Implant surface treatment technology

Abstract

The present invention relates to the field of bone implant technology, and in particular to a novel implant surface treatment technology, the method comprising the following steps: selecting hydroxyapatite powder, uniformly mixing deionized water and hydroxyapatite powder to prepare a hydroxyapatite suspension with a concentration of 8 mg / ml; sealing the screw opening on the upper part of the implant, immersing the implant in the suspension for 1 minute, and then transferring it to a dryer and drying it at 60°C for 2 minutes. The present invention has the advantages of being able to perform femtosecond laser combined with hydroxyapatite suspension evaporation solvent crystallization on the surface of the implant to improve the soft tissue sealing and bone bonding ability around the implant, and improve the implant repair and aesthetic effect. By proposing a femtosecond laser combined with hydroxyapatite suspension evaporation solvent crystallization method to treat the implant surface, while constructing the micro-nano morphology of the implant surface, a calcium-phosphorus coating is melted to improve the biological activity of the implant surface, without contacting the implant surface, and the treatment process is pollution-free.

Description

Technical Field

[0001] The present invention relates to the technical field of bone implants, in particular to a novel implant surface treatment technology. Background Art

[0002] The long-term and stable biological function of implants depends not only on good bone integration but also on good peri-implant soft tissue closure.

[0003] The bioinertness of implant materials limits their ability to directly integrate with bone tissue and can lead to serious complications. Recent studies have demonstrated that specific micro- and nano-topography of implant surfaces can enhance roughness and hydrophilicity, facilitating the adhesion and proliferation of BMSCs and promoting their osteogenic differentiation, thereby promoting osseointegration at the implant-body interface. Furthermore, hydroxyapatite coatings, which contain mineral compositions similar to those of bone tissue and exhibit excellent bioactivity, can enhance the osteogenic capacity of BMSCs.

[0004] Furthermore, the surface topography of the implant neck is a key factor influencing the adhesion and differentiation of fibroblasts on the implant surface. Existing implant necks are mostly smooth, resulting in weak attachment of fibroblasts and collagen fibers, which are arranged parallel to the implant or in a circular pattern around the implant. This results in a soft tissue seal that is far less effective than that of natural teeth, making them more susceptible to mechanical and toxic irritation, and potentially leading to peri-implantitis.

[0005] This technology utilizes a femtosecond laser combined with hydroxyapatite suspension evaporation and solvent crystallization to treat implants. By constructing a multi-level micro- / nanoscale composite microgroove structure, collagen fibers at the implant neck can vertically penetrate the implant surface, forming a soft tissue seal similar to that of a natural tooth. Simultaneously, the surface microgrooves and hydroxyapatite coating promote the adhesion, proliferation, and osteogenic differentiation of bone marrow mesenchymal stem cells, effectively improving the implant's osseointegration.

[0006] Surface modification is the basis for the long-term and effective function of implants. Traditional implant surface treatment technology has the following shortcomings:

[0007] 1. Sandblasting technology: ① Due to the size differences of abrasive particles and the instability of actual operation, there are often problems of uneven roughness and irregular microstructure, which are not conducive to the combination of implants and bone tissue; ② During the sandblasting process, fine sand particles may be embedded into the implant surface, causing implant contamination and further affecting its application effect in the organism.

[0008] 2. Acid etching technology: ① The acid etching process is difficult to control precisely, has poor repeatability, and easily forms a surface with uneven roughness; ② It is difficult to form an ideal surface microstructure, which limits the improvement of biological activity; ③ Improper treatment can easily cause surface corrosion, affecting the long-term stability of the implant; ④ The residual acid etching solution on the surface causes changes in the surface chemical composition, which greatly affects its biocompatibility.

[0009] 3. Anodizing technology: ① The processing efficiency is low, complex and time-consuming, and the resulting surface microstructure is single, which is not conducive to cell adhesion and proliferation; ② The thickness of the formed oxide layer is difficult to control. Too thick will increase the brittleness of the implant, and too thin will not have good bone induction; ③ It is not suitable for certain specific implant materials.

[0010] 4. Chemical coating technology: ① The bonding strength with the implant matrix is ​​insufficient, and the coating may peel off during long-term use, causing implant failure; ② The coating material has biocompatibility issues.

[0011] 5. Plasma spraying: The bonding strength between the coating and the substrate is relatively low, and microcracks may exist inside the coating, affecting the long-term stability of the implant.

[0012] To this end, we proposed a new implant surface treatment technology to solve this problem. Summary of the Invention

[0013] The purpose of the present invention is to provide a new implant surface treatment technology, which has the advantages of being able to perform femtosecond laser combined with hydroxyapatite suspension evaporation solvent crystallization treatment on the implant surface to improve the soft tissue sealing and bone integration ability around the implant, improve the implant restoration and aesthetic effect, and solve the problems raised in the above-mentioned background technology.

[0014] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a new implant surface treatment technology, the method comprising the following steps:

[0015] S1: Prepare hydroxyapatite powder by mixing deionized water and hydroxyapatite powder to prepare a hydroxyapatite suspension with a concentration of 8 mg / ml;

[0016] S2: After sealing the screw hole on the implant, immerse the implant in the suspension for 1 minute, then transfer it to a dryer and dry it at 60°C for 2 minutes;

[0017] S3: Repeat the above step S2 three times to form a uniform calcium-phosphorus coating with a thickness of about 200 to 500 nm on the surface of the implant;

[0018] S4: Femtosecond laser processing: The processing device consists of a femtosecond laser system, a three-axis mobile platform, and a rotating platform. First, the implant is fixed to the rotating platform, which rotates at a speed of 400 mm / s. At the same time, the three-axis platform moves vertically at a constant speed. AOFEMTO femtosecond laser and corresponding regenerative amplifier are used.

[0019] S5: After adjustment, the output laser parameters are wavelength 1030nm, pulse width 300fs, and repetition frequency 100kHz. By changing the laser incident angle, the femtosecond laser is vertically irradiated to the implant surface.

[0020] S6: The laser is processed at a speed of 400 mm / s, using different numbers of laser beams in parallel to construct micro-groove surface morphologies of different sizes.

[0021] Preferably, in step S1, a ball milling method is used to prepare nano-hydroxyapatite powder with a particle size of 50 to 100 nm and a Ca / P ratio of 1.67.

[0022] Preferably, in step S1, 0.5 wt% polyacrylic acid dispersant is added when preparing the suspension, the magnetic stirring time is 4 hours, the rotation speed is controlled at 800 rpm, and ultrasonic treatment is performed after stirring, the ultrasonic parameters are controlled at 40 kHz, and the ultrasonic time is 30 minutes.

[0023] Preferably, in step S2, gradient drying is set during drying, firstly baking at 60°C for 2 minutes, then curing by infrared radiation, and finally vacuum annealing at 200°C for 2 hours.

[0024] Preferably, in step S3, when the implant is cyclically cured, weight gain is monitored online by a quartz crystal microbalance to achieve three cycles.

[0025] Preferably, in step S3, after the calcium phosphate coating is formed, the morphology is detected by field emission scanning electron microscopy, the surface chemical composition is analyzed by X-ray photoelectron spectroscopy, and the bonding strength is evaluated by nanoindentation testing.

[0026] Preferably, in step S4, the repeatability of the three-axis mobile platform is ±0.5 μm, the radial runout of the air-bearing turntable is less than 1 μm, and the speed adjustment range is 0 to 1000 rpm.

[0027] Preferably, in step S5, the laser beam adopts a spatial light modulator to realize a top-hat flat-top beam, the laser adopts a spiral scanning mode, and the pitch adjustment range is 10 to 100 μm.

[0028] Preferably, in step S6, argon protection is used for environmental control during laser processing, the O2 concentration is less than 50 ppm, and real-time plasma monitoring is performed.

[0029] Preferably, in step S6, a femtosecond laser is used to form a hole-shaped micro-nano composite structure on the surface of the implant, and the specific data range is:

[0030] Primary roughness structure: groove diameter 10-50 μm, hole depth 4-10 μm;

[0031] Secondary roughness structure: pore diameter: 1-2 μm;

[0032] Tertiary roughness structure: pore diameter: 70-100nm.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention has the advantage of being able to perform femtosecond laser combined with hydroxyapatite suspension evaporation solvent crystallization treatment on the surface of the implant to improve the soft tissue sealing and bone bonding ability around the implant, and improve the implant restoration and aesthetic effect. By proposing a femtosecond laser combined with hydroxyapatite suspension evaporation solvent crystallization method to treat the implant surface, while constructing the micro-nano morphology of the implant surface, a calcium-phosphorus coating is melted to improve the biological activity of the implant surface. This method is accurate and controllable, does not contact the implant surface, and the treatment process is pollution-free. By using this technology to construct a micron-nano multi-level composite structure on the implant surface, not only can the collagen fibers at the implant neck be vertically inserted into the implant surface to form a soft tissue seal similar to natural teeth, but it also promotes the adhesion, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells on the implant surface, thereby enhancing the bone bonding between the implant and the body.

[0035] 2. The present invention utilizes a femtosecond laser in combination with a hydroxyapatite suspension evaporation solvent crystallization method to treat implants. First, a hydroxyapatite suspension is prepared, which is then evenly sprayed on the implant surface. After drying, a hydroxyapatite coating is prepared. A laser oscillator is then used to generate ultrashort pulses in the femtosecond range, which are then transmitted through the air to a focusing device to focus the light beam, and the light beam is precisely targeted and focused onto an ultrafine spatial region at the micron level. The sample is fixed on a motorized displacement and rotation platform with three-axis motion for processing. The pulse impacts the sample surface vertically, causing local ablation. By adjusting parameters such as pulse power, scanning speed, frequency, and pulse duration, surface micromorphologies with specific shapes, sizes, and spatial arrangements, such as holes, grooves, and coral island-like structures, can be quickly and accurately constructed and prepared. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the implant groove of the present invention. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] A novel implant surface treatment technology comprises the following steps:

[0039] S1: Prepare hydroxyapatite powder by mixing deionized water and hydroxyapatite powder to prepare a hydroxyapatite suspension with a concentration of 8 mg / ml;

[0040] In this embodiment, in the above step S1, a ball milling method is used to prepare nano-hydroxyapatite powder with a particle size of 50 to 100 nm and a Ca / P ratio of 1.67.

[0041] Preferably, in the above step S1, 0.5 wt% polyacrylic acid dispersant is added when preparing the suspension, the magnetic stirring time is 4 h, the speed is controlled at 800 rpm, and ultrasonic treatment is performed after stirring, the ultrasonic parameters are controlled at 40 kHz, and the ultrasonic time is 30 min.

[0042] S2: After sealing the screw hole on the implant, immerse the implant in the suspension for 1 minute, then transfer it to a dryer and dry it at 60°C for 2 minutes;

[0043] In this embodiment, in the above step S2, gradient drying is set during drying, firstly, initial baking is performed at 60°C for 2 minutes, then infrared radiation curing is adopted, and finally vacuum annealing is performed at 200°C for 2 hours.

[0044] S3: Repeat the above step S2 three times to form a uniform calcium-phosphorus coating with a thickness of about 200 to 500 nm on the surface of the implant;

[0045] In this embodiment, in the above step S3, when the implant is cyclically cured, the weight gain is monitored online by a quartz crystal microbalance, and three cycles are achieved.

[0046] In this embodiment, in the above step S3, after the calcium phosphate coating is formed, the morphology is detected by field emission scanning electron microscopy, the surface chemical composition is analyzed by X-ray photoelectron spectroscopy, and the bonding strength is evaluated by nanoindentation testing.

[0047] S4: Femtosecond laser processing: The processing device consists of a femtosecond laser system, a three-axis mobile platform, and a rotating platform. First, the implant is fixed to the rotating platform, which rotates at a speed of 400 mm / s. At the same time, the three-axis platform moves vertically at a constant speed. AOFEMTO femtosecond laser and corresponding regenerative amplifier are used.

[0048] In this embodiment, in the above step S4, the repeatability of the three-axis mobile platform is ±0.5 μm, the radial runout of the air-bearing turntable is less than 1 μm, and the speed adjustment range is 0 to 1000 rpm.

[0049] S5: After adjustment, the output laser parameters are wavelength 1030nm, pulse width 300fs, and repetition frequency 100kHz. By changing the laser incident angle, the femtosecond laser is vertically irradiated to the implant surface.

[0050] In this embodiment, in the above step S5, the laser beam adopts a spatial light modulator to realize a top-hat flat-top beam, the laser adopts a spiral scanning mode, and the pitch adjustment range is 10 to 100 μm.

[0051] S6: The laser is processed at a speed of 400 mm / s, using different numbers of laser beams in parallel to construct micro-groove surface morphologies of different sizes.

[0052] In this embodiment, in the above step S6, the environment control during laser processing adopts argon protection, the O2 concentration is less than 50ppm, and real-time plasma monitoring is performed.

[0053] In this embodiment, in the above step S6, a femtosecond laser is used to form a hole-shaped micro-nano composite structure on the surface of the implant, and the specific data range is:

[0054] Primary roughness structure: groove diameter 10-50 μm, hole depth 4-10 μm;

[0055] Secondary roughness structure: pore diameter: 1-2 μm;

[0056] Tertiary roughness structure: pore diameter: 70-100nm.

[0057] In summary, the present invention uses a femtosecond laser combined with a hydroxyapatite suspension evaporation solvent crystallization method to treat implants. First, a hydroxyapatite suspension is prepared, and then evenly sprayed on the implant surface. After drying, a hydroxyapatite coating is prepared. Then, a laser oscillator generates ultrashort pulses of the femtosecond order, which are transmitted through the air to a focusing device to focus the light beam, and the light beam is precisely targeted and focused to an ultrafine space area at the micron level. The sample is fixed on a motorized displacement and rotation platform with three-axis motion for processing. The pulse impacts the sample surface vertically, causing local ablation. By adjusting parameters such as pulse power, scanning speed, frequency, and pulse duration, surface micromorphologies with specific shapes, sizes, and spatial arrangements, such as holes, grooves, and coral island-like structures, can be quickly and accurately constructed and prepared.

[0058] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0059] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A new implant surface treatment technology, characterized by: The steps include: S1: Prepare hydroxyapatite powder by mixing deionized water and hydroxyapatite powder to prepare a hydroxyapatite suspension with a concentration of 8 mg / ml; S2: After sealing the screw hole on the implant, immerse the implant in the suspension for 1 minute, then transfer it to a dryer and dry it at 60°C for 2 minutes; S3: Repeat the above step S2 three times to form a uniform calcium-phosphorus coating with a thickness of 200 to 500 nm on the surface of the implant; S4: Femtosecond laser processing: The processing device consists of a femtosecond laser system, a three-axis mobile platform, and a rotating platform. First, the implant is fixed to the rotating platform, which rotates at a speed of 400 mm / s. At the same time, the three-axis platform moves vertically at a constant speed. AOFEMTO femtosecond laser and corresponding regenerative amplifier are used. S5: After adjustment, the output laser parameters are wavelength 1030nm, pulse width 300fs, and repetition frequency 100kHz. By changing the laser incident angle, the femtosecond laser is vertically irradiated to the implant surface. S6: The laser is processed at a speed of 400 mm / s, using different numbers of laser beams in parallel to construct micro-groove surface morphologies of different sizes.

2. The novel implant surface treatment technology according to claim 1, characterized in that: In the step S1, a ball milling method is used to prepare nano-hydroxyapatite powder with a particle size of 50 to 100 nm and a Ca / P ratio of 1.

67.

3. The novel implant surface treatment technology according to claim 1, characterized in that: In the step S1, 0.5 wt% of polyacrylic acid dispersant was added when preparing the suspension, the magnetic stirring time was 4 h, the rotation speed was controlled at 800 rpm, and ultrasonic treatment was performed after stirring, the ultrasonic parameters were controlled at 40 kHz, and the ultrasonic time was 30 min.

4. The novel implant surface treatment technology according to claim 1, characterized in that: In step S2, gradient drying is set during drying, firstly, initial baking is performed at 60°C for 2 minutes, then infrared radiation curing is adopted, and finally vacuum annealing is performed at 200°C for 2 hours.

5. The novel implant surface treatment technology according to claim 1, characterized in that: In step S3, when the implant is cyclically cured, the weight gain is monitored online by a quartz crystal microbalance, and three cycles are performed.

6. The novel implant surface treatment technology according to claim 1, characterized in that: In step S3, after the calcium phosphate coating is formed, the morphology is detected by field emission scanning electron microscopy, the surface chemical composition is analyzed by X-ray photoelectron spectroscopy, and the bonding strength is evaluated by nanoindentation testing.

7. The novel implant surface treatment technology according to claim 1, characterized in that: In step S4, the repeatability of the three-axis mobile platform is ±0.5 μm, the radial runout of the air-bearing turntable is less than 1 μm, and the speed adjustment range is 0 to 1000 rpm.

8. The novel implant surface treatment technology according to claim 1, characterized in that: In step S5, the laser beam adopts a spatial light modulator to realize a top-hat flat-top beam, the laser adopts a spiral scanning mode, and the pitch adjustment range is 10 to 100 μm.

9. The novel implant surface treatment technology according to claim 1, characterized in that: In step S6, during laser processing, the environment is controlled by argon protection, the O2 concentration is less than 50 ppm, and the plasma is monitored in real time.

10. The novel implant surface treatment technology according to claim 1, characterized in that: In step S6, a femtosecond laser is used to form a hole-shaped micro-nano composite structure on the surface of the implant, and the specific data range is: Primary roughness structure: groove diameter 10-50 μm, hole depth 4-10 μm; Secondary roughness structure: pore diameter: 1-2 μm; Tertiary roughness structure: pore diameter: 70-100nm.

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