DE2626092A1 - BINDING AGENT COMPOSITION FOR TEETH REPLACEMENT - Google Patents

Description

The invention relates to a binder composition for dentures.

Dentures generally have a metal core or a metal framework, with the porcelain on the visible Surface is arrested for aesthetic reasons. For many years, gold has been used in the production of the Metal core or metal frame used. However, because of the high price of gold, many attempts have been made It has been undertaken to use base metal alloys instead of gold (see, for example, U.S. Patents 1,736,053; 2,089,587; 2,156,757; 2,134,423; 2,162,252; 2,631,095; 3,121,629; 3,464,817; 3,544,315; 3,685,115; 3,716,418; 3,761,728 and 3,834,024, as well as the standard U.S. dental literature such as Skinner and Phillips, "THE SCIENCE OF DENTAL MATERIALS, "p. 582, 6th Edition, W.B. Saunders Company,

609853/0959 -2-

Philadelphia and London, 1967 and Morrey and Nelson, "DENTAL SCIENCES HANDBOOK," page 168, American Dental Association and National Institute of Dental Research, U.S. Government Printing Office, Washington, D.C., 1970). Suitable alloys are generally nickel or cobalt alloys, in particular nickel-chromium alloys.

If such non-precious metal alloys are used for a framework or a core that is to be veneered with porcelain is to be used, the porcelain is generally burned directly onto the metal surface and on this held in place by mechanical adhesion. A roughening of the metal surface is necessary to create mechanical adhesion necessary. Proper roughening for mechanical adhesion is extremely difficult. In addition, the mechanical one is sufficient Adhesion is often not sufficient to withstand the stresses and strains of daily use, so that the porcelain can peel off can occur in whole or in part from the metal framework.

It is therefore the object of the invention to enable peelable adhesion.

The invention relates to binders and more particularly to compositions and methods of joining dental porcelain to a base metal alloy framework. When dental porcelain is connected to the metal framework using the binders according to the invention, a firm bond generated that withstands peeling of the porcelain under much higher loads than without a binder. Furthermore, the Components free from materials that can cause tissue necrosis or toxicity problems.

The binder according to the invention is characterized by: (1) a metal-porcelain. Binding, forming component of aluminum powder in admixture with glass powder, which is at a temperature in the range from approx. 950 to 1010 ⁰ C (1750 ° to

-2-

609853/0959

1850 ^° F), preferably at approx. 980 ^° C (1800 ^° F), with (2) a carrier component. -Melts which can generate a reducing atmosphere during the firing or sintering of the binder. The glass used here is a mixture of non-crystalline oxides, as they are basically known per se and are also described in more detail. The carrier can be an inert carrier which only has a carrier function, in which case the reducing atmosphere required for sintering or firing the binder is generated by separately supplied reducing gases; however, according to the preferred embodiment of the invention, the reducing atmosphere is provided by the carrier component itself. “Binder composition” is understood here to mean both the adhesion-forming component and the carrier component. The terms "adhesion-forming component" and "adhesion-forming agent" relate to the aluminum-glass mixture. The terms "core", "framework", "substrate" and "structure" have the same meaning in connection with "metal" and refer to the dental construction to be veneered with porcelain.

In a preferred exemplary embodiment of the invention, the adhesion-forming component is a mixture of aluminum and glass which ^{melts in the range from 975 to 990 °} C. (1790 to 1810 ^° F). The aluminum is in the form of a powder that passes through a sieve with sieve number 400 (corresponding to a mesh size of 0.0038 mm) and is preferably in the form of a powder with a particle size of 20 μm. The glass is a mixture of non-crystalline oxides which include silicon dioxide, aluminum oxide, sodium oxide, calcium oxide and magnesium oxide; it may contain one or more of the following oxides: tin dioxide, potassium oxide, lithium oxide, boron oxide, titanium oxide, barium oxide, zirconium oxide, etc. The amounts of the first named oxides,

6098 5 3/0959

which can be described as the essential ' * can vary considerably depending on the occurrence and / or amount of the latter or non-essential oxides;,: The essential oxides can be present in the following amounts (all data in% by weight): approx. 47 to 74 % Silica, 1 to 16% alumina, 3 to 17% sodium oxide, 0.6 to 6% calcium oxide, and 0.4 to 4% magnesium oxide. The other oxides can be present in the following amounts: 0 to 12% potassium oxide, 0 to 25% tin dioxide, 0 to 5% lithium oxide, 0 to 2% boron oxide and 0 to 2% barium oxide. The preferred composition. of the glass results when the oxide composition is within the following ranges, expressed in weight percent: 47 to 63 percent silica; 9 to 25% tin dioxide, 10 to 14% alumina; 8.5 to 10% potassium oxide; 3 to 5% sodium oxide; 0.6 to 1 _; 3% calcium oxide; 0.4 to 0.8% magnesium oxide, 0 to 5% lithium oxide. Many suitable types of glass are commercially available as glass, porcelain, ceramic oxides, etc. Other glass compositions can be prepared by dry blending the corresponding oxides in appropriate amounts, sintering the mixture into a frit, quenching it with water, drying it and turning it into a Ball mill is ground to the appropriate degree of fineness, as - it is known. The glass compositions are powders with a particle size that can pass through a sieve with the sieve number 165 (approx. 60 / in), or even finer. The particle size of both the aluminum and the glass compositions are limited below by the finest powders currently available. Should finer powders become available, these would be preferred.

The carrier component of the binder composition according to the invention is formed by liquid organosilicon compounds such as silicone oil, silane, etc. Suitable liquid organosilicon compounds are those

609853/0959

which, after the addition of the binder component powder, remain suitable for spreading. Preferred silicon organic liquids have a viscosity of about 4 to 40 cSt at 25 ⁰ C or 6 to 17 cSt at 37.8 ⁰ C (100 ⁰ F) or 45 to 85 Saybolt seconds. Apart from a suitable fluidity, these organosilicon compounds also generate a reducing atmosphere,

In compositions comprising a powdered mixture of aluminum and a glass in a liquid organosilicon compound, the precise amount of liquid carrier to be used with the powder mixture is not critical. In general, such amounts of the liquid organosilicon compound are used which ensure a suitable fluidity for brushing onto metal surfaces η _% . ·> With the use of liquids having a viscosity in the range 6 to 17 cSt at 37.8 ⁰ C (100 ⁰ F), the compositions with suitable.]! On coating properties are produced by using 0.25 to 0.75 parts by volume of liquid for each part by weight of solid mixture with an adhesion-forming component. Usually the solids content of the composition is about 60 to 80 percent by weight.

The proportion of aluminum and glass is

important. The aluminum component can make up approx. 40 to approx. 70% of the total solid mixture, with the remainder is formed by the glass component. Good results will be with a 50:50 mixture of aluminum and glass obtain.

The binder composition can be prepared by adding the adhesive component and the carrier component be mixed well somehow to achieve a substantially uniform pulpy composition.

-6-

609853 / 09B9 originally inspected

Preferably the solids, i.e. the aluminum and the glass powder, mixed together beforehand, and this one Powder mixture is mixed well with the liquid organosilicon compound. The preparation of the composition by admixing can be done immediately prior to use, or the powder mixture and liquid can be premixed become, i.e. the slurry composition can be prepared in advance. The composition can then of Dental technicians using conventional techniques.

The invention also relates to the use of the binder composition according to the invention to make dental porcelain to be securely connected with a metal core · A preferred embodiment provides for the use of the inventive Binder composition as an admixture to a carrier component, which creates a reducing atmosphere. However, the invention also includes the use of other agents for producing a reducing or non-oxidizing agent inert atmosphere, i.e. the carrier component can simply be an inert liquid with suitable fluidity.

According to the method according to the invention for connecting dental porcelain to a metal core or framework the binder composition according to the invention evenly on the corresponding surface of the metal core applied, which is prepared in a conventional manner, e.g. using wax ("lost wax" technique)

and has been thoroughly cleaned, for example, after which the coated metal core in air at a temperature of about 650-1050 ⁰ C is sintered (1200-1900 ⁰ F) in a dental porcelain furnace with dilute acid and / or sand paper. The coated and fired metal core is removed from the furnace, allowed to cool and then cleaned by brushing off loose material and

609853 / 09B9

Ultrasonic washes with warm water and then dried. The porcelain is then applied, and the resulting porcelain-coated metal core or the framework fired in a conventional manner.

To perform the first of the above steps, the binder composition is suitably applied. In general, it is convenient to use a brush. Good results are obtained regardless of whether the coating is thick, thin or medium thickness. It is essential, however, that all surface sections are uniform be coated with the binder composition.

In carrying out the sintering, the precise temperature and time of the heating can be varied. In an expedient for dental technicians procedure, the coated metal core is inserted into a furnace which is preheated to 650 ⁰ C (1200 ⁰ F), and quickly in air to a maximum temperature of about 980 to about 1050 C (1800 to 1900 ⁰ F) at a heating rate of about 32 to 38 ⁰ C (90 to 100 ° F / min). Preferably, the maximum temperature is in the range of about 1004-1016 ° C (1840-1860 ⁰ F). The total heating time when heating is carried out in this manner is less than 15 minutes.Alternatively, heating can be carried out at a lower temperature for a longer time.

If the sintering is to be carried out in a non-oxidizing (reducing or inert) atmosphere, the is generated by a source different from the carrier component, the furnace is equipped with a reducing or inert gas such as hydrogen, nitrogen, methane, carbon monoxide, Argon etc. filled during heating. The coated metal core is heated as described above.

-8th-

609853/0959

Cleaning the surface of the coated metal

after the binder has been sintered on is also critical

and essential for good adhesion of the Bprzellans am

Metal. If the cleaning stage is "omitted", cracks in the porcelain on. Cleaning with a brush and then ultrasound using water is probably the best Results, although other methods of removing non-adherent materials can be used.

The porcelain is applied to the binder-coated metal surface in any suitable manner otherwise used for coating metal surfaces in the absence of binder. It is preferably painted on with a brush or coated with a spatula. After <3rd application of the porcelain, it is georannt at temperatures that are suitable for the particular porcelain and the metal used. This firing can be done at any suitable temperature within the broad limits of about 850 to about 1100 ^° C (1600 to 2000 ^° F). Additional porcelain coatings can then be applied and fired in the usual way in order to complete the manufacture of the dental prosthesis / whereby an adhesion between the metal and the porcelain is achieved which is resistant to detachment when mechanical stresses are exerted.

The binder compositions of the invention can be used with metal alloys and porcelains that are used for a common ^ use if there is no binding agent are.

Metal alloys for which the binder compositions according to the invention are particularly useful are nickel and cobalt alloys, especially the nickel-chromium alloys. Typical alloys of this type are in the introduction

-9-

609853/0959

refer to literature (US patents and technical literature) on base metal alloys mentioned ^ Others Alloys with which the binder composition can be used are commercially available among various Trade names available..Other. Alloys with which Binder compositions useful are the subject of patent application P 26 03 860.8 of February 2 1976.

The porcelain that bond with the dental alloy.

is, can be, any _ .. porcelain, '.

Which is suitable for use with the selected alloy. "Porcelain" is understood here as dental porcelain, as it is known, which also includes Dentalg3Lasarteji. These generally include silica, alumina, potassium oxide, sodium oxide and minor amounts of other oxides. Usually the porcelain coating first applied to the metal is an opaque porcelain. A Opaque porcelain is designed to prevent the metal from passing through the final coating as much as possible can be seen. Opaque porcelains are commercially available and have an oxide composition either zirconium oxide, tin oxide, titanium oxide or zirconium silicate as an opacifying agent. The opaque one Porcelain usually comes with a relatively thick layer or layers of body or base porcelain coated, on which usually a final layer or coating on the tips of incisal porcelain follows. The basic porcelain is commercially available as gingival or basic porcelain (sometimes called dentin) and can be a small amount, an opaque one Means, while incis-al porcelain usually have one has a similar composition to the basic porcelain without an opacifying agent. With all coatings after the first coating, porcelain becomes porcelain with porcelain

609853/095 9

- ίο -

connected - During the first coating, porcelain is connected to metal, which is why the Binder composition problems to be solved occur when bonding porcelain to metal. The subject of the invention is therefore solely the joining of porcelain with metal. Since at present porcelain, that is connected to metal, is understood in the professional world as opaque porcelain, are the porcelains, those with metal by the binder composition according to the invention to be arrested are generally, but not limited to, opaque porcelains.

Porcelains with advantageous /. Liability are feldspar porcelains ^ they are'im. Oxide content similar to the glass component of the present binder. Typical porcelain compositions can be found in standard literature such as Skinner and Phillips, "THE SCIENCE OF DENTAL MATERIALS," page 518, WB Saunders Company, Philadelphia and London 1967; the compositions of various commercial porcelains are given on page 60 of Jean-Marc Meyer, "Contributions a I ¹ Etude de la Liaison Ceramo-metallique des Porcelaines cuites sur Alliages en Prosthese Dentair,", doctoral thesis, University of Geneva, 1971. Suitable porcelains are also the compositions which are described in US Pat. No. 3,052,982 and have the following oxide content: 61-67.8% SiO ₂ ; 11.7-17.1% Al ₂ O ₃ ; 0.1-2.6% CaO; 0.1-1.8% MgO; 2.37-9.6% Na ₃ O and 6.7-19.3% K "0. This composition can be changed to include lithium oxide in amounts. up to: 5% and / or an opacifying agent in amounts of about 0.05 to about 25% in addition, the other oxides being reduced or modified in their content. Suitable opaque porcelains can have the oxides in the following approximate ranges: Si ⁰ ? ^ ~ ^%; ^A lo ° ^ ^ ⁰ ~ 14%; CaO 0.6-1.3%; K ₃ O 8.5-11%; Na ₃ O 1.5-5%; MgO 0.4-

0.8% and SnO ₃ 9-25%. The invention is not restricted to a specific chemical composition of the porcelain;

609853/0 9 59

all commercially available dental porcelains or specially prepared porcelain compositions can therefore be used. Examples of commercially available porcelain are: opaque porcelain CERAMCO, gingival porcelain CERAMCO ^, opaque porcelain BIOBOND ** base or body porcelain BIOBOND * *, porcelain VITÄ ^ * ^x etc. (* trademarks of Johnson & Johnson or affiliated companies; '^ product of Dentsply International, Ine., York, Pennsylvania; ** "# Product of the company Vita Zahnfabrik, Säckingen, Germany). The selection of porcelain with regard to its exact composition depends to a greater extent on the metal alloy substrate to be veneered with the porcelain, In order for the binder to have the advantageous properties envisaged by the invention, the selection of the porcelain should be appropriate to the metal alloy core or substrate used. For example, the coefficient of thermal expansion of the porcelain should be comparable to or appropriately adapted to those of the alloy that a meaningful single thermal expansion c oeffJLzient can not be achieved for porcelain in contrast to metals in a wide temperature range of about 25 ° to 600 ⁰ C, which means that thermal expansion coefficients are valid only for a narrow temperature range. Therefore, after an initial determination of the coefficient of thermal expansion, empirical methods are often used to select the porcelain to be used with the respective alloy. The method of selecting the porcelain for use with a particular alloy does not form part of the invention, but when the porcelain and the metal alloy to be bonded are properly matched, the adhesive properties are significantly improved by using the binder of the invention. This means that even porcelain-metal bonds that have hitherto been regarded as having good adhesion are, in view of the results achieved with the invention, as very unsuitable.

-12-

609853/0959

enough to look at.

The by the binder compositions according to the invention The considerably improved adhesive strength achieved can be demonstrated qualitatively and quantitatively. if E.g. a mechanical load such as a hammer blow acts on crowns or test discs that are covered with porcelain If a binder according to the invention are veneered, detachment or separation occurs at the porcelain-metal interface practically hardly or not at all, while without using a binder the porcelain itself clearly detached from the metal.

Adhesion to the interface can also be demonstrated by making a slit in the porcelain surface is cut or sawed, a flat bar or knife blade is inserted into the slot and a rotating force is exercised. The crowns or disks produced without the use of a binder become complete or separated almost completely at the porcelain-metal interface while exerting this unusual force the crowns produced using the binder according to the invention remain securely adhered to one another. It can therefore be seen that the porcelain-metal adhesion is not impaired even under extraordinary loads remains and a break or breaks for it occur in the porcelain itself.

The adhesive strength can also be proven quantitatively. However, the respective values may vary from the specific Alloy-porcelain combination, from the method of determining the adhesive strength or from the treatment of the Hang off metal surface before arresting. So when the bond strength is measured as the force required to separate a metal rod is measured from a porcelain disc, which is attached to the rod around its entire circumference,

-13-

609853/0959

the measured values are higher than if the adhesive strength as Force is measured, which is required to separate porcelain bonds between the end faces of two rods. Also are the porcelain-to-metal bond strength values. generally higher when the porcelain is sandblasted Surface is applied as if it were on a polished or untreated surface is applied. Regardless of the assigned measured values, however, it has been found that for a special Combination of alloy and porcelain the adhesive strength is surprisingly high when binder compositions according to the invention be used.

The advantages achieved with the binder composition according to the invention appear to be due to the fact that the binder provides an adhesion-forming component in elemental and oxidized form at the correct time at the interface. The provision of a reducing atmosphere ensures that the adhesion-forming component is initially present in an elemental form. With continued heating, a reaction is likely to take place a desired portion of the adhesion component in an oxidized form, which then reacts with the porcelain during the porcelain firing _s tage. '

.- However, if the heating is too long or over 1065 ° C (195O ° F) takes place, the bond strength is reduced if the porcelain is subsequently applied and is burned. The invention is of course not bound to any explanation of the mechanism of action. Regardless of all possible explanations of the processes at the interface, it should be noted that an improved Adhesion is achieved by using the binder composition according to the invention.

The invention therefore provides a binding agent composition for dentures .for the connection of porcelain with a metal core or framework, in particular made of Michteisenmetallegierungen.an.

-14-

609853/0959

This binder composition has: (a) an adhesion-forming component with a powder mixture of aluminum and a glass which ^{melts at a temperature in the range from approx. 950 °} C. to approx. 1010 ^° C. (1750 to 1850 ^° F), and (b) a liquid carrier. The support can preferably generate up to about 1050 ⁰ C (1200-1900 ⁰ F) a Redukitonsatmosphäre at temperatures in the range from about the 650th The binder composition is applied to a metal core which is to blind with porcelain, and of about 650 ° C (1200 ⁰ F) to a temperature in the range of about 950 ⁰ C to 1050 ⁰ C (1750 to 1900 ⁰ F ) heated so. that a very strong adhesion to the interface. is generated, which is resistant to peeling of the porcelain by loads acting on the dental prosthesis during its use.

The invention will now be explained, for example:

Example I.

A binder with the composition listed below is made by thoroughly mixing the components manufactured.

Composition I

Aluminum powder SiO ₂ (up to 400 sieve numbers) Wt% Glass Al ₂ O ₃ Wt% Na ₂ O Wt% CaO 49.6% by weight Wt% MgO 12.04 Wt% K ₂ O 3.60 0.76 0.48 8.40

2 g 2 g

-15-

609853/0959

SnO,

Li ₂ O

^Fe 2 ° 3 BaO

Silicone oil *

-15-

21.00 wt% 1.19 wt% 0.10% by weight 0.013% by weight 0.14% by weight

approx. 1.5 ml

GE No.69 ₁ viscosity 6-17 cSt at 37.8 ° C (approx. 10O ** ¹ ); Density 8 lbs (0.454 kg) / gal (3.785 l).

The resulting composition is a fine, mushy mass that can be brushed onto metal. The listed Binder composition is painted onto a base metal alloy on flat disks. The used Alloy has the following composition in wt% 71.3% nickel; 19.1% chromium; 4.0% silicon; 4.1% molybdenum and 1.4% boron and is the subject of patent application P 26 03 860.8 of February 2, 1976.

The painted with the binder slices are dried in the door of a dental furnace and then heated in an oven to temperatures of 650-1010 ⁰ C (1200-1850 ⁰ F) in air. The disks are removed from the oven and cooled on the laboratory bench. After cooling, the disks are "brushed" with a toothbrush and water to remove loose particles of the binder, and then ultrasonically cleaned with warm water for 5 minutes and dried Opaque porcelain CERAMCO (trademark of Johnson & Johnson) is then applied to the surface and fired according to the porcelain manufacturer's instructions for use

609853/0959

of gingival porcelain CERAMCO (trademark of Johnson & Johnson) is also applied and fired. Then the porcelain layer is cut through on each test piece with a DEDICO cutting disc to get a Slot, and a screwdriver inserted into the slot and a twisting force applied to try and to break off the porcelain. The porcelain cannot, however be detached from the metal.

Example . II

Similarly, a binder of the following composition is prepared.

Composition II

Aluminum powder 2 g

Glass (oxide composition like

according to the composition I) 2g

Silicone oil (GE No.69) 2.5 ml

The composition is a pasty mass that can be brushed onto metal surfaces. ' .

The strength of the adhesion between the metal and porcelain by using the above-mentioned binder composition is determined by verification tests, jIf where di _s mechanical properties are measured as follows:

From the base metal alloy (with the composition of the example of I) are test specimens with a length of 1 cm and

609853/0959

0.95 mm (3/8 ") diameter. A pair of specimens is used for each test run. Each pair of specimens is polished at one end with sandpaper. The binder is then applied to the polished ends and sintered by placing the specimens into a preheated to 650 ⁰ C (1200 P) furnace are used, and the temperature in air at a rate from 32 to 38 ⁰ C is increased (from 90 to 100 ° F / min) to 1010 ⁰ C (1850 ⁰ F). upon reaching At 1010 ⁰ C (1850 ⁰ F), the test specimens are removed from the oven and cooled on the laboratory bench.

The test specimens are cleaned and dried in a manner similar to that in Example I. Then a layer of opaque porcelain (the same as in Example I) is applied to the binder-coated surface and fired by heating from 650 to 930 ^° C (1200 to 1700 ^° F) in a vacuum (approx. 740 mm (29 ") QS)) and from 930 to 1010 ⁰ C (1700 to 1850 ⁰ F) in air.

A second layer of the same opaque porcelain is then applied and the porcelain-coated surfaces are joined together. Enough porcelain is applied so that when the porcelain-coated ends are joined, enough porcelain protrudes over the circumference, the excess compensating for the shrinkage during firing. The assembled test specimens (test specimens) are ^{heated in an oven at temperatures from 650 to 930 °} C. (1200 to 1700 ^° F) in vacuum and from 930 to 1010 ^° C. (1700 to 1850 ^° F) in air. When 1010 ⁰ C (1850 ⁰ F) is reached, the specimens are held at this temperature for 2 min.

Control specimens were prepared without the use of binder as follows: (a) Polishing one end of each Pairs as described above for "the test specimens; (b) apply of opaque porcelain of the same composition as for the specimens on the polished ends and firing; and (c) applying a second layer of porcelain, assembling

609853/0959

of the two ends and burning; the manufacturing process only differs in the omission of the application and sintering the binder.

The excess porcelain on the specimens and the control specimens is ground off so that the diameter of the porcelain section is the same as that of metal.

The specimens are then used to study mechanical properties on "an INSTRON tester" ways Due to the small dimensions of the test pieces, special adapters are used to accommodate the test pieces, if certain Measurements are made.

The following tests are carried out:

Tensile strength: The specimens are inserted directly into the INSTRON tester and the tensile force required to break the specimen at opposite ends of the specimen is determined.

Shear strength ; The test specimens are inserted into an adapter which has two rods, each with a through opening; the through openings can be aligned one above the other and thus accommodate the test item. The specimen is positioned so that the porcelain-metal interface coincides with the interface of the two adapter rods being pulled in opposite directions. The adapter is inserted into the INSTRON tester and the force required to break the specimen is measured.

Torsional Strength : The specimens are inserted into an adapter that holds one end stationary while a torsional or twisting force is applied to the other end, and the adapter is inserted into the INSTRON tester as well

-19-

609853/0959

the relative torsional or turning force to break the test specimen is determined and recorded as the torsional value. The torsion value is understood here to be a calculated number that is equal to the product of the fracture of the test specimen necessary load and the distance from the test object / at which the force is exerted.

Three-point loading ; The test specimens are placed in a special three-point loading device which is mounted on the INSTRON test device, and the necessary compressive force for a defect at the metal-porcelain interface is measured with the INSTRON test device.

Impact test: A device is made from two metal rods held side by side. These rods are mounted so that one rod is fully rotatable while the other is held stationary in a vertical position. The test specimen is held by the stationary rod, part of which protrudes over the edge of the first rod in such a direction that it would be in the path of the second rod when it is rotated. The second rod is then pivoted with a certain force and the relative force for causing a break is determined. Impact value is understood here as a number that is equal to the linear path that must be covered by a moving rod of constant weight in order to cause the test specimen to break. The "difference between the values for the control specimen and the specimens is of greater significance than the actual numerical values. These results are shown in Table I."

609853/0959

Table I.

Mechanical properties

Tensile Strength Shear Strength Torsional 3 Point Impact

P ruf ling (kp / cm (psi)) (kp / cm (psi) strength load ^wer ^ (kp / cm ² (psi)) _

with binder 353 (5019) 414 (5889) 3.056 717 (10206) 7.6

Control test item 125 (1781) 198 (2815) 1.678 292 (4153) 3.6 without binders

Test items (with binding agent) = average of 7 to 10 measurements Control test items = mean value of 5 to 8 measurements

(excluding tensile strength, mean of two measurements).

Example III

Similarly, a binder having the following composition was prepared.

Composition III

Aluminum powder (up to 400 sieve number) 3 g

Jar 2 g

Silicone oil (GE No. 69) 2 ml

Same composition as the glass of composition I,

The composition is based on a cleaned metal core a base metal alloy of the same composition as in Example I applied. The painted metal core will then dried, sintered, cleaned and veneered with porcelains of the same composition as in Example I.

-21-

609853/0959

The porcelain layers are then incised and a rotational force according to Example I is applied. A break in the porcelain is detected, but the metal-porcelain interface remains unaffected.

Example IV

Aluminum powder and one or more glass compositions (each consisting of a mixture of oxides) will get along well Silicone oil mixed to obtain binder compositions as substantially uniform pasty masses. The amount of aluminum, each. Oxide component of the glass and the volume of the organosilicon compound in the various compositions are given in Table II.

-22-

6 0 9853/0959

TABLE II

CD O CO CO

co cn co

Zusaitrryarv Aluminipi S102 AI2O3 Fe ₂ 03 Glassy '" Wa20 K2 ^l Ö MgO SnO2 · ' Β2Ο3 BaO Sj-J-iciuiTorganiscfte settlement. : G ° t 993 3.24l 0.0003 CaO ) _t .p72 aÄ67 D. 010 3.42 LI2O 0; 002 ) _; 003 ■ '· 1
Connection (ml) ' A. 2 \ 0 *. ' il _T 302 ο, 2ββ 0.0003 3.015 3.121 } 19β 3,018 3.001 D, 024 - « '1/5 B. 2.0 * 1.148 0.254 0.0003. 3.027 3.O97- 0.182 3,014 3.211 3.020 Ο _; 001 3.0015 1.5 C. 2.0 * 1.071 ö, 248 0.0003 3.021 3,084 0.174 3 012 ^ 315 0.022 ο / οοΐ5 3 ^ 002 1/5 D. 2.0 * 1.225 0.260 0 _f 0003 O.OI8 0.109 0.189 9.016 ^, 106 0.023. 0, οοθ5 0 ₍ .oöo7 1/5 E. 2.0 * ' 0.993 0.241 £, 0003 ?, 025 O _r 072 0.1β7 ?, 010 7.42 (9,021 0.002 0 _; οο3 'F 2.0 **. 0.993 0.241 0 _f 0003 5.015 9.Ο72 9.167 } 010 9.42 0 _r O24 0.002 ί _; 003 1; 5 G 2.0 *** '' 0.993 0.241 0.0003 0.015 0.072 ³ ; 1.67 ■ 7.010 9.42 0 _; 024 9.002 0.003 1; 5 H '■ 3.0 * 1.302 0.266 0.0003 0.015 ή 121. } 196 ?, 0ΐ8 9.001 ö _T 024 - - 1 ₃ 5 I '' 2.0 *** 1.148 0.254 ö _; 0003 0.027 ^, "097 9.182 ?, οι4 5.211 0.020 Ο, οοι 9; 0015 1; 5 J 2. 0 ** 1.071 0, 248 <9 _r ooo3 0.021 9,084 ο, 174 '; ? .Ο12 9.315 0.Ο22 0 _} 0015 P., 002 K. 2.0 *** I ₇ 225 0 _; 26θ 0.0003 0, Ol8 0.109 3.189 9.016 9.106 O ₇ 023 0 _; 0005 0.0007 1; 5 '. L. 2.0 *** 0.745 Ö, 18l 0 _; 0002 J, 025 0.054 9.125 ^ 007 Ö.315 0, Ο21 Of 0015 0 _f 0Q2 . ¹ ^ κ, M. 3.5 ** · * Df 011 0jOl8 1.5 p
cn -,

¹ GE ifo, 69 Silücön-Öl. . · ..,. ■

■ ■ * · Powder with a particle size _f which passes through a sieve number 400 (mesh size 0.038 ram)

* »■ Powder with" 10_. M - particle size * ■ ** Powder with 20 * - particle size · ■

CD CD INJ

The compositions are used to test adhesive properties similar to Example I. This means, the compositions are applied to flat discs on a nickel-chromium alloy of the same composition as in the example I coated on, the coated discs are sintered, after which porcelain (opaque CERAMCO (trademark from Johnson & Johnson or subsidiaries) - porcelain) is applied to the panes and sintered, to get test items. The porcelain layer is cut and with a twisting or torsion force as above described in order to evaluate the adhesion as good or bad. If there is no peeling at the metal-porcelain interface, but if a break occurs in the porcelain, the adhesion will be as good if there is any peeling on the Interface occurs, rated as bad.

The adhesions of all specimens using the binder compositions use according to Table II are rated as good.

. Example . V

Similar to the following binder compositions are prepared in Examples I ₇ III and IV:

-24-

609853/0959

SiO ₂ 68% by weight No. 69) 2 2626092 G Al ₃ O ₃ 3.0 wt% 2 G - 24 - Na ₂ O 16% by weight Composition IV CaO 6.0 wt% Aluminum powder (up to 20 J / m) MgO 4.0% by weight Glass K ₂ O 0.5 wt% ^B 2 ° 3 1.5 wt% BaO 2.0 wt% Silicone oil (GE 1, 5 ml

Composition V

Aluminum powder (up to 20 i / m) 2 g

Jar 2 g

SiO ₂ 74% by weight , 0% by weight Al ₂ O ₃ 1 6.5 wt% Na ₂ O 1 , 0% by weight CaO 5 , 5% by weight MgO 3 Silicone oil

1.5 ml

-25-

609853/0959

Composition VI

SiO 2 Well ₂ 0 CaO MgO SnO 2 Li ₂ 0 Fe ₂ ° 3 Silicone oil

Aluminum powder (up to 20 υ m) 1.6 g

Glass 2.4g

65.1% by weight

13.3% by weight

6.07 wt%

1.37% by weight 0.92% by weight 9.78% by weight 0.05% by weight 1.01 wt% 0.015 wt%

2.0 ml

In separate steps, the compositions are applied to a cleaned metal core or substrate Base metal alloy of the following composition applied in% by weight: 71.3% nickel; 19.1% chromium; 4.6% Silicon; 3.7% molybdenum and 1.3% boron and is the subject of patent application P 26 03 860.8 of February 2, 1976.

The coated metal is sintered as described in Example I. After that, the coated metal is used with Porcelain veneered using the same porcelains and procedures as in Example I.

The samples show good adhesion of the porcelain to the metal.

-26-

609853/0959

- 26 Example VII

Similarly, a binder is made by mixing 2 g aluminum powder (2oA-m), 2 g glass powder (with the same oxide content as in composition I) and a sufficient amount (1.5 to 2.5 ml) of silicone oil (GE No. 69) to obtain a thick, easily spreadable composition.

The composition is used to make porcelain with test specimens made of a nickel-chromium alloy of the same Arrest composition as in Example I.

The test specimens are prepared for a test similar to Example II, but with the following differences:

Ten pairs of test pieces are made without changing the alloy surface used before applying the binder (unprocessed surface). With ten other pairs of test specimens the surface is sanded with a diamond disc before applying the binding agent (sanded surface) . After applying the binder, the test specimens are sintered, cleaned, coated with porcelain and fired, similar to the examples described above.

The test specimens are then used on the INSTRON tester for Examined three-point loading as described above. The results are as follows:

Unmachined surface 858 kg / cm ² (12205 psi) Ground surface 728.6 kg / cm ² (10364 psi)

609853/0959

Claims (7)

Claims (T.) Binder composition for connecting dental porcelain with a metal core made of a non-precious metal alloy in dentures, characterized by (a) an adhesion-forming component made of aluminum powder mixed with glass powder, which is in a temperature range from approx. 950 to approx. 1010 ⁰ C (1750 to 1850 ⁰ F) melts and (b) a carrier component with
a liquid organosilicon compound that
a reducing atmosphere in a temperature range of about 650 to 1050 ⁰ C (1200 to 1900 ⁰ F) can generate, wherein the glass is a mixture of oxides, which are contained therein in about the following weight percent; . - 47-74% silica; 1-16% aluminum oxide; 3-17% sodium oxide; 0.6-6% calcium oxide and 0.4-4% magnesium oxide. 2. Binder composition according to claim 1, characterized in that the glass additionally has at least one contains the following oxides in approximate percentages by weight: 0-12% potassium oxide; O-25% tin dioxide; 0-5% lithium oxide; 0-2% boric oxide and 0-2% barium oxide. 3. Binder composition according to claim 1, characterized characterized in that the carrier component is silicone oil. 4. Binder composition according to claim 1, characterized in that the glass ^{melts in the temperature range from 976 to 988 0} C (1790 to 1810 ⁰ F). -28- 609853/0959 5. Binder composition for bonding a dental porcelain with a metal core made of a base metal alloy, characterized by a mixture of aluminum powder and glass powder in silicone oil as a carrier, with a mixture of solids on each part Binder -. "_ Component approx. 0.75 - 1.25 parts by volume of the carrier liquid come, where, that Glass is a mixture of oxides, which are contained therein in approximately the following percentages by weight are: 47-74% silica; 1-16% alumina; 3-17% sodium oxide; 0.6-6% calcium oxide and 0.4-4% Magnesium oxide. 6. binder composition according to claim 5, characterized in that the ratio of aluminum to Glass is about 2.3: 1 to about 1: 1.5. 7. A method for connecting dental porcelain with a metal core .ein dentures, characterized by: 1) substantially uniform coating of the cleaned metal core with a binder composition, which has: (a) an adhesion-forming component made of aluminum powder mixed with glass powder, that in the temperature range from approx. 950 to approx. 1010 ⁰ C (1750 to 1850? F). melts and. contains approximately the following parts by weight * in percent; 47-74% silica; 1-16% Alumina; 3-17% sodium oxide; 0.6-6% calcium oxide and 0.4-4% magnesium oxide; and (b) a support component of an organosilicon compound which can generate (1200-1900 ⁰ F) a reducing atmosphere in the temperature range of about 650-1050 ⁰ C; 2) Sintering of the coated metal core by rapid heating from a temperature of approx. 650 ⁰ C (1200 ⁰ F) to a maximum temperature in the range of 609853/0959 about 980 to 1040 ° C (1800 to 1900 ⁰ F); 3) cleaning the coated and sintered surface portions; and 4) Applying the porcelain to the cleaned surface and burning. 609853/0959