Abstract:
An assembly of denture bridge includes a lingual restoration and a buccal restoration so as to install a denture to the place where a tooth is missing. The buccal restoration has two wings on two ends thereof so as to contact the inside of the nature teeth and the lingual restoration is formed according the mesio-distal side of the lingual side and the occusal surface. Two lingual restorations are connected to the buccal restoration by a screw so as to secured onto the nature teeth. The nature teeth need not to be remove a lot and the denture can be set within a short period of time. The patient needs not to wear a temporary grown.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a bridge assembly that is positioned from the lingual side and the buccal side so that the denture can be well positioned regardless of the shape or form of the nature teeth besides the missing position.  
         BACKGROUND OF THE INVENTION  
         [0002]    A conventional way to positioning a denture  11  is shown in FIG. 1 and has to remove most part of the nature teeth  10  on two sides of the missing position to be parallel or dual-inclined surface form such that the abutment dentures  12  may be mounted to the nature teeth  10  and the denture  11  is positioned at the missing position. The abutment dentures  12  each have a recess  121  so as to mount onto the trimmed nature teeth  10 . The conventional way has to remove part of the nature teeth  10  and this takes a lot of time and effort for the dentists. A local anesthesia is required during the process to trim the nature teeth  10 . Of more importance is that the removal of the nature teeth  10  damages the nature teeth  10 . Besides, a teeth mold is first made according to which the denture is made. A period of waiting time is suffered and a temporary grown is used so as to prevent the trimmed nature teeth  10  from being damaged. Furthermore, it is costly for making the denture and the abutment dentures.  
           [0003]    Another way is to employs a linguobuccal clasp rest which is positioned by a screw. Nevertheless, the clasp rest is only positioned by the screws contacting the nature teeth on the sides of the clasp rest. Therefore, the clasp rest is not secured in the vertical direction so that the screws could be broken when the maxillary mandibles are moved toward each other. The loosened clasp rest may drop downward or dragged to hurt the periodontal membrance, the PDL, and the gingiva. The clasp rest is positioned from the buccal side and the lingual side so that it protrudes form the out sides of the nature tooth that was there. Therefore, the occusal surface of the maxillary mandibles and the buccolingual do not contact the denture in a normal way. The denture is positioned by the splints at the front and the rear sides thereof so that there is no proximal interspace at the nature teeth beside the denture so that the food debris cannot be removed by using the tongue. This results in bad breath.  
           [0004]    Yet another way is disclosure in WO909909 and has to plant the residual root which is positioned by screws. The sides of the nature teeth are to be damaged so as to be engaged with the screws and this way is not satisfied by the market.  
         SUMMARY OF THE INVENTION  
         [0005]    The primary object of the present invention is to provide a bridge assembly that is secured by using a lingual restoration and a buccal restoration. The buccal restoration has two wings at two ends thereof so as to contact the two inner sides of the nature teeth on the two sides of the bridge. The lingual restoration has a undercut which is defined corresponding to the lingual surface, mesio-distal side and occusal surface of the nature teeth on the two sides of the bridge. A screw is used to connect the lingual restoration and the buccal restoration so that the lingual restoration and the buccal restoration can be mounted to the nature teeth without too much removal of the nature teeth.  
           [0006]    Another object of the present invention is to provide a bridge assembly that the patient needs no local anesthesia and the no long-term wearing of temporary grown is required. By this bridge assembly, the patient feels no pain and the bridge assembly is easily to be made.  
           [0007]    The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    [0008]FIG. 1 shows a conventional way to install a denture and the two nature teeth are trimmed;  
         [0009]    [0009]FIG. 2 is an exploded view to show the denture for the maxillary mandible of the present invention;  
         [0010]    [0010]FIG. 3 is another embodiment of the denture for the maxillary mandible of the present invention;  
         [0011]    [0011]FIG. 4 an exploded view to show yet another embodiment of the denture for the maxillary mandible of the present invention;  
         [0012]    [0012]FIG. 5 is a perspective view to show the denture for the maxillary mandible of the present invention as shown in FIG. 4;  
         [0013]    [0013]FIG. 6 is another embodiment of the denture for the maxillary mandible of the present invention;  
         [0014]    [0014]FIG. 7 is a perspective view to show the denture for the maxillary mandible of the present invention, and  
         [0015]    [0015]FIG. 8 shows the arrangement of human teeth. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0016]    Referring to FIGS. 2 and 3, the bridge assembly of the present invention comprises two lingual restorations  25  and a buccal restoration  35 . A connection portion  252  is connected between the two lingual restorations  25  and each lingual restoration  25  has a undercut  251  so as to be mounted onto the nature teeth  45  and  46  located on two sides of the missing position. The shape of the undercut  251  is complimentary to the shape of the contour of the nature teeth  45 ,  46  and mesio-distal side. An engaging notch  451 / 452  is defined in each nature tooth  45 ,  46  because the front occusal surface is inclined and is engaged with an engaging member  254 / 255  in each lingual restoration  25 . This engagement dispenses the force when using the denture and prevents from hurting the gingiva. A first hole  253  is defined in the connection portion  252  between the lingual restorations  25 . A positioning groove  351  is defined in the buccal restoration  35  and is engaged with the connection portion  252  of the lingual restorations  25 . Two wings  352  are formed at two sides of the buccal restoration  35  so as to be engaged with two sides of the nature teeth  45 ,  46 . The positioning groove  351  further includes a threaded hole  353  such that a screw  56  extends through the first hole  253  and is engaged with the threaded hole  353  to connect the two items, A resin filling can be used to fill the notch of the connection area.  
         [0017]    As shown in FIG. 3 which shows the bridge assembly similar that shown in FIG. 2. The only difference is that the first hole  253  is located at the lower edge of the connection portion  252  of the lingual restorations  25 . The threaded hole  353  of the buccal restoration  35  is located corresponding to the position of the first hole  253 .  
         [0018]    As shown in FIGS. 4 and 5 which show yet another embodiment of the present invention and comprises two lingual restorations  2  and a buccal restoration  3 . The lingual restorations  2  are made by metal material and can be used for the situations of missing one tooth, two and four teeth. The first lingual restorations  2  for the situation of two teeth missing are made in one-piece and includes a undercut  211  which is shaped corresponding to the contour of the lingual teeth side of the lingual side and the occusal plane, and a connection portion  212  which is located adjacent to the connection portion  212 . The undercut  211  is mounted to the nature teeth  41  and the connection portion  212  has a threaded hole  213 . For the second lingual restoration  22  in the situation of four teeth missing, besides the undercut  221  and the connection portion  22 , another undercut  224  with a protrusion  223  and a connection portion  225  are formed in the undercut  221  in sequence. The nature teeth  42  has a notch  421  so as to be matched with the protrusion  223  so as to connect the lingual restoration  22  and the nature teeth  42 . For the third lingual restoration  22  for one tooth missing, besides the undercut  231  and the connection portion  232 , a pre-determined number of undercuts  233  are defined in an end of the connection portion  232 . A protrusion is formed on an inside of the undercut located at the side of the third lingual restoration  23 . A notch  431  is defined in the nature tooth  43  so as to be engaged with the protrusion  234  in the undercut  233 .  
         [0019]    For the first buccal restoration  31  includes two positioning grooves  311 ,  312  and a threaded hole  313  is defined in the two positioning grooves  311  so as to cooperate with the two respective threaded holes  213  in the connection portion  212  and the threaded hole  226  in the connection portion  222  of the second lingual restoration  22 . Two wings  314  extend from two ends of the first lingual restoration  31  and contact against the insides of the two nature teeth  42 . The first lingual restoration  31  is engaged with the nature teeth and the two connection portions  212 ,  222  are inserted in the positioning grooves  311 ,  312 . Two screws  51 ,  52  threadedly engage with the two threaded holes  213 ,  313  of the first lingual restoration  21  and the buccal restoration and the two threaded holes  226 ,  313  of the second lingual restoration  21  and the first buccal restoration  31  from inside of the mouth toward outside, the wings  314  of the first buccal restoration  31  contact the nature teeth  41 ,  42 . This ensures the first lingual restoration  21 , the second lingual restoration  22  and the first buccal restoration are firmly connected to the nature teeth  41 ,  42  without interspace as shown in FIG. 5. For the second buccal restoration  32  for the place where four teeth are missing, extra dentures are needed because the space of the missing teeth is large. The connection by the screw  53  makes the second lingual restoration  22  and the second buccal restoration each have a wing  322  at one end thereof so as to contact the nature teeth  42 ,  43 . The second buccal restoration cannot pass through the area where the teeth are missing so that no intersapce is defined as shown in FIG. 5. For the third buccal restoration  33  for the place where one tooth is missing, the third buccal restoration  33  has two wings  331  at two ends thereof and the two wings  331  contact the nature teeth  43 ,  44 . The difference from the first buccal restoration  31  is that the positioning grooves  332  at the two sides thereof become a single space such that the third buccal restoration  33  can be connected to the connection portion  232  of the third lingual restoration  23  by the single space  332 . The wings  331  contact the adjacent nature teeth  43 ,  44  and the screw  54  makes the third lingual restoration  23  to the third buccal restoration  33  be secured to the nature teeth  43 ,  44 . Another screw  55  connects the third lingual restoration and the second buccal restoration  32  together as shown in FIG. 5.  
         [0020]    [0020]FIGS. 6 and 7 show the buccal restoration  3  has positioning grooves  311 , wings  314  and the threaded hole  313 . The lingual restoration  2  has a first lingual restoration  21  and a undercut  211  is defined from inside of the first lingual restoration  21 . The connection portion  212  is connected to the positioning grooves  311  of the buccal restoration  3  can be connected with each other by a screw  56 . The undercut  211  is matched with the occusal surface of the nature teeth and the buccal restoration  3  has wings  314  on its two ends and the wings  314  contact the nature teeth  41 ,  42 . A filling  50  can be used to fill the notch of the connection area of the screw  56 .  
         [0021]    The lingual restorations and the buccal restoration are connected by the screw and the lingual restorations have an undercut to match with the nature teeth such that the force can be dispensed by the nature teeth. This protects the screw and the denture which is not descended or hurts the gingiva. The damage for the nature teeth is reduced to 0.2 mm to 0.5 mm only so that the time consuming is effectively reduced and no local anesthesia is necessary. The buccal restoration has a contour that is matched with the curved contour of the inside of the nature teeth (mesio-distal side). The two wings of the buccal restoration are engaged with the contour of the nature teeth and the occusal plane can be maintained. When using the teeth and the dentures, the screw is used only for connection and does not completely bear the force so that it improves the shortcomings of the conventional dentures.  
         [0022]    While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.