JPH0414982B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for obtaining a denture base using a thermoplastic resin. The present invention relates to an apparatus for manufacturing an excellent thermoplastic resin denture base by obtaining a good resin flow.

[Prior Art] In recent years, methods have been developed in which engineering plastics, which have excellent mechanical strength and safety, are used as denture base materials. Examples include polycarbonate denture bases made by injection molding, polysulfone denture bases, and the like. However, the injection molding method requires an expensive injection molding machine to form the denture base.

On the other hand, as a method for easily molding a thermoplastic resin denture base using an inexpensive compression molding machine, a preform similar to the denture base to be manufactured is heated and softened on the lower plaster mold, and then compression molded. Methods to do this are well known.

As equipment for such a compression molding method, Utility Model Application Publication No. 59-57919 discloses a thermostatic chamber for heating and softening thermoplastic resin, a guide for moving the lower plaster mold to below the upper plaster mold, and compression molding. A denture base making device that combines machines is shown.

[Problems to be Solved by the Invention] However, in this device, since the heated and softened thermoplastic resin is taken out of the constant temperature room and molded, it takes time to move the plaster mold before molding.
As a result of the cooling of the thermoplastic resin, drawbacks such as thickening of burrs appear. To prevent this, in order to ensure sufficient flow of thermoplastic resin during molding,
If the heating temperature of the thermoplastic resin is raised, not only will the surface of the thermoplastic resin burn, but the thermoplastic resin will flow down from the convex parts of the plaster mold, resulting in a lack of thermoplastic resin in the alveolar area during molding, and molding defects. There is a disadvantage that it occurs.

[Means for Solving the Problems] Therefore, in order to improve the drawbacks of the above-mentioned conventional techniques and obtain a good denture base, the present inventors developed a method in which a preformed thermoplastic resin was heated and softened in a constant temperature room, and then , developed a device that can immediately perform compression molding and, as a result, produce a good denture base.
This led to the present invention.

That is, according to the present invention, in an apparatus for obtaining a denture base by placing a heat-softened thermoplastic resin between upper and lower split molds for denture base molding and compression molding the same, in the same constant temperature room, Equipped with means for heating thermoplastic resin and means for pressing thermoplastic resin softened by heating, the thermostatic chamber is divided into an upper chamber and a lower chamber by a partition plate inserted between the upper and lower molds. A denture characterized in that, as means for heating the resin, the upper chamber is equipped with a heater that heats the artificial tooth to a temperature that does not cause thermal deformation, and the lower chamber is equipped with a heater that heats the thermoplastic resin to a temperature that can soften it. A floor forming device is provided.

As the heating means for the thermoplastic resin in the present invention, hot air heating means or infrared heating means are employed. When molding a denture base, the ambient temperature of the upper mold (hereinafter referred to as the upper flask) in which the artificial teeth are filled is set to a temperature at which the artificial teeth are not deformed by heat, and then placed on the lower mold (hereinafter referred to as the lower flask). It is necessary to adjust the ambient temperature of the upper and lower flasks to different temperatures, such as the temperature at which the thermoplastic resin flows during molding. For this reason, in the hot air heating means, a method is used in which a partition is inserted between the upper flask and the lower flask to soften the thermoplastic resin, and then the partition is moved to perform pressing.

On the other hand, in the infrared heating means, an infrared heater for keeping the upper flask warm and an infrared heater for heating the thermoplastic resin in the lower flask are arranged between the upper and lower flasks set in the press section, so that the thermoplastic resin is softened. Molding can be performed by removing the rear heater from the press section.

[Examples] Hereinafter, examples of the present invention will be described based on illustrated examples, but the present invention is not limited to these examples.

FIG. 1 is a side cross-sectional view showing an embodiment of the denture base forming apparatus of the present invention using an infrared heating method, in which a shows the state during heating and softening, and b shows the state during molding.

Reference numeral 1 denotes a thermostatic chamber, and the thermostatic chamber 1 houses a lower flask 3 on which a thermoplastic resin 2 is placed and an upper flask 4 containing an artificial tooth 18 therein. The lower flask 3 is heated by a lower infrared heater (hereinafter referred to as lower heater) 5, while the upper flask 4
is the upper infrared heater (hereinafter referred to as the upper heater).
6, and each is adjusted to a desired temperature.

In addition, here, the lower heater 5 and the upper heater 6 are as follows.
Inside the heater box 7, the lower heater 5 and the upper heater 6 are arranged back to back, and also serve as a partition plate 13 that divides the thermostatic chamber 1 into two. In addition, the upper flask 4 is attached to the press fixing plate 8,
The lower flasks 3 are each installed on a press moving plate 9, and the press moving plate 9 is raised and lowered by a cylinder 11 vertically installed on a press fixing plate 10.
Pressing (compression molding) of the thermoplastic resin 2 is performed.

Therefore, during heating and softening, as shown in FIG. It will accommodate flask 3. Thereafter, the upper flask 4 and lower flask 3 are heated by the upper heater 6 and the lower heater 5, respectively, so that the temperature is adjusted to a desired temperature, and the thermoplastic resin 2 is heated and softened.

Next, as shown in FIG. 1b, the heater box 7 is moved to the right in the figure by the cylinder 12, the press moving plate 9 is raised by the cylinder 11, and the upper flask 4 and lower flask 3 are brought together and the thermoplastic Resin 2 is compression molded.

FIG. 2 is a side cross-sectional view showing an embodiment of the denture base forming apparatus of the present invention using a hot air heating method, in which a shows the state during heating and softening, and b shows the state during molding.

As shown in FIG. 2a, during heating and softening, the thermostatic chamber 1 is divided by a partition plate 13 into a portion on the upper flask 4 side and a portion on the lower flask 3 side. The upper heater 14 is provided on the right side in the figure in the thermostatic chamber 1, and the upper flask 4 is adjusted to a desired temperature by a blower 15. Further, the lower heater 16 is located on the right side in the figure in the constant temperature room 1 and is located on the upper right side of the temperature-controlled room 1.
The thermoplastic resin 2 placed on the lower flask 3 is heated and softened by the blower 17 at a desired temperature.

Next, as shown in FIG. 2b, the partition plate 13 is removed, the press moving plate 9 is raised by the cylinder 11, the upper flask 4 and the lower flask 3 are brought together, and the thermoplastic resin 2 is compression molded.

Hereinafter, more specific implementation results regarding the device of the present invention will be explained.

(Example 1) After drying and heating the upper and lower plaster molds manufactured according to the standard dental method at 150°C for the upper mold and 200°C for the lower mold, the upper and lower flasks were molded into thermoplastic molds as shown in Figure 1. The resin polysulfone was set. The resin was heated to a resin surface temperature of 350° C., and after removing the heater, pressing was performed with a mold clamping force of 3 tons. At this time, the constant temperature room ambient temperature was 150° C., and the time required from the end of resin heating to the pressing step was 1 to 2 seconds.

As a result, a good maxillary complete denture with thin burrs and no molding defects was created.

(Example 2) Using the apparatus shown in Figure 2, the upper mold atmosphere temperature was
Except that the temperature was set at 150℃ and the lower mold atmosphere temperature was 380℃.
A denture base was compression molded in the same manner as in Example 1.

As a result, as in Example 1, a good maxillary complete denture was made.

(Comparative example) According to the device shown in Utility Model Application Publication No. 59-57919, the surface temperature of polysulfone was controlled in a constant temperature room for resin heating.
After raising the temperature to 350°C, the lower flask was taken out from the thermostatic chamber along the guide, and the upper flask, which had been set in advance at the top of the press, was pressed together to produce a maxillary complete denture.

In this case, it takes 8 seconds to take the lower flask out of the constant temperature room for resin heating, set it in the predetermined position of the press, confirm the position, and move on to the pressing process, and the surface temperature of the resin varies from 350°C to 350°C. 30 to 320℃
The temperature decreased.

As a result, the resin flow is poor and the burr is 0.2
It became thicker to ~0.3mm.

[Effects of the Invention] As explained above, according to the denture base molding apparatus according to the present invention, when molding a denture base made of thermoplastic resin, a denture base that is free from burning and has thin burrs and no defects can be obtained. In particular, it has the advantage of significantly improving denture bases made of thermoplastic resins with high melting points, such as polycarbonate and polysulfone.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view showing an embodiment of the denture base molding apparatus of the present invention using an infrared heating method, in which a shows the state when the device is softened by heating, and b shows a state when it is molded. FIG. 2 is a side cross-sectional view showing an embodiment of the denture base forming apparatus of the present invention using a hot air heating method, in which a shows the state during heating and softening, and b shows the state during molding. DESCRIPTION OF SYMBOLS 1... Constant temperature chamber, 2... Thermoplastic resin, 3... Lower flask, 4... Upper flask, 5... Lower heater, 6... Upper heater, 7... Heater box,
8... Press fixing plate, 9... Press moving plate, 10... Press fixing plate, 11... Cylinder,
12...Cylinder, 13...Partition plate, 14...Upper heater, 15...Blower, 16...Lower heater, 17...Blower, 18...Artificial tooth.

Claims (1)

[Claims] 1. In an apparatus for obtaining a denture base by placing a heat-softened thermoplastic resin between upper and lower split molds for denture base molding and compression molding this, Equipped with a means for heating a plastic resin and a means for pressing a thermoplastic resin softened by heating, the thermostatic chamber is divided into an upper chamber and a lower chamber by a partition plate inserted between the upper and lower molds. The denture base is characterized in that the upper chamber is equipped with a heater that heats the artificial tooth to a temperature that does not cause thermal deformation, and the lower chamber is equipped with a heater that heats the thermoplastic resin to a temperature that can soften it. Molding equipment. 2. The denture base forming device according to claim 1, wherein the heating means is a hot air heating means or an infrared heating means.