Abstract:
A computerized method for coloring a porcelain tooth includes a color difference comparison step, a first computer aided process, and a second computer aided process, for precisely controlling the color of the porcelain tooth. Each parameter is obtained from data comparison. The first computer aided process forms a first layer on the surface of the porcelain tooth and then and the second computer aided process forms a second layer on the first layer by way of computer aided manufacturing (CAM) according to the color difference comparison step. Because of CAM, the method does not require an experienced operator. Therefore, it may reduce labor cost, human error, and ceramic powder consumption. The method may thus save cost, improve production efficiency, and shorten delivery time of the porcelain tooth product.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a computerized method for coloring a porcelain tooth, and more particularly, to a computerized method for coloring porcelain tooth including a color difference comparison step, a first computer aided process, and a second computer aided process. 
         [0003]    2. The Prior Art 
         [0004]    Referring to  FIG. 1 , a conventional porcelain tooth structure  1  includes a porcelain tooth  11 , a bottom color layer  13 , a dentine layer  15 , and an enamel layer  17 . 
         [0005]      FIG. 2  is a flow chart showing a conventional method for coloring a porcelain tooth. As shown in  FIG. 2 , the conventional method for coloring the porcelain tooth includes the following steps: manually mixing dyes S 11 , manually spreading base color coating S 13 , heat drying the base color coating S 15 , high-temperature sintering the base color coating S 17 , manually spreading dentine coating S 19 , heat drying the dentine coating S 21 , high-temperature sintering the dentine coating S 23 , manually spreading enamel coating S 25 , heat drying the enamel coating S 27 , and high-temperature sintering the enamel coating S 29 . 
         [0006]    In the conventional method, due to the manual spreading manner, every coating needs to be mixed, spread, and adjusted by man power. After the coating is sintered, the color appearance of the porcelain tooth depends on the selected dyes. Therefore, it needs experienced operators to color the porcelain tooth, which demands a relatively high labor cost. Moreover, manual coloring taking a longer time to finish the job and thus it takes a longer time to deliver. Human errors may be more frequently occurred if the operator is not experienced. Thus, the conventional manual method has lower production efficiency and a higher cost. 
       SUMMARY OF THE INVENTION 
       [0007]    A primary objective of the present invention is to provide a computerized method for coloring porcelain tooth that overcomes the disadvantages mentioned above. The computerized method for coloring porcelain tooth according to the present invention sequentially includes a color difference comparison step, a first computer aided process, and a second computer aided process, for precisely controlling the color of the porcelain tooth. The color difference comparison step may accurately calculate the coating proportion and the coating thickness of each position on the surface of the porcelain tooth according to the color data. The first computer aided process forms a first layer on the surface of the porcelain tooth by way of computer aided manufacturing (CAM) according to the coating proportion and the coating thickness calculated by the color difference comparison step. The second computer aided process may form a second layer on the first layer by way of CAM according to the coating proportion and the coating thickness calculated by the color difference comparison step. Moreover, the above steps are accomplished by a computerized coloring device, a drying device, and a high temperature furnace. 
         [0008]    The computerized method for coloring the porcelain tooth according to the present invention makes the manufacturing process standardized and computerized by way of CAM. Thus, the operators do not need to be very experienced, and therefore it may reduce labor cost and human error. Besides, the color of the porcelain tooth may be precisely controlled by way of CAM. Thus, the ceramic powder consumption is reduced, and then it further saves cost, improves production efficiency, and shortens delivery time of the porcelain tooth. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The present invention will be apparent to those skilled in the art by reading the following detailed description of preferred embodiments thereof, with reference to the attached drawings, in which: 
           [0010]      FIG. 1  is a schematic view showing a conventional porcelain tooth structure; 
           [0011]      FIG. 2  is a flow chart showing a conventional method for coloring porcelain tooth; 
           [0012]      FIG. 3  is a flow chart showing a computerized method for coloring a porcelain tooth according to a first embodiment of the present invention; 
           [0013]      FIG. 4  is a flow chart showing the first computer aided process of the computerized method for coloring the porcelain tooth according to the first embodiment of the present invention; 
           [0014]      FIG. 5  is a flow chart showing the second computer aided process of the computerized method for coloring the porcelain tooth according to the first embodiment of the present invention; 
           [0015]      FIG. 6  is a flow chart showing another computerized method for coloring the porcelain tooth according to a second embodiment of the present invention; 
           [0016]      FIG. 7  is a schematic view showing a computerized coloring device according to the present invention; 
           [0017]      FIG. 8  is a schematic view showing a porcelain tooth structure according to the first embodiment of the present invention; and 
           [0018]      FIG. 9  is a schematic view showing a porcelain tooth structure according to the second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]    Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
         [0020]      FIG. 3  is a flow chart showing a computerized method for coloring a porcelain tooth according to a first embodiment of the present invention. As shown in  FIG. 3 , the computerized method for coloring the porcelain tooth according to the present invention sequentially includes the steps of: a color difference comparison step S 30 , a first computer aided process S 40 , and a second computer aided process S 50 , for precisely controlling the color of the porcelain tooth by way of computer aided manufacturing. The color difference comparison step S 30  accurately calculates coating proportion and coating thickness on each position of the porcelain tooth according to color data. The first computer aided process S 40  forms a first layer on the surface of the porcelain tooth by way of computer aided manufacturing (CAM) according to the coating proportion and the coating thickness calculated by the color difference comparison step S 30 . The second computer aided process S 50  forms a second layer on the first layer by way of CAM according to the coating proportion, the coating thickness, and operating parameters calculated by the color difference comparison step S 30 . 
         [0021]    The color data may be provided by a dentist or a porcelain tooth designer, and then the aforementioned steps are used to precisely control colors by way of CAM, so as to achieve the predetermined color of the porcelain tooth. In addition, the color difference comparison step S 30 , the first computer aided process S 40 , and the second computer aided process S 50  are accomplished by a computerized coloring device, a drying device, and a high temperature furnace. 
         [0022]      FIG. 4  is a flow chart showing the first computer aided process S 40  of the computerized method for coloring the porcelain tooth according to the first embodiment of the present invention. As shown in  FIG. 4 , the first computer aided process S 40  includes the steps of: a tooth positioning step S 41 , a first computerized spraying process S 43 , a heat drying step S 45 , and a high-temperature sintering step S 47 . The tooth positioning step S 41  fixes the porcelain tooth in the computerized coloring device, detects a three dimensional contour of the porcelain tooth, and locates spraying positions on the porcelain tooth. The first computerized spraying process S 43  sprays a first layer of coating onto the spraying positions on the surface of the porcelain tooth by way of CAM. The coating proportion and the coating thickness are calculated by the color difference comparison step S 30  and the spraying position is determined by the tooth positioning step S 41 . After the first computerized spraying process S 43 , the heat drying step S 45  takes the porcelain tooth sprayed with the first layer of coating out of the computerized coloring device, puts the porcelain tooth into the drying device, and dries the first layer of coating according to a standard drying process. After the heat drying step S 45 , the high-temperature sintering step S 47  takes the porcelain tooth out of the drying device, puts the porcelain tooth into the high temperature furnace and sinters the first layer of coating in high temperature according to a standard sintering process, so as to form the first layer. The first layer of coating may be a base color coating or a mixed coating of a base color coating and a dentine coating. 
         [0023]    Referring to  FIG. 5 , a flow chart showing the second computer aided process S 50  of the computerized method for coloring the porcelain tooth according to the first embodiment of the present invention is illustrated. As shown in  FIG. 5 , the second computer aided process S 50  includes the steps of: a tooth positioning step S 51 , a second computerized spraying process S 53 , a heat drying step S 55 , and a high-temperature sintering step S 57 . After the first computer aided process S 40 , the tooth positioning step S 51  fixes the porcelain tooth having the first layer in the computerized coloring device, detects a three dimensional contour of the porcelain tooth, and locates a plurality of spraying positions on the first layer of the porcelain tooth. The second computerized spraying process S 53  sprays a second layer of coating on the spraying positions on the surface of the first layer by way of CAM. The coating proportion and the coating thickness are calculated by the color difference comparison step S 30  and the spraying position is determined by the tooth positioning step S 51 . After the second computerized spraying process S 53 , the heat drying step S 55  takes the porcelain tooth having the second layer of coating out of the computerized coloring device, puts it into the drying device and dries the second layer of coating according to the standard drying process. After the heat drying step S 55 , the high-temperature sintering step S 57  takes out the porcelain tooth from the drying device, puts it into the high temperature furnace and sinters the second layer of coating in high temperature according to the standard sintering process, so as to form the second layer. The second layer of coating is a mixed coating of a dentine coating and an enamel coating when the first layer of coating is the base color coating, and the second layer of coating is an enamel coating when the first layer of coating is a mixed coating of the base color coating and the dentine coating. 
         [0024]      FIG. 6  is a flow chart showing a computerized method for coloring a porcelain tooth according to a second embodiment of the present invention. As shown in  FIG. 6 , the computerized method for coloring the porcelain tooth according to the second embodiment of the present invention includes a color difference comparison step S 60  and a computer aided process S 70 . The computer aided process S 70  includes a tooth positioning step S 71 , a computerized spraying process S 73 , a heat drying step S 75 , and a high-temperature sintering step S 77 . The color difference comparison step S 60  is the same method as the color difference comparison step S 30  of  FIG. 3 , and the tooth positioning step S 71  is the same method as the tooth positioning step S 41  of  FIG. 4 . 
         [0025]    The computerized spraying process S 73  sprays a dye layer of coating on the spraying positions on the surface of the porcelain tooth by way of CAM. The coating proportion and the coating thickness are calculated by the color difference comparison step S 60  and the spraying position is determined by the tooth positioning step S 71 . After the computerized spraying process S 73 , the heat drying step S 75  takes the porcelain tooth having the dye layer of coating out of the computerized coloring device, puts it into the drying device and dries the dye layer of coating according to the standard drying process. After the heat drying step S 75 , the high-temperature sintering step S 77  takes out the porcelain tooth from the drying device, puts it into the high temperature furnace and sinters the dye layer of coating in high temperature according to the standard sintering process, so as to form the dye layer. The dye layer of coating is a mixed coating of a base color coating, a dentine coating and an enamel coating. 
         [0026]    The steps included in  FIGS. 4-6 , the heat drying steps S 45 , S 55 , and S 65  have a range of a drying temperature of 30-150 degrees Celsius, and the high-temperature sintering steps S 47 , S 57 , and S 67  have a range of a sintering temperature of 700-2000 degrees Celsius. The method for coloring the porcelain tooth may be computerized and standardized by using the steps S 41 -S 57  or S 71 -S 77 . 
         [0027]      FIG. 7  is a schematic view showing the computerized coloring device  2  according to the present invention. The computerized coloring device  2  according to the present invention includes a spraying process unit  20  and a control unit  30 . The spraying process unit  20  includes a tooth fixing base  21 , a coating cartridge  23 , a nozzle set  25  and a moving positioning system  27 . The porcelain tooth is fixed in the tooth fixing base  21 . The coating cartridge  23  has plurality sets of coatings (not shown). The nozzle set  25  is connected with the coating cartridge  23 . The nozzle set  25  uses at least one of a thermal sublimation manner, a piezoelectricity manner, and a mixing manner to spray the coatings onto the porcelain tooth. The moving positioning system  27  is a robot arm with at least one sensor (not shown), connected with the coating cartridge  25  and electrically connected with the control unit  30 . The moving positioning system  27  locates the porcelain tooth in coordination with the control unit  30  for accurately controlling the position and the angle of the nozzle set  25 . The coatings are at least one of a metal ion aqueous solution, a metal ion oily solution, and an oxide slurry. 
         [0028]    The control unit has a control software for controlling the spraying process unit  20 . The control software has a positioning function, a data comparison function, and a performing function. The positioning function executes the three dimensional locating to the porcelain tooth in coordination with the moving positioning system  27 , so as to precisely control the nozzle set  25  and the position and the angle of the moving positioning system  27 , and therefore accurately colors the porcelain tooth. The data comparison function performs the color difference comparison step S 30 . The performing function performs the first computer aided process S 40 , the second computer aided process S 50 , and the computer aided process S 70  based on the positioning function and the data comparison function. 
         [0029]      FIGS. 8 and 9  are views showing a porcelain tooth according to the first embodiment and the second embodiment of the present invention, respectively. Referring to  FIG. 8 , the porcelain tooth structure  6  according to the first embodiment of the present invention includes a porcelain tooth  61 , a first layer  63 , and a second layer  65 , accomplished by the method of  FIGS. 3-5 . Referring to  FIG. 9 , the porcelain tooth structure  7  according to the second embodiment of the present invention includes a porcelain tooth  71  and a dye layer  73 , accomplished by the method of  FIG. 6 . 
         [0030]    Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.