentioned maxillary removable orthodontic appliance for the edentulous period, the expansion force member (4) includes a left retaining portion, a right retaining portion and a spiral force applying portion, the spiral force applying portion is located between the left retaining portion and the right retaining portion and connects the left retaining portion and the right retaining portion; the left retaining portion and the right retaining portion are respectively embedded in the left base portion and the right base portion.

[0021] In the above-mentioned maxillary removable orthodontic appliance for the replacement dentition period, the spiral force-applying part is welded to the left retaining part and the right retaining part respectively, the spiral force-applying part is provided with a spiral hole and a force-applying key, a preset force-applying direction mark is provided on the left retaining part or the right retaining part, and the force-applying key is used to insert into the spiral hole and rotate to apply force in the predetermined force direction.

[0022] In the above-mentioned maxillary removable orthodontic appliance for the dentition replacement period, in order to address the situation where the adjacent teeth of the twisted tooth have not erupted and a gap (02) between the adjacent teeth of the twisted tooth appears, the twist force-applying member further includes a limiting clasp (23), the limiting clasp (23) is a single-arm clasp formed by bending the arch wire, and is arranged at the missing tooth gap (02) of the twisted tooth, the arm end of which is buried in the base, and the curved end extends from the missing tooth gap to the labial side and surrounds the labial crown of the twisted tooth.

[0023] The present invention also provides a method for manufacturing the above-mentioned maxillary removable appliance for the edentulous period, comprising the following steps:

[0024] 1) Prepare a maxillary plaster model based on the patient's oral and maxillary condition;

[0025] 2) Apply a layer of separating agent on the dried maxillary plaster model, place the bent hyperbolic labial bow, retention clasp and traction hook in the predetermined position in sequence, and temporarily fix them with wax drops; squeeze the parabolic curve of the bent multi-curved spring close to the free end according to the predetermined thrust and seal it with wax drops, then use a wax seat to raise the multi-curved spring to place it in the predetermined position; fill the spiral hole of the expansion force member, and fix the bottom of the expansion force member to the middle of the maxilla with wax, and vertically set a spacer of a certain thickness in the base area of ​​the middle of the maxilla to form a middle disconnection seam between the left base part and the right base part; finally, fill the base area and occlusal pad area of ​​the maxillary plaster model with the prepared self-setting material, and after the self-setting material solidifies, form an integrated base and occlusal pad with a middle disconnection, and at the same time, the base fixes the hyperbolic labial bow, retention clasp, traction hook, multi-curved spring and expansion force member;

[0026] 3) Remove the spacer from the above model and demould it, and fix the bracket on the predetermined position of the patient's twisted tooth. According to the positional relationship between the traction hook and the bracket, select a suitable elastic member so that the twisting force meets the predetermined requirements.

[0027] By adopting the above technical means, the present invention has the following technical effects:

[0028] 1) The orthodontic appliance of the present invention sets the force application points of the thrust-type force-applying member on the palatal side and the tension-type force-applying member on the labial side at the same height in the middle of the twisted tooth. The thrust of the thrust-type force-applying member on the twisted tooth and the tension of the tension-type force-applying member on the twisted tooth form a pair of force couples, which helps to straighten the twisted tooth and allows the correction force to pass through the resistance center of the tooth, avoiding damage to the tooth caused by depression or extension, and facilitating the normal eruption of adjacent teeth or secondary correction.

[0029] 2) The multi-curve spring is used as a thrust-type force-applying member. The thrust it applies is a light force that is released slowly, which will not apply excessive correction force to the torsion tooth. At the same time, it plays an auxiliary role in controlling the force direction of the torsion tooth. The thrust applied to the torsion tooth can be adjusted by adjusting the curvature value of the parabolic curve of the multi-curve spring, which is convenient and flexible to adjust.

[0030] 3) By setting up a hyperbolic labial arch in the anterior tooth area, it not only serves as a retention mechanism but also limits the position of the twisted teeth, preventing them from tilting excessively toward the labial side during correction.

[0031] 4) By placing the base on the palate, and the occlusal pad on the occlusal surface of the teeth in the molar area or the occlusal surface of the teeth in the molar area and canine area, the occlusal interference of the upper and lower jaws is eliminated. After the patient wears the braces, the base and occlusal pad are not visible when speaking normally or opening the mouth, which does not affect the beauty of the teeth. The retaining parts use the teeth in the molar area and canine area as a whole as support, which can achieve good retention and make the braces balanced and stable in the mouth.

[0032] 5) This appliance is a removable appliance, with brackets bonded only to the twisted teeth. Other components are embedded in the base, making it easy to remove, which is beneficial for maintaining oral hygiene. It also facilitates the replacement of elastic components and adjustment of the curvature of the multi-curved spring to achieve better correction results. The correction force of the twisting force-applying component only acts on the twisted teeth, with little impact or damage to other teeth, thus reducing the incidence of ulcers in patients. This appliance is suitable for children who have just had their teeth replaced.

[0033] 6) For anterior teeth with relatively large twisting, a limiting clasp is installed in the edentulous space. One end of the limiting clasp is embedded in the base, and the other end extends from the edentulous space to the labial side and surrounds the labial crown of the twisted tooth, thus limiting the twisted tooth and preventing it from tilting toward the edentulous space.

[0034] 7) For cases of crowded dentition and narrow dental arches, an arch expansion force piece is installed in the middle of the maxilla to transmit the correction force through the base to the teeth acted on by the retainer, thereby opening the mid-palatal suture and widening the maxillary bone, which can also relieve the problems of crowded dentition and narrow dental arches.

[0035] The removable orthodontic appliance of the present invention follows the orthodontic concept of "discovery is intervention". It uses an occlusal pad to open the bite, and then uses the maxillary arch expansion force member to expand the upper dental arch while using the twisting force member to straighten the twisted teeth, thereby shortening the correction time and facilitating the growth of the maxillary bone. For patients with narrow dental arches and crowding during the replacement dentition period, it reduces the chance of later tooth extraction or orthognathic surgery, and is conducive to the formation of a normal soft and hard tissue profile. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the structure of the existing "2×4" appliance;

[0037] Figure 2A 1 is a schematic structural diagram of a first embodiment of a removable orthodontic appliance according to the present invention (viewed from above);

[0038] Figure 2B yes Figure 2A A magnified schematic diagram of area A in the middle;

[0039] Figure 2C yes Figure 2A Schematic diagram of the structure of the removable appliance from another perspective (seen from the labial side);

[0040] Figure 3 It is a structural diagram of a bent multi-curve spring;

[0041] Figure 4A This is a schematic structural diagram of a second embodiment of the movable orthodontic appliance of the present invention;

[0042] Figure 4B yes Figure 4A Enlarged schematic diagram of middle area B;

[0043] Figure 5 It is a structural diagram of the expansion force member.

[0044] The reference numerals in the figures are as follows:

[0045] 10-buccal tube, 20-retaining bracket, 30-correction archwire;

[0046] 01-Twisted teeth; 02-Gap between missing teeth;

[0047] 1-retainer, 11-left base, 12-right base, 13-left occlusal pad, 14-right occlusal pad, 15-hypercurved labial bow, 16-retention clasp;

[0048] 2-torsion force member, 21-tension force member, 211-bracket, 212-traction hook, 213-elastic member; 22-thrust force member; 23-limiting clamp;

[0049] 3-multi-bend spring, 31-fixed end, 32-parabolic bend, 33-free end;

[0050] 4- expansion force member, 41- left retaining part, 42- right retaining part, 43- spiral force applying part, 44- spiral hole, 45- preset force direction mark, 46- force key. DETAILED DESCRIPTION

[0051] For patients with twisted front teeth and narrow upper dental arches during the tooth replacement period, clinicians usually recommend expanding the arch first and then correcting the twisted teeth. This separate correction plan takes a long time, and time is needed to maintain the stability of the expansion effect after arch expansion. The erupted adjacent teeth may occupy the space of the twisted teeth, and subsequent correction of the twisted teeth also requires expanding the space, which is relatively complicated to implement. In addition, orthodontic correction clinically generally uses fixed appliances based on the "2×4" correction technology. This appliance has high requirements on the patient's oral hygiene and a strong foreign body sensation. Especially for the apical foramen of the newly replaced teeth that is not completely closed, the correction arch wire may easily exert excessive force on the twisted teeth, and the children need to bear the risks of correction such as apical resorption and loose teeth.

[0052] In response to the above problems, the present invention provides a maxillary removable orthodontic appliance for the edentulous period and a method for manufacturing the same. The removable orthodontic appliance combines arch expansion correction and tooth twisting orthodontic correction together, correcting twisted teeth while expanding the arch, thereby overcoming the defects of existing correction schemes such as long treatment time and easy impact or damage to the teeth of children.

[0053] The movable orthodontic appliance of the present invention comprises a retaining member, a torsion force applying member and an arch expansion force applying member, wherein:

[0054] The retainer includes a base covering the upper jaw and the palatal side of the dentition, an occlusal pad covering the occlusal surfaces of both dentitions, a hyperbolic labial arch wrapping the labial crowns of the anterior teeth, and multiple retaining clasps secured to the teeth on both sides. The base includes a left base portion and a right base portion, and the occlusal pad includes a left occlusal pad and a right occlusal pad. The left occlusal pad is integrally connected to the left base portion, and the right occlusal pad is integrally connected to the right base portion. The two curved ends of the hyperbolic labial arch are fixedly embedded in the left and right base portions, respectively, and the retaining clasps are respectively secured to the base. The retainer connects the dentitions on both sides to form a tooth anchorage.

[0055] The torsion force-applying member of the orthodontic appliance is a pair of force-applying couples used to apply force to the twisted tooth, including a tension-type force-applying member and a thrust-type force-applying member. The tension-type force-applying member is formed by a bracket fixed on the labial side of the twisted tooth, a traction hook embedded in the base at the tail, and an elastic member with the distal wing and traction hook respectively hung on the bracket at both ends. The thrust-type force-applying member is formed by a multi-curved spring located on the palatal side of the twisted tooth, one end of the multi-curved spring is embedded in the base, and the other end abuts against the twisted tooth. The tension-type force-applying member and the thrust-type force-applying member apply a torque in the same torsional direction to the twisted tooth to straighten the twisted tooth, and the thrust-type force-applying member applies a slowly released light force to the twisted tooth, and at the same time plays an auxiliary role in controlling the torsion direction of the twisted tooth.

[0056] At the same time, the middle part of the base of the orthodontic appliance is divided into a left base part and a right base part, and the arch expansion force member is installed between the left base part and the right base part. The arch expansion force member includes a left retaining part, a right retaining part and a spiral force member located between the left retaining part and the right retaining part. The spiral force member is used to apply force to expand the gap between the two retaining parts, thereby transmitting the correction force through the base to the teeth acted by the retaining member, so as to open the mid-palatal suture and widen the maxillary bone, while relieving the problems of crowded teeth and narrow dental arch.

[0057] The orthodontic appliance is a removable orthodontic appliance with an arch expansion force member and a tooth twisting force member. Its force couple is a lightweight force couple, which avoids the risk of root apex absorption and tooth loosening caused by excessive force on the arch wire of a fixed orthodontic appliance. It intervenes in the severe tooth twisting of children in the alternation period of deciduous teeth and provides protection for the normal eruption of permanent teeth in the later period. It is a preventive orthodontic treatment. At the same time, the arch expansion force member is used to open the mid-palatal suture, widen the maxillary bone, relieve tooth crowding, and thus solve the problem of narrow dental arch. Because in the process of opening the mid-palatal suture, the thrust-type force member in the twisting force member adopts a multi-curved spring, the thrust is a light force that is slowly released, and at the same time plays an auxiliary role in controlling the force direction of the twisted tooth, and will not apply excessive correction force to the twisted tooth.

[0058] The following describes in detail the present invention's removable maxillary appliance for the transitional period and its manufacturing method, with reference to the accompanying drawings and specific implementation examples. In the following description, different references to "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0059] Example 1:

[0060] Crowding of the teeth due to twisting of the upper front teeth and narrow dental arch is a common malocclusion in children, especially during the period of tooth replacement. Figures 2A to 2C In the first embodiment shown, the removable appliance includes a retaining member 1, an arch expansion force member 4, and a twisting force member 2 for straightening the twisted anterior teeth, wherein:

[0061] In this embodiment, the retainer 1 includes a base, an occlusal pad, a retaining clasp 16, and a hyperbolic labial arch 15. The base covers the maxillary palate and the palatal side of the dentition. The base is split into a left base portion 11 and a right base portion 12 at the center. The left occlusal pad 13, integrally formed with the left base portion 11, covers the occlusal surface of the left teeth. The right occlusal pad 14, similarly integrally formed with the right base portion 12, covers the occlusal surface of the right teeth (no occlusal pad is provided on the occlusal surface of the anterior teeth). Multiple retaining clasps 16 are provided, each fixed to the base and clamped onto the teeth on both sides. The hyperbolic labial arch 15 is used to wrap around the labial crowns of the anterior teeth, with its curved ends extending through the interdental space and embedded in the left base portion 11 and the right base portion 12, respectively. The retainer 1 provides stable support and retention for the rotational force applied to the twisted tooth 01. Simultaneously, while correcting the twisted tooth 01, the occlusal pad is used to relieve occlusal interference and provide occlusal clearance.

[0062] The retaining clasp 16 is a single-arm clasp and / or an arrow clasp. For the single-arm clasp, one end is buried in the corresponding base, and the other end holds the crown of the adjacent tooth to achieve a retention effect; for the arrow clasp, both ends are buried in the corresponding base, and the side away from the base forms a closed annular structure with the base to be sleeved on the teeth on both sides to achieve a retention effect.

[0063] The torsion force applying member 2 includes a tension type force applying member 21 formed by a bracket 211, a traction hook 212 and an elastic member 213. The bracket 211 includes a base and a bracket wing fixed on the base. The bracket wing is attached with a traction hook for traction. The base is fixed (for example, bonded) to the middle of the crown on the labial side of the torsion tooth 01; the traction hook 212 is arranged on the side opposite to the torsion direction of the torsion tooth 01 (i.e. Figure 2A The hook portion of the traction hook 212 is located on the labial side, and the tail portion of the traction hook 212 is embedded in the base on the side opposite to the torsion direction of the torsion tooth 01 (i.e., in this embodiment, Figure 2A The bracket 211 is connected to the traction hook 212 by an elastic member 213, and the elastic member 213 is respectively hung on the hook of the bracket 211 and the hook of the traction hook 212. The elastic member 213 is stretched and abuts against the labial crown of the twisted tooth 01 (the stretching direction of the elastic member 213 is consistent with the long axis direction of the twisted tooth 01). The tension generated by the elastic member 213 is applied to the twisted tooth 01 through the bracket 212 (see Figure 2B The tension is applied at point D on the labial side of bracket 212. The torque generated by this tension is opposite to the twisting direction of the twisted tooth 01 (elastic member 213 applies a pulling force to the twisted tooth 01, causing it to straighten). Elastic member 213 is preferably a rubber chain. The range of force applied by this rubber chain is determined by the root area and depth of the twisted tooth 01. For example, a physician assesses the root of the twisted tooth 01 by taking dental X-rays. Generally, the larger the root area, the greater the force it can withstand. Typically, the tension applied by elastic member 213 is approximately 50g.

[0064] The torsion force applying member 2 also includes a thrust type force applying member 22, which is located on the palatal side, one end of which is embedded in the base (the right base portion 112 in this embodiment) on the side opposite to the torsion direction of the torsion tooth 01 (i.e., the distal side of the torsion tooth 01), and the other end of which is in contact with the palatal side of the torsion tooth 01 (i.e., Figure 2A The thrust type force applying member 22 applies a light thrust to the twisted tooth 01 (the force application point P of the thrust is located on the palatal side of the twisted tooth 01, and the torque direction of the thrust is opposite to the twisting direction of the twisted tooth 01). The thrust and the pulling force of the elastic member 213 on the twisted tooth 01 form a pair of couples, forming a combined traction force, and at the same time play an auxiliary role in controlling the twisting direction, which helps to gradually correct the twisted tooth 01.

[0065] Preferably, the thrust-type force applying member 22 is a multi-curved spring 3, see Figure 3 The multi-bend spring 3 is a multi-bend structure of a sine or cosine shape made by bending a stainless steel round wire (for example, a stainless steel round wire with a diameter of 0.40 mm). One end of the multi-bend spring 3 is buried in the base of the distal side of the torsion tooth 01 as a fixed end 31, and the other end is a free end 33 for abutting against the mesial side of the torsion tooth 01 so as to apply a thrust to the torsion tooth 01 in the opposite direction of the torsion direction; there are multiple parabolic curves 32 connected in sequence between the fixed end 31 and the free end 33 of the multi-bend spring 3, and the effective The number of parabolic curves 32 (the parabolic curve embedded in the base is not a valid parabolic curve) and the curvature value of the parabolic curve 32 (that is, the inverse of the radius of the top arc or bottom arc of the parabolic curve 31) are determined according to the position between the torsion tooth 01 and the base and the magnitude of the force required to correct the torsion tooth 01. Once the valid number of parabolic curves 32 is determined, the force of the multi-curved spring 3 for displacement can be adjusted by adjusting the curvature value of the parabolic curve 32. Generally, the larger the curvature value, the smaller the force.

[0066] During installation, the free end 33 of the multi-curve spring 3 is placed in close contact with the side of the palatal surface of the twisted tooth 01 that has the same twisting direction (the free end 33 is bent according to the shape of this surface), so that the height of the force application point of the multi-curve spring 3 is 1 / 2 of the crown height of the twisted tooth 01, to ensure that the twisted tooth 01 is horizontally straightened as a whole. Preferably, the force applied by the multi-curve spring 3 is adjusted to about 50g by adjusting the curvature value of the parabolic curve 32 (the specific value of the force is adjusted according to the situation of the twisted tooth 01. Generally, the greater the degree of tooth twisting, the smaller the force applied by the multi-curve spring 3, to prevent damage to the periodontium of the twisted tooth 01). The multi-curve spring 3 cooperates with the tension applied by the elastic member 213 to form a lightweight force couple, which is suitable for orthodontic correction of individual anterior tooth twisting that occurs after the eruption of anterior teeth during the dentition replacement period.

[0067] The thrust application point P of the multi-curved spring 3 located on the palate side and the tension application point D of the elastic member 213 located on the lip side (see Figure 2B ) are at the same height in the middle of the torsion tooth 01. When the multi-curved spring 3 pushes on the torsion tooth 01 and the elastic member 213 pulls on the torsion tooth 01, forming a force couple, the correction force is directed through the tooth's center of resistance, preventing damage to the tooth from being depressed or stretched. This force couple effectively returns the torsion tooth to its original position, relieving occlusal interference between the upper and lower anterior teeth, restoring the patient's dental and maxillofacial aesthetics, and facilitating the normal eruption of adjacent teeth or secondary correction (for example, maintaining sufficient clearance for adjacent teeth to erupt).

[0068] As the twisted tooth 01 is gradually corrected by the force couple generated by the twisting force member 2, excessive force may cause the twisted tooth 01 to tilt toward the labial side. The hyperbolic labial arch 15, positioned over the anterior teeth, not only provides retention but also limits the position of the twisted tooth 01, preventing it from tilting excessively toward the labial side during the correction process.

[0069] The arch expansion force member 4 is used to open the palatal suture while twisting the tooth 01 to straighten it, so as to widen the maxillary bone, relieve the crowding of the teeth, and thus solve the problem of narrow dental arch. Figure 2A and Figure 5 The expansion force member 4 includes a left retaining portion 41, a right retaining portion 42 and a spiral force applying portion 43. The left retaining portion 41 and the right retaining portion 42 are respectively buried in the disconnected left base portion 11 and the right base portion 12. The spiral force applying portion 43 is located between the left retaining portion 41 and the right retaining portion 42 to connect the left retaining portion 41 and the right retaining portion 42.

[0070] In one embodiment, the spiral force-applying portion 43 is welded to the left retaining portion 41 and the right retaining portion 42, respectively. The spiral force-applying portion 43 is provided with a spiral hole 44 and a force-applying key 46. A preset force-applying direction mark (such as an arrow indicating the direction) is provided on the left retaining portion 41 or the right retaining portion 42. After the force-applying key 46 is inserted into the spiral hole 44 and rotated in the predetermined force-applying direction, the gap between the two retaining portions can be expanded, so that the spiral force-applying portion 43 transmits the correction force to the teeth acted on by the retaining component 1 through the base, opens the mid-palatal suture, widens the maxillary bone, thereby relieving dental crowding and solving the problem of narrow dental arch.

[0071] Obviously, the expansion force applying member may also adopt a traditional expansion screw, and its specific structure will not be described in detail.

[0072] Example 2:

[0073] In the second embodiment, in the case where the adjacent teeth of the twisted tooth 01 have not erupted, the adjacent position of the twisted tooth 01 (i.e., the gap between the unerupted teeth) is defined as the missing tooth gap 02. In particular, when the twisted tooth 01 is twisted relatively greatly, a longer time of correction is required. In the process of applying the correction force, the twisted tooth 01 is easily tilted toward the missing tooth gap 02 due to improper force application.

[0074] See also Figure 4A and Figure 4B In order to avoid this phenomenon, a limiting clasp 23 is installed at the tooth gap 02. The limiting clasp 23 is a single-arm clasp made by bending an arch wire (for example, a 0.70 mm stainless steel wire), including an arm end and a bent end. The arm end of the limiting clasp 23 is buried in the base (in this embodiment). Figure 4A In the figure, the arm end of the limiting clamp 23 is buried in the right base portion 12), and the curved end extends from the tooth gap 02 to the labial side and embraces the labial crown of the twisted tooth 01, limiting the twisted tooth 01 and preventing the twisted tooth 01 from tilting toward the side of the tooth gap.

[0075] method

[0076] The above-mentioned removable appliance is made on a maxillary plaster model. The manufacturing process of the removable appliance is described using Example 1 as an example. The manufacturing method includes the following steps:

[0077] Step 1: Prepare a maxillary plaster model based on the patient's maxillary condition;

[0078] Step 2: Apply a layer of separating agent on the dried maxillary plaster model, and place the bent double-curved labial bow 15, the retaining clasp 16, and the traction hook 212 in the predetermined position (see Figure 2A The parabolic curve 32 of the bent multi-curve spring 3 near the free end is squeezed according to the predetermined thrust and sealed with a wax drop, and then the multi-curve spring 3 is raised with a wax seat to be placed in the predetermined position (see Figure 2A The spiral hole 44 of the expansion force member 4 is sealed, and the bottom of the expansion force member 4 is fixed to the middle of the maxilla with wax. A spacer (e.g., a plastic sheet) of a certain thickness is vertically arranged in the base area of ​​the maxilla to form a central disconnection seam between the left base portion 11 and the right base portion 12. Finally, the prepared self-curving material is filled in the base area (i.e., the preset base coverage area) and the occlusal pad area (i.e., the preset occlusal pad coverage area) of the maxillary plaster model. After the self-curving material solidifies, a one-piece base and occlusal pad with a middle disconnection are formed. At the same time, the base fixes the hyperbolic labial arch 15, the retaining clasp 16, the traction hook 212, the multi-curved spring 3, and the expansion force member 4.

[0079] Step three, remove the spacer in the above model and demold it (i.e. remove the orthodontic appliance from the maxillary plaster model, remove the wax, trim, grind and polish it, and open the spiral hole 44), and fix the bracket 211 to the predetermined position of the patient's twisted tooth 01. According to the positional relationship between the traction hook 212 and the bracket 211, select a suitable elastic member 213 so that the twisting force meets the predetermined requirements.

[0080] The process of wearing the removable appliance is as follows:

[0081] The bracket 211 is fixed (for example, bonded) to the middle of the crown on the labial side of the twisted tooth 01, and the orthodontic appliance is installed in place so that the free end of the multi-curved spring 3 is in contact with the mesial side of the torsion direction of the palatal side of the twisted tooth 01, and the elastic member 213 is used to connect the distal wing of the bracket 211 with the hook portion of the traction hook 212, so that the thrust application point of the multi-curved spring 3 on the palatal side and the tension application point of the elastic member 213 on the labial side are at the same height in the middle of the twisted tooth 01, and the thrust of the multi-curved spring 3 on the twisted tooth 01 and the tension of the elastic member 213 on the twisted tooth 01 form a pair of force couples, and the force application direction of the force couple is opposite to the torsion direction of the twisted tooth 01.

[0082] The manufacturing process and wearing process of the removable orthodontic appliance in Example 2 are basically the same as those in Example 1 and will not be described again here.

[0083] The above-mentioned removable orthodontic appliance is made on the maxillary model. The base and the occlusal pad are both made of self-curing plastic solidified in one piece. The base covers the maxillary palate and the palatal side of the dentition, and the occlusal pad covers the occlusal surfaces of the teeth on both sides (the occlusal surface of the front teeth is not covered by the occlusal pad). After the patient wears it, the base and the occlusal pad are not visible when speaking normally or opening the mouth, and do not affect the beauty of the teeth; the retaining part 1 (that is, the base, the hyperbolic labial bow 15 and the retaining clasp 16) uses the teeth other than the twisted tooth 01 as a whole as support, which can achieve good retention and make the orthodontic appliance balanced and stable in the oral cavity.

[0084] The movable orthodontic appliance of the present invention only has the bracket 211 bonded on the twisted tooth 01, and the other structures are embedded in the base, which is convenient for removal and beneficial to the maintenance of oral hygiene; the correction force of the twisting force-applying member 2 only acts on the twisted tooth 01, and has basically no effect or damage on other teeth, reducing the incidence of ulcers in patients, and is suitable for orthodontic occasions for children who have just had their teeth replaced.

[0085] Generally, the force applied by the torsion force member 2 of the orthodontic appliance needs to be adjusted every month or so. The orthodontic appliance can adjust the force applied to the torsion tooth 01 by replacing the elastic member 213 and adjusting the curvature value of the parabolic curve 32 of the multi-curve spring 3 to better exert the correction effect.

[0086] In order to address the situation of crowded teeth and narrow dental arches, an arch expansion force member 4 is set in the middle of the maxilla, and the correction force is transmitted to the teeth acted upon by the retaining member 1 through the base, so as to open the mid-palatal suture and widen the maxilla, while at the same time solving the problems of crowded teeth and narrow dental arches.

[0087] Those skilled in the art should understand that these embodiments are only used to illustrate the present invention and do not limit the scope of the present invention. Various equivalent variations and modifications made to the present invention belong to the disclosure of the present invention.

Claims

1. A maxillary removable appliance for the period of tooth replacement, characterized in that: It includes a retaining member, a torsion force member and an expansion force member, wherein: The retaining member is used to connect the teeth on both sides together to form a tooth anchorage, including a base covering the upper jaw and the palatal side of the dentition, an occlusal pad covering the occlusal surface of the dentition on both sides, a hyperbolic lip bow (15) wrapping the labial crown of the front teeth, and a plurality of retaining clasps (16) clamped on the teeth on both sides, the base including a left base part and a right base part, the occlusal pad including a left occlusal pad and a right occlusal pad, the left occlusal pad and the left base part are integrally formed, and the right occlusal pad and the right base part are integrally formed, the two curved ends of the hyperbolic lip bow (15) are respectively fixedly embedded in the left base part and the right base part, and each retaining clasp (16) is respectively fixed on the base; The torsion force applying member comprises a tension-type force applying member (21) and a thrust-type force applying member (22) respectively connected to the base, the tension-type force applying member (21) is arranged on the labial side of the torsion tooth, and the thrust-type force applying member (22) is arranged on the palatal side of the torsion tooth. The tension-type force applying member and the thrust-type force applying member simultaneously apply torque in the same direction to the torsion tooth to make the torsion tooth turn straight, and the force application points of the two are arranged at the same height in the middle of the torsion tooth to form a pair of force couples; The expansion force applying member (4) is arranged between the left base portion and the right base portion and connects the left base portion and the right base portion, and is used to apply an outward thrust to the base portions on both sides; The tension-type force applying member (21) comprises: A bracket (211) is used for fixing to the middle part of the crown on the labial side of the twisted tooth; A traction hook (212) is provided at the tooth gap on the side opposite to the torsion direction of the torsion tooth, the hook portion of the traction hook is located on the lip side, and the tail portion is embedded in the base; and An elastic member (213) has one end connected to the draw hook of the bracket (211) and the other end connected to the hook portion of the traction hook, and the stretching direction of the elastic member is consistent with the long axis direction of the torsion tooth; The thrust-type force applying member (22) is a multi-curved spring, which is arranged on the palatal side of the twisting tooth, with one end embedded in the base and the other end abutting against the palatal side of the twisting tooth, and is used to apply a thrust to the twisting tooth in the opposite direction of its twisting direction.

2. The maxillary removable appliance for the period of tooth replacement according to claim 1, characterized in that: The elastic member (213) is a rubber chain.

3. The maxillary removable appliance for the period of transitional dentition according to claim 1, characterized in that: The multi-bend spring is a sine or cosine multi-bend structure made of stainless steel round wire. One end is buried in the base as a fixed end, and the other end is a free end used to abut on the torsion tooth. There are multiple parabolic bends connected in sequence between the two ends.

4. The maxillary removable appliance for the transitional period according to claim 3, characterized in that: The force application direction of the multi-curved spring is opposite to the torsion direction of the torsion tooth, and the height of the force application point is 1 / 2 of the crown height of the torsion tooth.

5. The maxillary removable appliance for the period of transitional dentition according to claim 1, characterized in that: The retaining clamp (16) is an arrow clamp and / or a single-arm clamp.

6. The maxillary removable appliance for the transitional period according to claim 1, characterized in that: The expansion force member (4) comprises a left retaining portion, a right retaining portion and a spiral force applying portion, wherein the spiral force applying portion is located between the left retaining portion and the right retaining portion and connects the left retaining portion and the right retaining portion; the left retaining portion and the right retaining portion are respectively embedded in the left base supporting portion and the right base supporting portion.

7. The maxillary removable appliance for the transitional period according to claim 6, characterized in that: The spiral force-applying part is welded to the left fixing part and the right fixing part respectively. The spiral force-applying part is provided with a spiral hole and a force-applying key. A preset force-applying direction mark is provided on the left fixing part or the right fixing part. The force-applying key is used to insert the spiral hole and rotate the force in the predetermined force direction.

8. The maxillary removable appliance for the period of transitional dentition according to any one of claims 1 to 7, characterized in that: In response to the situation where the adjacent teeth of the twisted tooth have not erupted and a gap (02) between the adjacent teeth of the twisted tooth appears, the twist force applying member also includes a limiting clasp (23). The limiting clasp (23) is a single-arm clasp made by bending the arch wire and is arranged at the missing tooth gap (02) of the twisted tooth. The arm end of the limiting clasp is buried in the base, and the curved end extends from the missing tooth gap to the labial side and surrounds the labial crown of the twisted tooth.

9. A method for manufacturing the maxillary removable appliance for the transitional period according to any one of claims 1 to 8, comprising the following steps: 1) Prepare a maxillary plaster model based on the patient's oral and maxillary condition; 2) Apply a layer of separating agent on the dried maxillary plaster model, place the bent hyperbolic labial bow, retention clasp and traction hook in the predetermined position in sequence, and temporarily fix them with wax drops; squeeze the parabolic curve of the bent multi-curved spring close to the free end according to the predetermined thrust and seal it with wax drops, then use a wax seat to raise the multi-curved spring to place it in the predetermined position; fill the spiral hole of the expansion force member, and fix the bottom of the expansion force member to the middle of the maxilla with wax, and vertically set a spacer of a certain thickness in the base area of ​​the middle of the maxilla to form a middle disconnection seam between the left base part and the right base part; finally, fill the base area and occlusal pad area of ​​the maxillary plaster model with the prepared self-setting material, and after the self-setting material solidifies, form an integrated base and occlusal pad with a middle disconnection, and at the same time, the base fixes the hyperbolic labial bow, retention clasp, traction hook, multi-curved spring and expansion force member; 3) Remove the spacer from the above model and demould it, and fix the bracket on the predetermined position of the patient's twisted tooth. According to the positional relationship between the traction hook and the bracket, select a suitable elastic member so that the twisting force meets the predetermined requirements.

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