Patent Publication Number: US-2020281696-A1

Title: Dental tool, prosthetic component, and tool and component assembly

Description:
The present invention relates to a tool for capturing, transporting and fixing dental prosthetic components and screws. Specifically, the present invention relates to a wrench for capturing and fixing screws (prosthetic components) in dental implants. 
     RELATED ART 
     After installing an implant in a patient&#39;s mouth, the dentist must install/fix a component, onto which the dental prosthesis will be installed. 
     However, as each patient has a different anatomy, the dentist must test various types of prosthetic components until finding the most suitable for the treatment case. 
     Thus, when carrying out tests, the dentist must use a capture tool (wrench) to transport the prosthetic component from the component case to the patient&#39;s mouth. It is essential that this transport occurs safely, mainly because these components are extremely small and easily lost should they fall. Furthermore, for hygienic reasons, if the component is found, it can no longer be used for testing, as it must be sterilized again. 
     Thus, there is a need for a wrench that can safely capture and transport the component. 
     To achieve this object, the tools available in the state of the art such as, e.g., the ones illustrated in  FIGS. 1 and 2  include a cone shape end, which allows for temporary fastening of the component for transport to the installation site. 
     After this testing process and finding the suitable component for fastening the implant located in the patient&#39;s mouth, the dentist needs to fix the screw. For such, a ratcheting torque wrench is used, which is different from the transport wrench, performing the torque necessary to hold the component in the implant. 
     It is often necessary to switch tools, as the cone in the torque wrench is used only to temporarily fasten the component to the wrench, preventing the tip of the wrench from fully penetrating the component, i.e. the tip of the wrench is not in contact with the entire internal surface of the component (see  FIGS. 1 and 2 ). 
     Thus, when the dentist performs torque, the component will be deformed (dilation of the screw head). 
     Thus, in order to avoid this defect, the wrench used to fasten the component in the implant must have a straight end (tip), i.e., without the cone, allowing the whole tip of the wrench to fully penetrate the internal length of the screw. As a result, when torque is performed, said deformation will not occur. 
     However, the need to switch tools is cumbersome to dentists. Consequently, many professionals choose to use their own capture wrench to provide torque, deforming the screw. 
     Furthermore, torque wrenches are typically hexagonally shaped. Due to this shape, the wrench contact area with the component is reduced. If by mistake the dentist delivers more torque than necessary for fixing the screw, deformation of the ridges of the wrench and dilation of the screw head are likely to occur. 
     This constant deformation, dilating the head of the component and the ridges of the tool, causes the wrench to not fit properly to the component head at certain moments, making rotation impossible in order to tighten the prosthetic component/screw, i.e., the tool slips from the fitting area, spinning on its own. This problem is very common, especially in components with smaller diameters and that require less torque. 
     In order to prevent the above, there was an attempt to solve such problems, as can be seen in prior art EP0928165B1, which describes an arrangement to be used with a variety of dental screws. 
     Said document describes a tool (or wrench) with a circular cross section wherein the outer ends of the section widen slightly conically. At the same time, these conical outer ends are fastened to the component surface essentially in parallel. 
     Thus, the tool described in said document has two functions, the first function being the tightening function, i.e., the ability to provide torque to fasten the component, and the second function being the ability to fasten the tool in the component; the tool&#39;s capture ability. Furthermore, it is described that the first and second functions are mechanically separated. 
     However, although the tool, as presented, has both capture and fastening functions, it is clear from said document that said tool is not applicable to smaller prosthetic components/screws, i.e., usually smaller than 1.4 mm (ranging from 1.4 to 2.5 mm), such that components/screws smaller in diameter cannot benefit from using said tool. 
     OBJECT OF THE INVENTION 
     Therefore, the present invention aims to solve the problems presented in the prior art by providing a dental tool (wrench) with both capture and fixation functions, and that can also be used with components/screws with reduced diameters (e.g., smaller than 1.4 mm). 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present invention relates to a dental tool for coupling to prosthetic components comprising, at its lower end, a plurality of protrusions and a plurality of recesses, wherein the plurality of protrusions and the plurality of recesses are alternately arranged, each of the protrusions being divided into a first region, a second parallel region, and a third conical region. 
     Furthermore, the present invention relates to a prosthetic component comprising, on its internal surface, a plurality of counterbores and a plurality of projections, wherein the plurality of recesses and the plurality of projections are alternately arranged. 
     The invention further presents a set comprising the dental tool and the prosthetic component, such that the plurality of protrusions fits the plurality of counterbores, and the plurality of recesses fits the plurality of projections. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will now be described in more detail based on an example implementation illustrated in the drawings. The Figs. show: 
         FIG. 1 —perspective view of the end of a prior art hexagonal capture tool, highlighting the capture region; 
         FIG. 2 —perspective view of the end of a prior art capture tool, highlighting the torque region; 
         FIG. 3 —sectional front view of detail A of the hexagonal tool illustrated in  FIGS. 1 and 2  at the moment of torque; 
         FIG. 4 a   —side view of a first embodiment of the dental tool herein; 
         FIG. 4 b   —side view of a second embodiment of the dental tool herein; 
         FIG. 4 c   —side view of a third embodiment of the dental tool herein; 
         FIG. 5 —perspective view of the front end of the dental tool herein; 
         FIG. 6 a   —side view of the end of a first embodiment of the dental tool herein; 
         FIG. 6 b   —front view of the lower end of a first embodiment of dental tool; 
         FIG. 7 a   —side view of the end of a second embodiment of the dental tool herein; 
         FIG. 7 b   —second top view of the lower end of a second embodiment of the dental tool herein; 
         FIG. 8 a   —perspective view of a first embodiment of the prosthetic component/screw herein; 
         FIG. 8 b   —perspective view of a second embodiment of the prosthetic component/screw herein; 
         FIG. 9 a   —top view of the prosthetic component/screw of  FIG. 8   a;    
         FIG. 9 b   —side sectional view of the coupling region of the prosthetic component/screw of  FIG. 8   a;    
         FIG. 10 a   —top view of the prosthetic component/screw of  FIG. 8   b;    
         FIG. 10 b   —a side sectional view of the coupling region of the prosthetic component/screw of  FIG. 8   b;    
         FIG. 11 —partial sectional side view detailing the interaction between the dental tool with the prosthetic component/screw herein; 
         FIG. 12 —sectional side view detailing the interaction between the dental tool with the prosthetic component/screw herein; 
         FIG. 13 —perspective view of the dental tool and component/screw set herein highlighting the capture region; 
         FIG. 14 —perspective view of the dental tool and component/screw set herein highlighting the torque region; 
         FIG. 15 a   —cross-sectional view detailing the interaction between the dental tool with the prosthetic component/screw herein; 
         FIG. 15 b   —enlarged detailed view of  FIG. 15   a.    
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIGS. 1-3  illustrate a hexagonal tool  1  commonly used in the prior art, more specifically, a hexagonal capture tool  1  cooperating with a prosthetic component  2 . 
     As seen in  FIG. 1 , the tip  3  of tool  1  is unable to fully penetrate the length of the internal orifice of component  2  due to the conical portion  5 , such that the bottom region  4  of the internal orifice of component  2  does not contact the tip  3  of tool  1 . This limitation occurs in regions of interference  16  highlighted in  FIG. 1 . 
     Thus, when a torque T is applied (see  FIG. 2 ) to fasten the component  2  in the implant (not shown), note that it is only applied in the upper portion  6  of the internal orifice of component  2 . The contact regions/points  7  are highlighted in said  FIG. 2 . This difference in torque T application makes it so that component  2  experiences deformations and, should the dentist continue to perform the fastening movement, more deformations will occur until such deformations add up and result in the deformation of the tool ridges  1 , so that it will start to rotate on its own, no longer performing torque T. 
     Thus, the tool  1  with conical tip works only for the capture function and to provide only a first torque to lightly fasten the component  2  in the implant. In order to provide the optimal and necessary torque to fasten the component  2  in the implant, the use of a straight-tipped, non-angled tool is ideal, allowing the internal surface of component  2  to fully contact the tip  3  of tool  1 , whereby the application of torque T is made preferably uniformly throughout component  2 . 
     Furthermore,  FIG. 3  shows in enlarged details that the hexagonal tool  1  has only a small contact region  7  actually in contact with the internal surface of component  2  for performing torque T. Thus, in addition to the deformations that occur through the use of tool  1  to tighten component  2 , should the dentist provide a torque T greater than necessary for fastening component  2  in the implant, component  2  tends to deform with the intensity of force applied to it, i.e., the head of component  2  tends to dilate. This deformation is very common in parts small in diameter (smaller than 1.4 mm) that use smaller tools, as such tools support less torque and tend to deform more easily. 
     This deformation is extremely harmful, especially if component  2  needs to be removed for any reason. When the dentist uses a tool to remove the deformed component  2  (dilated head), tool  1  will have difficulty fitting in and, as a result, removing component  2 . 
     Therefore, the present invention aims to provide a dental tool, which performs the function of capturing and fastening a prosthetic component  2  without the need to switch tools, reducing the possibility of defects in the component/screw  2  when applying torque T (dilation of screw head/component) and which can further be used on components with diameters smaller than 1.4 mm. 
       FIGS. 4 a -4 c    illustrate three capture and fastening tool  10  embodiments of the present invention, wherein its lower end  11  has been modified so as to solve the problems presented by the prior art. 
     As best seen in  FIGS. 5-7   b , the lower end  11  of the dental tool  10  comprises a plurality of protrusions  12 , preferably six axial protrusions distributed around its circular perimeter. Said protuberances  12  are divided, from the tip  3  of end  11 , into three subsequent regions; the first region  12 . 1  being equipped with a corner break with the function of facilitate fitting the tool in the component/screw  20 ; a second region  12 . 2  parallel to the longitudinal axis of the wrench, which will be housed inside the component; and a third region  12 . 3  conical/angled in shape. 
     In the embodiment illustrated in  FIGS. 5, 6   a  and  6   b  the recesses  13  extend into the region next to the center of the circular end  3 ′ of the tip  3  of the tool  10 . 
     Optionally and as shown in  FIGS. 7 a  and 7 b   , the lower end  11  of the tool  10  further comprises, alternately with the protrusions  12 , a plurality of recesses  13  also axial in the circular axis of the tool  10 , said recesses  13  having no extensions. Thus, in the embodiment illustrated in  FIGS. 7 a  and 7 b   , the recesses  13  extend only up to an edge  3 ″ of the tip  3  of the tool  10 , not extending in proximity to the center of the circular end  3 ′. 
     This configuration allows protrusions  12  and recesses  13  to have different mechanical functions when the tool  10  is used. 
     However, in order to apply the capture and fastening functions of tool  10 , it is necessary to modify the components/screws  20  to better adapt to the distinct shape of the tool  10 . Therefore, note in  FIGS. 8 a  and 8 b    that the internal surface of the component/screw  20  is comprised of a plurality of projections  22  which form counterbores  21 . 
     As seen in  FIGS. 9 a -10 b   , the counterbore  21  and projections  22  regions of component  20  are alternately distributed and equidistant around the inner surface of the circular section of component  20 . It should be noted that in the embodiment illustrated in  FIGS. 10 a  and 10 b    the internal surface of component  20  is further provided with a small settling platform  23 . 
     Thus, when the tool  10  is inserted into the component  20 , as seen in  FIGS. 11 and 12 , the recesses  13  will couple with the projections  22  while the protrusions  12  will couple with the counterbores  21 , as indicated by arrows A and A′ in  FIG. 11 , respectively. 
     It is important to note that such modification in the shape of both tool  10  and component  20  allows the tool  10  to fully penetrate the internal extension of component  20 , as the conical region  12 . 3  when fitting into counterbores  21  forms a flat axial fitting with the side walls of the projections  22 . This avoids any tendency of defects occurring in tool  10  or component  20  when torque T is applied. 
     With the tool  10  adequately fitted into component  20 , the conical region  12 . 3  will function as a (retention) capture region  14  of component  20 , as highlighted in  FIG. 13 , due to the male/female coupling formed between the conical region  12 . 3  and the counterbores  21  of the internal region of component  20 , temporarily locking the component  20  in the tool  10 . This locking allows the transportation of the component package into the installation site. 
     After transporting the component  20  into the installation site, the dentist needs to perform the necessary torque T to fasten it in an implant (not shown) installed at the patient&#39;s mouth. 
     Due to the alternate combination of the protrusions  12  and the recesses  13 , side walls  15  (seen in  FIGS. 7 a    and  14 ) substantially perpendicular to the longitudinal axis of the tool  10  are formed. 
     Thus, when the tool  10  contacts the component  20 , the side walls  15  align with side walls  22 . 2  substantially perpendicular to the axis of component  20 , which are formed due to the alternately combination of counterbores  21  with the projections  22  (see  FIG. 15 a   ). 
     Thus, when applying torque with rotation movement, the side walls  15  directly contact the entire length of the side walls  22 . 2  forming torque areas  18  as highlighted in  FIG. 14 . 
     As seen in greater detail in  FIGS. 15 a  and 15 b   , the point of contact for applying torque between tool  10  and component  20  does not occur at a single point, but along the entire length of the surfaces of the side wall  15 ,  22 . 2  of tool  10  and component  20 , respectively. 
     Thus, when the dentist performs torque T to fasten the component  20  in the implant, the chances of deforming the head of the component  20  or tool  10  are significantly reduced, which reduces the chances that tool  10  will dilate the head of the component.  20  and, consequently, spin on its own and deform its ridges. 
     Furthermore, since the tool  10  of the present invention does not have the tendency of dilating the head of the component  20 , it is possible to reduce the thickness of the wall of component  20 . This decrease in wall thickness increases the fitting area of the tool  10 , regardless of the size of the component  20  to be fixed. 
     Thus, the same tool  10  can be used for components/screws  20  of different sizes, including those with diameters smaller than 1.4 mm. This is because with the adopted geometry, the radial component of contact force between the parts is smaller, such that a smaller wall thickness is required for the same resistance with the same force applied. 
     Having described a preferred embodiment example, it should be understood that the scope of the present invention covers other possible variations and is limited only by the content of the appended claims, including possible equivalents thereof.