Connection of a prosthesis structure with an implant structure

Abstract

A connection device for connecting a prosthesis structure with an implant structure comprises a holding shell and a retention insert. The retention insert comprises an end side and a substantially ring-shaped retention rim projecting therefrom. The holding shell comprises an end side and a substantially ring-shaped holding rim projecting therefrom. The holding rim and the end side of the holding shell form a retainer in which the retention insert can be arranged such that an outer surface of the retention rim is adjacent to an inner surface of the holding rim. Moreover, the outer surface of the retention rim is at least partly spaced from and adjacent to the inner surface of the holding rim when the retention insert is arranged in the retainer of the holding shell and when essentially no radial forces are acting on the holding rim and on the retention rim. In that the adjacent outer surface of the retention rim and inner surface of the holding rim are at least partly not contacting each other but are spaced from each other when essentially no radial forces are acting on the holding rim and on the retention rim, it can, i.a., be achieved that the retention insert is connected relatively loosely with the holding shell when the connection device has not yet been placed on the implant structure. This loose connection can allow the retention insert to be relatively easily removed from the holding shell and inserted in the holding shell without having to be substantially deformed or strained in any other way. Thus, it is possible to insert and remove the retention insert gently, which can improve the flexibility and lifetime of the connection device.

1 . A connection device for connecting a prosthesis structure with an implant structure or a capped tooth,
 said connection device comprising a holding shell and a retention insert,   wherein said retention insert has an end side and a substantially ring-shaped retention rim projecting therefrom,   and said holding shell has an end side and a substantially ring-shaped holding rim projecting therefrom,   wherein said holding rim and said end side of said holding shell form a retainer in which said retention insert can be arranged such that an outer surface of said retention rim of said retention insert is adjacent to an inner surface of said holding rim of said holding shell,   wherein   said outer surface of said retention rim of said retention insert is, at least partly, spaced from and adjacent to said inner surface of said holding rim of said holding shell when said retention insert is arranged in the retainer of said holding shell, and   when essentially no radial forces are acting on said holding rim of said holding shell and on said retention rim of said retention insert.   
     
     
         2 . The connection device according to  claim 1 , wherein said outer surface of said retention rim of said retention insert is, at least partly, spaced from and adjacent to said inner surface of said holding rim of said holding shell in that said outer surface of said retention rim of said retention insert is more strongly inclined in the direction of a central axis of said connection device than said inner surface of said holding rim of said holding shell. 
     
     
         3 . The connection device according to  claim 1 , wherein said retention rim of said retention insert comprises recesses starting from an end of said retention rim facing away from said end side of said retention insert and extending in the direction of said end side of said retention insert. 
     
     
         4 . The connection device according to  claim 3 , wherein said recesses in said retention rim of said retention insert extend over at least about 50% of the width of said retention rim of said retention insert. 
     
     
         5 . The connection device according to  claim 3 , wherein said retention rim of said retention insert comprises three, four, five or six recesses. 
     
     
         6 . The connection device according to  claim 1 , wherein said retention rim of said retention insert has a projection projecting radially from said outer surface of said retention rim of said retention insert and said holding rim of said holding shell comprises a corresponding groove extending radially from said inner surface of said holding rim of said holding shell. 
     
     
         7 . The connection device according to  claim 6 , wherein said projection of said retention rim of said retention insert is arrangeable in said groove of said holding rim of said holding shell such that said retention insert is releasably held in said holding shell when said retention insert is arranged in the retainer of said holding shell and when essentially no radial forces are acting on said holding rim of said holding shell and on said retention rim of said retention insert. 
     
     
         8 . The connection device according to  claim 6 , wherein said projection of said retention rim of said retention insert comprises a substantially planar projection supporting surface and said groove of said holding rim of said holding shell comprises a substantially planar groove supporting surface, wherein a part of said projection supporting surface contacts a part of said groove supporting surface
 when said retention insert is arranged in the retainer of said holding shell, and   when essentially no radial forces are acting on said holding rim of said holding shell and on said retention rim of said retention insert, and   wherein said groove supporting surface is rounded towards its end facing said retention insert and/or said projection supporting surface is rounded towards its end facing said holding shell.   
     
     
         9 . The connection device according to  claim 6 , wherein said projection of said retention rim of said retention insert can be arranged in said groove of said holding rim of said holding shell such that said retention insert is permanently connected with said holding shell when said retention insert is arranged in the retainer of said holding shell and when a radial force is acting on said retention rim of said retention insert in the direction of said holding rim of said holding shell and/or on said holding rim of said holding shell in the direction of said retention rim of said retention insert. 
     
     
         10 . The connection device according to  claim 1 , wherein said retention rim of said retention insert comprises an inner surface opposite to said outer surface, wherein said inner surface is rounded towards an end facing away from the end side of said retention insert. 
     
     
         11 . The connection device according to  claim 1 , wherein said retention insert and/or said holding shell is/are made of a biocompatible polymeric material, in particular of a polyetheretherketone. 
     
     
         12 . A retention insert of a connection device for connecting a prosthesis structure with an implant structure according to  claim 1 , wherein the retention insert has an end side and a substantially ring-shaped retention rim projecting therefrom, wherein said retention rim of said retention insert optionally comprises recesses starting from an end of said retention rim facing away from said end side of said retention insert and extending in the direction of said end side of said retention insert. 
     
     
         13 . A method for connecting a prosthesis structure with an implant structure via a connection device according to  claim 1 , wherein said holding shell of said connection device is firmly mounted to the prosthesis structure and wherein the implant structure comprises a head suitable for a snap-engagement connection, wherein
 said retention insert of said connection device is moved axially into said holding shell of the connection device until said retention insert is arranged in said holding shell,   the prosthesis structure is arranged at the implant structure so that the head of the implant structure contacts said retention insert of said connection device, and   the prosthesis structure is pressed on the implant structure so that said retention insert is pressed axially on the head of the implant structure, wherein a radial force is acting on said retention rim of said retention insert so that said retention rim is moved at least partly in the direction of said holding rim of said holding shell.   
     
     
         14 . A demounting tool for demounting a retention insert from a holding shell of a connection device according to  claim 1 , the demounting tool comprising a sleeve-shaped head which can be arranged between an outer surface of a retention rim of said retention insert and an inner surface of a holding rim of said holding shell when said retention insert is arranged in a retainer of said holding shell, wherein an inner side of said head is conical so that said retention rim of said retention insert is moved in the direction of a central axis of said connection device when said head of said demounting tool is arranged between said outer surface of said retention rim of said retention insert and said inner surface of said holding rim of said holding shell. 
     
     
         15 . The demounting tool according to  claim 14 , wherein the distal end of said head is tapered. 
     
     
         16 . The connection device according to  claim 4 , wherein said recesses in said retention rim of said retention insert extend over at least about 70% of the width of said retention rim of said retention insert. 
     
     
         16 . The connection device according to  claim 4 , wherein said recesses in said retention rim of said retention insert extend over at least about 80% of the width of said retention rim of said retention insert.