Patent Publication Number: US-2022226081-A1

Title: An orthodontic abutment

Description:
TECHNICAL FIELD 
     The invention relates to an orthodontic abutment for fixing to dental implants. 
     BACKGROUND 
     A dental implant is an element formed as a screw or a cylinder having a thread, which is surgically fixed to a jawbone. Dental implants are typically used as a base for mounting thereon artificial teeth, via abutments. 
     There are known abutments, which not only constitute a base for mounting an artificial tooth, but also have retention elements for attaching orthodontic elements. 
     For example, a European patent application EP1961397A1 discloses an orthodontic assembly containing a retention element in the form of a button with an eyelet. 
     A European patent application EP2083741A2 discloses an orthodontic implant hub with a retention element in the form of a slot adapted to connect a dome to an orthodontic wire. 
     The disadvantage of the currently known orthodontic abutments mounted on dental implants is that they offer limited scope of cooperation with other orthodontic elements, as they typically have only a single retention element. Therefore, there is a need to provide an improved orthodontic abutment that would be tailored to the individual needs of the patient and would allow for broader possibilities of cooperation with other orthodontic elements. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention relates to an orthodontic abutment comprising a base suitable for fixing the orthodontic abutment to an implant; a cap fixed to the base; a plurality of retention elements arranged along a side wall of the cap, suitable for receiving orthodontic elements. The retention elements include: a bracket with wings; a hook arranged under one of the wings of the bracket; a projection arranged on the cap oppositely with respect to the bracket; a hollow tube formed inside the projection; a curved rod hook arranged on the projection below the tube; and a button with an eyelet arranged on the projection above the tube. 
     The cap may comprise a straight hook in the form of a straight plate terminated by a rounded thickening. 
     The cap may comprise a curved hook in the form of a bent plate terminated by a rounded thickening. 
     The bracket may comprise a movable gate arranged between the wings of the bracket such that in a closed position the movable gate partially closes a slot. 
     The button with the eyelet may be arranged on the projection. 
     The button with the eyelet may be arranged on top of the cap. 
     The cap may be integrated with the retention elements as a uniform element made in the 3D printing process. 
     The cap together with the retention elements may be made of a cobalt-chromium-tungsten alloy. 
    
    
     
       BRIEF DESCRIPTION OF FIGURES 
       Various embodiments are herein described, by way of example only, with reference to the accompanying drawings, wherein: 
         FIGS. 1 and 2  show a first embodiment of the orthodontic abutment; 
         FIG. 3  shows a second embodiment of the orthodontic abutment. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. 
     An orthodontic abutment comprises a base  1  for fixing the abutment to an implant and a cap  2  fixed to the base  1 . The cap  2  can be fixed to the base  1  by adhesive or other suitable means. The base  1  can be fixed to the implant with a threaded connection or other suitable means. The cap  2  has a form of a small dome and comprises at least three retention elements. 
       FIGS. 1 and 2  show a first embodiment of the orthodontic abutment. The retention elements include a bracket  20  with a straight hook  21 , a hollow tube  31  with a curved rod hook  32  and a button  40  with an eyelet  41 . 
     This type of orthodontic abutment is particularly suitable for orthodontic treatment. The retention elements  20 ,  21 ,  31 ,  32 ,  40 ,  41  are adapted to be coupled with orthodontic elements such as wires, elastics, springs, ligatures or rubber bands, for correcting dental changes. Use of a variety of retention elements allows correcting dental changes by movement of teeth in three dimensions, for a plurality treatment purposes concurrently. Furthermore, various treatment options can be applied consecutively, without the need to replace the cap  2 . 
     For example, the slot  20 A of the bracket  20  can be used to mount an orthodontic arch in the form of a wire, usually made of nickel and titanium alloy, to eliminate dental gaps and to open or close the bite. Moreover, an orthodontic arch can be mounted in the slot of the orthodontic abutment, in the form of titanium wire (TMA) or a bent steel wire for tooth displacement and closure of tooth spaces. 
     The straight hook  21 , which is integrated with the bracket  20  and is located under one of the wings of the bracket  20  can be used for attaching elastics, such as Class I elastic rubber bands or intermaxillary rubber bands, or elastic power chains, which are also used to treat malocclusions and contribute to bite correction, improving the fit between the upper and the lower teeth and/or jaws (bite). A steel orthodontic ligature can also be attached to the straight hook  21  to support the arch in the slot  20 A of the bracket  20 , or closed springs, which are used to close dental spaces. Preferably, the straight hook  21  has a form of a straight plate  21 A terminated with a rounded thickening  21 B, which allows stable and secure fixing of the orthodontic elements. 
     The hollow tube  31  can be used to fix orthodontic wire, orthodontic arch (most often nickel and titanium alloy elastic arches), while the curved rod hook  32  located below the hollow tube  31  can be used to fix elastics, such as Class I elastic rubber bands or intermaxillary rubber bands, or elastic power chains. The hollow tube  31  is a through opening formed across the projection  30 , having an essentially horizontal axis. 
     The projection  30  and the bracket  20  are arranged on the cap  2  opposite each other, i.e. on the opposite sides of the circumference of the cap  2 . 
     The button  40  with the eyelet  41  can be used to thread metal ligature or elastic thread through the eyelet  41 , while elastics and springs can be attached to the button  40 . Preferably, the button  40  with the eyelet  41  is located above the hollow tube  31 . However, depending on the patient&#39;s individual needs, it can be placed for example on the top of the cap  2 . Preferably, the eyelet  41  is an opening with an axis that extends in a substantially horizontal plane. 
       FIG. 3  shows a second embodiment of the orthodontic abutment. In the second embodiment, the cap  12  comprises a bracket  120  with a curved hook  121 , wherein the bracket  120  has a movable gate  120 B, which is arranged between its wings, such that in a closed position it partially closes a slot  120 A. This type of the bracket is called a self-ligation bracket. When the orthodontic arch is placed into the slot  120 A, the movable gate  120 B, in the closed position, holds the wire in place and prevents the orthodontic arch to escape from the slot  120 A. In an open position of the movable gate  120 B, the slot  120 A is opened and allows the orthodontic arch to be introduced into the slot  120 A or to be withdrawn from the slot  120 A. 
     The curved hook  121 , similarly as the hook  21  of the first embodiment, is integrated with the bracket  120  and is located under one of the wings of the bracket  120 . The curved hook  120  can be used for attaching elastics, such as Class I elastic rubber bands or intermaxillary rubber bands, or elastic power chains, which are also used to treat malocclusions and contribute to bite correction, improving the fit between the upper and lower teeth and/or jaws (bite). The curved hook  121  may have a form of a bent plate  121 A terminated by a rounded thickening  121 B, which allows a stable and secure fixing of the orthodontic elements. 
     The customised cap  2 ,  12  can be manufactured by a 3D printing process using a suitable 3D printer, which allows producing a design tailored to the individual patient. The cap  2 ,  12  together with retention elements  20 ,  120 ,  21 ,  121 ,  31 ,  32 ,  40 ,  41  is preferably made of a biocompatible material, for example from a dental alloy in a form of powder used in laser melting technology, which contains cobalt, chromium and tungsten. One particularly suitable alloy contains 61% cobalt, 27.5% chromium, 8.5% tungsten, 1.6% silicon and less than 1% carbon, iron and manganese and optionally other additives up to 100%. 
     The orthodontic abutment according to the invention is capable of correcting dental changes without the need to mount complete orthodontic braces. By means of the retention elements, the orthodontic abutment allows for applying forces necessary to effect a desired dental movement, while eliminating the need to take into account the counter-reaction forces. In particular, the hollow tube  31  and the slot of the bracket  20 ,  120  can be used simultaneously as elements for fixing the compact arm of force, which allows the force to be applied from the centre of resistance of the tooth, allowing for precise mesial or distal displacement of the tooth, which results in the most efficient tooth displacement. 
     While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. Therefore, the claimed invention as recited in the claims that follow is not limited to the embodiments described herein