Some standard content:
Article 5.1.2 of this standard is recommended, and the rest are mandatory. YY0460—2003
The consistency of this standard with IEC61205:1993 "Ultrasonic - Dental Descaling System - Measurement and Publication of Output Characteristics" is modified and adopted. The main contents of the modification include: 1. Standard title
The three-part structure adopted in the original standard title actually includes the normative technical elements of my country's product standards - requirements and test methods, and the training method of "dental descaling system" does not conform to the medical device habits of my country, so it is renamed "ultrasonic tooth cleaning equipment". 2. Changes to relevant chapters
According to GB/T1.1-2000 and GB/T1.2-2002, this standard merges "5 General measurement conditions" and "6 Measurement steps" in IEC61205 into "6 Test methods". "7 Requirements for publication of basic output characteristics" is changed to "5 Requirements", and the contents of safety, environmental testing and appearance are added.
According to the requirements of the compilation of product standards in my country, this standard also adds "7 Inspection rules" and "8 Marking, packaging" two chapters. In addition to the above changes, IEC All contents of 61205 are adopted in this standard. Appendix C of this standard is a normative appendix, and Appendix A, Appendix B and Appendix D are all informative appendices. This standard is proposed by the State Food and Drug Administration. This standard is under the jurisdiction of the National Medical Ultrasonic Equipment Standardization Technical Committee. This standard was drafted by the National Medical Ultrasonic Equipment Quality Supervision and Inspection Center and Shantou Jinqiao Medical Equipment Co., Ltd. The main drafters of this standard are: Mang Anshi, Wang Zhijian, Jiang Yuren, and Jiang Songxuan. I
1 Scope
Ultrasonic Tooth Cleaning Equipment
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This standard specifies the terms and definitions, symbols, requirements, test methods, inspection rules and markings, and accompanying documents for ultrasonic tooth cleaning equipment. This standard applies to ultrasonic tooth cleaning equipment (hereinafter referred to as equipment) that generates continuous or quasi-continuous wave ultrasonic energy by ultrasonic transducers in the frequency range of 18kHz to 60kHz. 2 Normative references
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated references, all subsequent amendments (excluding errata) or revisions All of them are not applicable to this standard. However, parties to an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For any undated referenced document, the latest version applies to this standard GB9706.1-1995 Medical electrical equipment Part: General safety requirements (idtIEC60601-1: 1988) GB/T14710 Environmental requirements and test methods for medical electrical equipment 3 Terms and definitions
The following terms and definitions apply to this standard. 3.1
Half-excursion force half-excursion forceThe contact force required between the tip and the slide to reduce the primary tip vibration excursion to 50% when the contact force between the tip and the slide is 0.15N±0.02N.
primarytipvibrationexcursionThe peak-to-peak displacement of the tip in the direction of maximum amplitude at a point no more than 1mm from the tip. 3.3
tip vibration frequency
tip vibration frequency
The fundamental frequency of the tip vibration.
4Symbol
s--Tip primary vibration excursion:
W. —The width of the notch mark on the slide when the power is off; WpThe width of the notch mark on the slide when the power is on. 5 Requirements
5.1 Output characteristics requirements
5.1.1 The manufacturer shall publish the following basic output characteristics that can be achieved for each tip of the equipment: a) The main vibration offset of the tip;
The vibration frequency of the tip;
c) The half-excursion force.
When publishing the above basic output characteristics, the manufacturer shall state its working conditions in the product standards and accompanying documents (see 6.1). YY 0460--2003
5.1.2 The equipment should have the following functions:
The main vibration offset of the tip should be adjustable, and its adjustment range can be reduced to less than 50% of the maximum value; a)
b) The vibration frequency of the tip should be able to be automatically or manually tuned, and the deviation between the operating frequency and the nominal frequency of the handle should not exceed 10%; c) The flushing water pressure or flow should be adjustable from zero to the maximum value. 5.2 Safety requirements
See Appendix C.
5.3 Environmental test requirements
Should comply with GB/T14710, and the climatic test group and mechanical test group to which it belongs should be specified in the enterprise standard. 5.4 Appearance and structure
The appearance should be smooth, without cracks, stains, or obvious deformation, the pipeline seal should not leak, and the operating mechanism should be flexible and reliable. 6 Test method
6.1 Measurement working conditions
When measuring, the parameters should be set according to the manufacturer's recommendations. The parameters to be considered are as follows: a) ambient temperature;
b) continuous flushing water flow at the tip of the action head;
c) excitation frequency;
d) output amplitude;
e) warm-up time.
Before measuring, the settings of all control ends related to the ultrasonic cleaning device should produce the maximum amplitude. 6.2 Load conditions
During the measurement, the tip of the application head shall be in contact with the microscope slide. The slide shall be lubricated with water (tap water is sufficient), and the contact force shall be 0.15N ± 0.02N. To facilitate the measurement of the semi-deflection force, the load shall be increased step by step (see 6.7). To ensure the accuracy of the measurement, the movement of the tip shall be essentially perpendicular to the load. The force on the tip shall be known or measured. 6.3 Cleaning of the device
All surfaces of the application head (tip) and the measuring device in contact with water shall be cleaned, rinsed with warm water and dried. 6.4 Rinsing temperature
The rinsing temperature shall be between 30℃ and 40℃ or at a temperature specified by the manufacturer (see 5.1.1). 6.5 Tip primary vibration deflection
The tip primary vibration deflection shall be measured by one of the following methods. The accuracy of the vibration deflection measurement shall be better than ±10% at 100μm (see Appendix B for details of the measurement method). The load conditions and the method that meets the requirements of this standard shall be clearly stated in the measurement report. Note: The maximum tip principal vibration excursion is in the region of 100 μm. At a constant excitation frequency, the operator can control the magnitude of the excursion. 6.5.1 Optical microscope method
The microscope is focused on a point on the action head (tip) that is no more than 1 mm away from its tip. After the action head (tip) is excited, the point appears as a line. The relative orientation of the tip and the microscope should be able to be changed to observe the longest line length. The length of the line is equal to the tip principal vibration excursion and should be measured using a calibrated eyepiece ruler or micrometer. If vibrations are generated in other directions at the same time, the motion trajectory of the point on the action head (tip) is an ellipse. The maximum size of the ellipse should be measured and should be taken as the tip principal vibration excursion.
6.5.2 Slide method
According to the provisions of 5.2, the tip of the action head is in contact with the slide. When the device is turned on and off, the slide under the tip of the action head is moved in a U-shaped grating form, and the notch mark is measured to ensure that the trajectory is perpendicular to the direction of maximum tip vibration. The following formula is given to determine the tip main vibration offset s: 2
Wp——the width of the notch mark when the device is turned on; W.——the width of the notch mark when the device is turned off.
6.6 Tip vibration frequency
s =(Wp-Wo)
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One of the following methods should be used to determine the tip vibration frequency. The accuracy of the frequency measurement should be better than ±1%. In some devices, the excitation frequency can be manually controlled by the operator, and the action head (tip) can be adjusted to its resonant frequency so that the tip vibration amplitude is the maximum. The tip vibration frequency should be measured when the manual adjustment frequency control makes the tip vibration offset the maximum. Note: For ultrasonic tooth cleaning equipment, the tip vibration frequency is between 18 kHz and 60 kHz. 6.6.1 Vibrometer method
A non-contact vibrometer (see Appendix B) should be used. The vibration frequency of the tip should be measured using a frequency meter or an oscilloscope capable of calibrating the time base on the output of the vibrometer.
6.6.2 Frequency meter method
A frequency meter should be used to measure the frequency of the excitation voltage on the application head (tip). 6.7 Half-deflection force
During the step of determining the main vibration deflection of the tip (see 6.5.1 or 6.5.2), the force applied by the tip to the microscope slide should be increased until the main vibration deflection of the tip is reduced to half of the value when the contact force is 0.15N±0.02N (see Appendix B), and the force is measured. Note: When the force on the tip of the application head increases, the main vibration deflection of the tip decreases. Reduce the deflection to the standard load condition (0.15N±0.02N).02N) is an indicator of the effective working energy of the equipment. 6.8 Safety
For test methods, see Appendix C.
6.9 Environmental test
Perform according to the procedures specified in GB/T14710.
6.10 Appearance and structure
Inspect by visual inspection and operation.
7 Inspection rules
Acceptance of safety performance
For the acceptance rules of equipment safety performance, see Appendix C. 7.2 Inspection classification
Equipment must be submitted for acceptance in batches, and the inspection is divided into factory inspection and type test. 7.3 Factory inspection
7.3.1 Factory inspection is carried out by the technical inspection department of the manufacturer. 7.3.2 Factory inspection should be carried out by random sampling in qualified batches, and the number of samples shall be as specified in Table 1. The inspection items are 5.1.1a) and 5.4. Table Factory Inspection
Number of inspection/unit
>100～200
Percentage of inspection number in batch inspection number/(%)10
Not less than 1 unit
7.3.3 During the inspection process, if any of the main performance items 5.1.1a) do not meet the requirements of this standard, or if two items of other performance do not meet the requirements of this standard, double the number of samples shall be sampled for inspection. If the products still fail to meet the requirements during the re-inspection, the batch of products shall not be accepted. 3
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7.4 Type test
7.4.1 Type test time
Type test should be carried out in one of the following situations: a) before new products are put into production (including old products transferred to the factory for production); b) in normal production, at least once a year; when production is resumed after a long-term shutdown;
when there are major changes in design process or materials that may cause changes in equipment performance; d)
e) when the national quality supervision department makes a request. 7.4.2 Type test items
are all items specified in this standard.
7.4.3 The number of type test samples
is not less than 2 sets, and should be randomly selected from products that have passed the factory inspection. 7.4.4 Type test qualification judgment
During the type test, if one of the main performance 5.1.1a) fails, or two of the other items fail, the batch of products shall be doubled and retested. If it fails again, the batch of products shall be judged as unqualified. 8 Marking and accompanying documents
8.1 Product marking
Each equipment shall have the following markings in an appropriate and obvious position: manufacturer's name and trademark;
b) product name and model;
registration number;
d) product factory number or production date.
8.2 Packaging marking
a) manufacturer's name and address;
b) product name, model, quantity;
registration number;
d) product manufacturing year and month or production batch number.
8.3 Accompanying documents
When each equipment leaves the factory, the following accompanying documents should be included in the packaging box: a) Packing list, random spare parts, accessories list; b) Certificate of conformity;
Instruction manual;
d) Warranty card.
8.3.1 Certificate of conformity
The certificate of conformity must have the following marks:
a) Manufacturer's name;
b) Product name and model;
c) Inspection date;
d) Inspector code.
8.3.2 Instruction manual
Should be able to guide users to correct operation and maintenance. 4
A.1 Background
Appendix A
(Informative)
Overview of Ultrasonic Dental Scalers
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More than 130,000 ultrasonic scalers are in use, with the primary purpose of removing plaque and calculus from teeth. The device consists of a generator, a handle, and various action heads (tips) that are connected to the handle. The cleaning action produced is believed to be caused by the following actions: the scraping or shearing action caused by the direct contact of the tip with the plaque and calculus; the ultrasonic jet and cavitation generated in the area; and the abrasive action of the removed calculus particles. Widely accepted ultrasonic devices are used based on clinical needs to prevent and treat the widespread prevalence of periodontal disease, which is the main cause of tooth damage in adults over 35 years of age and is an inflammatory process indirectly caused by various pathogens. In the hands of skilled professional dentists, this ultrasonic equipment provides an effective means of treatment for patients in the early to late stages of the disease. Despite its widespread acceptance and use in the treatment of periodontal disease, its mode of action is not well defined, nor are its acoustic parameters clearly described. The ultrasonic frequencies used range from 18,000 Hz to 60,000 Hz. The ultrasonic vibration system is a magnetostrictor or piezoelectric chip, and the action head (tip) is usually excited at a resonant frequency. In some systems, the operator can adjust the frequency of the vibration system to achieve resonance, at which time the spray effect of the irrigation water flow is maximized. In other devices, the frequency is automatically controlled by the device. There are several shapes of descaling action heads (tips). Most action heads (tips) have a short curved head behind the matching handle, which converts the longitudinal vibration of the vibration system into an elliptical motion of the tip of the action head (tip).
The efficiency of this type of device is not 100%, so it will generate heat, especially the magnetostrictive type. In order to dissipate heat, including the friction heat generated by the action of the tip and the tooth surface, a liquid irrigation flow is usually used from the handle to the contact point between the tip and the tooth surface. The liquid is usually water, sometimes saline, and the temperature of the irrigation can be controlled by adjusting the water flow. The water flow is usually adjusted to a temperature slightly below oral temperature. Irrigation can also produce other beneficial effects, including lubrication, cleaning, and cavitation. Cavitation is an important aspect of scale removal. To avoid injury to the patient, the use of the device requires skill training. In practice, the operator is required to use a light contact (0.15N). The vibration of the tip helps to remove plaque and calculus. The cavitation effect caused by the tip vibration may be mainly responsible for the removal of surfaces not in direct contact with the tip. The acoustic output produced by the device will vary greatly depending on factors such as operator skill, effective generator power, power setting, tuning, coupling and tip structure. The pressure exerted by the tip on the tooth surface may change the resonance characteristics. Therefore, for optimal removal efficiency, it is required that the amplitude of the tip be adjusted to the resonance point when in contact with the surface.
A.2 Operational Hazards
A.2.1 Thermal Damage
Investigations into the effects of ultrasonic energy have shown that congestion and cell damage can occur under conditions of prolonged application or high power. Normally, patients cannot tolerate heat applied to their teeth, but in cases of nerve damage or under the effects of anesthetics, care must be taken to avoid overheating and thermal damage to the teeth. Magnetostrictors also generate heat. In such devices, interruption of the cooling water flow may cause a jet of heated water during the subsequent resumption of irrigation, which may cause discomfort to the patient.
A.2.2 Mechanical damage
In the normal use of dental instruments, mechanical damage due to sound is not expected. In the treatment of periodontal disease, it may be necessary to perform various manipulations of the gingival tissue. For example, plaque may be removed from the gingival trough, or root planing and scraping may be performed to remove foreign matter from the gingival tissue. For these operations, the healing of the gingival tissue takes 12 to 18 days with conventional dental instruments. When ultrasonic dental devices are used, the healing time is approximately the same. However, some studies have shown that the healing time is slightly shorter when ultrasonic dental devices are used. Studies including scanning electron micrographs have revealed that the removal of scale from the dentin by the tip results in an increase in surface roughness. This result is seen after both conventional dental instruments and ultrasonic scalers. Therefore, care should be taken to avoid unnecessary roughening of exposed surfaces, which should be polished after scaling. Histological studies have shown that the periodontium shows damage to epithelial and connective tissues, and this effect is proportional to the acoustic energy. 5
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However, this damage is similar to the results of scaling of gingival surfaces using ordinary dental instruments. To avoid unnecessary damage to tissue, the minimum energy level and shortest exposure time recommended by the manufacturer should be followed. The scaling effect of ultrasound on tooth surfaces depends mainly on the skill of the user. If the acoustic output and tip pressure are low, the tooth surface will not be damaged. A.2.3 Biological effects of ultrasound
There are only a few literatures on the existence of confirmed biological effects of ultrasonic radiation on scaling tips on soft tissues, and it seems more important to consider other forms of risk sources.
The biological effect is mainly related to the damage to the root surface, including hard tissue. Therefore, ultrasonic descaling devices require skilled skills like any tool in dentistry. There is no evidence to show that ultrasonic devices are more dangerous than other tools used in dentistry. A:3 Rationality of measurement
Like other instruments used in dentistry, ultrasonic dental devices can cause harm to patients if used in an unprofessional manner. The purpose of the measurement methods described in this standard is to advise the operator to operate the device in a manner consistent with known operating practices. Ultrasonic vibrations may cause heating and cavitation of tissues in cooling water. The main hazard presented is heating of pulp tissue due to friction between the vibration of the probe and the tooth surface.
Damage to the gingiva by the application head (tip) will heal within a few days, while overheating of the pulp can cause irreversible damage. Therefore, the amplitude and frequency of vibration, the characteristics of the tip material (hardness and sharpness), the tooth surface and the presence of lubrication are the main factors causing heating caused by vibration of the application head tip.
B.1 Vibration deflection measurement
Appendix B
(Informative Appendix)
Guide to measurement method
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When measuring the vibration deflection, the tip is in contact with the microscope slide. The contact force is adjusted to 0.15 N ± 0.02 N. The slide is lubricated with tap water or saline. The surface of the slide is cleaned with warm water and detergent to remove the oil film. It is rinsed with water and left to air dry for ten minutes. The design of a suitable mechanical fixture is shown in Figures B.1 and B.3.
The handle and its accessories are clamped in a pivot bracket. The cable and flushing pipe are loosely wound on the support. The tip of the application head rests on the slide fixed to the workbench. The weight of the sliding block on the bracket makes the handle just balanced. Then, weights are added at predetermined positions so that the force on the tip is 0.15 N (equal to the gravity of a mass of 15 g). In the configuration shown in Figure B.3, the load can be increased by adding weights until the vibration deflection is 50% of its initial value. For all measurement methods, care should be taken to make the vibration deflection perpendicular to the direction of the load applied to the tip. B.1.1 Optical microscopy method
The core of this method is to observe the vibration of the tip directly by observing the bright spot reflected from the surface of the application head (tip) using a metallographic microscope. A pinhole diaphragm located at the rear focal plane of the condenser is used to produce a light spot whose magnified image is no larger than one-fifth of the vibration amplitude. Assuming a circular light spot, the peak-to-peak deviation is obtained by measuring the peak-to-peak amplitude of the oscillation and subtracting the width of the light spot. The magnification of the microscope is recommended to be at least 100 times, and the calibration scale is in micrometers, with at least 5um as one division, and the full scale is 250μm. The operator fixes the handle of the ultrasonic dental device on the microscope, and the tip contacts the slide with a contact force of 0.15N±0.02N. A pharmaceutical balance or electronic balance can be used to measure the code for applying this force. The surface of the slide is wetted with water. A mechanical stage is used to determine the position of the tip on the slide. The operator moves the slide manually in a "U"-shaped trajectory. The first side of the "U" is obtained when the device is turned on, and the other side of the "U" is obtained when the device is turned off. This allows the operator to directly observe or photograph the tip movement when the device is turned on and off. B.1.2 Glass recording method
The second measurement method uses the same handle clamp and the slide is positioned relative to the tip. The slide is moved on a U-shaped path by a mechanical stage. The path recorded on the glass surface is read by a calibrated microscope. The difference between the two methods is that in the former, the integrated microscope is used for direct observation, while in the latter, only the record is left on the glass and the offset is read later. The slide is clamped on a table with a U-shaped guide groove attached to a fixed base. The guide block protruding from the bottom of the table fits into the groove. The table is moved manually and the slide moves in a "U"-shaped path under the vibrating tip. The base is located in a shallow tray with a drain pipe. This allows the slide to be continuously lubricated with water from the handle flushing pipe (see Figure B.2). For periodic measurements, the slide is divided into several areas and clamped in a new position when necessary. One side of the "U"-shaped path is the trace when there is no vibration, which can be compared with the trace on the other side when it is vibrating. For some devices, the tip is blunt and does not leave a mark on the glass when not stimulated. Before the measurement, wax or carbon is applied to the glass surface to make the track visible. A simple way to apply carbon to the surface of the slide is to pass the slide through the flame of a candle. B.2 Half-deflection force measurement
This measurement requires that the tip (tip) is placed in the working state and the contact force is increased until the main vibration deflection of the tip is reduced to 50% of its initial value under standard load conditions. The test configuration is shown in Figure B.1. The load weight is moved or added, and the half-deflection force is measured by replacing the slide with the balance pan. Another method is to increase the force above the load weight with a compression spring balance. The calculation of the force acting on the tip must take into account the mass of the load and the relative distance of the tip from the pivot. It is important to keep the position of the tip (tip) unchanged for all measurements, so that the angle between the tip (tip) and the slide or balance pan remains unchanged. B.3 Frequency measurement
Non-contact vibrometers may be capacitive or inductive devices that are sensitive to changes in the position of a conductor such as a vibrating dental descaler tip. Details of suitable devices and precautions for use may be found in IEC 60782. Cable support
Microscope slide
Table,
Sink base
Balance weight
Load weight
Microscope slide
Movable table
Layout of microscope slide method
Slide clamp
U-shaped concave
Guide block
Slide clamp
Standard magnetic code
Linear bearing
Microscope
Contact angle adjustment
Figure B.3 Another layout of microscope slide method YY0460-—2003
Handheld part clamp
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C.1 Product Features
Appendix C
(Normative Appendix)
The following safety features of the product should be specified in the enterprise standard: a) the safety type of the equipment and application parts; b) the power supply used by the equipment;
c) the input power of the equipment;
d) the degree of protection against liquid ingress of the equipment and application parts. C.2 Requirements and test methods
C.2.1 External markingswwW.bzxz.Net
There should be at least the following "permanently affixed" and "clearly recognizable" markings: a) the name of the enterprise and the trademark (or name) of the instrument; b) the instrument model;
c) connection to the power supply;
d) safety classification.
Test method: in accordance with the test method specified in 6.1 of GB9706.1--1995. C.2.2 Internal markings
The following "permanently affixed" and "clearly legible" markings shall be provided: a) If there is a battery, the model and installation method shall be marked; b) If there is a fuse that can only be reached by using a tool, the specification shall be marked near the fuse. Test method: According to the provisions of 6.2a) of GB9706.1-1995. C.2.3 Control device and instrument markings
Should comply with the requirements of 6.3 of GB9706.1--1995. Test method: Verify by operation inspection. C.2.4 Symbols
The symbols used for marking in C.2.1~C.2.3 must be consistent with the requirements in Appendix D of GB9706.1-1995. Test method: Verify by inspection. C.2.5 Wire insulation color
Class I equipment using AC mains power supply shall comply with the following requirements: a) The insulation of the protective grounding wire shall be green/yellow throughout its length. The insulation on the wires connected to the protective earth terminal inside the equipment must be green/yellow at least at the wire terminals;
b) The color of the wire insulation in the power cord shall comply with the requirements for the colors of three-core cables in GB9706.1-1995, and the insulation of the wire connected to the neutral wire of the power supply shall be light blue. Test method: Verify by inspection. C.2.6 Gas identification
Not applicable.
C.2.7 Gas connection point identification
Not applicable.
C.2.8 The color of the indicator light
shall comply with the requirements of 6.7a) in GB9706.1-1995. Test method: Verify by inspection. C.2.9 The color of the button
shall comply with the requirements of 6.7b) in GB9706.1-1995. Test method: Verify by inspection. C.2.10 The completeness of the random documents
should comply with the provisions of 6.8.1 of GB9706.1--1995. Test method: Verify by inspection. C.2.11 The instruction manual
should include the contents specified in 6.8.2a), c) and d) of GB9706.1-1995. Test method: Verify by consulting the instruction manual. C.2.12 The technical specification
should include the following contents:
a) GB9706.1-1995 6.8.3 a), b), d) specified in b) The enterprise may provide the commitment of the documents listed in 6.8.3 c) of GB9706.1-1995 upon request. The technical specification may be combined with the instruction manual. Test method: Verify by checking. C.2.13 Input power
Equipment using AC power supply shall comply with the provisions of 7.1 of GB9706.1-1995. Test method: According to the method specified in 7.1 of GB9706.1-1995. C.2.14 Environmental test
C.2.14.1 Transportation and storage: shall comply with the provisions of 10.1 of GB9706.1-1995. C.2.14.2 Operation: shall comply with the provisions of 10.2 of GB9706.1-1995. C.2.14.3 Test method: Verify by inspection and relevant tests. C.2.15 Safety type
Shall comply with the provisions of Chapter 14 of GB9706.1-1995. Test method: Verify through inspection and relevant tests. C.2.16 Residual voltage
Equipment using AC power supply shall comply with the requirements of 15b) of GB9706.1-1995. Test method: Test with a residual voltage tester in accordance with the provisions of 15b) of GB9706.1-1995. C.2.17 Residual energy
Not applicable.
C.2.18 Enclosure of the enclosure
Shall comply with the provisions of 16a) of GB9706.1-1995. Test method: Test with a standard test finger, a test needle, and a straight test finger. C.2.19 The safety of covers and doors that can be opened without tools shall comply with the requirements of 16a) 5) of GB9706.1-1995. Test method: Use standard test finger, test needle and straight test finger to test. C.2.20 Safety of lamp
Not applicable.
C.2.21 Safety of cover
Should meet the requirements of 16b) of GB9706.1-1995. YY 0460---2003
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