Process for providing a topography to the surface of a dental implant

Abstract

A process for providing a topography to the surface of a dental implant, said surface being made of a ceramic material. At least a part of the surface of the dental implant is etched with an etching solution comprising hydrofluoric acid at a temperature of at least 70° C. Thereby, discrete grains or agglomerates of grains are removed from the ceramic material.

1 - 13 . (canceled) 
     
     
         14 . A dental implant having a surface made of a ceramic material, at least a part of said surface comprising recesses and cavities formed by the removal of discrete grains having an average grain size from 0.1 μm to 0.6 μm and/or agglomerates of these grains from the ceramic material. 
     
     
         15 . Dental implant according to  claim 14 , the shape and dimension of the cavities and recesses corresponding at least approximately to the shape and dimensions of the grains and agglomerates of grains, respectively. 
     
     
         16 . Dental implant according to  claim 14 , the ceramic material being based on zirconia. 
     
     
         17 . Dental implant according to  claim 14 , the ceramic material being yttria-stabilized zirconia. 
     
     
         18 . Dental implant according to  claim 17 , the composition of the yttria stabilized zirconia comprising 4.5 to 5.5 weight-% of Y 2 O 3  and less than 5 weight-% of HfO 2 , the total amount of ZrO 2 , Y 2 O 3  and HfO 2  being more than 99.0 weight-%. 
     
     
         19 . Dental implant according to  claim 14 , the recesses and cavities being obtainable by etching the ceramic material with an etching solution comprising hydrofluoric acid at a temperature of at least 70° C. 
     
     
         20 . Dental implant according to  claim 19 , the etching solution comprising at least 50 vol.-% of concentrated hydrofluoric acid. 
     
     
         21 . Dental implant according to  claim 20 , the etching solution further comprising at least one compound selected from the group consisting of phosphoric acid, nitric acid, ammonium fluoride,sulphoric acid, hydrogen peroxide and bromic acid, and mixtures thereof. 
     
     
         22 . Dental implant according to  claim 20 , the etching solution further comprising sulphuric acid in an amount of 50 vol.-% at most. 
     
     
         23 . Dental implant according to  claim 14 , the surface having a macroscopic roughness in addition to the recesses and cavities formed on said surface with said macroscopic roughness. 
     
     
         24 . Dental implant according to  claim 23 , the macroscopic 15 roughness being obtainable by sandblasting, milling and/or injection molding techniques. 
     
     
         25 . Dental implant according to  claim 14 , the topography of the surf ace having a Core Roughness Depth S k  of less than 1 μm. 
     
     
         26 . Dental implant according to  claim 14 , the topography of the surface having a negative Skewness S sk .