JPH06172007A - High-strength cement of calcium phosphate - Google Patents
High-strength cement of calcium phosphateInfo
- Publication number
- JPH06172007A JPH06172007A JP4328185A JP32818592A JPH06172007A JP H06172007 A JPH06172007 A JP H06172007A JP 4328185 A JP4328185 A JP 4328185A JP 32818592 A JP32818592 A JP 32818592A JP H06172007 A JPH06172007 A JP H06172007A
- Authority
- JP
- Japan
- Prior art keywords
- calcium phosphate
- phosphate
- strength
- cement
- weight
- 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.)
- Granted
Links
Landscapes
- Materials For Medical Uses (AREA)
- Dental Preparations (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は高強度リン酸カルシウム
に関し、更に詳細には医科歯科用に利用し得る高強度リ
ン酸カルシウムセメントに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to high-strength calcium phosphate, and more particularly to high-strength calcium phosphate cement that can be used in medical and dental fields.
【0002】[0002]
【従来の技術】リン酸カルシウムセメントは、37℃、
湿度100%の条件下で水と練和すると、短時間で硬化
することが知られている(特開昭64−37445号公
報)。該セメントはα型第3リン酸カルシウムと、第2
リン酸カルシウムとからなるセメントであるが、硬化の
前後でpHが変動せずに中性域を維持するため、生体刺
激性がなく、医科歯科用セメントとして有用であること
が知られている。しかし実用上十分な強度が得られない
という欠点がある。従来このようなセメントの強度を増
大するには、練和時の粉液比(P/L)を大きくする方
法が採られているが、一方では練和したセメントペース
トの粘度が上昇し、作業性の低下を招くという欠点もあ
る。更に該セメントは長期的に強度が劣化するという問
題がある。2. Description of the Related Art Calcium phosphate cement is
It is known that when it is kneaded with water under the condition of 100% humidity, it cures in a short time (Japanese Patent Laid-Open No. 64-37445). The cement comprises α-type tricalcium phosphate, second type
Although it is a cement composed of calcium phosphate, it is known to be useful as a medical / dental cement because it has no biostimulation because it maintains a neutral range without changing the pH before and after hardening. However, there is a drawback that practically sufficient strength cannot be obtained. Conventionally, in order to increase the strength of such cement, a method of increasing the powder-liquid ratio (P / L) at the time of kneading has been adopted, but on the other hand, the viscosity of the kneaded cement paste increases and There is also a drawback that it leads to a decrease in sex. Further, the cement has a problem that its strength deteriorates in the long term.
【0003】[0003]
【発明が解決しようとする課題】従って本発明の目的
は、生体刺激性がなく、高い粉液比で練和しても作業性
が低下せず、高強度かつ劣化のない高強度リン酸カルシ
ウムセメントを提供することにある。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a high-strength calcium phosphate cement that has no biostimulation, does not deteriorate workability even when kneaded at a high powder-liquid ratio, and has high strength and no deterioration. To provide.
【0004】[0004]
【課題を解決するための手段】本発明によれば、α型第
3リン酸カルシウム90〜70重量%と、第4リン酸カ
ルシウム5〜25重量%と、第2リン酸カルシウム5〜
10重量%とからなる粉体を含む高強度リン酸カルシウ
ムセメントが提供される。According to the present invention, 90 to 70% by weight of α-type tricalcium phosphate, 5 to 25% by weight of quaternary calcium phosphate, and 5 to 25% by weight of dibasic calcium phosphate.
Provided is a high strength calcium phosphate cement comprising a powder consisting of 10% by weight.
【0005】以下、本発明を更に詳細に説明する。The present invention will be described in more detail below.
【0006】本発明の高強度リン酸カルシウムセメント
は、α型第3リン酸カルシウム90〜70重量%と、第
4リン酸カルシウム5〜25重量%と、第2リン酸カル
シウム5〜10重量%とからなる粉体を含み、その各成
分の組合せとその量比を特徴とする。また、その他の添
加成分としては、例えばβ型第3リン酸カルシウム、リ
ン酸8カルシウム、第1リン酸カルシウム、ヒドロキシ
アパタイト等のリン酸カルシウム化合物及び生体親和性
に富む、アルミナ、ジルコニア等を含んでもよい。The high-strength calcium phosphate cement of the present invention contains a powder consisting of 90 to 70% by weight of α-type tertiary calcium phosphate, 5 to 25% by weight of fourth calcium phosphate, and 5 to 10% by weight of second calcium phosphate. It is characterized by the combination of the respective components and the amount ratio thereof. Further, other additive components may include, for example, β-type tribasic calcium phosphate, octacalcium phosphate, monobasic calcium phosphate, calcium phosphate compounds such as hydroxyapatite, and alumina, zirconia, and the like having high biocompatibility.
【0007】α型第3リン酸カルシウム及び第4リン酸
カルシウムは、水酸化カルシウム及びリン酸を所定モル
比にて用い、例えば水酸化カルシウムを水に懸濁し、リ
ン酸を添加して湿式合成後、乾燥して焼成、粉砕する等
の方法により得ることができる。また、第2リン酸カル
シウムは市販の第2リン酸カルシウム2水和物を用いる
ことができる。The α-type tribasic calcium phosphate and the tetrabasic calcium phosphate use calcium hydroxide and phosphoric acid in a predetermined molar ratio, for example, calcium hydroxide is suspended in water, phosphoric acid is added, wet synthesis is performed, and then dried. It can be obtained by a method such as firing, crushing, etc. Further, as the dicalcium phosphate, a commercially available dicalcium phosphate dihydrate can be used.
【0008】本発明において用いる第4リン酸カルシウ
ムは、α型第3リン酸カルシウム又は第2リン酸カルシ
ウムと反応して硬化させる成分であるが、本発明では特
にその強度の増加に利用する。第4リン酸カルシウムと
α型第3リン酸カルシウムとの反応若しくは第4リン酸
カルシウムと第2リン酸カルシウムとの反応は、α型第
3リン酸カルシウムと第2リン酸カルシウムとの反応に
比して遅いため、初期反応の遅延剤となる。従って第4
リン酸カルシウムを加えた場合、セメントと硬化液との
練和後、流動状態が長時間続き、その結果、より高い粉
液比でセメントと溶液とを練和できるため高強度化する
ことができる。また、第4リン酸カルシウムは遅硬性の
ため、長時間経過後に強度が発現され、硬化体の強度劣
化を防止することができる。尚第4リン酸カルシウムを
添加する効果について、更に次の事が挙げられる。α型
第3リン酸カルシウムと第2リン酸カルシウムとからな
るセメントは、各成分の配合量を変えてもCa/Pモル
比は、1.50〜1.00の範囲である。しかし、この
セメントは硬化後生体内でアパタイトに転化するので、
アパタイトのCa/Pモル比が1.67であることから
転化時に余分なPO4 3~が放出される事がわかる。これ
は局所的にpHが低下する等の生体に好ましくない作用
を及ぼす可能性がある。そこでPO4 3~を吸収するアル
カリ物質が必要とされる。第4リン酸カルシウムは、C
a/Pモル比が2.0で、アパタイトへの転化の際Ca
2+を放出してPO4 3~を吸収する。The quaternary calcium phosphate used in the present invention is a component which reacts with α-type tricalcium phosphate or dibasic calcium phosphate to be hardened, and in the present invention, it is particularly utilized for increasing its strength. Since the reaction between the fourth calcium phosphate and the α-type third calcium phosphate or the reaction between the fourth calcium phosphate and the second calcium phosphate is slower than the reaction between the α-third calcium phosphate and the second calcium phosphate, the reaction is delayed with respect to the initial reaction. Become. Therefore, the fourth
When calcium phosphate is added, the fluid state continues for a long time after the cement and the hardening liquid are kneaded, and as a result, the cement and the solution can be kneaded at a higher powder-liquid ratio, so that the strength can be increased. Further, since the quaternary calcium phosphate is slow-hardening, the strength is developed after a long time, and it is possible to prevent the strength deterioration of the hardened body. The effects of adding quaternary calcium phosphate are as follows. The cement composed of α-type tribasic calcium phosphate and dibasic calcium phosphate has a Ca / P molar ratio in the range of 1.50 to 1.00 even if the blending amount of each component is changed. However, since this cement is converted to apatite in vivo after hardening,
Ca / P molar ratio of hydroxyapatite is understood to be extra PO 4 3 ~ is released upon conversion because it is 1.67. This may have an unfavorable effect on the living body such as locally decreasing the pH. Therefore, an alkaline substance that absorbs PO 4 3 is required. The fourth calcium phosphate is C
When the a / P molar ratio is 2.0, Ca during conversion to apatite
2 + to release the absorbed PO 4 3 ~ a.
【0009】第4リン酸カルシウムの配合量が5重量%
未満の場合、遅延剤としての効果が発揮されず、25重
量%を超えると、初期の強度が低くなり過ぎるため使用
できない。また、α型第3リン酸カルシウムと第2リン
酸カルシウムとの配合量は、第4リン酸カルシウムの配
合量を考慮し決定すべきであるが、α型第3リン酸カル
シウムが90重量%を超えると硬化が遅くなり、また7
0重量%未満では強度が低い。一方、第2リン酸カルシ
ウムが10重量%を超えると強度が低くなり、また一方
5重量%未満では硬化が遅くなる。更にセメントを高強
度にする、すなわちセメントと硬化液との練和時の粉液
比を高くするには、主成分のα型第3リン酸カルシウム
の焼成温度を1400℃以上、1500℃未満とするこ
とが好ましい。1400℃未満では高強度化の効果が発
現しない場合があり、1500℃を超えるとα’型第3
リン酸カルシウムに転移して水和活性を減じる可能性が
あるので好ましくない。The content of quaternary calcium phosphate is 5% by weight.
If it is less than 25% by weight, the effect as a retarder is not exerted, and if it exceeds 25% by weight, the initial strength becomes too low to be used. Further, the blending amounts of the α-type tribasic calcium phosphate and the dibasic calcium phosphate should be determined in consideration of the blending amount of the fourth calcium phosphate, but when the α-type tribasic calcium phosphate exceeds 90% by weight, the curing becomes slow, Again 7
If it is less than 0% by weight, the strength is low. On the other hand, if the amount of dibasic calcium phosphate exceeds 10% by weight, the strength will be low, and if it is less than 5% by weight, the curing will be slow. In order to further increase the strength of the cement, that is, to increase the powder-liquid ratio when the cement and the hardening liquid are kneaded, the firing temperature of the main component α-type tricalcium phosphate should be 1400 ° C or higher and less than 1500 ° C. Is preferred. If it is less than 1400 ° C, the effect of strengthening may not be exhibited, and if it exceeds 1500 ° C, α'type third
It is not preferable because it may be transferred to calcium phosphate to reduce the hydration activity.
【0010】[0010]
【発明の効果】本発明の高強度リン酸カルシウムセメン
トは、練和時の粉液比を高くすることができるため高強
度であり、また長期劣化も防止できる。更にまた局所の
pH低下による生体毒性もない。The high-strength calcium phosphate cement of the present invention has a high strength because it can increase the powder-liquid ratio during kneading, and can also prevent long-term deterioration. Furthermore, there is no biotoxicity due to local pH drop.
【0011】[0011]
【実施例】以下本発明を実施例により更に詳細に説明す
るが、本発明はこれらに限定されるものではない。EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited thereto.
【0012】合成例1 α型第3リン酸カルシウムの合成 高純度水酸化カルシウム((株)カルシード社製)3モル
を水10リットルに懸濁させ、これにリン酸2モルを水
で希釈して40重量%水溶液としたものを徐々に撹拌滴
下終了後、1日放置(室温)し、乾燥機(ヤマト科学社
製、商品名「DV61型」)にて110℃、24時間乾
燥させた。この凝集塊を1400℃、3時間焼成した
(モトヤマ社製、商品名「スーパーバーン」)。最後に
擂潰機((株)石川工場社製、商品名「かくはん擂潰機た
て型20号」)で粉砕し88μmのふるいを通過させ
た。 Synthesis Example 1 Synthesis of α-type tricalcium phosphate 3 mol of high-purity calcium hydroxide (manufactured by Calceed Co., Ltd.) was suspended in 10 liters of water, and 2 mol of phosphoric acid was diluted with water to 40 After the completion of the dropwise addition of the aqueous solution of about 1% by weight with stirring, the mixture was allowed to stand for 1 day (room temperature) and dried at 110 ° C. for 24 hours with a dryer (Yamato Scientific Co., Ltd., trade name “DV61 type”). This aggregate was baked at 1400 ° C. for 3 hours (manufactured by Motoyama, trade name “Super Burn”). Finally, it was crushed with a crusher (manufactured by Ishikawa Factory Co., Ltd., trade name "Kakuran crusher Tate No. 20") and passed through a 88 μm sieve.
【0013】合成例2 第4リン酸カルシウムの合成 合成例1と同様にして合成したが、水酸化カルシウムを
4モル、リン酸を2モル用いた。乾燥した凝集塊を10
00℃で3時間仮焼し、取り出して粉砕後、更に140
0℃で3時間焼成した。最後に88μmのふるいを通過
させた。 Synthesis Example 2 Synthesis of quaternary calcium phosphate Synthesis was carried out in the same manner as in Synthesis Example 1, except that 4 mol of calcium hydroxide and 2 mol of phosphoric acid were used. 10 dried agglomerates
Calcination at 00 ℃ for 3 hours, take out and crush, then 140
It was calcined at 0 ° C. for 3 hours. Finally, it was passed through a 88 μm sieve.
【0014】[0014]
【実施例1〜4】合成例1及び2で合成したα型第3リ
ン酸カルシウムと、第4リン酸カルシウムと、第2リン
酸カルシウム2水和物(和光純薬工業社製特級)とを表
1に示す配合割合にて混合し、水を表1に示す粉液比と
なるよう加え、練和した。練和したセメントペーストの
流動性はすべて同じであった。Examples 1 to 4 Table 1 shows the α-type tribasic calcium phosphate synthesized in Synthesis Examples 1 and 2, the fourth calcium phosphate, and the second dibasic calcium phosphate dihydrate (special grade manufactured by Wako Pure Chemical Industries, Ltd.). The mixture was mixed at a ratio, water was added so that the powder-liquid ratio shown in Table 1 was obtained, and the mixture was kneaded. The fluidity of the kneaded cement pastes were all the same.
【0015】次に、JIS T 6602に準じて硬化
時間を測定し、硬化体(直径7mm¢、高さ14mm)を3
7℃の生理食塩水中に1,7,28日間浸漬後取出し、
濡れたままJIS R 1608に準じて圧縮強度を測
定した。試験機はインストロン社製万能試験機、商品名
「1125型」を用いた。結果を表1に示す。Next, the curing time was measured according to JIS T 6602, and the cured product (diameter 7 mm, height 14 mm)
After soaking in physiological saline at 7 ° C for 1,7,28 days, remove
The compressive strength was measured according to JIS R 1608 while wet. The testing machine used was a universal testing machine manufactured by Instron Co., Ltd. under the trade name "1125 type". The results are shown in Table 1.
【0016】[0016]
【表1】 [Table 1]
【0017】[0017]
【実施例5,6】合成例1及び2で合成したα型第3リ
ン酸カルシウムと、第4リン酸カルシウムと、第2リン
酸カルシウム2水和物(和光純薬工業社製特級)とを表
2に示す配合割合にて混合し、水を粉:液=100:4
0(重量比)の割合で練和した後、室温下で硬化、乾燥
させた。翌日粉砕して300μm以下とし、生理食塩水
50mlを入れた三角フラスコ中に5gずつ投入した。
その後三角フラスコにキャップをし、37℃、120時
間放置し、液のpHを測定した。結果を表2に示す。第
4リン酸カルシウムを添加したものは明らかにpHが高
く、PO4 3~が捕捉されていることを示唆している。[Examples 5 and 6] Table 2 shows the combination of α-type tricalcium phosphate synthesized in Synthesis Examples 1 and 2, quaternary calcium phosphate, and dicalcium phosphate dihydrate (special grade manufactured by Wako Pure Chemical Industries, Ltd.). Mix in a ratio of water and powder: liquid = 100: 4
After kneading at a ratio of 0 (weight ratio), the mixture was cured and dried at room temperature. The next day, it was pulverized to 300 μm or less, and 5 g each was put into an Erlenmeyer flask containing 50 ml of physiological saline.
Then, the Erlenmeyer flask was capped and left at 37 ° C. for 120 hours to measure the pH of the liquid. The results are shown in Table 2. The one to which quaternary calcium phosphate was added clearly had a high pH, suggesting that PO 4 3 was captured.
【0018】[0018]
【表2】 [Table 2]
【0019】[0019]
【比較例1〜4】実施例1で用いた粉体を表3に示す配
合割合にて混合し、実施例1〜4と比較した。結果を表
3に示す。[Comparative Examples 1 to 4] The powders used in Example 1 were mixed at the compounding ratio shown in Table 3 and compared with Examples 1 to 4. The results are shown in Table 3.
【0020】[0020]
【表3】 [Table 3]
【0021】[0021]
【比較例5】実施例5,6で用いた粉体を表4に示す配
合割合にて混合し、実施例5,6と比較した。結果を表
4に示す。Comparative Example 5 The powders used in Examples 5 and 6 were mixed at the compounding ratio shown in Table 4 and compared with Examples 5 and 6. The results are shown in Table 4.
【0022】[0022]
【表4】 [Table 4]
Claims (1)
量%と、第4リン酸カルシウム5〜25重量%と、第2
リン酸カルシウム5〜10重量%とからなる粉体を含む
高強度リン酸カルシウムセメント。1. α-type tribasic calcium phosphate 90-70% by weight, quaternary calcium phosphate 5-25% by weight, second
A high-strength calcium phosphate cement containing a powder consisting of 5 to 10% by weight of calcium phosphate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4328185A JP2776179B2 (en) | 1992-12-08 | 1992-12-08 | High strength calcium phosphate cement |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4328185A JP2776179B2 (en) | 1992-12-08 | 1992-12-08 | High strength calcium phosphate cement |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH06172007A true JPH06172007A (en) | 1994-06-21 |
JP2776179B2 JP2776179B2 (en) | 1998-07-16 |
Family
ID=18207421
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4328185A Expired - Fee Related JP2776179B2 (en) | 1992-12-08 | 1992-12-08 | High strength calcium phosphate cement |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2776179B2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002000565A1 (en) * | 2000-06-26 | 2002-01-03 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002006179A1 (en) * | 2000-07-19 | 2002-01-24 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002068358A1 (en) * | 2001-02-28 | 2002-09-06 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002068357A1 (en) * | 2001-02-28 | 2002-09-06 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002079112A1 (en) * | 2001-03-28 | 2002-10-10 | Mitsubishi Materials Corporation | Kneaded product containing calcium phosphate cement and method for preparation thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0244050A (en) * | 1988-08-01 | 1990-02-14 | Tokuyama Soda Co Ltd | Hydraulic pellet |
JPH02311340A (en) * | 1989-05-24 | 1990-12-26 | Sumitomo Cement Co Ltd | Hydraulic cement composition |
-
1992
- 1992-12-08 JP JP4328185A patent/JP2776179B2/en not_active Expired - Fee Related
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0244050A (en) * | 1988-08-01 | 1990-02-14 | Tokuyama Soda Co Ltd | Hydraulic pellet |
JPH02311340A (en) * | 1989-05-24 | 1990-12-26 | Sumitomo Cement Co Ltd | Hydraulic cement composition |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002000565A1 (en) * | 2000-06-26 | 2002-01-03 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002006179A1 (en) * | 2000-07-19 | 2002-01-24 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002068358A1 (en) * | 2001-02-28 | 2002-09-06 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002068357A1 (en) * | 2001-02-28 | 2002-09-06 | Mitsubishi Materials Corporation | Calcium phosphate cement |
WO2002079112A1 (en) * | 2001-03-28 | 2002-10-10 | Mitsubishi Materials Corporation | Kneaded product containing calcium phosphate cement and method for preparation thereof |
Also Published As
Publication number | Publication date |
---|---|
JP2776179B2 (en) | 1998-07-16 |
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