BRACES AND PLASTIC GUARDS OR ALIGNERS FOR USE IN THE TREATMENT OF MALFACIES, WHERE THE USE INCLUDES FORCE MEASUREMENT

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a computer-assisted intraoral recording device. BACKGROUND OF THE INVENTION

[0002] Aligner therapy (from "to align" = "to align") is an orthodontic treatment method for the largely invisible treatment of mild to severe malocclusions. It uses a sequence of individually manufactured, thin, and transparent plastic aligners. The plastic aligners are manufactured using deep-drawing processes from thermoformed foils or through additive manufacturing processes such as 3D printing.

[0003] For treatment to be successful, the aligners must exert a sufficiently high force on the tooth. Over time, the plastic material from which the aligners are made deforms. As a result, the force applied to the tooth is reduced, and effective treatment can no longer be guaranteed. Therefore, the doctor uses a new aligner at regular intervals to ensure successful continuation of treatment.

[0004] For the effectiveness of the therapy, it is important that the aligners are of consistent quality over the duration of use.

[0005] US2008248439A1 discloses an orthodontic device and method.

[0006] Reference is made to WO2006096558. DISCLOSURE OF THE INVENTION

[0007] Currently, the inventors are not aware of any state of the art technology that would allow the doctor / patient to easily determine the effectiveness of the treatment, monitor the progress of the treatment and, for example, determine the time to change to a new aligner.

[0008] The aim of the present invention is to provide a method for measuring the force of aligners in order to determine the effectiveness of the therapy and to monitor the progress of the therapy.

[0009] These objects have been achieved by the computer-assisted intraoral imaging device according to claim 1. The subject matters of the dependent claims relate to further developments and preferred embodiments.

[0010] An aligner is provided for use in the treatment of malocclusions, wherein the use comprises measuring the force of the aligner on the teeth. In the initial state, there are at least two reference features on the aligner. These reference features are large enough to be precisely recorded by a camera or other aid. The reference features are optical and / or topographical in nature. The reference features can be located on the inside and / or outside of the aligner. Optical features can be colored markings or differences in contrast. Topographical features can be elevations or depressions or regular structures on the surface. Optical and topographical features are approximately or at least 10 µm in size, or preferably 10 µm to 100 µm in size, or preferably 10 µm to 1000 µm in size. These can preferably comprise microlenses and / or microreflectors.

[0011] The method for measuring the force in aligners comprises the following steps: Providing the force / displacement curves of the plastic used in the aligner in the initial state; Determining the displacement of at least two reference features from each other relative to the initial state due to the force applied while wearing of the aligner from the patient, using a camera or other suitable tool, e.g., for optical measurement; calculation of the forces acting on the tooth by converting the determined displacement using the provided force / displacement curve.

[0012] According to the present invention, it is possible to determine the force applied to the tooth with aligners, or to determine whether the minimum necessary force is being applied to the tooth. The required forces per tooth can vary depending on biology and the desired displacement. However, the desired forces are always in the range between 0.05 N and 5 N.

[0013] The present invention also makes it possible to determine how the force acting on the teeth changes during the course of wearing the aligner, or to determine whether the force acting on the teeth falls below a necessary limit during the course of wearing the aligner. The force can be determined very locally.

[0014] When aligners are worn for a longer period of time, they lose their internal tension. This means that deformations and thus the displacement of the reference features are irreversible. Another embodiment focuses on detecting this type of irreversible deformation in order to determine the time to replace the aligner. Therefore, in another embodiment, the method comprises the following steps: determining the displacement of the at least two reference features from each other relative to the initial state caused by the force. after removal of the aligner using a camera or other device; and calculating the forces acting on the tooth by converting the determined displacement using the provided force / displacement curve.

[0015] According to the present invention, it is further possible for the doctor / patient to have the time of change displayed using a simple tool, e.g. a mobile phone camera & app or an intraoral camera such as Primescan & software. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the following description, the present invention is explained in more detail using exemplary embodiments with reference to the drawings. Figures 1-3 depict braces and aligners, which, however, are not part of the claimed invention. Fig.1 - shows a schematic representation of braces; Fig.2 - shows a schematic representation of an aligner from above; Fig.3 - shows a schematic representation of an aligner from the front.

[0017] The reference numbers shown in the drawings indicate the elements listed below, which will be referred to in the following description of the exemplary embodiments. 1. Braces 1a. Wire 1b. Reference feature 2. Aligner / Plastic splint 2a. Plastic 2b. Reference feature

[0018] The brace does not fall within the scope of the claimed invention and serves only as a comparative example to improve the understanding of the invention.

[0019] Fig.1shows, according to a comparative example, a brace (1) for use in the treatment of malocclusions by measuring the force on the brace. In the initial state, at least two reference features (1b) are located on the wire (1a) of the brace. These reference features (1b) are large enough to be accurately captured by a camera or other aid. The reference features (1b) are optical or topographical in nature. The number of reference features (1b) can also be more than two.

[0020] Fig.2 and Fig.3According to one embodiment, an aligner (2) for use in the treatment of malocclusions by means of force measurement on the same. In the initial state, at least two reference features (2b) are located on the plastic (2a) of the aligner (2). These reference features (2b) are so large that they can be precisely recorded by a camera or another aid. The reference features (2b) are of an optical or topographical nature. The number of reference features (1b) can also be more than two. Preferably, the marking of the reference features (1b; 2b) of the wire (1) or aligner (2) can be carried out with a laser. This allows markings to be applied to the wire (1a) and plastic (2a) precisely in the micrometer range.

[0021] The following procedure for force measurement in braces (1) or aligners (2) is explained in detail. Implementing the procedure requires the provision of a marked brace (1) or aligner (2), as well as the determination of the displacement and its evaluation.

[0022] Due to the force applied when wearing the braces (1) or the aligner (2), these reference features (1b; 2b) shift from one another. This shift can be converted into a force using the force / displacement curve of the material. This makes it possible to calculate the forces acting on the tooth. For this purpose, the force / displacement curves of the wire (1) used for the braces (1) or the plastic (2a) of the aligner (2) are predetermined. The force / displacement curve is a material-specific property. However, the thickness of the aligner (2) or the wire (1a) is used in the subsequent calculation of the force.

[0023] Furthermore, it is possible to measure the force applied to braces during the attachment of the wire and to correct it if necessary.

[0024] When aligners (2) are worn for a longer period of time, they lose their internal tension. This means that deformations and thus the displacement of the reference features (2b) are irreversible. This means that even after Remove of the aligner (2) to determine which forces have acted and whether the aligner (2) is still able to apply sufficient force to the teeth.

[0025] The measurement and evaluation of the data are preferably programmed as a software solution.

[0026] According to the present invention, the data sets generated by the above-mentioned methods can be presented to a physician for visualization, in particular for therapeutic diagnostic purposes, preferably by means of a screen or printout.

[0027] The method according to the invention is a computer-implemented method that is carried out on a computer-assisted intraoral recording device. For this purpose, the present invention also comprises a computer program with computer-readable code. The computer program can be provided on a data storage device. The computer-assisted intraoral recording device comprises a camera for providing the patient image. The computer-assisted intraoral recording device further comprises a computer or a computing unit that is connectable to the camera. The computer can be connected to the camera locally or alternatively via the Internet. The computing steps can take place locally or in the cloud. The computer or computing unit executes the computer program and provides the data sets, among other things for visualization on a display.The computer-assisted intraoral imaging device preferably further comprises a display for visualizing the data sets to a physician. The intraoral imaging device preferably comprises a mobile phone camera and app, or an intraoral camera such as the Primescan and software.

Claims

1. A computer-assisted intraoral recording device comprising a camera and a computing unit configured to execute a computer program, the computing unit comprising computer-readable code which, when executed by the computer-assisted intraoral recording device, causes the recording device to execute method steps of a method for measuring the force of an aligner (2), wherein the computer-assisted intraoral recording device is configured for use with an aligner in which there are at least two referencing features (1b;2b) located on the aligner (2) in the initial state, wherein these referencing features (1b;2b) are large enough, preferably approximately or at least 10 micrometers, for the camera to detect them precisely, wherein the referencing features (1b;2b) are visual or topographical features, wherein the method comprises the following steps: providing the force / path curves of the plastic (2a) used for the aligner (2) in the initial state; using the camera, ascertaining the displacement of the at least two referencing features (1b;2b) from one another relative to the initial state caused by the force exerted while the patient is wearing the aligner (2); calculating the forces acting on the tooth by converting the ascertained displacement using the force / path curve provided and the known geometry of the plastic (2a).

2. The computer-assisted intraoral recording device according to claim 1, characterized in that the method further comprises the following steps: using the recording from the camera, ascertaining the displacement of the at least two referencing features (2b), caused by the exerted force, from one another relative to the initial state after removal of the aligner (2); calculating the forces acting on the tooth by converting the ascertained displacement using the force / path curve provided and the known geometry of the aligner (2).

3. The computer-assisted intraoral recording device according to claim 1 or 2, characterized in that it comprises a mobile phone and an app corresponding to the computer program.