HK1098659A - Device and method for vacuum assisted dental impression - Google Patents

Description

Device and method for vacuum assisted dental impression manufacture

This application claims priority from U.S. provisional patent application No. 60/532,505, filed 24/12/2003, the disclosure of which is incorporated herein by reference.

Technical Field

The present invention relates to an apparatus and method for making a dental model, and more particularly, to an apparatus and method for drawing a material for making an impression into contact with a patient's teeth in a dental impression tray using a suction device. The invention is particularly useful for making dental models of a patient's teeth by selectively providing suction to draw impression making material into selected locations in the mouth into contact with the patient's teeth, although the invention is not limited in its application.

Background

Dentists typically require dental molds to make artificial teeth, crowns, or other dental prostheses. Dental molds are currently generally made using impressions left in a dental impression tray filled with a self-hardening gel-like compound. In making an impression, the tray is placed in the patient's mouth and the compound fills the area around the teeth before hardening, the tray and compound are then removed from the patient's mouth, the material from which the impression is made is poured into the dental impression, and the material hardens to form a model of the patient's teeth.

Before preparing the dental crown, the tooth is generally required to be shaped and reduced in volume, so that the dental crown can be inserted into the tooth without affecting other teeth of a patient. After a tooth is shaped, a gingival retraction cord is typically placed around the tooth prior to taking a dental impression. The impression taken is used to make the dental model required by the dentist in making the crown.

Clearly, the crown must be able to precisely match the position of the shaped tooth and the adjacent teeth. Furthermore, the crown of the tooth must not impede the patient's chewing. Thus, the dental impression must be accurate in order to make a suitable crown. However, dental impressions made with the prior art often exhibit serious errors. The movement of the patient's tongue, lips, cheeks or jaw is one of the causes of error. Other reasons include the inability of the impression material to fit snugly against the teeth because the material is designed to move easily away from the teeth. As a result, dental molds made with these inaccurate impressions are also inaccurate. More importantly, crowns or other dental prostheses manufactured using these inaccurate dental molds are also inaccurate. In order to solve this problem, a dentist often needs to modify the crown of a tooth when the dentist puts the crown on the shaped tooth, which brings great inconvenience to the dentist and the patient.

In view of the above problems, it is an object of the present invention to provide an apparatus and method for making an impression of a more accurate dental mold. It is another object of the present invention to provide an apparatus and method for producing an impression of a dental mold by applying suction to the impression material to the teeth. It is another object of the present invention to provide an apparatus and method for making a dental impression that an impression of a patient's teeth is taken prior to taking a final impression of a shaped tooth. It is another object of the present invention to provide an apparatus and method that can selectively aspirate impression material within a patient's mouth to make a dental impression. It is also an object of the present invention to provide a device for making a dental impression and a method of using the device that is relatively simple to manufacture, easy to operate and cost effective.

Disclosure of Invention

The present invention relates to a dental impression device for making a dental prosthesis, preferably comprising a dental tray for cooperation with a vacuum source, and an obstruction for cooperation with the tray for obstructing suction from the vacuum source at selected locations of the tray.

Structurally, the dental tray includes a generally U-shaped base extending from a labial (or buccal) position to a lingual position. The lip-side position of the bottom is connected with a substantially U-shaped lip-side wall extending outward from the bottom. The tongue side of the base is connected to a generally U-shaped tongue wall extending outwardly from the base. In making an impression of maxillary teeth, the tray may further comprise a jaw member connected to an upper edge of the lingual wall and spanning the gap created by the U-shaped lingual wall. The bottom, the lip wall and the tongue wall preferably constitute the outer surface of the dental tray and also constitute the inner surface of the dental tray provided with a groove.

In the invention, the bottom of the groove is provided with a groove, and the groove comprises a series of openings. The opening is in fluid communication with a conduit that extends from the recess to a delivery port located on the outer surface of the tray. Specifically, the delivery tube is connected to the conduit at the outer surface to communicate with the vacuum source. In addition, a stopper is disposed within the recess that selectively engages the opening and interferes with (i.e., blocks) fluid communication of the opening with the vacuum source. If desired, the obstruction may be divided into multiple obstruction segments to engage selected non-adjacent openings. The blocking section may also preferably include a projection extending outwardly from the recess.

When the dental false tooth mold is manufactured, the blocking object is placed in the groove to block the opening, and the impression material is placed in the groove of the tray. The tray is then placed over the patient's teeth so that the impression material surrounds the teeth. The impression material is shaped to form a semi-impression of the tooth. After removal of the tray, a dental work is performed on the selected tooth. The dental work preferably comprises removing dental substance from the tooth.

After the dental work is completed, the final impression of the tooth is taken. Prior to making the stamp, selected blocking sections of the tray recesses are removed so as not to block selected openings. The half impression is cut to remove the blocking section, and in addition to this, if the projection of the blocking section protrudes through the half impression, the blocking section can be pulled away from the recess simply by grasping the projection. Regardless of which method is used, one or more openings may appear in the half-impression after removal of the selected occlusion. Subsequently, another impression material is added to the semi-impression, the viscosity of the impression material preferably being lower than the viscosity of the impression material of the previous run. Preferably at least a portion of the impression material is disposed on an upper edge of the labial and lingual walls of the impression. When the tray and the half-impression are replaced in the patient's mouth, the impression material is drawn into the shaped teeth by contacting the patient's teeth.

To further draw the impression material to the shaped teeth, the vacuum source is in fluid communication with the unobstructed opening. In particular connecting the conduit to the vacuum source to achieve this effect. After connection, the vacuum source is activated and the impression material is drawn into the openings of the semi-impression to contact the shaped teeth and shape the impression thereof. After the impression material is set, the dental tray and final impression are removed from the oral cavity. The final impression can be used to make a crown or other dental prosthesis.

The recess is located at the bottom of the dental tray, but may be located elsewhere, such as the labial wall. In addition, multiple grooves and obstructions may be utilized to increase the vacuum suction at selected locations in the mouth. For example, a groove in fluid communication with one or more vacuum sources is added to the base and the lip wall.

In addition, the viscosity of the above-mentioned impression material for making the final stamp is lower than that of the impression material for making the half stamp, but an impression material having the same viscosity or higher may be used as desired.

Finally, the above only discusses making a crown for a tooth, but the present invention can assist in making any dental prosthesis that requires an impression.

Drawings

The invention, together with the novel features and structure, further evident from the detailed description given below with reference to the accompanying drawings, and the accompanying parts including the character references:

figure 1 is a perspective view of a patient receiving a dental impression apparatus of the present invention.

Fig. 2 is a perspective view of the dental impression device of the present invention shown in fig. 1 fitted over a patient's teeth, showing a conceptual view of the hidden structure for clarity.

Fig. 3A is a cross-sectional view taken along line 3-3 of fig. 2, showing the tooth and impression material in a first molding process with the channel having only one groove.

FIG. 3B is a cross-sectional view similar to FIG. 3A, showing the tooth and impression material in a first molding operation with two grooves in the channel.

Figure 3C shows a cross-sectional view of the tooth of figure 3A after it has been reshaped and replaced in a dental tray.

FIG. 3D shows a cross-sectional view of the tooth of FIG. 3C after a blocking section has been removed from the semi-impression and impression material has been pumped into the shaped tooth.

Fig. 3E is a cross-sectional view of the tooth of fig. 3A showing another obstruction having a projection that contacts the tooth.

Fig. 3F is a cross-sectional view of the tooth of fig. 3E after removal of the selected occlusion and reshaping and repositioning of the tooth in the dental tray.

Fig. 3G is a cross-sectional view of the tooth of fig. 3F after the impression material has been drawn into the shaped tooth.

Figure 4A is an exploded perspective view showing the components of the dental impression device of figure 2.

Figure 4B is an exploded perspective view showing components of another dental impression device similar to that shown in figure 4A.

Detailed Description

Figures 1 and 2 show a dental impression device 10 of the present invention.

As shown in FIG. 1, a dental impression device 10 is fitted over a tooth 14 of a patient 12. The dental impression apparatus 10 includes a dental tray 16. The dental tray 16 has an impression material 18 disposed therein, the impression material 18 contacting the patient's teeth 14 to form an impression of the teeth 14. Fig. 1 also shows a delivery tube 20 extending from an outer surface 22 of the dental tray 16.

Fig. 4A and 4B show other configurations of the dental impression device 10. In addition to the outer surface 22, the dental tray 16 also includes an inner surface 24. As shown, portions of the outer surface 22 and the inner surface 24 are formed by a U-shaped base 26, the U-shaped base 26 extending from a labial position 28 to a lingual position 30. A U-shaped lip wall 32 extends upwardly from the lip side location 28 of the base 26. Similarly, a U-shaped lingual wall 34 extends upwardly from the lingual position 30 of the base 26. Fig. 4B shows the lingual wall 34 terminating in the margin 36 when the dental impression apparatus 10 is applied to a mandibular tooth. Figure 4A shows the dental impression device 10 applied to maxillary teeth with a jaw member 38 attached to the lingual wall 34 across the gap 40 created by the lingual wall 34.

As shown in Figs. 4A and 4B, the interior surface 22 of the dental tray 16 has a channel 42 for receiving the patient's teeth 14 and the impression material 18. The channel 42 includes a recess 44 formed by an upstanding member 46 preferably integrally formed with the U-shaped base 26. At the bottom of the groove 44 is a conduit 48 connecting the groove 44 to the delivery port 20. A seat 50 is disposed within the recess 44, the seat 50 having an opening 52 in fluid communication with the conduit 48. In addition to the dental tray 16, fig. 4A and 4B also show a blockage 54. A stopper 54 may be positioned within groove 44 to block opening 52. The obstruction 54 may be comprised of a plurality of obstruction segments 56 that maintain the other openings 52 unobstructed while partially obstructing the openings 52.

Fig. 3A illustrates a method of implementing the dental impression apparatus 10, taking as an example a tooth 58 to be subjected to a dental work. As shown, the channels 42 in the dental tray 16 receive the teeth 58 and also receive the impression material 18 that surrounds the teeth 58. The impression material 18 is initially a viscous liquid that thereafter hardens into a solid dental impression 60 to capture a negative of the tooth 58. As shown, the impression material 18 surrounds the entire tooth 58 and contacts the patient's gums 62.

Fig. 3A also clearly shows the components of the dental impression device 10. For example, stopper 54 is shown blocking opening 52 in housing 50. Below the opening 52 is a conduit 48 to which the delivery port 20 is connected.

Fig. 3B shows another embodiment of a dental tray 16. In this example, the channel 42 in the dental tray 16 includes a bottom recess 44a and a wall recess 44 b. As shown, grooves 44a and 44b are blocked by blockages 54a and 54b, respectively. Also, the components of grooves 44a and 44b are substantially identical and each include a conduit 48 that connects to delivery port 20.

Fig. 3C shows the tooth 58 undergoing dental work including shaping. As shown, a space 64 is present between the tooth 58 and the impression 60. The space 64 is equivalent to the volume of dental substance removed from the tooth 58. As shown in fig. 3C, the blocking section 56 of the obstruction 54 has been removed from the dental tray 16. Specifically, when the dental impression 60 pierces the opening 68, the blocking section 56 is pulled out of the recess 44 through the opening 68.

Fig. 3D shows that suction generated by vacuum source 70 (shown in fig. 2) draws impression material 72 through conduit 48 into space 64. As shown, the impression material 72 contacts the teeth 58 and the impression 60 and fills the space 64. The impression material 72 hardens into a dental mold 74 for making a dental prosthesis such as a crown.

Fig. 3E-3G illustrate another embodiment of stopper 54 including a projection 76. As shown in fig. 3E, the projections 76 extend out of the impression material 18 to contact the teeth 58 during formation of the impression 60. After removing the dental tray 16 and impression 60 from the patient's mouth 15, the selected blocking section 56 can be pulled away from the recess 44 by grasping the selected projections 76.

As shown in fig. 3F, the original position of the projection 76 leaves an opening 68 after removal of the selected blocking section 56. A vacuum source 70 draws the impression material 72 into the space 64 around the teeth 58 using the apertures 68. As shown in FIG. 3F, the impression material 72 is disposed on an end portion 78 of the labial wall 32 and an end portion 79 of the lingual wall 34 of the dental tray 16, and the impression material 72 is also disposed on an end portion 80 of the impression 60 adjacent to the labial wall 32 and an end portion 81 of the impression 60 adjacent to the lingual wall 34 of the dental tray 16. When the tray 16 is placed over the patient's teeth 14, the impression material 72 is drawn into the space 64.

After the tray 16 is placed over the patient's teeth 14, the vacuum source 70 is connected and activated to draw the impression material 72 onto the shaped teeth 58 to form a dental model 74. Fig. 3G shows the tooth die 74 after this process is completed. As shown, the impression material 72 is drawn completely into the space 64, through the aperture 68 and the opening 52 and into the conduit 48.

The above embodiments of the apparatus and method are sufficient to achieve the above objects and provide the above advantages, but the above embodiments are only preferred embodiments of the present invention, and the present invention is not limited by the scope of the claims.

Claims (20)

1. A dental impression apparatus for making a dental prosthesis, characterized by: the dental impression apparatus comprises a dental tray including an outer surface, an inner surface having a channel for receiving a patient's teeth and impression material, an opening in the channel, and a conduit extending from the opening to a delivery port for connection to a vacuum source for drawing the impression material in the channel to the opening; the dental impression apparatus further includes a stopper that engages the selected opening to limit suction to selected portions of the trough when the impression material is drawn into contact with the patient's teeth.

2. Dental impression device according to claim 1, characterized in that: the dental impression apparatus further comprises a recess disposed in the channel, the opening is disposed in the recess, and the blocking object is disposed in the recess to engage a selected one of the openings.

3. Dental impression device according to claim 1, characterized in that: the obstruction includes a plurality of obstruction segments to engage non-adjacent selected ones of the openings.

4. Dental impression device according to claim 1, characterized in that: the dental tray comprises a bottom which extends to a position close to the lip side from the position close to the tongue side and is approximately U-shaped, a tongue wall which is connected with the bottom and is approximately U-shaped close to the position close to the tongue side, and a lip wall which is connected with the bottom and is approximately U-shaped close to the position close to the lip side, wherein the bottom, the tongue wall and the lip wall form the inner surface and the outer surface.

5. Dental impression device according to claim 4, characterized in that: the lingual wall extends to an edge to form a void, and the dental impression apparatus further includes a jaw member coupled to the lingual wall edge and spanning the void.

6. Dental impression device according to claim 4, characterized in that: the dental impression apparatus further includes a recess in the bottom or the labial wall, the opening being disposed in the recess, and the obstruction being disposed in the recess to engage a selected one of the openings.

7. Dental impression device according to claim 4, characterized in that: the dental impression device further comprises a bottom groove in the bottom and a lip wall groove in the lip wall, the opening is arranged in the bottom groove and the lip wall groove, the blocking object comprises a plurality of blocking object sections arranged in the bottom groove and the lip wall groove to be jointed and selected.

8. A dental impression apparatus for making a dental prosthesis, characterized by: the dental impression apparatus includes a dental tray including an outer surface, an inner surface having channels for receiving the patient's teeth and impression material, a suction device for drawing the impression material into contact with the patient's teeth, and a means for focusing the suction device on a selected tooth to draw the impression material into contact with the selected tooth.

9. Dental impression device according to claim 8, characterized in that: the means for concentrating the suction device includes an obstruction that blocks the suction device from drawing the impression material into contact with non-selected teeth.

10. Dental impression device according to claim 9, characterized in that: the obstruction includes a plurality of obstruction segments that obstruct the suction device from drawing the impression material into contact with non-adjacent non-selected teeth.

11. Dental impression device according to claim 8, characterized in that: the suction device comprises a plurality of openings arranged in the groove and a pipeline extending from the openings to a delivery port to be connected with a vacuum source.

12. A method of forming a dental prosthesis in a dental tray, the method comprising the steps of:

placing a first impression material into the dental tray;

forming a dental impression from the first impression material by fitting the dental tray over a patient's teeth;

removing the dental tray from the patient's teeth;

performing a dental work on at least one selected tooth, including removing a selected amount of a dental substance from the selected tooth;

placing a second impression material into the dental impression;

re-fitting said dental tray and said dental impression with said second impression material over the patient's teeth, said dental impression forming a space with the selected teeth;

and (4) making vacuum in the space, and sucking the second impression material into the space to contact with the selected teeth so that the second impression material forms the dental artificial tooth model.

13. The method of claim 12, wherein: the dental tray includes a channel having a plurality of openings for receiving the impression material and a conduit extending from the openings to a delivery port for connection to a vacuum source for drawing the second impression material into the space.

14. The method of claim 13, wherein: the method further includes blocking the opening in the channel with a stopper during formation of the dental impression, and removing the stopper of at least one selected opening prior to the step of forming the impression, leaving the vacuum source to draw the second impression material into the space.

15. The method of claim 14, wherein: the method further includes piercing at least one opening in the dental impression to remove a blockage of at least one selected opening and allowing the vacuum source to draw the second impression material through the opening to the space.

16. The method of claim 14, wherein: the stopper contacts a selected tooth prior to the dental impression formation process and the dental work step to form at least one opening in the dental impression, the opening being in fluid communication with the vacuum source after the stopper is removed from the dental tray, the vacuum source being caused to draw the second impression material through the opening to the space.

17. The method of claim 13, wherein: the groove comprises a groove, the opening is arranged in the groove, and the method further comprises the following steps:

placing a stopper in the recess to block the opening before placing the first impression material in the dental tray; and

removing the blockage of at least one selected opening before the vacuum source draws the second impression material into the space.

18. The method of claim 17, wherein: the step of removing the obstruction includes moving the obstruction section of the obstruction away from the recess through the dental impression to remove the obstruction of the selected opening.

19. The method of claim 12, wherein: the first impression material and the second impression material contain different substances.

20. The method of claim 19, wherein: the second impression material has a lower viscosity than the first impression material.