In the dental field, the turbine is a key instrument for many clinical procedures. For this reason it is necessary to carefully consider which instrument to choose. Let's get to know this instrument better: how it is made and how it works.
As the name of the instrument suggests, the turbine works thanks to compressed air that reaches the handpiece through the tubes inside the unit and hits the blades making the rotor spin. The compressed air supply comes from the compressor which compresses the air up to a pressure of 8 bar inside its tank. As the air in the tank is used up by the dental turbine or syringe, the pressure drops to about 5 bar, on reaching this level the compressor is restarted to increase the pressure again.
Each dental unit incorporates a reducer whose purpose is to control the pressure of the compressor and keep it at a constant level. A proportional valve is provided to regulate the pressure delivered to the instrument. This valve regulates the flow of air according to the progressive actuation of the foot control. In the case of the dental turbine, the measured operating pressure will be 2 to 3 bar.
Inside the turbine there are components such as a rotor, consisting of a spindle, wheel, bearings, seals, etc. The turbine is connected to the compressed air tubes of the unit via quick couplings. This facilitates their replacement for cleaning and maintenance.
Thanks to compressed air, the turbine can reach high speeds up to 400,000 rpm. These speed values make it an ideal tool for removing enamel and hardened materials such as the materials used for prostheses. However, speed coupled with friction generates extreme heat levels. This requires the integration in the turbine of a cooling system through simultaneous irrigation with air and water.
When choosing a dental turbine, there are many possible alternatives, but the overall quality of the product has an influence on the effectiveness and durability of this handpiece. Let's review some aspects that must be evaluated to avoid choosing the wrong instrument.
The material from which the turbine is made
What matters is for the dentist to have a handpiece that is durable and capable of withstanding all the dynamic stress that it undergoes during surgery. This makes steel and aluminium alloys always a good solution.
The shape, surface and head of the turbine
There are three aspects to be considered for different reasons.
Different shapes are acceptable as the feel is subjective. The instrument must feel good in the dentist's hand. This instrument will be used very often during any work day, so it must have a comfortable grip.
The handpiece must have a handle that allows for an easy grip and, in terms of hygiene requirements, it must be perfectly smooth to facilitate cleaning and disinfection.
Finally, the dental turbine head. The smaller the head, the better its fit in the patient's mouth - resulting in better visibility for the dentist.
Power and low-noise operation
These are key values: a rotor capable of high power and cutting capacity is the heart of the turbine, as it is suitable for overcoming the strong resistance opposed by the material to be cut or removed.
Vibrations and noise level
The discomfort generated by a poorly built turbine is twofold: on the one hand, the dentist will be affected in the long run by vibration through their hand and wrist, on the other hand the patient will experience discomfort caused by the turbine noise which increases as vibrations increase.
Consider that a busy street or a hair dryer one metre from the listener's ear produces 70 dbA, while a vacuum cleaner 10 metres away produces 55 dbA. The noise produced by a turbine is usually between these two thresholds: the more we manage to reduce it, the less unpleasant it will be for the patient.
We can achieve this goal thanks to the construction quality of our turbine which minimizes vibrations and reduces sound pressure. In addition to the mechanical precision achieved by the instrument manufacturer, ceramic bearings, with their high mechanical resistance and low friction, are necessary to limit vibrations and noise.
LED lighting
Without adequate lighting, delivering dental care may prove harder. For this reason, today an LED light is used which, through optical fibres, can reach the turbine head directly. The life span of the diode is far superior to that of halogen light and emits white light, which does not alter the colour of the teeth and tissues.
Air and water coolant circuit
Considering the amount of heat produced, constant irrigation of the operating area is necessary in order not to damage the tooth pulp. Irrigation cools down the operating area and the body of the handpiece at the same time. In any case, multiple irrigation is needed to cool down effectively and clear the field of debris from the material removed by the turbine.
Three or four irrigation points are needed, arranged radially with respect to the bur. This allows a stable spray mist to be obtained, which ensures the best cooling and maximum visibility of the operating area in all working conditions.
Like all rotary instruments, and any other instrument, regular maintenance is needed to ensure longer life and consistent performance. In the case of turbines, efficient and frequent lubrication is essential. A combination of proper lubrication and ceramic bearings is certainly your best option. In any case, it is advisable to follow the indications of the turbine manufacturer.
Above all, the importance of choosing a quality turbine should be pointed out - avoiding cheap models that are not good value at all if they need to be replaced frequently. This is a common situation when poor construction quality or cheap materials are used, damaging internal components.
For turbine cleaning and sterilization tips, check the manufacturer's recommendations: the protocol provides for cleaning, disinfection, drying, lubrication, wrapping and sterilization in an autoclave.
There are devices available on the market that carry out simple lubrication and purging cycles of the dental turbine and other rotating instruments. This procedure can be carried out fully automatically with devices such as Thalya. With Thalya Plus it is possible to integrate cleaning, disinfection and drying into this process, before wrapping and sterilizing the instrument.
In the wide Anthos range, Silent Power Evo turbines stand out for their greater power, low-noise operation and longest life span. All this thanks to precision mechanics and top quality materials, geometries, set-up and lubrication.