WO2025196476A1 - Dental material surface treatment system: sterilization, surface evaluation, and hardness measurement capabilities - Google Patents

Abstract

The apparatus for surface treatment and machining of dental materials boasts three perpendicular axis movement platforms, a dental handpiece holder or machining means, a gripper platform for securing dental material samples, a cooling system, and a controller unit ensuring repeatable functionality. This innovative method combines surface treatment with machining, ensuring consistent application of force onto material samples. Enhanced with an ultrasonic bath for sample cleaning, integrated UV lamps for chamber disinfection, a profilometer probe for surface roughness measurement, and a Vickers hardness test for material hardness assessment, this device sets a new standard for precision and efficiency in dental material processing.

Description

Description

Title of Invention : Dental Material Surface Treatment System: Sterilization, Surface Evaluation, and Hardness Measurement Capabilities

Technical Field

[0001] This invention pertains to dentistry, surface treatment and machining on dental materials, performing experiments on dental materials.

Summary of Invention

[0002] On the basis of this invention, an apparatus is provided for the surface treatment and machining of dental materials comprising three perpendicular axis movement platforms, holder of dental handpieces or the means for machining, a gripper platform for holding samples of dental material, a cooling system for samples and a controller unit, whereby the controller unit enables the apparatus function to be repeatable.

[0003] This invention provides a method for the surface treatment, while the machining of dental materials is characterized by the fact that the application of force from dental hand pieces or means for machining onto the materials sample is time-constant and repeatable.

Technical Problem

[0004] Conventionally, surface treatment and machining on dental materials are done manually both in the field and laboratories except for the CAD/CAM technology, in which case a simple process can consume a fair amount of time and is not practical to deploy.

Solution to Problem

[0005] Up to this date, various materials have been introduced in the field of dentistry to supply favorable properties. These materials undergo grinding, polishing, and different surface treatments in clinical circumstances; therefore, several studies in the field of dental materials have evaluated the effects of mentioned procedures on different properties of those materials. Numerous factors such as pressure, temperature, duration, and surface topography can modify the effects of a surface treatment on a dental material, resulting in a differentiable surface roughness, which is highly important. Some researchers have so far been trying to provide repeatability for experiments through different means such as employing human senses, performing the treatments by the same operator, using mechanical mechanisms and sensors to sight alternations during the study.

[0006] The aim of this invention, The method and apparatus for the unification of surface treatment and machining on dental materials conditions, considering the vast number of materials used in dentistry, frequent introduction of new materials, numerous devices required in dental experiments, the need for assessing and evaluating the materials and devices, and the increasing demand for these experiments, is to provide familiar conditions for studying materials in dental research, which can play a key role in using, improving, and introducing new dental materials. In addition, this device can contribute to the indirect fabrication of temporary crowns by preparing chosen teeth of the casts with no undercuts. Moreover, the finishing line can be prepared precisely. On the other hand, the primary and best-known means for the fabrication of temporary crowns are direct, indirect, and direct-indirect approaches, all of which have their own disadvantages.

[0007] The main innovation of this device is that it can standardize experimental conditions for the study of different dental materials, which are conducted using a range of different dental tools and handpieces. As an innovation, high-speed handpiece, low-speed handpiece, and straight handpiece can be employed in this device. Moreover, all types and designs of dental burs can be employed in this device. All types of dental materials in any measure can be treated by burs in the invention. In addition, the device can standardize surface treatments in terms of the temperature of the specimens during treatment, duration of the treatment, surface roughness and topography.

[0008] The method for the unification of surface treatment and machining on dental materials conditions and apparatus for performing this method is designed for both experimental and clinical use; therefore, it needs to be robust, reliable and precise. [0009] This method and apparatus for performing this method comprise four major sections:

[0010] 1- Movement and motion and power transmission

[0011] 2- Holder and gripper of tools and samples

[0012] 3- Micro unit (dental tools driver), compressor and cooling system

[0013] 4- Controller unit

[0014] The details for the sections named above are as follows:

[0015] • Movement and motion and power transmission section:

[0016] One of the vital purposes of this method and apparatus for performing this method is precision and accuracy in the movement with nearly null backlash to be done as robustly as possible.

[0017] This part comprises three movement platforms (1 , 2, 3) in three directions of vertical axis (Z), longitudinal axis (X) and transverse axis (Y). By looking at the movement platform of the transverse axis (3), it can be noticed that there is a stepper motor (10) for providing the power for transmission through the lead screws (11 ) to initiate a motion in that axis.

[0018] The actuator or power provider for the motion here is preferably stepper motor chosen for its precision and torque, but there are many actuators like servo motors or any other controllable electrically powered motor that can be used for this part, as well.

[0019] As a result, for the motion itself, the actuator spins the leadscrew and by spinning in the screw holes of the platform motion, changes from circular into linear in the direction of the said axis. Moreover, there are guiding shafts (11 ) for spreading the weight of the platform and helping the leadscrews to do their job perfectly.

[0020] Other movement platforms are accorded the same conditions with few adjustments in their size and length.

[0021] Also, the movement in the vertical axis (Z) is monitored by a laser or optical sensor (9), which is placed on the upper part (roof) of the apparatus, facing down to control the placement of the contacted surface and height changes of samples during machining.

[0022] The said movements can be determined both manually by the operator, using the LCD touchscreen (6) as the user interface or automatically and predetermined with the command of the controller unit. Under the latter circumstance, the operator sets the origin placements, offsets and conditionally chooses the preprogrammed types of the movements.

[0023] • Holder and gripper of tools and samples section:

[0024] This section comprises a tool holder (4) and a gripper and sample holder (8).

[0025] The tool holder (4) comprises a universal joint (4.1 ) to adjust the tool holder into any shape or angle required by the user, a tool holder clamp (4.2) with the ability to adjust the size of itself with screws (by opening and closing) to hold a variation of tools, a spring and damper (4.3) part for controllable variables which can result into constantly applying force in confronting any uncertainty in the system or variables of the experiment and an In Line Load Cell sensor (4.4) in order to control the force and give feedback to the controller unit (which will be discussed later).

[0026] This part is meant to hold dental tools like handpieces or turbines or means for machining in a variation of sizes and angles. The tools will be held by the clamps whose sizes can be adjusted with the screws and whose angles can be adjusted in accordance with the universal joints that they are fixed to. The universal joints are fixed in a predetermined height on the vertical axis (Z) and their fixed end cannot move.

[0027] The spring and damper part is fixed on the top of each clamp from one end and is connected to the inline load cell sensor from the other end and the sensor is fixed to the upper part (roof) of the apparatus.

[0028] There can be more than two clamps in this section.

[0029] The gripper and sample holder (8) comprises a two-point sample holder mechanism and a temperature sensor (8.1 ) for parts and samples. The two-point sample holder mechanism is fixed on the platform for moving in the direction of the transverse axis (3) and the temperature sensor is fixed on one of the clamps or grippers of the two-point sample holder, and naturally for the sensor to perform well and give correct feedback to the controller unit, the material used in the two- point sample holder clamps or grippers needs to be heat conductible.

[0030] The sample holder is modular and can be replaced by another sample holder which have two or three degrees of freedom, turning the whole apparatus into a five- or six-axis movement platform, which can be used for much complicated samples like a single teeth model.

[0031] • Micro unit (dental tools driver), compressor and cooling system section:

[0032] There is a built-in micro unit (5) which has a compressor. The micro unit works as a driver for dental tools like handpieces and turbines, etc., and this means there is no need to have a whole dental unit for experiments in the laboratories which consume a lot of space.

[0033] Also, the compressor of the micro units can be used as a source of blowing air through cooling system pipes and nozzle (7) for removing chips off the samples during the procedure or machining.

[0034] The cooling system includes separate pumps for applying cooling fluids onto the samples during the procedure or machining, both manually through the user interface (6) or automatically by the controller unit, which enables the processing of the given feedbacks from the temperature sensor (8.1 ).

Description of Embodiments

[0035] FIG. 1 shows 3D view of the apparatus including:

[0036] 1 : illustrates a platform or mechanism for movement in the direction of the vertical axis (Z)

[0037] 2: illustrates a platform or mechanism for movement in the direction of the longitudinal axis (X)

[0038] 3: illustrates a platform or mechanism for movement in the direction of the transverse axis (Y)

[0039] 4: illustrates a tool holder as a versatile rake mechanism, with the components provided in Fig. 2. [0040] 5: illustrates a micro unit for setting up dental tools (turbines, handpieces, etc.) and cooling fluid tank and pump with the electrical part and circuit of the controller unit

[0041] 6: illustrates a LCD touch screen as the user interface of the apparatus and a controller unit

[0042] FIG. 2 shows the holder of dental handpieces mechanism including:

[0043] 4-1 : illustrates a universal joint to adjust any shape and angle required by the user

[0044] 4-2: illustrates tool holder clamp with the ability to adjust the size with screws

[0045] 4-3 illustrates spring and damper

[0046] 4-4 illustrates in Line Load Cell sensor in order to control the force

[0047] FIG. 3 shows the view of upper part of apparatus including:

[0048] 7: illustrates a coolant tube and nozzle of samples with the ability to change the direction and shape and adjust the position of the contact surface

[0049] 9: illustrates a laser or optical sensor to control the placement of the contacted surface and height changes of samples during machining

[0050] FIG. 4 shows a gripper platform for holding samples of dental material including:

[0051] 8: illustrates a gripper and sample holder with automatic movable jaws

[0052] 8-1 : illustrates a temperature sensor for parts and samples

[0053] 10 illustrates a stepper motor (actuator) to provide the power for transmission through the leadscrews

[0054] 11 : illustrates a leadscrew and guide shaft for motion and power transmission in all axis movements

[0055] FIG. 5 shows the closed body of the apparatus including:

[0056] 12: Illustrates a frame cap for the apparatus.

Claims

Claims

[Claim 1] 1- Ultrasonic bath utilizes ultrasonic waves to generate microscopic bubbles in a cleaning solution. These bubbles burst while they come into contact with surfaces, effectively dislodging debris and contaminants. This process is particularly beneficial for surfaces that are difficult to access, such as narrow grooves or irregular surfaces. Ultrasonic baths can enhance the cleanliness and sterilization of dental materials, improving the quality of subsequent processes.

- Residual debris on surfaces can interfere with the bonding process and weaken bond strength. Utilizing an ultrasonic bath to eliminate debris aids in creating a better bond with other materials.

- Surface processing of dental materials generates residual debris and contaminants on the surface, which can alter surface properties such as chemical composition and surface roughness of dental materials. This issue is resolved by employing an ultrasonic bath.

- Debris and contaminants can hinder proper adhesion between materials and lead to separation or fracture of dental restorations. Utilizing an ultrasonic bath prevents this issue.

- Residual debris and contaminants on the surface can affect the accuracy of optical property evaluations of materials. If subsequent stages involve optical property evaluations, an ultrasonic bath will assist in ensuring the accuracy of the next steps.

Considering the aforementioned points, the utilization of an ultrasonic bath, which removes surface debris and contaminants, significantly enhances the accuracy and precision of subsequent stages. Therefore, a compactsized ultrasonic bath has been employed in this device to effectively remove debris and contaminants from the surface. The duration of samples remaining in this bath, as well as the temperature of the solution inside it, can be determined by the user.

[Claim 2] 2- In the field of dentistry, ultraviolet (UV) light is utilized to kill or deactivate microorganisms such as bacteria, viruses, and fungi. UV light is divided into three categories based on wavelength: UV-A, UV-B, and UV-C. Ultraviolet C (UV-C) light, especially within the wavelength range of 200 to 280 nanometers, can damage the DNA and RNA of microorganisms, preventing their replication and eliminating them. Therefore, it is highly beneficial for germicidal purposes.

Sterilization using ultraviolet (UV) light typically involves the use of special UV lamps that emit UV-C light. Surfaces requiring sterilization are typically exposed to UV light for a specific duration, ranging from several minutes to several hours. In this device, UV lamps are installed in the inner body of the apparatus and can be turned on as needed by the user. Additionally, the duration of material disinfection using a timer is adjustable. To prevent user exposure to UV light, a remote control is provided to remotely deactivate the UV lamps. It is important to note that direct exposure to UV light can cause skin and eye damage. Therefore, to ensure safety and prevent direct exposure of the skin and eyes to UV radiation, a UV light- insulated cover is included, which covers the outer body of the device when the UV lamp is activated

[Claim 3] 3- A profilometer is a device that quantitatively measures the surface roughness of an object using a stylus. The stylus moves across the surface of the sample and reports changes in surface height. Before measuring surface roughness, any debris and contaminants must be removed from the surface. The ultrasonic bath present in the device facilitates this cleaning process.

Various parameters such as Ra (average roughness), Rz (maximum peak-to-valley height), and Rq (root mean square roughness) are commonly used to determine surface roughness. Appropriate parameters should be selected for each test based on specific requirements. The profilometer in the device provides the user with the option to select different parameters. The profilometer stylus comes into contact with the surface of the object and moves along the surface profile. During movement, the profilometer records changes in height along the surface and generates the surface roughness profile. After completing the measurement, the data collected by the profilometer is analyzed to determine the desired surface roughness parameters.

Additionally, the user of the device can choose the number of points on the surface where surface roughness is measured. To ensure the accuracy of the test, the user can request measurement at a higher number of points and use the reported average surface roughness.

[Claim 4] 4-The Vickers hardness test is a method for measuring the hardness of materials commonly used in the field of dental materials. This test serves as an essential tool in dentistry for evaluating the mechanical properties of dental materials, ensuring their quality and performance in various clinical applications. In this test, a diamond indenter is pressed into the surface of the material. A small-sized hardness test device is used in this apparatus.

To prevent material damage, the applied force to the samples is determined before applying force to ensure that it falls within the range of forces encountered intraorally. Additionally, the frequency of measurements is determined by the user. This test is utilized for the following purposes:

- Material Hardness Evaluation: The Vickers hardness test can be employed to assess the hardness of dental materials such as dental ceramics, composites, metals, and alloys. This method allows for the determination of material suitability for various dental applications such as dental restorations, veneers, dental bridges, and implants.

- The Vickers hardness test is also utilized as part of quality control processes in dental laboratories and production units. By measuring material hardness, manufacturers can evaluate the uniformity of material properties and identify any defects or inconsistencies that may impact the performance of dental products. - The Vickers hardness test provides the ability to compare hardness values among different dental materials. Dentists and dental researchers utilize this information to select more suitable materials for specific clinical applications based on hardness, durability, and other mechanical properties.

- Hardness testing can offer valuable insights into the wear resistance of dental materials when subjected to chewing pressures and other mechanical forces within the oral cavity. Materials with higher hardness values tend to exhibit greater resistance to wear and other forms of abrasion, making them suitable for long-term clinical use.