Oral appliance

Abstract

The proposed aspects, solutions, concepts, designs, methods, and systems relate to assisting in evaluating the degree of fit of an oral appliance to a subject (i.e., a user). Embodiments propose to assess the degree of fit based on a mechanical response of the oral appliance to a mechanical stimulus applied to the oral appliance. In this manner, an indication or metric of the degree of fit of the oral appliance to the subject may be obtained.

Description

Technical Field

[0001] The present invention relates to the field of oral appliances and, in particular, to assessing the fit of an oral appliance worn by a subject. Background Art

[0002] It is known to provide oral appliances, such as mouth guards, dental braces, orthodontic care devices, etc., for placement in the mouth of a subject (i.e., user) during use. Such appliances typically require a good fit with the subject's teeth and / or gums (e.g., close alignment or matching geometries).

[0003] It is also known that many users do not wear or use oral appliances as instructed. Nevertheless, the timing of changing from a first orthodontic device to a different second device is typically based on a fixed schedule provided by a dental practitioner using remote planning or remote image analysis. Thus, the process relies on the subjective assessment of the dental practitioner or is completely independent of the actual wearing / use by the user. Therefore, there is a need for a systematic (i.e., objective) way to assess the fit of an oral appliance worn by a subject.

[0004] In addition, the fit of an oral appliance with a subject can change over time, e.g., due to deformation of the appliance and / or change in the position(s) of the subject's teeth. In fact, an oral appliance such as a dental brace can be specifically designed and used to change the position of a patient's teeth. Thus, wearing a dental brace will cause a change in the position of the subject's teeth, thereby changing the fit of the dental brace with the subject's teeth over time.

[0005] US2022 / 287636A1 describes a storage case for an instrumented intraoral appliance that contains recorded data, charges the intraoral appliance when not in use, and transfers the recorded data to a storage device for viewing and analysis. Summary of the Invention

[0006] The present invention is defined by the claims.

[0007] According to an example of one aspect of the present invention, there is provided a system for assessing the fit of an oral appliance worn by a subject, the system comprising:

[0008] a sensor unit configured to measure a mechanical response of the oral appliance to a mechanical stimulus applied to the oral appliance; and

[0009] a processor device configured to analyze the measured mechanical response to determine a fitness value that describes the fit of the oral appliance with the subject.

[0010] Accordingly, the proposed concept aims to provide solutions, concepts, designs, methods, and systems related to assisting in evaluating the fit of an oral appliance to a subject (i.e., the user). Embodiments of the present invention propose to evaluate the fit based on the mechanical response of the oral appliance to mechanical stimuli applied to the oral appliance. For example, by analyzing the frequency response of the oral appliance after impinging it with a pulsed force, it can be determined whether the oral appliance fits tightly / closely to the user's teeth and / or gums or fits loosely. In this way, an indication or measure of the fit of the oral appliance to the subject can be obtained.

[0011] Accordingly, embodiments can address the problem of evaluating the fit of an oral appliance (e.g., a dental aligner, an orthodontic device, etc.) by employing measurements of the mechanical vibration response to mechanical stimuli applied to the appliance. This provides objective feedback regarding the fit, which can then be used to provide guidance such as when to replace the oral appliance. The provision of such objective fit evaluations can also contribute to improving or optimizing dental treatment, such as by enabling treatment / wear schedules to be monitored for compliance and / or dynamically adapting to the user's actual wear / use.

[0012] It has been proposed that the force between the oral appliance and the wearer's teeth can serve as a measure of fit (e.g., greater force = closer fit). This force will affect the mechanical response of the oral appliance to mechanical stimuli applied to the oral appliance. By measuring the mechanical response to the stimuli, the fit can be evaluated. Additionally, by tracking / monitoring the change in the mechanical response over time, the change in the fit of the oral appliance can be evaluated. The device for measuring the mechanical response and / or the device for generating the stimuli can be provided within / on the oral appliance itself or can be provided external to the oral appliance, such as by an electric toothbrush (e.g., using the back of the toothbrush press plate).

[0013] It has been proposed that an oral appliance will exhibit a certain response to an applied mechanical stimulus, and this response can vary depending on the degree of its contact or pressure against the wearer's teeth and / or gums. In general form, this response is either expressed in the frequency domain, i.e., the frequency response, or in the time domain, i.e., the impulse response. Both can have several characteristics, such as:

[0014] - For the frequency response: (one or more) resonant frequencies, the quality factor of the resonant peak; and

[0015] - For the impulse response: maximum amplitude, decay time.

[0016] The principle of the proposed invention is that the static force (e.g., preload) between the oral appliance (e.g., an aligner) and the wearer's teeth / gums affects the mechanical response of the oral appliance to the stimulus. In particular, it has been observed that this occurs through non-linearity in the system, such as:

[0017] - For a vibrating toothbrush, the effective moving mass and / or the movement resistance and / or the (gingival) compliance depend on the static tooth displacement and are not constant. In turn, the static tooth displacement depends on the appliance tooth preload;

[0018] - During the entire vibration cycle, the contact between the oral appliance and the teeth depends on the preload. In particular, the possibility of an instantaneous loss of contact (i.e., detachment) between the oral appliance and the teeth significantly affects the vibration response of the oral appliance. For this case, the simulation results are shown below.

[0019] Based on the above realization(s), it is proposed to determine a change in the fitness of an oral appliance for a wearer by measuring a change in the response of the oral appliance to a stimulus (such as a vibration force).

[0020] Accordingly, embodiments can provide the advantage that the fitness of an oral appliance for a subject can be objectively evaluated and thus determined in an accurate and / or consistent manner. For example, embodiments can enable the fitness of a dental orthosis for a wearer to be accurately evaluated. In addition, such evaluations can be repeated at regular intervals over an extended period of time (e.g., daily over the course of one or more months) to monitor the fitness in a consistent manner and thus infer the degree of movement of the teeth of the wearer caused by the dental orthosis (e.g., from the detected changes in the fitness of the orthosis).

[0021] In other words, embodiments propose to determine the fitness of an oral appliance worn by a subject. The determined fitness can assist in oral care / treatment decisions. Accordingly, embodiments can be used for oral care / treatment selection to provide support to a user when selecting an oral care / treatment regimen.

[0022] For example, embodiments can provide a means for remotely evaluating the fitness of a dental orthosis in an objective and unobtrusive manner by being seamlessly integrated into the orthosis wearing workflow (e.g., without requiring the user / wearer to take an image). Such embodiments can also provide objective advice on replacing the orthosis (or wearing the orthosis for a longer period of time), thereby facilitating dynamic adjustment of the treatment (which can increase the success rate of the treatment and improve consumer satisfaction).

[0023] Accordingly, it should be understood that the proposed concept(s) can alternatively be used in various oral hygiene products / appliances that are positioned against the teeth and / or gums of a subject during use.

[0024] The sensor unit may include a motion sensor configured to measure at least one of an amplitude and a frequency of at least a part of the dental appliance. By way of example, the motion sensor may include at least one of the following: a gyroscope; an accelerometer; a magnetometer; and an inertial measurement unit (IMU). Thus, embodiments may utilize one or more widely available sensors, enabling a simple and cost-effective implementation of the proposed concept(s).

[0025] In some embodiments, the sensor unit may include at least one of the following: an accelerometer; a gyroscope; an inertial measurement unit IMU; and a piezoelectric transducer circuit configured to convert a parameter change of at least a part of the oral appliance into an electrical signal. The processor device may then be configured to convert the electrical signal into a fitness value. Thus, an accurate measurement of the mechanical response of the oral appliance can be achieved with a small and cost-effective device. This may also support integration into the oral appliance and provide signals that can be easily communicated and processed.

[0026] In one embodiment, the oral appliance may include a sensor unit. The oral appliance may then be located remotely from the processor device, and the system may further include a communication unit configured to transmit the measured mechanical response to the processor device. That is, embodiments may facilitate providing the sensor unit in or on the oral appliance when enabling the processor device to be separated from the oral appliance (e.g., in a smartphone, a tablet, or in the cloud).

[0027] In one embodiment, the sensor unit may also be configured to detect the application of a mechanical stimulus to the oral appliance. In response to detecting the application of a mechanical stimulus to the oral appliance, the sensor unit may be configured to measure the mechanical response of the oral appliance to the detected mechanical stimulus. In this way, the process of measuring and analyzing the mechanical response of the oral appliance can be restricted to relevant / appropriate times, thereby reducing power consumption and / or avoiding determining incorrect / irrelevant fitness values.

[0028] Some embodiments may further include: an output interface configured to output an instruction for prompting a subject to provide a mechanical stimulus to the oral appliance. The instruction may include, for example, guidance indicating that the subject perform a predetermined jaw movement or posture. For example, by instructing / guiding the subject, such embodiments may help ensure that the measurement of the mechanical response is consistent and accurate. For instance, the indicated posture may require the subject to open his / her mouth wide, reducing the contact of the oral appliance with the user's cheeks and / or tongue.

[0029] The system may also include a stimulation unit configured to generate mechanical stimulation and apply it to the oral appliance. Thus, embodiments may incorporate means for generating mechanical stimulation and applying it to the oral appliance. This may obviate the need to use a separate device and / or ensure that mechanical stimulation is applied in an accurate, consistent, and controlled manner.

[0030] For example, the stimulation unit may include at least one of the following: a piezoelectric transducer adapted to apply a force to at least a portion of the oral appliance; a vibration device adapted to vibrate at least a portion of the oral appliance; and a pulse device adapted to apply a pulsed force to at least a portion of the oral appliance. Thus, embodiments may employ relatively simple and / or widely available configurations, thereby enabling cost-effective implementation of the proposed concept(s).

[0031] In one embodiment, the processor device may be configured to: compare the measured mechanical response with a predetermined threshold; and determine a fitness value based on the comparison result. This may enable a relatively simple determination of the fitness value, thereby reducing the complexity and / or cost of the embodiment.

[0032] By way of example, it may be preferred that the determined fitness value includes one of a plurality of classification values. Thus, embodiments may support classifying the fitness value into easily understandable categories, which may enable the user to better understand.

[0033] Some embodiments may also include an analysis unit configured to determine usage information based on the determined fitness value, the orthodontic appliance usage information describing at least one of the following: past usage of the oral appliance; and recommendations for future usage of the oral appliance. Thus, embodiments may support providing information that helps guide oral care / processing decisions.

[0034] By way of example, the mechanical stimulation may include at least one of the following: a vibration force applied to the oral appliance to vibrate at least a portion of the oral appliance; and a pulsed force applied to the oral appliance to modify the momentum of at least a portion of the oral appliance. For example, a vibrating electric toothbrush may be used to apply vibration to the oral appliance. Thus, embodiments may support using pre-existing and widely available devices to provide mechanical stimulation. That is, embodiments may use existing devices for a new purpose to support the implementation of the proposed concept(s). In this way, embodiments may be implemented inexpensively and simply.

[0035] The system can be positioned away from the oral appliance worn by the subject. In this way, a user (such as a dental professional) can have a suitably arranged system that can receive fitness value information at a location positioned away from the system for evaluating the fitness of the oral appliance worn by the subject. Thus, embodiments can enable a user to use a local system (which can include, for example, a portable display device such as a laptop computer, a tablet computer, a mobile phone, a PDA, etc.) to evaluate the fitness of the oral appliance worn by the subject. By way of example, embodiments can provide an application for a mobile computing device, and the application can be executed and / or controlled by a user of the mobile computing device.

[0036] The system can also include: a server device that includes a system for evaluating the fitness of the oral appliance worn by the subject; and a client device that includes a user interface. Thus, dedicated data processing means can be employed to evaluate the fitness of the oral appliance worn by the subject, thereby reducing the processing requirements or capabilities of other components or devices of the system.

[0037] The system can also include a client device, where the client device includes processor means and a display unit. In other words, a user (such as a dentist or a wearer of the oral appliance) can have a suitably arranged client device (such as a laptop computer, a tablet computer, a mobile phone, a PDA, etc.) that processes the received data to evaluate the fitness of the oral appliance and generates display control signals. By way of pure example, embodiments can thus provide a monitoring or observation system that is capable of monitoring the fitness of the oral appliance worn by the subject from a single location, where communication between the subject and the monitoring user (such as a dentist or a doctor) is provided, and its functionality can be extended or modified, for example, in accordance with the concepts proposed.

[0038] It should be understood that, depending on the predefined constraints and / or the availability of processing resources, the processing capabilities can thus be distributed in different ways throughout the system.

[0039] According to yet another aspect of the present invention, there is provided an oral appliance that includes a system for evaluating the fitness of the oral appliance according to the proposed embodiments. For example, the oral appliance can include a mouthguard, an oral piece, a dental orthosis, or an orthodontic appliance.

[0040] Thus, one or more of the proposed concepts can be used in a range of different oral appliances. Accordingly, embodiments can have a wide range of applications in the field of oral health or dental care.

[0041] Embodiments can be used in combination with conventional / existing oral appliances. In this way, the embodiments can be integrated into conventional devices / products in order to improve and / or expand their functions and capabilities. Accordingly, the proposed embodiments can provide an improved oral appliance.

[0042] According to an example of another aspect of the present invention, there is provided a method for evaluating the fitness of an oral appliance worn by a subject, the method comprising:

[0043] measuring the mechanical response of the oral appliance to mechanical stimuli; and

[0044] analyzing the measured mechanical response to determine a fitness value that describes the fitness of the oral appliance to the subject.

[0045] According to another aspect, there is provided a computer program product for evaluating the fitness of an oral appliance worn by a subject, wherein the computer program product comprises a computer-readable storage medium having computer-readable program code embodied therein, the computer-readable program code being configured to perform all of the steps of the proposed embodiments.

[0046] Accordingly, a computer system can also be provided, the computer system comprising: a computer program product according to the proposed embodiments; and one or more processors adapted to perform the method according to the proposed concepts by executing the computer-readable program code of the computer program product.

[0047] These and other aspects of the invention will become apparent and be elucidated with reference to the embodiments (s) described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] For a better understanding of the present invention, and to more clearly show how the present invention may be implemented, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0049] Figure 1 is a simplified schematic block diagram of a dental aligner according to the proposed embodiments;

[0050] Figure 2 is a simplified schematic block diagram of a tooth oral appliance worn by a subject and contacted by a system for evaluating the fitness of the oral appliance according to the proposed embodiments;

[0051] Figures 3A to 3C is a graph depicting the simulated variation of displacement, maximum displacement, and acceleration in response to a small perturbation for various preload F0 values of an oral appliance;

[0052] Figure 4is a simplified flowchart of a method for evaluating the fit of an oral appliance worn by a subject; and

[0053] Figure 5 is a simplified block diagram of a computer that can employ one or more portions of the embodiments. Detailed Description

[0054] The present invention will be described with reference to the accompanying drawings.

[0055] It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems, and methods, are intended for illustrative purposes only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, systems, and methods of the present invention will become better understood from the following description, the appended claims, and the drawings. The fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used advantageously.

[0056] From a study of the drawings, the disclosure, and the appended claims, those skilled in the art will appreciate and realize variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0057] It should be understood that the drawings are merely schematic and are not drawn to scale. It should also be understood that in all the drawings, the same reference numerals are used to indicate the same or similar parts.

[0058] Embodiments according to the present disclosure relate to various schemes, solutions, concepts, designs, methods, and systems related to assisting in evaluating the fit of an oral appliance to a subject (i.e., the wearer). According to the proposed concepts, many possible solutions can be implemented individually or jointly. That is, although these possible solutions may be described separately below, two or more of these possible solutions can be implemented in one combination or another.

[0059] The present invention proposes concepts for assisting and / or improving the evaluation of the fit of an oral appliance. In particular, embodiments can provide a system, device, and / or method that measures the mechanical response of an oral appliance to mechanical stimuli applied to the oral appliance (when worn by a subject, such as a patient or user). The measured mechanical response is analyzed to determine a fit value that describes the fit of the oral appliance to the subject. In other words, it is proposed that the mechanical response of the oral appliance to mechanical stimuli indicates the fit of the oral appliance to the subject.

[0060] Embodiments propose that the measured mechanical response of an oral appliance can be analyzed to determine a fitness value that describes the fitness of the oral appliance to a subject wearing the oral appliance in the mouth. The mechanical response can be stimulated by an oscillatory force or an impulsive force (e.g., a sudden impact / hit) applied to the oral appliance. By way of pure example, the mechanical stimulation can be applied to the oral appliance by the user (e.g., by clenching their teeth), by a stimulation unit integrated into the oral appliance (e.g., a vibration unit), and / or by a separate device (e.g., a vibrating electric toothbrush or a dental drill).

[0061] The proposed concept can be applied, for example, to dental aligners, oral-piece toothbrushes, mouthguards, and orthodontic appliances. In other words, the proposed concept can be incorporated into a wide range of oral care / hygiene devices to provide the user with an improved assessment and understanding of their fitness. Thus, the proposed embodiments can improve dental care / treatment by providing relevant and useful information that can be used to make more informed care / treatment decisions.

[0062] Reference Figure 1 , shows a simplified schematic block diagram of a dental aligner 100 according to the proposed embodiments. The aligner 100 is adapted to be inserted into a user's mouth and worn for an extended period of time. The aligner is adapted to apply a force to the wearer's teeth when worn, which causes one or more of the user's teeth to move over time (i.e., be realigned).

[0063] A system for evaluating the fitness of the dental aligner 100 is integrated with the dental aligner. Specifically, the dental aligner 100 includes some components of the system, and these components communicate with other system components (e.g., via short-range and / or long-range communication links).

[0064] The system includes a stimulation unit 105 that is configured to generate a mechanical stimulation and apply it to the dental aligner 100. In this embodiment, the stimulation unit is provided in the dental aligner 100 and includes a vibration device (such as a motor and a biasing pivot) that is adapted to vibrate the dental aligner 100. Thus, the vibration device 105 generates an oscillatory force and applies it to the dental aligner 100 to cause at least a portion of the dental aligner 100 to vibrate. Thus, the mechanical stimulation includes an oscillatory force.

[0065] The system further includes a sensor unit 110 configured to measure the mechanical response of the dental appliance to mechanical stimuli (i.e., vibratory forces) applied to the dental appliance 100. Specifically, the sensor unit 110 is integrated within the dental appliance 100 and includes a motion sensor 115 configured to measure at least one of the following: the magnitude of acceleration; the magnitude of velocity; the magnitude of displacement; and the vibration frequency of the dental appliance 100. In this example, the motion sensor 115 includes a piezoelectric transducer circuit configured to convert changes in parameters of the oral appliance (such as momentum, acceleration, etc.) into electrical signals. In an alternative embodiment of this embodiment, other types / forms of motion sensors may be employed, such as accelerometers, gyroscopes, or IMUs.

[0066] In Figure 1 the example of, the sensor unit 110 is further configured to detect the application (i.e., start) of a mechanical stimulus to the dental appliance 100, and in response to detecting the application of a mechanical stimulus to the dental appliance 100, the sensor unit 110 measures the mechanical response of the dental appliance to the detected mechanical stimulus. This can help reduce power consumption and / or inaccurate measurements, such as by avoiding detecting incorrect / irrelevant measurements.

[0067] The system further includes a processor device 120 and a communication unit 130.

[0068] The communication unit 130 is configured to transmit the measured mechanical response to the processor device 120 via one or more communication links (i.e., a communication network). Specifically, the communication unit 130 includes a wireless communication interface adapted to transmit the mechanical response to the Internet via a wireless connection. By way of example, the wireless connection may include a short-range to medium-range communication link. For the avoidance of doubt, a short-range to medium-range communication link should be understood to be a short-range or medium-range communication link having a range of up to approximately 100 meters. In a short-range communication link designed for very short communication distances, signals typically propagate from a few centimeters to several meters, while in a medium-range communication link designed for short to medium communication distances, signals typically propagate up to 100 meters. Examples of short-range wireless communication links include ANT+, Bluetooth, Bluetooth Low Energy, IEEE 802.15.4, ISA100a, Infrared (IrDA), ISM band, Near Field Communication (NFC), RFID, 6LoWPAN, UWB, WirelessHART, WirelessHD, Wireless USB, ZigBee. Examples of medium-range communication links include Wi-Fi, Z-Wave.

[0069] The processor device 120 receives the transmitted mechanical response from the Internet 140 via a wireless connection, which may include a short-range to medium-range communication link.

[0070] The processor device 120 is configured to analyze the measured mechanical response (detected by the motion sensor 110) to determine a fitness value that describes the fitness of the oral appliance to the subject. Specifically, the processor device 120 is configured to compare the measured mechanical response with a predetermined threshold; and determine the fitness value based on the comparison result. For example, the predetermined threshold can be configured to distinguish a tight or loose fit of the dental orthosis 100. Depending on the comparison result, it can then be determined which of two classification values (e.g., tight or loose, or correct or incorrect) is assigned to the fitness value.

[0071] Other pairs of classification values can be employed, such as correct and incorrect fit), and / or a set of possible classifications can include more than two classification values / fields. For example, multiple thresholds can be employed to distinguish ranges of fitness values such that the mechanical response can be classified into one of a range of possible classification values (e.g., a scale of values ranging from 1 to 10).

[0072] The processor device 120 is configured to transmit the determined fitness value via the Internet 140 to a portable computing device 150 (such as a tablet computer, smartphone, or laptop computer). In this way, information about the determined fitness value can be provided to the user of the system and / or the wearer of the dental orthosis.

[0073] Figure 1 The system further includes an analysis unit 160 that can communicate with the processor device 120 and the portable computing device 150 via the Internet 140. The analysis unit 160 is configured to obtain the determined fitness value (e.g., from the processor device 120 or the portable computing device 150) and analyze the fitness value to determine orthosis usage information that describes at least one of the following: past use of the oral appliance; and recommendations for future use of the oral appliance. For example, if the fitness value is not as expected (according to a predetermined prediction and / or calculation), the analysis unit 160 can infer that the dental orthosis has not been used according to the instructions or guidance. This can facilitate the generation and provision of information to guide care / processing decisions.

[0074] Now referring to Figure 2 , a simplified schematic block diagram of a tooth oral appliance 200 (e.g., a gingival appliance or a bruxism guard) worn by a subject and contacted by a system 210 for evaluating the fitness of the oral appliance 200 is shown. For ease of illustration, Figure 2 the mouth of the subject is not shown in

[0075] The oral appliance 200 is inserted into a user's mouth and worn to protect teeth and / or gums from damage. Preferably, the oral appliance 200 closely conforms to the shape of the teeth and gums of the subject (i.e., the wearer) to minimize the gap between them.

[0076] A system 210 for evaluating the fit of the oral appliance 200 includes a separate, stand-alone handheld system 210 that is configured to be placed against the oral appliance during use.

[0077] According to the concepts presented, mechanical stimulation is applied to the oral appliance 200, and the system 210 is configured to analyze the measured mechanical response to the mechanical stimulation in order to determine a fit value that describes the fit of the oral appliance to the subject.

[0078] In Figure 2 an embodiment, mechanical stimulation is applied to the oral appliance 200 by using a vibrating electric toothbrush 224 (which may already be owned and available to the wearer of the oral appliance 200). As indicated by arrow 222, the vibrating electric toothbrush 224 is held or pushed against the oral appliance in order to apply a vibrating force 222 to the oral appliance 200.

[0079] The system 210 includes a sensor unit 230 that measures the mechanical response of the oral appliance to the mechanical stimulation (i.e., the vibrating force 222) applied to the oral appliance 200 by the electric toothbrush 224. A processor device 240 of the system 210 analyzes the measured mechanical response to determine a fit value that describes the fit of the oral appliance to the subject. An output interface 250 of the system is configured to communicate information describing the determined fit value to the subject (e.g., provide an auditory indication and / or a visual indication).

[0080] The output interface 250 may also perform additional functions. For example, in Figure 2 an embodiment, the output interface 250 is configured to output an instruction for prompting the subject to press / hold the vibrating electric toothbrush 224 against the oral appliance. Based on the analysis of the measured mechanical response, it can also be determined whether the vibrating electric toothbrush 224 is pressed against the oral appliance 200 too tightly or too lightly. Then, the output interface 240 can also be used to provide feedback / instructions to the subject, which can guide the subject to press more tightly / more lightly, for example. The instructions communicated by the output interface 250 may also include guidance for instructing the subject to perform a predetermined jaw movement or posture, thereby helping to more precisely measure the mechanical response of the oral appliance 200.

[0081] From the above embodiments, it can be understood that one or more concepts (one or more) for evaluating the fit of an oral appliance are provided. Such evaluation can be achieved remotely and in an objective, non-intrusive manner. The embodiments can also facilitate providing objective advice (one or more), such as advice on replacing the oral appliance.

[0082] Specifically, it is proposed that the force between the oral appliance and the wearer's teeth / gums can be used as an indicator or measure of the fit (e.g., a tighter fit = a greater force). Specifically, this force will affect the mechanical response of the oral appliance to mechanical stimuli. By measuring and analyzing the mechanical response to the stimuli, the (change in) orthodontic appliance fit can be evaluated.

[0083] The arrangement of one or more components for applying mechanical stimuli and / or measuring mechanical responses can be provided within the oral appliance (i.e., integrated therein) or provided external to the oral appliance.

[0084] By way of further summarizing the proposed concept(s), exemplary embodiments can include the following:

[0085] A device for measuring the response of an oral appliance to mechanical stimuli, such as an accelerometer or IMU;

[0086] A device for providing mechanical stimuli to the oral appliance, or alternatively, a device for detecting whether a stimulus has been provided or for instructing the user to provide a stimulus (e.g., a biting motion);

[0087] A processor device for calculating a measure of the fit from the measured response; and

[0088] A device for providing information to the user and / or dental professional based on the determined fit, such as a notification to replace the oral appliance, information regarding the level of wear compliance, etc.

[0089] Additional embodiments will now be described by further explaining the proposed concept(s) and various implementation options.

[0090] - Exemplary Embodiment A - Stimulus-Response Measurement Using an Electric Toothbrush Resonant force or acceleration is picked up by a sensor device in an electric toothbrush that induces vibration of the oral appliance.

[0091] In this embodiment, the oral appliance may not include any additional elements related to providing the stimulus and measuring the response of the oral appliance. Instead, an external device / system can be used to determine the mechanical response of the oral appliance. Specifically, the electric toothbrush can be placed with the bristles or the back of the brush head against the oral appliance. The vibration of the electric toothbrush then provides a stimulus to the oral appliance, and the response can be measured via the brush head platen of the electric toothbrush.

[0092] Electric toothbrushes that can measure the platen reaction force (pattern) exerted on the brush head platen by the moving teeth are known. Simulations show that with existing IMU sensors in such toothbrushes (minimum resolution ≈ 0.0003g), acceleration amplitudes ≥ 0.01g can be measured.

[0093] Additional data averaging and filtering techniques (e.g., moving average, high / low band pass, baseline subtraction, etc.) can be used to resolve orthodontic movement-related accelerations from general toothbrush accelerations.

[0094] Exemplary embodiment B - Stimulation response measurement within an oral appliance.

[0095] In this embodiment, a sensor device is incorporated into the oral appliance for stimulation response measurement. Data containing sensed stimulation response measurements can be transmitted via a wireless communication link to a device for analysis. That is, the oral appliance includes a sensor (e.g., an accelerometer) for measuring a mechanical response and an actuator (e.g., an electric oscillator or a piezoelectric actuator) for providing a defined mechanical stimulation. Alternatively, actuation and measurement can be provided by a single element, such as a piezoelectric transducer. Here, stimulation and response measurements can be provided at one or several (different) locations on the aligner. The response measurement data is then wirelessly transmitted to a receiver, such as a smartphone or a laptop computer.

[0096] Alternatively, the response measurements can be temporarily stored in the memory of the oral appliance and read out later using a docking station provided by the oral appliance. The docking station can also be used to charge the power supply of the oral appliance, which is required for the actuator and the sensor. The docking station can be connected to a smartphone and / or a cloud server via the Internet.

[0097] Analysis of the response measurements is performed by a processor device (in a smartphone, docking station, or cloud server). This can provide a measure of the fitness of the oral appliance or a measure of how the fitness changes over time. Based on this assessment, a notification can be provided to the wearer of the oral appliance and / or a dental professional that the oral appliance should be changed or replaced. Additionally, compliance with wearing the oral appliance can be monitored by periodically performing response measurements. When the oral appliance is not being worn, the response will be significantly different from what is expected when it is worn.

[0098] Exemplary embodiment C - User-initiated stimulation and response measurement using a sensor in an oral appliance.

[0099] In this embodiment, the oral appliance may include only a sensor unit (such as an accelerometer) for measuring the mechanical response to mechanical stimuli. Without using an actuator, the mechanical stimuli can be provided by the wearer of the oral appliance, such as in the form of chewing movements / jaw movements or tooth vibrations. These'stimulus events' can occur randomly / actively, or can be explicitly requested via the UI presented to the user. In the latter case, the stimulus can also be the user tapping on the aligner. Although these stimuli may not be as controllable / standardized as when provided via an actuator, they are still sufficient to reliably determine the mechanical response of the oral appliance. This is because the stimulus movements can be quite repeatable and are typically 'pulse stimuli' (i.e., short, sudden forces). The latter means that some response characteristics, such as the resonant frequency and the decay time / damping, can be determined repeatedly.

[0100] Exemplary embodiment D - Oral appliance design for tight or loose fit indication

[0101] In another embodiment, the oral appliance can be designed such that when it transitions from a tight fit to a loose fit, a change in the mechanical response can be detected or significantly enhanced.

[0102] For example: The back of the dental aligner can be bent outwards, i.e., away from the teeth. Similarly, for the target tooth, the gap between the back of the aligner and the tooth can be increased. This will ensure that the back of the aligner is disengaged from the tooth under loose fit conditions, thus giving a clearly distinguishable mechanical response.

[0103] Other aligner properties can also vary locally (such as the thickness of the back of the aligner, etc.) to provide a changed mechanical response to the stimulus when the aligner fit changes.

[0104] To demonstrate the principle of the proposed concept(s), a minimal model of a dental aligner system has been considered. Here, only the interaction between a single tooth attached to the gum and a segment of the oral appliance is modeled. To simulate the connection of this segment to the rest of the oral appliance, the sides are fixed. In addition, the force exerted by the oral appliance on the tooth is modeled as a uniformly distributed load on the initially flat front surface of the tooth.

[0105] At each time point, the aligner segment applies a preload F0 on the tooth surface. To evaluate the mechanical response (here displacement or acceleration), an oscillating probe pulse probe(t) is applied with a force magnitude f0 << F0. Thus, here, the response of the front of the aligner is measured relative to a small perturbation. This model uses the order-of-magnitude dimensions and properties of a real oral appliance - tooth system to show the feasibility of the concept.

[0106] Based on the above, a set of computational simulations have been performed to:

[0107] (i) Measuring the response to a static load (F0) - Figure 3A Displacements and stresses on the aligner geometry for different F0 values are shown. The measured static displacement of the tooth centroid (tooth activation) is shown.

[0108] (ii) For some static loads, time - dependent simulations are performed to measure the corresponding vibration response on the front of the aligner. Figure 3B The combined amplitude of the vibration displacements for different pre - loads is shown. The sharp change in the displacement amplitude at ≈2N is due to the loss of contact (disengagement) of the tooth - gum - front of the aligner with the back of the aligner. Figure 3C The variation of the acceleration on the front of the aligner with time is shown for two different static loads, F0 = 1N (i.e., loose fit) and F0 = 2.5N (i.e., tight fit), where the probe - on time is 0.5 seconds. For a probe frequency of 100Hz (the frequency of an electric toothbrush is 265Hz), for the tight fit (F0 = 2.5N), the average aligner acceleration is ≈0.03g, and for the loose fit (F0 = 1N), the average aligner acceleration is ≈0.3g. Thus, it can be seen that as the static load decreases, the average aligner acceleration transitions from a low - displacement / acceleration system to a system with higher values.

[0109] Therefore, it has been demonstrated from the simulations that the displacement change in response to a perturbation enables the inference of the pre - load F0 and thus the inference of the fit of the oral appliance. Similar inferences can be drawn from the acceleration change in response to the perturbation.

[0110] Reference Figure 4 depicts a flowchart of a method 400 for evaluating the fit of an oral appliance worn by a subject. The method begins with a step 410 of applying a mechanical stimulus to the oral appliance. The applied stimulus can be vibratory (i.e., exhibiting a vibration period) or can include a pulse (i.e., a sudden force of short duration).

[0111] Next, in step 420, the mechanical response of the oral appliance to the mechanical stimulus is measured (using one or more sensors).

[0112] Finally, in step 430, the measured mechanical response is analyzed to determine a fit value that describes the fit of the oral appliance to the subject.

[0113] From the above description of various concepts and embodiments, it can be understood that the concept of evaluating the fit of an oral appliance worn by a subject is proposed. The proposed concept is based on the recognition that the fit of the oral appliance to the teeth and / or gums of the wearer will affect the mechanical response of the oral appliance to a mechanical stimulus. It has been proposed that by analyzing such mechanical responses, the fit of the oral appliance can be determined. This can provide an objective and accurate measure of the fit.

[0114] Accordingly, such proposals facilitate a simple and reliable assessment of the fit of an oral appliance worn by a subject.

[0115] By way of example only, the illustrative embodiments can be used in many different types of clinical, medical, or subject-related environments, such as hospitals, doctor's offices, wards, nursing homes, private residences, and the like.

[0116] Figure 5 An example of a computer 50 in which one or more portions of the embodiments can be employed is illustrated. The various operations discussed above can utilize the capabilities of the computer 50. For example, one or more portions of a system for providing an assessment of the fit of an oral appliance can be incorporated into any of the elements, modules, applications, and / or components discussed herein. In this regard, it should be understood that the system functional blocks can operate on a single computer or can be distributed across several computers and locations (e.g., via an Internet connection), such as a cloud-based computing infrastructure.

[0117] The computer 50 includes, but is not limited to, a PC, a workstation, a laptop computer, a PDA, a handheld device, a smartphone, a smartwatch, a server, a storage device, and the like. Generally speaking, in terms of the hardware architecture, the computer 500 can include one or more processors 51, a memory 52, and one or more I / O devices 53, which are communicatively coupled via a local interface (not shown). The local interface can be, for example but not limited to, one or more buses or other wired or wireless connections, as is known in the art. The local interface can have additional elements, such as controllers, buffers (cache), drivers, repeaters, and receivers, to enable communication. In addition, the local interface can include address, control, and / or data connections to enable proper communication among the above-described components.

[0118] The processor 51 is a hardware device for executing software that can be stored in the memory 52. The processor 51 can actually be any custom or commercially available processor, a central processing unit (CPU), a digital signal processor (DSP), or an auxiliary processor among several processors associated with the computer 50, and the processor 51 can be a semiconductor-based microprocessor (in the form of a microchip) or a microprocessor.

[0119] The memory 52 may include any one or a combination of volatile memory elements (e.g., random access memory (RAM), such as dynamic random access memory (DRAM), static random access memory (SRAM), etc.) and non-volatile memory elements (e.g., ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic tape, compact disc read-only memory (CD-ROM), magnetic disk, floppy disk, cassette tape, etc.). In addition, the memory 52 may incorporate electronic, magnetic, optical, and / or other types of storage media. It should be noted that the memory 52 may have a distributed architecture, where various components are located remotely from each other but can be accessed by the processor 51.

[0120] The software in the memory 52 may include one or more separate programs, each program including an ordered list of executable instructions for implementing logical functions. According to an exemplary embodiment, the software in the memory 52 includes a suitable operating system (O / S) 54, a compiler 56, source code 55, and one or more applications 57. As shown, the application 57 includes a plurality of functional components for implementing the features and operations of the exemplary embodiment. According to an exemplary embodiment, the application 57 of the computer 50 may represent various applications, computing units, logics, functional units, processes, operations, virtual entities, and / or modules, but the application 57 is not meant to be limiting.

[0121] The operating system 54 controls the execution of other computer programs and provides scheduling, input / output control, file and data management, memory management, communication control, and related services. The inventors anticipate that the application 57 for implementing the exemplary embodiment may be applicable to all commercially available operating systems.

[0122] The application 57 may be a source program, an executable program (object code), a script, or any other entity including a set of instructions to be executed. When it is a source program, the program is typically translated via a compiler (e.g., compiler 56), assembler, interpreter, etc., which may or may not be included in the memory 52 to operate correctly in conjunction with the O / S 54. In addition, the application 57 may be written in an object-oriented programming language having data and method classes, or a procedural programming language having routines, subroutines, and / or functions, such as but not limited to C, C++, C#, Pascal, BASIC, API calls, HTML, XHTML, XML, ASP scripts, JavaScript, FORTRAN, COBOL, Perl, Java, ADA,.NET, and so on.

[0123] The I / O device 53 may include input devices such as, but not limited to, a mouse, a keyboard, a scanner, a microphone, a camera, etc. In addition, the I / O device 53 may also include output devices such as, but not limited to, a printer, a display, etc. Finally, the I / O device 53 may also include devices for transmitting inputs and outputs such as, but not limited to, a NIC or a modem / demodulator (for accessing remote devices, other files, devices, systems, or networks), a radio frequency (RF) or other transceiver, a telephone interface, a bridge, a router, etc. The I / O device 53 also includes components for communicating over various networks such as the Internet or an intranet.

[0124] If the computer 50 is a PC, a workstation, a smart device, etc., the software in the memory 52 may also include a basic input / output system (BIOS) (omitted for simplicity). The BIOS is a set of basic software routines that initialize and test the hardware at startup, start the O / S 54, and support data transfer between hardware devices. The BIOS is stored in a type of read-only memory such as ROM, PROM, EPROM, EEPROM, etc., so that when the computer 800 is activated, the BIOS can be executed.

[0125] When the computer 50 is running, the processor 51 is configured to execute the software stored in the memory 52, transfer data to and from the memory 52, and generally control the operation of the computer 50 according to the software. The application 57 and the O / S 54 are all or partially read by the processor 51, may be buffered within the processor 51, and then executed.

[0126] When the application 57 is implemented in software, it should be noted that the application 57 can be stored on almost any computer-readable medium for use by or in conjunction with any computer-related system or method. In the context of this document, a computer-readable medium can be an electronic, magnetic, optical, or other physical device or apparatus that can contain or store a computer program for use by or in conjunction with a computer-related system or method.

[0127] The application 57 can be embodied in any computer-readable medium and used by or in conjunction with an instruction execution system, apparatus, or device such as a computer-based system, a system including a processor, or other systems that can obtain and execute instructions from the instruction execution system, apparatus, or device. In the context of this document, a "computer-readable medium" can be any device that can store, communicate, propagate, or transmit a program used by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium.

[0128] The proposed concept(s) can be implemented in hardware, software, or a combination of both (e.g., as firmware running on a hardware device). To the extent that an embodiment is implemented partially or fully in software, the functional steps shown in the process flow diagrams can be performed by a suitably programmed physical computing device, such as one or more central processing units (CPUs) or graphics processing units (GPUs). Each process and the individual component steps shown in its flowchart can be performed by the same or different computing devices. According to an embodiment, a computer-readable storage medium stores a computer program comprising computer program code configured to cause one or more physical computing devices to perform the encoding or decoding method as described above when the program is run on the one or more physical computing devices.

[0129] The storage medium can include volatile and non-volatile computer memories such as RAM, PROM, EPROM, and EEPROM, optical discs (such as CDs, DVDs, BDs), and magnetic storage media (such as hard disks and tapes). The various storage media can be fixed within the computing device or can be transportable, such that one or more programs stored thereon can be loaded into the processor.

[0130] To the extent that an embodiment is implemented partially or fully in hardware, Figure 1 and Figure 2 the blocks shown in the block diagrams can be separate physical components, or logical subdivisions of a single physical component, or can all be implemented in an integrated manner in one physical component. The function of one block shown in the drawings can be divided among multiple components in an implementation, or the functions of multiple blocks shown in the drawings can be combined in a single component in an implementation. Hardware components suitable for embodiments of the present invention include, but are not limited to, conventional microprocessors, application-specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs). One or more blocks can be implemented as a combination of dedicated hardware performing some functions and one or more programmed microprocessors and associated circuitry performing other functions.

[0131] Upon study of the drawings, disclosure, and appended claims, those skilled in the art can understand and implement variations of the disclosed embodiments when practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may implement the functions of several items recited in the claims. The fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used advantageously. If a computer program is discussed above, it may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium provided together with or as part of other hardware, but it may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. If the term "adapted to" is used in the claims or the specification, it should be noted that the term "adapted to" is intended to be equivalent to the term "configured to". Any reference signs in the claims shall not be construed as limiting the scope.

[0132] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of instructions that include one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the functionality involved. It will also be noted that each block of the block diagrams and / or flowchart illustrations, and combinations of blocks in the block diagrams and / or flowchart illustrations, can be implemented by a system based on dedicated hardware that performs the specified functions or acts, or by a combination of dedicated hardware and computer instructions.

Claims

1. A system for evaluating the fit of an oral appliance (100) worn by a subject, the system comprising: A sensor unit (110) configured to measure the mechanical response of the oral appliance to a mechanical stimulus applied to the oral appliance; And A processor device (120) configured to analyze the measured mechanical response to determine a fit value that describes the fit of the oral appliance to the subject.

2. The system according to claim 1, wherein the sensor unit comprises: A motion sensor (115) configured to measure at least one of: the magnitude of the acceleration, the magnitude of the velocity, the magnitude of the displacement, and the vibration frequency, amplitude, and frequency of at least a portion of the oral appliance.

3. The system according to claim 1 or 2, wherein the sensor unit comprises: At least one of: an accelerometer; a gyroscope; An inertial measurement unit IMU and a piezoelectric transducer circuit configured to convert a parameter change of at least a portion of the oral appliance into an electrical signal, And wherein the processor device is configured to convert the electrical signal into a fit value.

4. The system according to any one of claims 1 to 3, wherein the oral appliance (100) comprises the sensor unit (110), And optionally, wherein: The oral appliance is positioned away from the processor device (120); and the system further comprises a communication unit (130) configured to transmit the measured mechanical response to the processor device.

5. The system according to any one of claims 1 to 4, wherein the sensor unit (110) is further configured to detect the application of a mechanical stimulus to the oral appliance (100), and wherein in response to detecting the application of a mechanical stimulus to the oral appliance, the sensor unit is configured to measure the mechanical response of the oral appliance to the detected mechanical stimulus.

6. The system according to any one of claims 1 to 5, further comprising: An output interface (150) configured to output an instruction for prompting the subject to provide the mechanical stimulus to the oral appliance, And preferably, wherein the instruction comprises a guidance that instructs the subject to perform a predetermined jaw movement or posture.

7. The system according to any one of claims 1 to 6, wherein the system further comprises: A stimulus unit (105) configured to generate the mechanical stimulus and apply the mechanical stimulus to the oral appliance.

8. The system according to claim 7, wherein the stimulus unit (105) comprises at least one of: A piezoelectric transducer adapted to apply a force to at least a portion of the oral appliance; A vibration device adapted to vibrate at least a portion of the oral appliance; and A pulse device adapted to apply a pulsed force to at least a portion of the oral appliance.

9. The system according to any one of claims 1 to 8, wherein the processor device (120) is configured to: compare the measured mechanical response with a predetermined threshold; and determine a fitness value based on the comparison result.

10. The system according to any one of claims 1 to 9, wherein the processor device (12) is configured to compare the measured mechanical response with one or more thresholds and determine a fitness value based on the comparison result. Preferably, the determined fitness value includes one of a plurality of classification values.

11. The system according to any one of claims 1 to 10, further comprising: an analysis unit (160) configured to determine usage information based on the determined fitness value, the usage information describing at least one of the following: past usage of the oral appliance; and a recommendation for future usage of the oral appliance.

12. The system according to any one of claims 1 to 11, wherein the mechanical stimulus includes at least one of the following: a vibration force (222) applied to the oral appliance to vibrate at least a portion of the oral appliance; and an impulse force applied to the oral appliance to modify the momentum of at least a portion of the oral appliance.

13. An oral appliance comprising the system according to any one of claims 1 to 12 for evaluating the fitness of the oral appliance worn by a subject.

14. A method (400) for evaluating the fitness of an oral appliance worn by a subject, the method comprising: measuring (420) the mechanical response of the oral appliance to a mechanical stimulus; and analyzing (430) the measured mechanical response to determine a fitness value describing the fitness of the oral appliance to the subject.

15. A computer program comprising computer program code means adapted to implement the method according to claim 14 when the computer program is run on a computer.

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