How to judge the quality of dental high-speed handpiece？
What are the indicators for judging the pros and cons of dental handpieces? This is what we must first understand. The main factors that determine the performance of dental handpieces are the following:
1. The service life of the handpiece mainly depends on:
correct cleaning and maintenance; bearing material and manufacturing process; internal pipeline material and production of the handpiece. The bearing is a precision part of the turbine handpiece. Clinicians know that it is a vulnerable part. If the cleaning and maintenance methods are not correct, it will easily cause damage to the handpiece. Most of the traditional handpiece bearings are made of steel, and the general movement is composed of outer ring, inner ring, cage and ball. Ceramic ball bearings are mostly used now. Ceramic ball bearings mainly have the following advantages:
(1) High hardness, Ceramic materials are 20% harder than stainless steel materials.
(2) Light weight, The weight of ceramic materials are about 1/2 lighter than that of stainless steel. The friction between the bearing contact surface and the bur barrel is reduced.
(3) Durability, more resistant to high temperature and high pressure sterilization than steel ball bearings.
High-quality ceramic bearings should have lower noise and longer service life. Of course, the quality of ceramic bearings on the market is also uneven. Not all ceramic bearings are better than steel balls. You don’t have to follow this rule blindly, but pay more attention to the technical indicators and practical experience of the cutting force, noise, service life and other technical indicators brought by the handpiece to the dentist.
2. The cutting force of the handpiece
The cutting force of the handpiece is closely related to the power of the handpiece, and the related factors include the torque of the handpiece, the air pressure, the selection of the bur and the usage habits, etc.
3. The cooling effect of the handpiece
The commonly used cooling method for handpiece is single-hole spray, and now the most ideal way is 4-hole spray, and the design of the spray holes of handpiece is also very particular. The best effect is that the water mist can evenly cover the entire bur up to the top.
4. The feel of holding
A good dental handpiece has a plasma-coated material and a threaded anti-slip design on the surface, which feels comfortable and is not easy to slip off. The weight of the handpiece is not the lighter the better, but the weight of the handpiece connected to the tubing is evenly distributed, and whether the position of the gravity balance point is appropriate.
5. The safety and stability of treatment
It depends on the clamping force of spindle and the air pressure inside the handpiece. The international standard clamping force is 22N. A good handpiece needs to be higher than this international standard in order to ensure the safety of long-term use.
6. The convenience of preparing molars
The tooth preparation of the posterior teeth is relatively difficult for dentists to operate. The angle design of the head and body of a good handpiece is very convenient for tooth preparation in the posterior tooth area. The perfect angle design allows the handpiece head to have free movement space in the posterior teeth area, which can make the patient feel more comfortable.
7. Dental handpiece’s noise control
The noise of dental hand-piece can increase the patient's fear during dental treatment. In general, the stress caused by noise and under the influence of prolonged periods can be detrimental to human health, especially during intensive working hours. Therefore, the excessive noise of high-speed dental handpieces is also a kind of damage to the health of dentists. Choosing a low-noise handpiece is a good thing for both patients and doctors.
8. Control of cross-infection
The main influencing factors are: the material selection and surface coating of the dental handpiece, the anti-suckback design of the high speed handpiece, whether it can withstand 135-degree sterilization, and whether there is a built-in filter. The surface treatment of the handpiece must be coated, which can withstand high temperature sterilization without rusting, is not easy to be contaminated with dirt, and is easy to clean and disinfect. In the early high speed handpiece, there was no device to prevent back suction. When the high speed handpiece stopped running, negative pressure was generated. The high speed handpiece mainly caused pollution through the following two ways:
(1) Through the exhaust pipe circuit: When the air supply is stopped, the inertial rotation of the bur produces a pressure difference, causing foreign matter in the oral cavity to invade the interior of the exhaust pipe through the machine head. Form a source of cross-infection.
(2) Foreign bodies (blood, saliva, debris, dirt, etc.) through the water supply pipe circuit: When the spraying is stopped, in order to prevent dripping, the general dental unit is equipped with a suction water supply device when it is stopped. At this time, the foreign matter in the oral cavity is sucked back into the water supply pipe of the high speed handpiece and invades the 10cm~20cm part of the handpiece tubing connecting the handpiece to the dental unit, forming a source of cross-infection.
After blood, saliva and debris enter the interior with air and water, they are distributed to the balls in the bearing, etc., becoming an important medium for cross-infection. Therefore, for the use of dental handpieces, it must be "one person (patient) one handpiece", that is, after each patient uses it, it must be sent for cleaning and disinfection, and it can be used again after packaging.
At present, the use of "hygienic handpieces" with anti-suckback devices is advocated. which have a check valve inside. It is a valve that controls water flow in one direction. It is built into the interface, which can prevent the dirt sucked back from the water supply pipe of the handpiece from entering the wire, prevent foreign matter from entering the mechanical seal structure, and discharge foreign matter from the gap in the machine head to the outside, preventing patients, Cross-infection among surgeons and staff. (Recommond SENDA SD-401 M4 "hygienic handpieces" with zero-suckback devices)
9. The perfection of high speed handpiece operation
Nowadays, the functions of dental handpiece are becoming more and more diverse. Some high speed handpiece are equipped with optical fiber lighting, and the lights are directly irradiated to the operating area when in use, which brings great convenience to doctors. The perfect optical fiber brightness of a high speed handpiece should be as close to natural light as possible. For convenience, it is best to choose a quick-connect type and push button type high speed handpiece. It is very fast to disassemble and install the bur, and it can also reduce pollution. (Recommond SENDA SD-701 fiber optic handpiece)
10. Reasonable price
The price of dental handpieces in the dental market varies greatly. You must take into account your own situation and fully consider important factors such as the service life of different handpieces, the investment in replacing bearings, the service life after replacing bearings, and the impact on doctors’ work efficiency. Instead of blindly pursuing the purchase of low-priced dental handpiece.
