Sand particle residue-free surface porous super-hydrophilic implant and preparation method thereof

Abstract

The present application relates to the field of medical devices, and discloses a surface layer porous super-hydrophilic implant without sand residue and a preparation method thereof. The implant comprises an implant base with a porous structure on the surface layer, and a porous hydroxyapatite film formed on the surface of the implant base and the porous structure. The present application first forms micropores with large pore diameters on the surface layer of the implant base, and then constructs a porous hydroxyapatite film with nanochannels on the surface of the implant base and the large micropores. The nanochannels are connected to each other, and a fiber-like concave-convex micro-nano surface structure with ideal roughness is constructed, which has the advantages of good bone tissue combination, good corrosion resistance, and prevention of metal ion release in the implant. The implant base is directly anodized after sand blasting and simple cleaning, and through process optimization, a porous titanium dioxide film can be formed on the surface of the implant base and the porous structure, and the sand particles can be completely removed without acid etching treatment.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to a porous, superhydrophilic implant with no sand particles remaining on the surface and its preparation method. Background Technology

[0002] An implant is a man-made implant that is inserted into the jawbone to support the superstructure of a prosthesis. Also known as an artificial tooth root, an implant is surgically placed into the jawbone at the site of the missing tooth. Once implanted, it remains stationary and replaces the root of a dislodged or extracted tooth.

[0003] Currently, implants are mainly made of pure titanium or titanium alloys. To increase the contact area between the implant and bone tissue and enhance the bonding strength, existing technologies require implants to undergo surface treatment, typically including degreasing, sandblasting, ultrasonic cleaning, acid etching, and rinsing. Degreasing removes residual oil from the implant surface after machining, facilitating subsequent processing; sandblasting uses abrasive particles (usually alumina particles) to impact the implant surface, creating irregular, rough concave surfaces of 10-30µm; ultrasonic cleaning removes abrasive particles adhering to the implant surface after sandblasting; and acid etching ensures the formation of smaller, rougher concave surfaces of 1-4µm, while further removing any remaining abrasive particles after ultrasonic cleaning. However, the above surface treatment processes have the following shortcomings:

[0004] (1) Cleaning the implant after sandblasting is crucial. If sand particles introduced by sandblasting remain in the implant, it can easily lead to inflammation or implant detachment. However, because the sand particles are small, they can penetrate deep into the rough concave surface during sandblasting, making them difficult to remove completely. The existing "ultrasonic cleaning + acid etching" method still cannot completely remove residual sand particles from the implant.

[0005] (2) Currently, the acids used for acid etching generally include hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, etc. Among them, nitric acid, hydrochloric acid, and hydrofluoric acid are highly volatile, and the acid etching temperature needs to be greater than 60°C and the acid etching time is relatively long, which further promotes the volatilization of the acid. This is not only detrimental to personnel health and equipment maintenance, but also causes serious environmental pollution due to the large amount of acid discharged.

[0006] (3) The traditional rough surface of titanium implants increases the dissolution rate of titanium ions and reduces the biocompatibility of the implants.

[0007] (4) After sandblasting and acid etching, the hydrophilicity of the implant is unstable. If it is placed in the air to dry after the surface treatment is completed, it is easy to become hydrophobic due to the contamination of carbohydrates in the air, resulting in poor biological activity. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides a porous, superhydrophilic implant with no residual sand particles and its preparation method. This invention first forms large-diameter micron-sized pores on the surface of the implant substrate, and then constructs a porous hydroxyapatite film with nanopores on the surface of the implant substrate and the pore channels of these micron-sized pores. These interconnected nanopores form a fibrous, undulating micro / nano surface structure with ideal roughness, achieving an ideal rough surface form and surface roughness for the dental implant, good bone tissue integration, and good corrosion resistance, preventing the release of metal ions from the implant. This invention allows for direct anodizing of the implant substrate after sandblasting and simple cleaning. Through process optimization, a porous titanium dioxide film can be formed on the surface of the implant substrate and the porous structure surface, completely removing sand particles without acid etching.

[0009] The specific technical solution of this invention is as follows:

[0010] In a first aspect, the present invention provides a surface porous superhydrophilic implant without sand particles, comprising an implant matrix with a porous surface structure, and a porous hydroxyapatite membrane formed on the surface of the implant matrix and the porous structure.

[0011] The implant of this invention is essentially free of sand particles, reducing the risk of inflammation and implant detachment, and is highly safe.

[0012] Furthermore, this invention first forms large-diameter micron-sized pores on the surface of the implant matrix, and then constructs a porous hydroxyapatite membrane with nanopores on the surface of the implant matrix and these micron-sized pores. These nanopores are interconnected, forming a fibrous, uneven micro / nano surface structure with ideal roughness, which has the following advantages: (a) it greatly increases the specific surface area of ​​the porous hydroxyapatite membrane, which is a bioactive substance, and can effectively improve the bonding between bone tissue and implant; (b) it has good corrosion resistance, which can not only enhance the corrosion resistance of the implant in vivo, but also prevent the release of metal ions from the implant; (c) it has superhydrophilicity, is not easily polluted by air when exposed to air, and has high bioactivity.

[0013] Preferably, the implant substrate is made of pure titanium.

[0014] Secondly, the present invention provides a method for preparing the above-mentioned surface porous superhydrophilic implant without sand particles residue, comprising the following steps:

[0015] 1) Degreasing: Degreasing the implant substrate.

[0016] The surface of the implant substrate after machining usually has residual oil stains. Degreasing treatment is beneficial for subsequent steps.

[0017] 2) Sandblasting: The implant substrate is sandblasted to obtain an implant substrate with a porous structure of 10-30μm on the surface.

[0018] The strong impact of sand particles on the implant substrate creates a porous structure with large pores on its surface, laying the foundation for subsequent porous titanium dioxide membranes.

[0019] 3) Cleaning.

[0020] The implant substrate is simply cleaned to remove easily removable sand particles.

[0021] 4) Anodizing: The implant substrate is immersed in the electrolyte and anodized by sequentially applying reverse current-forward current-reverse current-forward current using a pulsed power supply, while simultaneously undergoing ultrasonic treatment to obtain a dental implant with a porous titanium dioxide film free of residual sand particles.

[0022] During the anodizing process, a special reverse current-forward current-reverse current-forward current method is employed, supplemented by ultrasonic treatment, to form a porous titanium dioxide film while thoroughly removing residual sand particles located deep within the porous structure. This interconnected porous titanium dioxide film exhibits a textured micro / nano structure, providing a foundation for calcium and phosphorus deposition.

[0023] 5) Cleaning.

[0024] 6) Calcium and phosphorus deposition: The implant substrate is immersed in an alkaline soluble phosphate solution at 20-30℃, and a soluble calcium salt solution at 20-30℃ is added dropwise. After standing, an implant substrate with calcium and phosphorus deposited on a porous titanium dioxide film of 20-100nm is obtained.

[0025] 7) Cleaning and drying: Wash the implant substrate with water and then vacuum dry it.

[0026] By cleaning away residual liquid after calcium and phosphorus deposition, this invention discovered that if implants are dried under air conditions, they easily become hydrophobic, leading to reduced bioactivity. Therefore, this invention employs vacuum drying to obtain a stable, superhydrophilic deposition layer.

[0027] 8) Alkaline treatment: The implant matrix is ​​placed in a sodium hydroxide solution for static reaction, which converts titanium dioxide into sodium titanate, resulting in an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure.

[0028] When a titanium dioxide film deposited with calcium and phosphorus is immersed in an alkaline solution, it reacts and transforms into a porous sodium titanate adhesive layer doped with calcium and phosphorus.

[0029] 9) Cleaning and drying: Wash the implant substrate with water and then vacuum dry it.

[0030] Cleaning is used to remove residual liquid. To reduce the contact between the implant and air, vacuum drying is used to obtain a stable superhydrophilic membrane.

[0031] 10) Heat treatment: The implant matrix is ​​heat treated to obtain an implant with a porous hydroxyapatite membrane, that is, a porous superhydrophilic implant with no sand particles remaining on the surface.

[0032] After heat treatment, the porous induced hydroxyapatite membrane is transformed into a more firmly bonded hydroxyapatite membrane.

[0033] As described in the background section of this application, to increase the contact area between the implant and bone tissue and enhance the bonding strength, the mainstream method currently is to perform surface sandblasting on the implant matrix. During sandblasting, the intense impact of the sand particles on the implant matrix creates an irregularly rough, concave surface (porous structure). Removing as many sand particles as possible in subsequent processing is crucial; if a large amount of sand particles remain in the implant, it can easily lead to inflammation or implant detachment. Currently, the common method is to reduce the amount of sand particles remaining through "ultrasonic cleaning + acid etching." However, because some sand particles have already penetrated deep into the porous structure during sandblasting, the existing "ultrasonic cleaning + acid etching" method still cannot completely remove the residual sand particles from the implant. The traditional rough surface of titanium implants increases the dissolution rate of titanium ions, reducing the biocompatibility of the implant. Furthermore, the acids currently used for acid etching are mainly highly volatile acids such as nitric acid, hydrochloric acid, and hydrofluoric acid, and the etching temperature needs to be above 60°C, which further promotes acid volatilization. This is not only detrimental to personnel health and equipment maintenance, but also causes serious environmental pollution due to the large amount of acid emitted. Therefore, the method of this invention abandons the traditional acid etching step. After sandblasting and simple water washing, the implant substrate is directly subjected to a special anodizing treatment. Through targeted adjustments to the anodizing process, a porous titanium dioxide film is formed on the surface of the implant substrate, completely removing sand particles without acid etching. Therefore, the method of this invention not only completely removes sand particle residue, but also does not use highly volatile acids throughout the entire process, making it safer and more environmentally friendly.

[0034] Furthermore, existing technologies typically involve air drying during surface treatment. However, this invention has found that implants dried in air tend to become hydrophobic, leading to reduced bioactivity. Therefore, this invention employs vacuum drying, resulting in a stable, superhydrophilic film with higher bioactivity.

[0035] Preferably, in step 4), the anodizing process is as follows:

[0036] First reverse current: reverse duty cycle 20-30%, frequency 90-110HZ, voltage 60-80V, time 5-10min, 25-30℃;

[0037] First forward current: forward duty cycle 20-30%, frequency 90-110HZ, voltage 60-80V, time 1-3s, 25-30℃;

[0038] Second reverse current: reverse duty cycle 20-30%, frequency 90-110HZ, voltage 120-130V, time 3-6min, 25-30℃;

[0039] Second forward current: forward duty cycle 20-100%, frequency 3000-10000HZ, voltage 100-120V, time 60-90min, 25-30℃.

[0040] Conventional anodizing processes can only form a titanium dioxide film, but cannot create an ideal rough micro / nano surface structure, nor can they completely remove sand particles. This invention achieves the above-mentioned technical effects through optimization of the anodizing process. The specific principle is as follows:

[0041] During the first reverse current treatment, ultrasonic treatment is used to preliminarily remove oil and surface impurities from the implant substrate. During the first short-term forward current treatment, hydrogen gas (generated during the first reverse current) diffuses into the metal. During the second reverse current treatment, the voltage is increased to ensure that a sufficient number of bubbles are precipitated, further removing residual sand particles. During the second forward current treatment, a titanium dioxide film with a nanoporous uneven structure is formed on the original micron-pore surface.

[0042] In the above process, this invention combines ultrasonic treatment with electric current action. Compared to ultrasonic treatment alone, it has a more significant removal effect on sand particles deeply embedded in the implant. The principle is as follows: ultrasonic cleaning utilizes the energy generated by ultrasonic frequency vibrations to produce microbubbles in the solution. This invention discovers that when combined with electric current action, these microbubbles can explode on the surface of the object, thereby achieving a more significant cleaning effect. On the other hand, the forward and reverse current anodizing process combined with ultrasound can stir the solution, allowing the electrolyte around the implant to flow better and ensuring that the surface receives fresh solution, which plays an auxiliary role in removing sand particles embedded in the pores.

[0043] Furthermore, it is important to emphasize that parameters such as voltage, current, and time at each stage require strict control. In the first reverse current stage, the voltage should be chosen to ensure a sufficient number of bubbles are generated, allowing oil to be detached from the implant surface; therefore, the voltage is relatively low. In the second reverse current stage, the main purpose is to remove sand particles embedded in the implant while ensuring no excessive corrosion; therefore, the voltage is relatively higher and the duration is shorter. Moreover, improper control of the anodizing process can affect the porous structure of the titanium dioxide film, resulting in insufficient surface roughness of the micro / nano structure, or causing the titanium dioxide to become too large, clogging the pores and preventing the formation of an interconnected pore structure.

[0044] Preferably, in step 4), the electrolyte comprises: 1-2 wt% sodium dihydrogen phosphate, 0.08-0.2 wt% NH4HF2, and the balance being water; the frequency of the ultrasonic treatment is 25-35 Hz.

[0045] As a preferred option, step 1) specifically includes: immersing the machined implant substrate in anhydrous ethanol for 3-7 minutes, followed by ultrasonic treatment with an oil-removing agent concentration of 0.3-0.7 vol%, a temperature of 70-80℃, a frequency of 25-35 Hz, and a time of 5-10 minutes.

[0046] As a preferred option, step 2) specifically includes: sandblasting the implant substrate with alumina sand particles, with a sandblasting pressure of 0.5-0.6MPa, a sandblasting distance of 8-12cm, and a time of 20-30s.

[0047] As a preferred option, step 3) specifically includes: soaking in water for 3-7 minutes, then rinsing for 8-12 seconds.

[0048] As a preferred option, step 5) specifically includes: first soaking in water for 2-4 minutes, then rinsing for 3-7 minutes, and finally spraying for 3-7 minutes.

[0049] As a preferred option, in step 6):

[0050] The concentration of the soluble phosphate solution is 0.036 mol / L, and the pH is 7.5-8.5; the concentration of the soluble calcium salt solution is 0.30 mol / L; after the addition is complete, the molar ratio of calcium to phosphorus is 1.6-1.7:1; the soluble phosphate is selected from potassium dihydrogen phosphate, sodium dihydrogen phosphate dihydrate, and ammonium dihydrogen phosphate; the soluble calcium salt is selected from calcium nitrate tetrahydrate, calcium chloride, calcium lactate, calcium acetate monohydrate, and calcium gluconate monohydrate.

[0051] Phosphates and calcium salts can only precipitate calcium phosphate under alkaline conditions. However, if the alkalinity is too high or the temperature is too high, the formed calcium phosphate layer is prone to instability.

[0052] Preferably, step 7) specifically includes: soaking in water for 1-3 minutes, then rinsing for 3-7 minutes, rinsing 2-4 times; vacuum drying at a temperature of 25-35℃ for 50-70 minutes.

[0053] Preferably, in step 8), the temperature of the sodium hydroxide solution is 50-60℃, the concentration is 4-6 mol / L, and the standing time is 4-6 h.

[0054] Preferably, in step 9), the water is first soaked for 1-3 minutes, then rinsed for 3-7 minutes, rinsed 2-4 times, and finally ultrasonically cleaned for 15-25 minutes at a temperature of 50-60℃ and a frequency of 25-35HZ; the vacuum drying temperature is 90-100℃ and the time is 30-50 minutes.

[0055] Preferably, step 10) specifically includes the following heat treatment:

[0056] A) The temperature rises from room temperature to 120°C in 25-35 minutes;

[0057] B) Heat to 360℃ in 25-35 minutes;

[0058] C) Heat to 600℃, taking 25-35 minutes;

[0059] D) Hold at 600℃ for 50-70 minutes;

[0060] E) Allow to cool naturally to 100°C.

[0061] Compared with the prior art, the beneficial effects of the present invention are:

[0062] (1) The present invention first forms micron-sized pores on the surface of the implant substrate, and then constructs a porous hydroxyapatite membrane with nanopores on the surface of the implant substrate and the surface of these micron-sized pores. These nanopores are interconnected, forming a fibrous undulating micro-nano surface structure with ideal roughness, which has the advantages of high specific surface area, good adhesion to bone tissue and good corrosion resistance, and can prevent the release of metal ions in the implant.

[0063] (2) The method of the present invention abandons the traditional acid etching step. After sandblasting and simple cleaning, the implant substrate is directly anodized. By making targeted adjustments to the anodizing process, a porous titanium dioxide film is formed on the surface of the implant substrate and the porous structure surface, and sand particles can be completely removed without acid etching. Therefore, the method of the present invention can not only completely remove sand particles, but also does not use strong volatile acids in the whole process, making it safer and more environmentally friendly.

[0064] (3) The present invention uses vacuum drying in the surface treatment process to obtain a stable superhydrophilic film layer with higher biological activity. Attached Figure Description

[0065] Figure 1 This is a SEM image of the surface of the implant substrate obtained after sandblasting in Example 1;

[0066] Figure 2 This is a SEM image of the surface of the implant substrate obtained after anodizing in Example 1;

[0067] Figure 3 Here is a surface SEM image of the implant obtained in Example 1;

[0068] Figure 4 Here is a SEM image of the surface of the implant obtained in Example 4;

[0069] Figure 5 Here is a surface SEM image of the final implant obtained in Comparative Example 1;

[0070] Figure 6 Here is a surface SEM image of the implant obtained in Comparative Example 2;

[0071] Figure 7 This is a SEM image of the surface of the final implant obtained in Comparative Example 4;

[0072] Figure 8 This is a SEM image of the surface of the final implant obtained in Comparative Example 5.

[0073] Figure 9 This is the EDS analysis spectrum of the implant matrix after anodizing in Example 1;

[0074] Figure 10 The image shows the EDS analysis spectrum of the implant obtained in Example 1.

[0075] Figure 11 The image shows the EDS analysis spectrum of the final implant obtained in Comparative Example 1.

[0076] Figure 12 The image shows the EDS analysis spectrum of the final implant obtained in Comparative Example 2;

[0077] Figure 13 The EDS analysis spectrum of the final implant obtained in Comparative Example 3;

[0078] Figure 14 The results of the surface hydrophilicity test of the final implant obtained in Example 1;

[0079] Figure 15 The results of the surface hydrophilicity test of the final implant obtained in Comparative Example 1;

[0080] Figure 16 The results of the surface hydrophilicity test of the final implant obtained in Comparative Example 2;

[0081] Figure 17 The results of the surface hydrophilicity test of the final implant obtained in Comparative Example 6 are shown. Detailed Implementation

[0082] The present invention will be further described below with reference to embodiments.

[0083] General Implementation Examples

[0084] A porous, superhydrophilic implant with no sand residue includes an implant matrix (preferably pure titanium) with a porous surface structure, and a porous hydroxyapatite membrane formed on the surface of the implant matrix and the porous structure.

[0085] A method for preparing the above-mentioned porous superhydrophilic implant with no sand residue includes the following steps:

[0086] 1) Degreasing: Immerse the machined implant substrate in anhydrous ethanol for 3-7 minutes, and then perform ultrasonic treatment. The concentration of the degreasing agent MIR-90 is 0.3-0.7 vol%, the temperature is 70-80℃, the frequency is 25-35HZ, and the time is 5-10 minutes.

[0087] 2) Sandblasting: Alumina sand particles are used to sandblast the implant substrate. The sandblasting pressure is 0.5-0.6MPa, the sandblasting distance is 8-12cm, and the time is 20-30s, resulting in an implant substrate with a porous structure of 10-30um on the surface.

[0088] 3) Cleaning: Soak the implant substrate in water for 3-7 minutes, then rinse for 8-12 seconds.

[0089] 4) Anodizing: The implant substrate is immersed in an electrolyte (1-2wt% sodium dihydrogen phosphate, 0.08-0.2wt% NH4HF2, balance water) and anodized using a pulse power supply, while simultaneously undergoing ultrasonic treatment (frequency 25-35 Hz) to obtain an implant substrate with thoroughly removed sand particles and a porous titanium dioxide film formed on the surface and porous structure.

[0090] The anodizing process is as follows: First reverse current: reverse duty cycle 20-30%, frequency 90-110 Hz, voltage 60-80 V, time 5-10 min, 25-30℃; First forward current: forward duty cycle 20-30%, frequency 90-110 Hz, voltage 60-80 V, time 1-3 s, 25-30℃; Second reverse current: reverse duty cycle 20-30%, frequency 90-110 Hz, voltage 120-130 V, time 3-6 min, 25-30℃; Second forward current: forward duty cycle 20-100%, frequency 3000-10000 Hz, voltage 100-120 V, time 60-90 min, 25-30℃.

[0091] 5) Cleaning: Soak the implant substrate in water for 2-4 minutes, rinse for 3-7 minutes, and finally spray for 3-7 minutes.

[0092] 6) Calcium and phosphorus deposition: Immerse the implant substrate in an alkaline soluble phosphate solution (concentration 0.03-0.04mol / L, pH=7.5-8.5) at 20-30℃, and add a soluble calcium salt solution (concentration 0.25-0.35mol / L) at 20-30℃ dropwise until the molar ratio of calcium to phosphorus is 1.6-1.7:1. Let it stand to obtain an implant substrate with calcium and phosphorus deposited on a porous titanium dioxide film of 20-100nm.

[0093] Preferably, the soluble phosphate is selected from potassium dihydrogen phosphate, sodium dihydrogen phosphate dihydrate, and ammonium dihydrogen phosphate; the soluble calcium salt is selected from calcium nitrate tetrahydrate, calcium chloride, calcium lactate, calcium acetate monohydrate, and calcium gluconate monohydrate.

[0094] 7) Cleaning and drying: Soak the implant substrate in water for 1-3 minutes, then rinse for 3-7 minutes, repeat rinsing 2-4 times; vacuum dry at 25-35℃ for 50-70 minutes.

[0095] 8) Alkaline treatment: The implant matrix is ​​placed in a sodium hydroxide solution with a concentration of 4-6 mol / L at 50-60℃ for 4-6 hours to react, so that titanium dioxide is converted into sodium titanate, and an implant matrix with a calcium phosphorus-doped porous sodium titanate adhesive layer formed on the surface and the porous structure surface is obtained.

[0096] 9) Cleaning and drying: Soak the implant substrate in water for 1-3 minutes, then rinse for 3-7 minutes, rinse 2-4 times, and finally ultrasonically clean for 15-25 minutes at a temperature of 50-60℃ and a frequency of 25-35HZ; vacuum dry at 90-100℃ for 30-50 minutes.

[0097] 10) Heat treatment: The implant substrate is heat treated, specifically including: A) heating from room temperature to 120℃ for 25-35 min; B) heating to 360℃ for 25-35 min; C) heating to 600℃ for 25-35 min; D) holding at 600℃ for 50-70 min; E) naturally cooling to 100℃; after heat treatment, an implant substrate with a porous hydroxyapatite film formed on the surface and porous structure is obtained, that is, a porous superhydrophilic implant with no sand particles remaining on the surface.

[0098] Specific embodiments and comparative examples

[0099] Example 1

[0100] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0101] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0102] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0103] 4) Anodizing: The implant substrate is immersed in an electrolyte (1wt% sodium dihydrogen phosphate, 0.08wt% NH4HF2, the balance being water) and anodized using a pulse power supply, while simultaneously undergoing ultrasonic treatment (frequency 30HZ) to obtain an implant substrate with thoroughly removed sand particles and a porous titanium dioxide film formed on the surface and porous structure.

[0104] The anodizing process is as follows:

[0105] First reverse current: reverse duty cycle 20%, frequency 100HZ, voltage 60V, time 10min, 25℃;

[0106] First forward current: forward duty cycle 20%, frequency 100HZ, voltage 60V, time 3s, 25℃;

[0107] Second reverse current: reverse duty cycle 20%, frequency 100HZ, voltage 120V, time 6min, 25℃;

[0108] Second forward current: forward duty cycle 100%, frequency 10000HZ, voltage 100V, time 90min, 25℃.

[0109] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0110] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 100 mL of potassium dihydrogen phosphate solution (concentration 0.036 mol / L, pH=8.0) at 25℃, slowly add 20 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃, let stand, and obtain an implant substrate with calcium and phosphorus deposited on a porous titanium dioxide film of 20-100 nm.

[0111] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0112] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60°C for 5 hours to react and convert titanium dioxide into sodium titanate, resulting in an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure.

[0113] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0114] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0115] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0116] B) Heat to 360℃ in 3 minutes;

[0117] C) Heat to 600℃ in 3 minutes;

[0118] D) Hold at 600℃ for 60 minutes;

[0119] E) Allow to cool naturally to 100°C;

[0120] After heat treatment, an implant matrix with a porous hydroxyapatite film formed on the surface and porous structure is obtained, which is a surface porous superhydrophilic implant without sand particles.

[0121] Example 2

[0122] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0123] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 23 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0124] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0125] 4) Anodizing: The implant substrate is immersed in an electrolyte (1.3wt% sodium dihydrogen phosphate, 0.12wt% NH4HF2, balance water) and anodized using a pulse power supply, while being ultrasonically treated (frequency 30HZ) to obtain an implant substrate with thoroughly removed sand particles and a porous titanium dioxide film formed on the surface and porous structure.

[0126] The anodizing process is as follows:

[0127] First reverse current: reverse duty cycle 23%, frequency 100HZ, voltage 65V, time 8min, 27℃;

[0128] First forward current: forward duty cycle 23%, frequency 100HZ, voltage 65V, time 2s, 27℃;

[0129] Second reverse current: reverse duty cycle 23%, frequency 100HZ, voltage 125V, time 5min, 27℃;

[0130] Second forward current: forward duty cycle 100%, frequency 10000HZ, voltage 105V, time 80min, 27℃.

[0131] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0132] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 200 mL of potassium dihydrogen phosphate solution (concentration 0.036 mol / L, pH=8.5) at 25℃, and slowly add 40 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃. Let it stand to obtain an implant substrate with calcium and phosphorus deposited on a porous titanium dioxide film of 20-100 nm.

[0133] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0134] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60°C for 5 hours to react and convert titanium dioxide into sodium titanate, resulting in an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure.

[0135] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0136] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0137] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0138] B) Heat to 360℃ in 3 minutes;

[0139] C) Heat to 600℃ in 3 minutes;

[0140] D) Hold at 600℃ for 60 minutes;

[0141] E) Allow to cool naturally to 100°C;

[0142] After heat treatment, an implant matrix with a porous hydroxyapatite film formed on the surface and porous structure is obtained, which is a surface porous superhydrophilic implant without sand particles.

[0143] Example 3

[0144] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0145] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 28 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0146] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0147] 4) Anodizing: The implant substrate is immersed in an electrolyte (1.7wt% sodium dihydrogen phosphate, 0.16wt% NH4HF2, balance water) and anodized using a pulse power supply, while being ultrasonically treated (frequency 30HZ) to obtain an implant substrate with thoroughly removed sand particles and a porous titanium dioxide film formed on the surface and porous structure.

[0148] The anodizing process is as follows:

[0149] First reverse current: reverse duty cycle 25%, frequency 100HZ, voltage 75V, time 7min, 28℃;

[0150] First forward current: forward duty cycle 25%, frequency 100HZ, voltage 75V, time 3s, 28℃;

[0151] Second reverse current: reverse duty cycle 25%, frequency 100HZ, voltage 128V, time 5min, 28℃;

[0152] Second forward current: forward duty cycle 100%, frequency 10000HZ, voltage 110V, time 80min, 28℃.

[0153] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0154] 6) Calcium and phosphorus deposition: The implant substrate was immersed in 300 mL of potassium dihydrogen phosphate solution (concentration 0.036 mol / L, pH=8.5) at 25℃, and 60 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃ was slowly added dropwise. After standing, a 20-100 nm porous titanium dioxide membrane with calcium and phosphorus deposited on the implant substrate was obtained.

[0155] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0156] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60°C for 5 hours to react and convert titanium dioxide into sodium titanate, resulting in an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure.

[0157] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0158] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0159] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0160] B) Heat to 360℃ in 3 minutes;

[0161] C) Heat to 600℃ in 3 minutes;

[0162] D) Hold at 600℃ for 60 minutes;

[0163] E) Allow to cool naturally to 100°C;

[0164] After heat treatment, an implant matrix with a porous hydroxyapatite film formed on the surface and porous structure is obtained, which is a surface porous superhydrophilic implant without sand particles.

[0165] Example 4

[0166] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0167] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 30 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0168] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0169] 4) Anodizing: The implant substrate is immersed in an electrolyte (2.0wt% sodium dihydrogen phosphate, 0.2wt% NH4HF2, and the remainder is water) and anodized using a pulse power supply, while being ultrasonically treated (frequency 30HZ) to obtain an implant substrate with thoroughly removed sand particles and a porous titanium dioxide film formed on the surface and porous structure surface.

[0170] The anodizing process is as follows:

[0171] First reverse current: reverse duty cycle 30%, frequency 100HZ, voltage 80V, time 5min, 30℃;

[0172] First forward current: forward duty cycle 30%, frequency 100HZ, voltage 80V, time 1s, 30℃;

[0173] Second reverse current: reverse duty cycle 30%, frequency 100HZ, voltage 130V, time 6min, 30℃;

[0174] Second forward current: forward duty cycle 100%, frequency 10000HZ, voltage 120V, time 60min, 30℃.

[0175] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0176] 6) Calcium and phosphorus deposition: The implant substrate was immersed in 400 mL of potassium dihydrogen phosphate solution (concentration 0.036 mol / L, pH=8.5) at 25℃, and 80 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃ was slowly added dropwise. After standing, an implant substrate with calcium and phosphorus deposited on a porous titanium dioxide film of 20-100 nm was obtained.

[0177] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0178] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60°C for 5 hours to react and convert titanium dioxide into sodium titanate, resulting in an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure.

[0179] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0180] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0181] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0182] B) Heat to 360℃ in 3 minutes;

[0183] C) Heat to 600℃ in 3 minutes;

[0184] D) Hold at 600℃ for 60 minutes;

[0185] E) Allow to cool naturally to 100°C;

[0186] After heat treatment, an implant matrix with a porous hydroxyapatite film formed on the surface and porous structure is obtained, which is a surface porous superhydrophilic implant without sand particles.

[0187] Comparative Example 1 (using "ultrasonic cleaning + acid etching" process)

[0188] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0189] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0190] 3) Ultrasonic cleaning: The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, and it is first treated at a frequency of 30 Hz for 30 min, and then treated at 60 Hz for 30 min.

[0191] 4) Acid etching: For 1L of pickling solution, use 1 part 50% hydrochloric acid + 1 part 60% sulfuric acid + 1.5 parts water, the etching time is 40min, and the temperature is 85℃.

[0192] 5) Cleaning: Wash with purified water for 5 minutes, rinse for 10 seconds, and spray for 10 seconds.

[0193] 6) Ultrasonic cleaning and drying: First, temperature 60℃, frequency 30HZ, time 20min; then temperature 60℃, frequency 30HZ, time 20min; finally, vacuum drying: temperature 100℃, 40min, to obtain the implant.

[0194] Comparative Example 2 (using "ultrasonic cleaning + acid etching" process)

[0195] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0196] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0197] 3) Ultrasonic cleaning: The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, and it is first treated at a frequency of 30 Hz for 30 min, and then treated at 60 Hz for 30 min.

[0198] 4) Acid etching: For 1L of pickling solution, use 2 parts 50% hydrochloric acid + 1 part 80% nitric acid + 0.05 parts hydrofluoric acid + 1 part water. The acid etching time is 40min and the temperature is 65℃.

[0199] 5) Cleaning: Wash with purified water for 5 minutes, rinse for 10 seconds, and spray for 10 seconds.

[0200] 6) Ultrasonic cleaning and drying: First, temperature 60℃, frequency 30HZ, time 20min; then temperature 60℃, frequency 30HZ, time 20min; finally, vacuum drying: temperature 100℃, 40min, to obtain the implant.

[0201] Comparative Example 3 (the difference from Example 1 is that alternating positive and negative currents were not used in the anodizing process)

[0202] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0203] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0204] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0205] 4) Anodizing: The implant substrate is immersed in an electrolyte (1wt% sodium dihydrogen phosphate, 0.08wt% NH4HF2, balance water) for anodizing, while being treated with ultrasound (frequency 30HZ); the anodizing process is as follows: voltage 100V, time 90min, 25℃.

[0206] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0207] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 100 mL of potassium dihydrogen phosphate solution (concentration 0.035 mol / L, pH=8.0) at 25℃, and slowly add 20 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃, and let it stand.

[0208] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0209] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60℃ for 5 hours to react and convert titanium dioxide into sodium titanate.

[0210] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0211] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0212] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0213] B) Heat to 360℃ in 3 minutes;

[0214] C) Heat to 600℃ in 3 minutes;

[0215] D) Hold at 600℃ for 60 minutes;

[0216] E) Allow to cool naturally to 100°C;

[0217] The implant is obtained after heat treatment.

[0218] Comparative Example 4 (The difference from Example 1 lies in the different process parameters for forward and reverse current anodizing)

[0219] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0220] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0221] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0222] 4) Anodizing: The implant substrate is immersed in an electrolyte (1wt% sodium dihydrogen phosphate, 0.08wt% NH4HF2, balance water) and anodized using a pulse power supply, while being treated with ultrasound (frequency 30HZ).

[0223] The anodizing process is as follows:

[0224] First reverse current: reverse duty cycle 30%, frequency 100HZ, voltage 70V, time 12min, 25℃;

[0225] First forward current: forward duty cycle 30%, frequency 100HZ, voltage 120V, time 3min, 25℃;

[0226] Second reverse current: reverse duty cycle 30%, frequency 100HZ, voltage 120V, time 6min, 25℃;

[0227] Second forward current: forward duty cycle 30%, frequency 100Hz, voltage 160V, time 90min, 25℃.

[0228] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0229] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 100 mL of potassium dihydrogen phosphate solution (concentration 0.035 mol / L, pH=8.0) at 25℃, slowly add 20 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃, and let stand.

[0230] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0231] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60℃ for 5 hours to react and convert titanium dioxide into sodium titanate.

[0232] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0233] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0234] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0235] B) Heat to 360℃ in 3 minutes;

[0236] C) Heat to 600℃ in 3 minutes;

[0237] D) Hold at 600℃ for 60 minutes;

[0238] E) Allow to cool naturally to 100°C;

[0239] The implant is obtained after heat treatment.

[0240] Comparative Example 5 (The difference from Example 1 lies in the different process parameters for anodizing using forward and reverse currents)

[0241] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0242] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0243] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0244] 4) Anodizing: The implant substrate is immersed in an electrolyte (1wt% sodium dihydrogen phosphate, 0.08wt% NH4HF2, the remainder being water) and anodized using a pulse power supply, while simultaneously undergoing ultrasonic treatment (frequency 30HZ).

[0245] The anodizing process is as follows:

[0246] First reverse current: reverse duty cycle 10%, frequency 500HZ, voltage 40V, time 3min, 25℃;

[0247] First forward current: forward duty cycle 10%, frequency 500HZ, voltage 40V, time 3min, 25℃;

[0248] Second reverse current: reverse duty cycle 10%, frequency 500HZ, voltage 50V, time 6min, 25℃;

[0249] Second forward current: forward duty cycle 10%, frequency 500Hz, voltage 50V, time 90min, 25℃.

[0250] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0251] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 100 mL of potassium dihydrogen phosphate solution (concentration 0.035 mol / L, pH=8.0) at 25℃, slowly add 20 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃, and let stand.

[0252] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; vacuum dry at 30℃ for 60 minutes.

[0253] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60℃ for 5 hours to react and convert titanium dioxide into sodium titanate.

[0254] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; vacuum dry at 100℃ for 40 minutes.

[0255] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0256] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0257] B) Heat to 360℃ in 3 minutes;

[0258] C) Heat to 600℃ in 3 minutes;

[0259] D) Hold at 600℃ for 60 minutes;

[0260] E) Allow to cool naturally to 100°C;

[0261] The implant is obtained after heat treatment.

[0262] Comparative Example 6 (the difference from Example 1 is that it uses air drying)

[0263] 1) Degreasing: The machined pure titanium implant substrate is immersed in anhydrous ethanol for 5 minutes, and then subjected to ultrasonic treatment. The proportion of MICR-90 is 0.5 vol%, the temperature is 75℃, the frequency is 30HZ, and the time is 10 minutes.

[0264] 2) Sandblasting: The implant substrate is sandblasted with 80-mesh alumina sand particles at a pressure of 0.5 MPa, a distance of 10 cm, and a time of 20 s to obtain an implant substrate with a porous structure of 10-30 μm on the surface.

[0265] 3) Cleaning: Soak the implant substrate in water for 5 minutes, then rinse for 10 seconds.

[0266] 4) Anodizing: The implant substrate is immersed in an electrolyte (1wt% sodium dihydrogen phosphate, 0.08wt% NH4HF2, balance water) and anodized using a pulse power supply, while being treated with ultrasound (frequency 30HZ).

[0267] The anodizing process is as follows:

[0268] First reverse current: reverse duty cycle 20%, frequency 100HZ, voltage 60V, time 10min, 25℃;

[0269] First forward current: forward duty cycle 20%, frequency 100HZ, voltage 60V, time 3s, 25℃;

[0270] Second reverse current: reverse duty cycle 20%, frequency 100HZ, voltage 120V, time 6min, 25℃;

[0271] Second forward current: forward duty cycle 100%, frequency 10000HZ, voltage 100V, time 90min, 25℃.

[0272] 5) Cleaning: Soak the implant substrate in water for 3 minutes, rinse for 5 minutes, and finally spray for 5 minutes.

[0273] 6) Calcium and phosphorus deposition: Immerse the implant substrate in 100 mL of potassium dihydrogen phosphate solution (concentration 0.035 mol / L, pH=8.0) at 25℃, slowly add 20 mL of calcium nitrate solution (concentration 0.3 mol / L) at 25℃, and let stand.

[0274] 7) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, and rinse 3 times; dry in air at 30°C for 60 minutes.

[0275] 8) Alkaline treatment: The implant matrix is ​​placed in a 5 mol / L sodium hydroxide solution at 60℃ for 5 hours to react and convert titanium dioxide into sodium titanate.

[0276] 9) Cleaning and drying: Soak the implant substrate in water for 3 minutes, then rinse for 5 minutes, rinse 3 times, and finally clean it with ultrasound for 20 minutes at 70℃ and 30HZ; dry it in a 100℃ oven (under air conditions) for 40 minutes.

[0277] 10) Heat treatment: The implant matrix undergoes heat treatment, specifically including:

[0278] A) The temperature was raised from room temperature to 120°C in 30 minutes;

[0279] B) Heat to 360℃ in 3 minutes;

[0280] C) Heat to 600℃ in 3 minutes;

[0281] D) Hold at 600℃ for 60 minutes;

[0282] E) Allow to cool naturally to 100°C;

[0283] The implant is obtained after heat treatment.

[0284] Performance testing

[0285] (a) Scanning electron microscopy test:

[0286] Example 1: SEM images of implants at different stages of surface treatment. Figure 1-3 As shown. Wherein: Figure 1 The image shows an SEM image of the surface of the implant substrate after sandblasting in Example 1. It can be seen that a uniformly distributed micron-pore structure was formed on the surface after sandblasting. Figure 2The image shows a SEM image of the surface of the implant substrate obtained after anodizing in Example 1. It can be seen that a uniformly distributed nanoporous titanium dioxide film was formed on the surface after anodizing. Figure 3 The image shows the surface SEM image of the implant obtained in Example 1. It can be seen that the implant surface presents a fibrous, rough micro-nano structure.

[0287] Figure 4 This is a SEM image of the surface of the implant obtained in Example 4. Similar to Example 1, the implant surface can be observed to exhibit a fibrous, rough micro / nano structure.

[0288] Figure 5 and Figure 6 The images show SEM images of the surfaces of the implants obtained in Comparative Examples 1 and 2, respectively. The images reveal that sand particles remaining after sandblasting are still present in the implants, indicating that the traditional "ultrasound + acid etching" method cannot completely remove the residual sand particles.

[0289] Figure 7 The image shows a SEM image of the surface of the implant obtained in Comparative Example 4. The image reveals that very few smaller depressions are formed within the rough concave surface of the implant, and the pores merge, resulting in a small number of pores. This indicates an inability to form a sufficient micro / nano surface, which is attributed to improper control of the anodizing process parameters.

[0290] Figure 8 The image shows a SEM image of the surface of the implant obtained in Comparative Example 5. The image reveals that the concave surfaces of the implant are still preserved, with a few small pores in some areas. However, the entire implant surface does not form a network of interconnected pores, which is attributed to improper control of the anodizing process parameters.

[0291] (ii) Elemental analysis test:

[0292] Figure 9 and Figure 10 The images show the EDS analysis spectra of the implants after anodizing in Example 1 and the final implants. As can be seen from the images, there are almost no sand particles (Al elements) remaining in the implants.

[0293] Figure 11-13 The images show the EDS analysis spectra of the implants obtained in Comparative Examples 1-3, respectively. As can be seen from the images, there is a relatively large amount of residual Al element in the implants.

[0294] (III) Surface hydrophilicity test:

[0295] Figure 14-17The results of surface hydrophilicity tests on the implants obtained in Example 1, Comparative Examples 1-2, and Comparative Example 6 are shown in the figure. As can be seen from the figure, the implant obtained in Example 1 has strong hydrophilicity (contact angle 7.13°), while the implants in Comparative Examples 1-2 and Comparative Example 6 have relatively weak hydrophilicity (contact angles of 17.15°, 28.10°, and 35.30°, respectively).

[0296] Unless otherwise specified, the raw materials and equipment used in this invention are all commonly used in the field; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0297] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing a porous, superhydrophilic implant with no sand residue, characterized in that... include: First, the implant substrate is degreased, and then sandblasted to form a 10-30μm porous structure on the surface. After cleaning, the implant substrate is immersed in an electrolyte for anodizing and ultrasonic treatment at the same time, so as to completely remove sand particles and form a porous titanium dioxide film on the surface and porous structure of the implant substrate. The anodizing conditions are as follows: First reverse current: reverse duty cycle 20-30%, frequency 90-110Hz, voltage 60-80V, time 5-10min, temperature 25-30℃; First forward current: forward duty cycle 20-30%, frequency 90-110 Hz, voltage 60-80V, time 1-3s, temperature 25-30℃; Second reverse current: reverse duty cycle 20-30%, frequency 90-110 Hz, voltage 120-130V, time 3-6min, temperature 25-30℃; Second forward current: forward duty cycle 20-100%, frequency 3000-10000 Hz, voltage 100-120V, time 60-90min, temperature 25-30℃. After cleaning, the implant substrate is immersed in an alkaline soluble phosphate solution at 20-30℃, and a soluble calcium salt solution at 20-30℃ is added dropwise. After standing, an implant substrate with calcium and phosphate deposited on a porous titanium dioxide film of 20-100nm is obtained. After washing with water and vacuum drying, the implant matrix is ​​placed in sodium hydroxide solution for static reaction to obtain an implant matrix with a calcium-phosphorus-doped porous sodium titanate adhesive layer on the surface and porous structure. Water washing, vacuum drying, and heat treatment are performed to obtain an implant matrix with a porous hydroxyapatite membrane formed on its surface and porous structure.

2. The preparation method according to claim 1, characterized in that: The implant matrix is ​​made of pure titanium.

3. The preparation method according to claim 1, characterized in that: The electrolyte comprises: 1-2 wt% sodium dihydrogen phosphate, 0.08-0.2 wt% NH4HF2, and the balance being water; the frequency of the ultrasonic treatment is 25-35 Hz.

4. The preparation method according to claim 1, characterized in that: The degreasing process specifically includes: immersing the machined implant substrate in anhydrous ethanol for 3-7 minutes, followed by ultrasonic treatment. The degreasing agent concentration is 0.3-0.7 vol%, the temperature is 70-80℃, the frequency is 25-35 Hz, and the time is 5-10 minutes.

5. The preparation method according to claim 1, characterized in that: The sandblasting specifically includes: sandblasting the implant substrate with alumina sand particles, with a sandblasting pressure of 0.5-0.6MPa, a sandblasting distance of 8-12cm, and a time of 20-30s.

6. The preparation method according to claim 1, characterized in that: The concentration of the soluble phosphate solution is 0.03-0.04 mol / L, and the pH is 7.5-8.5; The concentration of the soluble calcium salt solution is 0.25-0.35 mol / L; After the addition is complete, the molar ratio of calcium to phosphorus is 1.6-1.7:1; The soluble phosphate is selected from potassium dihydrogen phosphate, sodium dihydrogen phosphate dihydrate, and ammonium dihydrogen phosphate; The soluble calcium salt is selected from calcium nitrate tetrahydrate, calcium chloride, calcium lactate, calcium acetate monohydrate, and calcium gluconate monohydrate.

7. The preparation method according to claim 1, characterized in that: The sodium hydroxide solution was prepared at a temperature of 50-60℃, a concentration of 4-6 mol / L, and a standing time of 4-6 h.

8. The preparation method according to claim 1, characterized in that: The heat treatment specifically includes: A) The temperature rises from room temperature to 120°C in 25-35 minutes; B) Heat to 360℃ in 25-35 minutes; C) Heat to 600℃, taking 25-35 minutes; D) Hold at 600℃ for 50-70 minutes; E) Allow to cool naturally to 100°C.

9. A porous, superhydrophilic implant with no sand residue obtained by the preparation method according to any one of claims 1-8, characterized in that: It includes an implant matrix with a porous surface structure and a porous hydroxyapatite membrane formed on the surface of the implant matrix and the porous surface structure.

Images