Functional impression preparation method based on bidirectional creep of oral mucosa and impression materials

Abstract

The present invention belongs to the field of oral medical technology, and proposes a functional impression preparation method based on bidirectional creep of oral mucosa and impression material. By using a bidirectional creep process under a pressure of a specific size and completely evenly distributed, the impression material and the oral mucosa are fully shaped to each other, thereby obtaining the optimal functional state of the mucosa. This method is combined with a pressure-controlled liquid balance to prepare a denture impression auxiliary instrument, which can achieve completely uniform force on the supporting area mucosa and the remaining teeth and controllable pressure; using a light-curing oral material with a certain viscosity, under a relatively constant bite force, after fully shaping with the mucosa within a specific time, the denture supporting area impression is finally obtained by light-curing the material. Current clinical experiments have shown that this method significantly improves the dislocation force of full dentures, can effectively solve the problems of mucosal pain and ulceration caused by poor fit of full dentures or uneven tissue force, and has achieved significant clinical results.

Description

Technical Field

[0001] The invention relates to the technical field of oral dentures, and in particular to a method for preparing a functional impression based on bidirectional creep of oral mucosa and impression materials. Background Art

[0002] In prosthodontics, in order to ensure that the denture (false tooth) can fit the patient's mouth perfectly, it is a critical step to accurately reflect the anatomical structure of the patient's mouth. This involves how to correctly obtain a model of the soft and hard tissues in the mouth, that is, the impression making process, which is an important basic link.

[0003] The oral mucosa is not a rigid structure, but has a certain degree of plasticity and elasticity. Although the oral mucosa, which is closely related to denture restoration, appears to be continuous and smooth on the surface, its actual internal structure is uneven in thickness, resulting in differences in the mechanical properties of each part. During the preparation of functional impressions, the oral mucosa is subjected to pressure and will gradually and continuously deform over a certain period of time, and the deformation of each part varies. Traditional impression materials gradually harden during use and cannot reflect the changing mucosal morphology. This problem leads to problems such as poor retention and uncomfortable wearing of the final denture or restoration.

[0004] The digital impression method obtains three-dimensional oral data through scanning and is also based on the oral tissue morphology at a certain moment and cannot reflect the dynamic deformation of the oral mucosa under the functional state.

[0005] The oral mucosa has the characteristics of a non-Newtonian fluid, which is specifically manifested in a nonlinear relationship between shear rate and shear stress. When pressure is applied to the mucosa, the faster the pressure is applied, the greater the viscosity of the mucosa will be, the stronger the resistance it produces, and correspondingly, the smaller the deformation. In the process of making the impression, if the deformation interaction speed between the impression material and the oral mucosa is too fast, it is difficult to obtain an impression that can reflect the functional state of the mucosa. Because this rapid interaction cannot make the impression material and the oral mucosa fully adapt to and shape each other, it is impossible to accurately record the true form of the mucosa in a functional state. During the research process, the inventor believes that only by slowly and gradually loading the impression material and the oral mucosa under functional pressure conditions, allowing the mucosa to gradually deform, and the impression material can gradually record this deformation, can the true and accurate anatomical form of the mucosa in a functional state be finally obtained, thereby laying a solid foundation for high-quality denture restoration.

[0006] In the invention application CN116549152A filed by the inventor in 2023, the problem of uniform pressure on the supporting mucosa and controllable pressure was solved. However, the impact of continuous variables brought about by the mucosal deformation process was not taken into account. How to prepare an oral impression with higher fit, higher precision, better wearing comfort, and stronger retention based on the unique tissue deformation characteristics of the oral mucosa is a technical problem that has not been solved in the industry at present, and it is also the purpose of the invention of this invention. Summary of the invention

[0007] In order to address the deficiencies and defects of the prior art, the inventors have conducted research and development experiments and continuously improved and innovated to provide a functional impression preparation method based on the bidirectional creep of oral mucosa and impression materials. By using a flexible light-curing oral material with a specific viscosity, with the assistance of the equipment disclosed in the CN116549152A invention application, the material is fully shaped with the mucosa over an extended specific time. After the simultaneous creep of the two is completed, the impression of the denture bearing area is obtained by light-curing the impression material. Through the first phase of clinical experiments, it was found that the dislocation force of full dentures for all patients was significantly improved. For patients with particularly low alveolar bones, the dislocation force of mandibular full dentures was significantly improved compared with the existing methods (see the embodiments). Moreover, for some patients who suffered from mucosal pain and ulceration caused by wearing full dentures, their adverse reactions were effectively improved. At the same time, the first dentures made had no obvious mucosal pain and ulceration reactions, which could greatly reduce the number of subsequent follow-up visits for denture adjustments, and achieved very good clinical results. It fundamentally solved a series of key clinical problems caused by the inconsistency between the full denture impression and the functional status of the tissue, optimized the full denture production process, and greatly facilitated the patient's overall denture restoration treatment medical process by reducing the number of follow-up visits.

[0008] Specifically: A functional impression preparation method based on bidirectional creep of oral mucosa and impression material comprises the following steps: Step S1, first prepare the basic tray; prepare a tray by conventional methods, make the upper and lower jaw ridges after appropriate adjustments, and form the basic tray after determining the occlusal relationship. The semi-transparent or transparent basic tray can be used directly or the basic tray can be digitally scanned, and the scanned digital file is 3D printed to obtain a digital replica tray. The subsequent steps are performed on this digital replica tray, which can facilitate the acquisition of experimental data. In addition, because the printed material can be selected as a transparent material, it is conducive to the subsequent solidification of the tissue surface material; Step S2, padding (covering) a layer of flexible light-curing oral material of uniform thickness on the tissue surface of the basic tray or the digitally replicated tray based on the basic tray, and wearing it into the corresponding position inside the patient's mouth; Step S3, connecting the visual bite force detection device (the device disclosed in CN116549152A) to the display device and starting it, inserting the occlusal end (fluid capsule) into the patient's oral cavity, above, below or between the basic support, and maintaining the patient's normal inter-jaw distance; the visual bite force detection device can display the current patient's bite force value in real time; Step S4, the patient maintains a biting posture, so that the oral mucosa and the flexible light-curing oral material are mutually subjected to force to perform mutual shaping creep, during which the display device is observed to make the biting force value reach a preset biting force value and the biting posture is always maintained, so that the biting force remains constant until a predetermined time is reached; Step S5, immediately photocuring the light-curing oral material on the tissue surface of the basic tray or the digital replica tray in the mouth, recording the morphology after creep, photocuring the oral material to form an optimized tray, and then preparing the final impression based on the optimized tray.

[0009] Furthermore, the photocurable oral material is any existing material in the oral medical industry that meets the requirements of the present invention or a new material with better flexibility and flowability that will be developed for this technology in the future. In step S3, the photocurable oral material is evenly padded on the tissue surface of the base tray, with a thickness of about 2 mm, and the shape is cut according to the size and shape of the tissue surface of the base tray to facilitate the padding material. Avoid light as much as possible throughout the process to prevent the material from curing and affecting the deformation performance. The photocurable model material used in this method is the photocurable model material of China Hu Ge Company. Before padding, the photocurable model material is heated and softened, for example, after preheating in warm water at 50-55°C, it has a more deformable flow characteristic after softening. With the above-mentioned processing technology and processing means, it can meet the use requirements and invention purposes of the present invention and produce outstanding technical effects. However, for the selection of this photocurable oral material, other similar materials can also be used instead.

[0010] Furthermore, the visual bite force detection device includes an observation display device, a pressure monitoring sensor device connected to the observation display device, and a fluid bag placed inside the oral cavity. The fluid bag is connected to the pressure monitoring sensor device, and can transmit the deformation force generated during biting to the pressure monitoring sensor device through the built-in fluid, and display the current bite force value on the observation display device. The preset bite force value is the range of chewing force values ​​under normal oral function, and the predetermined time is the time required for the oral mucosa and the impression material to creep each other to reach a balanced stable state. The determination of various working parameters has personalized requirements according to different patients, and is constantly optimized and improved according to the research progress.

[0011] Furthermore, the fluid bag contains liquid or gas.

[0012] Working principle of the present invention: In the present invention, the impression material refers to the material as a whole formed by the base tray or the digitally copied tray covered with a flexible light-cured oral material liner. In the present invention, creep is the phenomenon that the deformation of a solid material increases with time under the condition of keeping the stress constant. It is different from plastic deformation. Plastic deformation usually occurs after the stress exceeds the elastic limit, while creep can also occur when the stress is less than the force applied by the elastic limit as long as the stress action time is long enough. That is, the oral mucosa is slowly deformed over time under the action of constant stress. Bidirectional creep refers to the mutual plastic deformation of the oral mucosa and the impression material under the action of the bite force. During the occlusion process, the oral mucosa and the oral impression material interact with each other and gradually adapt to each other's shapes, that is, the mucosa gradually deforms, and the impression material is gradually recorded accordingly. Therefore, the present invention uniformly pads the light-curing oral material on the tissue surface of the base support, which can better fit the oral mucosa during the pressure process and maintain a certain material strength and fluidity. This plasticity can be fully and evenly filled between the tissue surface and the mucosa after being stressed, and the force is transmitted back to the tissue surface, thereby realizing the mutual shaping effect between the tissue surface and the oral mucosa. In this process, using a visual bite force detection device to monitor the bite force in real time is also a key step to ensure that the bite force always remains constant, controllable and evenly distributed during the bidirectional creep shaping process, so that the present scheme is carried out under quantitative and controllable conditions, thereby getting rid of the weakness of traditional technology that needs to rely on experience and the patient's own conditions to carry out.

[0013] In particular, the present invention is more conducive to establishing good wearing stability for patients with very severe alveolar ridge resorption.

[0014] After using the creep technology of the present invention: Minor defects that occur when making a tray using conventional methods can be compensated, such as poor fit, insufficient edge stretching, and sharp edges. These can be compensated to a large extent by squeezing and wrapping the tray with the light-cured model material of the liner during the creep process.

[0015] Through the interaction between light-cured oral materials and mucosa for a certain period of time, the yield of the mucosa can be fully utilized. Compared with conventional methods, the support tissue can wrap the alveolar ridge more fully, the contact area is appropriately increased, and the tissue surface adaptability is improved, and the closure is better.

[0016] The two-way interactive process not only obtains the functional morphology of the alveolar ridge and related covering soft tissues, but also the functional morphology of related soft tissues such as muscles and frenulum (including but not limited to swallowing saliva when biting the water bag, tightening and movement of the lips, etc.). Therefore, the functional impression preparation technology using bidirectional creep of oral mucosa and impression material can avoid the damage to the edge seal of the denture due to the movement of muscles and frenulum during impression preparation.

[0017] For older patients with sensitive tissues, the impressions made by this impression technology are extremely accurate. Patients rarely experience pain after wearing the teeth, and there is no need to adjust the dentures multiple times later. Patients dare to use denture bite objects, and the bite force is balanced, which is conducive to the retention of the dentures.

[0018] The beneficial technical effects of the present invention compared with the prior art are as follows: (1) The mucosal morphology under the functional state of the oral cavity is truly obtained: by combining a constant bite force with a soft light-curing oral material and a visual bite force detection device, the possibility of bidirectional creep between the oral mucosa and the soft light-curing oral material is achieved under the action of a constant bite force for a specific time, ensuring that the impression material can fully adapt to the shape of the oral mucosa and eventually reach the state after creep, thereby recording a more realistic and accurate morphology under the functional state of the oral cavity.

[0019] (2) Enhance the stability and comfort of dentures: Since the impression material has fully adapted to the functional state of the oral mucosa during the bidirectional creep process, the dentures made can better maintain consistency of fit after being worn by the patient, and can maintain a high degree of fit whether in occlusion or at rest. This high degree of fit can effectively increase the dislocation force of the denture, avoid and eliminate the loosening of the denture during daily use, and improve the comfort and reliability of the patient, especially for patients with very severe alveolar resorption; since the impression material and the oral mucosa have reached a good state of adaptation during the bidirectional creep process, the dentures made can better match the shape of the oral mucosa in actual use, reduce adverse reactions such as mucosal pain and ulceration caused by wearing the denture, and improve comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a sample diagram of the morphology of the basic support in a specific embodiment of the present invention; Figure 2 for Figure 1 Schematic diagram of the digitally replicated support generated by digital 3D printing of the basic support; Figure 3 A photo of a light-cured oral material and a uniform liner in a specific embodiment of the present invention on a digitally replicated support tissue surface; Figure 4 A schematic diagram of a preheating process of a light-curing oral material in a specific embodiment of the present invention; Figure 5 It is a schematic diagram of the occlusal fluid sac after the patient wears the digitally replicated support containing the light-cured model material in a specific embodiment of the present invention; Figure 6 It is a schematic diagram of a process of performing a constant bite force test on a patient in a specific embodiment of the present invention; Figure 7 It is a schematic diagram of curing a light-curable oral material in a specific embodiment of the present invention; Figure 8 This is a photo of the optimized tray prepared in a specific embodiment of the present invention; Fig. 9 This is a comparison chart of the final impressions prepared in the specific implementation manner of the present invention; Group A in the figure is the final impression of the traditional method, Group B is the final impression of the creep 30Kpa (300g) 10min method, and Group C is the final impression of the creep 60Kpa (600g) 10min method. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0022] Example 1: Functional impression preparation method based on bidirectional creep of oral mucosa and impression material Steps: 1. Preparation of basic support: According to the conventional oral restoration technology requirements, the basic tray is made. The basic tray is the basic structure for subsequent impression preparation. Its shape and size should roughly conform to the basic form of the patient's mouth, providing a support framework for subsequent lining impression materials and occlusal shaping.

[0023] 2. Light-curing dental material processing and lining: Preheat the light-curing dental material in warm water at 50-55°C (preferably after applying it to the tissue surface of the implant and before use) to make it more deformable and plastic. This step is to allow the impression material to flow better and fit the oral mucosa when under pressure, while maintaining the material strength to a certain extent, so as to form a good filling and interaction force transmission between the tissue surface and the mucosa.

[0024] The preheated light-cured oral material is evenly and completely laid on the tissue surface of the base. Uniform thickness can ensure that the contact and interaction between the material and the oral mucosa are relatively consistent during the occlusion process, avoiding uneven force and inaccurate impression caused by uneven thickness.

[0025] Visual bite force testing equipment preparation and placement: Connect the display device of the visual bite force detection device to the bite end pressure monitoring sensor device to ensure that the device works normally and can display the bite force value in real time.

[0026] The fluid bag (which can be an air bag and trachea, or a water bag and a water tube connected to their respective sensors) at the occlusal end of the visual bite force detection device is placed inside the patient's mouth, above, below or between the basic support, while maintaining a normal inter-jaw distance; the fluid bag contains liquid or gas, and its function is to transmit the deformation force generated during occlusion to the pressure monitoring sensor device through the built-in fluid, and then display the current bite force value on the observation display device, providing a monitoring basis for maintaining a constant bite force in the future. For the specific structural principle, please refer to the invention application CN116549152A (a method and device for making denture impressions based on pressure-controlled liquid balance). The visual bite force detection device is the key equipment for this embodiment. Based on the visual implementation of the bite force device, the patient can continuously maintain a specific bite force during the occlusion process and continue for a period of time, so as to achieve a stable and useful continuation of the mutual creep effect between the mucosa and the light-curing model material.

[0027] Bite shaping process: The patient maintains a biting posture, so that the oral mucosa and the curable soft oral impression material are subjected to mutual forces, and undergo mutual shaping creep. In this process, the oral mucosa will gradually deform due to the pressure of the impression material and the force generated by the bite, and its own viscoelasticity will make it produce a force to resist deformation; and the impression material will gradually adapt to the shape of the oral mucosa under the combined action of the reaction force of the oral mucosa and the bite force, and will also creep itself.

[0028] Observe the display device, adjust the bite force value and keep it at the preset bite force value between 30Kpa (300g) and 60Kpa (600g) for 10 minutes. Constant bite force is the key factor to ensure the stable bidirectional creep between the impression material and the oral mucosa. It can evenly distribute the pressure between the two, avoid the creep anomaly caused by local pressure fluctuations, and allow the impression material and the oral mucosa enough time to shape each other, so as to better adapt to the complex shape inside the oral cavity and improve the suitability of the impression.

[0029] Impression curing and final impression preparation: After the occlusal shaping is completed, the light-cured model material is cured immediately, and the base tray is removed after curing. At this time, the light-cured oral impression material on the base tray has recorded the shape after creep, forming an optimized tray. The light-curing process can fix the shape of the impression material on the basis of adapting to the shape of the oral mucosa, so as to obtain a final impression that can truly reflect the optimization under the consideration of the two-way creep variables of the oral mucosa and the impression material; when the patient has no obvious soft tissue undercut, directly curing the material used for the impression in the mouth can obtain better accuracy.

[0030] The final impression is prepared based on the optimized tray, which can be used for subsequent oral restoration work such as denture making. Since the bidirectional creep of the oral mucosa and the impression material is fully considered, the denture can maintain a high degree of fit consistency after being worn by the patient, both during the occlusion process and the rest process, effectively improving the dislocation force of the denture and reducing the patient's adverse reactions such as mucosal pain and ulceration caused by wearing dentures.

[0031] Example 2: Experimental Control A self-controlled experimental design was adopted. The creep technology group was an operation method based on the steps and principles of Example 1, and the traditional method group was a traditional impression operation method; and the patients of the experimental subjects were all the same patients. The specific experimental conditions and results are as follows: Traditional impression method, that is, personalized tray with silicone rubber heavy body + light body to make impression. This technology is described in the impression making chapter of the eighth edition of the National Health Commission's planned textbook "Oral Prosthodontics", editor-in-chief: Zhao Yimin. Some patients cannot reach a bite force of 600g, so there is only data for the 300g bite force group.

[0032] Test 1: Subject Dong Moucun, 2024.07.19

[0033] Average dislocation force: traditional method (2.9375N) < creep technique group (10.5625N).

[0034] Test 2: Subject Zhan Mouqin, 2024.08.05

[0035] Average dislocation force: traditional method (1.5N) < creep technology group (5.375N).

[0036] Test 3: Subject Zhao Mouxian, 2024.08.16

[0037] Average dislocation force: traditional method (8.8125) < creep technology group—30 kpa (300 g) · 10 min (14.3125 N) < creep technology group—60 kpa (600 g) · 10 min (18.0625 N).

[0038] Test 4: Subject Zhou Moubai, 2024.08.26

[0039] Average dislocation force: traditional method (15.19N) < creep technology group—30kpa (300g)·10min (19.375N) < creep technology group—60kpa (600g)·10min (20.1875N).

[0040] Test 5: Subject Duan Mouxian, 2024.08.29

[0041] Average dislocation force: traditional method (4.68125N) < creep technology group (7.375N).

[0042] Test 6: Subject Gai Mouxian, 2024.08.30

[0043] Average dislocation force: traditional method (2.625N) < creep technique group (5.065N).

[0044] Test 7: Subject Li Mouhong, 2024.09.30, some groups were unable to dislocate

[0045] Average dislocation force: traditional method (10.25N) < creep technology group—30kpa (300g)·10min (15.25N) < creep technology group—60kpa (600g)·10min (16.375N).

[0046] Test 8: Subject Li Mouwu, 2024.10.25

[0047] Average dislocation force: traditional method (6.875N) < creep technology group—30kpa (300g)·10min (12.75N) < creep technology group—60kpa (600g)·10min (14.4375N).

[0048] The above 8 groups of experimental results show that in the relevant tests conducted on different subjects, the average dislocation force of the creep technology group under different pressure conditions, such as 30kpa (300g), 60kpa (600g), 140kpa (1400g), etc., is significantly higher than that of the traditional method group, indicating that creep technology has advantages in clinical trials. From the data of multiple subjects from test 1 to test 8, when comparing the traditional method group and the creep technology group (different pressure conditions), except for a few cases (such as some subjects have special circumstances in some tests, such as Gai Mouxian's bite problem, Li Mouhong's part of the group can not be dislocated, etc., but the overall trend is still in line with), the overall result shows that the average dislocation force of the traditional method group is less than that of the creep technology group. For example, in Zhou Moubai's test, the average dislocation force of the traditional method group was 15.19N, the creep technology group 30kpa (300g) 10min was 19.375N, and the creep technology group 60kpa (600g) 10min was 20.1875N. It can be clearly seen that the average dislocation force of the traditional method group was lower than that of the creep technology group under different pressure conditions.

[0049] For the subjects who underwent tests under various pressure conditions (such as Zhao Mouxian, Zhou Moubai, Li Mouhong, and Li Mouwu), there was a trend that the traditional method group was less than the creep technology group, and 30 kpa (300 g) 10 min was less than 60 kpa (600 g) 10 min in the creep technology group, which further indicates that with the change of continuous bite force conditions, the creep technology group may perform better in dislocation force.

[0050] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A functional impression preparation method based on bidirectional creep of oral mucosa and impression material, characterized in that The following steps are involved: Step S1, selecting a transparent material to prepare a base support; Step S2, padding a flexible light-curing oral material on the tissue surface of the base support, and wearing it into the corresponding position inside the patient's oral cavity; Step S3, connecting the visual bite force detection device to the display device, and placing the bite end into the patient's oral cavity above, below or between the basic support; the visual bite force detection device can display the current bite force value of the patient in real time; Step S4, the patient maintains the biting posture, during which the display device is observed, so that the biting force value reaches the preset biting force value and the biting posture is always maintained, so that the oral mucosa and the flexible light-curing oral material are mutually subjected to force and creep and shape each other, until the predetermined time is reached; Step S5, photocuring the photocurable oral material on the tissue surface of the base tray in the mouth, recording the morphology after creep, optimizing the tray based on the overall composition of the base tray and the photocurable oral material, and preparing the final impression based on the optimized tray.

2. The method for preparing a functional stamp according to claim 1, characterized in that: Step S1 also includes: digitally scanning the pre-prepared basic tray, 3D printing the scanned digital file, and obtaining a digital replica tray, and the basic trays in steps S2, S3, and S4 can all use the digital replica tray.

3. The method for preparing a functional stamp according to claim 1, characterized in that: The light-curable oral material is an oral medical light-curable material with fluid viscosity. In step S3, the oral medical light-curable material with fluid viscosity is evenly padded on the tissue surface of the base support.

4. The method for preparing a functional stamp according to claim 1, characterized in that: The preset bite force value is a range of chewing force values ​​under normal oral function, and the predetermined time is the time required for the oral mucosa and the impression material to creep mutually and reach a balanced stable state.

5. The method for preparing a functional stamp according to claim 1, characterized in that: The visual bite force detection device includes an observation and display device, a pressure monitoring sensor device connected to the observation and display device, and a fluid bag placed inside the oral cavity. The fluid bag is connected to the pressure monitoring sensor device and can transmit the deformation force generated during biting to the pressure monitoring sensor device through the built-in fluid, and display the current bite force value on the observation and display device.

6. The method for preparing a functional stamp according to claim 5, characterized in that: The fluid bag contains liquid or gas.

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