CN104523341B - The manufacture method of the immediate implantation teeth with periodontal bioactivity - Google Patents

Abstract

The invention relates to a manufacturing method of an immediate dental implant with periodontal bioactivity, comprising the following steps: (1) preparing a pure titanium or titanium alloy implant core; (2) preparing a self-curing calcium magnesium phosphate powder; (3) preparing a collagen solution (4) Preparation of artificially synthesized substance P polypeptide; (5) Preparation of SP cross-linked collagen matrix; (6) Calcium magnesium phosphate powder mixed with SP cross-linked collagen matrix to prepare bioactive paste; (7) Bioactive paste Coating the root of the implant core, pressurizing, solidifying and freeze-drying to make an artificial tooth root with periodontal bioactivity; (8) connecting the crown of the implant core to an artificial crown suitable for the shape of the missing tooth to make an immediate implant. This method constructs an artificial tooth root with a bionic cementum structure, so that the prepared dental implant has part of the life characteristics of a natural implanted tooth, has the biological activity of autonomous periodontal healing, and can be implanted immediately after tooth extraction, which significantly shortens the restoration time of missing teeth and improves the quality of life. planting success rate.

Description

Method for manufacturing immediate dental implants with periodontal bioactivity

technical field

The invention belongs to the technical field of dental artificial implants, and relates to a method for manufacturing biologically active dental implants, in particular to a method that can be implanted immediately after tooth extraction and actively induces the formation of osseointegration between the root of the implant and the bone tissue of the alveolar socket dental implant manufacturing method.

Background technique

Dental implant (dental implant) is called the third pair of teeth of human beings and has become a symbolic technology of modern stomatology. The development of modern dental implant technology is based on the theory of osseointegration (or osseointegration) proposed by Branemark, the father of implant in the 1960s. The American Academy of Dental Implantology defines osseointegration as: normal remodeled bone is in direct contact with the implant, soft tissue can be seen under a light-free microscope, and the load of the implant can be continuously conducted and dispersed in the bone tissue.

Modern dental implants are mainly made of inorganic materials such as titanium metal or ceramics through mechanical processing. The surface of the material has good biocompatibility, but it is difficult to build a sustainable and stable regeneration-induced biological activity, so the smooth healing of the implant after implantation Good primary stability is required, that is, the implant can form a sufficient area of direct contact with the surrounding alveolar bone when placed. For this reason, traditional implant surgery is generally scheduled for 3-6 months after tooth extraction when the alveolar bone tissue regeneration and healing are good, and after implantation, embedding or static healing is required for 3 months to obtain good implant osseointegration. A second operation was performed. Connects to the upper denture structure.

Immediate implant is to implant the implant into the alveolar socket at the same time as the tooth is extracted. After it heals, the denture can be connected to repair the missing tooth, thereby reducing the number of operations and surgical trauma, and restoring the occlusal and aesthetic functions of the teeth early. It is the development of oral reconstruction technology. important direction. Recent studies have shown that immediate implantation after tooth extraction can also achieve osseointegrated healing. However, it is difficult to completely match the shape of the fresh alveolar socket with the implant, and the alveolar bone may be damaged due to periodontal and apical diseases, so immediate implantation is often difficult to obtain the necessary Its initial stability and good healing environment, its short-term and long-term functional and aesthetic effects are still controversial. At present, the suitable sites for immediate implantation are generally anterior teeth and premolars, which require at least 3-5mm of bone mass at the root to stably implant the implant, while the alveolar sockets of the molar sites are wide after tooth extraction, and the interalveolar bone mass It is difficult to support the stability of the implant, so immediate implantation is rarely used clinically, and it is generally implanted when the alveolar socket is completely healed 4 months after tooth extraction. If there is a large amount of bone defect and/or soft tissue inflammation at the tooth site due to periodontal disease and/or apical periodontitis, or the patient has systemic diseases such as osteoporosis and diabetes, it is not an indication for immediate implantation. In addition, the alveolar bone wall on the labial and buccal side of the anterior teeth is mainly composed of weak cortical bone, which will undergo physiological resorption after tooth extraction. The existing implants cannot prevent this bone resorption, which may lead to gingival recession and implant failure. The edges are exposed, seriously affecting the aesthetic effect. To sum up, when the current implants are designed for immediate implantation, more stringent selection of indications is required, and generally more complex materials and technical assistance are required, and the clinical application is more limited.

It is an important direction for the development of implant technology and theory to use bioactive factor loading to enable implants to induce bone regeneration and reconstruction, and to improve the feasibility and success rate of immediate implantation. At present, growth factors or hormones related to bone regeneration, such as BMP and parathyroid hormone, are commonly used to construct bioactive modified surfaces on the surface of implants through various physical or chemical methods. However, these growth factors are macromolecular proteins, and there are many problems in obtaining, synthesizing, positioning and transporting, and controlling their activity, especially on the surface of titanium metal implants, how to load organic biomolecules, how to maintain their biological activity stably, and how to To ensure its biological safety, there are still many technical bottlenecks, and there is still a big gap from the actual clinical application conditions of dental implants.

Contents of the invention

The purpose of the present invention is to provide a method for manufacturing immediate dental implants with periodontal bioactivity. The dental implant prepared by this method has an artificial tooth root with a bionic natural tooth root cementum structure, and has the ability to independently induce bone regeneration and reconstruction. Immediate implantation after tooth extraction simulates the periodontal healing process of natural transplanted teeth and solves the problem of early restoration and reconstruction of missing teeth.

In order to achieve the above object, the present invention provides the following technical solution: a method for manufacturing an immediate dental implant with periodontal bioactivity, which includes the following steps: (1) preparing a pure titanium or titanium alloy implant core, wherein the implant Body core comprises crown and root, and screw hole is arranged in described crown, is used for fixing artificial tooth crown, and the outer surface of described root has screw thread, is used for dispersing occlusal stress; (2) prepares self-curing calcium magnesium phosphate powder, The specific method is: according to the molar ratio of Mg:Ca=3:1, Mg(OH) ₂ is mixed with CaCO ₃ , MgHPO ₄ 3H ₂ O is mixed with CaHPO ₄ , and then the two mixtures are mixed according to the molar ratio of 1:2 Mixing, and then sintering the mixed material at 1100 degrees Celsius for 5 hours to prepare the calcium magnesium phosphate material Mg _2.25 Ca _0.75 (PO ₄ ) ₂ ; the obtained calcium phosphate magnesium sintered material Mg _2.25 Ca _0.75 (PO ₄ ) was crushed by a mortar ₂ , and then sieved with a 355 μm aperture sieve, and then ground with a ball mill for 10 minutes to make a powder, and the powder was mixed with Ca(H ₂ PO ₄ ) ₂ ·H ₂ O at a molar ratio of 1:1 Mix and stir for 30 seconds to make self-curing calcium magnesium phosphate powder; (3) prepare collagen solution, the specific method is: adding type I collagen fibers into 5mol/L acetic acid solution according to the mass volume concentration of 3% W/V, Dissolve under magnetic stirring at a temperature of 4°C, and then dialyze the solution with semi-permeable double-distilled water for 48 hours to remove the acetic acid component to make a collagen solution; (4) prepare artificially synthesized substance P polypeptides, the specific method is: use automatic peptide synthesis According to the following amino acid sequence Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 artificially synthesized substance P polypeptide; (5) preparing substance P covalently cross-linked modified collagen matrix, specifically The method is as follows: using 1-ethyl-(3,3′-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide as covalent cross-linking agents, the substance P polypeptide, 1 -Ethyl-(3,3'-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide are mixed according to the molar ratio of 1:1.2:0.6, and then the mixture is 1% according to the mass volume concentration W/V is added in the collagen solution, first magnetically stirred and reacted for 24 hours, then semi-permeable membrane double distilled water dialysis for 72 hours to make P substance covalently cross-linked modified collagen matrix; (6) the self-curing calcium phosphate The citric acid solution of magnesium powder and 0.5mol/L is 3.0g: 1ml according to the mass volume ratio and mixes and mixes to make self-curing calcium magnesium phosphate paste, then with volume ratio 60%: 40% the described self-curing calcium phosphate The magnesium paste is mixed with the covalently cross-linked modified collagen matrix of the P substance to make a bioactive paste; (7) prepare a two-stage bioactive paste pressurized curing mold, the upper section is used to accommodate and fix the The crown (1), the lower section is used to accommodate the root (2) and the bioactive paste, so that the root The surface of (2) is coated with a bioactive paste with a thickness of 3mm, and then the two-stage bioactive paste pressurized solidification mold is put together and pressurized to 200-300kPa, and placed in a 100% humidity environment 24 The calcium magnesium phosphate paste was solidified within 1 hour, then frozen at -80°C for 12 hours, and vacuum freeze-dried for 48 hours, so that the collagen components in the calcium magnesium phosphate crystals were solidified into a three-dimensional fiber network structure, and a bionic natural tooth root was made. The artificial tooth root of cementum structure; (8) prepare the artificial tooth crown (8), make its shape similar to the shape of the missing tooth, and fix it on the crown (1) by screws (7), you can make immediate dental implant .

Further, wherein, the connection between the crown and the root has a step of 0.8-1 mm.

Furthermore, wherein, a bioactive layer with a thickness of 3 mm is finally formed on the outer surface of the root.

The advantage of the present invention is that: the dental implant core is prepared by pure titanium or titanium alloy, which has good biocompatibility, machining performance, and mechanical properties, and can provide the overall strength similar to natural teeth for immediate implants; the crown According to the position of the missing tooth, screws can be used to connect the artificial crown of the corresponding shape, which is suitable for the restoration of missing teeth in different parts; the root part is coated with calcium magnesium phosphate-collagen composite bioactive material, which is based on calcium phosphate, through The thermochemical reaction partially replaces calcium ions with magnesium ions to obtain enhanced mechanical properties and improved bone tissue guidance activity. By modulating and mixing Substance P (SP) to covalently cross-link modified collagen, a sustained and stable peptide mobilization stem cell biology is obtained. Activity, through pressurized self-curing and freeze-drying, the structure and function of the natural tooth root cementum can be simulated, and the bionic artificial tooth root can be made. The dental implant can be implanted immediately after tooth extraction, has the periodontal biological activity of autonomously inducing alveolar bone regeneration and reconstruction, can significantly shorten the restoration time of missing teeth, and improve the success rate.

Description of drawings

Fig. 1 is an enlarged view of an immediate implant with periodontal bioactivity manufactured by the method of the present invention.

detailed description

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, and the content of the specific embodiments is not intended to limit the protection scope of the present invention.

The manufacturing method of the immediate implant with periodontal bioactivity according to the present invention utilizes the non-coating biological modification technology combining material science and tissue engineering technology to construct the artificial tooth root with bionic cementum structure, so that the prepared implant The tooth can be implanted immediately after tooth extraction, which has some life characteristics of natural implanted teeth, greatly shortens the restoration time of missing teeth, and significantly improves the success rate of implantation.

The idea of the present invention is to use small molecule peptides to build biological activity, and use self-curing calcium phosphate materials to build natural cementum biomimetic structures. Small molecule active peptides have significant advantages in synthesis preservation, functional positioning and safety control, and are a better choice for constructing tissue engineering biological activity. Studies have shown that Substance P (Substance P, SP) is widely distributed in bone marrow stromal cells, vascular endothelial cells, neutrophils, epithelial cells, etc., and is highly conserved. It is a neuroendocrine signal to mobilize stem cell activation and differentiation. It has various functions such as inducing angiogenesis, promoting bone regeneration and bone turnover, and is a convenient, easy-to-obtain, diverse, safe and reliable small molecule active peptide. Self-curing calcium phosphate has unique advantages in the construction of composite biomaterials: calcium phosphate itself has bone tissue guiding activity, and can self-cure from a paste state that can be shaped at will to a hydroxyapatite crystal state with good strength. The curing strength can be controlled by ion exchange and other methods, and the curing reaction is mild. Bioactive ingredients can be loaded by physical adsorption, covalent cross-linking and other methods to achieve multiple biological activities of bone conduction + bone induction.

In the present invention, a high-precision lathe is first used to prepare a pure titanium or titanium alloy dental implant core. As shown in FIG. 1 , the pure titanium or titanium alloy implant core includes a crown 1 and a root 2 , and the connection between the crown 1 and the root 2 has a step 3 of 0.8-1 mm. The center of the crown 1 has a threaded hole 4 through which a screw 7 inserted into the threaded hole 4 can fix an artificial dental crown 8 . The outer surface of the root 2 has threads 5 through which the occlusal stress is dispersed.

The second step is to prepare self-curing calcium magnesium phosphate powder. The specific method is: according to the molar ratio of Mg:Ca=3:1, Mg(OH) ₂ is mixed with CaCO ₃ , MgHPO ₄ 3H ₂ O is mixed with CaHPO ₄ , and then the two mixtures are mixed according to the molar ratio of 1:2 mixing, and then sintering the mixed material at 1100 degrees Celsius for 5 hours, replacing part of the calcium ions with magnesium ions through a thermochemical reaction to prepare a calcium magnesium phosphate material Mg _2.25 Ca _0.75 (PO ₄ ) ₂ . Next, the prepared calcium magnesium phosphate material Mg _2.25 Ca _0.75 (PO ₄ ) ₂ was crushed by a mortar, and then sieved with a 355 μm aperture sieve. After the sieve, it was ground with a ball mill for 10 minutes to make a powder, and the The powder is mixed with Ca(H ₂ PO ₄ ) ₂ ·H ₂ O at a molar ratio of 1:1 and stirred for 30 seconds to prepare self-curing calcium magnesium phosphate powder.

The third step is to prepare the collagen solution. The specific method is: add type I collagen fibers to 5mol/L acetic acid solution at a concentration of 3% (mass volume W/V), stir magnetically at 4°C for 24 hours to fully dissolve, and then dissolve the obtained solution into a semipermeable membrane Dialyze with double distilled water for 48 hours, replace the double distilled water every 6 hours, remove the acetic acid component, and make collagen solution.

The fourth step is to prepare artificially synthesized substance P polypeptide. The specific method is: use an automatic polypeptide synthesizer to artificially synthesize the substance P polypeptide according to the following amino acid sequence Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2.

The fifth step is to prepare substance P covalently cross-linked modified collagen matrix. The specific method is: using 1-ethyl-(3,3′-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide as covalent cross-linking agents, the substance P polypeptide, 1-ethyl-(3,3'-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide are mixed according to the molar ratio of 1:1.2:0.6, and then the mixture is mixed according to the mass volume concentration of 1 %W/V was added into the collagen solution, firstly reacted with magnetic stirring for 24 hours, and then the semipermeable membrane was dialyzed with double distilled water for 72 hours to prepare substance P covalently cross-linked modified collagen matrix.

In the 6th step, the self-curing calcium magnesium phosphate powder and the citric acid solution of 0.5mol/L are adjusted and mixed according to the mass volume concentration of 3.0g/ml to make self-curing calcium magnesium phosphate paste, and then 60%: 40% volume ratio, mix the self-curing calcium magnesium phosphate paste with the covalently cross-linked modified collagen matrix of substance P, put it into a curing mold, and then place the root of the titanium implant core 1 and part of the crown 2 are inserted into the curing mold, pressurized to 200-300kPa, cured at 100% humidity for 24 hours, then frozen at -80°C for 12 hours, and vacuum freeze-dried for 48 hours. Wherein, the curing mold is 3mm more than the root diameter and height of the dental implant core respectively, so that the surface of the root 1 of the dental implant core is coated with self-curing calcium magnesium phosphate-SP bioactive collagen material, and then The dental implant is an immediate dental implant with biological activity of SP mobilizing stem cells and biological activity of simulating natural tooth periodontal healing.

In the present invention, the self-curing composite material based on calcium phosphate has good material compatibility and tissue compatibility, and has the following advantages for artificial tooth root preparation: it is easy to shape and process (including the overall material shape, the internal structure of the bracket and Scaffold surface morphology, etc.), adjustable material strength, controllable degradation rate, multiple functional loading (including as stem cell transplantation carrier, biological factor/drug loading and slow release carrier, etc.), both osteoconductive and osteoinductive activities. It has unique advantages for solving the periodontal healing problems of implants.

In addition to participating in pain transmission as a neurotransmitter, SP in the present invention is also widely distributed in bone marrow stromal cells, vascular endothelial cells, neutrophils, epithelial cells, etc., and plays a variety of roles, and is considered to be a systemic response messenger of trauma. It is an important molecule in mobilizing stem cells and promoting wound repair. SP also has the function of inducing angiogenesis, and its mechanism may include directly inducing the differentiation and proliferation of vascular endothelial cells, and indirectly recruiting and activating other cells related to angiogenesis through TNF-a signaling. SP also plays an important role in bone regeneration and bone turnover (turnover, bone resorption and bone formation). In vitro studies have shown that SP can stimulate the proliferation and differentiation of bone marrow stromal cells (bone marrow stromal cells, or BMSCs) in a concentration-dependent manner. Pharmacological studies have shown that SP has no adverse pharmacological effects or genotoxicity, and can be safely used in vivo for cell mobilization and treat. Based on the above characteristics, SP is a small molecular active peptide that is convenient and easy to obtain, has various functions, is safe and reliable, and has a good effect on artificial organ tissue engineering.

Simple SP polypeptides will be rapidly degraded in vivo and lose their activity. Therefore, in order to realize the biological effects of SP in vivo, appropriate delivery, positioning, and slow-release systems should be designed to control the functional effects of SP. In the present invention, SP is connected to collagen fibers by covalent cross-linking molecules, and its main advantages are as follows: ① Similar to extracellular matrix, it provides cells with a nanoscale three-dimensional microenvironment, which is conducive to cell adhesion and growth. ②The collagen is gradually degraded, the SP is released stably and slowly, and the stem cell mobilization effect is continuously produced. ③The three-dimensional collagen fiber network is compounded between the solidified calcium and magnesium phosphate crystals, simulating the cementum structure of the tooth root, forming a bionic artificial tooth root, and realizing tissue transformation in vivo by guiding + inducing.

In the present invention, the self-induced periodontal healing environment is constructed by artificial tooth root bioactive substances, which can induce the regeneration of endogenous periodontal support tissue after implantation, complete the transformation and reconstruction of artificial materials into autologous tissues, and finally form a stable Periodontal attachment support structures.

The content of specific embodiments is described for the convenience of those skilled in the art to understand and use the present invention, and does not constitute a limitation to the protection content of the present invention. Those skilled in the art can make appropriate modifications to the present invention after reading the content of the present invention. The protection content of the present invention shall be determined by the content of the claims. Without departing from the essence and protection scope of the claims, various modifications, changes and replacements to the present invention are within the protection scope of the present invention.

Claims (2)

1. a kind of manufacture method of the immediate implantation teeth with periodontal bioactivity, it is comprised the following steps：

(1) pure titanium or titanium alloy implant core are prepared, wherein, the planting body core includes bizet (1) and root (2), the hat There is screw (4) in portion (1), for fixing artificial corona (8), there is screw thread (5) outer surface of the root (2), for disperseing to sting Combined stress, wherein, the connecting portion of the bizet (1) and the root (2) has the step (3) of 0.8-1mm；

(2) self-curable calcium phosphate magnesium powder agent is prepared, specific method is：According to Mg: Ca=3: 1 mol ratio, by Mg (OH)₂With CaCO₃Mixing, MgHPO₄·3H₂O and CaHPO₄Mixing, then then two kinds of mixtures again will according to 1: 2 mixed in molar ratio Mixed material is sintered 5 hours at 1100 degrees celsius, prepares calcium phosphate magnesium material Mg_2.25Ca_0.75(PO₄)₂；By mortar Broken gained calcium phosphate magnesium material Mg_2.25Ca_0.75(PO₄)₂, then sieved with 355 μm of aperture sieves again, used again after screening Ball mill grinding is made powder, and mol ratio and Ca (H by the powder according to 1: 1 for 10 minutes₂PO₄)₂·H₂O is mixed 30 seconds, it is made self-curable calcium phosphate magnesium powder agent；

(3) collagen solution is prepared, specific method is：By I-type collagen fiber according to mass-volume concentration for 3%W/V is added In the acetic acid solution of 5mol/L, and the magnetic agitation dissolving at a temperature of 4 DEG C, it is then that solution is small with the dialysis 48 of pellicle distilled water When remove acetic acid composition, be made collagen solution；

(4) artificial synthesized Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 polypeptide is prepared, specific method is：Using automatic Peptide synthesizer according to following amino acid sequence The artificial synthesized Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 polypeptides of Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2；

(5) Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 covalent cross-linking modified collagen matrix is prepared, specific method is：With 1- ethyls-(3,3 '-dimethylamino third Base) phosphinylidyne diimine and N-hydroxy-succinamide be covalent crosslinking agent, by the Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 polypeptide, 1- ethyls-(3,3 '-diformazan Base aminopropyl) phosphinylidyne diimine and N-hydroxy-succinamide mix according to mol ratio 1: 1.2: 0.6, then press mixture According to mass-volume concentration in the 1%W/V addition collagen solutions, first magnetic agitation is reacted 24 hours, then pellicle is double steams Water dialysis is made Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 covalent cross-linking modified collagen matrix for 72 hours；

(6) according to mass volume ratio example it is 3.0g by the citric acid soln of self-curable calcium phosphate magnesium powder agent and 0.5mol/L: 1ml is adjusted to mix and is mixed and made into self-curable calcium phosphate magnesium paste, then is pasted the self-curable calcium phosphate magnesium with volume ratio 60%: 40% Agent is adjusted to mix and is mixed and made into bioactivity paste with the Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2 covalent cross-linking modified collagen matrix；

(7) two-part bioactivity paste cure under pressure mould is prepared, epimere is used to accommodate and fix the bizet (1), hypomere For accommodating the root (2) and the bioactivity paste, making the surface of the root (2) has the biology of 3mm thickness living Property paste coating, it is then that two-part bioactivity paste pressurization fixed line mould is stitched together and be forced into 200- 300kPa, being placed in 100% humidity environment makes the phosphoric acid calcium and magnesium paste curing for 24 hours, is freezed 12 hours then at -80 DEG C, vacuum Freeze-drying 48 hours, the collagen component in crystallizing phosphoric acid calcium and magnesium is solidified into dimensional fibre network-like structure, is made with imitative The artificial tooth root of raw natural teeth root of the tooth cementum structure；

(8) artificial corona (8) is prepared, makes its form similar to agomphosis form, the bizet (1) is fixed on by screw (7), i.e., Can be made into immediate implantation teeth.

2. there is the manufacture method of the immediate implantation teeth of periodontal bioactivity as claimed in claim 1, wherein, finally described The outer surface of root (2) forms the thick bioactive layers (6) of 3mm.