Lithium Silicate Glass Ceramic and Glass with ZrO2 Content

Abstract

Lithium silicate glass ceramics and glasses are described which can advantageously be applied to zirconium oxide ceramics in particular by pressing-on in the viscous state and form a solid bond with these.

1 ) A dental restoration comprising:
 a lithium disilicate glass ceramic coated on a zirconium oxide ceramic, wherein the lithium disilicate glass ceramic includes from 55 to 71 weight percent SiO 2 , from 9 to 17 weight percent Li 2 O, and at least 6.1 weight percent ZrO 2  based on a mass of the lithium disilicate glass ceramic, and wherein there are practically no flaws or cracks in the lithium disilicate glass ceramic after the lithium disilicate glass ceramic is coated on the zirconium oxide ceramic.   
     
     
         2 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic has a SiO 2 /Li 2 O molar ratio of 1.8 to 3. 
     
     
         3 ) The dental restoration of  claim 2 , wherein the lithium disilicate glass ceramic has a SiO 2 /Li 2 O molar ratio of 2 to 2.8. 
     
     
         4 ) The dental restoration of  claim 3 , wherein the lithium disilicate glass ceramic has a SiO 2 /Li 2 O molar ratio of 2.1 to 2.6. 
     
     
         5 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic comprises 6.1 to 16 weight percent ZrO 2  based on the mass of the lithium disilicate glass ceramic. 
     
     
         6 ) The dental restoration of  claim 5 , wherein the lithium disilicate glass ceramic comprises 6.1 to 14 weight percent ZrO 2  based on the mass of the lithium disilicate glass ceramic. 
     
     
         7 ) The dental restoration of  claim 6 , wherein the lithium disilicate glass ceramic comprises 6.1 to 12 weight percent ZrO 2  based on the mass of the lithium disilicate glass ceramic. 
     
     
         8 ) The dental restoration of  claim 1 , wherein the zirconium oxide ceramic further comprises at least one oxide of Ce, Y, Sr, Ca, or Mg. 
     
     
         9 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic further comprises Y 2 O 3 , and wherein the lithium disilicate glass ceramic includes a combined amount of ZrO 2  and Y 2 O 3  of greater than 6.1 to 16 weight percent based on the mass of the lithium disilicate glass ceramic. 
     
     
         10 ) The dental restoration of  claim 9 , wherein the lithium disilicate glass ceramic includes a combined amount of ZrO 2  and Y 2 O 3  of greater than 6.1 to 14 weight percent based on the mass of the lithium disilicate glass ceramic. 
     
     
         11 ) The dental restoration of  claim 10 , wherein the lithium disilicate glass ceramic includes a combined amount of ZrO 2  and Y 2 O 3  of greater than 6.1 to 12 weight percent based on the mass of the lithium disilicate glass ceramic. 
     
     
         12 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic further comprises an oxide of pentavalent elements, wherein the oxide of the pentavalent elements is Bi 2 O 5 . 
     
     
         13 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic further comprises an oxide of hexavalent elements selected from WO 3  or MoO 3 . 
     
     
         14 ) The dental restoration of  claim 1 , wherein the dental restoration is an inlay, onlay, crown, or abutment. 
     
     
         15 ) The dental restoration of  claim 1 , wherein no Na 2 O oxide is present in the lithium disilicate glass ceramic. 
     
     
         16 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic further comprises at least 0.2 weight percent to less than 5.0 weight percent Al 2 O 3 . 
     
     
         17 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic further comprises 0.2 to 3.5 weight percent Al 2 O. 
     
     
         18 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic has a biaxial strength of from 200 to 500 MPa. 
     
     
         19 ) The dental restoration of  claim 1 , wherein the lithium disilicate glass ceramic includes lithium disilicate crystals with a small-plate shaped crystal form. 
     
     
         20 ) A method comprising:
 a) melting a composition comprising lithium disilicate as a main phase;   b) heating the composition such that nucleation occurs;   c) optionally mixing the composition from b) with at least one coloring pigment; and   d) coating a layer of lithium disilicate glass ceramic on a zirconium oxide ceramic wherein there are practically no flaws or cracks in the lithium disilicate glass ceramic after the coating.   
     
     
         21 ) The method of  claim 20 , wherein the coating comprises pressing the layer of lithium disilicate glass ceramic on the zirconium oxide ceramic. 
     
     
         22 ) The method of  claim 21 , wherein the pressing occurs at a temperature from 700° C. to 900° C. 
     
     
         23 ) The method of  claim 20 , wherein the coating comprises sintering the layer of lithium disilicate glass ceramic on the zirconium oxide ceramic. 
     
     
         24 ) The method of  claim 20 , wherein the composition comprising lithium disilicate as the main phase further comprises Na 2 O. 
     
     
         25 ) The method of  claim 20 , wherein the lithium disilicate glass ceramic further comprises nuclei suitable for forming lithium metasilicate and/or lithium disilicate crystals. 
     
     
         26 ) The method of  claim 20 , further comprising contacting the melted composition with water such that a glass frit is formed. 
     
     
         27 ) The method of  claim 26 , further comprising forming a powder from the glass frit.