A nickel-titanium alloy tooth correction wire and preparation method thereof

Abstract

The present invention belongs to the technical field of dental orthodontic wires and relates to a nickel-titanium alloy dental orthodontic wire and a method for preparing the same. The present invention provides a nickel-titanium alloy dental orthodontic wire, comprising a deformed tooth correction segment and a normal tooth segment; the deformed tooth correction segment of the nickel-titanium alloy dental orthodontic wire has a higher martensitic deformation stress platform value than the normal tooth segment. The nickel-titanium alloy dental orthodontic wire provided by the present invention has different martensitic deformation stress platform values ​​at different locations, and nickel-titanium alloy dental orthodontic wire segments with high martensitic deformation stress platform values ​​are specifically designed for deformed tooth locations, thereby improving the comfort of wearing the wire.

Description

Technical Field

[0001] The invention belongs to the technical field of dental orthodontic wires and relates to a nickel-titanium alloy dental orthodontic wire and a preparation method thereof. Background Art

[0002] When the temperature is greater than the termination temperature (Af) of the reverse martensitic transformation of nickel-titanium shape memory alloy, nickel-titanium shape memory alloy will not produce plastic yield immediately after the stress / strain linear elastic stage ends. Instead, due to the martensitic phase transformation, it continues to deform for a period of time with stable stress, thus having a higher elongation (8%). This property is called superelasticity. Dental correction wires made of superelastic nickel-titanium alloy wire will not quickly lose tension due to the recovery of deformed teeth. Therefore, compared with dental correction wires made of traditional iron wires, superelastic nickel-titanium correction wires can greatly reduce the number of times the dental correction wires are tightened, thereby reducing the orthodontic treatment time for doctors and patients. However, the overall composition and tensile properties of nickel-titanium alloy correction wires manufactured by traditional processes are consistent. During the correction of deformed teeth, the tension generated by tightening the correction wire acts on the tooth as a whole. The tension generated by the correction wire at the deformed teeth is similar to that at the normal teeth, and it is impossible to generate a specific tension on the deformed teeth that is higher than that of normal teeth. Summary of the Invention

[0003] In view of this, the present invention provides a nickel-titanium alloy dental correction wire and a preparation method thereof. The nickel-titanium alloy dental correction wire provided by the present invention has different martensitic deformation stress platform values ​​at different parts, and can generate targeted tension on deformed teeth and normal teeth respectively.

[0004] In order to achieve the above objectives, the present invention provides the following technical solutions:

[0005] The present invention provides a nickel-titanium alloy dental correction wire, which comprises a deformed tooth correction section and a normal tooth section; in the nickel-titanium alloy dental correction wire, the martensitic deformation stress platform value of the deformed tooth correction section is higher than that of the normal tooth section.

[0006] Preferably, the diameter of the nickel-titanium alloy dental correction wire is 0.1 to 1.2 mm.

[0007] Preferably, the deformed tooth correction section includes a small degree tooth deviation correction section and / or a large degree tooth deviation correction section; the offset of the small degree tooth deviation is 1 to 2.5 mm from the normal teeth; the offset of the large degree tooth deviation is 2.6 to 5 mm from the normal teeth.

[0008] Preferably, the martensitic deformation stress platform value of the nickel-titanium alloy dental correction wire in the small degree tooth deviation correction section is 140-200 MPa; the martensitic deformation stress platform value of the nickel-titanium alloy dental correction wire in the high degree tooth deviation correction section is 201-300 MPa.

[0009] Preferably, the martensitic deformation stress platform value of the normal tooth segment in the nickel-titanium alloy dental correction wire is 70 to 139 MPa.

[0010] Preferably, the atomic percentage content of nickel in the nickel-titanium alloy dental correction wire is 50-52%.

[0011] The present invention also provides a method for preparing the nickel-titanium alloy dental correction wire described above, comprising the following steps:

[0012] According to normal teeth and deformed teeth, the lengths of the deformed tooth correction segment and the normal tooth segment in the nickel-titanium alloy dental correction wire and the martensitic deformation stress platform values ​​of the nickel-titanium alloy dental correction wire required for different correction segments are determined;

[0013] Using a selective laser melting method, nickel-titanium alloy powder is segmented and printed according to the martensitic deformation stress platform value and length required for normal teeth and deformed teeth to obtain the nickel-titanium alloy dental correction wire;

[0014] The length of the correction wire required for normal teeth is the outer contour value of the normal teeth; the length of the correction wire required for deformed teeth is the sum of the outer contour width of the deformed teeth and 2 times the deviation.

[0015] Preferably, the particle size of the nickel-titanium alloy powder is 15 to 53 μm.

[0016] Preferably, the conditions of the selective laser melting method include laser power: 50-250 W; scanning rate: 80-1500 mm / s; scanning spacing: 40-180 μm; layer thickness: 30-50 μm; and rotation angle: 45-90°.

[0017] The present invention provides a nickel-titanium alloy dental brace wire comprising a deformed tooth correction section and a normal tooth section. The deformed tooth correction section of the nickel-titanium alloy dental brace wire has a higher martensitic deformation stress plateau value than the normal tooth section. The nickel-titanium alloy dental brace wire provided by the present invention has different martensitic deformation stress plateau values ​​at different locations. Nickel-titanium alloy brace wire sections with high martensitic deformation stress plateau values ​​are specifically designed for deformed tooth locations, thereby improving wearer comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the nickel-titanium alloy dental correction wire in Example 1 acting on teeth. DETAILED DESCRIPTION

[0019] The present invention provides a nickel-titanium alloy dental correction wire, which comprises a deformed tooth correction section and a normal tooth section; in the nickel-titanium alloy dental correction wire, the martensitic deformation stress platform value of the deformed tooth correction section is higher than that of the normal tooth section.

[0020] In the present invention, unless otherwise specified, the reagents used are commercially available products well known to those skilled in the art.

[0021] In the present invention, the martensite deformation stress plateau value belongs to a section in the tensile curve, which is defined in English as stress plateau due to the martensite transformation.

[0022] In the present invention, the diameter of the nickel-titanium alloy dental correction wire is preferably 0.1-1.2 mm, more preferably 0.15-1 mm, and most preferably 0.4-0.8 mm. In the present invention, the martensitic deformation stress platform value of the deformed tooth correction segment of the nickel-titanium alloy dental correction wire is higher than that of the normal tooth segment.

[0023] In the present invention, the deformity correction segment includes a minor tooth misalignment correction segment and / or a major tooth misalignment correction segment. The minor tooth misalignment preferably has an offset of 1 to 2.5 mm, more preferably 1.5 to 2.0 mm, relative to normal teeth. The major tooth misalignment preferably has an offset of 2.6 to 5 mm, more preferably 3.0 to 4.5 mm, relative to normal teeth. In the present invention, the atomic percentage of nickel in the nickel-titanium alloy dental wire is preferably 50 to 52%, more preferably 50.3 to 51.4%.

[0024] In the present invention, the martensitic deformation stress plateau value of the nickel-titanium alloy dental braces wire for correcting minor tooth misalignment is preferably 140-200 MPa, more preferably 150-195 MPa; the martensitic deformation stress plateau value of the nickel-titanium alloy dental braces wire for correcting major tooth misalignment is preferably 201-300 MPa, more preferably 210-295 MPa. In the present invention, the martensitic deformation stress plateau value of the nickel-titanium alloy dental braces wire for correcting normal tooth segments is preferably 70-139 MPa, more preferably 75-135 MPa.

[0025] The present invention also provides a method for preparing the nickel-titanium alloy dental correction wire described above, comprising the following steps:

[0026] According to normal teeth and deformed teeth, the lengths of the deformed tooth correction segment and the normal tooth segment in the nickel-titanium alloy dental correction wire and the martensitic deformation stress platform values ​​of the nickel-titanium alloy dental correction wire required for different correction segments are determined;

[0027] Using a selective laser melting method, nickel-titanium alloy powder is segmented and printed according to the martensitic deformation stress platform value and length required for normal teeth and deformed teeth to obtain the nickel-titanium alloy dental correction wire;

[0028] The length of the correction wire required for normal teeth is the outer contour value of the normal teeth; the length of the correction wire required for deformed teeth is the sum of the outer contour width of the deformed teeth and 2 times the deviation.

[0029] The present invention determines the lengths of the deformed tooth correction section and the normal tooth section in the nickel-titanium alloy dental correction wire and the martensitic deformation stress platform values ​​of the nickel-titanium alloy dental correction wire required for different correction sections based on normal teeth and deformed teeth.

[0030] In the present invention, the length of the correction wire required for normal teeth is preferably the outer contour value of normal teeth. In the present invention, the length of the correction wire required for deformed teeth is preferably the sum of the outer contour width of the deformed teeth and twice the deviation.

[0031] The present invention utilizes a selective laser melting method to print nickel-titanium alloy powder in sections according to the martensitic deformation stress platform value and length required for normal teeth and deformed teeth, thereby obtaining the nickel-titanium alloy tooth correction wire.

[0032] In the present invention, the particle size of the nickel-titanium alloy powder is preferably 13 to 53 μm, more preferably 15 to 50 μm.

[0033] In the present invention, the conditions of the selective laser melting method preferably include: the laser power is preferably 50 to 250 W, more preferably 60 to 220 W; the scanning rate is preferably 80 to 1500 mm / s, more preferably 200 to 1350 mm / s; the scanning spacing is preferably 40 to 180 μm, more preferably 80 to 120 μm; the layer thickness is preferably 30 to 50 μm, more preferably 30 to 45 μm; the rotation angle is preferably 45 to 90°, more preferably 67° to 90°.

[0034] In the present invention, the printing conditions of the nickel-titanium alloy dental correction wire of the normal tooth segment preferably include: the laser power is preferably 120W, the scanning speed is preferably 800mm / s, the printing layer thickness is preferably 30μm, and the scanning interval is 60μm.

[0035] In the present invention, the printing conditions of the nickel-titanium alloy dental correction wire of the deformed dental correction segment preferably include: the laser power is preferably 120W, the scanning speed is preferably 800mm / s, the printing layer thickness is preferably 30μm, and the scanning spacing is 80-100μm.

[0036] In the present invention, after the segmented printing, it is preferred that the segmented printed nickel-titanium alloy correction wire is cut, formed, polished and cleaned in sequence.

[0037] In the present invention, the cutting molding is preferably wire cutting molding. In the present invention, the grinding and polishing is preferably performed by sequentially using 400 mesh and 800 mesh sandpapers.

[0038] In the present invention, the cleaning is preferably ultrasonic cleaning. The present invention does not specifically limit ultrasonic cleaning, and ultrasonic cleaning can be used to remove residues on the surface of the nickel-titanium alloy correction wire using operations well known to those skilled in the art.

[0039] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0040] Example 1

[0041] like Figure 1 As shown, first, the total length of the outer contour of the teeth of the patient with tooth deformity is measured to be 143.5 mm, the width of the deformed tooth 7 on the left side is measured to be 7.5 mm and the offset distance is 3.8 mm, and the width of the deformed tooth 8 on the right side is measured to be 8.4 mm and the offset distance is 2.8 mm.

[0042] According to the length of the deformed tooth No. 7, the deformed tooth No. 8 and the normal tooth segment and the required martensite deformation stress platform value, Ni with a particle size of 15 to 53 μm was added. 50.6 Ti 49.4 (at %) alloy powder is printed in sections to obtain the nickel-titanium alloy dental correction wire.

[0043] The nickel-titanium alloy orthodontic wire is divided into five sections. The first section is 42.5 mm long, with a scanning pitch of 60 μm, a fixed laser power of 120 W, a scanning speed of 800 mm / s, and a printing layer thickness of 30 μm. The corresponding martensitic stress plateau value for the first section is 130 MPa.

[0044] The length of the second section is 16 mm, the scanning pitch is 100 μm, the fixed laser power is 120 W, the scanning speed is 800 mm / s, and the printing layer thickness is 30 μm; the martensitic stress platform value corresponding to the second section is 230 MPa.

[0045] The length of the third section is 32 mm, the scanning pitch is 60 μm, the fixed laser power is 120 W, the scanning speed is 800 mm / s, and the printing layer thickness is 30 μm; the martensitic stress platform value corresponding to the third section is 130 MPa.

[0046] The length of the fourth section is 16 mm, the scanning pitch is 80 μm, the fixed laser power is 120 W, the scanning speed is 800 mm / s, and the printing layer thickness is 30 μm; the martensitic stress platform value corresponding to the fourth section is 190 MPa.

[0047] The length of the fifth section is 37 mm, the scanning pitch is 60 μm, the fixed laser power is 120 W, the scanning speed is 800 mm / s, and the printing layer thickness is 30 μm; the martensitic stress platform value corresponding to the fourth section is 130 MPa.

[0048] The 3D-printed SLM nickel-titanium alloy orthodontic wire was cut from the substrate using wire cutting, and then the segmented strength SLM nickel-titanium alloy wire was polished using 400-mesh and 800-mesh sandpapers in sequence. Finally, the polished nickel-titanium alloy wire was cleaned using an ultrasonic cleaner to remove surface residues, and anhydrous ethanol was used as the cleaning liquid to obtain the nickel-titanium alloy dental correction wire.

[0049] Figure 1 This is a schematic diagram of the nickel-titanium alloy dental braces wire in Example 1 acting on teeth. Reference numeral 1 represents the first segment of the nickel-titanium alloy dental braces wire, reference numeral 2 represents the second segment of the nickel-titanium alloy dental braces wire, reference numeral 3 represents the third segment of the nickel-titanium alloy dental braces wire, reference numeral 4 represents the fourth segment of the nickel-titanium alloy dental braces wire, and reference numeral 5 represents the fifth segment of the nickel-titanium alloy dental braces wire. Reference numeral 6 represents a normal tooth, reference numeral 7 represents a deformed tooth on the left side, and reference numeral 8 represents a deformed tooth on the right side.

[0050] Testing revealed that when a 5% tension deformation was applied, the stresses on the wires at deformed teeth 7 and 8 were 230 MPa and 190 MPa, respectively, while the stress on the wires at normal teeth was 130 MPa. The diameter of the segmented-strength nickel-titanium alloy wires is 0.16 mm. Therefore, the tensions on the wires at deformed teeth 3 and 4 were 4.6 N and 3.8 N, respectively, while the tension on the wires at normal teeth was 2.6 N. This allows for targeted treatment of deformed teeth from the source.

[0051] In the present invention, the calculation method of the tension of the correction wire is: tension = cross-sectional area × stress.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A nickel-titanium alloy dental correction wire, characterized in that: The nickel-titanium alloy dental correction wire comprises a deformed tooth correction section and a normal tooth section; the martensite deformation stress platform value of the deformed tooth correction section in the nickel-titanium alloy dental correction wire is higher than that of the normal tooth section; the atomic percentage content of nickel in the nickel-titanium alloy dental correction wire is 50-52%; The martensitic deformation stress platform value of the nickel-titanium alloy dental correction wire in the small degree tooth deviation correction section is 140-200 MPa; the martensitic deformation stress platform value of the nickel-titanium alloy dental correction wire in the high degree tooth deviation correction section is 201-300 MPa; The martensitic deformation stress platform value of the normal tooth segment in the nickel-titanium alloy dental correction wire is 70 to 139 MPa; The deformed tooth correction section includes a minor tooth deviation correction section and / or a major tooth deviation correction section; the minor tooth deviation has an offset of 1 to 2.5 mm relative to normal teeth; the major tooth deviation has an offset of 2.6 to 5 mm relative to normal teeth; The method for preparing the nickel-titanium alloy dental correction wire comprises the following steps: According to normal teeth and deformed teeth, the lengths of the deformed tooth correction segment and the normal tooth segment in the nickel-titanium alloy dental correction wire and the martensitic deformation stress platform values ​​of the nickel-titanium alloy dental correction wire required for different correction segments are determined; Using a selective laser melting method, nickel-titanium alloy powder is segmented and printed according to the martensitic deformation stress platform value and length required for normal teeth and deformed teeth to obtain the nickel-titanium alloy dental correction wire; The length of the correction wire required for normal teeth is the outer contour value of the normal teeth; the length of the correction wire required for deformed teeth is the sum of the outer contour width of the deformed teeth and 2 times the offset; The conditions of the selective laser melting method include laser power: 50-250W; scanning rate: 80-1500mm / s; scanning spacing: 40-180μm; layer thickness: 30-50μm; rotation angle: 45-90°.

2. The nickel-titanium alloy dental correction wire according to claim 1, characterized in that: The diameter of the nickel-titanium alloy dental correction wire is 0.1 to 1.2 mm.

3. The method for preparing the nickel-titanium alloy orthodontic wire according to any one of claims 1 to 2, characterized in that: The following steps are involved: According to normal teeth and deformed teeth, the lengths of the deformed tooth correction segment and the normal tooth segment in the nickel-titanium alloy dental correction wire and the martensitic deformation stress platform values ​​of the nickel-titanium alloy dental correction wire required for different correction segments are determined; Using a selective laser melting method, nickel-titanium alloy powder is segmented and printed according to the martensitic deformation stress platform value and length required for normal teeth and deformed teeth to obtain the nickel-titanium alloy dental correction wire; The length of the correction wire required for normal teeth is the outer contour value of the normal teeth; the length of the correction wire required for deformed teeth is the sum of the outer contour width of the deformed teeth and 2 times the deviation; The conditions of the selective laser melting method include laser power: 50-250W; scanning rate: 80-1500mm / s; scanning spacing: 40-180μm; layer thickness: 30-50μm; rotation angle: 45-90°.

4. The preparation method according to claim 3, characterized in that The particle size of the nickel-titanium alloy powder is 15 to 53 μm.

Images