US-12623396-B2 - Hand tool for separating a deep-drawn jaw-spanning dental apparatus of thermoform film

Abstract

A hand tool ( 1 ) for separating a deep-drawn jaw-spanning dental apparatus such as an aligner or a bite splint of thermoform film. The hand tool includes a grip ( 2 ) for holding; a separating element ( 3 ) for thermally separating the deep-drawn thermoform film and refining the separated deep-drawn thermoform; a heating device adapted to regulate heating of the separating element ( 3 ) so as to increase the temperature of the thermoform film substantially to at least its glass temperature; and a power supply device for supplying electric power to the heating device.

Inventors

• Hans-Christian SCHNEIDER
• Peter Burger

Assignees

• DENTSPLY SIRONA INC.

Dates

Publication Date

20260512

Application Date

20210311

Priority Date

20200320

Claims (17)

1. 1 . A hand tool for separating a deep-drawn jaw-spanning dental apparatus comprising: a grip; a separating element configured to thermally separate a deep-drawn thermoform film and refine the separated deep-drawn thermoform in a single step; a heating means configured to regulate heating of the separating element so as to increase the temperature of the thermoform film substantially to at least its glass temperature without degradation and unnecessary melting of the thermoform film; and a power supply means for supplying electric power to the heating means; wherein the separating element is configured to follow a separation contour on the thermoform film.
2. 2 . The hand tool according to claim 1 , further comprising: a temperature sensor configured to sense the temperature of the thermoform film in close proximity to the separating element, wherein the heating means is further configured to regulate heating of the separating element based on the sensed temperature.
3. 3 . The hand tool according to claim 1 , wherein the heating means is further adapted to regulate heating of the separating element so as to increase the temperature of the thermoform substantially to at least 105 degrees Celsius which corresponds to the glass temperature of Polymethylmethacrylate.
4. 4 . The hand tool according to claim 1 , wherein the separating element is provided in the form of a knife, chisel, a spike, or a needle which protrudes from the front of the grip.
5. 5 . The hand tool according to claim 1 , further comprising a suction means which comprises: a channel which is arranged in close proximity of the separating element; a filter arranged in the channel; and a fan adapted to extract the fumes resulting during the separation of the deep-drawn thermoform film into the channel towards the filter, wherein the suction means is integrated into the grip, and the power supply means is further adapted to supply electric power to the fan.
6. 6 . The hand tool according to claim 1 , further comprising a suction means which comprises: a channel which is arranged in close proximity of the separating element; and a hose connected to the channel for conveying the fumes resulting during the separation of the deep-drawn thermoform film to an external extractor which is detachably connectable or connected to the hose.
7. 7 . The hand tool according to claim 6 , wherein the hose is detachably connectable to the channel at the rear of the grip.
8. 8 . The hand tool according to claim 1 , further comprising an illuminating means, wherein the power supply means is further adapted to supply electric power to the illuminating means.
9. 9 . The hand tool according to claim 8 , wherein the illuminating means has a laser pointer which is arranged in close proximity to the separating element and adapted to provide visual guidance for the user when moving the separating element.
10. 10 . The hand tool according to claim 8 wherein the illuminating means has one or more light sources adapted to illuminate at least the tip of the separating element.
11. 11 . The hand tool according to claim 8 , wherein the illuminating means has one or more light sources with one or more different colors, wherein the illuminating means is adapted to indicate the temperature of the separating element through selecting a corresponding color.
12. 12 . The hand tool according to claim 1 , wherein the power supply means is operable by one or more rechargeable batteries, wherein the grip has a battery holder for receiving one or more rechargeable batteries.
13. 13 . The hand tool according to claim 12 , wherein the power supply means has a charging unit connectable to the mains for recharging the batteries.
14. 14 . The hand tool according to claim 1 , wherein the power supply means is connectable to the mains via an electric cable.
15. 15 . The hand tool according to claim 14 , wherein the power supply means has a socket on the grip, wherein the socket can receive a plug of an electric cable which is connectable to the mains.
16. 16 . A method for separating a deep-drawn jaw-spanning dental apparatus comprising: thermally separating a deep-drawn thermoform film and refining the separated deep-drawn thermoform in a single step using a separating element of a hand tool, the hand tool comprising a grip; regulating heating of the separating element, using a heating means of the hand tool, to increase a temperature of the thermoform film substantially to at least its glass temperature without degradation and unnecessary melting of the thermoform film; and supplying, by a power supply means of the hand tool, electric power to the heating means; wherein the separating element is configured to follow a separation contour on the thermoform film.
17. 17 . The method of claim 16 , wherein the deep drawn thermoform file is obtained by deep drawing a thermoform film using a model to manufacture a jaw-spanning dental, and wherein the deep-drawn thermoform film is separated and refined while being supported or clamped by the model and the heated separating element is moved along a separation contour on the thermoform film or the model.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This is a National Phase application of International Application No. PCT/EP2021/056135, filed Mar. 11, 2021, which claims the benefit of and priority to European Application Ser. No. 20166847.2, filed on Mar. 30, 2020, which are herein incorporated by reference for all purposes. TECHNICAL FIELD OF THE INVENTION The present invention relates to a hand tool for separating a deep-drawn jaw-spanning dental apparatus such as an aligner or a bite splint of thermoform film. The present invention also relates to a method of using the hand tool. BACKGROUND OF THE INVENTION Jaw-spanning dental apparatuses made of polymethylmethacrylate or similar materials, such as aligners or bite splints for the treatment of bruxism, are exposed to considerable masticatory loads during their use. For this reason, they are still manufactured using the deep-drawing process of thermoform films, despite modern production methods such as 3D printing. A relatively complicated post-process after deep-drawing of the thermoform film is the manual cutting and trimming of the deep-drawn thermoform film by means of milling, grinding and/or polishing tools. The manual cutting and trimming of the deep-drawn thermoform film is done, for example, with rotating instruments operated by a motorized handpiece. The resulting sharp edges must be smoothed in a time-consuming process. SUMMARY OF THE INVENTION An objective of the present invention is to overcome the problems of the prior art and to provide a hand tool for separating a deep-drawn jaw-spanning dental apparatus such as an aligner or a bite splint of thermoform film. This objective has been achieved through the hand tool as defined in claim 1. The subject-matters of the dependent claims relate to further embodiments and developments. The present invention provides a hand tool for separating a deep-drawn jaw-spanning dental apparatus such as an aligner or a bite splint of thermoform film. The hand tool comprises: a grip for holding; a separating element for thermally separating the deep-drawn thermoform film and refining the separated deep-drawn thermoform; a heating means adapted to regulate heating of the separating element so as to increase the temperature of the thermoform film substantially to at least its glass temperature; and a power supply means for supplying electric power to the heating means. A major advantageous effect of the present invention is that by heating up the thermoform film substantially to at least its glass temperature, separation and refinement can take place in a single step. Thereby, the number of working steps can be reduced, a fast and smooth separation process can be achieved, and the overall process can be simplified. Another major advantageous effect of the present invention is that through the regulation of the temperature of the thermoform film substantially to its glass temperature, the separation of the thermoform film is possible without degradation and unnecessary melting thereof, and thus the risk of damaging the aligner or the bite splint can be prevented or reduced as much as possible. According to the present invention, the temperature regulation may be performed through closed loop or open loop. According to the present invention, the heating means regulates heating of the separating element so that the temperature of the thermoform film never reaches the degradation temperature of the thermoform film and remains well below the degradation temperature of the thermoform film, preferably substantially at the glass temperature of the thermoform film or slightly above. Therefore, in an embodiment, a temperature sensor is used for sensing the temperature of the thermoform film in close proximity to the separating element. The heating means regulates heating of the separating element based on the sensed temperature. Alternatively, a thermodynamic model may be applied to the heating means to obviate the need of using the temperature sensor. Thus, the heating means may regulate heating of the separating element based on the thermodynamic model which takes account of the temperature drop between the separating element and the thermoform film in close proximity thereof. The thermodynamic model may be based on empirical data. The deep-drawn jaw-spanning dental apparatus such as the aligner or the bite splint is usually made of Polymethylmethacrylate (PMMA). Therefore, in an embodiment, the heating means is further adapted to regulate heating of the separating element so as to increase the temperature of the thermoform substantially to at least 105 degrees Celsius which corresponds to the glass temperature of Polymethylmethacrylate. However, different type of thermoform films may be alternatively used. Therefore, alternatively, the user may be allowed to selectively set the heating means in accordance with the type of the thermoform film to be separated. According to the present invention, the separating element may be pr