Laser caries removal device and operation method thereof

Abstract

The invention discloses a laser caries removing device. The laser caries removing device comprises a laser, a half-wave plate, a polarizer, a telescope group and a focusing lens, the laser is used for emitting a laser beam, the laser beam enters the telescope group after the power of the laser beam is adjusted to target power through the half-wave plate and the polarizer, and after the diameter of the laser beam is adjusted to target diameter through the telescope group, the laser beam is focused by the focusing lens to emit a treatment beam within a preset energy density range. According to the technical scheme, the power of the laser beam can be adjusted based on the half-wave plate and the polarizer, the diameter of the laser beam can be adjusted based on the telescope set, and therefore it is ensured that the energy density of the laser beam is kept within the preset range after the laser beam is focused through the focusing lens. Furthermore, according to different laser ablation thresholds between the decayed tooth and the healthy dentin, the laser can be controlled to accurately act on the decayed tooth tissue for ablation, the healthy dentin is prevented from being damaged, and accurate, efficient and safe decayed tooth treatment is realized. The invention further discloses an operation method of the laser caries removing device.

Description

Technical Field

[0001] This application relates to the field of oral medical technology, and particularly to a laser caries removal device and its operation method. Background Art

[0002] Dental caries, commonly known as tooth decay, is a common oral disease mainly caused by acidic substances produced by bacterial metabolism eroding the hard tissues of the tooth. In modern life, the incidence of dental caries remains high, and its form and impact are becoming increasingly complex, significantly affecting the oral health and quality of life of patients.

[0003] Existing dental caries removal mainly involves grinding the decayed part of the tooth with mechanical tools (such as high-speed turbine drills). This method of caries removal causes obvious pain and discomfort to patients, and also generates unnecessary reaction forces, noise, and vibrations, reducing the accuracy and precision of the operation. Inevitably, healthy tooth tissues are ground away, seriously affecting the operation effect and patient experience.

[0004] Therefore, it is necessary to improve the existing caries removal methods. Summary of the Invention

[0005] This application provides a laser caries removal device and its operation method, aiming to solve the problem that the mechanical caries removal method in the existing technology seriously affects the operation effect and patient experience.

[0006] To achieve the above object, this application proposes a laser caries removal device, including a laser, a half-wave plate, a polarizer, a telescope group, and a focusing lens;

[0007] The laser is used to emit a laser beam, and the laser beam is adjusted to the target power by the half-wave plate and the polarizer and then incident on the telescope group. After the diameter of the laser beam is adjusted to the target diameter by the telescope group, a treatment beam within a preset energy density range is focused and emitted by the focusing lens.

[0008] In some embodiments, the laser is a femtosecond laser, and the wavelength of the emitted laser beam is between 990 and 1100 nm.

[0009] In some embodiments, the focusing lens is replaceably disposed in the optical path, and the focal length of the focusing lens is between 90 and 110 mm.

[0010] In some embodiments, it further includes a light-shielding baffle, and the light-shielding baffle is disposed on the reflection path of the polarizer for the laser beam.

[0011] In some embodiments, it further includes a photographing component, and the photographing component includes a light source, a semi-transparent and semi-reflective mirror, and a charge-coupled camera;

[0012] The light source is used to emit a white light beam, which is transmitted through the semi-transparent and semi-reflective mirror and then incident on the focusing lens, and is focused and emitted by the focusing lens along the same focusing path as the treatment beam; and, the white light beam reflected back along the original path is reflected to the photosensitive coupling camera for imaging when it reaches the semi-transparent and semi-reflective mirror.

[0013] In some embodiments, a dichroic mirror is further included, and the dichroic mirror is used to combine the treatment beam and the white light beam so that the treatment beam and the white light beam are incident on the focusing lens along the same path.

[0014] The present application also provides an operation method of a laser caries removal device, including:

[0015] Receiving a preset energy density range of the treatment beam;

[0016] Determining the target power and target diameter of the laser beam according to the preset energy density range;

[0017] Based on the target power and the target diameter, the device is adjusted to output a treatment beam that meets the preset energy density range in the device and acts on the patient's teeth.

[0018] In some embodiments, before receiving the preset energy density range of the treatment beam, it further includes:

[0019] Selecting caries and healthy dentin as experimental samples and keeping the surfaces of the experimental samples clean;

[0020] Adjusting the parameters of the laser so that the single-pulse energy density irradiates the experimental samples in an equal-increment manner, and recording the ablation pit morphology of the experimental samples at different energy densities;

[0021] Obtaining a first energy density when caries form ablation pits and a second energy density when healthy dentin forms ablation pits to determine that the preset energy density is between the first energy density and the second energy density.

[0022] In some embodiments, the determining the target power and target diameter of the laser beam according to the preset energy density range includes:

[0023] Obtaining the focal length parameter of the focusing lens;

[0024] Based on the action range of the treatment beam on the teeth, determining the diameter range of the laser beam, and selecting and determining the target diameter within the diameter range of the laser beam;

[0025] Calculate the power range of the laser beam according to the target diameter, the focal length parameter, and the preset energy density range, and select and determine the target power within the power range.

[0026] In some embodiments, calculating the power range of the laser beam according to the target diameter, the focal length parameter, and the energy density range, and selecting and determining the target power within the power range includes:

[0027] Calculate a first power value of the laser beam power according to the target diameter, the focal length parameter, and the first energy density;

[0028] Calculate a second power value of the laser beam power according to the target diameter, the focal length parameter, and the second energy density;

[0029] Select and determine the target power between the first power value and the second power value.

[0030] The technical solution of the present application proposes a laser caries removal device. The laser caries removal device includes a laser, a half-wave plate, a polarizer, a telescope group, and a focusing lens; the laser is used to emit a laser beam, and after the power of the laser beam is adjusted to the target power through the half-wave plate and the polarizer, it is incident on the telescope group, and after the diameter of the laser beam is adjusted to the target diameter by the telescope group, a treatment beam within a preset energy density range is focused and emitted by the focusing lens. The technical solution of the present application can adjust the power of the laser beam based on the half-wave plate and the polarizer and can adjust the diameter of the laser beam based on the telescope group, so as to ensure that the energy density of the laser beam remains within the preset range after being focused by the focusing lens. Furthermore, according to the different laser ablation thresholds of caries and healthy dentin, the laser can be precisely controlled to act on the caries tissue, avoiding damage to healthy tissue, and realizing precise, efficient, and safe caries treatment. The present application also discloses an operation method of a laser caries removal device. Description of the Drawings

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings, where:

[0032] Figure 1 It is a schematic structural diagram of a laser caries removal device according to an embodiment of the present application;

[0033] Figure 2 It is a schematic diagram of the energy density distribution of the treatment beam after passing through the focusing lens according to an embodiment of the present application;

[0034] Figure 3 This is a schematic flowchart of the operation method of a laser caries removal device according to an embodiment of the present application;

[0035] Figure 4 is Figure 3 a schematic flowchart for confirming the target power and target diameter of the laser beam in Detailed implementation manners

[0036] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0037] It should be noted that all directional indications (such as up, down, left, right, front, back,...) in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0038] It should also be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may be a middle element at the same time. When an element is referred to as "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time.

[0039] In addition, the descriptions involving "first", "second", etc. in the present application are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions appears to be contradictory or unable to be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0040] Referring to Figure 1 as shown, the present application provides a laser caries removal device. The laser caries removal device includes a laser 1, a half-wave plate 4, a polarizer 3, a telescope group 6, and a focusing lens 12 that are sequentially arranged along the optical path.

[0041] The main function of the laser 1 is to emit a high-intensity laser beam 2. After being adjusted by the half-wave plate 4, the polarization state of the laser beam 2 changes, thereby enabling the adjustment of the power of the laser beam 2. Subsequently, through further screening and adjustment by the polarizing mirror 3, the power of the laser beam 2 is precisely controlled to the target power. The adjusted laser beam 2 then enters the telescope group 6, and the role of the telescope group 6 is to adjust the diameter of the laser beam 2 to ensure that it reaches the predetermined target diameter. Finally, the precisely adjusted laser beam 2 is focused by the focusing lens 12 to form a treatment beam with a preset energy density for removing the carious part on the tooth 13.

[0042] It can be understood that due to demineralization and increased organic matter in the carious tissue of the tooth 13, its optical scattering and absorption characteristics change, making dental caries more easily ablated by the laser, and the ablation threshold is relatively low. The main component of healthy dentin is still hydroxyapatite, which has a very low absorption of laser in the near-infrared band. The ablation of dentin by the laser mainly relies on the ionization effect brought by the high-intensity laser, so the ablation threshold is relatively high. Furthermore, since the ablation threshold of dental caries is lower than that of healthy dentin, when the laser parameters are adjusted so that the treatment beam meets the preset energy density condition, the treatment beam can selectively act on the carious part without damaging the healthy dentin, achieving precise treatment.

[0043] In addition, the present application aims to use the laser to perform ablation treatment on the carious part of the patient's tooth 13. Furthermore, it can avoid the pain, discomfort, as well as unnecessary reaction forces, noise, and vibrations generated when traditional mechanical tools are used to grind dental caries, and improve the accuracy and precision during surgical treatment.

[0044] To ensure the treatment effect, the laser 1 is a femtosecond laser, and the wavelength of the emitted laser beam 2 is between 990 and 1100 nm.

[0045] Specifically, the laser 1 is a ytterbium-doped femtosecond laser, which has an ultrashort pulse width and an extremely high peak power, and can deposit energy into the carious tissue in an extremely short time. Since almost no thermal effect is generated, it can avoid thermal damage, reduce postoperative pain and complications, and improve patient comfort. And when the wavelength of the laser beam 2 is between 990 and 1100 nm (near-infrared band), it can reduce the absorption of the laser by the hydroxyapatite component in the healthy dentin, which is beneficial for the treatment beam to treat deeper carious sites.

[0046] Furthermore, the focusing lens 12 can be replaceably arranged in the optical path, and the focal length of the focusing lens 12 is between 90 and 110 mm. The focusing lens 12 is designed to focus the laser beam 2 onto the carious area in the tooth 13 to form a high-energy density light spot for achieving precise treatment.

[0047] Among them, the focusing lens 12 is installed in the optical path through a modular design, which is convenient for disassembly and replacement. Users can select focusing lenses 12 with different focal lengths according to treatment needs, improving the flexibility and adaptability of the device and meeting the requirements of different treatment scenarios. The focal length of the focusing lens 12 is moderate, between 90 and 110 mm, so that the focusing lens 12 can achieve a balance between the focused spot size and the treatment depth, suitable for the treatment needs of different tooth parts.

[0048] In addition, the device further includes a light-shielding baffle 5. As Figure 1 shown, the light-shielding baffle 5 is arranged on the reflection path of the polarized mirror 3 for the laser beam 2. The light-shielding baffle 5 is used to block or absorb the laser beam 2 reflected by the polarized mirror 3, which can prevent the reflected laser beam 2 from interfering with or damaging other components inside the device, improving the safety and stability of the device.

[0049] And in some embodiments, the device further includes a photographing component. The photographing component includes a light source 7, a semi-transmissive and semi-reflective mirror 8, and a charged couple device camera 9. As Figure 1 shown. The light source 7 is used to emit a white light beam 10. The white light beam 10 passes through the semi-transmissive and semi-reflective mirror 8 and then enters the focusing lens 12, and is focused and emitted by the focusing lens 12 along the same focusing path as the treatment beam. And the white light beam 10 reflected back along the original path is reflected to the charged couple device camera 9 for imaging when it reaches the semi-transmissive and semi-reflective mirror 8.

[0050] In this application, by further providing the photographing component, the device can obtain the image information of the carious area in the tooth 13 in real time during the treatment process. Among them, the white light beam 10 shares the same optical path with the laser beam 2 through the semi-transmissive and semi-reflective mirror 8, ensuring the consistency between the imaging and the treatment area, and improving the accuracy and relevance of the image. After receiving the reflected white light beam 10, the charged couple device camera 9 can capture a high-definition image of the surface of the tooth 13, and the image can be used for diagnosis before treatment, monitoring during treatment, and evaluation of the treatment effect after treatment.

[0051] Therefore, through the integration of the photographing component, the device not only realizes precise treatment, but also provides visual treatment feedback, enhancing the controllability and effect of the treatment.

[0052] Furthermore, the device further includes a dichroic mirror 11. The dichroic mirror 11 is used to combine the treatment beam and the white light beam 10, so that the treatment beam and the white light beam 10 enter the focusing lens 12 along the same path. In this way, without additional optical path adjustment equipment, not only the structure of the device is simplified, but also the compactness and integration degree of the device are significantly improved.

[0053] In summary, the laser caries removal device provided by the technical solution of this application can adjust the power and diameter of the laser beam, so that the treatment laser after being focused by the focusing lens 12 has a preset energy density, so as to achieve targeted ablation treatment of dental caries.

[0054] This application also provides an operation method for a laser caries removal device. Refer to Figure 3 As shown, the operation method of the laser caries removal device includes:

[0055] Step S10, receiving the preset energy density range of the treatment light beam.

[0056] Before performing laser caries removal treatment, this step determines the preset energy range of the treatment light beam, aiming to ensure that the energy of the treatment light beam can effectively remove dental caries without damaging the surrounding healthy tooth tissues.

[0057] Among them, the preset energy density range of the treatment light beam can be achieved through the following steps:

[0058] 1. Experimental preparation

[0059] Select dental caries and healthy dentin as experimental samples, which can truly reflect the tissue reaction under laser irradiation; and keep the surface of the experimental samples clean to eliminate the influence of external factors on the experimental results. And ensure that the laser is in a normal working state, capable of outputting a stable and controllable laser beam. According to the experimental requirements, adjust the laser parameters, such as wavelength and pulse width, etc.

[0060] 2) Experimental steps

[0061] Adjust the single-pulse energy density of the laser in an equal-incremental manner and irradiate it on the experimental samples, and record the ablation pit morphology of the experimental samples at each energy density. Among them, the ablation pit morphology can be completed by devices such as a microscope and a scanning electron microscope.

[0062] 3) Determine the preset energy density range

[0063] Find the minimum energy density when obvious ablation pits are formed in dental caries, denoted as the first energy density, which is the lowest threshold for the laser to effectively remove dental caries. And, find the minimum energy density when obvious ablation pits are formed in healthy dentin, denoted as the second energy density, which is the lowest threshold for the laser to possibly damage healthy tooth tissues. Furthermore, according to the first energy density and the second energy density, determine the preset energy density range of the treatment light beam. This range should be between the first energy density and the second energy density to ensure that the treatment laser can effectively remove dental caries without damaging healthy tooth tissues.

[0064] Through experimental verification, the ablation threshold of dental caries is 0.2 J / cm 2; The ablation threshold of healthy dentin is 2.5 J / cm 2 .

[0065] Step S20: Determine the target power and target diameter of the laser beam according to the preset energy density range to provide the adjustment reference conditions for the device. The determination process is as follows Figure 4 shown and specifically includes:

[0066] Step S201: Obtain the focal length parameter of the focusing lens. The focal length determines the focusing degree of the laser beam after passing through the focusing lens. The focal length of this focusing lens can be obtained from the corresponding specification and is known data.

[0067] Step S202: Determine the diameter range of the laser beam based on the action range of the treatment beam on the tooth, and select and determine the target diameter within the diameter range of the laser beam. Among them, after matching with the focusing lens, the diameter range should make the spot of the focused treatment beam form on the carious tooth area to be treated. Within the determined diameter range, select a suitable laser beam diameter as the target diameter according to the treatment requirements and equipment capabilities. The selection of the target diameter should comprehensively consider factors such as treatment effect, safety, and equipment limitations.

[0068] Step S203: Calculate and obtain the power range of the laser beam according to the target diameter, focal length parameter, and preset energy density range, and select and determine the target power within the power range.

[0069] It can be understood that after the laser beam is focused by the focusing lens, the maximum energy density is at its focal point, as Figure 2 shown in the schematic diagram of the energy density distribution of the treatment beam after passing through the focusing lens. Therefore, it is necessary to ensure that the energy density at the focal point of the focusing lens is within this preset energy density range. Among them, the calculation formula for the energy density at the focal point of the focusing lens is:

[0070]

[0071] where E is the energy density, with the unit of joules per square centimeter (J / cm2); P is the total energy, with the unit of joules (J); A is the spot area at the focal point, with the unit of square centimeters (cm2).

[0072] After the laser beam passes through the focusing lens, the spot area A at the focal point can be calculated by the following formula:

[0073]

[0074] where d is the spot diameter at the focal point; and the spot diameter can be estimated by the following formula:

[0075]

[0076] Wherein, λ is the laser wavelength; f is the focal length of the focusing lens, D is the diameter of the incident laser beam. Substituting the spot area A into the energy density formula, the final calculation formula is obtained as follows:

[0077]

[0078] Furthermore, when the laser wavelength, the focal length of the focusing lens, and the diameter of the incident laser beam (target diameter) are determined, the laser power can be calculated according to the preset energy density value. Thus, when the preset energy density value is in the range parameter state, after substituting the relevant parameters into the formula for calculation, the two end values of the power of the laser beam can be calculated, thereby obtaining the power range of the laser beam. Specifically, it includes:

[0079] Calculating a first power value of the laser beam power according to the target diameter, focal length parameter, and first energy density; and calculating a second power value of the laser beam power according to the target diameter, focal length parameter, and second energy density; furthermore, determining that the power range of the laser beam is between the first power value and the second power value; and further selecting and determining the target power between the first power value and the second power value.

[0080] In this way, it is ensured that the maximum value of the energy density of the treatment beam is within the preset energy density, so that the focused treatment beam has an ablation effect on the carious part of the tooth and can prevent damage to the healthy dentin caused by excessive energy density. In a preferred solution, after being focused by the focusing lens, the energy density of the treatment laser at its focal point is close to the ablation threshold of the healthy dentin. When the ablation threshold of the healthy dentin is 2.5 J / cm 2 In this case, the energy density at the focal point is adjusted and controlled within the range of 2.0 - 2.2 J / cm 2 to have a strong ablation effect on the carious part of the tooth.

[0081] During the further laser caries removal treatment process, the focal point of the treatment beam can be gradually controlled to move from the tooth surface to the depth to complete the ablation of the carious part of the tooth, but its focal point cannot penetrate the tooth and fall on other dental tissues such as the gingiva. Or after taking a photo through the photographing component to generate a three-dimensional image, the depth at which the focal point of the treatment laser is located is controlled according to the image depth for precise control to prevent damage to other tissues of the tooth.

[0082] Step S30: Adjust the device based on the target power and the target diameter to output a treatment beam that meets the preset energy density range onto the patient's teeth.

[0083] Specifically, it can be to adjust the half-wave plate and the polarizing mirror to make the power of the laser beam reach the target power, and adjust the laser beam diameter to the target diameter by adjusting the telescope group. Finally, after the adjustment is completed, the device outputs the required treatment beam onto the patient's teeth.

[0084] The above are only partial or preferred embodiments of the present application. Neither the text nor the drawings can limit the scope of protection of the present application. Any equivalent structural transformation made by using the content of the specification and drawings of the present application under the overall concept of the present application, or any direct / indirect application in other related technical fields, is included in the scope of protection of the present application.

Claims

1. A laser caries removal device, characterized in that, It includes a laser, a half-wave plate, a polarizer, a telescope group, and a focusing lens; The laser is used to emit a laser beam. The laser beam is incident on the telescope group after its power is adjusted to a target power via the half-wave plate and the polarizer. After the diameter of the laser beam is adjusted to a target diameter by the telescope group, a treatment beam within a preset energy density range is focused and emitted by the focusing lens.

2. The laser caries removal device according to claim 1, wherein The laser is a femtosecond laser, and the wavelength of the emitted laser beam is between 990 and 1100 nm.

3. The laser caries removal device according to claim 1, characterized in that, The focusing lens is replaceably disposed in the optical path, and the focal length of the focusing lens is between 90 and 110 mm.

4. The laser caries removal device according to claim 1, characterized in that, It further includes a light-shielding baffle, which is disposed on the reflection path of the polarizer for the laser beam.

5. The laser caries removal device according to claim 1, characterized in that, It further includes a photographing assembly, which includes a light source, a beam splitter, and a charge-coupled camera; The light source is used to emit a white light beam. The white light beam is incident on the focusing lens after passing through the beam splitter, and is focused and emitted by the focusing lens along the same focusing path as the treatment beam; and, the white light beam reflected back along the original path is reflected to the charge-coupled camera for imaging when it reaches the beam splitter.

6. The laser caries removal device according to claim 5, characterized in that, It further includes a dichroic mirror, which is used to combine the treatment beam and the white light beam so that the treatment beam and the white light beam are incident on the focusing lens along the same path.

7. A method for operating a laser caries removal device, characterized in that, It includes: Receiving a preset energy density range of the treatment beam; Determining the target power and target diameter of the laser beam according to the preset energy density range; Based on the target power and the target diameter, performing device adjustment to output a treatment beam that meets the preset energy density range in the device and act on the patient's teeth.

8. The operating method of the laser caries removal device according to claim 7, characterized in that, Between receiving the preset energy density range of the treatment beam, it further includes: Selecting decayed teeth and healthy dentin as experimental samples and keeping the surfaces of the experimental samples clean; Adjusting the parameters of the laser so that the single-pulse energy density irradiates the experimental samples in an equal-increment manner, and recording the ablation pit morphology of the experimental samples at different energy densities; Obtaining a first energy density when the decayed teeth form ablation pits and a second energy density when the healthy dentin forms ablation pits to determine that the preset energy density is between the first energy density and the second energy density.

9. The operating method of the laser caries removal device according to claim 8, characterized in that, The determining the target power and target diameter of the laser beam according to the preset energy density range includes: Obtaining the focal length parameter of the focusing lens; Based on the action range of the treatment beam on the teeth, determining the diameter range of the laser beam, and selecting and determining the target diameter within the diameter range of the laser beam; Calculating and obtaining the power range of the laser beam according to the target diameter, the focal length parameter, and the preset energy density range, and selecting and determining the target power within the power range.

10. The operating method of the laser caries removal device according to claim 9, characterized in that, The calculating and obtaining the power range of the laser beam according to the target diameter, the focal length parameter, and the energy density range, and selecting and determining the target power within the power range includes: Calculate and obtain a first power value of the laser beam power according to the target diameter, the focal length parameter, and the first energy density; Calculate and obtain a second power value of the laser beam power according to the target diameter, the focal length parameter, and the second energy density; Select and determine the target power between the first power value and the second power value.

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