Abstract:
A Modular Tooth Veneer system, comprising at least one MTV unit having a cephalic body, an elongate buccal body extending from the cephalic body, and a lingual body extending from the cephalic body, the lingual body being spaced a distance from the buccal body.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to prefabricated modular tooth veneers installed on an oral support frame or on pre-prepared teeth. More specifically, the present invention provides a system, using modular tooth veneers, for producing an oral prosthetic in minimal time. (This is not the place for specific variations—just the general field)  
       BACKGROUND OF THE INVENTION  
       [0002]     Creating an aesthetically pleasing oral prosthesis, comprising one or more prosthetic teeth on a support frame, is an exacting process. After separately preparing a wide variety of dentin paste colors from powders, a laboratory technician must apply each color separately to the support frame with a fine brush, building each individual tooth with appropriate shape, color, depth and shade.  
         [0003]     The subsequent firing to harden, herein cure, the dentin paste, shrinks each cured tooth by 20% to 30%. After curing, the shape, color and shade of each tooth must be restored in multiple time-intensive application steps; each step requiring firing and often accompanied by grinding, polishing and/or application of enamel.  
         [0004]     As used herein, “dentin” is the bonding material used in bonding the tooth to the frame, and building the tooth shape. “Enamel”, as used herein, is a material used on the exterior of the tooth.  
         [0005]     To reduce the number of steps, U.S. Pat. No. 6,250,926 to Foser et al and assigned to Ivoclar Vivadent AG, teach a preshaped tooth veneer that is adhered only to the buccal and cephalic support frame surfaces, thereby providing inadequate bonding strength, often leading to failure due to the stress of chewing.  
         [0006]     Additionally, U.S. Pat. No. 6,250,926 fails to specify critical structural requirements for posterior veneers, thereby limiting its teaching to the frontal teeth; e.g. incisors and canines. Additionally, the veneers are limited to approximate hand sculpted tooth shapes, rather than precision tooth models; the sculpted tooth shapes requiring additional steps to achieve tooth shape.  
         [0007]     Moreover, U.S. Pat. No. 6,250,926 teaches veneers that are manufactured exclusively in precious metal ceramics, thereby ignoring the greater part of the market dealing in prostheses from non-precious metal, zirconium, and aluminum oxide ceramics as well as wax, composite and acrylic.  
         [0008]     As used herein, an MTV unit in a given material, for example zirconium, is installed using compatible dentin and/or enamels, on a support frame of a compatible material, for example zirconium.  
       SUMMARY OF THE INVENTION  
       [0009]     An aspect of an embodiment of the present invention provides a prosthetic system comprising multiple precisely modeled Modular Tooth Veneer (MTV) units that do not shrink during curing, reducing the number of steps dedicated to shaping oral prosthetic teeth. In addition, MTV teeth are offered in multiple units, each duplicating the type, color, and shade of real human tooth, additionally reducing number of steps required to achieve appropriate color and shade in the finished prosthesis.  
         [0010]     In an exemplary embodiment, MTV units are typically provided in wax, acrylic, composite and/or a variety of ceramic MTV units, each with appropriate dentin and support frames, so that prostheses can be rapidly manufactured in virtually any material. Optionally an identification code is provided with each MTV unit, identifying shape, size, color and material so that by matching the wax unit codes in a mockup demonstration model, a laboratory can readily produce a final ceramic prosthesis, for example, by using ceramic teeth with the same codes as those of the wax MTV units.  
         [0011]     Additionally, all MTV units, whether frontal or posterior units, are designed to maintain substantial stability and strength during the curing process, ensuring longevity in the finished prosthetic. As used herein, “frontal unit” refers to an MTV unit comprising one of the six frontal tooth types including incisors and canines of either the upper or lower jaws. As used herein, “posterior unit” refers to an MTV unit comprising at one of the eight posterior tooth types including pre-molars and molars of either the upper or lower jaws.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     Exemplary non-limiting embodiments of the invention described in the following description, read with reference to the figures attached hereto. In the figures, identical and similar structures, elements or parts thereof that appear in more than one figure are generally labeled with the same or similar references in the figures in which they appear. Dimensions of components and features shown in the figures are chosen primarily for convenience and clarity of presentation and are not necessarily to scale. The attached figures are:  
         [0013]      FIG. 1  is a frontal MTV unit, in accordance with an embodiment of the present invention;  
         [0014]      FIG. 2  is a side cutaway view of the MTV unit of  FIG. 1 , installed on a support frame, in accordance with an embodiment of the present invention;  
         [0015]      FIGS. 3 and 4  are pre-molar and molar MTV units, respectively, in accordance with an embodiment of the present invention;  
         [0016]      FIG. 5  is a prepared plaster positive in the process of receiving MTV frontals, in accordance with an embodiment of the present invention; and  
         [0017]      FIG. 6  is vacuum-formed demonstration prosthesis, prepared for insertion in a recipient&#39;s mouth, in accordance with an embodiment of the present invention. 
     
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS  
       [0018]     As seen in  FIG. 1 , a frontal MTV  100  comprises a cephalic body  158  from which extend a buccal body  150  and a lingual body  184 . MTV units  100  are typically offered in wax, acrylic, ceramic and composite so that a finished prosthesis in acrylic, ceramic or composite can be easily fashioned once the recipient has approved a wax demonstration mockup.  
         [0019]     In an exemplary embodiment, each MTV unit  100  has a lingual body that provides substantial bonding strength. Additionally, the buccal  150  and lingual  184  bodies of the MTV form an angle that varies in obliquity to provide substantial stability in each type of frontal and posterior MTV  100 .  
         [0020]     As used herein, “lingual body”, refers to the posterior, lingual and/or occlusal portion of the frontal and posterior teeth. Further, as used herein, “buccal body” refers to labial and buccal tooth portions of the frontal and posterior teeth.  
         [0021]     Each MTV  100  unit is already cured, reducing the amount of shrinkage during firing and the associated steps in compensating for the shrinkage. Additionally, the present invention provides multiple common shapes and sizes of MTV  100  in each tooth type so that an MTV  100  can be chosen that closely approximates the tooth being replaced. Further, the shape of each MTV  100  is made using a precision mold of a human tooth, for example using tooth casts, rapid prototyping, and/or three dimensional jaw or tooth scans. Additionally, MTV units will be offered that are based upon existing tooth types, shapes, sizes and color existing already on the market in full dentures. The present system further envisions providing precision MTV units that vary according to gender, for example with female incisor teeth, for example, being generally more rounded than male incisor teeth.  
         [0022]     In addition to providing an MTV  100  unit with precise shape and color, each MTV  100  unit incorporates three or more shaded volumes, providing a pre-formed veneer that requires few steps to modify shading. In addition to reducing the many steps involved in fashioning a prosthesis, the MTV  100  veneer reduce reliance on specially trained artisans that are typically used in prosthetic fabrication of prior art oral prostheses, thereby further reducing the end product cost.  
         [0023]     The MTV system additionally includes demonstration kits that are distributed to operators, the demonstration kits including at least one base jaw model, for example a plastic version of a base model  500  seen in  FIG. 6 , and multiple common shapes and sizes of MTV  100  in each tooth type that readily connect and disconnect from base model  500 . Alternatively or additionally, catalogues of all available MTV  100  units are provided to the operator. Demonstration kits and/or catalogues allow the operator to easily provide a mockup demonstration, obtain recipient input on preferred MTV  100  units, and a code system by which changes in preferred MTV  100  units can be easily communicated with the laboratory.  
         [0024]     As used herein, oral prostheses comprise wax, acrylic, composite and/or ceramic MTV units and correspondingly appropriate dentin and support frames. Further, ceramic prostheses comprise ceramic MTV units and dentin that are appropriate for installation with support frames that include, inter alia, zirconium oxide, aluminum oxide, titanium, precious metal and non-precious metal, for example chrome cobalt.  
         [0025]     As used herein, acrylic materials refers to any prosthesis formed from a combination of acrylic powder polymer and a monomer liquid. As used herein, composite materials comprise any material compose of glass or ceramic particles having light sensitive filler that, upon exposure to light, cures the composite material.  
         [0026]     Optionally, an operator, for example a dentist has the option to provide the recipient with a finished prosthetic, for example in acrylic or composite MTV  100  units on an appropriate acrylic support frame, without sending the wax mockup to the laboratory. This is possible because acrylic and composite MTV  100  units, unlike ceramic, can be cured without firing.  
         [0027]     Alternatively or additionally, the operator may opt to apply MTV unit  100 , for example from acrylic or composite, directly to a pre-pared tooth stump, using the appropriate dentin to bond MTV  100  unit to the stump.  
         [0028]     MTV  100 , shown in a cutaway view in  FIG. 2 , typically includes translucent volumes that impart realistic shading to MTV  100  and reduce the number of steps required in applying colors to MTV. For example a cephalic central volume  210  is substantially transparent and comprises a height of approximately 1 millimeter. A cephalic frontal volume  212  is between 60% and 70% translucent; a mid-buccal volume  230  is 30% to 40% translucent, a lower buccal volume  260  is 80% transparent and a lingual volume  240  is 80% translucent.  
         [0029]     To reduce shrinkage during firing, bonding dentin  140  and  142  have a coefficient of expansion that is similar to, or duplicates, the expansion coefficient of support frame  130  and MTV  100 . However, even with appropriate coefficient of expansion, shrinkage of 20% shrinkage or more occurs in bonding dentin  140  and  142  during firing and curing, resulting in misalignment and instability in cured MTV  100  unit. To this end, lingual body  184  and an offset tab  156  typically cover at least 20% of a support frame  130 , thereby stabilizing MTV  100  during firing and imparting substantial strength in cured MTV  100 .  
         [0030]     In an exemplary embodiment, frontal MTV  100  units include lingual body  184  and buccal body  150  that join at an angle  192  that is between 20-25 degrees, depending upon the shape of frame  130  and/or the shape and size of the recipient&#39;s mouth. Angle  192  provides further stability of MTV  100 , for example during firing and upon installation in the recipient mouth.  
         [0031]     In an exemplary embodiment, lingual body  184  includes lingual offset tab that has a smaller transverse thickness than lingual body  184 . Similarly, buccal body  150  includes a buccal offset tab  154  that has a smaller transverse thickness than buccal body  150 . The overlay of bonding dentin  140  and  142  on lingual  156  and buccal  154  tabs, respectively, provides additional structural reinforcement in the bond between MTV  100  and support frame  130 .  
         [0032]     All structural features, for example, shape, coloring, and shading are applicable to MTV  100  units in wax, ceramic, acrylic and composite. Additionally, lingual  156  and buccal  154  tabs are applicable to units in ceramic, acrylic and composite and, optionally, to MTV  100  units in wax.  
         [0033]     In an exemplary embodiment, ceramic shell MTV  100  units are provided in a variety of ceramic materials whose coefficient of expansion are adapted to a variety of support frames; including, inter alia, zirconium oxide frame aluminum oxide frame, titanium frame, precious metal frame and non-precious metal (chrome cobalt).  
         [0034]     As in prior art prosthetics, frame  130  in ceramic is typically coated using a thin layer of opaque ceramic  132 , so frame  130  compliments the color of MTV  100 . Additionally, colored dentin ceramic material  140  and  142  comprising a ceramic paste or wet ceramic powder is also typically colored to compliment the color of MTV  100 . The firing temperature to cause bonding dentin  140  and  142  to cure is typically less than the thermal deformation temperature of MTV  100 , for example by 50 degrees Celsius. However, the difference of 50 degrees may be increased or decreased depending on the materials used.  
         [0035]     Typically, enamel coloring is added to buccal body  150 , lingual  184  and cephalic  158  bodies and extend coloring onto buccal bonding dentin  142  and lingual bonding dentin  140  providing a natural translucent-to-opaque gradient.  
         [0036]     When multiple MTV  100  units are used, for example, in a full mouth prosthetic, enamel coloring is typically added to all MTV  100  units once MTV units  100  have attained an appropriate size, shape and color. Enameled MTV units  100  provide the recipient with an aesthetically pleasing prosthesis, including posterior MTV premolar  200  units, seen in  FIG. 3  and MTV molar units  300 , seen in  FIG. 4 .  
         [0037]     As used herein, support frame  130  installs over the patient jaw tissue as a denture, or is modified to be installed in conjunction with one or more implants posts (not shown) that are implanted, for example, in the recipient jaw.  
         [0038]     In an exemplary embodiment, premolar  200  and molar  300  MTV units include buccal body  150 , cephalic body  158  and lingual body  184  and uses similar translucent volumes to that of lingual body  184  cephalic  158  bodies of MTV  100  ( FIG. 2 ) to achieve appropriate shading.  
         [0039]     In an exemplary embodiment, angle  192  of pre molar  200  ( FIG. 3 ) is typically between 65-80 degrees, depending upon the angle of the support frame and/or the jaw structure of the recipient mouth.  
         [0040]     Further angle  192  of molar  300  (seen in  FIG. 4 ) is typically between 65-80 degrees, depending upon the angle of the support frame and/or the jaw structure of the recipient mouth.  
         [0000]     Method  
         [0041]     Typically, the operator, for example, a dentist, will take a mouth impression, that is sent to a laboratory that forms a positive plaster impression  400  ( FIG. 5 ). The laboratory grinds a frontal portion  440  and bonds MTV wax shells  420 ,  422 ,  426  and  428  to an impression mock-up  460 . An MTV shell  424  is shown in the process of being attached to a grounded base  484 , typically using wax bonding material  486 , known in the art.  
         [0042]     Each of wax shells  420 ,  422 ,  424 ,  426  and  428  include a code that identifies the type of tooth, the side, shape and color so that matching the recipient&#39;s natural teeth is readily accomplished to from mock-up  460 .  
         [0043]     As used herein, “side” refers to the buccal body depth measured along a cross sectional ray that is perpendicular to the midpoint of a ray running through the longitudinal axis of the buccal body.  
         [0044]     Additionally, for example, to allow the operator to call the laboratory and identify alternative shapes or colors preferred by the recipient, the identification code is recorded in a recipient file that is available to the operator. As used herein, “identification code” includes any combination of numbers, shapes, symbols, and colors that identify the type, color, shape and shade of MTV unit  424 ; with such identification code being included on MTV  100  unit ( FIG. 1 ), mockup  486  and or packaging associated therewith.  
         [0045]     Typically, the operator fills MTV shell  424  with elastic composite acrylic  560  and puts shell  424  in the patient mouth to demonstrate the shape and size of frontal  520 ,  522 ,  524 ,  526  and  528  and posterior  510  teeth.  
         [0046]     At the request of the recipient, the operator provides alternative teeth  520 ,  522 ,  524 ,  526  and  528 , based on catalogue or demonstration kit MTV units  100  noted above. Following recipient approval, the operator uses the identification code of each replaced unit  520 ,  522 ,  524 ,  526  and  528  to apprise the laboratory of the identification codes of the teeth to be substituted on wax mockup  460 .  
         [0047]     In cases where the operator manually makes manual modifications to mock-up  460 , for example grinding units  520 ,  522 ,  524 ,  526  and/or  528 , the operator sends mock-up  460  to the laboratory along with notes pertaining to codes changes associated with alternative units  520 ,  522 ,  524 ,  526  and/or  528 .  
         [0048]     In an exemplary embodiment, the laboratory uses the revised wax mockup  460  ( FIG. 4 ), composite shell  500 , and/or unit identification code changes, to provide the operator with a new vacuum-formed frontal composite shell  500  to demonstrate in the recipient mouth.  
         [0049]     Once the recipient is satisfied with the shape, size and coloring of composite shell  500 , the operator typically puts an acrylic paste  560  into shell  500  and makes a temporary prosthesis for the recipient using methods known in the art. Alternatively, the laboratory provides a temporary prosthesis for the recipient, using wax mockup  460  ( FIG. 4 ) as a model using methods known in the art.  
         [0050]     After approval of demonstration mockup  500 , the identification codes of each of teeth  520 ,  522 ,  524 ,  526  and  528  are used to choose appropriate MTV units  100  ( FIG. 1 ) in acrylic, composite and ceramic that duplicate the type, size, coloring and shape of demonstration mock up  500 .  
         [0051]     Additionally, the many structure reinforcements noted above, for example tabs  154  and  156  and lingual body  184  ( FIG. 1 ), in ceramic, composite or acrylic MTV  100  units that replace wax MTV units  420 ,  422 ,  424 ,  426  and  428  ( FIG. 4 ) foster proper positioning in spite of shrinkage during firing and structurally strong.  
       EPILOGUE  
       [0052]     The invention has been described with respect to wax, ceramic, acrylic and composite materials citing but a few of the many options that are available.  
         [0053]     The myriad of materials, their manufacturers and the methods for producing wax or composites MTV  100  units and their corresponding bonding dentin  140  and  142  and support frames  130  are well known to those familiar with the art.  
         [0054]     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. Also, combination of elements from variations may be combined and single elements may be used. Such variations and modifications, as well as others that may become apparent to those skilled in the art are intended to be included within the scope of the invention, as defined by the appended claims.  
         [0055]     The terms “include”, “comprise” and “have” and their conjugates as used herein mean “including but not necessarily limited to.” 
         [0056]     It will be appreciated by a person skilled in the art that the present invention is not limited by what has thus far been described. Rather, the scope of the present invention is limited only by the following claims.