CN102688522A - Novel mixed bone cement - Google Patents

Abstract

The invention provides novel mixed bone cement. The novel mixed bone cement provided by the invention provides a strong support for the bone at the initial stage, and gradually the rigidity of PMMA bone cement is decreased with the ingrowth of cancellous bone at the later stage, so that the implant has elastic modulus similar tothe cancellous bone, and has both mechanical and biological fixation, thus long-term complications of PMMA bone cement can be reduced. The characteristics of high viscosity and low liquidity of the mixed bone cement are very important in percutaneousvertebroplasty and percutaneous kyphoplasty (PVP and PKP), and the occurrence of bone cement leakage can be reduced.

Description

New hybrid type bone cement

Technical field:

The present invention relates to medical instruments field, more specifically relate to a kind of bone implant material of orthopaedics, department of cerebral surgery and the department of stomatology, play the effect of bone grafting, bone support and bone adhesion.Be applied to bone grafting, joint replacement and overhaul, percutaneous kyphoplasty art fields such as (PVP and PKP).

Background technology:

Main component is that polymethyl methacrylate (PMMA) " bone cement " comes across early 1960s the earliest, is the clinical bone cementum commonly used of orthopaedics.PMMA is much in daily life, and lucite just is made up of PMMA, extremely is difficult to be absorbed by the body.Therefore, be difficult to the imagination permanent implantation of a lucite can not had problems in damaged, owing to can not find better succedaneum, the orthopedist can only continue to use.

Polymethyl methacrylate (PMMA) bone cement intensity, stretch-proof and anti-impact force make the PMMA bone cement cause various far and near phase complication all far above spongy bone with the discordant mechanical property of skeleton.Mainly comprise:

1.PMMA bone cement is a kind of organic high molecular compound material.It is to form through polyreaction with monomers methyl methacrylate and polymethyl methacrylate.Monomer wherein has cytotoxicity, can make blood pressure drops behind the entering blood, and pulse is accelerated, collapse, even cardiac arrest.

2. because bone cement discharges great amount of heat at process of setting after injecting medullary cavity, blood and fat remaining in the medullary cavity expand in the back that is heated, and cause that the pulp cavity internal pressure raises, and can make in the fatty intravasation to cause thromboembolism.

3. the medullary cavity internal pressure increases the result who causes neural reflex.

4.PMMA the bone-cement biological compatibility is relatively poor, mechanical property is with bigger from body bone gap, and its comprcssive strength is too high, therefore can not the fusion of bone property, at a specified future dately can take place looseningly, and produce complication such as abrasive dust disease.

For example: artificial joint needs " bone cement " and skeleton to bind, and nearly all runs into this type of consequence cases with severe in the operation.Therefore, the improvement to the PMMA bone cement has just become an important problem.In this process, occurred bone cement centrifugation technique, vacuum technique etc. in succession, but these technology do not change the chemical property of PMMA bone cement and the component of bone cement, thereby fail from overcome the defective of PMMA bone cement at all.

Seeking better bone cementum is materialogy expert and orthopedics expert's research focus and difficult point all the time, but does not find combination property to surpass the homogenous material of PMMA bone cement so far as yet.Therefore, a kind of new research thinking is just in molding---development " mixed type bone cement ".So-called " mixed type bone cement " refers in PMMA, add other materials of proper proportion, thereby reaches effects such as reducing PMMA monomer, reduction intensity, has clinical meaning energetically.If the other materials that adds also has other function, like the function of the growth that promotes bone, the mixed type bone cement can also possess some other function when having the adherent function of bone so, will become good filling material of bone.

Someone adds bead, charcoal fiber, sugar and tricalcium phosphate and allosome skeletal grain etc. in PMMA.But charcoal fiber, bead and PMMA bone cement are difficult for adhesion, are prone to get loose and increase the weight of to become flexible; The space that sugar, tricalcium phosphate stay after being absorbed descends the bone cement tensile strength; Can increase the mechanical strength of bone cement behind the adding allosome skeletal grain, but allograph bone exists the serious and potential pathophoresis risk of rejection.Therefore above each material all fails fundamentally to solve the deficiency of bone cement.The research of " mixed type bone cement " does not at present also form ideal mixing formula.

Therefore, this area exigence finds an effective new product to address the above problem.

Summary of the invention:

The object of the invention just provides a kind of new hybrid type bone cement.

In first aspect of the present invention: the component of " mixing bone cement " is provided, has been respectively:

1, polymethyl methacrylate (PMMA)

2, calcium sulfate (Calcium Sulfate)

3, hydroxyapatite (hydroxyapatite)

4, calcium phosphate (Tri-Calcium Phosphate)

Wherein, calcium sulfate, hydroxyapatite, calcium phosphate are good bone alternate materials, are the basic materials for preparing artificial bone at present, have excellent biological compatibility, and can with merge mutually from the body bone photo, accomplish the reconstruction of creeping substitution and bone.After above-mentioned material is sneaked into PMMA, not only can play and reduce the PMMA amount of monomer, reduce the effect of intensity, and can bring into play itself and the function of rebuilding, thereby fundamentally solve the loosening problem of PMMA bone cement from the mutual fusion and the bone of body bone.

In second aspect of the present invention: the ratio that each component is provided:

1, polymethyl methacrylate (PMMA): 60-85%

2, calcium sulfate (Calcium Sulfate): 1-24%

3, hydroxyapatite (hydroxyapatite): 1-35%

4, calcium phosphate (Tri-Calcium Phosphate): 1-35%

Under the aforementioned proportion situation, when effectively reducing the PMMA amount of monomer, kept the viscosity of PMMA, reduced intensity simultaneously, make the intensity of mixing bone cement approaching more from the body bone.

In the third aspect of the invention, purposes of the present invention is provided, it is damaged that it is used to fill various bones, or the cavity that causes of bone injury, and the bone of cavity and department of cerebral surgery of filling various teeth is damaged.

Description of drawings:

Accompanying drawing 1, accompanying drawing 2: shown the X-ray photograph behind the simple use PMMA bone cement;

Accompanying drawing 3, accompanying drawing 4: shown the X-ray photograph after use mixes bone cement;

Fig. 5: shown the mixing bone cement that microscopically is observed.

The specific embodiment:

This project is found in CC; With 20% " bone is prone to give birth to " (TradeMark CEM) (50-60% calcium sulfate; The 20-25% hydroxyapatite, the 20-25% calcium triphosphate) be added into " the mixed type bone cement " that form behind the 80%PMMA, have the viscosity height; Mobile low, the characteristics of mix homogeneously.1991; Fur coat generation waits quietly the decalcification skeletal grain is mixed in the bone cement by a certain percentage, through scanning electron microscopic observation, finds that osseous granules interconnects in many zones; Form the tunnel that is communicated with; Can supply bone structure to grow into, through observing the postoperative passage that a large amount of osseous tissues constitute along skeletal grain in the time of 3 months grow into bone cement deep layer and visible lamellar bone structure." bone be prone to give birth to " in this experimentation has bone inductive effect equally, and not can with body generation rejection, mixes easily with PMMA, the use feasibility is higher in the art.Microscopically is observed and is seen that " bone is prone to give birth to " forms tunnel, equally distributed space in the PMMA polymer; Because of " bone be prone to give birth to " has preferably bone inductive effect and rejection can not take place; If spongy bone can follow passage that calcium phosphate forms and evenly grow in the PMMA bone cement; Then this type of " " initial stage will provide strong support for skeleton to the mixed type bone cement, and will be at a specified future date then along with growing into of spongy bone reduces the rigidity of PMMA bone cement gradually, implant is had and the similar elastic modelling quantity of spongy bone; Have machinery and biological fixation effect concurrently, can reduce PMMA bone cement long term complication.Its viscosity is high, and mobile low characteristics are particularly important in " percutaneous kyphoplasty art (PVP and PKP) ", can reduce the bone cement seepage and take place.

Experimental data is following:

In the PKP operation; The U.S. is produced " bone is prone to give birth to " powder and mix formation " mixing bone cement " with Tianjin product PMMA bone cement powder; Wherein " bone is prone to give birth to " accounts for 15%, fully mixes the stirring liquid that the back adds the PMMA bone cement, and the viscosity of observing composite slightly descends; Flowability descends simultaneously, tangible wire drawing phenomenon do not occur.Stir about 40 seconds of back composite is inserted in the patient body along service aisle, bolus infusion processes is smooth, and more single PMMA bone cement has obviously reduced the seepage phenomenon.Implemented 3 example operations altogether, the postoperative patient effect is all good.

Through simple use PMMA bone cement and adding " bone is prone to give birth to " postoperative X sheet contrast; Find that simple PMMA thigh cement postoperative is typical featheriness diffusion (seeing accompanying drawing 1, accompanying drawing 2); And it is smooth to mix the bone cement edge, greatly reduces the probability (seeing accompanying drawing 3, accompanying drawing 4) that the bone cement monomer gets into blood.The microscopically observation shows bone cement and " bone is prone to give birth to " mix homogeneously, helps the micropore formation (seeing accompanying drawing 5) that blood capillary is grown into.

Claims (5)

1. the invention provides a kind of a kind of novel artificial bone (" mixing bone cement ") that calcium sulfate (Calcium Sulfate), hydroxyapatite (hydroxyapatite), calcium phosphate (Tri-Calcium Phosphate) and polymethyl methacrylate (PMMA) is mixed by a certain percentage back formation.Following claim is arranged:

2. through mixing calcium sulfate (Calcium Sulfate), hydroxyapatite (hydroxyapatite), calcium phosphate (Tri-Calcium Phosphate) and polymethyl methacrylate (PMMA) by a certain percentage, form a kind of novel artificial bone (" mixing bone cement ").

3. above artificial bone (" mixing bone cement ") the blended ratio of each component is 60-85% polymethyl methacrylate (PMMA); 1-24% calcium sulfate (Calcium Sulfate); 1-35% hydroxyapatite (hydroxyapatite) and 1-35% calcium phosphate (Tri-Calcium Phosphate).

4. it is damaged that above artificial bone (" mixing bone cement ") can be used for filling various bones, or the cavity that causes of bone injury.

5. above artificial bone (" mixing bone cement ") can be used for filling the cavity of various teeth.

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