Oral irrigator with bite sensing

Abstract

A system for oral rinsing includes a fluid delivery tube (102) having a proximal end and a distal end. The proximal end is used to receive oral rinsing fluid. A nozzle (104) is disposed at the distal end of the fluid delivery tube. The system also includes: an interdental sensor (2002) for detecting whether the nozzle is in the interdental space; and a motion sensor (2004) for measuring the displacement of the nozzle. A processor is configured to determine whether the nozzle (104) is moving along the occlusal surface of a tooth based on the displacement of the nozzle being greater than a critical distance and the interdental sensor (2002) not detecting interdental space during the displacement of the nozzle, wherein the critical distance indicates the length of the tooth.

Description

Technical Field

[0001] This invention relates to the field of oral irrigators. It also relates to a combined brushing and oral irrigator device. Background Technology

[0002] Oral hygiene includes keeping the occlusal surfaces and lateral surfaces of the teeth clean. The occlusal surfaces are the surfaces of the teeth used for chewing and / or grinding, while the lateral surfaces are where the interdental spaces (i.e., the spaces between the teeth) are located.

[0003] To promote oral health, it is important to ensure that all tooth surfaces are thoroughly cleaned, including the interdental spaces. Studies have shown that inadequate cleaning of the interdental spaces leads to gum and periodontal disease and can cause tooth decay (i.e., Class II caries).

[0004] Dental professionals worldwide recommend that their patients use various interdental cleaning methods or devices (such as dental floss, interdental brushes, water jets, etc.) to clean between teeth. Devices exist that facilitate cleaning the interdental spaces with fluid jets. The force of the fluid jet removes plaque.

[0005] However, thorough cleaning of the occlusal surfaces differs from cleaning methods used for the interdental spaces. While interdental sensors typically detect whether a jet toothbrush is positioned to spray into the interdental spaces, they cannot detect when the toothbrush (or nozzle) is on the occlusal surface. In some cases, it is important to know that the toothbrush or flossing device is not close to the interdental spaces and gingival line (i.e., on the occlusal surface of the teeth).

[0006] Therefore, a method is needed to detect when a toothbrush and / or dental floss cleaning device is located on the occlusal surface. Summary of the Invention

[0007] This invention is defined by the independent claims. The dependent claims define advantageous embodiments.

[0008] According to an example of one aspect of the present invention, a system for oral irrigation is provided, the system comprising:

[0009] A fluid delivery tube having a proximal end and a distal end, wherein the proximal end is used to receive oral irrigation fluid;

[0010] The nozzle is located at the distal end of the fluid delivery pipe;

[0011] Interdental sensor is used to detect whether the nozzle is in the interdental space;

[0012] Displacement sensor, used to measure nozzle displacement; and

[0013] The processor is configured to determine that the nozzle is moving along the occlusal surface of the tooth based on the nozzle displacement being greater than a critical distance and the interdental sensor not detecting interdental space during the nozzle displacement, wherein the critical distance indicates the length of the tooth.

[0014] The occlusal surfaces of teeth must be treated differently than the lateral surfaces used for oral irrigation. The lateral surfaces of teeth have interdental spaces that require thorough oral irrigation; however, the occlusal surfaces do not. Unnecessary irrigation of the occlusal surfaces can result in the use of excessive amounts of irrigation fluid, which can cause discomfort to the user due to a large amount of liquid in their mouth. Therefore, it is important for oral irrigation systems to know when the system's nozzles are positioned on the occlusal side.

[0015] This can be achieved by using both interdental sensors and displacement sensors. The interdental sensor detects when the nozzle is in the interdental space. This can be done using a pressure sensor or a flow sensor. For example, the nozzle can be designed to deform when it is not in the interdental space, causing an increase in pressure and a decrease in flow. Alternatively, a set of electrodes can be used to determine when the nozzle is in the interdental space. The displacement sensor senses how far the nozzle has traveled during oral irrigation. If the nozzle has moved a distance equal to or greater than a critical distance (the length of a tooth) without encountering the interdental space, it can be assumed that the nozzle is on the occlusal side.

[0016] Oral irrigators can also be called dental water flossers, dental water sprayers, or water toothpicks.

[0017] The processor can also be configured to determine that the nozzle is moving along the side of the tooth based on the nozzle displacement being greater than a critical distance and the interdental sensor detecting the interdental space during the nozzle displacement.

[0018] The system may also include a pump configured to pump fluid through a fluid delivery pipe and a controller configured to control the pump.

[0019] The controller can be configured to implement two injection modes for controlling the pump, wherein a first injection mode is used when the processor determines that the nozzle is moving along the occlusal surface of the teeth, and wherein a second injection mode is used when the processor determines that the nozzle is moving along the lateral surface of the teeth.

[0020] Two distinct jetting modes allow users to provide adequate oral irrigation to the interdental space without using unnecessary fluid. For example, the pump can deliver fluid at low pressure and low flow rate during jetting at the occlusal surface, and change to a greater flow rate and higher pressure when the nozzle is on the side of the teeth.

[0021] The interdental sensor can be either a pressure sensor used to measure the pressure of fluid in a fluid delivery pipe or a flow sensor used to measure the flow rate of fluid in a fluid delivery pipe.

[0022] Interdental sensors may include at least two electrodes located at the tip of the nozzle.

[0023] The processor can also be configured to determine whether the nozzle is in the air.

[0024] For example, an interdental sensor can detect "interdental space" over a long period of time. This can be used to indicate that it is not actually interdental space and that the nozzle is no longer in contact with the teeth or is no longer being used.

[0025] The system may also include one or more of the following:

[0026] Force sensor, used to sense the force applied by the user between the nozzle and the teeth;

[0027] accelerometer; and

[0028] A gyroscope is used to measure the angle of a nozzle relative to a tooth.

[0029] The processor can be configured to determine that the nozzle is moving along the occlusal surface of the tooth based on a machine learning algorithm, wherein the machine learning algorithm is trained to identify the occlusal surface and the lateral surface of the tooth based on signals from at least interdental sensors and displacement sensors.

[0030] The critical distance can be at least 0.5 cm.

[0031] Typically, a tooth is about 1 cm long; however, the exact length will vary for each user and for each type of tooth. For smaller teeth, a critical distance of at least 0.5 cm may be necessary, while for larger teeth, the distance increases to about 1.5 cm.

[0032] The system may also include:

[0033] The toothbrush head includes multiple bristles.

[0034] The toothbrush head also includes a nozzle.

[0035] Therefore, the device can be integrated into a combination of brushing and oral rinsing heads.

[0036] The oral hygiene system may also include a motor for controlling the head section of the toothbrush handle during brushing motion, and wherein a controller is configured to control the motor.

[0037] The controller can be configured to implement two brushing modes for controlling the motor, wherein a first brushing mode is used when the processor determines that the nozzle is moving along the occlusal surface of the teeth, and wherein a second brushing mode is used when the processor determines that the nozzle is moving along the lateral surface of the teeth.

[0038] These brushing patterns differ, for example, in the rotation speed applied to the rotating brush head.

[0039] The present invention also provides a method for determining whether an oral irrigation system is located on the occlusal surface of a tooth, the method comprising:

[0040] Determine the displacement of the nozzles in the oral irrigation system;

[0041] Determine if the nozzle is in the interdental space; and

[0042] The following steps are used to determine if the nozzle is moving along the occlusal surface of the teeth:

[0043] Determine that the nozzle displacement is greater than the critical distance and that the nozzle has not yet been positioned in the inter-tooth space during the nozzle displacement.

[0044] The method may also include determining that the nozzle is moving along the side of the tooth by determining that the nozzle displacement is greater than a critical distance and that the nozzle was once positioned in the interdental space during the displacement of the nozzle.

[0045] The method may also include implementing two spray modes for controlling the pump of the oral irrigation system, wherein a first spray mode is used when it is determined that the nozzle is moving along the occlusal surface of the teeth, and wherein a second spray mode is used when it is determined that the nozzle is moving along the lateral surface of the teeth. Thus, different spray modes are used depending on the nozzle position.

[0046] Similarly, the method may also include implementing two brushing modes for controlling the motor driving the toothbrush head, wherein a first brushing mode is used when it is determined that the nozzle is moving along the occlusal surface of the teeth, and wherein a second brushing mode is used when it is determined that the nozzle is moving along the lateral surface of the teeth. Thus, different brushing modes are used depending on the position of the nozzle and the toothbrush head (in a system with an integrated rinsing system and toothbrush head).

[0047] This method is implemented in software. Therefore, the present invention also provides a computer program including computer program code, which, when executed by a processor, causes a processing system to perform all the steps of the method. The present invention also provides a processor on which the computer program is stored.

[0048] The present invention also provides a handle for an oral irrigation system, wherein the handle comprises:

[0049] An interface for connecting the handle to the oral irrigation head;

[0050] Fluid delivery tubing is used to deliver fluid to the oral irrigation head;

[0051] The pump is configured to pump fluid into the fluid delivery pipe (102) based on the pump configuration; and

[0052] The aforementioned processor is used to control the pump.

[0053] Other heads can also be attached to the handle, such as a combination toothbrush and oral rinsing head.

[0054] These and other aspects of the invention will become apparent from the embodiments described below. Attached Figure Description

[0055] To better understand the invention and to more clearly illustrate how to implement it, reference will now be made to the accompanying drawings by way of example only, wherein:

[0056] Figure 1 A schematic diagram of the head section of a toothbrush is shown;

[0057] Figure 2 A schematic diagram of a toothbrush with an oral irrigator is shown;

[0058] Figure 3 A schematic diagram of a toothbrush with an oral irrigator and an air inlet is shown;

[0059] Figure 4 This shows a first example of a nozzle design;

[0060] Figure 5 A second example of nozzle design is shown;

[0061] Figure 6 A third example of nozzle design is shown;

[0062] Figure 7 A fourth example of nozzle design is shown;

[0063] Figure 8 The fifth example of a nozzle design is shown;

[0064] Figure 9 A nozzle with a mechanical valve in different states is shown;

[0065] Figure 10 The force balance on the mechanical valve is shown in a simplified schematic diagram;

[0066] Figure 11 The brush head of the combined brushing and flossing device is shown when used on the teeth.

[0067] Figure 12 A brush head for a combined brushing and flossing device with a spring-loaded system is shown.

[0068] Figure 13 A first example of a mechanical valve is shown;

[0069] Figure 14 A cross-section of a second example of a mechanical valve is shown;

[0070] Figure 15 A second example of a mechanical valve is shown;

[0071] Figure 16 A flowchart illustrating how to determine if the nozzle is on the occlusal surface of the teeth is shown.

[0072] Figure 17 A flowchart illustrating how to operate the oral irrigation system is shown;

[0073] Figure 18 A combined toothbrush and oral irrigation system that operates on the side of the teeth is shown;

[0074] Figure 19 A combined toothbrush and oral rinsing system that operates on the occlusal surface of teeth is shown;

[0075] Figure 20 A three-dimensional point diagram showing the nozzle contacting the teeth during brushing is shown; and

[0076] Figure 21 A three-dimensional dot plot of the nozzle 104 in contact with the teeth during brushing is shown. Detailed Implementation

[0077] The invention will be described with reference to the accompanying drawings.

[0078] It should be understood that while the detailed description and specific examples indicate exemplary embodiments of the apparatus, system, and method, they are 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, system, and method of the present invention will become more readily apparent from the following description, the appended claims, and the accompanying drawings. It should be understood that the drawings are merely schematic and not drawn to scale. It should also be understood that the same reference numerals are used in all the drawings to denote the same or similar parts.

[0079] This invention provides a system for oral irrigation. The system includes a fluid delivery tube having a proximal end and a distal end. The proximal end is used to receive oral irrigation fluid. A nozzle is disposed at the distal end of the fluid delivery tube. The system also includes an interdental sensor for detecting whether the nozzle is in the interdental space and a motion sensor for measuring nozzle displacement. The processor is configured to determine whether the nozzle is moving along the occlusal surface of a tooth based on the nozzle displacement being greater than a critical distance and the interdental sensor not detecting interdental space during the nozzle displacement, wherein the critical distance indicates the length of the tooth.

[0080] Figure 1 A schematic diagram of the head section 106 of a toothbrush is shown. A fluid delivery tube 102 with a nozzle 104 at the distal end is attached to the toothbrush head 106. The nozzle 102 extends from the head 106 in the same (or substantially the same) direction as the bristles 108 of the toothbrush.

[0081] The fluid delivery tube 102 and nozzle 104 can be used for oral floss cleaning. Figure 1 A combined dental floss cleaning and brushing system is shown. The proximal end of the fluid delivery tube 102 can be connected to a pump and fluid reservoir for dental floss cleaning. Additionally, a pressure sensor can be connected to the fluid delivery tube to measure the pressure inside the fluid delivery tube.

[0082] Figure 2 A schematic diagram of a toothbrush with an oral irrigator is shown. The toothbrush includes a fluid delivery tube 102 with a nozzle 104 at its distal end, a pump 202 connected to the fluid delivery tube 102, a fluid reservoir 204 storing the fluid to be pumped, and a sensor 206 for measuring the pressure and / or flow rate inside the fluid delivery tube 102. The toothbrush also has a head section 106 that houses the toothbrush bristles 108 and the nozzle 102 of the fluid delivery tube 102.

[0083] In this example, the fluid reservoir 204, pump 202, and sensor 206 are part of the toothbrush. However, these components can be separate from the toothbrush and connected via the fluid delivery tube 102. Additionally, the fluid delivery tube 102 and nozzle 104 can be independent (not part of the toothbrush) and form part of an oral rinsing system.

[0084] Additionally, in this example, sensor 206 will be described as a pressure sensor. However, sensor 206 could also be a flow sensor or a combined sensor capable of measuring the flow rate and pressure inside the fluid delivery pipe.

[0085] When brushing teeth or rinsing the mouth, the pressure drop in the fluid delivery line 102 can be used to indicate that the nozzle 104 has reached the interdental space. Figure 2In the example, the oral rinsing system is a component of a combined brushing and flossing toothbrush. The components of the oral rinsing system include a fluid delivery tube 102 having a nozzle 104 at its distal end and an orifice at the nozzle 104. When the oral rinsing system is a component of a combined brushing and flossing toothbrush as shown, the orifice of the nozzle 104 may be near the bristles 108 of the toothbrush.

[0086] Pump 202 is used to drive fluid from fluid reservoir 204 through fluid delivery pipe 102. Pressure sensor 206 is used to directly or indirectly determine the fluid flow rate and / or fluid pressure through fluid delivery pipe 102.

[0087] Pressure sensor 206 is used to sense a pressure drop to indicate interdental space. For example, nozzle 104 may have a conformable orifice at the point of contact with the tooth. When in contact with the hard surface of the tooth, the conformable nature of nozzle 104 allows fluid flow to be substantially blocked. This substantial blockage results in an increase in pressure in fluid delivery line 102, which can be registered in pressure sensor 206. Alternatively, nozzle 104 may be used with a mechanically modified orifice (e.g., spring-loaded) that opens only by disrupting contact with a hard surface (e.g., leaving a hard tooth in the interdental space).

[0088] The fluid used to sense the interdental space can be a liquid. For example, the liquid used for sensing can be the same liquid used for spraying, flossing, and / or rinsing the mouth. A pressure drop in the fluid delivery line 102 can then trigger an interdental cleaning process, such as involving an increase in flow rate.

[0089] The fluid delivery tube 102 can be used for both interdental cleaning and sensing of pressure drop. A low flow rate of fluid can be used during interdental space detection, and then a high flow rate can be used for the interdental cleaning process. In this way, the fluid is used more efficiently, and the user does not have to deal with excess liquid in their mouth.

[0090] When in contact with teeth, the combination of pressure sensor 206 and (at least) partially blocked nozzle 104 allows for robust and reliable detection of interdental spaces. These functions can be integrated into brush heads or devices with dental floss cleaning capabilities. The dental floss cleaning function can be selectively activated at interdental spaces (i.e., when interdental spaces are detected), thereby conserving floss cleaning fluid and preventing ineffective floss cleaning outside the interdental spaces.

[0091] In this example, there is only one fluid reservoir 204, and the fluid used to detect the interdental space is the same as the fluid used for oral rinsing / flossing. However, a first fluid for detecting the interdental space and a second fluid for cleaning the interdental space can be used. There can also be a first fluid reservoir for the first fluid and a second fluid reservoir for the second fluid.

[0092] Figure 3 A schematic diagram of a toothbrush with an oral irrigator and an air inlet 302 is shown. The toothbrush has an air inlet 302 and a switch 304 between a fluid reservoir 204 and the air inlet 302. The switch 304 is configured to allow a pump 202 to pump air or fluid through a fluid delivery tube 102. Alternatively, a second fluid reservoir with air (or any gas) may be used instead of the air inlet 302. One or more air inlets 302 may also be used to ensure that the pump 202 can still pump air if any air inlet 302 is blocked by the user's hand.

[0093] Pump 202 provides airflow through fluid delivery pipe 102 and nozzle 104 for detecting interdental spaces and provides a burst or flow of liquid for interdental cleaning. In this way, the sprayed liquid is used more efficiently. Therefore, a combination of airflow for identifying the interdental area and liquid flow for performing interdental cleaning is used. This prevents unwanted cleaning fluid from being lost into the user's mouth. In this example, pump 202 is modified to sequentially pump gas or liquid using switch 304 between liquid reservoir 204 and a gas source (e.g., a second reservoir or air inlet 302).

[0094] The controller can be used to control pump 202 to pump a first fluid (e.g., air) when pressure sensor 206 does not detect a decrease in pressure in fluid delivery line 102 (i.e., nozzle 104 is in contact with teeth), and to pump a second fluid (e.g., cleaning fluid) when pressure sensor 206 detects a decrease in pressure in fluid delivery line 102 (i.e., nozzle is in interdental space).

[0095] Figure 4 The first example of the nozzle 104 design is shown. Figure 4 a) This shows the nozzle 104 when it is in the interdental space and the orifice of the nozzle 104 is open. Figure 4 b) shows the nozzle 104 when it is in contact with the tooth 602 and the orifice of the nozzle 104 is closed or partially closed.

[0096] In this example, the tip of nozzle 104 is made of conformal material 604. Material 604 has the property that when nozzle 104 comes into contact with a hard surface (e.g., teeth 602), material 604 partially flattens against the hard surface, thus substantially blocking the orifice of nozzle 104 on the hard surface of teeth 602. Suitable conformal material 604 is a soft, elastic material, such as silicone, rubber, etc. This substantial blockage results in an increase in pressure within fluid delivery conduit 102, which can be registered by pressure sensor 206.

[0097] In this example, the orifice of nozzle 104 will remain open even when nozzle 104 is not in contact with the user's teeth 602. For example, at the beginning or end of brushing / flossing, or when nozzle 104 moves from the upper jaw to the lower jaw, for example, nozzle 104 will not be in contact with the user's teeth 602. For this reason, there is a risk that cleaning fluid may undesirably be sprayed into the mouth when nozzle 104 loses contact with teeth 602. To reduce this effect, the fluid flow rate during interdental sensing can be much lower than the fluid flow rate used during the cleaning process.

[0098] Furthermore, it may be advantageous to initiate the cleaning cycle only after the pressure sensor 206 senses a pressure drop (rather than just low pressure). In this way, unwanted release of cleaning fluid can be avoided before the nozzle contacts the teeth 602.

[0099] When the conformal material 604 disengages from the tooth 602 (e.g., enters the interdental space), the nozzle 104 is unblocked, the pressure drops rapidly, and the pressure sensor 206 interprets the nozzle 104 as part of the interdental space. At this point, an interdental cleaning cycle can be initiated, which may include a relatively high flow rate of cleaning fluid or a series of cleaning fluid bursts. The duration of the interdental cleaning cycle can be a (fixed) short time to avoid unwanted fluid release. As the nozzle 104 moves to the next tooth 602, the pressure in the fluid delivery tube 102 will increase rapidly, which can be interpreted as the nozzle 104 leaving the interdental space, thus allowing the cleaning cycle to be stopped if it is not yet complete. In this way, the pressure sensor 206 can also ensure that if the nozzle 104 traverses the interdental space faster than required to implement a fixed cleaning cycle, the cycle can be terminated prematurely to conserve cleaning fluid.

[0100] For example, once the pressure has increased (rapidly), the pressure sensor can return to a "sensing mode" (e.g., using a first fluid at a lower flow rate to sense the interdental space) and remain in that mode until entering the subsequent interdental space.

[0101] It should be noted that these system configurations (with different flow rates, detection pressure drops, and the ability to stop the cleaning cycle if the nozzle moves too early from the interdental space) can be applied to each of the nozzle designs described below.

[0102] Figure 5 A second example of the nozzle 104 design is shown. Figure 5 a) shows the nozzle 104 when the orifice of the nozzle 104 is open. Figure 5 b) shows the nozzle 104 when the orifice of the nozzle 104 is closed or partially closed.

[0103] In this example, nozzle 104 includes a mechanically modified (spring-loaded) orifice. This orifice includes a spherical stop 702, spring-loaded by spring 704, to be in an open position when not in contact with a hard surface (e.g., no force is applied to the stop 702). The orifice has the characteristic that when nozzle 104 contacts a hard surface (e.g., tooth 602), the stop 702 is pushed against the orifice of nozzle 104, thus substantially blocking the orifice when pressed against the hard surface of tooth 602. This substantial blockage results in an increase in pressure within fluid delivery line 102, which can be detected by pressure sensor 206 in the same manner as described above.

[0104] The stop 702 can also be designed to deflect the cleaning fluid from its normal direction (aligned with the axis of the tube). This is advantageous for guiding the fluid to more of the interdental surface of the tooth 602. The spring 704 can also be configured such that the opening and / or closing of the stop 702 is achieved relatively slowly (e.g., for about half the residence time of the nozzle 104 in the interdental region). In this way, the cleaning fluid will be sprayed more in the lateral direction first, and then more guided in the axial direction of the nozzle 104 when the stop 702 is fully open. In this way, the cleaning fluid will be dynamically sprayed first into the shallower region of the interdental space, and then into the deeper portion. Thus, the stop can serve as both a valve closing element and a flow guiding element, such that the flow varies according to the valve state between fully open and fully closed.

[0105] The orifice of the nozzle 104 can be designed to fully close the teeth 602 when the brush is held at a 45-degree angle or greater relative to the plane of the teeth 602.

[0106] For example, the nozzle 104 may need to be slightly longer than the toothbrush bristles (in the combined oral irrigator and toothbrush assembly) so that it still contacts the teeth 602 when angled, and the nozzle 104 includes a flexible tube that remains comfortable when the toothbrush / nozzle 104 is at a 90° angle. For example, longer than Figure 5 The larger ball shown can accommodate more angles.

[0107] It is understandable that different designs can be used to block fluid flow when in contact with tooth 602 (sensing high pressure) and to release fluid flow when not in contact (i.e., in the interdental space).

[0108] Figure 6 A third example of the nozzle 104 design is shown. Figure 6 a) shows the nozzle 104 when it is in the interdental space and the orifice of the nozzle 104 is open. Figure 6 b) shows the nozzle 104 when it is in contact with the tooth 602 and the orifice of the nozzle 104 is closed or partially closed.

[0109] In this example, nozzle 104 has a kink 802 that closes / restricts fluid flow through nozzle 104 when in contact with tooth 602. When nozzle 104 is forced against tooth 602, the force from tooth 602 causes kink 802 to bend inward, thereby reducing the orifice area of ​​nozzle 104 and restricting fluid flow from nozzle 104. This increases the pressure inside fluid delivery tube 102, which can be measured by pressure sensor 206 connected to fluid delivery tube 102.

[0110] Figure 7 A fourth example of the nozzle 104 design is shown. Figure 7 a) This shows the nozzle 104 when it is in the interdental space and the orifice of the nozzle 104 is open. Figure 7 b) shows the nozzle 104 when it is in contact with the tooth 602 and the orifice of the nozzle 104 is closed or partially closed.

[0111] In this example, the nozzle 104 has a flexible, flat, duckbill-shaped orifice. When on the teeth 602, the two legs 902 push the orifice closed, but when the legs 902 can bend, the orifice opens between the teeth 602 (in the interdental space). The advantage of this design is that the orifice of the nozzle 104 can extend from the teeth 602 to have more space for the fluid jet to form for interdental cleaning.

[0112] Figure 8 The fifth example of the nozzle 104 design is shown. Figure 8 a) This shows the nozzle 104 when it is in the interdental space and the orifice of the nozzle 104 is open. Figure 8 b) shows the nozzle 104 when it is in contact with the tooth 602 and the orifice of the nozzle 104 is closed or partially closed.

[0113] In this example, a spherical stop 1002 is placed in the orifice of the nozzle 104. Within the interdental space, the stop 1002 is pushed open by the pressure of the fluid flow. When the stop 1002 contacts the teeth 602, the teeth 602 prevent the stop 1002 from being pushed open, thus reducing the flow of fluid. The stop 1002 can be attached to the nozzle 104 by a retaining mechanism (e.g., a rope, spring, etc.).

[0114] Figure 9 A nozzle 104 with a mechanical valve 1102 in different states is shown. Four nozzles 104a, 104b, 104c, and 104d are shown. The first nozzle 104a is in contact with a single tooth 602, so only one force is applied to it (from the tooth). The second nozzle 104b is located in the interdental space, so it has two forces applied to it (on each side of the interdental space, from two adjacent teeth). The third nozzle 104c is in the air and is not in contact with any tooth 602, so no force is applied to it. The fourth nozzle 104d is in contact with a tooth 602 at an angle and has one force from the tooth 602 depending on that angle.

[0115] Dental flossing devices are typically effective only in the interdental space. Flossing outside the interdental space has limited effectiveness and can lead to spillage of the flossing fluid and undesirable distribution of liquids in the mouth. This is particularly problematic for combination devices that integrate flossing and brushing functions, as an unrestricted design is desired for easy operation of the combination device, and the device size is limited, leaving only a limited space for the fluid reservoir. Additionally, the fluid can dilute the fluoride in toothpaste, potentially reducing the effectiveness of fluoride in protecting against cavities.

[0116] This example utilizes the anatomical differences in the interdental space, where two adjacent teeth 602 form a narrowed channel. A mechanical valve 1102 closes the orifice of the nozzle 104 at the normal peak pressure of the interdental cleaning jet. This could be, for example, a high-crack pressure duckbill valve. This means that automatic fluid flow is prevented when the nozzle is in free space or against a tooth. Therefore, the interdental space geometry is designed to open a valve that would otherwise be closed, rather than to close a valve that would otherwise be opened (as in the example above).

[0117] When the mechanical valve 1102 is pushed into the interdental space, two opposing teeth 602 press against two opposing sides, releasing the mechanical valve and opening the orifice of the nozzle 104 at the peak injection pressure. Additionally, a controller can be used to record when the mechanical valve 1102 opens and closes based on the characteristics of the pump 202. For example, when an open state is detected, the peak pressure can be increased. This allows for low-pressure and low-force closure of the mechanical valve 1102, which is generally more robust.

[0118] This example allows for a low-cost mechanical valve 1102 design that opens the orifice of nozzle 104 only when the mechanical valve 1102 is pushed into the interdental space anatomy. This allows the interdental cleaning jet to be sprayed only into the interdental space, thus with no (or minimal) fluid overflow.

[0119] In some examples, the mechanical valve 1102 closes the orifice of the nozzle 104 at all times except when forces are applied from both sides (i.e., when in contact with the two opposing tooth surfaces of the interdental space). The mechanical valve 1102 will not open if it is not in contact with the tooth 602 (e.g., in air) or if only one side of the mechanical valve 1102 contacts the tooth 602. In some other examples, the mechanical valve opens only due to two opposing radial forces (from the opposing teeth 602).

[0120] For example, nozzle 104a (in) Figure 9 In the first example, there will be only one force from a single tooth 602, so the mechanical valve 1102 will not open and there will be no cleaning fluid jet. However, the nozzle 104b is located in the interdental space and is therefore in contact with two adjacent teeth. This causes each of the two teeth to exert a force on the mechanical valve 1102. Due to the presence of two forces from the adjacent teeth, the mechanical valve 1102 opens, and a cleaning fluid jet can be allowed through the mechanical valve 1102 to pass through the nozzle 104b to clean the interdental space. In this example, the force exerted by the tooth 602 has a lateral component relative to the nozzle 104b. In some examples, the mechanical valve 1102 can be configured to open only when two lateral forces (force components) are applied to the mechanical valve 1102 on opposite sides of the mechanical valve 1102 (through the adjacent teeth in the interdental space).

[0121] Nozzle 104c is in the air and therefore does not have any force exerted by the teeth 602, so mechanical valve 1102 remains closed. Nozzle 104d has a force exerted on it by a single tooth 602, which has a lateral component (relative to nozzle 104d). However, since there is only one force, mechanical valve 1102 will not open for nozzle 104d.

[0122] Figure 10 The force balance on mechanical valve 1102 is shown in a simplified schematic diagram. Figure 10 a) shows a cross-section of the mechanical valve 1102 on the nozzle 104. Figure 10 b) shows a top view of the mechanical valve 1102. Figure 10 The image shows a duckbill-shaped valve, however Figure 10 The force balance shown applies to other examples of mechanical valve 1102.

[0123] A general characteristic of the mechanical valve 1102 is its burst pressure (CP), which is the pressure at which the mechanical valve 1102 opens due to the fluid force becoming greater than its closing strength. In some examples, the CP of the mechanical valve 1102 is higher than the peak pressure in the nozzle 104 to keep the mechanical valve 1102 closed when in normal contact with the teeth 602 or only in contact with one side. The mechanical valve 1102 is designed to reduce CP when both sides are in contact with the teeth 602 in the interdental space and due to the normal force of the user pressing the oral irrigator against the teeth 602. Thus, the mechanical valve 1102 opens at the peak pressure to release a cleaning burst.

[0124] Interdental cleaning may require a liquid velocity of 25 m / s to 50 m / s (approximately 3 bar to 13 bar (300 kPa to 1.3 MPa) liquid pressure). The typical maximum pressure for oral irrigators is 7 bar (700 kPa). A typical nozzle with an orifice area of ​​104 mm² can reach 0.25 mm². 2 up to 0.8mm 2 Within this range, the typical value is 0.5mm. 2 The force required for a mechanical valve 1102 of this size at 7 bar (700 kPa) would be 0.35 N. To securely keep the valve closed, a closing force of 0.4 N can be selected for the mechanical valve 1102. To securely open it at the interdental space, this force needs to be reduced to, for example, 0.3 N, thus using a force of 0.1 N operating in the negative direction. Typical normal force during brushing can be as high as 2.5 N. This force will be split between the bristles 108 and the nozzle 104, but by using appropriate mechanical design, 0.1 N of this force can be directed into the opening force of the mechanical valve 1102.

[0125] exist Figure 10 In this configuration, the pressure in nozzle 104 will use a pressure-driven force Fp 1204 to open mechanical valve 1102, while a valve-closing mechanism will use a closing force Fc 1206 to push mechanical valve 1102 in the opposite direction. Mechanical valve 1102 can be designed such that Fc = Fp (mechanical valve 1102 remains closed), but the closing force Fc 1206 decreases when both sides of nozzle 104 receive a pressing force 1208 generated by nozzle 104 being pushed into the interdental space by two adjacent teeth. The pressing force 1208 from the two adjacent teeth can be perpendicular to and / or parallel to the direction of the nozzle. In this example, the pressing force 1208 is shown as perpendicular to the direction of nozzle 104; however, in some examples, the pressing force 1208 can be (partially) parallel to the direction of nozzle 104.

[0126] The total pressure driving force Fp = P × A can be calculated from the pressure P of the internal nozzle 104, where A is the area of ​​the mechanical valve 1102 (in this example, it is similar to the orifice area of ​​the nozzle 104). A pressure of 7 bar (700 kPa) is applied to 0.5 mm. 2 Mechanical valve 1102 has a total force of 0.35N.

[0127] In one example, the pressure behind nozzle 104 can be constant when nozzle 104 is closed. For example, pump 202 can pump the cleaning fluid into a hydraulic accumulator to maintain the pressure at, for example, 7 bar (700 kPa). When mechanical valve 1102 opens, a single burst of liquid can be sprayed, reducing the pressure at which nozzle 104 is subsequently closed. This oral irrigator can efficiently utilize both the cleaning fluid and power because the cleaning fluid always flows out at a high speed, without wasting energy, and the fluid is sprayed at a low speed, which does not remove biofilm. Alternatively, the oral irrigator can also be driven by a more standard pulsed irrigation pump. This can be used to deliver multiple bursts while nozzle 104 remains in the interdental space.

[0128] Examples with hydraulic accumulators can also be ignited multiple times, depending on the rate at which the accumulator is refilled after each burst. Pulsating pumps can use more energy, depending on whether the pump continues pumping when mechanical valve 1102 is closed. The controller can also be used to shut off or reduce the pumping power of pump 202 when no volumetric flow or pressure release is sensed at nozzle 104.

[0129] Figure 11 The brush head 106 of the combined brushing and flossing device in use is shown. All interdental spaces have a narrowing gap that generates lateral forces on an elongated body (i.e., nozzle 104) narrow enough to fit within the interdental spaces. To accommodate different gap sizes, the tip of the nozzle 104, which interacts with two opposing teeth, can be designed in a wedge shape. The wedge-shaped nozzle 104 can preferably accommodate a larger interdental space. When the user presses the device against the teeth 602, the nozzle 104 may need to protrude sufficiently beyond the bristles to withstand the contact forces with the sides of the interdental spaces.

[0130] Figure 12 A brush head 106 of a combined brushing and flossing device with a spring-loaded system 1402 is shown. In the combined toothbrush and oral irrigator, the nozzle 104 should protrude sufficiently so that it will be pushed into the interdental space, but not so much that it will obstruct brushing. In this example, using a spring or other resiliently controlled connection 1402 between the brush head 106 and the nozzle 104, the nozzle 104 can be independently moved in and out of the plane of the brush head 106. This method also makes the thrust of the mechanical valve 1102 less dependent on the user's brushing force.

[0131] In this example, nozzle 104 can be moved in and out of the brushing area using a spring-loaded system 1402. This has the advantage that the mechanical valve 1102 can be designed to have sufficient force in the interdental space to open the orifice of nozzle 104, and thus reduces the risk of nozzle 104 obstructing brushing when it is on other surfaces.

[0132] However, it is also possible to have a nozzle 104 with approximately the same length as the bristles 108, since the bristles 108 are typically flexible enough to conform to the contours of the teeth. In typical toothbrush designs, there are different bristle lengths to accommodate all anatomical structures.

[0133] As described above, the valve configuration can also be used as an inter-tooth sensor. The fluid pressure in the fluid delivery line 102 can then be low, thus allowing the mechanical valve 1102 to have a low burst pressure. Therefore, a smaller pressing force 1208 from both sides of the inter-tooth space is required. This allows the mechanical valve 1102 to be more robust and allows for more lenient design specifications.

[0134] When mechanical valve 1102 is normally closed, the inter-tooth sensor function will not sense a decrease in flow or pressure until mechanical valve 1102 is opened. For example, this sensing could be based on a measurement of power consumption or current drawn by the pump, or it could be based on a flow or pressure measurement.

[0135] For example, once the mechanical valve 1102 opens in the inter-tooth space, an increase in flow rate or a decrease in pressure in the fluid delivery line 102 can be detected, for example, by a pressure sensor. The controller can respond by providing one or more bursts of cleaning fluid, for example, by increasing the power of the pump 202.

[0136] Therefore, when the nozzle 104 is not in contact with the teeth 602, or when the nozzle 104 is in contact with the teeth 602 but not in the interdental space, the mechanical valve 1102 allows the oral irrigator to be unused and thus does not waste cleaning fluid.

[0137] When power consumption is used as a sensing input, the pump may not completely shut off. Depending on the type of pump, it may also operate at a low speed. For example, sensing mode would require maintaining a certain level of pressure upstream of the valve while keeping it closed.

[0138] Figure 13 and Figure 14 References are shown Figure 10 The first example of a general type of mechanical valve 1102 is discussed. Figure 13 A possible design for the mechanical valve 1102 is shown. Figure 14 a) shows a cross-section of the mechanical valve 1102 in the inter-tooth space, wherein the mechanical valve 1102 is open. Figure 14b) shows a cross-section of the mechanical valve 1102 in contact with the tooth 602, wherein the mechanical valve 1102 is closed.

[0139] A mechanical valve 1102 design requiring only a single component can be a resilient duckbill valve. If properly sized, the duckbill valve will be pushed open by the two opposing tooth surfaces in the interdental space. Typically, duckbill valves are used to achieve mechanical valves 1102 with low burst pressure. However, in some examples, high burst pressure valves need to be designed to withstand fluid pressure when not pressed into the interdental space. The burst pressure of a duckbill design can be increased by using a rigid elastomer or a relatively thick valve design. A properly designed duckbill valve will not open at the peak pressure of the cleaning fluid, but rather at a combination of sufficient internal peak pressure and the bilateral pressure 1208 at the interdental space location.

[0140] Figure 15 A second example of mechanical valve 1102 is shown. This alternative design of mechanical valve 1102 mechanically clamps the resilient nozzle 104 and the spring-loaded clamp 1702. Clamp 1702 opens when pushed into the inter-tooth space because of the compressive force that overcomes the spring bias of the clamp. Figure 15 a) shows lever 1704 being pushed together at its distal end, which opens the nozzle at the opposite proximal end. Figure 15 b) illustrates a lever that opens via spring bias when the distal end is no longer clamped in the interdental space. The lever can also be in a different plane from the cleaning fluid jet so as not to obstruct the cleaning flow. This is merely one example of a pivot or oscillating lever design that converts compression at the distal end into nozzle opening at the proximal end.

[0141] A drawback of the aforementioned mechanical valve 1102 design is that the opening size of the nozzle 104 may depend on the force with which the nozzle 104 is pushed within the interdental space and the specific anatomy of the interdental space (distance, etc.). Using a spring-loaded tip can provide more control over this, but another solution for generating the opening size is a dual-modal system, which depends less on the lateral pressures 1208 (from the two teeth in the interdental space) and the intensity of the displacement. An example of a dual-modal system is a clicker, which is a leaf spring with preloaded tension deformation.

[0142] In this system, there are two preferred states (i.e., open and closed). If force is applied, the system quickly clicks to the second preferred state, and if the force is released, the system clicks back. This spring-operated system can be designed to open the mechanical valve 1102 to a predetermined size when the nozzle 104 is pushed into the interdental space.

[0143] Depending on whether the nozzle is on the tooth surface or in the interdental space, the examples above provide different system operation functions. Therefore, these systems are able to sense whether the nozzle is positioned on the tooth surface or in the interdental space.

[0144] In some systems, it is also desirable to be able to distinguish between the location of the cleaning device on the occlusal (teeth-biting) surface and the lateral surface. For example, different cleaning parameters are applied to the lateral surface (because these are closer to the more sensitive gingival line) and the occlusal surface. There is no interdental space on the occlusal surface.

[0145] On the other hand, sensing based on the interdental space, such as using any of the methods described above (i.e., a system with an open flow path when the nozzle is in the interdental space, or a system with a closed flow path when the nozzle is on the tooth surface), is used to detect the occlusal surface. Any other known devices for sensing the interdental space may also be used in conjunction with the methods described below.

[0146] Figure 16 A flowchart is shown showing how to determine whether the nozzle 104 is on the occlusal surface of the tooth 602.

[0147] This method utilizes the detection of inter-tooth space and the monitoring of nozzle movement. Therefore, in addition to the aforementioned components, a motion sensor for measuring nozzle displacement is also provided.

[0148] In step 1802, the distance traveled by the nozzle is monitored by a motion sensor. It is determined when this distance exceeds a critical distance. Taking into account different tooth sizes, the critical distance is based on the size of a typical tooth. For example, the critical distance could be the minimum tooth length (e.g., 1 cm), or it could be tailored to the user taking into account the tooth's size or minimum size. In step 1804, the interdental space is detected during nozzle movement (i.e., it is determined that the nozzle is already in the interdental space).

[0149] If the distance traveled by the nozzle is greater than the critical distance (step 1802) and no interdental space has been detected (step 1804), then the nozzle can be determined to be on the occlusal surface of the tooth (step 1806).

[0150] Alternatively, if the distance traveled by the nozzle is greater than the critical distance (step 1802) but interdental space is detected (step 1804), then the nozzle can be determined to be on the side of the tooth (step 1808).

[0151] Testing the occlusal surfaces, for example, confirms that the toothbrush is not close to the interdental spaces, and therefore not close to the gum line. This means that different flow conditions can be applied. Similarly, different brushing conditions are suitable for different areas of the teeth.

[0152] Figure 17A flowchart illustrating how to operate the oral irrigation system is shown. At the start of oral irrigation, the oral irrigation jet may be inactive (step 1902). Three conditions must be met for oral irrigation to begin: the nozzle of the oral irrigation system must be in contact with the teeth (detected in step 1904), the distance traveled must be greater than a critical distance (determined in step 1802), and the interdental space must be detected or not detected (1804).

[0153] If no interdental space is detected, in step 1806 the nozzle can be determined to be on the occlusal surface, and oral irrigation with an occlusal spray pattern can be initiated on the occlusal surface. If interdental space is detected, in step 1808 the nozzle can be determined to be on the lateral surface of the tooth, and oral irrigation can be initiated on the lateral surface of the tooth with a spray pattern for the lateral surface. Oral irrigation can occur for a predetermined amount of time, after which the oral irrigator stops spraying (in step 1906) and continues to sense three conditions.

[0154] Oral irrigation may differ for the occlusal surface and the lateral surfaces of teeth. Additionally, oral irrigation can be integrated into a combined toothbrush and oral irrigation system.

[0155] For example, when the brush is near the gum line, it is not preferable to brush vigorously or deliver large amounts of fluid, such as fluoride for remineralization or bicarbonate for whitening. For instance, when the toothbrush is in interdental mode or near the gum line, it is preferable to brush softly and deliver fluid for interdental or pocket cleaning; however, when the toothbrush is on the occlusal surfaces, brushing can be more forceful, and a larger amount of fluoride can be delivered to remineralize the teeth (or the spray can be interrupted to avoid excessive fluid volume buildup in the mouth). Therefore, oral rinsing and brushing operating parameters (e.g., brushing speed or force) can vary based on testing.

[0156] This method continuously monitors contact and interdental space, allowing it to detect the transition from the occlusal surface to the lateral surface and vice versa.

[0157] Any interdental sensor can be used as part of this method to sense the occlusal surfaces of teeth. Interdental sensing can be based on flow or pressure sensors in a fluid delivery tube as described above, or on electrical sensors such as resistive sensors in or on the fluid delivery tube. Typically, changes in sensor signal characteristics over brushing distance can be used to distinguish between the interdental and occlusal sides.

[0158] Motion sensors used to detect nozzle movement may already exist in some toothbrushes. These can include accelerometers and / or gyroscopes. As mentioned above, interdental sensors can function as both contact sensors and sensors for interdental space. As described above, measurements are taken to determine that the brush has moved at least the distance between two teeth (>1 cm), but no interdental space is detected. Other measurements can be taken to determine that the brush is in contact with the teeth, so the brush is not merely in the air.

[0159] Figure 18 A combined toothbrush and oral rinsing system that operates on the side of the teeth is shown. Figure 18 a) A brush head is shown having a fluid delivery tube 102, a nozzle 104, a neighbor sensor 2002, and a motion sensor 2004. In this example, the neighbor sensor 2002 may be a pressure sensor. Figure 18 b) shows the corresponding Figure 18 A graph showing the pressure versus distance for the tooth arrangement 602 in a). The pressure signal can be determined from the pressure sensor 2002, and the distance can be determined from the motion sensor 2004. The graph shows the pressure signal 2006 decreasing in the interproximal space. For comparison, pressure signal 2008 is shown, corresponding to a brush in air (no pressure difference).

[0160] Figure 19 A combined toothbrush and oral rinsing system that operates on the occlusal surface of teeth is shown. Similar to... Figure 18 , Figure 19 a) A brush head is shown having a fluid delivery tube 102, a nozzle 104, a neighbor sensor 2002 (a pressure sensor in this example) and a motion sensor 2004. Figure 19 b) shows the corresponding Figure 19 A graph showing the pressure versus distance for the arrangement of teeth 602 in diagram a). In this graph, pressure signal 2006 shows no change (or minimal change) because there is no interdental space in the occlusal surface of tooth 602. For comparison, pressure signal 2008 is shown, corresponding to a brush in air (no pressure difference). Although both signals 2008 and 2006 show no (or minimal) change, the pressure signal on the occlusal surface of tooth 2006 exceeds the pressure signal of the brush in air 2006. In this way, it can be determined whether the sensor is on the occlusal surface of the tooth.

[0161] Alternatively, the flow sensor can be used as a neighbor sensor 2002. Other sensor types can also be used alternatively.

[0162] By using an interdental sensor 2002 that senses changes in the flow rate or pressure of the fluid in the fluid delivery tube 102, the same system as that used for interdental space detection, can determine that the combined toothbrush and oral irrigator are located on the occlusal surface of the teeth 602. When brushing, the nozzle 104 contacts the teeth 602, wherein the contact with the teeth 602 is broken when the nozzle 104 reaches the interdental space. When the tooth contact is broken, the pressure inside the fluid delivery tube 102 decreases, and the flow rate increases.

[0163] like Figure 17 As shown, the device's controller can be configured to activate different brushing or spraying modes based on whether the nozzle 104 (and the brush) is on the occlusal surface or the lateral surface of the teeth. For example, the combined toothbrush and oral rinsing system may have a motor to operate the toothbrush head for brushing. The motor can then be operated differently based on a processor that detects whether the brush is on the occlusal surface or the lateral surface of the teeth. Similarly, different spraying modes of the oral rinsing system can also be used on both the occlusal and lateral surfaces of the teeth.

[0164] As described above, interdental sensing can be based on any suitable sensing mode. For example, the resistance change between two electrodes can be sensed at nozzle 104. Nozzle 104 will move along the teeth, contact the teeth, and when nozzle 104 reaches the interdental space, nozzle 104 will be captured between the two teeth. The resistance between the electrodes can then be monitored. When the electrodes contact, for example when the two electrodes are brought together by compression in the interdental space, the resistance will decrease.

[0165] Combinations of sensor signals can be used to enhance the characteristics of occlusal and interdental sensing. This can be achieved by using additional sensor signals (e.g., brushing force, angle) and appropriate algorithms that interpret the combination of sensor measurements to determine if the brush is brushing the occlusal surfaces. For example, force sensors can be used to detect force distribution (based on bending in response to pressure) or to detect brushing angle information (rolling, occlusal, pitch).

[0166] Figure 20 A three-dimensional point map showing the contact between the nozzle 104 and the teeth during brushing is presented. It demonstrates that position monitoring can determine position with sufficient accuracy to distinguish between tooth position and interdental space position.

[0167] Figure 21 A two-dimensional dot diagram showing the contact between the nozzle 104 and the teeth during brushing is shown. Figure 21Circle 2302 in the diagram represents the coordinates assigned to the interdental space. A machine learning training session can be performed to teach the processor to distinguish interdental, occlusal, and airborne fluid pressure and resistance signal characteristics relative to angular combinations and / or interdental position coordinates. Once the angular combinations and / or (3D) coordinates of the interdental space are determined through the training session, this information can be stored in memory and used by the processor in future cleaning sessions.

[0168] Those skilled in the art can readily develop controllers and / or processors for performing any of the methods described herein. Therefore, each step of the flowchart can represent a different action performed by the controller and / or processor, and can be performed by a corresponding module of the controller and / or processor.

[0169] As described above, the embodiments utilize a controller. The controller can be implemented in various ways, using software and / or hardware, to perform a variety of desired functions. A processor is one example of a controller employing one or more microprocessors, which can be programmed using software (e.g., microcode) to perform the desired functions. However, the controller can be implemented with or without a processor, and can also be implemented as a combination of dedicated hardware performing certain functions and processors (e.g., one or more programmable microprocessors and associated circuitry) performing other functions.

[0170] Examples of controller components that may be employed in various embodiments of this disclosure include, but are not limited to, conventional microprocessors, application-specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs).

[0171] In various implementations, a processor or controller may be associated with one or more storage media, such as volatile and non-volatile computer memories (e.g., RAM, PROM, EPROM, and EEPROM). The storage media may be encoded with one or more programs that, when executed on one or more processors and / or controllers, perform the required functions. The various storage media may be fixed within the processor or controller, or may be transferable, allowing one or more programs stored thereon to be loaded into the processor or controller.

[0172] By studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand and implement 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 articles "a" or "an" do not exclude a plurality. No reference numerals in the claims should be construed as limiting the scope. If the term "suitable" is used in the claims or description, it should be noted that the term "suitable" is intended to be equivalent to the term "configured as."

Claims

1. A system for oral irrigation, comprising: A fluid delivery tube (102) having a proximal end and a distal end, wherein the proximal end is used to receive oral irrigation fluid; The nozzle (104) is located at the distal end of the fluid delivery pipe (102); An interdental sensor (2002) is used to detect whether the nozzle (104) is in the interdental space; A motion sensor (2004) is used to measure the displacement of the nozzle (104); as well as The processor is configured to determine that the nozzle (104) is moving along the occlusal surface of the tooth based on the displacement of the nozzle (104) being greater than a critical distance and the interdental sensor (2002) not detecting interdental space during the displacement of the nozzle (104), wherein the critical distance indicates the length of the tooth.

2. The system of claim 1, wherein the processor is further configured to determine that the nozzle (104) is moving along the side of the tooth based on the displacement of the nozzle (104) being greater than the critical distance and the interdental sensor (2002) detecting interdental space during the displacement of the nozzle (104).

3. The system of claim 2, further comprising a pump (202) and a controller, the pump being configured to pump fluid through the fluid delivery pipe (102), and the controller being configured to control the pump (202).

4. The system of claim 3, wherein the controller is configured to implement two injection modes for controlling the pump (202), wherein a first injection mode is used when the processor determines that the nozzle (104) is moving along the occlusal surface of the tooth, and wherein a second injection mode is used when the processor determines that the nozzle (104) is moving along the lateral surface of the tooth.

5. The system according to any one of claims 1 to 4, wherein the interdental sensor (2002) comprises: A pressure sensor is used to measure the pressure of the fluid in the fluid delivery pipe (102); or A flow sensor is used to measure the flow rate of the fluid in the fluid delivery pipe (102); or At least two electrodes are located at the tip of the nozzle (104).

6. The system according to any one of claims 1 to 4, further comprising one or more of the following: A force sensor is used to sense the force applied by the user between the nozzle (104) and the teeth; Accelerometer; as well as A gyroscope is used to measure the angle of the nozzle (104) relative to the tooth.

7. The system according to any one of claims 1 to 4, wherein the processor is configured to determine, based on a machine learning algorithm, that the nozzle (104) is moving along the occlusal surface of the tooth, wherein the machine learning algorithm is trained to identify the occlusal surface of the tooth and the lateral surface of the tooth based on signals from at least the interdental sensor (2002) and the motion sensor (2004).

8. The system according to any one of claims 1 to 4, wherein the critical distance is at least 0.5 cm.

9. The system according to any one of claims 1 to 4, further comprising: The toothbrush head (106) includes multiple bristles (108). The toothbrush head also includes the nozzle (104), and The system further includes a motor and a second controller, the motor being used to control the toothbrush head (106) during brushing motion, the second controller being configured to control the motor to implement two brushing modes, wherein a first brushing mode is used when the processor determines that the nozzle (104) is moving along the occlusal surface of the teeth, and wherein a second brushing mode is used when the processor determines that the nozzle (104) is moving along the lateral surface of the teeth.

10. A computer program product including computer program code, which, when executed on a processor, causes the processor to perform a method for determining whether an oral irrigation system is on the occlusal surface of a tooth, the method comprising: Determine the displacement of the nozzle (104) of the oral irrigation system; Determine whether the nozzle (104) is in the interdental space; as well as The following operation determines that the nozzle (104) is moving along the occlusal surface of the tooth: It is determined that the displacement of the nozzle (104) is greater than a critical distance, and it is determined that the nozzle (104) has not been positioned in the interdental space during the displacement of the nozzle (104).

11. The computer program product of claim 10, wherein when the computer program code is executed on a processor, the processor performs the method, the method comprising: It is determined that the nozzle (104) is moving along the side of the tooth by determining that the displacement of the nozzle (104) is greater than the critical distance and that the nozzle (104) was once positioned in the interdental space during the displacement of the nozzle (104).

12. The computer program product of claim 10, wherein when the computer program code is executed on a processor, the processor performs the method, the method comprising: Implement two spray modes for controlling the pump (202) of the oral irrigation system, wherein a first spray mode is used when it is determined that the nozzle (104) is moving along the occlusal surface of the teeth, and wherein a second spray mode is used when it is determined that the nozzle (104) is moving along the lateral surface of the teeth; and / or Two brushing modes are implemented for controlling the motor that drives the toothbrush head, wherein the first brushing mode is used when it is determined that the nozzle (104) is moving along the occlusal surface of the teeth, and wherein the second brushing mode is used when it is determined that the nozzle (104) is moving along the lateral surface of the teeth.

13. A processor having a computer program product according to claim 10 stored thereon.

14. A handle for an oral irrigation system, wherein the handle comprises: An interface for connecting the handle to an oral irrigation head; Fluid delivery tube (102) for delivering fluid to the oral irrigation head; Pump (202) is configured to pump fluid to the fluid delivery pipe (102) based on pump configuration; and The processor according to claim 13 is used to control the pump.

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