KR102399423B1 - Manufacturering of orthodontic mini screw and method of surface treatment - Google Patents

Abstract

The present invention relates to an orthodontic mini screw and a manufacturing method thereof. More specifically, the orthodontic mini screw comprises: a head part; and a body integrally formed with the head part and including a threaded part and a screw thread protruding from a surface of the threaded part. Also, surfaces of the head part and body are coated with a plurality of protruding titanium dioxide nanotube layers and a calcium phosphate layer formed on the titanium dioxide nanotube layers, wherein the calcium phosphate layer is filled with strontium ranelate. The orthodontic mini screw as described above maximizes bioactivity with the bone by forming flutes to increase a specific surface area while reducing a length of the body and widening a diameter thereof, and prevents initial shaking and frequent loosening of the screw. The orthodontic mini screws are surface-treated with a low-temperature calcification circulation treatment technique after anodization so as to form a dense and durable calcium phosphate layer. Also, the orthodontic mini screws are filled with strontium ranelate, which inhibits bone resorption and promotes bone production, thereby preventing activities of osteoclasts which become more active when the mini screw made of titanium are implanted in human bones. Furthermore, the orthodontic mini screws show an effect of dramatically improving a success rate of orthodontic procedures by promoting bioactivity between titanium implants and bones.

Description

Manufacture of orthodontic mini screw and method for surface treatment thereof

The present invention relates to an orthodontic miniscrew and a method for manufacturing the same, and more particularly, to form a dense calcium phosphate layer on apatite by anodizing and then surface treatment using a calcification cycle treatment technique, and to inhibit and promote bone resorption. It was loaded with working strontium ranelate. When a titanium miniscrew is placed in the palate, it is stabilized. At the beginning, the damaged bone around the implantation area is absorbed by osteoclasts, and then osteoblasts generate new bone and the miniscrew is stabilized. Even if it is loose and light load, it can be shaken and fall off. During the shaking process, the surrounding bones and tissues are damaged, so the above process is repeated, and the orthodontic treatment is delayed due to the mini screw falling off. In addition, if the screw part is long, side effects such as penetrating the tooth root or fracture may occur. The present invention greatly reduces the length of the threaded portion and forms a flute in order to suppress the drop-off due to the initial shaking after the implantation of the miniscrew and to suppress the problem of the absorption of the root due to penetration, thereby increasing the mechanical holding force, and also nanotubes. It is a method that dramatically improves the success rate of orthodontic treatment by forming a bone structure and loading it with bioactive substances or drugs to induce early adhesion to the bone, and obtain mechanical and chemical retention by bone union obtained from the flute site. It relates to an orthodontic mini-sk and a method for manufacturing the same.

Orthodontic mini screw refers to a set screw that obtains strong orthodontic power by placing it in the root, gum, palate, etc. during the orthodontic process. Orthodontic miniscrews were introduced to obtain essential fixation power in the course of orthodontic treatment, but the areas where miniscrews are mainly used are limited in that they cannot be deeply implanted due to the anatomical characteristics of the alveolar bone including the root and periodontal ligament. There are restrictions on the length. In addition, when the cortical bone of the consumer (patient) was thin, it was frequently pulled out due to wobbling during orthodontic treatment.

The most frequently used miniscrews in the clinical field are implanted with a thread length of 6 mm or more. However, since there is no adhesion with the bone, it causes pain around the implantation site, or in the case of the maxillary molars, it penetrates the maxillary sinus located above the root of the tooth. Severe inflammation progressed at the site, resulting in weakening of the bone around the implantation site.

Accordingly, various research and development were conducted to reduce patient discomfort, obtain stable fixation, and reduce the frequency of drop-off and fracture. In order to increase the holding force, the diameter of the screw part increased, and the formation of a flute to increase the surface area of the screw part was reviewed. Recently, as a method of inducing bone union by bioactive surface treatment or treating with a bisphosphonate drug to decrease the function of osteoclasts to suppress bone resorption at the initial stage of implantation, thereby increasing the retention force at the initial stage of implantation, the length of the existing thread has been reduced. Studies to reduce the size of 6 mm or more to the level of 3 mm have been continuously conducted.

As is well known, orthodontic miniscrews have the advantages of being cheaper than dental prosthetics and restoration implants and have the advantage of immediate loading due to a simple procedure. The failure rate of more than % occurred, most of which was due to the failure of securing the initial fixation force. In addition, most of the types of failure to secure the fixation power of the miniscrew occur within 1 to 2 months after the procedure. This is because orthodontic miniscrews are used for alveolar and palatine bones, which have relatively thin bones, unlike general dental implants. Accordingly, in consideration of the weak use environment, osteoclasts contributing to the initial bone resorption in the process of stabilizing the screw after implantation of the miniscrew together with methods for improving the shape of the orthodontic miniscrew, appropriate length and thickness, and inducing early bone union It has reached the research stage that inhibiting bone resorption around the implantation site is effective in improving retention by reducing the function of the implant.

On the other hand, when damage occurs in the bones that make up the skeleton during human life, the osteoclasts that naturally absorb and remove the damaged bones and osteoblasts that create new bones balance and maintain the skeleton. However, as they age, their balance is disturbed, which may lead to weakened bones or osteoporosis. As everyone admits, titanium and some titanium alloys show bioinertness due to the spontaneously generated non-reactive passive film (TiO ₂ oxide layer). The oxide layer (TiO ₂ ) basically has the advantage of preventing the biodegradation of the implant in a poor living environment, but has a disadvantage in that it takes a long time for bone union to occur due to bioinertness. It may take several months or more depending on the treatment environment when the mini screw is inserted for orthodontic treatment. In addition, in the case of patients with congenitally weak bones or elderly patients, there are also individual differences between patients in actual clinical practice.

Conventional Korean Patent Application Laid-Open No. 2019-0003266 discloses an orthodontic miniscrew in which a number of pores are formed by sand-blasted, large-grit, acid-etched (SLA) treatment on the body surface, but the surface treatment of the SLA method is not Although there is an aspect of increasing the surface energy by increasing the surface area at the micron level, there is a limit to securing the fixation force in the miniscrew that requires rapid bone formation because the oxide layer covering the surface layer is basically inert to the body.

Therefore, in the case of dental and orthopedic implants as well as orthodontic miniscrews that require close retention with bone in a short period of time, the surface of the screw is made of a nanotube structure to obtain excellent initial fixation, so that bioactive materials In addition, it is required to suppress the function of osteoclasts affecting the initial bone resorption around the implantation site or to promote the activity of osteoblasts that induce the generation of new bone.

Korea Patent Publication No. 2019-0003266 (published on 2019.01.09.)

One object of the present invention is to provide a mini-screw for orthodontic treatment that mechanically suppresses initial shake and frequent drop-off of the screw by forming a flute to increase the surface area and mechanical retention while reducing the body length of the screw and increasing the diameter, and a method for manufacturing the same. will provide

Another object of the present invention is to induce rapid osseointegration by forming a dense and strong calcium phosphate layer showing bioactivity on the surface by anodizing to form a nanotube TiO ₂ layer and then surface-treating it using a calcification cycle treatment technique. By doing so, it relates to a method of surface treatment that enables early loading.

Another object of the present invention is to mount strontium ranelate, which suppresses bone resorption of dense bone and promotes bone formation, to increase the initial holding power of the mini-screw implantation part, so that the mini-screw made of titanium is implanted when the mini-screw is implanted in human bone. An object of the present invention is to provide a miniscrew for orthodontic treatment that inhibits the decrease in initial fixation force by suppressing the initial bone resorption around the bone and induces rapid bone union by promoting the activity of osteoblasts and a method for manufacturing the same.

An object of the present invention is a head portion and a body integrally formed with the head portion, comprising a screw portion and a thread protruding from the surface of the screw portion, wherein the surface of the head portion and the body is a plurality of titanium dioxide nanotube layers and an apatite-phase calcium phosphate layer formed on the titanium dioxide nanotube layer, wherein strontium ranelate is mounted on the calcium phosphate layer.

According to a preferred feature of the present invention, the body has an average diameter of 1.4 to 3 millimeters, and a length of 3.3 to 8.0 millimeters, and a flute that is a vertical groove with respect to the transverse direction of the threaded body is formed.

According to a more preferred feature of the present invention, the titanium dioxide nanotube layer has a diameter of 200 to 500 nanometers and an average length of 500 to 2000 nanometers.

According to a more preferred feature of the present invention, the thickness of the calcium phosphate layer is 1 to 5 micrometers.

Another object of the present invention is to anodize the miniscrew to form a titanium dioxide nanotube layer on the surface of the miniscrew, and to circulate on the surface of the miniscrew on which the titanium dioxide nanotube layer is formed through the anodization step. A calcium phosphate layer forming step of forming a calcium phosphate layer by treatment and heat treatment at 400 to 600° C. to form a calcium phosphate layer on apatite for removal of impurities and stabilization of the calcium phosphate layer, and strontium in the calcium phosphate layer formed on the surface It can also be achieved by providing a method of manufacturing the orthodontic miniscrew, characterized in that it comprises a drug filling step of loading ranelate.

According to a preferred feature of the present invention, between the anodizing step and the calcium phosphate layer forming step, there is a silica solution treatment step of immersing the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step in an aqueous silica solution and then drying it. make it more advanced.

According to a more preferred feature of the present invention, in the calcium phosphate layer forming step, the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step is immersed in an aqueous sodium hydrogen phosphate solution, dried, and then the process of immersing in an aqueous calcium hydroxide solution is repeated. to be done by

According to a more preferred feature of the present invention, the immersion in the sodium hydrogen phosphate aqueous solution shall be made for 30 to 90 seconds at a temperature of 80 to 100 ℃.

According to an even more preferred feature of the present invention, the immersion in the aqueous calcium hydroxide solution shall be made for 30 to 90 seconds at a temperature of 80 to 100 ℃.

According to an even more preferred feature of the present invention, the repetition is assumed to consist of 20 to 30 times.

According to an even more preferred feature of the present invention, in the drug filling step, the miniscrew having a calcium phosphate layer formed through the calcium phosphate layer forming step is immersed in an aqueous or acidic solution containing strontium ranelate and freeze-dried 1 to 10. It shall be repeated several times or more.

The orthodontic miniscrew and its manufacturing method according to the present invention reduce the length of the body and increase the diameter while forming the flute to increase the specific surface area, thereby maximizing the mechanical holding force with the bone to prevent the initial shaking and frequent loosening of the screw. It represents providing a mini screw for calibration.

In addition, after anodizing, the surface is treated with the calcification cycle treatment technique to form a dense and firmly attached bioactive calcium phosphate layer, and strontium ranelate, which inhibits bone resorption and promotes formation, is filled with the titanium material mini. It has an excellent effect of providing an orthodontic mini-screw that dramatically improves the success rate of orthodontic surgery by preventing the more active osteoclast activity when the screw is inserted into human bone and further promoting the bioactivity of the titanium implant and bone.

1 is a cross-sectional view showing a mini-screw for calibration according to the present invention.
2 is a flowchart illustrating a method of manufacturing the orthodontic mini-screw according to an embodiment of the present invention.
3 is a flowchart illustrating a method of manufacturing a mini-screw for correction according to another embodiment of the present invention.
4 to 5 are images of the surfaces of the miniscrews prepared in Example 1 and Comparative Examples 3 to 4 of the present invention by FE-SEM, and the element concentration present on the surface of the miniscrew is measured using an energy dispersive X-ray spectrometer. (EDS) is a picture analyzed and shown.
6 to 7 are images of the surfaces of the miniscrews prepared in Example 2 and Comparative Examples 5 to 6 of the present invention by FE-SEM, and the element concentration present on the surface of the miniscrew was measured using an energy differential spectrometer (EDS). This is a picture that has been analyzed.
8 is a graph showing the surface components of the miniscrews prepared in Example 1 and Comparative Examples 1 to 4 of the present invention measured by XRM.
9 is a graph showing fracture torque values of miniscrews manufactured according to Example 1 and Comparative Examples 3 to 4 of the present invention after installation.

Hereinafter, a preferred embodiment of the present invention and the physical properties of each component will be described in detail, which is intended to describe in detail enough that a person of ordinary skill in the art to which the present invention pertains can easily carry out the invention, This does not mean that the technical spirit and scope of the present invention is limited.

As shown in FIG. 1 below, the orthodontic mini-screw according to the present invention is formed integrally with a head part and the head part, and consists of a body including a screw part and a thread protruding from the surface of the screw part.

The body includes a screw portion and a screw thread protruding from the surface of the screw portion, and by forming a flute on the surface, it is possible to increase the mechanical holding force. In addition, by providing a differentiated surface treatment technology compared to the existing miniscrews, it has excellent bioactivity, so that when it is implanted in relatively thin areas such as the palatine bone, tooth root, and gums, it is seated in a short time, so it is not shaken at the beginning and fast fixing power can be secured. there is. In addition, a calcium phosphate layer is formed by performing calcification cycle treatment on the titanium dioxide nanotube layer, impurities are removed through heat treatment, and the calcium phosphate layer is stabilized to induce precipitation of bone-like apatite. In addition, by depositing a bone-like calcium phosphate layer on the titanium dioxide nanotube layer and loading a strontium ranelate drug on the surface, the function of osteoclasts is suppressed before the miniscrew is stabilized in the initial stage of implantation, thereby maintaining the retention power due to weakening of the bone around the implantation site. It is possible to dramatically increase the success rate (%) by increasing the generation of new bone by promoting the reduction and activation of osteoblasts.

Further, the body has an average diameter of 1.8 to 3 millimeters and a length of 3 to 8 millimeters.

The material of the miniscrew may be titanium or a titanium alloy that satisfies a bioactive function and can secure initial fixability.

The surface of the miniscrew may be coated with a plurality of titanium oxide nanotube layers and a calcium phosphate layer formed on the titanium dioxide nanotube layer to improve biocompatibility. The titanium dioxide (TiO ₂ ) nanotube layer has a plurality of uniformly protruding shapes on the surface of the miniscrew, and may serve to prevent the decomposition of the implant in the patient's living body or inside the bone.

The titanium dioxide nanotube layer may have a thickness of 200 to 500 nanometers, an average length of the tube of 500 to 2000 nanometers, and an average outer diameter of 60 to 180 nanometers.

The titanium dioxide nanotube layer may be advantageous in precipitation of calcium phosphate when the average diameter of the outer diameter is increased. Conversely, when the titanium dioxide nanotube layer has a length of 2000 nanometers or more, the surface-treated film layer may be excessively damaged during the mini-screw installation process.

If the thickness of the calcium phosphate layer is less than 5 micrometers, the calcium phosphate layer deposited by surface treatment during the insertion of the miniscrew is not significantly damaged, and the calcium phosphate deposited inside the flute is not damaged during the placement process, so that the initial fixing force is increased. can induce

The calcium phosphate layer may be formed on the inner, outer, and peripheral surfaces of the titanium dioxide nanotube layer, and penetrate into the titanium dioxide nanotube layer and densely precipitate to promote bioactivity. In addition, when strontium ranelate is mounted on the titanium dioxide nanotube layer without calcium phosphate precipitation, the function of osteoclast itself is reduced and osteoblast activity is increased to suppress bone resorption, thereby promoting new bone formation. .

The strontium ranelate inhibits the differentiation of osteoclasts from osteoclasts into osteoclasts, suppresses osteoclast bone resorption, and promotes osteoblast proliferation and differentiation into osteoblasts, resulting in inhibition of bone resorption. and osteogenesis promoting effect at the same time.

In addition, the method for manufacturing the orthodontic miniscrew according to the present invention includes an anodizing step (S101) of anodizing the miniscrew to form a titanium dioxide nanotube layer on the surface of the miniscrew, and the anodizing step (S101). Strontium ranel is formed on the calcium phosphate layer formed on the surface of the miniscrew through the calcium phosphate layer forming step (S103) and the calcium phosphate layer forming step (S103) of forming a calcium phosphate layer on the surface of the miniscrew on which the titanium dioxide nanotube layer is formed. It consists of a drug filling step (S105) of charging the rate.

The anodizing step (S101) is a step of anodizing the miniscrew to form a titanium dioxide nanotube layer on the surface of the miniscrew, wherein the miniscrew is formed on the body surface as described in the orthodontic miniscrew. A flute can be formed on the surface. Using a CNC automatic lathe (cincom L20), the average diameter of the body is 1.8 to 3 millimeters, the length is 2 to 3.5 millimeters, and it can be machined in a form in which a flute is formed on the surface. there is.

The step of forming the titanium dioxide nanotube layer on the surface of the mini-screws in the anodizing step (S101) is to immerse the fluted mini-screw and the negative electrode in an electrolyte solution through the same process as above, and then anodize the mini-screw. The titanium dioxide nanotube layer may be formed by anodizing the entire or threaded portion of the miniscrew on which the flute is formed.

The anodic oxidation has the advantage of shortening the manufacturing time because it is simple compared to other methods. The anodic oxidation can be oxidized by reaching a final voltage of 10 to 40 V at a current density of 5 to 50 mA/cm 2 in constant voltage and constant current mode, and maintaining the final voltage for 5 minutes to 2 hours. The anodic oxidation may be performed by using titanium or a titanium alloy as an anode and using one selected from the group consisting of platinum (Pt), tungsten (W) and silver (Ag) as a cathode to oxidize the anode in an electrolyte solution.

The electrolyte solution is one selected from the group consisting of glycerol (glycerol), hydrofluoric acid (HF), ammonium fluoride (NH ₄ F) acid ammonium fluoride (NH ₄ HF ₂ ), sodium fluoride (NaF) and water (H ₂ O) More than one species can be used. Preferably, it may be at least one selected from the group consisting of glycerol (glycerol), ammonium fluoride (NH ₄ F) and water (H ₂ O), most preferably glycerol (glycerol), ammonium fluoride (NH ₄ F) and water (H ₂ O). The mixture is made by mixing 0.3 to 2 parts by weight of ammonium fluoride (NH ₄ F) and 5 to 30 parts by weight of water (H ₂ O) to 100 parts by weight of glycerol, wherein the mixing amount of ammonium fluoride (NH ₄ F) is 0.3 When it is less than 2 parts by weight or more than 2 parts by weight, the structure of the formed nanotube layer may be incomplete.

In addition, if the amount of water (H ₂ O) is less than 5 parts by weight, the diameter of the nanotube layer may be excessively reduced, and if it exceeds 30 parts by weight, the length compared to the diameter of the nanotube layer becomes too long, so that when implantation is performed, nano Damage to the tube layer may occur.

In the anodic oxidation, the negative electrode may be one selected from the group consisting of platinum (Pt), tungsten (W) and silver (Ag), but if it is a negative electrode used for general anodization, there is no limitation on its use.

The distance between the positive electrode and the negative electrode may be 10 to 50 mm, preferably 20 to 30 mm, and the voltage may be 10 to 50 V. In addition, the reaction time of the anodization may be 10 to 180 minutes, and preferably, the electrochemical reaction may be performed for 30 to 60 minutes to form a plurality of protruding titanium dioxide nanotube layers on the surface of the miniscrew. In addition, in order to smoothly form the titanium dioxide nanotube layer and improve the structure, the miniscrew may be rotated or moved left and right during oxidation treatment.

The calcium phosphate layer forming step (S103) is a step of forming a calcium phosphate layer on the surface of the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step (S101), and the titanium dioxide nanotube formed on the surface of the miniscrew. It proceeds to make the layer more firm and dense and to improve bioactivity.

The calcium phosphate layer forming step (S103) is performed by repeating the process of immersing the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step (S101) in an aqueous sodium hydrogen phosphate solution, drying it, and then immersing it in an aqueous calcium hydroxide solution. , The immersion in the sodium hydrogen phosphate aqueous solution is preferably made at a temperature of 80 to 100 ℃ for 30 to 90 seconds, the immersion in the aqueous calcium hydroxide solution is preferably made for 30 to 90 seconds at a temperature of 80 to 100 ℃, The repetition is preferably made 20 to 30 times.

When the calcium phosphate layer is formed through the calcification cycle repeated 20 to 30 times as described above, it is preferable to perform a process of stabilizing the miniscrew having the calcium phosphate layer formed at a temperature of 450 to 550° C. for 1 to 3 hours. .

In addition, between the immersion in the sodium hydrogen phosphate aqueous solution and the immersion in the calcium hydroxide aqueous solution, the process of washing the miniscrew immersed in the sodium hydrogen phosphate aqueous solution in deionized water for 2 to 8 seconds may be further performed.

In addition, after the process of immersion in the aqueous calcium hydroxide solution, the miniscrew immersed in the aqueous calcium hydroxide solution before being immersed in the aqueous sodium hydrogen phosphate solution may be further washed in deionized water for 2 to 8 seconds.

After immersion in sodium hydrogen phosphate aqueous solution as described above, the process of immersion in calcium hydroxide aqueous solution is repeated 20 to 30 times. activity can be increased. At this time, if the number of the continuous process is less than 20 times, the calcium phosphate layer may not be formed evenly on the surface of the titanium dioxide nanotube layer. Charging can be difficult.

In addition, the stabilization process may be performed in order to create a condition in which the strontium ranelate drug can be filled in the miniscrew on which the calcium phosphate layer is formed, and to remove impurities.

The drug filling step (S105) is a step of filling the calcium phosphate layer formed on the surface of the miniscrew through the calcium phosphate layer forming step (S103) with strontium ranelate. Preferably, the miniscrew having the calcium layer formed thereon is immersed in an aqueous solution of 1 to 10 mg/mL of strontium ranelate and then dried by repeating the process 5 to 7 times.

In addition, between the anodizing step (S101) and the calcium phosphate layer forming step (S103), the miniscrew having the titanium dioxide nanotube layer formed through the anodizing step (S101) is immersed in an aqueous silica solution and then dried in an aqueous silica solution The treatment step (S102) may be further proceeded, and the miniscrew on which the titanium dioxide nanotube layer is formed through the anodization step (S101) is placed in an aqueous silica solution having a mass concentration of 0.5% for 4 to 6 minutes, preferably for 5 minutes. After immersion, it consists of a process of drying for at least 1 hour in an electric heater (OF-12GW, Jeio Tech, Daejeon, Korea) maintained at a temperature of 37°C.

Hereinafter, the method for manufacturing the orthodontic miniscrew according to the present invention and the physical properties of the orthodontic miniscrew manufactured through the manufacturing method will be described with reference to examples.

<Example 1>

(1) Manufacture of mini screw with flutes formed on the body surface

Using a Ti-6Al-4V ELI alloy rod (KodentInc, DBA TMS, USA), a miniscrew specimen having an average diameter of 0.5 mm, a length of 265 mm, a body diameter of 24 mm, and a length of 35 mm produced. Then, one flute was formed on the miniscrew body using a CNC automatic lathe (cincom L20), and the width of the groove was 1 mm and the length in the longitudinal direction was 17 mm.

(2) Anodizing treatment

In order to remove the oxide film layer formed on the surface of the flute-formed miniscrew specimen prepared in (1) above, the miniscrew specimen was immersed in a solution consisting of 12 parts by weight of HNO ₃ , 7 parts by weight of HF, and the remaining amount of purified water for 10 seconds. After washing and drying, anodizing for 60 minutes at a voltage of 20 V and a current density of 20 mA/cm 2 in a glycerol solution containing 20% by weight of purified water and 1.5% by weight of NH ₄ F, the positive electrode The oxidized miniscrew specimen was ultrasonically cleaned in tertiary distilled water for 1 minute and then dried in a dryer at 50° C. for 24 hours.

On the surface of the anodized miniscrew, a titanium dioxide nanotube layer having a thickness of 350 nm, an average length of 760 nm, and an average outer diameter of 110 nm was formed.

(3) Low-temperature calcification cycle treatment

The miniscrew with the titanium dioxide nanotube layer formed through the anodization treatment in (2) above was added to 3 g/500 mL of 0.05M NaH ₂ PO ₄ aqueous solution and 0.41 g/500 mL of 0.0077M Ca(OH) ₂ aqueous solution at 90° C. for 1 minute, respectively. Cyclic pre-calcification treatment was performed for 20 times in a periodic deposition method. After the calcification cycle treatment, an 80 nm-thick calcium phosphate layer was formed on the titanium dioxide nanotube layer of the miniscrew. Then, the mini-screw with the calcium phosphate layer formed thereon was put into an electric furnace (Ajeon Industrial Co, Ltd, Korea), heated to 500°C at a temperature increase rate of 10°C/min, and maintained for 2 hours to achieve structural stabilization and to remove impurities. did

(4) Immersion of strontium ranelate drug

After diluting strontium ranelate to a concentration of 2 mg/mL in distilled water, the miniscrew with the calcium phosphate layer formed thereon was immersed in the diluted drug for 10 minutes, and the process of freeze-drying with nitrogen gas was repeated 6 times to obtain strontium ranelate. Calibration miniscrews filled with was prepared.

<Example 2>

Proceed in the same manner as in Example 1, except that in (3), a 0.0099M Ca(OH) ₂ aqueous solution was used, and in (4), strontium ranelate was diluted to a concentration of 3 mg/mL in distilled water to obtain strontium ranelate. Calibration miniscrews filled with was prepared.

<Comparative Example 1>

Untreated miniscrews that were not subjected to anodic oxidation and calcification cycle treatment were prepared.

<Comparative Example 2>

A mini screw was manufactured in the same manner as in Example 1, except that no calcification cycle treatment was performed after anodization.

<Comparative Example 3>

A mini screw was prepared in the same manner as in Example 1, except that strontium ranelate was not charged after the calcification cycle treatment.

<Comparative Example 4>

After the titanium dioxide nanotube layer was formed on the surface of the miniscrew of Comparative Example 2, 0.05M NH ₄ H ₂ PO ₄ aqueous solution and Ca(OH) ₂ and Sr(OH) ₂ were mixed in an aqueous solution of 0.0077:0.0033 20 A miniscrew having a calcium phosphate layer formed thereon was prepared by cyclic cycle treatment.

<Comparative Example 5>

A mini screw was prepared in the same manner as in Example 2, except that strontium ranelate was not charged after the calcification cycle treatment.

<Comparative Example 6>

After forming the titanium dioxide nanotube layer on the surface of the miniscrew of Comparative Example 2, 0.05M NH ₄ H ₂ PO ₄ aqueous solution and Ca(OH) ₂ and Sr(OH) ₂ were mixed in an aqueous solution of 0.0099:0.0011 20 A miniscrew having a calcium phosphate layer formed thereon was prepared by cyclic cycle treatment.

FE-SEM (Field Emission Scanning Electron Microscope, S4800, Hitachi, Japan) photos of the miniscrews prepared in Example 1 and Comparative Examples 3 to 4 were taken, and elements present on the screw surface The concentration was analyzed with an energy dispersive spectrometer (EDS) and shown in FIGS. 4 to 5 below.

As shown in FIGS. 4 to 5 below, it can be seen that in the miniscrews prepared in Examples 1 and 3 to 4 of the present invention, a calcium phosphate layer was formed on the titanium dioxide nanotube layer after low-temperature calcification cycle treatment.

In addition, FE-SEM (Field Emission Scanning Electron Microscope, S4800, Hitachi, Japan) of the miniscrews prepared in Example 2 and Comparative Examples 5 to 6 were photographed and present on the screw surface. The element concentration was divided by an energy dispersive spectrometer (EDS), and is shown in FIGS. 6 to 7 below.

As shown in FIGS. 6 to 7 below, it can be seen that the miniscrews prepared in Example 2 and Comparative Examples 5 to 6 of the present invention had a calcium phosphate layer formed on the titanium dioxide nanotube layer after low-temperature calcification cycle treatment.

In addition, the components of the miniscrews of Example 1 and Comparative Examples 1 to 4 were measured by XRM and are shown in FIG. 8 below.

{(a) Comparative Example 1, (b) Comparative Example 2, (c) Comparative Example 3, (d) Comparative Example 4, (e) Example 1}

As shown in FIG. 8 below, in Example 1 of the present invention, strontium ranelnate was mainly concentrated on the surface layer, so that the Sr peak was observed. (d) In Comparative Example 4, strontium ranelnate was dispersed throughout the surface layer. Therefore, it can be seen that the Sr peak is not observed.

In addition, the miniscrews prepared in Example 1 and Comparative Examples 3 to 4 were placed in the tibia of both sides of male rats (Wistar rats; 12 weeks old) weighing 200 to 225 g, and the fracture torque value was measured in the figure below. 9 is shown.

{However, the implantation is performed under general anesthesia by exposing the full-thickness valves on the inner side of the diaphysis of both sides to form a bicortical implant bed, and then placing it through a self-tapping process until the screw thread is seated in the cortical bone. , After suturing with absorbable sutures, and after oral administration of antibiotics and anti-inflammatory drugs, 9 animals were sacrificed after 2 and 4 weeks, respectively, by overdosing with thiopental.

After sacrificing rats at the 2nd and 4th weeks of implantation, the implanted part was exposed, the implanted part was fixed, a digital torque gauge was connected, and the fracture torque value of the bonding interface was measured by turning it counterclockwise.}

As shown in FIG. 9 below, it can be seen that the miniscrew manufactured according to Example 1 of the present invention exhibited excellent fracture torque values after implantation, which shows that Example 1 exhibited excellent osseointegration under the same conditions. will be.

Therefore, the orthodontic miniscrew and its manufacturing method according to the present invention maximize the bioactivity with bone and prevent the initial shaking and frequent loosening of the screw by increasing the specific surface area by forming a flute while reducing the body length and increasing the diameter. A mini screw for calibration is provided.

In addition, after anodizing, the surface is treated with a low-temperature calcification cycle treatment technique to form a dense and strong calcium phosphate layer, and strontium ranelate, which inhibits bone resorption and promotes formation, is filled with the titanium material miniscrew to human bones. It prevents the activity of osteoclasts that become more active when implanted, and further improves the success rate of orthodontic treatment by promoting the bioactivity of the titanium implant and bone.

S101; anodization step
S102; Silica aqueous solution treatment step
S103; Calcium phosphate layer formation step
S105 ; drug filling stage

Claims (11)

delete delete delete delete anodizing step of anodizing the miniscrew to form a titanium dioxide nanotube layer on the surface of the miniscrew;
Silica solution treatment step of immersing the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step in an aqueous silica solution and then drying
Forming a calcium phosphate layer on the surface of the dried miniscrew after immersion in an aqueous silica solution through the silica aqueous solution treatment step, removing impurities and stabilizing the formed calcium phosphate layer, and forming a calcium phosphate layer for inducing precipitation of apatite; and
and a drug filling step of loading strontium ranelate on the calcium phosphate layer formed on the surface of the miniscrew through the calcium phosphate layer forming step. delete 6. The method of claim 5,
The calcium phosphate layer forming step is performed by repeating the process of immersing the miniscrew on which the titanium dioxide nanotube layer is formed through the anodizing step in an aqueous sodium hydrogen phosphate solution, drying it, and then immersing it in an aqueous calcium hydroxide solution. Screw manufacturing method. 8. The method of claim 7,
A method of manufacturing a miniscrew for correction, characterized in that the immersion in the sodium hydrogen phosphate aqueous solution is performed at a temperature of 80 to 100° C. for 30 to 90 seconds. 8. The method of claim 7,
A method of manufacturing a miniscrew for correction, characterized in that the immersion in the aqueous calcium hydroxide solution is performed at a temperature of 80 to 100° C. for 30 to 90 seconds. 8. The method of claim 7,
The method of manufacturing a miniscrew for correction, characterized in that the repetition is made up of 20 to 30 times. 6. The method of claim 5,
In the drug filling step, the miniscrew having a calcium phosphate layer formed through the calcium phosphate layer forming step is immersed in 1 to 10 mg/mL of strontium ranelate aqueous solution or an acidic aqueous solution, followed by drying by repeating the process 5 to 7 times. A method of manufacturing a mini-screw for orthodontic treatment, characterized in that.

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