JPS5854023A - Inorganic fiber - Google Patents

Abstract

PURPOSE:Inorganic fibers, having a specific (Ca/P) molar ratio and the content of (CaO+P2O5) in a specific range, having improved biocompatibility, capable of uniting with the hard tissue in the living body in a short time without causing foreign body reactions, and suitable for fillers in lost parts of bones and gaps. CONSTITUTION:A raw material of phosphorus and calcium, e.g. calcium tetraphosphate, hydroxyapatite, quick lime or ammonium tertiary phosphate, is mixed with animal bones, kaolin, etc., at 0.3-4.0 (Ca/P) molar ratio and 80-15wt% (CaO+P2O5) content, and the resultant mixture is then melt spun to give the aimed fibers. Preferably, the resultant fibers are treated with an aqueous solution, e.g. diammonium hydrogenphosphate, to deposit the calcium phosphate compound on the fibrous surfaces. EFFECT:Very easily adapted to lost parts of bones in a complicated shape.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides bone defects and voids that have good compatibility with living organisms, have the ability to form new bone, and can be extremely easily adapted to bone defect sites with complex shapes. Concerning inorganic fibers as fillers.

In the field of surgery or orthopedics, defects or voids are created in bones due to fractures or removal of bone tumors, and even in the field of dentistry, alveolar +1i! This often occurs when the jawbone is wasted due to leakage and a prosthesis is required for the area. .

Conventionally, in such cases, the patient's own iliac bone, etc. was removed and the bone defect site was filled [7] In many 'AA fi' methods, the bone tissue defect or void was filled and the recovery of the tissue was accelerated. There is.

However, in order to use this method, it is necessary to remove one part of the normal bone tissue other than the damaged area, which may cause pain to the patient and require a great deal of labor during the surgery. Furthermore, if the bone defect is large (11), it is not always possible to collect enough autologous bone to fill it, and it is necessary to use some kind of substitute to make up for the shortage. Substitutes for this include /r, Toge allograft;

Although there is foreign bone, there are still problems such as rejection reactions with the implanted living tissue, and the postoperative course is not always positive, so it has not yet reached the stage of practical use.

For this reason, artificial materials that have excellent biocompatibility when filled into bone defects and voids, promote the function of ashes in the defect and surrounding areas, and repair and restore the structural functions of bone tissue defects. development is desired.

Various metal alloys and organic substances have been used as hard tissue substitutes for living organisms, but they are said to deteriorate due to dissolution in the living environment, to be toxic to living organisms, and to be accompanied by foreign body reactions. Ceramic materials, which have excellent compatibility with living organisms and do not have the above-mentioned drawbacks, are now being used. Among these ceramic materials, artificial bones and artificial tooth roots made of sintered bodies or single crystals of alumina, carbon, tricalcium phosphate, or hydroxyapatite, which have excellent biocompatibility, are beginning to attract attention. .

However, all of these ceramic implant materials have the drawbacks that are common to ceramic materials, such as being hard and brittle, and so far they have not reached a state where they can be put to practical use. Furthermore, attempts have been made to fill bone defects with ceramic blocks made of these sintered compacts or single crystals, but when filling bone defects with complex shapes, there is a gap between the blocks and bone tissue. Because uniform gaps remain, the purpose of filling cannot be achieved. On the other hand, in the case of alumina, for example, since it is significantly harder than bone tissue, bone resorption occurs around the filling material due to stimulation. There are some problems, and it has not been put into practical use for a long time.

Therefore, the second objective of the present invention is to provide an inorganic fiber that is excellent in biocompatibility and can be used to fill bone defects and voids that integrates with biological hard tissue in a short period of time without causing any foreign body reaction. Another object of the present invention is an inorganic fiber that is a filling material for bone defects and voids that promotes the ashes action in the filled area and quickly repairs and restores the structure and function of the bone tissue defect. Our goal is to provide the following.

Still another object of the present invention is to provide an inorganic fiber that is a filling material for bone defects and voids that can be very easily formed into a shape suitable for the shape of the filling site.

According to the present invention, the Ca/P molar ratio (the atomic ratio of Ca/P, the same hereinafter) is 0.3 or more and 4.0 or less, and CaO
+ An inorganic fiber containing 80% by weight or less and 15% by weight or more of P 205 and an inorganic fiber having a calcium phosphate compound on its surface are provided.

First, the Ca/P molar ratio is 0.3 to 4.0, and Ca
O + P2O5 80 to 15% by weight (hereinafter simply referred to as %)
) The contained inorganic fibers will be explained.

As raw materials for phosphorus and calcium in the inorganic fiber of the present invention, tetracalcium phosphate, hydroxyapatite,
Compounds containing phosphorus and calcium such as tricalcium phosphate, tricalcium phosphate, monetite, etc. and compounds containing calcium such as quicklime, slaked lime, calcium carbonate, or triammonium phosphate, phosphoric acid-hydrogen One type or a mixture of two or more selected from phosphorus-containing compounds such as aluminum, sodium sinate, potassium phosphate, phosphoric acid, etc., and further selected from each of the above-mentioned calcium-containing compounds and phosphorus-containing compounds. Re7'? ,
11m or a mixture of two or more types can be used as appropriate.

The total of the components other than CaO and P2O is 20 to 8.
Fjl, aluminum as a raw material to be 5%.

1 selected from compounds including silicon, IJium, etc.
A mixture of two or more types of seeds can be used as appropriate. In place of these, naturally occurring substances such as animal bones and kaolin may also be used that do not contain components harmful to living organisms such as arsenic, cadmium, etc.
It can be used in small quantities.

The inorganic fiber of the present invention can be produced by, for example, appropriately mixing the above-mentioned raw materials, putting the mixture into a melting pot with a nozzle at the bottom, melting it, clarifying it, letting the melt flow out from the nozzle at the bottom, and then injecting high-pressure gas into it. By wiping it, you can make it into cotton-like fibers, and then pour the spill into a drum! , can be made into long fibers by cutting.

Due to this shape, when used as a filling material for bone defects and voids, the shape can be changed very easily and freely, and the surface area is smaller than that of lumps. Because of this, the amount of new bone generated can be increased.7 Furthermore, by forming the fiber into this shape, when the fiber is used as a filler, continuous pores can be provided, so that the bone-forming component can fill the fiber. As a result of penetrating into the interior of the material, the repair and recovery of the bone tissue defect site and the integration of the living hard tissue and the filler material can be significantly accelerated.

The inorganic fiber has a Ca/P of 0.3 to 4.0,
And it is necessary that the Ca0-)-PtOs content is in the range of 80 to 15%. If Ca/P is less than 0.3, the viscosity of the melt is too small and the fibers and eggplant are immersed.If Ca/P is more than 4.0, the viscosity of the melt is too small and the fibers and eggplant are immersed. 80% of the amount
If the melting point of the raw materials exceeds this, the melting point of both materials will become extremely high, making it impossible to melt them, or even if they can be melted, the viscosity of the melt will be too thick to make fibers, making it impossible to make fibers. . On the other hand, CaO+PtO*
If the content is less than 15%, the biocompatibility is poor,
Moreover, the ability to generate new bone is also lowered, and the repair and recovery of bone tissue is delayed, which is not preferable.

Although long fibers can be used as fillers for bone defects, etc., they can also be used as fillers for bone defects, etc., but they can be used in the same manner as woven fibers. < can be used by wrapping it around the defect or fracture site. By filling the bone defect with fibers and then wrapping the fibers around it in the form of a fabric, the healing period for repairing or recovering the bone defect can be shortened compared to when the bone defect is only filled with fibers. Ru.

The inorganic fiber of the present invention is preferably free of calcium phosphate compounds on its surface, and the effect of having a calcium phosphate compound on the surface of the inorganic fiber further improves the biocompatibility of the inorganic fiber and further enhances the ability to generate new bone. By increasing the size, the repair and recovery of the living bone tissue and the integration of the bone tissue and the filling material are made faster.

As a method for providing a calcium phosphate compound on the surface of an inorganic fiber, the inorganic fiber is mixed with an aqueous solution of phosphoric acid and an aqueous solution of ammonium hydrogen phosphate, ammonium dihydrogen phosphate, or trihydrogen phosphate. An aqueous solution of ammonium or a mixed solution thereof, or a mixture of these and an aqueous phosphoric acid solution or aqueous ammonia to a desired pH, and by immersion in this solution, the phosphoric acid groups present in the solution and inorganic fibers are eluted. A method can be used in which a calcium phosphate compound is precipitated on the surface of the fiber by reacting with calcium ions.

It is necessary that the pH of the solution containing a phosphoric acid group to precipitate a calcium phosphate compound on the surface of the inorganic fiber is between 2 and 7. This is because if the pH of the solution is less than 2, the inorganic fiber will deteriorate and the strength of the fiber will drop significantly, making it impossible to obtain a fiber with sufficient strength to be used as a filler. On the other hand, if plI exceeds 7, the amount of calcium phosphate compound precipitated on the surface of the inorganic fiber will be extremely small, so that no significant surface modification effect can be expected.

Although the type of calcium phosphate compound precipitated on the surface of the inorganic fiber cannot be determined in detail, the results of X-ray diffraction indicate that when the pH of the solution containing phosphate groups is low, plurashite is used; If it is high, it seems that apatite is the main component.

In addition, as a method for imparting a calcium phosphate compound to the blush of an inorganic fiber, a slurry of a calcium phosphate compound such as plurashite, tricalcium phosphate, hydroxyapatite, etc. is deposited on the surface of the inorganic fiber, and this is applied to the surface of the inorganic fiber. A method of fixing the calcium phosphate compound to the surface of the fiber by drying may also be used.

Surface modification can be performed not only on fibers but also on the aforementioned long fibers in the form of a woven fabric, and this surface-modified woven fabric is wrapped around the bone defect as described above. Of course, it is also possible to use it for methods etc.

The inorganic fiber according to the present invention is not only used in the fields of surgery and orthopedics, but also in dentistry to prevent alveolar ridge decline after tooth extraction, or to bone defects around tooth roots caused by alveolar pyorrhea, etc. Of course, it is also possible to use it as a treatment material for water containing sicic acid groups.

The present invention will now be explained in more detail with reference to Examples.

[Example 1] An attempt was made to produce a 151+ fiber by flowing out the molten material through the nozzle of a crucible and winding the molten material around a drum. The results are shown in Table 1.

As a result, when Ca/P was 0.2, none of r1 could be made into fibers, but this was because the utilization of the melt when these were melted was too low. On the other hand, Ca/
(P is 03): When i is 1.7, Ca O+P, 0.
If it is 90 yen, it becomes a molten material, but when making fibers from these, it was difficult to break the thread and make it into a fiber with 111 (continued).Ca / L ) is 4.0, and when CaO+P,O, is 90 V, and when Ca/P is 5.0, 1fCF
-L 170 (Hara Kyo 1 mixed with 1-C1/Cte also did not melt, making it impossible to obtain fibers.

In any case other than those listed above,
By cutting the yarn, we were able to create long fibers.

Table 1 Table 1 (Thin) A1 [1 person and Kai Q1 Tari 2] Test No. 1'x7, 9 in Practice 1 Riri 1. ] 1. ]
, 3゜17.19Fiber artificially prepared on the femur of all human beings (11 parts (3L・IILψX 4
The condition of the bone defect was observed after 12 weeks. As a result, 7,9,13゜17 on the exam.
．． 19 fibers were used, and in each case they were almost integrated with the surrounding skeletal area,
The boundary between the filler and the surrounding bone tissue is precise and tight. However, when the fiber of Test A11 was used, only a slight amount of new bone formation was observed on the surface of the filled fiber, and the surrounding bone tissue and the filling material could be clearly distinguished.

[Example 3] Test JIG in Example 1, 7. 13. Prepare a melt in a crucible with a nozzle at the bottom in the same manner as in Example 1 using raw materials with the same composition as in Example 19, flow out the melt from the nozzle at the bottom, and blow the same pressure air over the crucible. In this way, we attempted to create cotton-like fibers.

As a result, flocculent fibers could be obtained in all cases.

Artificially created bone defects in these music-sized femurs (3+
amψX 411'l waste L) was filled, and the subsequent progress was observed. As a result, in either case, after filling 4
It was observed that a large amount of new bone had been generated on the fiber surface that had already been filled within a week.

[Example 4] Using the fibers prepared in Tests A7 and 13.19 in Example 1, the fibers were treated with pI (1,0, 2,0.

4.0. 6.0. 7.0,8. (Surface treatment of the fiber is carried out for 30 minutes each in the aqueous solution that has been adjusted to +).The surface of the fiber thus treated with K t and iron is observed with a scanning microscope and a submicroscope. However, in all cases, the fiber surface was corroded and large irregularities were observed for the fiber treated with pH 1,0. Almost no precipitate was observed. pltl 2.0, 4.0, 6.
When treated with 0 and 7.0, the fiber surface was covered with :'1 precipitates, but □゛: Among them, p
]-14,0,6,0, the surface was more uniformly covered with precipitates.

Table 2 shows the tensile strength when the fibers produced in Test A13 were treated with each of the above p11.

The results in Table 2 show that when the pH was 10, the tensile strength was significantly reduced.

[Example 5] Test A in Example 1 7. , 19 and the fiber prepared in the same manner as in Example 4 at pH 2, 0, 4, 0, 6, 0, 7, 0°s, o v
A bone defect (3 mm x 4 mm) artificially created in a dog's femur was filled with the fibers that had been surface-treated using the above methods, and the state of new bone formation was observed after 3 weeks had elapsed. did.

As a result, compared to the fibers without surface treatment, the fibers with the surface treatment produced a larger amount of new bone in all cases, except for the case with the surface treatment at pH 8.0. It was done. When P f18.0 and Table 1m treatment No. 1 (1J) were applied, the line resistance was the same as when using No. 1 without surface treatment.

Patent applicant: Mitsubishi Mining and Cement Co., Ltd.
Voluntary) November 2, 1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case 1982 Patent Application No. 1461822, Name of the invention Inorganic fiber3, Representative of the person making the amendment Irikiri Kobayashi4 , Agent Address: 165 03-999-2075
5-15-3 Saginomiya, Nakano-ku, Tokyo Name (8373)
) Patent attorney 1) Sadao Naka 5. Date of amendment order
Voluntary amendment 8, contents of amendment (1) “Na 211 P O4-1 is changed to 1-NaH2P0” in the row of test consideration 21 in Table 1 on page 14 of the specification
Corrected to 4j. ) that's all

Claims (2)

[Claims] (1) Inorganic fiber characterized by having a Ca/P molar ratio of 0.3 or more and 4.0 or less, and containing CaO + Pt Os in an amount of 80% by weight or more and 15% by weight or more (2) The inorganic fiber according to claim 1, wherein the inorganic fiber has a calcium phosphate compound on its surface.