Ceramic implant

Abstract

A ceramic implant, in particular a dental implant, is provided, which has a ceramic, endosseous surface region, in other words, which is to say a region that is intended to be embedded into the bone tissue and that is made of a ceramic material. The surface region has at least one first zone having a surface modification, in which first zone the surface is roughened or porous, and at least one second zone, in which the surface is not roughened or porous.

1 . A ceramic implant, in particular a dental implant, comprising:
 a ceramic endosseous surface area of an endosseous portion of the implant,   wherein the ceramic endosseous surface area has, at least in one axial partial area, a first region, in which the surface is provided with a surface modification in the form of a roughening or porous structure, and the ceramic endosseous surface area has, in this partial area, at least one second region, in which the surface is not provided with said surface modification or is provided only to a lesser extent with said surface modification.   
     
     
         2 . The implant as claimed in  claim 1 , wherein the at least one second region is present at locations where a load-bearing implant cross section is smaller than at locations with the at least one first region. 
     
     
         3 . The implant as claimed in  claim 1 , wherein the endosseous portion of the implant has retention and/or anti-rotation structures, and in that elevations of these retention and/or anti-rotation structures are designed at least partially as first regions, whereas depressions present between these elevations are designed as second regions. 
     
     
         4 . The implant as claimed in  claim 3 , wherein the retention and/or anti-rotation structures have a thread, wherein thread crests and areas of thread flanks are designed as first regions, and a thread root is designed as second region. 
     
     
         5 . The implant as claimed in  claim 1 , wherein it is a one-part and integral dental implant produced from a material based on zirconia, alumina, or zirconia and alumina. 
     
     
         6 . The implant as claimed in  claim 1 , wherein a maximum peak-to-valley height of the first regions is at least 3 μm, and a maximum peak-to-valley height of the second regions is at most 2 μm. 
     
     
         7 . The implant as claimed in  claim 1 , wherein the surface modification in the form of a roughening has a plurality of trenches arranged at regular intervals to one another and having an average depth of between 0.5 μm and 35 μm, preferably between 3 μm and 35 μm. 
     
     
         8 . The implant as claimed in  claim 1 , wherein the surface modification in the form of a roughening is brought about by means of a laser ablation method. 
     
     
         9 . A method for producing an implant, in particular a dental implant, wherein the implant has a ceramic endosseous surface area of an endosseous portion comprising the steps of:
 in a first step, the implant is brought to the intended shape and,   in a second step, the implant surface is modified in order to obtain a roughening or porous structure for promoting osseointegration,   wherein in the second step, the implant surface is modified only in first regions of a ceramic endosseous surface area, whereas second regions of the ceramic endosseous surface area are not provided with the surface modification or are provided only to a lesser extent with the surface modification.   
     
     
         10 . The method as claimed in  claim 9 , wherein the surface modification is performed by ablation methods by means of a directed ablation medium. 
     
     
         11 . The method as claimed in  claim 10 , wherein the directed ablation medium is a laser beam, as a result of which the surface modification is performed with a focussed laser beam. 
     
     
         12 . The method as claimed in  claim 11 , wherein the laser is focused such that the depth of field is less than the height of characteristic elevations in the area of the endosseous surface area. 
     
     
         13 . The method as claimed in  claim 11 , wherein a movement of the focused laser beam, relative to the implant, and the output of the laser beam are controlled such that the laser beam has a substantially ablating action only at locations belonging to the first regions. 
     
     
         14 . The method as claimed in  claim 10 , wherein the direction from which the medium acts is at a smaller angle (α), to an axis of the implant, than a maximum angle of slope (β), to the implant axis, of elevations of the endosseous surface area, as a result of which these elevations cast a shadow on depressions lying between the elevations. 
     
     
         15 . The method as claimed in  claim 9 , wherein in the second step, the second regions are covered by a mask.