Patent Publication Number: US-2018028289-A1

Title: Dental implant installation assembly and coated implantation tool therefore

Description:
REFERENCE TO RELATED APPLICATIONS 
     Reference is hereby made to U.S. Provisional Patent Application 62/128,054 , entitled DENTAL IMPLANT SYSTEM AND METHOD, filed Mar. 4, 2015, the disclosure of which is hereby incorporated by reference and plenty of which is hereby claimed pursuant to 37 CFR 1.78(a)(4) and (5)(i). 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to dental implants and more specifically to dental implant installation assemblies. 
     BACKGROUND OF THE INVENTION 
     Various types of dental implant installation assemblies are known in the art. 
     SUMMARY OF THE INVENTION 
     The present invention seeks to provide novel dental implant installation assemblies and methods, particularly well-suited for use with dental implants susceptible to damage during installation. The present invention further seeks to provide a coated implantation tool suitable for use with the assemblies and methods of the present invention. 
     There is thus provided in accordance with a preferred embodiment of the present invention a dental implant installation assembly including a dental implant body having an opening and at least a first surface peripheral to the opening, an implantation tool having a portion adapted for insertion in the opening and at least a second surface peripheral to the portion and a screw for connecting the implantation tool to the dental implant body such that when the portion is inserted in the opening and the at least first and second surfaces are in mutual contact and a torque is exerted by the implantation tool on the dental implant body during installation of the dental implant body, the torque is distributed over the dental implant body at least as a torsion torque at the opening and a friction torque at the first surface. 
     Preferably, the dental implant body includes zirconia. 
     Preferably, the implantation tool includes titanium and has a titanium oxide coating integrally formed thereon. 
     Preferably, the portion includes a protrusion. 
     In accordance with a preferred embodiment of the present invention the opening includes a generally hexagonally shaped opening and the portion includes a generally hexagonally shaped portion. 
     Preferably, the dental implant body includes an internal threaded bore adapted for receipt of the screw therein. 
     Preferably, the implantation tool includes a cylindrical body having an additional internal bore adapted for receipt of the screw therein. 
     Preferably, the dental implant body includes an annular generally flat uppermost surface circumferentially surrounding the opening, a chamfered outwardly sloping segment abutting the uppermost surface and a chamfered inwardly sloping segment abutting the chamfered outwardly sloping segment. 
     In accordance with a preferred embodiment of the present invention, the implantation tool includes a flat base peripheral to the portion, the uppermost surface including the at least first surface, the flat base including the at least second surface. 
     In accordance with another preferred embodiment of the present invention, the implantation tool includes a beveled side wall peripheral to the portion, the chamfered outwardly sloping segment including the at least first surface, the beveled side wall including the at least second surface. 
     In accordance with still another preferred embodiment of the present invention, the implantation tool includes a beveled side wall and a flat apex peripheral to the portion, the uppermost surface and the chamfered outwardly sloping segment including the at least first surface, the flat apex and the beveled side wall including the at least second surface. 
     Preferably, the beveled side wall exerts internally directed radial forces on the dental implant body, the internally directed radial forces opposing the torsion torque, 
     Preferably, the second surface peripheral to the portion includes a continuous surface. 
     Alternatively, the second surface peripheral to the portion includes a segmented surface. 
     Preferably, the implantation tool includes a multiplicity of holes adapted for receipt of a tool therein. 
     Preferably, the torque is exerted by the implantation tool on the dental implant body by manually twisting the implantation tool. 
     Preferably, a torque ratchet is used to manually twist the implantation tool. 
     Preferably, an anti-rotation tool is used to secure the implantation tool during disassembly of the dental implant installation assembly following installation of the dental implant body. 
     Preferably, the implantation tool is a single-use tool. 
     There is additionally provided, in accordance with another preferred embodiment of the present invention, a method for installing a dental implant body, including providing a dental implant body having an opening and at least a first surface peripheral to the opening, providing an implantation tool having a portion adapted for insertion in the opening and at least a second surface peripheral to the portion, connecting the implantation tool to the dental implant body using a screw, such that the portion is inserted in the opening and the at least first and second surfaces are in mutual contact and exerting a torque on the dental implant body by the implantation tool, the torque being distributed over the dental implant body at least as a torsion torque at the opening and a friction torque at the first surface. 
     Preferably, the dental implant body includes zirconia. 
     Preferably, the implantation tool includes titanium and has a titanium oxide coating integrally formed thereon. 
     Preferably, the portion includes a protrusion. 
     In accordance with a preferred embodiment of the method of the present invention, the opening includes a generally hexagonally shaped opening and the portion includes a generally hexagonally shaped portion. 
     Preferably, the dental implant body includes an internal threaded bore adapted for receipt of the screw therein. 
     Preferably, the implantation tool includes a cylindrical body having an additional internal bore adapted for receipt of the screw therein. 
     Preferably, the dental implant body includes an annular generally flat uppermost surface circumferentially surrounding the opening, a chamfered outwardly sloping segment abutting the uppermost surface and a chamfered inwardly sloping segment abutting the chamfered outwardly sloping segment. 
     In accordance with a preferred embodiment of the present invention, the implantation tool includes a flat base peripheral to the portion, the uppermost surface including the at least first surface, the flat base including the at least second surface. 
     In accordance with another preferred embodiment of the present invention, the implantation tool includes a beveled side wall peripheral to the portion, the chamfered outwardly sloping segment including the at least first surface, the beveled side wall including the at least second surface. 
     In accordance still another preferred embodiment of the present invention, the implantation tool includes a beveled side wall and a flat apex peripheral to the portion, the uppermost surface and the chamfered outwardly sloping segment including the at least first surface, the flat apex and the beveled side wall including the at least second surface. 
     Preferably, the beveled side wall exerts internally directed friction forces on the dental implant body, the internally directed friction forces opposing the torsion torque. 
     Preferably, the second surface peripheral to the portion includes a continuous surface. 
     Alternatively, the second surface peripheral to the portion includes a segmented surface. 
     Preferably, the implantation tool includes a multiplicity of holes adapted for receipt of a tool therein. 
     Preferably, the torque is exerted by the implantation tool on the dental implant body by manually twisting the implantation tool. 
     Preferably, a torque ratchet is used to manually twist the implantation tool. 
     Preferably, an anti-rotation tool is used to secure the implantation tool during disassembly of the dental implant installation assembly, following installation of the dental implant body. 
     Preferably, the implantation tool is a single-use tool. 
     There is further provided, in accordance with still another preferred embodiment of the present invention a method for preparing a coated titanium element including providing an element including titanium, immersing the element in an electrolyte, providing a cathode in the electrolyte and applying a voltage between the cathode and the element, thereby causing a titanium oxide coating to be formed on the element. 
     Preferably, the element includes a dental tool. 
     Preferably, the dental tool includes an implantation tool. 
     Preferably, the method also includes cleaning the element prior to the immersing. 
     Preferably, the method also includes surface-etching the titanium element prior to the immersing. 
     Preferably, the electrolyte includes an aqueous acidic electrolyte. 
     Preferably, the titanium element includes pure unalloyed titanium. Additionally or alternatively, the titanium element includes a titanium alloy. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which: 
         FIGS. 1A, 1B, 1C and 1D  are simplified schematic respective isometric, front, cross-sectional and exploded view illustrations of a dental implant installation assembly, constructed and operative in accordance with a preferred embodiment of the present invention; 
         FIGS. 2A, 2B and 2C  are simplified schematic respective front, cross-sectional and top view illustrations of a dental implant useful in a dental implant installation assembly of the type shown in  FIGS. 1A-1D ; 
         FIGS. 3A, 3B and 3C  are simplified schematic respective front, cross-sectional and top view illustrations of an implantation tool useful in a dental implant installation assembly of the type shown in  FIGS. 1A-1D . 
         FIGS. 4A, 4B  are  4 C are simplified schematic respective isometric, front and cross-sectional view illustrations of a dental implant installation assembly, constructed and operative in accordance with another preferred embodiment of the present invention; 
         FIGS. 5A, 5B and 5C  are simplified schematic respective front, cross-sectional and top view illustrations of an implantation tool useful in a dental implant installation assembly of the type shown in  FIGS. 4A-4C : 
         FIG. 6  is a simplified top view illustration of a dental implant useful in a dental implant installation assembly of the type shown in  FIGS. 4A-4C , showing forces acting thereon; 
         FIGS. 7A, 7B  are  7 C are simplified schematic respective isometric, front and cross-sectional view illustrations of a dental implant installation assembly, constructed and operative in accordance with a further preferred embodiment of the present invention; 
         FIGS. 8A, 8B and 8C  are simplified schematic respective front, cross-sectional and top view illustrations of an implantation tool useful in a dental implant installation assembly of the type shown in  FIGS. 7A-7C ; 
         FIG. 9  is a simplified top view illustration of a dental implant useful in a dental implant installation assembly of the type shown in  FIGS. 7A-7C , showing forces acting thereon; 
         FIG. 10  is a simplified schematic illustration of an alternative embodiment of an implantation tool, constructed and operative in accordance with still another preferred embodiment of the present invention; 
         FIGS. 11A and 11B  are respectively a simplified pictorial illustration and cross-section thereof of a system for installation of a dental implant using a dental implant installation assembly constructed and operative in accordance with a preferred embodiment of the present invention; 
         FIGS. 12A, 12B and 12C  are respectively a first simplified pictorial illustration, a cross-section thereof and a second simplified pictorial illustration of a system for disassembling a dental implant installation assembly following insertion of a dental implant, constructed and operative in accordance with a preferred embodiment of the present invention; and 
         FIG. 13  is a flow chart illustrating a method for coating a titanium element. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference is now made to  FIGS. 1A-1D , which are simplified schematic respective isometric, front, cross-sectional and exploded view illustrations of a dental implant installation assembly, constructed and operative in accordance with a preferred embodiment of the present invention. 
     As seen in  FIGS. 1A-1D , there is provided a dental implant installation assembly  100  preferably including a dental implant body  102  and an implantation tool  104  mounted on dental implant body  102 . Installation assembly  100  further preferably includes a screw  106  connecting dental implant body  102  to implantation tool  104 . Dental implant body  102  may be any dental implant suitable for insertion into the jaw bone of a patient by way of application of a torque to the dental implant body. Particularly preferably, dental implant body  102  may be formed by zirconia. Zirconia dental implants tend to be susceptible to damage due to fractures or deformation occurring as a result of application of a torque thereto during installation. It is a particular feature of a preferred embodiment of the present invention that the use of implantation tool  104  to install dental implant body  102  allows the application of a sufficiently strong torque to dental implant body  102  to ensure secure installation thereof whilst preventing damage to dental implant body  102 , by distributing the installation torque over the dental implant body in a manner to be detailed henceforth. 
     Dental implant body  102  preferably comprises a head portion  110  and a threaded base portion  112  extending therefrom. As seen most clearly in  FIGS. 1D-2C , head portion  110  preferably has a generally annular flat uppermost surface  114 , a chamfered outwardly sloping segment  116  located beneath top surface  114  and a chamfered inwardly sloping segment  118  located beneath chamfered outwardly sloping segment  116  and atop of threaded base portion  112 . 
     Dental implant body  102  preferably includes an opening and at least a first surface peripheral to the opening, here embodied, by way of example, as a hexagonal opening  120  preferably centrally formed in head portion  110  and having uppermost surface  114  peripheral thereto. Uppermost surface  114  preferably forms a flat ring circumferentially surrounding an upper rim  122  of opening  120  and generally level therewith, as seen most clearly in  FIGS. 2B and 2C . Opening  120  is here shown to have a generally hexagonal configuration, the apices of the hexagon lying along the locus of the inner circumference of the ring formed by surface  114 , as seen in  FIG. 2C . An inner threaded bore  124  preferably extends beneath opening  120  within base portion  112 , which inner threaded bore  124  is preferably adapted for the receipt of screw  106  therein. 
     Implantation tool  104  preferably has a lower portion  130  adapted for insertion in opening  120  and at least a second surface peripheral to portion  130 , here embodied, by way of example, as a generally flat second surface  132 , from which second surface  132  lower portion  130  preferably extends, as seen most clearly in  FIGS. 3A-3C . Lower portion  130  is preferably embodied as a hexagonal protrusion compatible for insertion in hexagonal opening  120 . 
     An inner bore  134  is preferably formed within a generally cylindrical body  136  of implantation tool  104  for receipt of screw  106  therein. Inner bore  134  preferably has a generally hexagonal entrance  137  located at a top end of cylindrical body  136 . When installation assembly  100  is in an assembled state, protrusion  130  of implantation tool  104  is inserted in opening  120  of implant body  102 . Implantation tool  104  is secured to implant body  102  by insertion of screw  106  in inner bore  134  of implantation tool  104  and subsequent screwing of screw  106  into threaded bore  124 . 
     Upon assembly of installation assembly  100 , at least first and second surfaces of implant body  102  and implantation tool  104  respectively are in mutual contact. Here, by way of example and as seen most clearly at enlargement  138  in  FIG. 1C , first uppermost surface  114  of implant body  102  is engaged and in contact with second surface  132  of implantation tool  104  when installation assembly  100  is in its assembled state. It is appreciated that implantation tool  104  is thus engaged with implant body  102  at at least two spatially distributed contact regions, namely the contact region formed at the interface between lower portion  130  and opening  120  and the contact region formed at the interface between first uppermost surface  114  and second surface  132 . 
     During installation of dental implant body  102 , a torque is exerted by implantation tool  104  on dental implant body  102 . The torque exerted by implantation tool  104  on dental implant body  102  may he originally applied to implantation tool  104  manually or electronically, by hand and/or via tools, as will be explained in greater detail with reference to  FIGS. 11-12C  henceforth. 
     Due to the configuration of the multiple, spatially distributed contact regions between the implantation tool  104  and the dental implant  102 , the torque applied by implantation tool  104  on dental implant body  102  is distributed over dental implant body  102  at least as a torsion torque at opening  120  and a friction torque at first uppermost surface  114 . 
     The application of the torsion and friction torques may he best understood by reference to  FIG. 2C . As seen in  FIG. 2C , a torsion torque creating an inner radial force denoted by a first set of arrows  140 , is preferably exerted by protrusion  130  at hexagonal opening  120 . The radial forces  140  are primarily exerted in the region of the apices of hexagonal opening  120  due to contact thereat between the lumen of the hexagonal opening  120  and the corresponding apices of hexagonal protrusion  130 . In addition, a friction torque, creating a force denoted by a second arrow  142 , is preferably exerted by second surface  132  on first surface  114 , as indicated at the hatched region of implant body  102 . It is appreciated that an additional moment is exerted by screw  106  at the region of contact thereof with inner threaded bore  124 . 
     As appreciated from consideration of  FIG. 2C , the torsion torque and friction torque are complementary and create moments in the same direction, such that both the torsion and friction torques contribute to the overall torque applied to the implant body  102 . Due to the spatial distribution of the torsion torque and friction torque, only a portion of the torque exerted by the implantation tool  104  is applied at the hexagonal opening  120 . This distribution of the torque applied to the dental implant body  102  and consequent reduction of the torque applied to the dental implant body  102  at the hexagonal opening  120 , allows a greater total torque to be applied to the dental implant body  102  by the implantation holder  104 . In the absence of the implantation holder  104 , should an installation torque be applied directly to the implant body, only a weaker force may be applied to the implant body due to the likelihood of damage thereto. 
     Implantation tool  104  may be formed by Titanium. As is well known in the art, titanium tools tend to leave marks on zirconia implants, which marks may be aesthetically displeasing. It is a further particular feature of a preferred embodiment of the present invention that implantation tool  104  may be coated by a layer of titanium oxide, as seen most clearly at an enlargement  160  in  FIG. 3B , showing a highly magnified schematic representation of a titanium oxide layer  162  formed on a titanium surface  164 . 
     The titanium oxide coating  162  is preferably integrally bonded to the titanium surface  164  of implantation tool  104  by way of oxidation of the titanium substrate  164  provided by the tool itself and is therefore strongly adhered thereto. The titanium oxide coating  162  may be formed by electrolysis, in a manner detailed below with reference to  FIG. 13 . The titanium oxide coating preferably does not leave marks on zirconia and therefore leads to an improved aesthetic appearance of the installed zirconia implant body  102 . Furthermore, the titanium oxide coating is preferably harder than the original titanium comprising tool  104  and therefore more stable. 
     Reference is now made to  FIGS. 4A-4C , which are simplified schematic respective isometric, front and cross-sectional view illustrations of a dental implant installation assembly, constructed and operative in accordance with another preferred embodiment of the present invention. 
     As seen in  FIGS. 4A-4C , there is provided a dental implant installation assembly  400  preferably including dental implant body  102  and an implantation tool  404  mounted on dental implant body  102 . Installation assembly  400  further preferably includes screw  106  connecting dental implant body  102  to implantation tool  404 . It is a particular feature of a preferred embodiment of the present invention that the use of implantation tool  404  to install dental implant body  102  allows the application of a sufficiently strong torque to dental implant body  102  to ensure secure installation thereof whilst preventing damage to dental implant body  102 , by distributing the installation torque over the dental implant body in a manner to be detailed henceforth. 
     Dental implant installation assembly  400  may generally resemble dental implant installation assembly  100  in relevant aspects thereof, with the exception of the structure of implantation tool  404 , seen most clearly in  FIGS. 5A-5C . Implantation tool  404  preferably has a lower portion  430  adapted for insertion in opening  120  of implant body  102  and generally resembling lower protrusion  1 . 30  of implantation tool  104 . Lower portion  430  is preferably embodied as a hexagonal protrusion compatible for insertion in hexagonal opening  120 . 
     Implantation tool  404  further preferably includes at least a second surface peripheral to portion  430 , here embodied, by way of example, as a beveled surface  432  angled so as to lie flush with chamfered outwardly sloping segment  116  when installation assembly  400  is in its assembled state, as seen most clearly in  FIG. 4C . The base of implantation tool  404  thus may have a truncated cone configuration formed by beveled side walls  432  and a flat apex  433 . Beveled side walls  432  may be angled at approximately  45 °, although it is appreciated that other angular configurations of beveled side walls  432  are also possible. 
     An inner bore  434  is preferably formed within a generally cylindrical body  436  of implantation tool  404  for receipt of screw  106  therein. Inner bore  434  preferably has a generally hexagonal entrance  437  located at a top end of cylindrical body  436 . When installation assembly  400  is in an assembled state, protrusion  430  of implantation tool  404  is inserted in opening  120  of implant body  102 . Implantation tool  404  is secured to implant body  102  by insertion of screw  106  in inner bore  434  of implantation tool  404  and subsequent screwing of screw  106  into threaded bore  124 . 
     Upon assembly of installation assembly  400 , at least first and second surfaces of implant body  102  and implantation tool  404  respectively are in mutual contact. Here, by way of example and as seen most clearly at enlargement  438  in  FIG. 4C , chamfered outwardly sloping surface  116  of implant body  102  is engaged and in contact with second sloping surface  432  of implantation tool  404  when installation assembly  400  is in its assembled state. It is appreciated that implantation tool  404  is thus engaged with implant body  102  at at least two spatially distributed contact regions, namely the contact region formed at the interface between lower portion  430  and opening  120  and the contact region formed at the interface between surface  116  and beveled side walls  432 . 
     During installation of dental implant body  102 , a torque is exerted by implantation tool  404  on dental implant body  102 . The torque exerted by implantation tool  404  on dental implant body  102  may he originally applied to implantation tool  404  manually or electronically, by hand and/or via tools, as will be explained in greater detail with reference to  FIGS. 11-12C  henceforth. 
     Due to the configuration of the multiple, spatially distributed contact regions between the implantation tool  404  and the dental implant  102 , the torque applied by implantation tool  404  on dental implant body  102  is distributed over dental implant body  102  at least as a torsion torque at opening  120  and a friction torque at second outwardly sloping surface  116 . 
     The application of the torsion and friction torques may be best understood by reference to  FIG. 6 , which is a simplified top view illustration of forces acting on a dental implant in a dental implant installation assembly of the type shown in  FIGS. 4A-4C . 
     As seen in  FIG. 6 , an torsion torque is preferably exerted by protrusion  430  at hexagonal opening  120 , creating a radial force denoted by a first set of arrows  440 . The radial force  440  is primarily exerted in the region of the apices of hexagonal opening  120  due to contact thereat between the hexagonal lumen of hexagonal opening  120  and the corresponding apices of hexagonal protrusion  430 . In addition, a friction torque, creating a force denoted by a second arrow  442 , is preferably exerted by second surface  432  on first surface  116 , as indicated by the hatched region of implant body  102 . It is appreciated that an additional moment is exerted by screw  106  at the region of contact thereof with inner threaded bore  124 . 
     Additionally, a set of internally directed radial forces, denoted by a third set of arrows  444 , is preferably exerted normal to a longitudinal axis of implant body  102  by second surface  432 . It is appreciated that the internally directed radial forces denoted by arrows  444  correspond to the horizontal vector component of the force exerted by angled side wails  432  on first surface  116 . it is a particular feature of this embodiment of the present invention that internally directed radial forces  444  are exerted by implantation tool  404  on implant body  102  in a direction opposing the externally directed radial forces  440  at hexagonal opening  120 , thereby further stabilizing implant body  102  against fracture and/or deformation. 
     As appreciated from consideration of  FIG. 6 , the inner torsion torque and friction torque are complementary and create moments in the same direction, such that both the inner torsion and friction torques contribute to the overall torque applied to the implant body  102 . However, due to the spatial distribution of the inner torsion torque and friction torque, only a portion of the torque exerted by the implantation tool  404  is applied at the hexagonal opening  120 . Additionally, that portion of the torque applied at hexagonal opening  120  is further counteracted by internally directed radial forces  444 . This distribution of the torque applied to the dental implant body  102  and consequent reduction of the torque applied to the dental implant body  102  at the hexagonal opening  120 , allows a greater total torque to be applied to the dental implant body  102  by the implantation holder  404 . In the absence of the implantation holder  404 , should an installation torque be applied directly to the implant body, only a weaker force may be applied to the implant body due to the likelihood of damage thereto. 
     Implantation tool  404  may be formed by Titanium. As is well known the art, titanium tools tend to leave marks on zirconia implants, which marks may be aesthetically displeasing. It is a particular feature of a preferred embodiment of the present invention that implantation tool  404  may be coated with a layer of titanium oxide, as seen most clearly at an enlargement  460  in  FIG. 5B , showing a highly magnified schematic representation of a titanium oxide layer  462  formed on a titanium surface  464 . 
     The titanium oxide coating  462  is preferably integrally bonded to the titanium surface  464  of implantation tool  404  by way of oxidation of the titanium substrate  464  provided by the tool surface itself and is therefore strongly adhered thereto. The titanium oxide coating  462  may be formed by electrolysis, in a manner detailed below with reference to  FIG. 13 . The titanium oxide coating preferably does not leave marks on zirconia and therefore leads to an improved aesthetic appearance of the installed zirconia implant body  102 . Furthermore, the titanium oxide coating is preferably harder than the original titanium comprising tool  404  and therefore more stable. 
     Reference is now made to  FIGS. 7A-7C , which are simplified schematic respective isometric, front and cross-sectional view illustrations of a &amp;Mai implant installation assembly, constructed and operative in accordance with yet another preferred embodiment of the present invention. 
     As seen in  FIGS. 7A-7C , there is provided a dental implant installation assembly  700  preferably including dental implant body  102  and an implantation tool  704  mounted on dental implant body  102 . Installation assembly  700  further preferably includes screw  106  connecting dental implant body  102  to implantation tool  704 . It is a particular feature of a preferred embodiment of the present invention that the use of implantation tool  704  to install dental implant body  102  allows the application of a sufficiently strong torque to dental implant body  102  to ensure secure installation thereof whilst preventing damage to dental implant body  102 , by distributing the installation torque over the dental implant body in a manner to be detailed henceforth. 
     Dental implant installation assembly  700  may generally resemble dental implant installation assemblies  100  and  400  in relevant aspects, with the exception of the structure of implantation tool  704 , seen most clearly in  FIGS 8A-8C . Implantation tool  704  preferably has a lower portion  730  adapted for insertion in opening  120  of implant body  102  and generally resembling lower protrusion  130  of implantation tool  104 . Lower portion  730  is preferably embodied as a hexagonal protrusion compatible for insertion in hexagonal opening  120 . 
     Implantation tool  704  further preferably includes at least a second surface peripheral to portion  730 , here embodied, by way of example, as a first flat surface  732  configured so as to lie flush with uppermost surface  114  and a second beveled surface  733  configured so as to lie flush with chamfered outwardly sloping segment  116  when installation assembly  700  is in its assembled state, as seen most clearly in  FIG. 7C . The base of implantation tool  704  thus may have a truncated cone configuration formed by beveled side walls  733  and flat apex  732 . It is a particular feature of this embodiment of the present invention that a part of the second surface peripheral to portion  730 , embodied herein as . beveled surface  733 , may be formed as a segment surface, as seen most clearly in  FIGS. 7A and 7B . The segmentation of beveled surface  733  imparts flexibility to beveled surface  733 . Such flexibility is advantageous in this embodiment of the present invention, since it facilitates simultaneous contact of multiple surfaces of implantation tool  704  with implant body  102 , as will be detailed below. Beveled surface  733  may be angled at approximately  45 ° , although it is appreciated that other angular configurations of beveled surface  733  are also possible. 
     An inner bore  734  is preferably formed within a generally cylindrical body  736  of implantation tool  704  for receipt of screw  106  therein. Inner bore  734  preferably has a generally hexagonal entrance  737  located at a top end of cylindrical body  736 . When installation assembly  700  is in an assembled state, protrusion  730  of implantation tool  704  is inserted in opening  120  of implant body  102 . Implantation tool  704  is secured to implant body  102  by insertion of screw  106  in inner bore  734  of implantation tool  704  and subsequent screwing of screw  106  into threaded bore  124 . 
     Upon assembly of installation assembly  700 , at least first and second surfaces of implant body  102  and implantation tool  704  respectively are in mutual contact. Here, by way of example and as seen most clearly at enlargement  738  in  FIG. 7C , uppermost surface  114  is engaged and in contact with flat apex  732  and chamfered outwardly sloping segment  116  of implant body  102  is engaged and in contact with beveled surface  733  when installation assembly  700  is in its assembled state. It is appreciated that implantation tool  704  is thus engaged with implant body  102  three spatially distributed contact regions, namely the contact region formed at the interface between lower portion  730  and opening  120 , the contact region formed at the interface between first uppermost surface  114  and flat apex  732  and the contact region formed at the interface between second sloping surface  116  and beveled surface  733 . 
     During installation of dental implant body  102 , a torque is exerted by implantation tool  704  on dental implant body  102 . The torque exerted by implantation tool  704  on dental implant body  102  may be originally applied to implantation tool  704  manually or electronically, by hand and/or via tools, as will be explained in greater detail with reference to  FIGS. 11-12C  henceforth. 
     Due to the configuration of the multiple, spatially distributed contact regions between the implantation tool  704  and the dental implant  102 , the torque applied by implantation tool  704  on dental implant body  102  is distributed over dental implant body  102  at least as a torsion torque at opening  120  and a friction torque at first and second surfaces  114  and  116 . 
     The application of the torsion and friction torques may be best understood by reference to  FIG. 9 , which is a simplified top view illustration of forces acting on a dental implant in a dental implant installation assembly of the type shown in  FIGS. 7A-7C . 
     As seen in  FIG. 9 , a torsion torque is preferably exerted by protrusion  730  at hexagonal opening  120 , creating radial forces denoted by a first set of arrows  740 . The radial forces  740  are primarily exerted in the region of the apices of hexagonal opening  120  due to contact thereat between the hexagonal lumen of hexagonal opening  120  and the corresponding apices of hexagonal protrusion  730 . in addition, a first friction torque, creating a force denoted by a second arrow  742 , is preferably exerted by first surface  732  on uppermost surface  114 , as indicated by the hatched region of implant body  102  and a second friction force, denoted by a third arrow  743 , is preferably exerted by beveled surface  733  on chamfered surface  116 . It is appreciated that an additional moment is exerted by screw  106  at the region of contact thereof with inner threaded bore  124 . 
     Additionally, a set of internally directed radial forces, denoted by a fourth arrow  744 , is preferably exerted normal to a longitudinal axis of implant body  102  by beveled surface  733 . It is appreciated that the internally directed radial forces denoted by arrows  744  correspond to the horizontal vector component of the force exerted by angled surface  733  on first surface  116 . It is a particular feature of this embodiment of the present invention that internally directed radial forces  744  are exerted by implantation tool  704  on implant body  102  in a direction opposing the externally directed radial forces  740  at hexagonal opening  120 , thereby further stabilizing implant body  102  against fracture and/or deformation. 
     As appreciated from consideration of  FIG. 9 , the torsion torque and two friction torques are complementary and create moments in the same direction, such that the torsion and friction torques contribute to the overall torque applied to the implant body  102 . However, due to the spatial distribution of the torsion torque and friction torques, only a portion of the torque exerted by the implantation tool  704  is applied at the hexagonal opening  120 . Additionally, that portion of the torque applied at hexagonal opening  120  is further counteracted by internally directed radial forces  744 . 
     This distribution of the torque applied to the dental implant body  102  and consequent reduction of the torque applied to the dental implant body  102  at the hexagonal opening  120 , allows a greater total torque to be applied to the dental implant body  102  by the implantation holder  704 . In the absence of the implantation holder  704 , should an installation torque be applied directly to the implant body, only a weaker force may be applied to the implant body due to the likelihood of damage thereto. 
     Implantation tool  704  may be formed by Titanium. As is well known in the art, titanium tools tend to leave marks on zirconia implants, which marks may be aesthetically displeasing. Tt is a particular feature of a preferred embodiment of the present invention that implantation tool  704  may be coated with a layer of titanium oxide, as seen most clearly at an enlargement  760  in  FIG. 8B , showing a highly magnified schematic representation of a titanium oxide layer  762  formed on a titanium surface  764 . 
     The titanium oxide coating  762  is preferably integrally bonded to the titanium surface  764  of implantation tool  704  by way of oxidation of the titanium substrate  764  provided by the tool itself and is therefore strongly adhered thereto. The titanium oxide coating  762  may be formed by electrolysis, in a manner detailed below with reference to  FIG. 13 . The titanium oxide coating preferably does not leave marks on zirconia and therefore leads to an improved aesthetic appearance of the installed zirconia implant body  102 . Furthermore, the titanium oxide coating is preferably harder than the original titanium comprising tool  704  and therefore more stable. 
     The allowance of the exertion of an increased installation torque on the dental implant body of the present invention as a result of the use of the implantation tool of the present invention, without breaking the dental implant body, is evidenced by experimental data collected by the present inventors. 
     In order to model the dental implantation assembly of the present invention, dental implant bodies generally resembling dental implant body  102  were connected to implantation tools of types generally resembling each one of implantation tools  104 ,  404  and  704  respectively. The connecting screw  106  was tightened with a torque of 30 N/cm. The implant bodies were held in a fixing device in a manner so as to simulate insertion into the bone of a patient in a manner allowing the application of an ascending torque. A key was inserted into the hexagonal entrance of the implantation tool with a digital torque gauge connected thereto, in order to measure the torque exerted thereby. For each of the three embodiments of implantation tools  104 ,  404  and  704  an ascending torque was gradually applied and the torque at which the implant body broke, termed the breaking torque, was measured. 24 or 25 samples were investigated for each case. 
     The average, breaking torques when implementation tools of types resembling implantation tools  104 ,  404  and  704  were used were found to be 145.1 N/cm, 141. N/cm and 142 N/cm respectively. For comparative purposes, the same experiment was repeated in the absence of an implantation tool for 50 samples and an average breaking torque of 43.9 N/cm was measured. 
     It is thus appreciated, that the use of an implantation tool in accordance with the presence invention allows the torque applied to the dental implant body to be increased by more than 300% without breaking the dental implant body. Furthermore, since a typical installation torque is approximately 50-60 N/cm, it is understood that without the use of an implantation tool constructed and operative in accordance with the present invention, the implant body itself is not strong enough to withstand installation. Data collected in the case of use of implantation tool  404  was found to exhibit a larger distribution and include lower values, possibly indicating greater risk of fracture for this embodiment in comparison to the other two embodiments. No significant differences were found between data obtained for uncoated and titanium oxide coated implantation tools, validating that the coating of the implantation tool in order to prevent aesthetic damage to the implant body does not impede the efficacy of the tool. 
     It is appreciated that although in the foregoing examples, opening  120  in implant  102  and corresponding protrusions  130 ,  430  and  730  of implantation tools  104 ,  404  and  704  respectively have been described and shown as being hexagonally shaped, this is by way of example only. The opening in the implant body and correspondingly shaped protrusion of the implantation tools of the present invention may be configured in a variety of other suitable geometrical shapes, as will be readily appreciated by one skilled in the art. By way of example only, the opening and protrusion may be triangularly shaped, as illustrated in the case of a generally triangular opening  1020  and a corresponding protrusion  1030  shown in  FIG. 10 . 
     It is additionally appreciated that the particular configurations of contacting first and second surfaces of the implant body and implantation tool are illustrative only and that first and second contacting surfaces may have a variety of suitable configurations, including non-planar and/or non-linear portions, which portions may be continuous or segmented. 
     It is further appreciated that although in the foregoing examples, head cavities  137 ,  437  and  737  of implantation tools  104 ,  404  and  704  respectively are shown to be hexagonally shaped, the head cavity of an implantation tool of the present invention may be configured to have other suitable geometrical shapes. 
     Reference is now made to  FIGS. 11A and 11B , which are respectively a simplified pictorial illustration and cross-section thereof of a system for installation of a dental implant using a dental implant installation assembly constructed and operative in accordance with a preferred embodiment of the present invention. 
     As seen in  FIGS. 11A and 11B , dental implant body  102  may be installed by application of a torque to an implantation tool, such as implantation tool  704  illustrated herein. It is appreciated that although the installation system of  FIGS. 11A and 11B  is shown herein with respect to implantation tool  704  of installation assembly  700 , the installation system is applicable to any one of the installation assemblies of the present invention. 
     The installation torque may be applied to implantation tool  704  by means of a torque ratchet  1100  connected to a key  1102 , which key  1102  may slot into hexagonal head cavity  737  of implantation tool  704 , as seen most clearly in  FIG. 11B . It is appreciated, however, that the use of torque ratchet  1100  and key  1102  may not be necessary and, in some cases, a user may manually twist implantation tool  704  so as to install implant body  102 . An installation torque of approximately 50-60 N/cm may be applied. It is appreciated that a head portion of key  1102  is not limited to being hexagonal and may assume any shape compatible with the corresponding head cavity of the implantation tool. 
     It is thus appreciated that during installation of implant body  102  a torque is preferably directly applied by a user, such as a dentist, to the implantation tool and preferably only indirectly applied by the user to the implantation body  102 , by way of the implantation tool. 
     It is understood that in the installation system of  FIGS. 11A  and.  11 B, implantation assembly  700  is shown to be pre-assembled, with screw  106  in place and implant body  102  already tightened to implantation tool  704 . It is appreciated, however, that in some cases implantation assembly  700  may require full or partial pre-assembly by a user prior to installation of the implant body in a patient. In such a case, screw  106  may be inserted/and or tightened by a user using standard tools, as are well known in the art. The tightening torque to be applied to screw  106  is in accordance with design requirements. 
     It is appreciated that following implantation of dental implant body  102  in the jaw of a patient, the attached implantation tool must be extracted therefrom. An exemplary system for disassembling a dental implant installation assembly following implantation of a dental implant is shown in  FIGS. 12A-12C . 
     As seen in  FIGS. 12A-12C , in order to disassemble a dental implant installation assembly of the present invention, such as assembly  700  illustrated herein, screw  106  may be extracted from the assembly using torque ratchet  1100  to manipulate a screw-driver  1204 . In order to prevent displacement of implant body  102  during removal of screw  106 , implant body  102  may be held in place by an anti-rotation tool  1206 . Anti-rotation tool  1206  may have a post-like head  1208  adapted for entry into one of a multiplicity of holes  1210  formed on an exterior surface of the implantation tool, so as to prevent rotation of the implantation tool during removal of the inner screw  106 . Anti-rotation tool  1206  may also have a second spanner-shaped head  1212 ., which spanner-shaped head  1212  may alternatively be used to secure the implantation tool in place during removal of the screw  106 . 
     As seen in  FIG. 12B , screw-driver  1204  is progressively screwed into screw  106 , so as to completely remove screw  106  from assembly  700 . Once screw  106  is removed from assembly  700 , as seen in  FIG. 12C , the implantation tool, such as tool  704 , simply falls away from or may be manually removed from dental implant body  102 . It is appreciated that the implantation tool of the present invention may be a single-use tool which is disposed subsequent to use. Alternatively, the implantation tool of the present invention may be suitable for multiple, repeated use. 
     As previously mentioned, the present invention is particularly well-suited for use with zirconia implants, which zirconia implants are more vulnerable to damage during implantation than comparable titanium implants. hi order to prevent scratching of the zirconia implant body by a titanium implantation tool, the titanium implantation tool of the present invention is preferably coated with a layer of titanium oxide, such as layers  162 ,  462  and  762  illustrated in  FIGS. 3, 5 and 8  respectively. The titanium oxide layer may be formed on the implant holder of the present invention by plasma electrolytic oxidation, in accordance with a process illustrated in  FIG. 13 . 
     Reference is now made to  FIG. 13 , which is a flow chart illustrating a method for coating a titanium element. 
     As seen in  FIG. 13 , a method  1300  for coating a Mum-comprising element provided. The method preferably includes providing an element comprising titanium, immersing the element in an electrolyte, providing a cathode in the electrolyte and applying a voltage between the cathode and the titanium element, a titanium oxide coating being formed thereby on the element. 
     It is appreciated that although the titanium oxide coating and associated method is described herein with reference to the coating of implantation tools  104 ,  404  and  704 , a titanium oxide coating in accordance with the present invention may be applied to any suitable titanium-comprising element, in order to allow the clean use of such elements on zirconia or other surfaces without marking. As explained above, in the absence of such a titanium oxide coating, titanium elements may leave aesthetically displeasing marks on zirconia or other surfaces with which they come into contact. Titanium-comprising elements that may benefit from the titanium oxide coating of the present invention include titanium-comprising dental tools, such as the implantation tools described herein above, titanium-comprising connecting elements, such as screw  106  described herein above as well as titanium-comprising accessories and prosthetics, by way of example only. It is further appreciated that such elements may be disposable or non-disposable elements and may be formed by titanium only or may comprise titanium alloys, as will be detailed below. 
     It is additionally appreciated that the particular steps of method  1300  described hereinbelow are exemplary only and may be supplemented or substituted as will be apparent to one skilled in the art. 
     The titanium comprising the element, such as a dental tool, may be a commercially pure, unalloyed titanium, such as ASTM Grade 1, Grade 2, Grade 3 or Grade 4 titanium. ASTM Grade 1 titanium contains a maximum of 0.08% C, 0.03% N, 0.18% 0 0.20% Fe and 0.015% H by weight. ASTM Grade 2 titanium contains a maximum of 0.08% C, 0.03% N, 0.25% 0 0.30% Fe and 0,015% H by weight. ASTM Grade 3 titanium contains a maximum of 0.08% C, 0.05% N, 0.35% 0 0.30% Fe and 0.015% H by weight. ASTM Grade 4 titanium contains a maximum of 0.08% C, 0.05% N, 0.40% 0 0.50% Fe and 0.015% H by weight. 
     Alternatively, the titanium comprising the element, such as a dental tool, may be a titanium alloy. For example, the titanium alloy may be Ti-6Al-7Nb available from RMI Titanium Company of Niles, OH, USA. This alloy contains a maximum of 0.08% C, 0.05% N, 0.20% 0, 0,25% Fe, 0.50% Ta, and 0.009 H, as well as 5.5-6.5% Al and 6.5-7.5% Nb by weight. The alloy may also be ASTM Grade 5 titanium sold as Ti-6Al-4V by RMI Titanium Company. This alloy contains 0.08% C, 0.25% Fe, 0.05% N, 0,20% C) and 0.015% H, as well as 5.50-6.75% Al and 3.5-4.5% V by weight. Alternatively, the alloy may be ASTM Grade 23 titanium sold as Ti-6Al-4V ELI (extra low interstitials) by RMI Titanium Company. This alloy contains 0.08% C, 0.25% Fe, 0.03% N, 0.13% 0 and 0.0125% H, as well as 5.5-6.5% Al and 3.5-4.5% V by weight. 
     As seen at a first step  1302  in  FIG. 13 , the titanium element may be initially cleaned prior to oxidation thereof. The cleaning may include a degreasing step. The degreasing may be carried out with a detergent formed from an alkali, such as sodium hydroxide or potassium hydroxide. Preferably, the pH of the alkali is about 10. Alternatively, the degreasing may be canned out with an organic solvent. Preferred organic solvents include hexane and isopropanol. 
     As seen at a second step  1304 , the titanium element may also be subject to surface etching prior to oxidation thereof. The etching may be carried out in a solution containing an oxidizer such as nitric acid, hydrogen peroxide or persulfate salt and a titanium depassivating agent, such as hydrogen fluoride, hexafluorosilicic acid (H 2 SiF 6 ) or tetrafluoroboric acid (HBF 4 ). 
     it is appreciated that although in method  1300  cleaning step  1302  is shown to precede surface etching step  1304 , this is not necessarily the case. 
     Following optional cleaning and etching steps  1302  and  1304 , the titanium element maybe immersed in an electrolyte bath containing a cathode, as seen at a third step  1306 . The electrolyte is preferably an aqueous acidic electrolyte. The electrolyte preferably contains between 0.1-1 mol/L of sulfuric acid, more preferably 0.5 mol/L. The electrolyte also preferably contains between 0.1-1 mol/L of phosphoric acid, more preferably 0.5 mol/L. The electrolyte optionally contains up to 1 mol/L hydrogen peroxide, preferably 0.5 mol/L. In an alternative embodiment, the electrolyte is an aqueous alkaline electrolyte. In a further alternative embodiment, the electrolyte is a non-aqueous electrolyte. 
     The cathode is preferably a stainless steel cathode. The reactions that occur at the cathode are: 
       4H + +4 e   − →2H 2  
 
       H 2 O 2 +2H + +2 e   − →2H 2 O
 
     The reaction that occurs at the tool, which functions as the anode, is: 
       Ti+2H 2 O→TiO 2 +4H + +4 e   − 
 
     As seen at fourth step  1308 , a voltage suitable for plasma electrolytic oxidation is preferably applied. The voltage applied between the electrodes, namely the titanium element and cathode, is preferably in the range of 180-250 V, preferably 200 V. The current density ranges from 0.1-1 A/cm2, preferably 0.2 A/cm2. The voltage may be applied in AC or DC mode, preferably DC mode. 
     Due to the high voltages, the initial titanium oxide layer formed on the surface of the titanium element breaks down, initiating high temperature plasma processes resulting in micro--arc discharges within the layer. The result is a thick layer of mainly crystalline titanium oxide, as shown at a fifth step  1310 . The titanium oxide is predominantly in the anatase polymorphic form. Some of the titanium oxide may be in the rutile form. 
     Since the titanium oxide layer is formed from the titanium element itself and not deposited onto the element, the adhesion between the titanium oxide layer and the element surface is high. Preferably, the adhesion strength ranges from 15 to 40 MPa. The formed titanium oxide layer is preferably harder than titanium or amorphous titanium dioxide. The hardness of the titanium oxide layer is preferably lower than that of zirconia. Preferably, the hardness ranges from 5.5-6 on the Mohs scale. 
     It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly claimed hereinbelow. Rather, the scope of the invention includes various combinations and subcombinations of the features described hereinabove as well as modifications and variations thereof as would occur to persons skilled in the art upon reading the forgoing description with reference to the drawings and which are not in the prior art.