An apparatus for testing the polymerization shrinkage

Abstract

The utility model discloses a kind of polymerization shrinkage test device, comprising: non-light-transmitting cover body, is equipped with solidification cavity, solidification cavity is used to fill measured material;Photocuring machine is set in non-light-transmitting cover body outside, for the measured material in the solidification cavity is irradiated;Displacement sensor is set in the non-light-transmitting cover body, for the polymerization shrinkage of measured material is collected.The polymerization shrinkage test device, external light is completely isolated by non-light-transmitting cover body, ensure that only the light source of photocuring machine triggers material solidification, avoid the unexpected polymerization reaction caused by ambient light;Displacement sensor real-time monitoring micron level thickness change in material solidification process, far more than the accuracy of traditional mechanical measuring tool;Only non-light-transmitting cover body, photocuring machine, displacement sensor modular component, easy to assemble and reuse;Solidification cavity design ensures that measured material fills evenly, avoid the measurement error caused by complex structure, finally improve test accuracy.

Description

Technical Field

[0001] This invention belongs to the field of dental polymer substrate testing technology, and specifically relates to a polymerization shrinkage rate testing device. Background Technology

[0002] Many dental resins, such as composite resins, are photosensitive materials, typically cured by blue light of a specific wavelength (approximately 460nm–480nm). Yellow light, with a longer wavelength (approximately 550nm–590nm) and lower energy, does not activate photoinitiators like camphorquinone, thus preventing unintended curing before or during testing. Ordinary white light or natural light contains blue / ultraviolet components, which may affect the polymerization process. Using amber filters, such as sodium lamps, between yellow light exposures effectively filters out short-wavelength light, providing a stable testing environment. International standards such as ISO 4049 require controlled lighting conditions during testing. A yellow light environment ensures all tests are conducted without photocuring interference, making data from different laboratories comparable. To protect the stability of photosensitive reagents, some tests may involve photosensitive reagents or markers; yellow light prevents their degradation or reaction, ensuring measurement accuracy.

[0003] However, existing methods such as vernier calipers and volumetric methods are difficult to accurately measure micron-level polymerization shrinkage changes, leading to large data errors. In conventional tests, ambient light may affect the reaction of photocurable materials, causing distortion in shrinkage test results. Flowable polymer-based materials, such as resins, are prone to air bubbles or uneven distribution during filling, affecting shrinkage calculations. Existing methods do not standardize material pretreatment parameters such as settling time and data acquisition time, resulting in incomparable results. Therefore, to save on the construction cost of a photoluminescence room and to eliminate interference from unexpected wavelengths of light in the environment, this polymerization shrinkage testing device is used to replace the photoluminescence room, reducing the curing effect of unexpected light from the environment on the test samples and improving detection accuracy. Utility Model Content

[0004] To address the aforementioned problems, the primary objective of this invention is to provide a polymerization shrinkage rate testing device to solve the technical problems of large errors in calculating polymerization shrinkage rate and distorted test results in current technologies.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] This utility model provides a polymerization shrinkage rate testing device, comprising:

[0007] The non-transparent cover has a curing chamber for filling the material to be tested.

[0008] A photocuring machine, located outside the non-transparent cover, is used to irradiate the test material inside the curing chamber;

[0009] A displacement sensor, disposed within the opaque cover, is used to collect the polymerization shrinkage rate of the material under test.

[0010] By completely isolating external light through a non-opaque cover, the device ensures that only the light source from the UV curing machine triggers material curing, avoiding unintended polymerization reactions caused by ambient light. A displacement sensor monitors micron-level thickness changes during the curing process in real time, far exceeding the accuracy of traditional mechanical measuring tools. The polymerization shrinkage rate testing device requires only modular components—the non-opaque cover, the UV curing machine, and the displacement sensor—making it easy to assemble and reuse. The curing chamber design ensures uniform filling of the tested material, avoiding measurement errors caused by structural complexity. Therefore, through the collaborative design of the non-opaque cover and the displacement sensor, the two major challenges of light shielding and high-precision measurement are simultaneously solved in a single device.

[0011] Furthermore, the non-transparent cover includes:

[0012] Top panel, front panel, and side panels; among which,

[0013] The side panels are connected to opposite sides of the top panel; the front panel is connected to the top panel, and the front panel is connected between the two side panels; and,

[0014] The top plate, the front plate, and the two side plates together form the curing cavity.

[0015] The enclosed structure of the top plate, front plate, and side plates forms a closed curing cavity to avoid stray light interference.

[0016] Furthermore, the top plate includes:

[0017] The first and second sides are set relative to each other;

[0018] The third side connects the first side and the second side; wherein...

[0019] The two side panels are disposed on the first side and the second side; the front panel is disposed on the third side.

[0020] The geometric design of the curing chamber ensures that the light source uniformly covers the surface of the material under test, reducing measurement errors in shrinkage rate caused by uneven illumination.

[0021] Furthermore, the side plate extends along a first direction from the first side or the second side toward the side opposite to the top plate, forming a first height;

[0022] The front plate extends along the first direction from the third side toward the side opposite to the top plate, forming a second height; wherein,

[0023] The first height is equal to the second height;

[0024] The first direction is perpendicular to the extension direction of the top plate.

[0025] By ensuring that the side panels and front panel are at the same height, the internal dimensions of the curing chamber are consistent, making test results from different batches comparable. The stable chamber structure also guarantees the accuracy of displacement sensor data.

[0026] Furthermore, it also includes:

[0027] A matte coating is applied to the entire inner circumferential surface of the curing cavity.

[0028] Complete light blocking is achieved through a combination of a non-transparent enclosure structure and a matte coating.

[0029] Furthermore, the top plate has a first pre-drilled hole that extends through the top plate. The UV curing machine is used to irradiate the material to be tested inside the curing chamber through the first pre-drilled hole. The design of the first pre-drilled hole allows for precise control of the irradiation path of the UV curing machine.

[0030] Furthermore, the front panel has pre-drilled slots, with two slots spaced apart and extending through the front panel. These slots are used to display the readings of the displacement sensor. This design ensures both light shielding and ease of human-computer interaction.

[0031] Furthermore, the reserved groove is formed by recessing the front plate from the side away from the top plate toward the interior of the front plate.

[0032] Furthermore, the side plate has a second reserved hole, which extends through the side plate and is used to allow the power line of the displacement sensor to pass through.

[0033] Furthermore, the top plate is integrally connected to the side plate, and the top plate is integrally connected to the front plate. The non-transparent cover is a one-piece molded structure, which can avoid deformation caused by vibration or movement.

[0034] Compared with existing technologies, the beneficial effects of this application are as follows: The polymerization shrinkage rate testing device includes: a non-opaque cover with a curing chamber for filling the material to be tested; a light curing machine located outside the non-opaque cover for irradiating the material to be tested within the curing chamber; and a displacement sensor located inside the non-opaque cover for collecting the polymerization shrinkage rate of the material to be tested. Thus, the non-opaque cover completely isolates external light, ensuring that only the light source of the light curing machine triggers the material curing, avoiding unexpected polymerization reactions caused by ambient light, and solving the problem of light leakage that still exists in traditional yellow light or ordinary light shields, leading to measurement deviations in shrinkage rate; the displacement sensor monitors the micron-level thickness change during the material curing process in real time, far exceeding the accuracy of traditional mechanical measuring tools, thereby solving the problem that traditional methods cannot capture transient shrinkage behavior and that manual readings have large errors; the device only requires modular components such as the non-opaque cover, the light curing machine, and the displacement sensor, making it easy to assemble and reuse; the curing chamber design ensures uniform filling of the material to be tested, avoiding measurement errors caused by structural complexity. Therefore, by combining the design of a non-transparent cover with a displacement sensor, the two major challenges of light shielding and high-precision measurement can be solved simultaneously in a single device. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the non-transparent cover of the polymerization shrinkage rate testing device of this utility model.

[0036] Figure 2 yes Figure 1 A schematic diagram of the side panel of the light-transmitting cover in the Central African Republic.

[0037] Figure 3 yes Figure 1 A schematic diagram of the top plate of the light-transmitting dome in the Central African Republic.

[0038] Figure 4 yes Figure 1 Another perspective structural diagram of the light-transmitting cover in the Central African Republic.

[0039] In the figure: 100, non-transparent cover; 101, curing chamber; 110, top plate; 111, first side; 112, second side; 113, third side; 114, first reserved hole; 120, side plate; 121, second reserved hole; 130, front plate; 131, reserved groove; 140, back plate. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0041] To achieve the above objectives, the technical solution of this utility model is as follows:

[0042] See Figures 1-4 This utility model provides a polymerization shrinkage rate testing device, including: a non-transparent cover 100, which is provided with a curing cavity 101 for filling the material to be tested; a light curing machine, which is located outside the non-transparent cover 100 and is used to irradiate the material to be tested in the curing cavity 101; and a displacement sensor, which is located inside the non-transparent cover 100 and is used to collect the polymerization shrinkage rate of the material to be tested.

[0043] The polymerization shrinkage rate testing device provided by this utility model includes a non-opaque cover 100 with a curing chamber 101 for filling the material to be tested; a photocuring machine located outside the non-opaque cover 100 for irradiating the material to be tested inside the curing chamber 101; and a displacement sensor located inside the non-opaque cover 100 for collecting the polymerization shrinkage rate of the material to be tested. Thus, the non-opaque cover 100 completely isolates external light, ensuring that only the light source of the photocuring machine triggers the material curing, avoiding unexpected polymerization reactions caused by ambient light, and solving the problem of light leakage that still exists in traditional yellow light or ordinary light shields, leading to measurement deviations in shrinkage rate. The displacement sensor monitors the micron-level thickness change during the material curing process in real time, far exceeding the accuracy of traditional mechanical measuring tools, thus solving the problem that traditional methods cannot capture transient shrinkage behavior and that manual readings have large errors. The polymerization shrinkage rate testing device only requires a few modular components: the non-opaque cover 100, the photocuring machine, and the displacement sensor, making it easy to assemble and reuse. The design of the curing chamber 101 ensures uniform filling of the material to be tested, avoiding measurement errors caused by structural complexity. Therefore, by coordinating the design of the opaque cover 100 and the displacement sensor, the two major challenges of light shielding and high-precision measurement can be solved simultaneously in a single device.

[0044] In the polymerization shrinkage rate testing device provided by this utility model, the displacement sensor is a laser displacement sensor.

[0045] Preferably, the non-transparent cover 100 is made of anodized 7075 aluminum.

[0046] Furthermore, the non-transparent cover 100 includes a top plate 110, side plates 120, and a front plate 130. The side plates 120 are connected to opposite sides of the top plate 110, and the front plate 130 is connected to the top plate 110 and between the side plates 120. The top plate 110, front plate 130, and side plates 120 enclose a curing cavity 101. The enclosed structure of the top plate 110, front plate 130, and side plates 120 forms a closed curing cavity 101, thereby avoiding stray light interference.

[0047] Furthermore, the top plate 110 is integrally connected to the side plate 120, and the top plate 110 is integrally connected to the front plate 130, that is, the opaque cover 100 is a one-piece molded structural component. By making the opaque cover 100 an integral molded structure, deformation caused by vibration or movement can be avoided.

[0048] In addition, the non-transparent cover 100 also includes: a back plate 140 connected to the top plate 110, the back plate 140 being disposed opposite to the front plate 130, one end of the back plate 140 being connected to a side plate 120, and the other end of the back plate 140 being connected to another side plate 120. The side plate 120, the front plate 130, the other side plate 120, and the back plate 140 are sequentially connected to the same side of the top plate 110 and enclose a curing cavity 101.

[0049] Furthermore, the top plate 110 includes a first side 111, a second side 112, and a third side 113; the first side 111 and the second side 112 are arranged opposite to each other; the third side 113 is connected between the first side 111 and the second side 112; the two side plates 120 are disposed on the first side 111 and the second side 112, and the front plate 130 is disposed on the third side 113. The geometric design of the curing chamber 101 ensures that the light source uniformly covers the surface of the material to be tested, reducing the measurement error of shrinkage rate caused by uneven illumination.

[0050] Furthermore, the side panel 120 extends along the first direction Z from the first side edge 111 or the second side edge 112 toward the side opposite to the top panel 110, forming a first height H1, that is, the height of the side panel 120 along the first direction Z is the first height H1. The front panel 130 extends along the first direction Z from the third side edge 113 toward the side opposite to the top panel 110, forming a second height H2, that is, the height of the front panel 130 along the first direction Z is the second height H2, and the first height H1 is equal to the second height H2. In other words, the front panel 130 and the side panel 120 are at the same height. Furthermore, the back panel 140, the front panel 130, and the side panel 120 are at the same height. Moreover, the distance between the end of the side panel 120 away from the top panel 110 and the top panel 130 is the first height H1, and the distance between the end of the front panel 130 away from the top panel 110 and the top panel 130 is the second height H2; the first direction Z is perpendicular to the extension direction of the top panel 110. Preferably, the opaque cover 100 is a rectangular black opaque cover. By ensuring that the side plate 120 and the front plate 130 are at the same height, the internal dimensions of the curing chamber 101 are consistent, making the test results of different batches comparable. The stable cavity structure of the curing chamber 101 ensures the accuracy of the displacement sensor data.

[0051] Furthermore, the top plate 110 has a first reserved hole 114 that penetrates the top plate 110. The UV curing machine is used to irradiate the material to be tested in the curing chamber 101 through the first reserved hole 114. The first reserved hole 114 is a circular hole and serves as a reserved window for irradiation by the UV curing machine. The design of the first reserved hole 114 allows for precise control of the irradiation path of the UV curing machine.

[0052] Furthermore, the front panel 130 has reserved slots 131, with two reserved slots 131 spaced apart and extending through the front panel 130. The reserved slots 131 are used to display the readings of the displacement sensor. The reserved slots 131 ensure light shielding while also taking into account the convenience of human-machine interaction.

[0053] Furthermore, a reserved groove 131 is formed by recessing the front plate 130 from the side away from the top plate 110 toward the interior of the front plate 130. The reserved groove 131 is a cuboid groove, which is used to facilitate the reading of the displacement sensor.

[0054] Furthermore, the side plate 120 has a second reserved hole 121, which extends through the side plate 120. The second reserved hole 121 is used for the power line of the displacement sensor to pass through. The second reserved hole 121 serves as a power line hole for the displacement sensor and facilitates the connection of the power line of the displacement sensor to the power supply. The DC power source is 24V.

[0055] Furthermore, the polymerization shrinkage rate testing apparatus also includes a matte coating (not shown) disposed on the inner circumferential surface of the opaque housing 100. The matte coating serves as the lining of the opaque housing 100, i.e., the anodized 7075 aluminum structure. Through the enclosing structure of the opaque housing 100 combined with the matte coating, complete light blocking is achieved. Thus, this polymerization shrinkage rate testing apparatus can create an "optically inert" environment, ensuring that the polymerization shrinkage of dental materials is triggered only by the curing light source provided by the experimentally designed light-curing machine, such as a blue light curing lamp, rather than by ambient light, thereby improving the testing accuracy of the polymerization shrinkage rate testing apparatus.

[0056] Therefore, the polymerization shrinkage rate testing device provided by this utility model can be used to replace the yellow light chamber when evaluating the polymerization shrinkage rate of dental polymer-based restorative materials, so as to play a role in blocking light. The opaque housing 100 is made of anodized 7075 aluminum with a matte coating to provide light shielding. The opaque housing 100 is a rectangular black opaque housing. A first pre-drilled hole 114 in the top plate 110 serves as the illumination window for the light-curing machine. Two pre-drilled slots 131 (two rectangular slots) in the front plate 130 facilitate readings by the displacement sensor. Second pre-drilled holes 121 in each of the side plates 120 serve as power cable holes for the displacement sensor, allowing for easy connection of the power cable. The power supply is preferably a 24V DC source. This creates an "optically inert" environment for the opaque housing 100, ensuring that the polymerization shrinkage of the dental material is triggered only by the experimentally designed curing light source, such as a blue light curing lamp, and not by unexpected light from the ambient light. This ensures that the polymerization shrinkage of the dental material is generated by the energy output from the light source of the light-curing machine, thereby improving the accuracy of the polymerization shrinkage rate test.

[0057] Based on the polymerization shrinkage testing device provided by this utility model, the polymerization shrinkage testing method includes the following steps:

[0058] Step 100: Place the material to be tested at room temperature for at least 30 minutes; confirm that the laser beam is aligned with the center of the measuring end face of the curing chamber 101;

[0059] In this step 100, an environment with a room temperature of 21℃~25℃ and a relative humidity of 30%~80% is selected as the test environment.

[0060] In step 100, the above-mentioned polymerization shrinkage test device is covered over the entire test device, then the displacement sensor is turned on, preheating for 1 hour, and the test begins after the overall system is basically stable.

[0061] In step 100, the material to be tested is placed at room temperature (21°C to 25°C) for at least 30 minutes; confirm that the laser beam of the displacement sensor is aligned with the center of the measuring end face of the curing chamber 101.

[0062] Step 100 is used as a condition for conducting polymerization shrinkage tests using a polymerization shrinkage testing apparatus.

[0063] Step 200: Apply a small amount of silicone grease to the inner surface of the curing chamber 101, and place the aluminum film on the removable curing chamber wall at both measuring ends of the curing chamber 101.

[0064] This step 200 also includes cleaning and assembling the curing chamber 101; the aluminum film is preferably a thin aluminum sheet or aluminum foil.

[0065] Step 300: When the material to be tested is a polymer-based repair material, it is first filled into the curing cavity 101. After filling is completed, the walls of the curing cavity at both measuring ends are removed, and the aluminum film is left on the surface of the measuring end of the polymer-based repair material. The polymer-based repair material is left to stand in the curing cavity 101 for 5 minutes.

[0066] When the material to be tested is a free-flowing polymer-based material, first lay a thin film on the inner side of the two removable curing chamber walls, apply a small amount of silicone grease to the inner surface of the curing chamber 101, place an aluminum film inside the film and make the aluminum film adhere tightly to the film, and remove the curing chamber walls at the two measuring ends; let the free-flowing polymer-based material stand in the curing chamber 101 for 10 minutes.

[0067] In step 300, the film laid on the inner side of the two removable curing chamber walls is a PE film. The film dimensions meet the following requirements: length greater than 10mm and width greater than 6mm.

[0068] This step 300 also includes the following steps:

[0069] Slowly inject a flowable polymer-based material from the center of the curing chamber 101 to both ends to avoid the formation of air bubbles inside.

[0070] After the injected flowable polymer-based material is flush with the upper surface of the curing chamber 101, cover the upper surface of the curing chamber 101 with the films at both ends, ensuring that the film at each end is in contact with the material on the upper surface at least 2 mm along the long axis of the curing chamber 101; remove the curing chamber walls at both measuring ends.

[0071] Step 400: Turn on the data acquisition unit of the displacement sensor and observe the displayed value. When the displayed value changes by less than or equal to 0.0001 mm within a 30-second time range, record the values ​​L from both displacement sensors. A1 and L B1 Set to zero;

[0072] Step 500: Turn on the UV curing machine and use the UV curing machine to irradiate the material to be tested in the curing chamber 101 through the first reserved hole 114;

[0073] In this step 500, the polymer-based repair material in the curing chamber 101 is irradiated through the first reserved hole 114, i.e., the reserved window of the light curing machine, according to the irradiation time specified in the product manual of the polymer-based repair material.

[0074] Step 600: Starting from the start of the UV curing machine, collect data for 5 minutes, read the data from the displacement sensor, and record it as L. A2 and L B2 ; Calculate the linear polymerization shrinkage rate:

[0075] S = [(L A2 -L A1-L B2 -L B1 ) / 6]*100%;

[0076] In the above formula:

[0077] S—linear polymerization shrinkage rate;

[0078] L A2 —The final data collected by displacement sensor A, in millimeters (mm);

[0079] L A1 —The initial data collected by displacement sensor A, in millimeters (mm);

[0080] L B2 —The final data collected by displacement sensor B, in millimeters (mm);

[0081] L B1 —The initial data collected by displacement sensor B, in millimeters (mm);

[0082] Repeat the above measurement process 10 times, and calculate the average and standard deviation of the linear polymerization shrinkage rate.

[0083] In this polymerization shrinkage rate testing device, the opaque cover 100 completely isolates external light, ensuring that only the light source of the UV curing machine triggers the material curing, thus avoiding unexpected polymerization reactions caused by ambient light. A displacement sensor monitors the micron-level thickness changes during the material curing process in real time, far exceeding the accuracy of traditional mechanical measuring tools. The polymerization shrinkage rate testing device requires only the opaque cover 100, the UV curing machine, and the displacement sensor modular components, making it easy to assemble and reuse. The curing chamber 101 is designed to ensure uniform filling of the test material, avoiding measurement errors caused by structural complexity. Therefore, through the collaborative design of the opaque cover 100 and the displacement sensor, the two major challenges of light shielding and high-precision measurement are simultaneously solved in a single device.

[0084] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A polymerization shrinkage rate testing device, characterized in that, include: The non-transparent cover has a curing chamber for filling the material to be tested. A photocuring machine is installed outside the non-transparent cover and is used to irradiate the test material inside the curing chamber; A displacement sensor, disposed within the opaque cover, is used to collect the polymerization shrinkage rate of the material under test.

2. The polymerization shrinkage rate testing device as described in claim 1, characterized in that, The non-transparent cover includes: a top plate, a front plate, and side plates; wherein... The side panels are connected to opposite sides of the top panel; the front panel is connected to the top panel, and the front panel is connected between the two side panels; and, The top plate, the front plate, and the two side plates together form the curing cavity.

3. The polymerization shrinkage rate testing device as described in claim 2, characterized in that, The top plate includes: The first and second sides are set relative to each other; The third side connects the first side and the second side; wherein... The two side panels are respectively disposed on the first side and the second side; the front panel is disposed on the third side.

4. The polymerization shrinkage rate testing device as described in claim 3, characterized in that, The side plate extends along a first direction from the first side or the second side toward the side opposite to the top plate, forming a first height; The front plate extends along the first direction from the third side toward the side opposite to the top plate, forming a second height; wherein, The first height is equal to the second height; The first direction is perpendicular to the extension direction of the top plate.

5. The polymerization shrinkage rate testing device as described in claim 1, characterized in that, Also includes: A matte coating is applied to the entire inner circumferential surface of the curing cavity.

6. The polymerization shrinkage rate testing device as described in claim 2, characterized in that, The top plate has a first reserved hole that penetrates through the top plate. The light curing machine is used to irradiate the material to be tested in the curing chamber through the first reserved hole.

7. The polymerization shrinkage rate testing device as described in claim 2, characterized in that, The front panel has a reserved slot, and two reserved slots are spaced apart and pass through the front panel. The reserved slot is used to display the reading of the displacement sensor.

8. The polymerization shrinkage rate testing device as described in claim 7, characterized in that, The reserved groove is formed by a recess in the front plate from the side away from the top plate toward the interior of the front plate.

9. The polymerization shrinkage rate testing device as described in claim 2, characterized in that, The side plate has a second reserved hole, which extends through the side plate and is used to allow the power line of the displacement sensor to pass through.

10. The polymerization shrinkage rate testing device as described in claim 2, characterized in that, The top plate is integrally connected to the side plate, and the top plate is integrally connected to the front plate.

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