Process for producing roughened surface patterns on surface of interbody devices

Abstract

Processes for producing interbody spinal implants having a body with a top surface, a bottom surface, opposing lateral sides, opposing anterior and posterior portions, a substantially hollow center, and a single vertical aperture; and optionally, one or two integration plates affixed to the body. The processes include applying an additive process, a subtractive process, or both processes to at least one surface of the interbody spinal implant to form a roughened surface topography having a regular repeating pattern. The roughened surface topography is specifically designed to provide certain frictional characteristics, load dispersion, and to influence the biological responses that occur during bone healing and fusion.

What is claimed is: 
     
         1 . A process of producing an interbody spinal implant having a roughened surface pattern, comprising
 providing an interbody spinal implant comprising a body that is generally oval-shaped in transverse cross section, and comprises a top surface, a bottom surface, opposing lateral sides, opposing anterior and posterior portions, a sharp edge at the junction of the anterior portion and the top surface and at the junction of the anterior portion and the bottom surface to resist pullout of the implant once inserted in the intervertebral space, a substantially hollow center, and a single vertical aperture-extending from the top surface to the bottom surface, having maximum width at its center, and defining a transverse rim on the top surface and on the bottom surface, said transverse rim having a posterior thickness greater than an anterior thickness, and having a blunt and radiused portion along the top of each lateral side and the top of the posterior portion, and   depositing a roughened surface pattern onto the portion of the transverse rim that is not blunt and radiused, but not onto the blunt and radiused portion of the transverse rim.   
     
     
         2 . The process of  claim 1 , further comprising applying a protective maskant to each surface of the implant except for the portion of the transverse rim that is not blunt and radiused prior to the depositing step. 
     
     
         3 . The process of  claim 1 , wherein the depositing comprises sputter depositing, vacuum depositing, physical vapor depositing, chemical vapor depositing, or spin coating. 
     
     
         4 . The process of  claim 3 , wherein the sputter depositing comprises direct current (DC) sputtering, DC magnetron sputtering, alternating current (AC) sputtering, pulse DC sputtering, or radio frequency (RF) sputtering. 
     
     
         5 . The process of  claim 3 , wherein the depositing step is carried out using an ink jet printer. 
     
     
         6 . The process of  claim 1 , wherein the roughened surface pattern comprises an array. 
     
     
         7 . The process of  claim 6 , wherein the array comprises an array of dots, spheres, or semi-spheres. 
     
     
         8 . The process of  claim 6 , wherein the array comprises an array of amorphous shapes. 
     
     
         9 . The process of  claim 1 , wherein the roughened surface pattern is oriented in a direction opposite to the direction of biologic forces. 
     
     
         10 . The process of  claim 1 , wherein the roughened surface pattern is oriented in a direction opposite to the direction in which the implant is inserted into the intervertebral space. 
     
     
         11 . The process of  claim 1 , wherein the roughened surface pattern promotes bone growth, fusion, and healing. 
     
     
         12 . The process of  claim 1 , wherein the roughened surface pattern comprises a roughness average amplitude, Ra, of about 1-200. 
     
     
         13 . The process of  claim 1 , wherein the body comprises poly ether ether ketone (PEEK). 
     
     
         14 . The process of  claim 13 , wherein the roughened surface pattern comprises titanium or a titanium alloy. 
     
     
         15 . The process of  claim 1 , wherein the body comprises titanium or a titanium alloy. 
     
     
         16 . The process of  claim 1 , wherein the single vertical aperture of the body has a size and shape predetermined to maximize the surface area of the top surface and the bottom surface available proximate the anterior and posterior portions.