DE2130984A1 - Dental cement preparations - Google Patents

Description

concerning:

"Dental cement preparations" addition to DP 1 ° 4l 4-80

The invention relates to tooth cement preparations based on silicate tooth cement powders and one containing phosphoric acid Mixing liquid.

Silicate dental cements are generally made by mixing a phosphoric acid solution with Dental cement powders, which in turn come in the form of fine Silicate frits are made with the addition of aluminum and zinc to the acid solution before the addition the frit to adjust the setting time. A commonly used mixing liquid consists of one about 50% by volume o-phosphoric acid, containing aluminum

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and zinc as "modifiers" in proportions such that there are about 13 % free acid and about 35% mixed acidic phosphates of zinc and aluminum in solution. In general, the frit is a fluoroaluminium silicate glass containing sodium and calcium, which corresponds to the following empirical formula as a first approximation:

2Na.3Ca.3,5Al ₂ O ₅ .9 (SiO ₂ F) .O, 5P ₂ O ^.

A corresponding mixture of the constituents has a satisfactory setting time, the solidified material has a low solubility in water (0.7%), it is translucent and achieves a satisfactory strength in a permanently moist environment (after 24 h in water at 37 ^° C., ie Mouth temperature, is the compressive strength

> 14- kg / mm). Specifications for dental cements can be found in British Specification 3365 from 1969 and American Dental Association Specification No. 9 ·

It turned out, however, that dental fillings with cement only last about 3 to 7 years and one of the reasons for this is too can be seen that there is a lack of resistance to dilute acids occurring in the mouth, such as lactic acid, which is contained in saliva and formed by bacterial activity in dental plates will, citric acid from fruits and beverages,.

In the earlier application P 19 42 480.3 a mixing liquid is used proposed for the production of dental cements with better acid resistance. Then a Mixing the dental cement powder with a phosphoric acid solution containing physiologically harmless metal ions from the third group of the periodic table with an order

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number greater than 13 »so that one obtains a mass which is sufficient is long plastic in order to be able to shape it into the desired shape before hardening to dental cement.

It is known that such phosphoric acid solutions containing more than about 5 ¹ A of the physiologically harmless metal of the 3rd group of the periodic table have a tendency to precipitate crystals when standing for a long time, for example 6 months, and thereby deplete the metal ions mentioned in the phosphoric acid entry. This impoverishment leads to non-optimal properties of the dental fillings, which were produced using these ¹¹ old "solutions. For optimal acid resistance of the fillings, however, the largest possible amount of metal of the 3 · group should be present in the cement.

It has been found that these problems can be solved by using the metal or a corresponding metal compound from the third group of the periodic table is added to the cement powder and not so much to the mixing liquid. Find the Solution, however, within a short period of time, e.g. 6 months, can result in both the cement powder and the Mixing liquid are the metal from the third group of the periodic table, which is advantageous in some cases.

The invention thus relates to tooth cement preparations, in which in the silicate tooth cement powder and optionally also in the mixing liquid a metal or a metal compound of a physiologically harmless metal from the third group of the periodic table with an atomic number greater than 13 is included.

The grain size of the cement powder is a maximum of 50 μm, but preferably below ^ O /

The metals of the third group, which can be used according to the invention as a metal or in the form of its compound, can the rare earth metals are mentioned, but preference is given to gallium, indium and scandium, especially indium, which is one of the

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the most cements.

The dental cement powders as such are known ("Science of Dental Materials ", E.W. Skinner and R.W. Phillips, W.B. Saunders & Co., London, 6th Edition, 1967, chap. 30) · Im Generally, the alkaline earth metal of the silicates is calcium, but magnesium can also be included if desired. In addition, the silicate also contains an alkali metal such as potassium or especially sodium in combination with the phosphate and fluoride. Such silicate dental cement powders are commercially available.

The ingredients from which the cement powder is made include silica, alumina, calcium fluoride, sodium hexafluoroaluminate, and aluminum phosphate. It is It is possible to start with raw products in the manufacture of the cement powder that represent a combination of the above elements, e.g. sodium oxide, sodium fluoride, aluminum fluoride, Calcium oxide, calcium phosphate, sodium fluorophosphate.

In the dental cement powder used according to the invention, the proportion of SiCv is advantageously 35 "to 50, preferably 35" to 40, in particular 39 parts, the proportion of AIoO, 6 to 30, preferably 20 to 30, in particular 27 parts, the proportion of alkaline earth fluoride ( calculated as CaFp or the corresponding amounts of the other fluorides) 7 to 18, preferably 10 to 14, especially 12 parts and the proportion of alkali hexafluoroaluminate (expressed as Na ^ AlFg or the corresponding amounts of other hexafluoroaluminates) 5 "to 18, preferably 5" to 11 , in particular 6 parts and finally the proportion of AlPO ₂ , 0 to 10, preferably 4 to 1Θ, in particular 7 parts.

Unless otherwise stated, the here

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named parts and percentages in each case by parts by weight and% by weight. The aluminosilicate dental cement powders are im generally characterized by the constituents and not so much by the exact analysis. These digit values differ somewhat due to volatility from particular Siiy during the melting of the glass offset. Since the analysis of such glasses is difficult and expensive, aluminosilicates of this type are usually the proportions of the components are given.

Physiologically harmless metal of the third group of the periodic table can be present in a proportion between 0.5 and 15, preferably 5 to 15, in particular 7 to 11, especially about 9 % InoO, or the corresponding amounts of the other metal oxides from the third group of the periodic table . Under certain circumstances the percentage can go up to 20%.

The preparation can be produced by various methods. The following is to explain the invention primarily indium, but the other metals of the third group can be used in a similar manner Apply group of periodic table.

Dental cement powder based on aluminum silicates can be mixed with indium or an indium compound, e.g. Salt, mix so that there is a simple blend of the two ingredients. Can improve the mix the mixture is ground, the indium or the indium compound can be dissolved in an appropriate solvent and then apply the solution to the powdered aluminum silicates. A preferred method is to use indium or indium compound to be admixed with the molten aluminum silicate or the offset in order to obtain a homogeneous melt * in which indium is evenly distributed. That

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Indium can be used as a metal but preferably in the form apply a compound, e.g. a thermally decomposable compound, such as the carbonate or in particular the oxide or Hydroxide. It is often difficult to disperse and react the oxide or hydroxide in the glass melt cause, but this problem can be solved by melting at a temperature of 1480 to IV> 0 ° C with fine oxides or hydroxides with a particle size below 5 / um, as obtained e.g. by freeze-drying. The melting process is preferred because it is more uniform Dental cement is obtained after treatment with the phosphoric acid. This has a particular practical advantage since for aesthetic reasons the fillings as far as ... as any possibly resemble the surrounding tooth part. This is especially true of front teeth, which is why the Dental cement preparations according to the invention are particularly suitable.

The cement powders according to the invention are mixed with the phosphoric acid to thereby obtain the dental cements. The phosphoric acid can be o-phosphoric acid or a condensed phosphoric acid, such as pyrophosphoric acid. Commercially available ο-phosphoric acid contains small amounts of condensed phosphoric acids and is therefore very suitable for the purposes of the invention. Used as a starting product it is preferable to use a highly concentrated phosphoric acid, e.g. 88 wt. 50 wt .- ^ is diluted. The phosphoric acids can contain aluminum ions, as usual, for example up to 2 wt .- ^ Al. In In this case it is advisable to dissolve the aluminum in the concentrated acid and only then to dilute it.

As already mentioned, can., In the sense of the older proposal the phosphoric acid also physiologically harmless metal ions from the third group of the periodic table with a Contains atomic number greater than 13 «According to the invention, it contains both the cement powder and the mixing liquid

109853/18 97.

one or more of the metals of the third group, so you can in the dental cement preparation a total of more metals of the third group as if this were only present in one of the components. In general you can say that the acid resistance of the cement is higher the higher the proportion of Group III metal, e.g. Indium, is in it.

Finally, other substances such as fluoride, ethylene glycol or boron compounds can also be found in the solution. The metals of the third group present in the cement powder and in the mixing liquid can be the same or different indium is preferred in both cases. Indium can be found in phosphoric acid up to one concentration of 5 wt .-% are present.

The packaging of the dental cement preparation according to the invention happens as a two-part pack, wherein the cement powder according to the invention in the one part and the Phosphoric acid is present in the other part. When you mix the two you get a plastic mass that turns into dental fillings lets shape and hardens quickly. The mixing ratio of the two components is between 1.6 and 1.4 g, preferably 1.6 to 1.55 g cement powder to 0.4 · ecm Mixing liquid. A common pack contains two containers, one for the cement powder and another, in particular a bottle for the phosphoric acid. The relative proportions of powder to acid are generally between 14 parts by volume to 6 parts by volume, i.e. 14 g of powder to 6 ecm of liquid. At. Another embodiment is Ratio of the two components 1.6 to 1.4 g of powder to 0.4 ecm of liquid, the contents of the two pack parts is mixed, you get a plastic mass that can be processed immediately. The two parts of the pack are separated from one another by a membrane, for example, which

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can be more easily destroyed than the outer packaging material. Immediately before the membrane is destroyed, e.g. by squeezing the liquid part with the fingers, xx the contents of each part are carefully mixed and then the container is opened so that the plastic mass is ready for use is present.

The dental cements according to the invention are intended to To be prepared immediately before use, with the two components of the pack brought together, mixed and brought into the required form. The mixed components form a plastic mass, the you can pour, shape, blow or otherwise shape in the desired way, for a short period of time, in which the mixture retains its plastic properties.

The amount of phosphoric acid required for one serving of dental cement can be easily removed from the container with the help of a pipette or a dropper or the like. It is then mixed with the appropriate amount of cement powder mixed, the components mix quickly to form a homogeneous mass that cures within a few minutes starts and is usually completely hard within about 5 minutes of mixing. The curing speed, the firmness of the finished product etc. can be adjusted in part by the powder to liquid ratio. This should ideally be between 1.4 and 1.6 g powder and 0.4 ecm liquid. Too little or too much powder in a mixture often makes molding difficult, but it is it is not essential to adhere to these proportions. Careful matching of powder and liquid Components leads to a usable plastic mass, which hardens in a corresponding time. Often too good The resulting powder to liquid ratio is 1.5 g to 0.4 ecm, but it can sometimes be stiffer

xx or piercing with one provided inside - 9 Needle,

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Mixtures with a ratio of 1.6 g. 0.4- ecm preferred.

With the help of the preparations according to the invention, dental cements are easily obtained which meet the requirements of the British Specification $ 6 $ with regard to compressive strength, curing time, transparency, solubility and arsenic content.

It can be assumed that the dental cements have a structure containing glass particles which have reacted on the surface and are bound in a matrix of high molecular weight indium (or another metal of the third group) -aluminophosphate silicates bridged by calcium. The investigations with an electron probe on a cement from an indium-containing aluminosilicate and 50 $ phosphoric acid show that the concentration of indium in the matrix 50 ° / o was in the glass and that the indium is present uniformly distributed in the matrix. The dental cement is preferably not entirely white and consequently the physiologically non-precious metal of the third group in the cement is preferably in the trivalent state. In the following, the preferred production method for cement powder according to the invention is explained in more detail using indium-containing cements by the melting process.

The mixture for the cement powder is mixed in a cone mill made of porcelain with porcelain balls for about 1 hour. The indium is preferably used as indium oxide having a particle size of less than 5 / ^u m. The mixture is then poured into a sillimanite crucible with a platinum inner surface and a platinum lid. With large approaches you can too

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work with a Sillimanit crucible, but the proportions of aluminum oxide or silicon dioxide leached from the crucible material must be taken into account when moving. The mixture is heated in the crucible allmählichf ζ · Β ₀ in an oven, in 4 hours to about 1Λ50 G and about 2 maintained at this temperature. Samples are taken from time to time and these are checked for clarity after quenching. During the reaction, the powder mixture changes into a glass flow. The reaction is ended when a sample is clear or only slightly translucent after quenching crucible is then removed from the oven and the heating completed, the flow of glass on a smooth heat-conducting surface bonded, does not adhere to v / hich it, for example. When the glass has solidified into a thick cup korrosionsbestündigem steel, di around 1 The glass frit obtained in this way is washed, dried, ground up and then sieved, for example through a nylon fabric, vial size about 60 μm.

If the hardening time of the cement from the mixture of the sieved frit with the phosphoric acid is undesirably long, the sieved frit can be ground up further and sieved again. The hardening should generally take place in 3 to 8 minutes, preferably in 4.5 minutes, at 37 ^° C. (BS 3365; Separate the finer ones, after which the coarser Korrj is dried.

Is the hardening time appropriate, but the consistency and flow resistance ^? the preferred ratio of powder to liquid of 1.6 g O ₁ ^ f ecm insufficient, it may be the sieved frit in boiling v / ater, Zbl to 2 h, heat up prior to drying and repeated examiner. The consistency or fluidity of the mixture - 11 -

10 9 8 5 3/1897

is better then; if the hardening time rises above the desired value, you can still use the sieved powder a little grind.

The invention is further illustrated by the following examples. Unless otherwise stated, the cement powders have been produced in the above manner. The corrosion regulations the cements were made in accordance with British Specification 33ό5ι

by using cylindrical test specimens for. the compressive strength according to the examples 1 and 2 and disk-shaped for the determination of the solubility according to the remaining examples " immersed in the special acids for the specified times at a temperature below 37 C (body temperature) became. After each time interval, the test specimens were removed, cleaned in water with the aid of ultrasound, stored in a closed vessel at 100% relative humidity and room temperature, then removed from the container and weighed. The results are directly comparable and the weight losses are additive.

For s ρ ie 1 1

Glass offset for the cement powder -

Gew.-S

SiO 2 Al ₂ ° 3 Approx AlPO ^

43.2 14.5 12.4

6.2

₅₆ '13.5

In (OH) ₅ (freeze dried) 10.2

The components of the batch were melted into a clear melt, which was then poured into water,

the melt temperature was 1470 ⁰ C. The quenched Pritte

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was a clear glass with a pale yellowish tone. The X-ray analysis gave no evidence of crystalline residues. The indium content, based on metal, was 6.3% by weight.

The quenched Pritte was ground to a size below 40 μm and then mixed with (a) a commercially available phosphoric acid containing 50 % o-phosphoric acid and aluminum and zinc, so that 13% free acid and 35 %, were used to produce the dental cements % mixed zinc and aluminum phosphates are present, and (b) an indium-containing phosphoric acid according to the older proposal, containing 5.65% by weight In ⁵⁺ , 1.40% by weight Al ⁵⁺ , 29.42% by weight bound phosphates (H ₂ PO ₄ O, 16.28% by weight of free phosphates (H ₃ PO ₄ ), 1.48% by weight of H ₂ F ₂ , 44.77% by weight of water, Ί, ΟΟ% by weight .-% ethylene glycol.

The dental cement obtained from the mixing liquid (a) Required a curing time of 3.5 minutes, achieved a compressive strength of 14.8 kg / mm and had water solubility of 0.8% by weight. The powder to liquid ratio was 4 g / ccm.

The superior properties of the ^! Tooth fillings are shown in Table I on the basis of the loss in% by weight.

T. TABLE E I

ground indium comparison

containing frit + hü. Frit +

H ^ PO ₄ - Solu tion H ₅ PO ₄ solution

without indium with indium

Lactic acid pH3

after 24 hours 2.5 2.0 '11.2

after a further 72 hours 4.7 3.9 18.0

(buffered, 0.1 n)

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Example 2

Offset for the fry analysis • SiO ₂ the frit Wt% OaO Wt% SiO ₂ 45.8 .Al ₂ O ₃ 40.6. CaF ₂ 13.2 In ₂ O 8.7. AlPO ^ • 6.6 F ¹ 30.2 Na ₃ AlF ₆ 14.6 PO ₄ ¹ '' 5.8 Na ₂ O 6.3 Δ ι Ij 8.8 4.3 In (OH), 11.0 4.8 (freeze-dried net)

The melting temperature was about 1450 ° 0, the quenched frit was a clear glass. The X-ray analysis could not Provide evidence of residual crystallinity.

The quenched frit was reduced to a grain size <40 , van. on ground and the commercially available mixing liquid of Example 1 applied. Curing time 4 min, compressive strength of the cement 19 kg / mm ² , water solubility 0.65% by weight, powder to liquid ratio 4 g / ccm.

Table II shows the superiority of the tooth fillings according to the invention based on the weight loss.

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TABLE II

according to the invention Fries + EUPO ^ solution

Lactic acid pH3 after 24 h 3.0 ¹¹ "after further

96 h 4.4

"π. · 5 days 7.5 ' 0.2 η-acetic acid after a total of

24 hours

1.0

xx buffered, 0.1 η
Examples

Comparison hü. Frit + H, P0 ₄ solution

10.2

23.0 30.9

3.2

3 to 51

In the following table III the offset for the frit is the melting temperature and the melting time are given. All products were clear, only the products according to example 5, 21, 45, 46 were opaque and the products of Examples 22, 48 and 51 were translucent.

TABLE III:

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TABLE III

at
game SiO ₂ ^Α1 2 ° 3 CaF ₂ ^Ιη 2 ° 3 Nft, AlF ₆ ^Α1Ρ0 4 ι ι I
ι. at this' Appearance 3 43.2 l4.4 12.3 10.3 13.6 6.2 Melting temp.
⁰ C Temp, h " clear 4th 45.8 8.8 13.2 11.0 14.6 6.6 1450 V Il 5 43.2 14.4 12.3 10.3 13.6 6.2 1470 2 opaque 6th 43.2 14.4 12.3 10.3 13.6 6.2 1475 2 clear ο 7th 46 ₁ 0 11.0 13.0 8.0 15.0 7.0 ' 1450 2 It 00
cn 8th 49.0 9.0 13.0 7.0 15.0 7, ° 1450 2 Il co ? 46.0 10.0 ί3, ο 8.0 17.0 6.0 ' 1420 2 'Il 00 10 45.8 8.8 13.2 11.0 14.6 6.6 ' 1450 2> 5 Il 11th 42.0 15.0 12.0 10.0 14.0 7.0 1450 3 . η 12th 40.0 15.0 16.0 10.0 12.0 7.0 - 1450 2-, ε η 13th 40.0 17.0 14.0 11.0 11.0 7.0 1450 1 Il 14th 38.0 15.0 17.0 1OyO 13.0 7.0 ' 1450 Vis It 15th 39.0 16.0 15.0 10.0 13.0 7.0 · 1450 1.5 η 16 ■ 39.0 19.0 12.0 11.0 14.0 5.0 1450 3.5 η 17th 40.0 19.0 13.0 10.0 12 ₇ Ο 6.0 1450 2 η 1450 2

CXl 00

-Λ

σ »

Continued TABLE III:

Forts, too

TABLE L E III

CD CO OO

at
game SiO ₂ ^A1 2 ° 3 CaF ₂ ^In 2 ° 3 Na ₅ AlF ₆ AlPO ₄ Schm € lz- "~ ^o _c
temp., at this
' Temp. Appearance 18th 42.0 19.0 11.0 10.0 12.0 6.0 1450 2.5 clear 19th 42.0 20.0 lOjO lOjO 12.0 6.0 145O 2 "ti 20th 42.2 18.7 11.7 9.2 12.6 5, ⁶ 1475 1 Il 21 36.8 21.2 11.8 10.7 13.6 5.9 1450 3 * 5 opaque 22nd 36.6 23.5 11.5 10.8 10.8 6.8 1460 ² p see through ending 23 38.0 23.0 12.0 11.0 9.0 7.0 1450 clear 24 38.0 23.0 13.0 11.0 8.0 7.0 1450 '2 - Il 25th 38.0 22jO 14.0 11.0 8jO 1450 Il 26th 36.0 24.0 14.0 11.0 8.0 7.0 1450 Il 27 37.0 25.0 13.0 10.0 8.0 7.0 1450 1 Il 28 37.0 26jO 13.0 9.0 8.0 7.0 1450 2 * 5 ^: ti 29 42.0 24.0 11.0 9.0 ?, 0 5.0 1450 Il 30th 40.0 25.0 12.0 9.0 9.0 5.0 1450 1 Il 31 39.0 25.0 12.0 9.0 6.0 1450 2 Il 32
I. 39.0 24 ^ 0 12.0 9.0 10 ^ 0 ⁶ i0_ 1450; ι-, αδ Il

GO CD CD 00

Ports. TABLE III:

Ports, too! TABLE. III

at
game ^sicr 2 ^A1 2 ° 3 CaF ₂ ^In 2 ° 3 Na ₃ AlF ₆ AlPO ₄ Enamel q
temp. ' ^c At this
Temp. '
H Appearance 33 39.0 23.0 12.5 9.0 6.0 1450 2 clear 34 38.0 23.0 12.0 9.0 11.0 7.0 1450 2 Il ο
to 35 37.5 25.5 13.0 9.0 8.0 7.0 1450 2 Il 00 36 38jO 25.0 13j0 9.0 8.0 7.0 1450 It to 37 4θ.Ο 24.0 12.0 9.0 8.0 7.0 1450 0.5 " Il co 38 41.0 24.0 12jO 9.0 7.0 7.0 1450 O ₁ S : Il 39 39.0 25.0- 13 _f 0 9.0 7.0 7.0 1430 0, Z5 It 40 41.0 25.0 11.0 9 _; P. 7.0 7.0 1450 1 It 41 38jO 24.0 14.0 9.0 8.0 7.0 1450 ty it 42 38.0 23jO 15.0 9.0 8.0 7.0 1450 Il 43 - 40.0 23.0 14.0 9.0 7.0 · 7.0 1430 US Il 44 • 41.0 26.0 10.0 9.0 7.0- 7.0 1450 I ₄ p Il 45 40.0 27.0 9.0 9.0 8.0 7.0 1450 2 opaque 46
ι 39.0 23.0 12.5 9.0 10.5 6.0 1450 2.5 It

GO CD CO 00

CO

Forts ^TA BELLE:

Forts, to - TA BELLE III

CD CO CD CJl approx

oo to

At- ^:
game ^S i ° 2 ^A1 2 ° 3 CaF ₂ " ^ln 2 ° 3 Na ₃ AlF ₆ AlPO ₄ Melting temp. _O
· »C At di es'eü »'tfemp.
H Appearance 47 4l, 0 25 _f 0 11.0 9.0 7.0 7.0 1450 1 clear 48 39.0 27.0 12jO 9.0 6.0 7.0 1450 2 translucent 49 42.0 24.5 12.5 9.0 6.0 6.0 1450 clear 50 39.0 24.0 13.0 9.0 9.0 6jO 1440 . 0.75 Il 51 39.5 26.0 12 ₇ 5 9.0 S ⁰ 7.0 1440 •
2
• translucent

oo

I -Λ

OJ CD CD OO

The offsets for example = 3 to 18 were in one Sillimanit crucible and for examples 19 "to 51 in one Platinum crucible melted down.

• ·

The product of Example 48 is the best because it is the highest Strength is achieved.

The product of Example 48 contained 38.23 fo SiO ₂ , 31.91 fo Al ₂ O ₃ , 8.95 fo CaO, 91 28 fo In ₃ O ₃ , 3.53 # Na ₃ O, 3i88 f ₀ P ₂ O ₅ , 7 , 12 fo F, so a total of 102.9 f ° · Some of these elements are not completely present as oxides but can also be present as fluorides. For this reason the sum of the contents exceeds 100 .fo.

The product of Example 48 was made with an indium-containing. Phosphoric acid according to Example 1 mixed. The cement had the following properties: hardening time 4.5 min, water solubility 0.6 fo, average compressive strength 22.5 kg / mm. The results of the corrosion tests are summarized in Table 4. The lactic and citric acids are 0.1 η in terms of the anion

nenkonzentration and were adjusted to the specified pH values by adding sodium hydroxide. The acetic acid was 0.2 η and not buffered. So it had a pH of 3.5.

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Lactic acid pH 3 Tabel
according to Zk k
H Indium cement
Gevr, -fo
2.8 hü.Silicate cement
Gev /.-'/ ό
18.9 Il Il k8 H 5.9 36.3 Il It 120 H 8.9 56.6 It pH k according to Zk H 2.0 10.2 Il Il k8 H 4.0 21.0 Il Il 120 H 6.3 35.0 Il pH 5 Zk H 2.0 6.9 Il Il k8 H 3.5 13.6 Il Il 120 H 5.8 22.0 acetic acid 0.2 η according to Zk H 0.6 2.3 It Il k8 H 1.2 k, 6 citric acid pH5, 5 after Zk h 9.6 17.8 Il Il kt 15.7 32.7 5 h

Example 52

A scandiumhaltiges dental cement powder was prepared by melting a mixture of 39 ^L / ° siop, 27 / S Al ₂ O 11 ^c / o CaP _2, 6 ^c / o Sc ₂ Oo ₁ 8 tf Na ₃ AlP _6, 9/0 AlPO ^ ₅ Melting temperature 1450 ° C, melting time 2 h. It was quenched, milled and sieved to a grain size below 60 μm. The product was translucent.

The cement obtained with commercially available phosphoric acids from Example 1 had a hardening time of 3.5 minutes.

Claims

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Claims (3)

Claims 1. Modification of the tooth cement preparation according to DP ... (registration P 19 41 480.3) from a silicate tooth cement powder and a mixing liquid containing phosphoric acid, characterized in that the physiologically harmless metal of III. Group of Periodic table with an atomic number-> 13 or its phosphoric acid-soluble compound wholly or partially in the tooth cement powder. 2. Dental cement preparation according to claim 1, characterized in that the cement powder is a Glass frit made of SiO ₉ , Na ₃ AlP ₆ and AlPO. is, in which the metal or metal compound is located. 3. Tooth cement preparation according to claim 2, characterized in that the Gä | lsf ritte 39 $> 27 $> Al ₂ O ₃ , 12 g CaP ₂ , 6 i> Na ₃ AlP ₆ , 7 $> AlPO ₄ and 9 % contains. 8192 109853/1897