JP3423951B2 - Calcium phosphate hardened powder - Google Patents
Calcium phosphate hardened powderInfo
- Publication number
- JP3423951B2 JP3423951B2 JP07184394A JP7184394A JP3423951B2 JP 3423951 B2 JP3423951 B2 JP 3423951B2 JP 07184394 A JP07184394 A JP 07184394A JP 7184394 A JP7184394 A JP 7184394A JP 3423951 B2 JP3423951 B2 JP 3423951B2
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- JP
- Japan
- Prior art keywords
- powder
- phosphate
- ratio
- present
- calcium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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- Materials For Medical Uses (AREA)
- Dental Preparations (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、リン酸カルシウム系硬
化体用粉剤に係り、さらに詳しくは医科用あるいは歯科
用セメントの材料又は骨補填材などに有用なリン酸カル
シウム系硬化体用粉剤に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder for a calcium phosphate-based hardened material, and more particularly to a powder for a calcium phosphate-based hardened material useful as a material for medical or dental cement or a bone filling material.
【０００２】[0002]
【従来技術及びその問題点】α−リン酸三カルシウム
〔Ca3(PO4)2 〕、リン酸四カルシウム〔Ca4(PO4)2O〕あ
るいはこれらの２種の混合物が水硬性を示し、硬化体を
形成するため、この性質を利用して歯科用あるいは医科
用セメントとしてリン酸カルシウム粉末を用いることが
盛んに研究されている。従来、強度の高い硬化体を得る
には、リン酸カルシウム系化合物から成る粉剤をできる
だけ均一な組成とすることが望ましいと考えられてい
た。他方、リン酸カルシウムよりなる粉剤と混練される
硬化液としては、混練物のpHが低下すると、生体組織へ
の刺激が生じるため、中性領域において硬化反応を進行
させることが望まれている。Prior art and its problems: α-tricalcium phosphate [Ca 3 (PO 4 ) 2 ], tetracalcium phosphate [Ca 4 (PO 4 ) 2 O] or a mixture of these two types shows hydraulic properties. In order to form a hardened body, the use of calcium phosphate powder as a dental or medical cement has been actively studied by utilizing this property. Conventionally, in order to obtain a cured product having high strength, it has been considered desirable to make the powdery agent comprising a calcium phosphate compound to have a composition as uniform as possible. On the other hand, as a hardening liquid to be kneaded with a powdery agent made of calcium phosphate, when the pH of the kneaded material is lowered, irritation to living tissues occurs, and therefore it is desired to advance the hardening reaction in the neutral region.
【０００３】このような観点から、特公平５−２８６３
１号公報には、α−リン酸三カルシウムとリン酸水素カ
ルシウムとの混合物から成り、Ｃａ／Ｐ比が１．４７０
より大きく、１．４９８以下の混合粉剤と、液剤とを混
練することによってリン酸カルシウム系硬化体を製造す
る方法が開示されている。この方法では、硬化反応が比
較的穏和に進行するなどの利点が得られるものの、硬化
時間が長く、生体内で吸収性が早すぎて骨補填剤として
使用した場合に新生骨の形成に追いつかないという問題
点があった（第４７回口腔科学会抄録９６頁、ＩＤ−１
５「α−ＴＣＰ硬化体の長期埋入例の検討」、倉科憲治
ら著）。From this point of view, Japanese Patent Publication No. 5-2863
No. 1 discloses a mixture of α-tricalcium phosphate and calcium hydrogen phosphate having a Ca / P ratio of 1.470.
A method for producing a calcium phosphate-based cured product by kneading a mixed powder agent having a larger size of 1.498 or less and a liquid agent is disclosed. Although this method has the advantage that the hardening reaction proceeds relatively mildly, the hardening time is long and the absorbability in vivo is too fast to catch up with the formation of new bone when used as a bone filling material. There was a problem (Abstracts of the 47th Oral Sci., 96 pages, ID-1
5 "Study of long-term embedding cases of cured α-TCP," written by Kenji Kurashina et al.).
【０００４】[0004]
【発明の目的】本発明は、上記従来技術の問題点を解消
し、硬化時間が速く、ｐＨが中性域の混練物が得られ、
高い強度を有し、新生骨が形成されるまで高い強度を維
持しうるリン酸カルシウム系硬化体を製造しうる粉剤を
提供することを目的とする。The object of the present invention is to solve the above-mentioned problems of the prior art, to obtain a kneaded product having a fast curing time and a neutral pH range.
It is an object of the present invention to provide a powder agent having high strength and capable of producing a calcium phosphate-based hardened body capable of maintaining high strength until new bone is formed.
【０００５】[0005]
【発明の概要】本発明者らは、鋭意研究の結果、α−リ
ン酸三カルシウム及びリン酸四カルシウムとともにリン
酸水素カルシウム〔無水物（ＣａＨＰＯ4 ）又は２水和
物（ＣａＨＰＯ4 ・２Ｈ2 Ｏ）〕を加えた３成分系の粉
剤が上記目的に合致するものであることを見出し、本発
明を完成した。すなわち、本発明による粉剤は、主成分
としてα−リン酸三カルシウム、リン酸四カルシウム及
びリン酸水素カルシウムを含有し、Ｃａ／Ｐ比が１．４
０〜１．８０であることを特徴とする。SUMMARY OF THE INVENTION As a result of earnest research, the present inventors have found that calcium hydrogen phosphate [anhydrous (CaHPO 4 ) or dihydrate (CaHPO 4 .2H 2 ) together with α-tricalcium phosphate and tetracalcium phosphate. The present invention has been completed by finding that a three-component type powder containing O)] meets the above object. That is, the powder according to the present invention contains α-tricalcium phosphate, tetracalcium phosphate and calcium hydrogen phosphate as main components and has a Ca / P ratio of 1.4.
It is characterized by being 0 to 1.80.
【０００６】本発明において粉剤は、上記のように、α
−リン酸三カルシウム、リン酸四カルシウム及びリン酸
水素カルシウムの３成分を主成分とするものである。使
用するα−リン酸三カルシウム及びリン酸四カルシウム
は、それぞれ別個に公知方法で製造したものであっても
よいし、あるいはハイドロキシアパタイトを１１５０℃
〜１４５０℃の温度で減圧条件下に焼成して得られたα
−リン酸三カルシウムとリン酸四カルシウムとの混合物
を用いてもよい。また、リン酸水素カルシウムとして
は、公知の任意の方法で製造されたものを使用すること
ができ、無水物又は２水和物であってよい。上記３種の
リン酸カルシウム系化合物は、純品である必要はなく、
合成過程で生じる不純物を多少含んでいても差支えな
い。In the present invention, the dust is, as described above, α
-The main component is three components of tricalcium phosphate, tetracalcium phosphate and calcium hydrogen phosphate. The α-tricalcium phosphate and tetracalcium phosphate to be used may be separately produced by known methods, or hydroxyapatite at 1150 ° C.
Α obtained by firing under reduced pressure conditions at a temperature of ˜1450 ° C.
-A mixture of tricalcium phosphate and tetracalcium phosphate may be used. Further, as the calcium hydrogen phosphate, one produced by any known method can be used, and it may be an anhydride or a dihydrate. The above three types of calcium phosphate-based compounds need not be pure products,
It does not matter if some impurities generated in the synthesis process are included.
【０００７】本発明による粉剤は、上記の３成分の他
に、必要に応じてさらに、ハイドロキシアパタイト、フ
ッ素アパタイト、β−リン酸三カルシウム、ピロリン酸
カルシウムなどを含有していてもよい。しかし、本発明
による粉剤は、Ｃａ／Ｐ比が１．４０〜１．８０である
ことが必要であり、１．４０〜１．４７であることが好
ましく、１．４４であることがより好ましい。Ｃａ／Ｐ
比が１．４０未満、あるいは１．８０を超えると、硬化
反応が進行し難く、また、転化もスムーズに進行しな
い。In addition to the above three components, the powder according to the present invention may further contain hydroxyapatite, fluoroapatite, β-tricalcium phosphate, calcium pyrophosphate, etc., if necessary. However, the powder according to the present invention needs to have a Ca / P ratio of 1.40 to 1.80, preferably 1.40 to 1.47, and more preferably 1.44. . Ca / P
If the ratio is less than 1.40 or exceeds 1.80, the curing reaction is difficult to proceed and the conversion does not proceed smoothly.
【０００８】本発明による粉剤は、中性域のｐＨを有
し、水又は無機酸若しくは有機酸を含む水溶液と混練す
ることによって硬化し、平均粒径が従来の３倍以上大き
くても同等な硬化時間で硬化し、強度の高い硬化体を生
じる。また、リン酸カルシウム系化合物は、ハイドロキ
シアパタイト又はリン酸八カルシウムへの転化反応によ
り硬化するが、本発明の粉剤中の３成分の転化反応がそ
れぞれに進行するので、上記Ｃａ／Ｐ比の範囲の中で上
記３成分の配合割合を調整することにより硬化時間を調
節することができ、生体内で安定で安全な硬化体を提供
することができる。The powder according to the present invention has a pH in the neutral range and is hardened by kneading with water or an aqueous solution containing an inorganic acid or an organic acid. It cures in the curing time to give a cured product with high strength. Further, the calcium phosphate-based compound is hardened by the conversion reaction to hydroxyapatite or octacalcium phosphate, but since the conversion reaction of the three components in the powder of the present invention progresses in each case, it falls within the range of the above Ca / P ratio. By adjusting the mixing ratio of the above three components, the curing time can be adjusted, and a stable and safe cured product in vivo can be provided.
【０００９】さらに、本発明による粉剤は、必要に応じ
てＸ線造影剤、抗菌剤等を含有することができる。Ｘ線
造影剤としては、特に制限はなく各種のものを使用で
き、例えば、硫酸バリウム、塩基性炭酸ビスマス、ヨー
ドホルムなどが挙げられ、これらの１種以上を使用する
ことができる。また、抗菌剤としては、ヨードホルム、
クロルヘキシジンなどが挙げられる。Further, the powder according to the present invention may contain an X-ray contrast agent, an antibacterial agent, etc., if necessary. There are no particular limitations on the X-ray contrast agent, and various types can be used, and examples thereof include barium sulfate, basic bismuth carbonate, and iodoform, and one or more of these can be used. In addition, as an antibacterial agent, iodoform,
Examples include chlorhexidine.
【００１０】[0010]
【実施例】次に、実施例に基づいて本発明をさらに詳細
に説明するが、本発明はこれによって制限されるもので
はない。The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereby.
【００１１】実施例１
下記の粉剤を作製した。
試験粉剤
炭酸カルシウムとγ−ピロリン酸カルシウムの固相反応
により合成した平均粒径が５μｍで、Ｃａ／Ｐ比が１．
５のα−リン酸三カルシウム（以下、α−ＴＣＰと略記
する）。
試験粉剤
炭酸カルシウムとγ−ピロリン酸カルシウムの固相反応
により合成したα−ＴＣＰ９ｇとリン酸水素カルシウム
２水和物（以下、ＤＣＰＤと略記する）５ｇとを混合し
て得た平均粒径が５μｍで、Ｃａ／Ｐ比が１．３３の混
合物。Example 1 The following powder was prepared. The test powder calcium carbonate and γ-calcium pyrophosphate were synthesized by the solid phase reaction to have an average particle size of 5 μm and a Ca / P ratio of 1.
Α-tricalcium phosphate of 5 (hereinafter abbreviated as α-TCP). An average particle size of 5 μm obtained by mixing 9 g of α-TCP synthesized by a solid-phase reaction of test powder calcium carbonate and γ-calcium pyrophosphate with 5 g of calcium hydrogen phosphate dihydrate (hereinafter abbreviated as DCPD) , A mixture with a Ca / P ratio of 1.33.
【００１２】試験粉剤
ハイドロキシアパタイトを１２００℃で減圧下に焼成し
て得たα−ＴＣＰとリン酸四カルシウム（以下、ＴｅＣ
Ｐと略記する）との混合物から成り、平均粒径が１８μ
ｍで、Ｃａ／Ｐ比が１．６７の混合粉剤。
試験粉剤（本発明品）
試験粉剤１０ｇにＤＣＰＤ５．２ｇを混合して得た平
均粒径が１７μｍで、Ｃａ／Ｐ比が１．４４の混合粉
剤。Α-TCP and tetracalcium phosphate (hereinafter referred to as TeC) obtained by firing test powder hydroxyapatite at 1200 ° C. under reduced pressure.
Abbreviated as P) and has an average particle size of 18 μm.
m, a mixed powder with a Ca / P ratio of 1.67. Test Dust (Product of the Present Invention) A mixed dust having an average particle size of 17 μm and a Ca / P ratio of 1.44, obtained by mixing 10 g of the test dust with 5.2 g of DCPD.
【００１３】上記各粉剤の硬化反応時のｐＨ変動、硬化
時間及び硬化温度を下記の方法で測定し、結果を表１に
示す。
試験方法
ｐＨ変動は、各粉剤２ｇを４０℃の純水１００ｍｌ中に
投入し、スターラーで攪拌するが、攪拌開始時の水のｐ
Ｈと１時間攪拌後の水のｐＨを測定した。硬化時間は、
各粉体を３７℃の純水と粉剤／液剤の重量比（以下、Ｐ
／Ｌと略記する）＝１．６で練和し、各練和物の硬化時
間を測定した。The pH fluctuation, curing time and curing temperature of each of the above powders during the curing reaction were measured by the following methods, and the results are shown in Table 1. Test method As for pH fluctuation, 2 g of each powder is put into 100 ml of pure water at 40 ° C. and stirred with a stirrer.
The pH of water after stirring with H for 1 hour was measured. The curing time is
Weight ratio of each powder to pure water at 37 ° C and powder / liquid agent (hereinafter, P
Abbreviated as /L)=1.6, and the curing time of each kneaded product was measured.
【００１４】[0014]
【表１】 [Table 1]
【００１５】表１に示した結果から、本発明の粉剤は、
中性域のｐＨで硬化反応が進行し、硬化時間が短く、通
常の硬化温度で硬化することが分かる。From the results shown in Table 1, the powder of the present invention is
It can be seen that the curing reaction proceeds at a pH in the neutral range, the curing time is short, and the curing takes place at a normal curing temperature.
【００１６】実施例２
実施例１で調整した試験粉剤〜のそれぞれを、２０
重量％クエン酸水溶液とＰ／Ｌ＝２．０で練和し、約３
ｇの円柱状硬化体（直径９ｍｍ、長さ２０ｍｍ）を６個
ずつ作製した。各硬化体をそれぞれ１００ｍｌの生理食
塩水中に投入し、３７℃で２４時間浸漬した後、生理食
塩水のｐＨ及び硬化体のヌレ圧縮強度を測定した。それ
ぞれ６個の測定値から平均値を求め、結果を表２に示
す。Example 2 Test powders prepared in Example 1 to 20
Knead with a wt% citric acid aqueous solution at P / L = 2.0, and
Six column-shaped cured bodies of g (diameter 9 mm, length 20 mm) were produced. Each of the cured products was put into 100 ml of physiological saline and immersed at 37 ° C. for 24 hours, and then the pH of the saline and the wet compressive strength of the cured product were measured. The average value was calculated from 6 measured values, and the results are shown in Table 2.
【００１７】[0017]
【表２】 [Table 2]
【００１８】表２に示した結果から、本発明の粉剤であ
る試験粉剤は、従来より低い酸濃度の液剤と混練して
も、また、平均粒径が比較的大きい粉剤を用いても、従
来より著しく高いヌレ圧縮強度を有する硬化体を生じる
ことが分かる。殊に、試験粉剤と試験粉剤（α−Ｔ
ＣＰとＴｅＣＰとの混合物）とを対比すると、平均粒径
はほぼ同等であるが、本発明の粉剤である試験粉剤を
用いた硬化体は、約３倍高い圧縮強度を示しており、ま
た、試験粉剤（α−ＴＣＰとＤＣＰＤとの混合物）と
比較すると、本発明の粉剤である試験粉剤を用いた硬
化体は、平均粒径は３倍以上大きいにもかかわらず、６
倍以上高い圧縮強度を示した。From the results shown in Table 2, the test powder, which is the powder of the present invention, was not mixed with the liquid powder having an acid concentration lower than that of the conventional powder, or the powder having a relatively large average particle diameter was used. It can be seen that it yields a cured body with a significantly higher wetting compressive strength. Especially, test powder and test powder (α-T
(Mixture of CP and TeCP), the average particle diameters are almost the same, but the cured product using the test powder, which is the powder of the present invention, shows about 3 times higher compressive strength, and Compared with the test powder (mixture of α-TCP and DCPD), the cured product using the test powder of the present invention has a mean particle size of 3 times or more, but 6
The compression strength was more than twice as high.
【００１９】[0019]
【発明の効果】本発明による粉剤を用いると、従来より
低い酸濃度の液剤を用いても硬化時間が速く、ｐＨを硬
化反応中も硬化反応終了後も常に中性域にすることがで
き、生体組織に対する刺激が少なく、しかも、平均粒径
が従来の３倍以上であっても強度の高い硬化体が得ら
れ、生体内での吸収性はあまり速くないため、新生骨が
形成されるまで高い強度を維持しうる品質のよい硬化体
が得られる。本発明によれば、医科用あるいは歯科用セ
メントの材料又は骨補填材などに好適なリン酸カルシウ
ム系硬化体を提供することができる。When the powder according to the present invention is used, the curing time is faster even when a liquid agent having an acid concentration lower than that of the conventional one is used, and the pH can be kept in the neutral range both during the curing reaction and after the completion of the curing reaction. Until the formation of new bone, the hardened body with less irritation to living tissue and high strength can be obtained even if the average particle size is 3 times or more of the conventional one, and the absorbability in the living body is not so fast. A cured product of high quality that can maintain high strength can be obtained. According to the present invention, it is possible to provide a calcium phosphate-based hardened material suitable as a material for medical or dental cement, a bone filling material, or the like.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平６−172008（ＪＰ，Ａ) 特開 平２−48479（ＪＰ，Ａ) 特開 平５−839（ＪＰ，Ａ) 特開 平４−83748（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C04B 12/02 C04B 28/34 A61K 6/033 A61L 27/00 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-172008 (JP, A) JP-A-2-48479 (JP, A) JP-A-5-839 (JP, A) JP-A-4- 83748 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) C04B 12/02 C04B 28/34 A61K 6/033 A61L 27/00
Claims (4)
酸四カルシウム及びリン酸水素カルシウムを含有し、Ｃ
ａ／Ｐ比が１．４０〜１．８０であり、中性域のｐＨで
硬化反応が進行することを特徴とするリン酸カルシウム
系硬化体用粉剤。1. Mainly containing α-tricalcium phosphate, tetracalcium phosphate and calcium hydrogen phosphate, and C
a / P ratio of 1.40 to 1.80, at pH in the neutral range
A powder for a calcium phosphate-based cured product, which is characterized in that a curing reaction proceeds .
請求項１記載の粉剤。2. The powder according to claim 1, which has a Ca / P ratio of 1.40 to 1.47.
載の粉剤。3. The powder according to claim 1, which has a Ca / P ratio of 1.44.
含有する請求項１、２又は３記載の粉剤。4. The powder according to claim 1, further comprising an X-ray contrast agent and / or an antibacterial agent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP07184394A JP3423951B2 (en) | 1994-04-11 | 1994-04-11 | Calcium phosphate hardened powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP07184394A JP3423951B2 (en) | 1994-04-11 | 1994-04-11 | Calcium phosphate hardened powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07277790A JPH07277790A (en) | 1995-10-24 |
| JP3423951B2 true JP3423951B2 (en) | 2003-07-07 |
Family
ID=13472233
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP07184394A Expired - Fee Related JP3423951B2 (en) | 1994-04-11 | 1994-04-11 | Calcium phosphate hardened powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3423951B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003052804A (en) * | 2001-08-09 | 2003-02-25 | Ichiro Ono | Manufacturing method for implant and implant |
| JP2003070816A (en) | 2001-08-30 | 2003-03-11 | Pentax Corp | Designing method for implant, and implant |
-
1994
- 1994-04-11 JP JP07184394A patent/JP3423951B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07277790A (en) | 1995-10-24 |
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