Dental composition

Patent metadata

Field	Value
Publication number	US-2016143818-A1
Application number	US-201615011021-A
Country	US
Kind code	A1
Filing date	Jan 29, 2016
Priority date	Dec 15, 2009
Publication date	May 26, 2016
Grant date	—

Abstract

A dental cement hardened by a cement reaction involving the specific polymerizable polyacidic polymer and optionally additional crosslinkable groups, has reduced shrinkage and improved mechanical properties, in particular with regard to flexural strength and fracture toughness. Moreover, the specific polymerizable polyacidic polymer of the present invention contains a high number of acidic groups which is not reduced by the presence of polymerizable moieties, whereby water solubility of the uncured polymer is not impaired by the presence of the polymerizable moieties.

First claim

What is claimed:

1 . Dental cement composition comprising a polymerizable polyacidic polymer having repeating units in the polymer backbone, which are represented by the following formula (I), (II), and/or (Ill):

wherein
X represents O, S, or NR′, whereby R′ represents a hydrogen atom or a straight or branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,
Y a group of the following formula (IV)

wherein each of L 1 , L 2 , L 3 and L 4 ,
which are independent from each other represents a single bond, a straight or branched C 1 -C 6 alkylene group, a straight or branched C 1 -C 6 alkenylene, or a straight or branched C 1 -C 20 alkylene group which includes 1 to 8 atoms selected from oxygen and sulfur atoms,

X′ represents O, S, or NR″, whereby R″ represents a hydrogen atom or a straight or
branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,

m is 0 to 3, and
n is 1 to 3.

2 . The dental cement composition according to claim 1 , wherein the polymerizable polyacidic polymer is obtainable by a process comprising the steps of
(i) copolymerizing a mixture containing acrylic acid and one or more monomers selected from the group of maleic anhydride and itaconic anhydride, and (ii) reacting the reaction product with HXY, wherein X and Y are as defined in claim 1 .

3 . The dental cement composition according to claim 2 , wherein said polymerizable polyacidic polymer is obtainable by copolymerizing a mixture containing acrylic acid and itaconic acid anhydride.

4 . The dental cement composition according to claim 1 , wherein
XY is —OCH 2 C(═CH 2 )COOH.

5 . The dental cement composition according to claim 1 , wherein the polymerizable polyacidic polymer is water-soluble.

6 . The dental cement composition according to claim 1 , which contains a polymerizable polyacidic polymer having repeating units represented by the formula (I) wherein a portion of the groups Y is a group of the following formula (V)

wherein
L 5 represents a single bond or a straight or branched C 1 -C 6 alkylene group,
L 6 represents a straight or branched C 1 -C 3 alkylene group, and
m is as defined in claim 1 .

7 . The dental cement composition according to claim 1 , which further comprises a polymerization initiator system and optionally a polymerizable monomer having at least two polymerizable functional groups.

8 . The dental cement composition according to claim 1 , which further comprises a particulate glass comprising
a. 20-25% by weight of silica b. 20-25% by weight of alumina c. 18-21% by weight of CaO plus SrO d. 13-18% by weight of zinc oxide e. 14-18% by weight of P 2 O 5 f. 4-7% by weight of fluoride, and wherein the content of Na 2 O is less than 1% by weight.

9 . The dental cement composition according to claim 8 , wherein the mean particle size of the particulate glass is in the range of from 0.1 to 100 μm.

10 . The dental cement composition according to claim 1 , wherein said polymerizable polyacidic polymer has a mean molecular weight, Mw, between 10000 and 500000.

11 . Process for preparing a polymerizable polyacidic polymer having repeating units in the polymer backbone which are represented by the following formula (I) and/or (II):

wherein
X represents O, S, or NR′, whereby R′ represents a hydrogen atom or a straight or branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,
Y a group of the following formula (IV)

wherein each L 1 , L 2 , L 3 and L 4 ,
which are independent from each other represents a single bond, a straight or branched C 1 -C 6 alkylene group, a straight or branched C 1 -C 6 alkenylene, or a straight or branched C 1 -C 20 alkylene group which includes 1 to 8 atoms selected from oxygen and sulfur atoms,

X′ represents O, S, or NR″, whereby R″ represents a hydrogen atom or a straight or branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,
m is 0 to 3, and
n is 1 to 3,
said process comprising the steps of
(i) copolymerizing a mixture containing acrylic acid and one or more monomers selected from the group of maleic anhydride, itaconic anhydride, and
(ii) reacting the reaction product of (i) with HXY, wherein X and Y are as defined in claim 1 .

12 . Process for preparing a polymerizable polyacidic polymer having repeating units in the polymer backbone which are represented by the following formula (III)

wherein
X represents O, S, or NR′, whereby R′ represents a hydrogen atom or a straight or branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,
Y a group of the following formula (IV)

wherein each L 3 and L 4
which are independent from each other represents a single bond, a straight or branched C 1 -C 6 alkylene group, a straight or branched C 1 -C 6 alkenylene, or a straight or branched C 1 -C 20 alkylene group which includes 1 to 8 atoms selected from oxygen and sulfur atoms,

X′ represents O, S, or NR″, whereby R″ represents a hydrogen atom or a straight or branched C 1 -C 6 alkyl group, C 3 -C 6 cycloalkyl group, or C 4 -C 8 cycloalkylalkyl group,
m is 0 to 3, and
n is 1 to 3,
said process comprising the steps of reacting a carboxylic acid anhydride of YCOOH, wherein Y is as defined in claim 1 , with a polymer or copolymer containing repeating units of the following formula (V):

wherein X is as defined in claim 1 .

13 . Polymerizable polyacidic polymer obtainable according to the process of claim 11 .

14 . The polymerizable polyacidic polymer as defined by claim 13 configured to be used in a dental cement composition.

Assignees

• Dentsply Int Inc

Inventors

• Klee Joachim E
• Ritter Helmut
• Pohle Sven
• Elsner Oliver
• Bardts Mareike

Classifications

• C08F218/06 Primary

  Vinyl formate · CPC title

• A61K6/887

  Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• A61K6/889 Primary

  Polycarboxylate cements; Glass ionomer cements · CPC title

• A61K6/54

  Filling; Sealing · CPC title

• C08F265/02

  on to polymers of acids, salts or anhydrides · CPC title