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US4302376A
Expired / Lapsed
US
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Dental materials which are opaque to X-rays and are based on organic plastics in paste form
Assignee: Bayer AG
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Filing: 1979-11-19
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Granted: 1981-11-24
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Expires: 1999-11-19
Abstract
Abstract The invention provides dental materials which are opaque to X-rays and are based on organic plastics in paste form, which comprises (a) a polymerizable binder, (b) a crosslinked bead polymer and (c) an X-ray contrast medium. The materials can also contain as an additional component (d) a fine-particled inorganic filler which is not opaque to X-rays. The materials are useful, inter alia, for filing dental cavities.
Inventors
- 👤 Michael Walkowiak
- 👤 Wolfgang Podszun
- 👤 Bernhard Leusner
- 👤 Carlhans Suling
- 👤 Hans H. Schulz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:44
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/884; A61K6/887; Y; Y10; Y10S; Y10S528/00; Y10S528/92
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
53 words
A dental paste opaque to X-rays, consisting essentially of (a) at least one ester of methacrylic acid and a monohydric or polyhydric alcohol as polymerizable binder, (b) at least one crosslinked bead polymer plastic made from an ester of methacrylic acid and a monohydric or polyhydric alcohol, and (c) an X-ray contrast medium.
Claim 2
Dependent Claim
53 words
A dental paste opaque to X-rays, consisting essentially of (a) at least one ester of methacrylic acid and a monohydric or polyhydric alcohol as polymerizable binder, (b) at least one crosslinked bead polymer plastic made from an ester of methacrylic acid and a monohydric or polyhydric alcohol, and (c) an X-ray contrast medium.
Claim 3
Dependent Claim
18 words
The paste according to claim 1 further containing a fine-particled inorganic filler which is not opaque to X-rays.
Claim 4
Dependent Claim
37 words
The paste according to claim 1 or 2 wherein the polymerizable binder is present in an amount more than 80% by weight based on the weight of at least one aliphatic or cycloaliphatic ester of methacrylic acid.
Claim 5
Dependent Claim
37 words
The paste according to claim 1, wherein the polymerisable binder contains at least 50% by weight, based on the total weight of binder, of an ester of methacrylic acid having at least two ethylenically unsaturated double bonds.
Claim 6
Dependent Claim
22 words
A dental material according to claim 1, in which the polymerisable binder is a mixture of methacrylic acid aliphatic or cycloaliphatic esters.
Claim 7
Dependent Claim
36 words
The paste according to claim 1, wherein the bead polymer is made from monomers comprising more than 50% by weight, based on the total weight of bead polymer, of one or more esters of methacrylic acid.
Claim 8
Dependent Claim
22 words
A dental paste according to claim 1, in which the crosslinked bead polymer has an average particle size of 10 to 100μ.
Claim 9
Dependent Claim
28 words
A dental paste according to claim 1, in which the X-ray contrast medium is a solid, sparingly soluble inorganic substance with an average particle size of 1 mμ-5μ.
Claim 10
Dependent Claim
22 words
A dental paste according to claim 2, in which the additional fine-particle inorganic filler has an average particle size of 1 mμ-1μ.
Claim 11
Dependent Claim
19 words
A dental paste according to claim 2, in which the additional fine-particled inorganic filler consists of amorphous silicon dioxide.
Claim 12
Dependent Claim
25 words
A dental material according to claim 2, in which the proportion of additional inorganic filler is up to 28% by weight of said inorganic filler.
Claim 13
Dependent Claim
32 words
A dental material according to claim 2, in which the proportion of crosslinked bead polymer, X-ray contrast medium and inorganic filler, together is 51 to 82% by weight of said inorganic filler.
Claim 14
Dependent Claim
25 words
A dental material according to claim 1, in which the proportion of X-ray contrast medium is 5 to 45% by weight of said dental paste.
References Cited (Backward Citations)
US4032504A
Cited
US3959212A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-23 | 1985-05-25 | 1985-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-23 | 1989-05-25 | 1989-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-23 | 1993-05-25 | 1993-11-24 | $7700.00 | Window Closed / Lapsed |