Abstract:
A dental superstructure attaching system for use with a dental implant is provided. The system comprises a longitudinal member being connectable with an implant or an implant connecting member via an at least partially curved interface area. The longitudinal member comprises a main member forming the lingual part of said longitudinal member, and a lever member forming the buccal or labial part of said longitudinal member. The longitudinal member further comprises means for urging said lever member and said main member away from each other, such that said longitudinal member is secured to said implant or implant connecting member. A dental superstructure connection device in such a system, and methods for attaching a dental superstructure to a dental implant via such a system, are also provided.

Description:
TECHNICAL FIELD  
       [0001]    The present invention pertains to a dental superstructure attaching system for use with a dental implant. More specifically the present invention pertains to a system to be arranged in between a dental implant and a dental superstructure/framework, members thereof, and methods for attaching a dental superstructure to a dental implant via such a system. 
       BACKGROUND  
       [0002]    The goal of a dental implant system is to restore the patient to normal function, comfort, aesthetic, speech and health regardless of the current oral condition. These implant systems are based on the implantation of dental implants, such as dental implants made of biocompatible titanium, through insertion into the patient&#39;s jawbone. In this respect, the use of biocompatible titanium started in Sweden as early as 1950, and has since then been further developed and spread world-wide. During the 1980&#39;s a number of implant systems entered the world market. 
         [0003]    When securing a dental prosthesis to the jaw of a patient, it is commonly known to attach a superstructure to osseointegrated dental implants. However, since the position and angle of the dental implants vary greatly from patient to patient, the use of angled distances is common. These distances are placed upon the dental implant, and the superstructure is then most often cemented to the distances, since it is difficult to retain the superstructure to such distances by means of screws. However, when using separate distances, these will inevitably extend—at least to some extent—in the axial direction of the dental implant. It is then often very difficult or even impossible to apply the superstructure on such distances, since the application of the superstructure calls for a substantially parallel arrangement of the distances. Also, the mounting process when using such distances is very complicated and cumbersome, since a vast number of different distances must be tested on the implants, to find the needed match. Also, interfaces between the distances and the superstructure are hygienically bad. 
         [0004]    W 0 01/70127 describes an arrangement comprising a spacer element for an implant. The spacer implant has a screw bore at a fixed angle relative the longitudinal axis of the implant, such that a holder configured to support a superstructure may be mounted in said screw bore at the corresponding angle. Hence, using this kind of system the mouth of the connection channel between the superstructure and the spacer element may be arranged with a freedom of choice in accordance with the angle of the screw bore of the spacer element. 
         [0005]    However, the freedom of the above described system is limited to the pre-determined angle of the spacer element, and the system requires specially adapted tools for assembling the arrangement. 
         [0006]    Thus, there is a need for a new device and method allowing for improved construction of angled distances. 
       SUMMARY OF THE INVENTION 
       [0007]    Accordingly, the present invention preferably seeks to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and disadvantages singly or in any combination and solves at least the above mentioned problems by providing a method and a device according to the appended patent claims. 
         [0008]    An object of the present invention is to provide a system for allowing a superstructure to be connected to said system without any visible attachment means. 
         [0009]    A further object of the present invention is to provide a single system which may be connected to a dental implant at various angles. 
         [0010]    A yet further object of the present invention is to provide a system allowing the superstructure to be connected to said system by means of a standard screw. 
         [0011]    The general solution according to the invention is a two part superstructure attachment system forming a distance to be connected to a superstructure, which distance is angularly displaceable relative an implant and securable to said implant by a clamping effect caused by relative movement between the two parts. 
         [0012]    In an aspect of the invention there is thus provided a dental superstructure attaching system for use with a dental implant, comprising a longitudinal member being connectable with an implant or an implant connecting member via an at least partially curved interface area, said longitudinal member comprising a main member forming the lingual part of said longitudinal member, and a lever member forming the buccal or labial part of said longitudinal member, wherein said longitudinal member further comprises means for urging said lever member and said main member away from each other, such that said longitudinal member is secured to said implant or implant connecting member. 
         [0013]    In another aspect of the invention there is provided a dental superstructure connection device for connection to a dental implant with a spherical implant head or an implant connecting member with a spherical distal portion, comprising a longitudinal member with a spherically shaped recess in its proximal end for connection with said implant or implant connecting member, a main member and a lever member, said main member comprising a part of said spherically shaped recess and said lever member comprising another part of said spherically shaped recess, and means for urging said lever member and said main member away from each other distally of said spherically shaped recess, such that said parts of the spherically shaped recess are forced towards each other. 
         [0014]    In another aspect of the invention there is provided a method for attaching a dental superstructure to a dental implant, comprising the steps of: mounting an implant connecting member to said implant, said implant connecting member having an at least partially curved area at its distal end, providing a longitudinal member having a proximal end engageable with the shape of the distal end of said implant connecting member, said longitudinal member comprising a main member forming the lingual part of said longitudinal member, and a lever member forming the buccal or labial part of said longitudinal member, arranging a dental superstructure onto said longitudinal member, and securing said dental superstructure to said longitudinal member by urging said lever member and said main member away from each other. 
         [0015]    In another aspect of the invention there is provided a method for attaching a dental superstructure to a dental implant having at least partially curved area at its distal end, comprising the steps of: providing a longitudinal member having a proximal end engageable with the shape of the distal end of said implant connecting member, said longitudinal member comprising a main member forming the lingual part of said longitudinal member, and a lever member forming the buccal or labial part of said longitudinal member, and arranging a dental superstructure onto said longitudinal member, and securing said dental superstructure to said longitudinal member by urging said lever member and said main member away from each other. 
         [0016]    Further advantageous features of the invention are defined in the dependent claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    These and other aspects, features and advantages of which the invention is capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which 
           [0018]      FIG. 1  is a schematic cross-section of a system according to an embodiment; and 
           [0019]      FIG. 2  is a schematic cross-section of a longitudinal member of the system shown in  FIG. 1 . 
       
    
    
     DESCRIPTION OF EMBODIMENTS  
       [0020]    Several embodiments of the present invention will be described in more detail below with reference to the accompanying drawings in order for those skilled in the art to be able to carry out the invention. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The embodiments do not limit the invention, but the invention is only limited by the appended patent claims. Furthermore, the terminology used in the detailed description of the particular embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. 
         [0021]    In general, the present invention pertains to a system and devices thereof, for obtaining a dental superstructure, and subsequently a dental prosthesis, comprising said dental superstructure and an appropriate facing material thereon, without any form of screw channel mouth in the masticating surface. The system instead assures that the superstructure may be attached to a dental implant through a tightening screw lingually. In this way a more aesthetic and endurable construction may be obtained. 
         [0022]    According to the embodiment disclosed in  FIG. 1  and  FIG. 2 , a superstructure attachment system  100  is disclosed, said system comprising a dental implant connecting member  101  and a longitudinal member  102  acting as a superstructure connecting part. The longitudinal member  102  comprises two portions, a main member  102   a  and a lever member  102   b,  which in use are held together by a screw member arranged in a correspondingly threaded screw hole  103 . The two members  102   a,    102   b  have a substantially longitudinal extension, and are intended to extend distally from the implant connecting part  101 , and therefore also distally from the jaw bone to which an implant (not shown) is secured. The screw hole  103  extends substantially transversally in respect of the longitudinal extension of the two members  102   a,    102   b,  and runs at least through portion  102   a.    
         [0023]    The thread of the screw hole  103  may be such that at least a part of the screw hole  103   a  in portion  102   a  is threaded. Portion  102   b  may comprise a receiving seat  103   b,  for receiving the screw member arranged in the screw hole  103   a  and protruding from an interface surface  105   a  on the portion  102   a.  In this way, the portion  102   a  may be pushed away from the portion  102   b  by screwing the screw member into the screw hole  103  and pushing onto the receiving seat  104 . The portion  102   b  may also have a threaded part in the receiving seat  104 . In this way the screw member may be prearranged in the screw hole, holding portion  102   a  and  102   b  together during application of the superstructure thereon. The thread of the screw hole part in portion  102   b  may be threaded in the opposite direction to the thread in the screw hole  103   a  of portion  102   a.  In this way the separation action between portion  102   a  and  102   b  may be amplified, such that portion  102   a  and  102   b  are separated by two thread heights during every rotation of the screw member arranged in the screw hole  103 . 
         [0024]    The implant connecting member  101  and the longitudinal member  102  are connected to each other at a curved interface area  106  forming a ball-socket joint. The ball-socket joint is formed by a partially spherically shaped protrusion  110  arranged at the distal end of the dental implant member  101 , and a recess  104   a,    104   b  having a corresponding inverted shape and configured to engage with said protrusion  110 . 
         [0025]    The functionality of the superstructure attachment system  100  will now be described. The dental implant connecting member  101  is tightly attached to the dental implant by a screw  109  threadably engageable with the dental implant. The main member  102   a  and the lever member  102   b  of the longitudinal member  102  are fitted to engage with partially spherically shaped distal end of the implant connecting member  101 . As the lever member  102   b  and the main member  102   a  are in close contact along their longitudinal axis, the longitudinal member  102  may be angularly displaced relative the longitudinal axis of the implant connecting member  101  by means of the ball-socket joint formed at the interface between the implant connecting member  101  and the longitudinal member  102 . 
         [0026]    Then, a superstructure (not shown), with cavities adapted for receiving the longitudinal member  102 , is arranged onto the longitudinal member(s). The cavities of the superstructure are shaped such that the mouth for receiving the longitudinal member comprises a seat for a flange  107  in a proximal zone of the longitudinal member  102 . The cooperation between the flange  107  and the corresponding seat in the superstructure will enhance the leverage of the separation force from separation of the main member  102   a  and the lever member  102   b,  since a distinct leverage point will be formed at the interface between the two. 
         [0027]    When the superstructure has been slid onto the longitudinal portion and the longitudinal member  102  consequently is positioned at a desired angle, the screw inserted into the screw bore  103  of the main member  102   a  is tightened such that it protrudes outside the main member  102   a  and consequently causing a relative movement between the lever member  102   b  and the main member  102   a.  As a distance between the lever member  102   b  and the main member  102   a  is induced, the partially spherically shaped recess  104   a,    104   b  of the longitudinal member  102  will consequently clamp longitudinal member  102  to the implant connecting member  101 , such that the longitudinal member  102  is tightly connected to the implant connecting member. 
         [0028]    A superstructure may be attached to the system  100  after the position of the longitudinal member  102  relative the implant connecting member  101  has been secured. Preferably, the superstructure comprises at least one interior channel for receiving a longitudinal member  102 . More preferably, each one of the interior channels is reachable from the oral cavity by an opening, such that the superstructure may be further attached to the system  100  by means of a screw. Hence, the opening is aligned with the screw hole  103  of the main member  102   a  of the longitudinal member  102 . 
         [0029]    The dental implant connecting member  101  is preferably a two-part piece, comprising a bolt and a fitting. The bolt has a threaded part  109  and tool receiving part  108  such that it may be tightly screwed into the implant. Before the bolt is fitted into the implant, it is inserted into the fitting such that the fitting will be secured relative the implant upon tightening of the bolt. For this purpose, the fitting is equipped with a protrusion  112  and a recess  111  which engage with the implant and/or the bone of the patient for preventing rotational movement of the fitting relative the implant. 
         [0030]    The tool receiving part  108  is formed as a cylindrical or conical recess in the spherically shaped distal end, wherein the longitudinal axis of said recess is aligned with the longitudinal axis of the implant. Hence, the distal end is formed as a sphere integrally formed with the protrusion/recess part  111 ,  112 , with a bore extending from the upper end through the sphere. 
         [0031]    With reference to  FIG. 2 , the longitudinal member  102  will be described in more detail. Here, the longitudinal member  102  is formed by the main member  102   a  and the lever member  102   b.  When the lever member  102   b  is in close contact with the main member  102   a,  the longitudinal member is generally extending in a longitudinal direction and consists of three general parts; a cylindrical part, a flange, and a conical part. The cylindrical part is arranged at the distal end of the longitudinal member  102  and extends distally from the flange  107 . Proximally of said flange  107 , a conical part is arranged. The conical part comprises a proximal recess having a curvature corresponding to the distal end of the implant connecting member  101 . 
         [0032]    The main member  102   a  and the lever member  102   b  are facing each other via the surfaces  105   a,    105   b,  which form a longitudinal interface between the lever member  102   b  and the main member  102   a.  The distal portion of the interface between the surfaces  105   a,    105   b  is preferably substantially aligned with the longitudinal axis of the longitudinal member  102 , while the proximal portion of the interface between the surfaces  105   a,    105   b  is preferably angled relative the longitudinal axis of the longitudinal member  102 , such that the interface surface  105   a  has a normal facing proximally and transversally and the interface surface  105   b  faces distally and transversally, with respect to the longitudinal direction of the member  102 . In this way, the demounting of the superstructure from the implant connecting member  101  and thus the implant may be facilitated, since the superstructure may be lifted in the distal direction once the screw member in screw hole  103  stops to exert pressure on the lever member  102   b.  In this position the superstructure may be lifted together with the main member  102   a,  due to the angled arrangement of the interface surfaces  105   a,    105   b  in relation to the central axis of the longitudinal member  102 . Hence, this arrangement of an at least partially angled interface area facilitates separation of the main member  102   a  and the lever member  102   b  by means of reducing the risk of that the members are stuck to each other. In other embodiments the angled interface portion is made longer; e.g., the entire interface area may be angled relative the longitudinal axis of the longitudinal member  102 . The interface area formed by the surfaces  105   a,    105   b,  when viewed from above, may also be planar or curved. 
         [0033]    Preferably, the interface between the surfaces  105   a,    105   b  is ending at a position being located at the center of the spherical recess  104   a,    104   b  of the proximal end of the longitudinal member  102 . In other embodiments, however, the interface end point could be located slightly off-center. 
         [0034]    As shown in  FIG. 2 , the through hole  103   a  of the main member  102   a  is substantially perpendicular to the longitudinal axis of the main member  102   a.  The lever member  102   b  has a corresponding seat  103   b  for receiving a screw protruding through said main member  102   a.    
         [0035]    In other embodiments, the screw hole  103   a,    103   b  may be arranged differently and the engaging screw members may then be correspondingly adapted. For example, the screw hole  103   a,    103   b  may extend through both the portions  102   a,    102   b,  but the screw hole part corresponding to portion  102   a  having opposite threading direction than the threading direction in the screw hole part corresponding to portion  102   b . Analogously, the screw member may have the corresponding threads, such that screwing action on the screw member in the screw hole  103  will result in increased separation effect. One rotation of the screw member will then result in a separation of the portions  102   a,    102   b  corresponding to two thread heights. 
         [0036]    In further embodiments, the threaded holes  103   a,    103   b  may be arranged at a different angle such that the mouth of the through hole  103   a  is directed slightly distally. 
         [0037]    The diameter of the longitudinal member  102  is preferably in the range of 2 to 5 mm, such that it may be accommodated within the oral cavity while still providing sufficient strength and stability to the superstructure. The total length of the longitudinal member is in the range of 10 to 15 mm, and hence the displacement of the lever member  102   b  relative the main member  102   a  is sub-millimeter at the most distal end in order to provide sufficient clamping of the longitudinal member  102  to the implant connecting member  101 . 
         [0038]    Although the present invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims and, other embodiments than the specific above are equally possible within the scope of these appended claims. 
         [0039]    In the claims, the term “comprises/comprising” does not exclude the presence of other elements or steps. Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by e.g. a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms “a”, “an”, “first”, “second” etc do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.