Abstract:
An implant including a bone fixture configured to anchor to bone of a recipient, and a structural component configured to be connected to the bone fixture and connect a functional component of the implant to the bone fixture, wherein at least one of the bone fixture or the structural component includes a deformable element configured to deform to form an anti-microbial seal between the bone fixture and the structural component, and the at least one deformable element and the respective at least one bone fixture or structural component form a monolithic structure.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation application of International Patent Application No. PCT/AU2010/000401, filed on Apr. 9, 2010, designating Goran Bjorn of Sweden and Dr. Marcus Andersson, also of Sweden, as inventors, which claims priority to Australian Provisional Patent Application No. 2009903789 entitled “Implant Device” filed on 13 Aug. 2009, and Australian Provisional Patent Application No. 2009905020 entitled “Implant Device” filed on 14 Oct. 2009, the entire content of each of these applications being hereby incorporated by reference herein in their entirety. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates generally to bone conduction devices, and more particularly, to infection prevention measures associated with percutaneous bone conduction devices. 
     2. Related Art 
     Bone-anchored medical implant systems are used to connect or fixate hearing devices to a recipient, directly to the bone or skull of the recipient. Some applications include hearing implants such as bone conduction devices marketed by Cochlear Bone Anchored Solutions AB in Sweden. Such bone conduction devices sometimes comprise, in the case of percutaneous bone conductions devices as is shown by way of example in  FIG. 27   d  in black-box format, an external, removable unit  2759  including a vibrator  2761  which transforms sound into mechanical vibrations. Percutaneous bone conductions devices conduct those mechanical vibrations via an abutment  2763  and a bone fixture  2765  of the implant, into the bone of the skull. Passive transcutaneous bone conduction devices conduct those mechanical vibrations through skin of the recipient to an implantable component which includes a bone fixture. The vibrations are transmitted mechanically via the skull bone and thereafter to the inner ear of a person with impaired hearing and allows for the hearing organ to register the sound. A hearing device of the bone conduction device type typically includes an anchoring element or fixture, in the form of, for example, an implanted titanium screw, corresponding to the bone fixture, installed in the bone behind the external ear and the sound is transmitted via the skull bone to the cochlea (inner ear), irrespective of any disease, injury or other dysfunction of the middle ear. In percutaneous bone conduction or anchoring arrangements, the skin is penetrated, which makes the vibratory transmission very efficient. This arrangement can also be used in connection with facial prostheses, such as, for example, some of those marketed by Cochlear Limited, Australia. 
     The implants which are used with percutaneous bone conduction devices are sometimes provided in two pieces. One piece comprises the screw-shaped anchoring element (fixture or anchor) and the other piece comprises the abutment, which penetrates the skin. This two-piece design, in many exemplary embodiments, allows the surgical implantation to be carried out as a two-step procedure. In the first step of implanting such a two-pieced design, the fixture is inserted and maintained unloaded during a healing period of some months or so. After this healing period the second step of the surgical procedure, i.e. the connection of the abutment by means of an abutment screw, is executed. The two-part design may allow for the implants to be up-graded, if desirable, without removing the fixture or anchor. Furthermore, if the abutment is damaged, it can then be replaced without need of removal of the bone anchored screw or fixture. 
     A situation sometimes experienced with bone conduction devices in general, and percutaneous implant devices in particular, is the risk of infections and inflammation. This exists sometimes at the tissue-implant interface. The infections are a result of bacterial colonization at the area around the interface between the bone fixture and the abutment. This problem can be persistent and cause infections. Cleaning of the interface has utility, but even regular cleaning and disinfection is not always entirely successful. The risk of infections may also exist at the interface between separate components of totally implantable prostheses. 
     With respect to a percutaneous bone conduction device, the bacteria may enter the implant-tissue interface by two different routes—an external route on the external surface of the abutment, and an internal route which starts at the top of the abutment and travels via internal parts (screw connection) of the implant system and may exit at the abutment-fixture-soft tissue junction or interface. The external route is the most open route, but the bacteria may also reach the implant-tissue interface from the internal route, known as the internal micro-leakage pathway. 
     SUMMARY 
     Some aspects of the present invention are generally directed to an implant including a bone fixture configured to anchor to bone of a recipient, and a structural component configured to be connected to the bone fixture and connect a functional component of the implant to the bone fixture, wherein at least one of the bone fixture or the structural component includes a deformable element configured to deform to form an anti-microbial seal between the bone fixture and the structural component, and the at least one deformable element and the respective at least one bone fixture or structural component form a monolithic structure. 
     Some other aspects of the present invention are generally directed to an implant, comprising a bone fixture configured to anchor to bone of a recipient, a structural component configured to be connected to the bone fixture and connect a functional component of the implant to the bone fixture, and a screw configured to bolt the structural component to the bone fixture, wherein the implant includes an anti-microbial seal between the structural component and the screw. 
     Some other aspects of the present invention are generally directed to an implant, comprising, a bone fixture configured to anchor to bone of a recipient, and a structural component configured to be connected to the bone fixture and connect a functional component of the implant to the bone fixture, wherein at least one of the bone fixture or the structural component includes a deformable element configured to plastically deform to form an anti-microbial seal between the bone fixture and the structural component. 
     Some other aspects of the present invention are generally directed to a method of attaching an abutment to an implanted bone fixture to form a percutaneous implant, comprising positioning the abutment in contact with the implanted bone fixture, and applying a torque of about 15 Ncm or more to a component of the percutaneous implant threadably engaged with the implanted bone fixture, thereby driving the abutment towards the bone fixture via reaction against the implanted bone fixture, wherein the applied torque is sufficient to at least one of deform material of at least one of the bone fixture and the abutment to form an anti-microbial seal between the bone fixture and the abutment, or deform material of at least one of an abutment screw and the abutment to form an anti-microbial seal between the abutment screw and the abutment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention are described below with reference to the attached drawings, in which: 
       FIG.  1 —shows an example of a medical implant system to which various aspects of the present disclosure may be applied; 
       FIG.  2 —shows a cross section of the medical implant system of  FIG. 1 ; 
       FIG.  3 —shows a perspective view of the medical implant system of  FIG. 1 ; 
       FIG.  4 —shows a cross section exploded view of the components of the medical implant system of  FIG. 1 ; 
         FIG. 5   a —shows one embodiment of an abutment screw of one aspect of the disclosure; 
         FIG. 5   b —shows a cross section of the abutment screw of  FIG. 5A ; 
         FIG. 5   c —shows a close up view of the deformable element of  FIG. 5B ; 
       FIG.  6 —shows a cross section of the abutment screw of  FIG. 5A  in an abutment; 
       FIG.  7 —shows a close-up cross section view of a seal provided between the abutment screw of  FIG. 5A  and the abutment; 
       FIG.  8 —shows a cross section of an alternative embodiment of the abutment screw of  FIG. 5A ; 
         FIG. 9   a —shows a cross section of yet a further alternative of the abutment screw of  FIG. 5A ; 
         FIG. 9   b —shows a perspective view of the abutment screw of  FIG. 9A ; 
       FIG.  10 —shows a close-up cross section view of a seal provided between the abutment screw of  FIG. 9   a  and the abutment; 
       FIG.  11 —shows a perspective view of one embodiment of an abutment; 
       FIG.  12 —shows a cross section of the abutment of  FIG. 11 ; 
       FIG.  13 —shows a close-up view of a seal provided between the abutment screw and the abutment of  FIG. 11 ; 
       FIG.  14 —shows a cross section of one embodiment of a fixture; 
       FIG.  15 —shows a perspective view of one embodiment of an abutment for use with the fixture of  FIG. 14 ; 
       FIG.  16 —shows a perspective view of another embodiment of an abutment for use with the fixture of  FIG. 14 ; 
       FIG.  17 —shows a perspective view of yet another embodiment of an abutment for use with the fixture of  FIG. 14 ; 
       FIG.  18 —shows the abutment of any one of  FIGS. 15 to 17  in place in the fixture of  FIG. 14 ; 
       FIG.  19 —shows a close-up view of the seal provided by the arrangement of  FIG. 18 ; 
       FIG.  20 —shows a different embodiment of an abutment; 
       FIG.  21 —shows the abutment of  FIG. 20  engaging with a fixture; 
       FIG.  22 —shows a close-up of a seal provided by the arrangement of  FIG. 21 ; 
       FIG.  23 —shows an embodiment of a medical implant system with a seal provided between the abutment and the abutment screw; 
       FIG.  24 —shows another embodiment of a medical implant system with a seal provided between the abutment and the fixture; 
       FIG.  25 —shows another embodiment of a medical implant system with a seal provided between the abutment and the abutment screw as well as between the abutment and the fixture; 
         FIG. 26   a —shows a flow chart of a method of implanting a medical implant system; 
         FIG. 26   b —shows a specific example of the method of  FIG. 26   a;    
         FIG. 27   a —shows a cross section of the arrangement of the first step of the method of  FIG. 26   b;    
         FIG. 27   b —shows a cross section of the arrangement of the second step of the method of  FIG. 26   b ; and 
         FIG. 27   c —shows a cross section of the arrangement of the third step of the method of  FIG. 26B ; 
         FIG. 27   d —shows in black-box format a functional conceptual external removable unit of a percutaneous bone conduction device including a vibrator, along with an implant; 
       FIG.  28 —shows a close-up cross section view of a seal provided between the abutment screw of  FIG. 5   a  and the abutment in an alternate embodiment; 
       FIG.  29 —shows a close-up cross section view of a seal provided between the abutment screw of  FIG. 9   a  and the abutment in an alternate embodiment; 
         FIG. 30   a —shows a close-up view of a seal provided between the abutment screw and the abutment of  FIG. 11  in an alternate embodiment; 
         FIG. 30   b —shows a close-up view of the seal provided by the arrangement of  FIG. 18  in an alternate embodiment; 
       FIG.  31 —shows an alternate embodiment of a medical implant system with a seal provided between the abutment and the abutment screw; 
       FIG.  32 —shows another embodiment of a medical implant system with a seal provided between the abutment and the fixture; and 
       FIG.  33 —shows another embodiment of a medical implant system with a seal provided between the abutment and the abutment screw as well as between the abutment and the fixture. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a side view of a medical implant system  100 . The implant system has an abutment  10  that enables a hearing device to be coupled through a percutaneous connection to a bone anchoring device in the form of fixture  20 . Abutment  10  is connected to fixture  20 . Fixture  20  has a base collar  21  and screw threads  22 . In use, screw threads  22  is screwed into bone of the recipient (sometimes herein also referred to as the user) to fixate and retain fixture  20  to the user&#39;s skull. 
     As can be seen in  FIG. 2 , which shows a cross section view along the line A-A′ of  FIG. 1 , abutment  10  is connected to and retained to fixture  20  by abutment screw  30 . Abutment screw  30  has head  31 , a well  32  within the head  31  to receive an insertion tool or the like, and an apical outer screw threaded section  34  on an elongate main body  33 . In some examples, abutment screw  30  may be an M 1.8 titanium screw and the well  32  in head  31  may be a tubular hex configuration for receiving and cooperating with the insertion tool (not shown). The apical outer screw threaded section  34  engages with inner screw thread  23  of the fixture  20  upon turning of the insertion tool. 
       FIG. 3  shows a perspective view of the medical implant system  100 . In this view, the abutment interior  13  is visible, showing the abutment interior base  14 . Also visible in this view is abutment screw  30  with head  31  and hexagonal well  32 . The fixture  20  with base collar  21  and outer screw thread  22  is also visible. 
       FIG. 4  shows a cross section view of three constituent parts of the medical implant system  100 , with those parts separated from one another for clarity. There shown are abutment screw  30 , abutment  10  and fixture  20 . 
       FIG. 5A  shows an exemplary embodiment of abutment screw  30 . In particular, abutment screw head includes a base  35  which includes a deformable element in the form of a flange  36 , which is angled downwards and outwards away from the head at a flange angle of about 10 degrees (in one example), as is more clearly seen in  FIG. 5C .  FIGS. 5B and 5C  show a cross section view of the abutment screw  30  of  FIG. 5A . In these views, the deformable element in the form of the flange  36  is more clearly visible. 
     In one embodiment, the outer portion of the flange  36 , corresponding to at least part of the deformable element of the abutment screw  30 , has a flat portion  37  (see  FIG. 5C ) which, in use, rests on a corresponding contact surface, in this case, the abutment interior base  14  as shown in  FIG. 6 . The deformable element is able to deform to form a seal. In one example, when the abutment screw  30  is screwed down into the inner screw thread  23  of fixture  20 , flat portion  37  comes into contact with the corresponding contact surface or abutment interior base  14 . When the abutment screw  30  is screwed further downwards, the deformable element corresponding to flange  36  with flat portion  37  is pressed downwards (which may cause the edge to move outwards) against the corresponding contact surface or abutment interior base  14  and thereby deform to provide a seal between the abutment screw  30  and the corresponding contact surface, in this case abutment interior base  14 . In other words, the deformable element deforms a sufficient amount to provide a seal between the abutment screw  30  and the abutment  10 , upon tightening of the abutment screw  30 . 
     In other examples, the deformable element may deform upon application of downward pressure on the implant system or on a part thereof, such as on the screw head  31 . 
     In the various examples detailed herein and/or variations thereof, the type of deformation may be plastic, elastic or a combination of both. 
       FIG. 7  shows a close up view of this engagement between the abutment screw  30  and the abutment  10 , and in particular, shows how the deformation of the deformable element as flange  36  and the flat portion  37  is deformed and pressed into the surface of the abutment interior base  14 , to provide a seal. In some cases, the corresponding contact surface, in this case the abutment interior base  14 , may itself also deform slightly to further increase the seal formed therebetween. In the same vein,  FIG. 28  shows a close up view of engagement between the abutment screw  30  and the abutment  10  in an alternate embodiment, which depicts the flange  36  being pressed into the surface of the abutment interior base  14 , to provide a seal. As will be understood from  FIG. 28 , in this alternate embodiment, the corresponding contact surface, in this case the abutment interior base  14 , may itself deform slightly to further increase the seal formed therebetween. The degree of resulting deformation of the abutment screw and/or the abutment may vary between embodiments. In some embodiments, all or substantially all of the overall deformation may occur in the abutment screw  30 , while in some embodiments, all or substantially all of the deformation may occur in the abutment  10 , while in some embodiments, the amount of deformation may be more evenly distributed between these two components. 
     As the contact surface increases by the deformation of the flange  36  and/or the abutment interior base  14 , surface imperfections between the contacting surfaces might be compensated for, which reduces any gaps or holes for microbes (including fungi and bacteria) to pass through from the outside into the inside of the abutment. 
     This thereby provides a seal at the abutment and abutment screw interface, to reduce the risk of bacterial infection via the micro leakage pathway. 
     While the screw head  31  of abutment screw  30  may in some embodiments, have a well  32  as shown in  FIGS. 5A ,  5 B,  5 C and  6 , which may assist in providing the deformable element as flange  36 , in other embodiments, head  31  need not have a well. Further, the deformable element may be provided by any suitable structure, and may include the provision of an annular relief  38  above flange  36  to enhance the deformation, as shown in  FIG. 8 . 
     The screw head  31  of abutment screw  30  may in some embodiments, have a screw thread which may assist in providing the deformable element as flange  36  (not shown). 
     In another embodiment, as shown in a cross section view in  FIG. 9A , the deformable element may be provided on the base of the head  31  by way of an annular ring  39  extending about the outer edge of the abutment screw head base  35 .  FIG. 9B  shows a perspective view of this arrangement. As in the previous example, when abutment screw  30  is tightened into position, the deformable element in the form of annular ring  39 , is deformed so as to form a seal between the abutment screw  30  and the abutment  10 .  FIG. 10  shows a close up view of this seal formed by the deformation of the deformable element. Again, in some cases, the abutment interior base  14  may also be slightly deformed. In the same vein,  FIG. 29  shows an alternate embodiment where the deformable element is located again on the interior  14  abutment  10 , and element  39  presses into the abutment  10 , thereby forming a seal. in another embodiment, the deformable element in the form of the annular ring may be provided on the abutment itself. As may be seen from  FIG. 10  the deformable element may be a protrusion having a triangular cross-section or semi-circular cross section extending from a generally planar surface of a component of the medical implant. 
       FIG. 11  shows a perspective view of abutment  10  showing abutment interior  13  providing an abutment receiving well for receiving the abutment  10 , and abutment interior base  14 . Without abutment screw  30 , the through bore  16 , into which abutment screw  30  is inserted in use, is visible. In this embodiment, the deformable element is provided by an annular ring  17  surrounding the through bore  16 .  FIG. 12  shows a cross section view of abutment  10  with annular ring  17  surrounding through bore  16 . Again, as abutment screw  30  is inserted into through bore  16  and tightened, the base  35  (in this case providing the corresponding contact surface) of head  31  will be compressed over deformable element, in this case, annular ring  17 , so as to deform it to provide a seal between abutment screw  30  and abutment  10 . This again provides a barrier to bacteria entry into the micro leakage path and reduces risk of infection. In this case, the base  35  of head  31  may be planar rather than angled as in a previous example. 
       FIG. 13  shows a close up view of the seal so formed, showing the deformation of deformable element, in this case, annular ring  17 .  FIG. 30   a  shows an alternate embodiment where the deformable element is located on the abutment screw  30  and element  17  presses into the screw  30 , thereby forming a seal. 
     In one example, the height of annular ring  17  is about 0 05 mm and the width of annular ring  17  is about 0.05 mm (prior to deformation). Of course, any other suitable dimensions may be used, including but not limited to about 0.01 mm to about 0.1 mm, about 0.04 mm, about 0.06 mm, about 0.03 mm and about 0.07 mm or any combination thereof. 
     The above embodiments have provided examples of forming the seal between the abutment screw  30  and the abutment  10 . In other embodiments and aspects, the seal may alternatively, or also, be formed between the fixture  20  and the abutment  10 , as will now be detailed. 
     In one embodiment of this aspect, as shown by way of example in  FIG. 14 , fixture  20  is provided with an annular corner  26  on lip  25  of the abutment receiving well, which defines the fixture interior  24 . The abutment base  12  of abutment  10  is received in fixture interior  24  to be retained by tightening the abutment screw  30  as previously described.  FIGS. 15 ,  16  and  17  show various examples of abutment  10  configurations that may be used in this aspect. 
     In some exemplary embodiments of this aspect of the present invention, the fixture interior  24  of the fixture  20  has a bottom geometrical configuration, for instance a lobe shaped geometrical configuration  27 , and the protruding bottom part of the abutment  10  has a corresponding geometrical configuration  18  as illustrated in  FIGS. 15 ,  16  and  17 , to prevent otherwise resist against rotation between these two parts when coupled together. 
     The abutment  10  may have a substantially curved, conical outer surface with the upper edge having the wider diameter and the bottom, fixture-connecting part having a smaller diameter, as illustrated. A feature in these particular embodiments for the three different examples of abutments  10  illustrated in  FIGS. 15 ,  16  and  17  may be that the bottom tapered outer surface  12  which cooperates with the annular corner  26  of the fixture  20  when the two parts are coupled together as shown in  FIG. 18 . This provides a concave outer contour of the connection between the abutment and the fixture. 
     In this example, the deformable element is provided by the annular corner  26 . When the abutment  10  is placed in the fixture  20  and the abutment screw  30  is tightened as previously described, the abutment base  12 , (in this case acting as the corresponding contact surface) is pressed down onto annular corner  26 , which deforms to provide a seal between abutment  10  and fixture  20 .  FIG. 19  shows a close up view of the seal formed therebetween. 
     The deformable element may also deform upon application of other force, such as by downward pressure on abutment  10 , rather than, or in conjunction with, tightening of the abutment screw  30 . 
     In some embodiments, the outer surface of the abutment  10  and/or the fixture  20  might be modified in order to improve the skin tissue integration. Different types of structured or coated surfaces might be used, for instance hydroxyapatite (HA) coated surfaces. In this case it should be understood that the coating might be applied on the fixture and the abutment separately, or applied on a pre mounted implant device. 
     In a further embodiment of this aspect, the deformable element may be provided on the abutment  10  as shown in  FIG. 30   b , which corresponds to the view of  FIG. 19 , and, in some embodiments, the deformable element may be in the form of an annular ring, as depicted in  FIGS. 20 and 21 . In the embodiment of  FIG. 20 , the deformable element is provided by abutment annular corner  19  on the abutment base  12 . In this embodiment, the lip  25  of fixture  20  may be a more conventional rounded shape, which provides the corresponding contact surface for the deformable element, in this case, abutment annular corner  19 . As in the previous example, abutment  10  is placed in the fixture  20  and when abutment screw  30  is tightened, abutment  10  is pressed down onto fixture  20 . In this arrangement, deformable element (abutment annular corner  19 ) will be deformed against the lip  25  to form a seal between the abutment  10  and the fixture  20 . 
       FIG. 22  is a close up view of the seal formed between the abutment  10  and the fixture  20  of  FIG. 21 . 
       FIG. 23  shows an example of another embodiment of a medical implant system  100 , comprising abutment  10 , fixture  20  and abutment screw  30 . In this example, the system is designed so as to provide a seal between the abutment  10  and the abutment screw  30 . In this case, this seal is provided by an arrangement similar and/or the same as that described earlier with reference to  FIGS. 5A ,  5 B,  5 C,  6  and  7 . With respect to the embodiment of  FIG. 23 , the deformable element is provided on the abutment screw  30  in the form of an angled flange that upon tightening of abutment screw  30  (or application of other force), deforms against the corresponding contact surface (in this case abutment interior base  14 ) to form the seal.  FIG. 31  depicts an alternate embodiment where engagement between the abutment screw  30  and the abutment  10  is depicted, and the abutment interior base  14  of abutment  10  deforms. Specifically, flange  36  is pressed into the surface of the abutment interior base  14 , to provide a seal. As will be understood from  FIG. 31 , in this alternate embodiment, the corresponding contact surface, in this case the abutment interior base  14 , may itself deform slightly to further increase the seal formed therebetween. The degree of resulting deformation of the abutment screw and/or the abutment may vary between embodiments. In some embodiments, all or substantially all of the overall deformation may occur in the abutment screw  30 , while in some embodiments, all or substantially all of the deformation may occur in the abutment  10 , while in some embodiments, the amount of deformation may be more evenly distributed between these two components. 
       FIG. 24  shows another embodiment of a medical implant system  100  comprising abutment  10 , fixture  20  and abutment screw  30 . In this example, the system is designed to provide a seal between abutment  10  and fixture  20 . In this case, the seal is provided by the same arrangement as described earlier with reference to  FIGS. 14 to 19 . That is, that the deformable element is provided on the fixture  20  in the form of an annular corner  26  provided on the lip  25  of fixture  20 , that upon tightening of abutment screw  30  9or application of other force), deforms against the corresponding contact surface (in this case abutment base  12 ) to form the seal.  FIG. 32  depicts an alternate embodiment where engagement between the bone fixture  20  and the abutment  10  is depicted. The depicted deformation of the abutment  10  is a result of the annular corner  26  of lip  25  of the fixture  20  being pressed into the surface of the abutment  10 , to provide a seal. As will be understood from  FIG. 32 , in this alternate embodiment, the corresponding contact surface, in this case the annular corner  26 , may itself deform slightly to further increase the seal formed therebetween. The degree of resulting deformation of the fixture  20  and/or the abutment  10  may vary between embodiments. In some embodiments, all or substantially all of the overall deformation may occur in the abutment  10 , while in some embodiments, all or substantially all of the deformation may occur in the bone fixture  20 , while in some embodiments, the amount of deformation may be more evenly distributed between these two components. 
       FIG. 25  shows yet another embodiment of a medical implant system  100  comprising abutment  10 , fixture  20  and abutment screw  30 . In this example, the system is designed to provide a seal between the abutment  10  and the abutment screw  30  as well as between the abutment  10  and fixture  20 . In this case, the first seal is provided by the same arrangement as described above with reference to  FIG. 23 . That is, that the deformable element is provided on the abutment screw  30  in the form of an angled flange that upon tightening of abutment screw  30  (or application of other force), deforms against the corresponding contact surface (in this case abutment interior base  14 ) to form the seal. The second seal is provided by the arrangement described above with reference to  FIG. 24 . That is, that the deformable element is provided on the fixture  20  in the form of an annular corner  26  provided on the lip  25  of fixture  20 , that upon tightening of abutment screw  30  9or application of other force), deforms against the corresponding contact surface (in this case abutment base  12 ) to form the seal. Accordingly, the arrangement of  FIG. 25  is a combination of both the arrangements of  FIGS. 23 and 24 . 
     In yet further embodiments, any combination of any two or more of the seals previously described may be used, including two different seals provided between the abutment  10  and the abutment screw  30  as shown in  FIGS. 5 to 10  as well as  FIGS. 11 to 13 . By way of example,  FIG. 33  depicts yet another embodiment of a medical implant system  100  comprising abutment  10 , fixture  20  and abutment screw  30 . In this example, the system is designed to provide a seal between the abutment  10  and the abutment screw  30  as well as between the abutment  10  and fixture  20 . In this case, the first seal is provided by the alternate arrangement as described above with reference to  FIG. 23  and  FIG. 31 . That is, that the deformable element is provided on the abutment  10  (in this case (in this case, abutment interior base  14 ) such that that upon tightening of abutment screw  30  (or application of other force), the abutment  10  deforms against the corresponding contact surface of the abutment screw  30  to form the seal. The second seal is provided by the arrangement described above with reference to the alternate arrangement described above with reference to  FIG. 24  and  FIG. 32 . That is, that the deformable element is again provided on the abutment  10  (in this case, abutment base  12 ) such that upon tightening of abutment screw  30  (or application of other force), the abutment  10  deforms against the corresponding contact surface (annular corner  26  provided on the lip  25  of fixture  20 ) to form the seal. Accordingly, the arrangement of  FIG. 25  is a combination of both the alternate arrangements of  FIGS. 23 and 24  described above. 
     It will be appreciated that the various deformable elements described may be provided by any suitable means, including by turning, during or after the usual component production process. 
     The provision of the deformable element(s) in the various components of the medical implant system  100  provide for a unique method of implanting the medical implant system. 
     The steps of one possible method of implanting the medical implant system  100  are shown in  FIG. 26   a . At step  200 , the abutment  10  is located in the abutment receiving well of fixture interior  24  of the already implanted fixture. At step  201 , the abutment screw  30  is inserted in the through bore  16  of the abutment  10  and into the fixture  20 . In step  202 , force is applied to the implant system until the deformable element(s) deforms to provide the seal(s) between the various components of the medical implant system, thereby reducing the risk of infection in the user or patient. In one example, the force may be applied by way of pressure on the abutment. 
     In another example, as shown in  FIG. 26   b , the same steps  200  and  201  may be used, however, in step  202 ′, the force may be applied by way of tightening the abutment screw  30 . In one example, the abutment screw is tightened using a torque of greater than about 15 Ncm, and including about 15 Ncm to about 20 Ncm, and about 20 Ncm to about 30 Ncm. In one particular example, the torque used is about 25 Ncm. 
     In some embodiments, the, or part of, the surfaces of one or more of the components, such as the abutment screw  30  may be coated with a friction-reducing material such as diamond like carbon (DLC). In these embodiments, the required torque or other force will be reduced. 
       FIGS. 27   a ,  27   b  and  27   c  illustrate these steps  200 ,  201  and  202 ′. In  FIG. 27   a , the abutment  10  is located inside fixture  20 . In this example, fixture  20  has already been implanted and anchored in the bone  50  of the patient&#39;s skull, in a previous procedure and allowed to heal. This example method therefore begins with the location of the abutment  10  in fixture  20 . This is done through an opening created in the tissue  5  of the patient. 
     In  FIG. 27   b , the abutment screw  30  is inserted into the abutment  10  and the fixture  20  and in  FIG. 27   c , the abutment screw  30  is tightened using an insertion tool  40 . This tightening causes any deformable elements in the system to deform and form seals to reduce the risk of bacteria entering into the micro leakage path and thus reducing risk of infection. 
     The seals may be provided as previously described, between the abutment screw  30  and the abutment  10 , the abutment  10  and the fixture  20 , or both, with the locations of these discernible from the dotted lines superimposed on  FIG. 27   c.    
     Embodiments utilizing multiple deformable elements may use different types of deformable elements/deformable elements of different geometries as detailed herein and/or variations thereof. 
     In view of the above, it can be seen that in at least one aspect of the invention, there is a medical implant system for attaching a hearing device to a user is provided. In one form, the medical implant system comprises a fixture, an abutment and an abutment screw for connecting the abutment to the fixture. In this aspect, there is provided on one or more of these components, a deformable element that deforms to form a seal between the one or more components of the medical implant system. 
     In view of the above, it can be seen that in at least one other aspect of the invention, there is an abutment for use in a medical implant system comprising a fixture, the abutment and an abutment screw. In one form, the abutment comprises a through bore for receiving the abutment screw and a deformable element that is deformed against the abutment screw when the abutment screw is inserted in the through bore and tightened. 
     In view of the above, it can be seen that in at least one other aspect of the invention, there is an abutment screw that comprises a head, an elongate main body and a deformable element that may be deformed between the abutment screw and an abutment to provide a seal upon inserting the abutment screw through the through bore of the abutment and tightening the abutment screw. 
     In view of the above, it can be seen that in at least one other aspect of the invention, there is a fixture for use in a medical implant system. The fixture comprises a main body, an abutment receiving well and a screw thread for anchoring the fixture into bone. In one form, a deformable element is provided as an annular corner of the abutment receiving well. 
     In view of the above, it can be seen that in at least one other aspect of the invention, there is a method of implanting a medical implant system into a user. The medical implant system comprises a fixture, an abutment and an abutment screw. The method involves locating the abutment in an abutment receiving well of the fixture, inserting the abutment screw in a through bore of the abutment and into the fixture, and applying a force to the implant. In one form, this force is provided by tightening the abutment screw until a deformable element deforms to provide a seal between one or more of the components of the implant system. 
     In some embodiments, the seals formed by the embodiments detailed herein and/or variations thereof may form a hermetic seal. In some embodiments, the seal is an air tight seal. 
     Throughout the specification and the claims that follow, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprising” and “including” will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers. 
     It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention. 
     While various embodiments of the present technology have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the technology. For instance, features described as part of one implementation can be used on another implementation to yield a still further implementation. Thus, the breadth and scope of the present technology should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. All patents and publications discussed herein are hereby incorporated in their entirety by reference thereto.